Genome-wide association study identifies candidate genes for male fertility traits in humans.

Science.gov (United States)

Kosova, Gülüm; Scott, Nicole M; Niederberger, Craig; Prins, Gail S; Ober, Carole

2012-06-08

Despite the fact that hundreds of genes are known to affect fertility in animal models, relatively little is known about genes that influence natural fertility in humans. To broadly survey genes contributing to variation in male fertility, we conducted a genome-wide association study (GWAS) of two fertility traits (family size and birth rate) in 269 married men who are members of a founder population of European descent that proscribes contraception and has large family sizes. Associations between ∼250,000 autosomal SNPs and the fertility traits were examined. A total of 41 SNPs with p ≤ 1 × 10(-4) for either trait were taken forward to a validation study of 123 ethnically diverse men from Chicago who had previously undergone semen analyses. Nine (22%) of the SNPs associated with reduced fertility in the GWAS were also associated with one or more of the ten measures of reduced sperm quantity and/or function, yielding 27 associations with p values LRRC32, which encodes a latent transforming growth factor β (TGF-β) receptor on regulatory T cells. We suggest that mutations in these genes that are more severe may account for some of the unexplained infertility (or subfertility) in the general population. Copyright © 2012 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

[Is an act of human love the in vitro fertilization? A proposal ethical analysis].

Science.gov (United States)

García Sánchez, Emilio

2014-01-01

Since 1978, when the first test tube baby, Louis Brown, was born, thousands of children have been born every year through in vitro fertilization. Many families keep attending fertility clinics in order to receive some treatment for their infertility problems and have a child. Children born in this way are worthy human beings. Their parents love them and devote themselves to their children admirably, showing real parental love. However, does this loving kindness justify, from an ethical point of view, any way of desiring and having a son or daughter? Is it really an act of human love to long for a child and satisfy this desire using artificial methods? Is it equally human and worthy to wish them choosing in vitro fertilization than to wish them through an intimate and loving relationship, in which the child emerges as a result of interpersonal donation? I answer these questions by analyzing the ethics proposal formulated by Rhonheimer and Carrasco de Paula. In short, only the intimate and loving sexual union between a man and a woman -as long as it is unconditional love- may be the dignity cause of the existence of a human being. And such union and unconditional requirement are absent in vitro fertilization.

Detecting the Evolution of Deliberate Fertility Control before the Demographic Transition in Germany

Directory of Open Access Journals (Sweden)

Aliaksandr Amialchuk

2012-10-01

Full Text Available BACKGROUND Pervious literature has established the existence of deliberate non-parity-specific fertility control in pre-transitional populations. However, less focus has been given to the timing of its onset. In addition, previous studies focused on the changes in fertility in response to the local prices of grains, which may be endogenous. OBJECTIVE This paper studies the emergence and evolution of deliberate fertility control by investigating the link between child mortality and economic stress on the one hand and non-parity-specific birth control on the other, in historic German villages between 1700 and 1900. METHODS Birth histories from fourteen German villages (1700-1900 and rye price series are used in a micro-level event history analysis. The fertility response of second and higher-order births to the mortality of children over age two and exogenous fluctuations in rye price are used as measures of the extent of deliberate non-parity-specific birth control. RESULTS Over the course of the demographic transition, the effect of the death of children generally increases after controlling for the effect of the death of children less than two years old. The negative fertility response to high rye prices before and in the year immediately following the price change occurred only after 1800. CONCLUSIONS The replacement and insurance effects associated with child mortality generally increased before the demographic transition. The emergence of the negative effect of high rye prices on fertility after 1800 further supports the presence and evolution of deliberate non-parity-specific fertility control before the demographic transition.

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).

Using polymer-coated controlled-release fertilizers in the nursery and after outplanting

Science.gov (United States)

Thomas D. Landis; R. Kasten Dumroese

2009-01-01

Controlled-release fertilizers (CRF) are the newest and most technically advanced way of supplying mineral nutrients to nursery crops. Compared to conventional fertilizers, their gradual pattern of nutrient release better meets plant needs, minimizes leaching, and therefore improves fertilizer use efficiency. In our review of the literature, we found many terms used...

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

Reducing Runoff Loss of Applied Nutrients in Oil Palm Cultivation Using Controlled-Release Fertilizers

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A. Bah

2014-01-01

Full Text Available Controlled-release fertilizers are expected to minimize nutrient loss from crop fields due to their potential to supply plant-available nutrients in synchrony with crop requirements. The evaluation of the efficiency of these fertilizers in tropical oil palm agroecological conditions is not yet fully explored. In this study, a one-year field trial was conducted to determine the impact of fertilization with water soluble conventional mixture and controlled-release fertilizers on runoff loss of nutrients from an immature oil palm field. Soil and nutrient loss were monitored for one year in 2012/2013 under erosion plots of 16 m2 on 10% slope gradient. Mean sediments concentration in runoff amounted to about 6.41 t ha−1. Conventional mixture fertilizer posed the greatest risk of nutrient loss in runoff following fertilization due to elevated nitrogen (6.97%, potassium (13.37%, and magnesium (14.76% as percentage of applied nutrients. In contrast, this risk decreased with the application of controlled-release fertilizers, representing 0.75–2.44% N, 3.55–5.09% K, and 4.35–5.43% Mg loss. Meanwhile, nutrient loss via eroded sediments was minimal compared with loss through runoff. This research demonstrates that the addition of controlled-release fertilizers reduced the runoff risks of nutrient loss possibly due to their slow-release properties.

Issues of biomedically assisted fertilization before the European Court of Human Rights

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Bordaš Bernadet

2011-01-01

Full Text Available The development of biomedicine has led to the birth of the first test-tube baby in 1978, and that event gave enormous impetus for further development of biomedically assisted fertilization, but also for the development of supporting legislation. Biomedically assisted fertilization and its application raises sensitive social and moral issues, so states retain their sovereign rights in this area and enact rules and regulations that reflect their national legislative policy. Comparative studies across Europe show that national legal acts are in force in many countries, but differences exist and states persist on them. Legal regulation of biomedically assisted fertilization provides legal security for individuals who are subjected to it, making easier the legal protection in cases where individual rights are violated. This paper presents two recent judgments of the European Court of Human Rights, the subject matter of which are issues of biomedically assisted fertilization, where legal remedy is sought under Article 8 of the European Convention for the Protection of Human Rights and Fundamental Freedoms. Both judgments are in favor of the states against which complaints are filed by individuals: the Court ruled that national regulations have not violated the right to respect for the individual's private life.

Applying clinically proven human techniques for contraception and fertility to endangered species and zoo animals: a review.

Science.gov (United States)

Silber, Sherman J; Barbey, Natalie; Lenahan, Kathy; Silber, David Z

2013-12-01

Reversible contraception that does not alter natural behavior is a critical need for managing zoo populations. In addition to reversible contraception, other fertility techniques perfected in humans may be useful, such as in vitro fertilization (IVF) or oocyte and embryo banking for endangered species like amphibians and Mexican wolves (Canis lupus baileyi). Furthermore, the genetics of human fertility can give a better understanding of fertility in more exotic species. Collaborations were established to apply human fertility techniques to the captive population. Reversible vasectomy might be one solution for reversible contraception that does not alter behavior. Reversible approaches to vasectomy, avoiding secondary epididymal disruption, were attempted in South American bush dogs (Speothos venaticus), chimpanzees (Pan troglodytes), gorillas (Gorilla gorilla), Przewalski's horse (Equus przewalski poliakov), and Sika deer (Cervus nippon) in a variety of zoos around the world. These techniques were first perfected in > 4,000 humans before attempting them in zoo animals. In vitro fertilization with gestational surrogacy was used to attempt to break the vicious cycle of hand rearing of purebred orangutans, and egg and ovary vitrification in humans have led to successful gamete banking for Mexican wolves and disappearing amphibians. The study of the human Y chromosome has even explained a mechanism of extinction related to global climate change. The best results with vasectomy reversal (normal sperm counts, pregnancy, and live offspring) were obtained when the original vasectomy was performed "open-ended," so as to avoid pressure-induced epididymal disruption. The attempt at gestational surrogacy for orangutans failed because of severe male infertility and the lack of success with human ovarian hyperstimulation protocols. Vitrification of oocytes is already being employed for the Amphibian Ark Project and for Mexican wolves. Vasectomy can be a reversible contraception

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

Human fertility, molecular genetics, and natural selection in modern societies.

Directory of Open Access Journals (Sweden)

Felix C Tropf

Full Text Available Research on genetic influences on human fertility outcomes such as number of children ever born (NEB or the age at first childbirth (AFB has been solely based on twin and family-designs that suffer from problematic assumptions and practical limitations. The current study exploits recent advances in the field of molecular genetics by applying the genomic-relationship-matrix based restricted maximum likelihood (GREML methods to quantify for the first time the extent to which common genetic variants influence the NEB and the AFB of women. Using data from the UK and the Netherlands (N = 6,758, results show significant additive genetic effects on both traits explaining 10% (SE = 5 of the variance in the NEB and 15% (SE = 4 in the AFB. We further find a significant negative genetic correlation between AFB and NEB in the pooled sample of -0.62 (SE = 0.27, p-value = 0.02. This finding implies that individuals with genetic predispositions for an earlier AFB had a reproductive advantage and that natural selection operated not only in historical, but also in contemporary populations. The observed postponement in the AFB across the past century in Europe contrasts with these findings, suggesting an evolutionary override by environmental effects and underscoring that evolutionary predictions in modern human societies are not straight forward. It emphasizes the necessity for an integrative research design from the fields of genetics and social sciences in order to understand and predict fertility outcomes. Finally, our results suggest that we may be able to find genetic variants associated with human fertility when conducting GWAS-meta analyses with sufficient sample size.

Impact of DNA mismatch repair system alterations on human fertility and related treatments.

Science.gov (United States)

Hu, Min-hao; Liu, Shu-yuan; Wang, Ning; Wu, Yan; Jin, Fan

2016-01-01

DNA mismatch repair (MMR) is one of the biological pathways, which plays a critical role in DNA homeostasis, primarily by repairing base-pair mismatches and insertion/deletion loops that occur during DNA replication. MMR also takes part in other metabolic pathways and regulates cell cycle arrest. Defects in MMR are associated with genomic instability, predisposition to certain types of cancers and resistance to certain therapeutic drugs. Moreover, genetic and epigenetic alterations in the MMR system demonstrate a significant relationship with human fertility and related treatments, which helps us to understand the etiology and susceptibility of human infertility. Alterations in the MMR system may also influence the health of offspring conceived by assisted reproductive technology in humans. However, further studies are needed to explore the specific mechanisms by which the MMR system may affect human infertility. This review addresses the physiological mechanisms of the MMR system and associations between alterations of the MMR system and human fertility and related treatments, and potential effects on the next generation.

Silicone Doped Chitosan-Acrylamide Coencapsulated Urea Fertilizer: An Approach to Controlled Release Fertilizers

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Sempeho Ibahati Siafu

2017-01-01

Full Text Available In the absence of special management practices, urea is known to undergo chemical transformations resulting in severe losses (≈60–70% of total fertilizer applied. In an attempt to design urea controlled release fertilizers in order to counterbalance the 60–70% loss, urea was cross-linked with chitosan and acrylamide under refluxed in situ copolymerization technique; the procedures were repeated with silicone doping prior cross-linking with MBA. The particles were characterized with FTIR/ATR, EDX, XRD, and SEM. The IR bands observed within 3426–409 cm−1 revealed the formation of new bands after coencapsulation for the νγN-H, νβN-H, νOH, νsNH2, νCH2, νC=O, δ′NH2, νC=C, δNH2, νC-N, βCH3, $C-N, γNH2, νC=O, and $CH2. Crystallinity indices for urea with and without silicone doping were found to be 50.9% and 72.1%, respectively, with a distinctive split peak at (d 12.30°. The formation of Microdunes and Microballs 3D network sized 0.64 μm was noted. Release profiles demonstrated that 80% N was released in a period of 30 days at RT and pH 7. The release patterns exhibited linear and deformed sigmoid release models. Empirically, the findings demonstrated that it is possible to design urea controlled release fertilizers with varying particle sizes and morphologies by using chitosan-acrylamide coencapsulation.

Behavior genetic modeling of human fertility

DEFF Research Database (Denmark)

Rodgers, J L; Kohler, H P; Kyvik, K O

2001-01-01

Behavior genetic designs and analysis can be used to address issues of central importance to demography. We use this methodology to document genetic influence on human fertility. Our data come from Danish twin pairs born from 1953 to 1959, measured on age at first attempt to get pregnant (First......Try) and number of children (NumCh). Behavior genetic models were fitted using structural equation modeling and DF analysis. A consistent medium-level additive genetic influence was found for NumCh, equal across genders; a stronger genetic influence was identified for FirstTry, greater for females than for males....... A bivariate analysis indicated significant shared genetic variance between NumCh and FirstTry....

A review of mathematical modeling and simulation of controlled-release fertilizers.

Science.gov (United States)

Irfan, Sayed Ameenuddin; Razali, Radzuan; KuShaari, KuZilati; Mansor, Nurlidia; Azeem, Babar; Ford Versypt, Ashlee N

2018-02-10

Nutrients released into soils from uncoated fertilizer granules are lost continuously due to volatilization, leaching, denitrification, and surface run-off. These issues have caused economic loss due to low nutrient absorption efficiency and environmental pollution due to hazardous emissions and water eutrophication. Controlled-release fertilizers (CRFs) can change the release kinetics of the fertilizer nutrients through an abatement strategy to offset these issues by providing the fertilizer content in synchrony with the metabolic needs of the plants. Parametric analysis of release characteristics of CRFs is of paramount importance for the design and development of new CRFs. However, the experimental approaches are not only time consuming, but they are also cumbersome and expensive. Scientists have introduced mathematical modeling techniques to predict the release of nutrients from the CRFs to elucidate fundamental understanding of the dynamics of the release processes and to design new CRFs in a shorter time and with relatively lower cost. This paper reviews and critically analyzes the latest developments in the mathematical modeling and simulation techniques that have been reported for the characteristics and mechanisms of nutrient release from CRFs. The scope of this review includes the modeling and simulations techniques used for coated, controlled-release fertilizers. Copyright © 2017 Elsevier B.V. All rights reserved.

Methods of fertility control in cats: Owner, breeder and veterinarian behavior and attitudes.

Science.gov (United States)

Murray, Jane K; Mosteller, Jill R; Loberg, Jenny M; Andersson, Maria; Benka, Valerie A W

2015-09-01

Fertility control is important for population management of owned and unowned cats, provides health benefits at the individual level and can reduce unwanted sexually dimorphic behaviors such as roaming, aggression, spraying and calling. This article reviews the available evidence regarding European and American veterinarian, owner and pedigree cat breeder attitudes toward both surgical sterilization and non-surgical fertility control. It additionally presents new data on veterinarians' and pedigree cat breeders' use of, and attitudes toward, alternative modalities of fertility control. Within the United States and Europe, the proportion of cats reported to be sterilized varies widely. Published estimates range from 27-93% for owned cats and 2-5% for cats trapped as part of a trap-neuter-return (TNR) program. In some regions and populations of cats, non-surgical fertility control is also used. Social context, cultural norms, individual preferences, economic considerations, legislation and professional organizations may all influence fertility control decisions for cats. Particularly in Europe, a limited number of non-surgical temporary contraceptives are available for cats; these include products with regulatory approval for cats as well as some used 'off label'. Non-surgical methods remove the risk of complications related to surgery and offer potential to treat more animals in less time and at lower cost; they may also appeal to pedigree cat breeders seeking temporary contraception. However, concerns over efficacy, delivery methods, target species safety, duration and side effects exist with current non-surgical options. Research is under way to develop new methods to control fertility in cats without surgery. US and European veterinarians place high value on three perceived benefits of surgical sterilization: permanence, behavioral benefits and health benefits. Non-surgical options will likely need to share these benefits to be widely accepted by the veterinary

Doses of controlled-release fertilizer for production of rubber tree rootstocks

Directory of Open Access Journals (Sweden)

Renato Luis Grisi Macedo

2012-06-01

Full Text Available This experimental study aimed to evaluate the effects of doses of controlled-release fertilizer (ALL on the development of rubber tree rootstocks. The fertilizer used was Osmocote®, scheduled to be released for 8-9 months and with the following composition: N (15%, P2O5 (9%, K2O (12%, Mg (1%, S (2.3%, B (0.02%, Cu (0.05%, Fe (1%, Mn (0.06%, Mo (0.02% and Zn (0.05%. A randomized block design was used, with four treatments and eight replicates of 20 plants per plot. The controlled-release fertilizer was added to Rendimax Floreira® substrate at doses of 0, 3, 6 and 9 g per liter, and rootstocks were produced in plastic containers with a capacity of two liters of substrate. Three seeds of clone GT 1 were scattered in each container and thinning was performed on day 60, leaving the most vigorous plant only. After the fourth leaf shot from each rootstock, the containers of each treatment were topped, due to compaction, with 300 mL of the relevant fertilizer and substrate mixture. The rootstocks were evaluated at eight months of age as to height, stem diameter (DC 5 cm above root collar, total dry matter, shoot and root dry matter, leaf nutrient levels and percentage of plants suitable for grafting (DC≥1.0 cm. Results revealed that adequate development and nutrition of rootstocks was achieved by using 6 g of controlled-release fertilizer per liter of substrate.

Adolescent leadership and adulthood fertility: revisiting the "central theoretical problem of human sociobiology".

Science.gov (United States)

Jokela, Markus; Keltikangas-Järvinen, Liisa

2009-02-01

Human motivation for social status may reflect an evolved psychological adaptation that increased individual reproductive success in the evolutionary past. However, the association between status striving and reproduction in contemporary humans is unclear. It may be hypothesized that personality traits related to status achievement increase fertility even if modern indicators of socioeconomic status do not. We examined whether four subcomponents of type-A personality--leadership, hard-driving, eagerness, and aggressiveness--assessed at the age of 12 to 21 years predicted the likelihood of having children by the age of 39 in a population-based sample of Finnish women and men (N=1,313). Survival analyses indicated that high adolescent leadership increased adulthood fertility in men and women, independently of education level and urbanicity of residence. The findings suggest that personality determinants of status achievement may predict increased reproductive success in contemporary humans.

Feasibility of surveillance of changes in human fertility and semen quality.

Science.gov (United States)

Stewart, T M; Brown, E H; Venn, A; Mbizvo, M T; Farley, T M; Garrett, C; Baker, H W

2001-01-01

There is concern that male fertility is declining, but this is difficult to study because few men volunteer for studies of semen quality, and recruitment bias may over-represent the subfertile. The Human Reproduction Programme of the World Health Organization developed a protocol for multicentre studies of fertility involving a questionnaire for pregnant women to obtain time to pregnancy (TTP): the number of menstrual cycles taken to conceive. Male characteristics and semen quality will be determined in a subset of the partners. Our aim was to validate the TTP questionnaire, and to examine potential recruitment bias and feasibility of conducting large-scale surveillance of fertility. The questionnaire was administered to 120 pregnant women (16-32 weeks). Validation included internal reliability by consistency of responses, test-re-test reliability by repeat administration (20 women) and accuracy by comparison of gestational age from first antenatal ultrasound and menstrual dates. Internal reliability was high. Agreement between categorical responses on re-testing was very good (k > 0.8). In both the re-test and gestational age analysis, differences in TTP of 1 cycle were found (standard deviation recruitment bias. Response rates indicate the feasibility of surveillance of fertility in large maternity centres.

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

Science.gov (United States)

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

2009-05-30

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

Influence of Human Chorionic Gonadotropin on the Fertility Rate in ...

African Journals Online (AJOL)

An experiment was carried out on the influence of human chorionic gonadotropin hormone (hCG) on the fertility rate of rabbit does under artificial insemination. The rabbit does (7-8 months old) were used for the trial. The hCG was administered to the rabbit does at varying doses: 0, 50, 100 and 150 I.U representing ...

[Controlling effect of antagonist bioorganic fertilizer on tomato root-knot nematode].

Science.gov (United States)

Zhu, Zhen; Chen, Fang; Xiao, Tong-jian; Wang, Xiao-hui; Ran, Wei; Yang, Xing-ming; Shen, Qi-rong

2011-04-01

Indoor in vitro culture experiment and greenhouse pot experiment were conducted to evaluate the capabilities of three bacterial strains XZ-173 (Bacillus amyloliquefaciens), SL-25 (B. gibsonii), and KS-62 (Paenibacillus polymyxa) that can hydrolyze collagen protein in controlling tomato root-knot nematode. In the in vitro culture experiment, suspensions of XZ-173, SL-25, and KS-62 induced a mortality rate of 75.9%, 66.7%, and 50.0% to the second-stage junior nematode within 24 h, and decreased the egg hatching rate to 17.8%, 28.9% and 37.6% after 7-day incubation, respectively, in contrast to the 17.4% mortality rate and 53.6% egg hatching rate in the control (sterilized water). In the greenhouse pot experiment, the bioorganic fertilizer mixed with equal parts of fermented XZ-173, SL-25, and KS-62 gained the best result, with the root-knot nematode population in rhizosphere soil decreased by 84.0% as compared with the control. The bioorganic fertilizer also decreased the numbers of galls and eggs on tomato roots significantly, and increased the underground and aboveground biomass of tomato. Therefore, antagonist bioorganic fertilizer has promising potential in controlling root-knot nematode.

Non-Monotonicity of Fertility in Human Capital Accumulation and Economic Growth

OpenAIRE

Spyridon Boikos; Alberto Bucci; Thanasis Stengos

2012-01-01

This paper investigates the relationship between per-capita human capital investment and the birth rate. Since the consequences of higher fertility (birth rate) on per-capita human capital accumulation (the so-called dilution effect) are not the same (in sign and magnitude) across different groups of countries with different birth rates, we analyze the growth impact of a non-linear dilution-effect. The main predictions of the model (concerning the relationship between population and economic ...

Status of fertility control in Egypt.

Science.gov (United States)

Hefnawi, F I

1982-01-01

The concern for fertility control is not alien to the cultural and religious heritage of Egypt. Historically, Egyptian interest in fertility dates to the Pharoahs. Contraceptive recipes written at least 15-18 centuries B.C. have been found. Romans may have borrowed some of the more effective methods from Egypt when it became part of the Roman Empire as evidenced by the decline in size of aristocratic Roman families at the beginning of the Christian era. Muslim conquerors of Egypt encouraged fertility control. In the 9th century differences of opinion about the legality of contraception appeared among the interpreters of Islamic law. Some methods found in the writings of Muslim doctors as al-Razi and Avicenna still survive in the folk medicine of Egypt. In modern times use of barrier methods of contraception were encouraged by family planning organizations in Egypt. The medical profession was not deeply involved since these methods did not require much medical assistance. In 1936 a religiouss verdict declared contraception to be a lawful act of Islam. National programs in family planning in the 1960's encouraged the use of the Lippes Loop IUD. The medical problem of blood loss associated with the IUD caused anxiety because of the high incidence of anemia in the female Egyptian population. There was also a cultural limitation on the wide use of the IUD. "Spotting" due to the IUD resulted in females being ritually unclean and therefore unfit to pray or observe the Islamic fast. The Pill, initially favored caused complications due to its effect on breast milk which is the universal source of nutrition for infants in Egypt. Replacement of the Pill by depo-provera injections during the post partum period of lactation is a practical solution. Permanent sterilization is limited to females and only performed when medically indicated. Abortion is illegal and permitted only as a therapeutic measure.

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)

Fertility drug use and the risk of ovarian tumors in infertile women: a case-control study.

Science.gov (United States)

Asante, Albert; Leonard, Phoebe H; Weaver, Amy L; Goode, Ellen L; Jensen, Jani R; Stewart, Elizabeth A; Coddington, Charles C

2013-06-01

To assess the influence of infertility and fertility drugs on risk of ovarian tumors. Case-control study (Mayo Clinic Ovarian Cancer Study). Ongoing academic study of ovarian cancer. A total of 1,900 women (1,028 with ovarian tumors and 872 controls, frequency matched on age and region of residence) who had provided complete information in a self-report questionnaire about history of infertility and fertility drug use. None. Effect of infertility history, use of fertility drugs and oral contraception, and gravidity on the risk of ovarian tumor development, after controlling for potential confounders. Among women who had a history of infertility, use of fertility drugs was reported by 44 (24%) of 182 controls and 38 (17%) of 226 cases. Infertile women who used fertility drugs were not at increased risk of developing ovarian tumors compared with infertile women who did not use fertility drugs; the adjusted odds ratio was 0.64 (95% CI, 0.37, 1.11). The findings were similar when stratified by gravidity and when analyzed separately for borderline versus invasive tumors. We found no statistically significant association between fertility drug use and risk of ovarian tumors. Further larger, prospective studies are needed to confirm this observation. Published by Elsevier Inc.

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

Science.gov (United States)

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

2016-09-01

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

Postmating sexual conflict and female control over fertilization during gamete interaction.

Science.gov (United States)

Firman, Renée C

2018-06-01

Males and females rarely have identical evolutionary interests over reproduction, and when the fitness of both sexes is dependent upon paternity outcomes, sexual conflict over fertilization is inevitable. In internal fertilizers, the female tract is a formidable selective force on the number and integrity of sperm that reach the egg. Selection on sperm quality is intensified when females mate multiply and rival males are forced to compete for fertilizations. While male adaptations to sperm competition have been well documented (e.g., increased sperm fertilizing capacity), much less attention has been given to the evolutionary consequences of postmating sexual conflict for egg form and function. Specifically, increased sperm competitiveness can be detrimental by giving rise to an elevation in reproductive failure resulting from polyspermy. Spanning literature on both internal and external fertilizers, in this review I discuss how females respond to sperm competition via fertilization barriers that mediate sperm entry. These findings, which align directly with sexual conflict theory, indicate that females have greater control over fertilization than has previously been appreciated. I then consider the implications of gametic sexual conflict in relation to the development of reproductive isolation and speculate on potential mechanisms accounting for "egg defensiveness." Finally, I discuss the functional significance of egg defensiveness for both the sexes, and sperm selection for females. © 2018 New York Academy of Sciences.

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

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)

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)

Human sperm degradation of zona pellucida proteins contributes to fertilization.

Science.gov (United States)

Saldívar-Hernández, Analilia; González-González, María E; Sánchez-Tusié, Ana; Maldonado-Rosas, Israel; López, Pablo; Treviño, Claudia L; Larrea, Fernando; Chirinos, Mayel

2015-09-02

The mammalian oocyte extracellular matrix known as the zona pellucida (ZP) acts as a barrier to accomplish sperm fusion with the female gamete. Although penetration of the ZP is a limiting event to achieve fertilization, this is one of the least comprehended stages of gamete interaction. Even though previous studies suggest that proteases of sperm origin contribute to facilitate the passage of sperm through the ZP, in human this process is not yet fully understood. The aim of this study was to determine the ability of human sperm to degrade recombinant human ZP (rhZPs) proteins and to characterize the proteases involved in this process. Purified rhZP2, rhZP3 and rhZP4 proteins were incubated with capacitated sperm and the proteolytic activity was determined by Western blot analysis. To further characterize the proteases involved, parallel incubations were performed in the presence of the protease inhibitors o-phenanthroline, benzamidine and MG-132 meant to block the activity of metalloproteases, serine proteases and the proteasome, respectively. Additionally, protease inhibitors effect on sperm-ZP binding was evaluated by hemizona assay. The results showed that rhZPs were hydrolyzed in the presence of capacitated sperm. O-phenanthroline inhibited the degradation of rhZP3, MG-132 inhibited the degradation of rhZP4 and benzamidine inhibited the degradation of the three proteins under investigation. Moreover, hemizona assays demonstrated that sperm proteasome inhibition impairs sperm interaction with human native ZP. This study suggests that sperm proteasomes could participate in the degradation of ZP, particularly of the ZP4 protein. Besides, metalloproteases may be involved in specific degradation of ZP3 while serine proteases may contribute to unspecific degradation of the ZP. These findings suggest that localized degradation of ZP proteins by sperm is probably involved in ZP penetration and may be of help in understanding the mechanisms of fertilization in humans.

Socio-economic differences in fertility control. Is there an early warning system at the village level?

Science.gov (United States)

Gutmann, M P; Watkins, S C

1990-05-01

"This article is about identifying the origins of fertility limitation in a way designed to overcome the constraints which require that fertility control be discovered only after it is undeniable. The analysis is based on data from the Belgian commune of La Hulpe, covering the period from 1846-1880. It shows (using hazard models) that the clearest signs of fertility control were visible among literate women and the bourgeoisie." (SUMMARY IN FRE) excerpt

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).

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.;

Effect of Soybean and Wheat as Cover Crops on Corn Yield and Weed Control using Different Fertilizer Sources

Directory of Open Access Journals (Sweden)

F. Dadashi

2016-02-01

Full Text Available Introduction: According to the importance of corn in supplying the human food directly and indirectly, it is one of the most important plants among crops. One of the major problems in corn production systems, is competition with weeds that reduce corn yield significantly. Weeds not only reduce crop yields but also decrease the commercial quality and the feeding palatability of main crops. They enhance the soil seed bank of weeds, which may cause continuous weed infestation of field crops as well. Herbicide application is a reliable and highly effective method for weed control. However, demand for safe food products that have been produced with a minimum application of chemical inputs is increasing. Therefore, farmers interested in weed management have to rely on other control approaches. An alternative weed control method is the use of cover crops, which can suppress the growth of weeds by preventing them from light and by producing allelopathic compounds. Cover crops successfully have been integrated into conservational agriculture systems in many areas of the world. Legumes are used as cover crop because of their rapid growth, in addition their potential to provide further nitrogen,along with high ability to compete with weeds. Materials and Methods: In order to study the effect of cover crops (soybean and wheat and different fertilizers sources on yield of corn and weed control, a filed experiment was conducted in randomized complete block design with three replications in 2012. Treatments included two cover crop (wheat and soybean and three fertilizer (no fertilizer, chemical fertilizer and compost..Fertilizer treatments was used according to soil analysis and requirement of corn (as a main plant. Weed-infestation and weed-free plots were used as controls. Study cultivars of corn, wheat and soybean were NS-640, Milan and Sari, respectively. Planting of corn was in June and cover crop was planted with corn simultaneously and between corn rows

Viable acrosome-intact human spermatozoa in the ejaculate as a marker of semen quality and fertility status

DEFF Research Database (Denmark)

Egeberg Palme, Dorte Louise; Rehfeld, Anders; Bang, Anne Kirstine

2018-01-01

STUDY QUESTION: Is it possible, in an unbiased and clinical relevant way, to determine the number of viable acrosome-intact human spermatozoa in ejaculates and to use this as a measure of fertility chances? SUMMARY ANSWER: Image cytometry enables easy and unbiased quantification of viable acrosome......-intact spermatozoa and it correlates with semen quality and fertility status. WHAT IS KNOWN ALREADY: The presence of the acrosome and its ability to respond to physiological inducers (e.g. progesterone) in the female reproductive tract at the appropriate time and place is required for fertilization. However......, the available assays are labor intensive and therefore not used clinically. STUDY DESIGN, SIZE, DURATION: Washed semen samples and capacitated swim-up fractions from volunteers were used to develop the assay. Subsequently washed ejaculates from patients in fertility treatment (n = 156), proven fertile men (n...

Pollution control -- Recovery of uranium from phosphatic fertilizer industry

International Nuclear Information System (INIS)

Trivedi, R.N.; Pachaiyappan, V.

1979-01-01

Various uranium recovery processes, viz. Brazilian process (HCL leaching), selective extraction of U, Japanese process, ORNL process and the Indian methods, recently developed, pertaining to the fertilizer industry are reviewed and their relative merits are discussed. Special attention has been paid to the recovery of uranium from the Indian and imported phosphatic rocks, showing the advantages, both from the pollution control and nuclear energy aspects. (K.B.)

Association between human leukocyte antigen-G genotype and success of in vitro fertilization and pregnancy outcome

DEFF Research Database (Denmark)

Hviid, T V F; Hylenius, S; Lindhard, A

2004-01-01

spontaneous abortions (RSA), 29 white women undergoing IVF treatments, 61 RSA women and 93 fertile controls were HLA-G genotype. The HLA-G genotype, homozygous for the presence of the 14 bp sequence in exon 8, was significantly associated with reduced fertility with respect to unsuccessful IVF treatments...

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.

Foliar Potassium Fertilizer Additives Affect Soybean Response and Weed Control with Glyphosate

Directory of Open Access Journals (Sweden)

Kelly A. Nelson

2012-01-01

Full Text Available Research in 2004 and 2005 determined the effects of foliar-applied K-fertilizer sources (0-0-62-0 (%N-%P2O5-%K2O-%S, 0-0-25-17, 3-18-18-0, and 5-0-20-13 and additive rates (2.2, 8.8, and 17.6 kg K ha−1 on glyphosate-resistant soybean response and weed control. Field experiments were conducted at Novelty and Portageville with high soil test K and weed populations and at Malden with low soil test K and weed populations. At Novelty, grain yield increased with fertilizer additives at 8.8 kg K ha−1 in a high-yield, weed-free environment in 2004, but fertilizer additives reduced yield up to 470 kg ha−1 in a low-yield year (2005 depending on the K source and rate. At Portageville, K-fertilizer additives increased grain yield from 700 to 1160 kg ha−1 compared to diammonium sulfate, depending on the K source and rate. At Malden, there was no yield response to K sources. Differences in leaf tissue K (P=0.03, S (P=0.03, B (P=0.0001, and Cu (P=0.008 concentrations among treatments were detected 14 d after treatment at Novelty and Malden. Tank mixtures of K-fertilizer additives with glyphosate may provide an option for foliar K applications.

The relationship of long term global temperature change and human fertility.

Science.gov (United States)

Fisch, Harry; Andrews, Howard F; Fisch, Karen S; Golden, Robert; Liberson, Gary; Olsson, Carl A

2003-07-01

According to the United Nations, global fertility has declined in the last century as reflected by a decline in birth rates. The earth's surface air temperature has increased considerably and is referred to as global warming. Since changes in temperature are well known to influence fertility we sought to determine if a statistical relationship exists between long-term changes in global air temperatures and birth rates. The most complete and reliable birth rate data in the 20th century was available in 19 industrialized countries. Using bivariate and multiple regression analysis, we compared yearly birth rates from these countries to global air temperatures from 1900 to 1994.A common pattern of change in birth rates was noted for the 19 industrialized countries studied. In general, birth rates declined markedly throughout the century except during the baby boom period of approximately 1940 to 1964. An inverse relationship was found between changes in global temperatures and birth rates in all 19 countries. Controlling for the linear yearly decline in birth rates over time, this relationship remained statistically significant for all the 19 countries in aggregate and in seven countries individually (phuman fertility may have been influenced by change in environmental temperatures.

Human fertility variation, size-related obstetrical performance and the evolution of sexual stature dimorphism

OpenAIRE

Guégan, Jean-François; Teriokhin, A.T.; Thomas, F.

2000-01-01

In several animal species, change in sexual size dimorphism is a correlated response to selection on fecundity. In humans, different hypotheses have been proposed to explain the variation of sexual dimorphism in stature, but no consensus has yet emerged. In this paper, we evaluate from a theoretical and an empirical point of view the hypothesis that the extent of sexual dimorphism in human populations results from the interaction between fertility and size-related obstetric complications. We ...

Phosphate fertilizer and weed control effects on growth and yield of ...

African Journals Online (AJOL)

Soil acidity and the associated low phosphorus availability and poor crop management practices are among the major factors constraining field pea productivity in the highlands of Ethiopia. The effect of phosphate fertilizer and weed control on yield and yield components of field pea (Pisum sativum L.) were studied on ...

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.

Kerala reaps low fertility dividends.

Science.gov (United States)

1992-01-01

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

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

Does fertility status influence impulsivity and risk taking in human females? Adaptive influences on intertemporal choice and risky decision making.

Science.gov (United States)

Kaighobadi, Farnaz; Stevens, Jeffrey R

2013-07-18

Informed by the research on adaptive decision making in other animal species, this study investigated human females' intertemporal and risky choices across the ovulatory cycle. We tested the hypothesis that at peak fertility, women who are exposed to environments that signal availability of higher quality mates (by viewing images of attractive males), become more impulsive and risk-seeking in economic decision tasks. To test this, we collected intertemporal and risky choice measures before and after exposure to images of either attractive males or neutral landscapes both at peak and low fertility conditions. The results showed an interaction between women's fertility status and image type, such that women at peak fertility viewing images of attractive men chose the smaller, sooner monetary reward option less than women at peak fertility viewing neutral images. Neither fertility status nor image type influenced risky choice. Thus, though exposure to images of men altered intertemporal choices at peak fertility, this occurred in the opposite direction than predicted--i.e., women at peak fertility became less impulsive. Nevertheless, the results of the current study provide evidence for shifts in preferences over the ovulatory cycle and opens future research on economic decision making.

Does Fertility Status Influence Impulsivity and Risk Taking in Human Females? Adaptive Influences on Intertemporal Choice and Risky Decision Making

Directory of Open Access Journals (Sweden)

Farnaz Kaighobadi

2013-07-01

Full Text Available Informed by the research on adaptive decision making in other animal species, this study investigated human females' intertemporal and risky choices across the ovulatory cycle. We tested the hypothesis that at peak fertility, women who are exposed to environments that signal availability of higher quality mates (by viewing images of attractive males, become more impulsive and risk-seeking in economic decision tasks. To test this, we collected intertemporal and risky choice measures before and after exposure to images of either attractive males or neutral landscapes both at peak and low fertility conditions. The results showed an interaction between women's fertility status and image type, such that women at peak fertility viewing images of attractive men chose the smaller, sooner monetary reward option less than women at peak fertility viewing neutral images. Neither fertility status nor image type influenced risky choice. Thus, though exposure to images of men altered intertemporal choices at peak fertility, this occurred in the opposite direction than predicted—i.e., women at peak fertility became less impulsive. Nevertheless, the results of the current study provide evidence for shifts in preferences over the ovulatory cycle and opens future research on economic decision making.

Ionizing radiation dose due to the use of agricultural fertilizers

International Nuclear Information System (INIS)

Umisedo, Nancy Kuniko

2007-01-01

Among several agents that exist in the environment which can expose to different risks and effects, there is the ionizing radiation whose knowledge of dose is of importance to the effective control and prevention of possible damages to human beings and to the environment. The transfer of radionuclides from fertilizers to/and soils to the foodstuffs can result as an increment in the internal dose when they are consumed by the human beings. This work evaluates the contribution of fertilizers to the ionizing radiation dose in the environment and in the human being. Samples of fertilizers, soils and vegetables produced in fertilized soils were analysed through gamma spectrometry with the use of a hyper pure germanium detector. Measurements of ambient dose with thermoluminescent dosimeters were also performed. In the fertilized soil samples values of specific activities from 36 to 342 Bq/kg for K-40, from 42 to 142 Bq/kg for U-238 and from 36 to 107 Bq/kg for Th-232 were obtained. In the vegetables the values varied from 21 to 118 Bq/kg for K-40 and for the elements of uranium and thorium series the values were less than 2 Bq/kg. In fertilizers the maximum value of 5800 Bq/kg was obtained for K-40, 430 Bq/kg for U-238 and 230 Bq/kg for Th-232. The average values of soil to plant transfer factor were not significantly different among the types of vegetables. The annual committed effective dose of 0.882 μSv due to the ingestion of K-40 from the analysed vegetables is very small if compared to the reference value of 170 μv given by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR, 2000). The thermoluminescent dosimetry provided the annual ambient dose equivalent from 1.5 to 1.8 mSv without differences between cultivated and non cultivated fields. Through the results obtained, it was not observed a significant transfer of radionuclides from fertilizers to soils and to foodstuffs in the conditions adopted in this work and consequently there

In vitro development of donated frozen-thawed human embryos in a prototype static microfluidic device: a randomized controlled trial

NARCIS (Netherlands)

Kieslinger, Dorit C.; Hao, Zhenxia; Vergouw, Carlijn G.; Kostelijk, Elisabeth H.; Lambalk, Cornelis B.; le Gac, Severine

Objective: To compare the development of human embryos in microfluidic devices with culture in standard microdrop dishes, both under static conditions. Design: Prospective randomized controlled trial. Setting: In vitro fertilization laboratory. Patient(s): One hundred eighteen donated frozen-thawed

Collaboration between industry and academia--prospects for male fertility control.

Science.gov (United States)

Stock, G; Habenicht, U F

1999-12-01

Drug development within the pharmaceutical industry is probably the field with the highest level of regulations. Due to the complexity of the different components of drug development and drug surveillance the need for a sophisticated organization and infrastructure is obvious. In addition, there is a necessity for sufficient resources and long-term commitment as well as logistic and long-term knowledge management. In order to secure high professional standards at all levels of this highly complex value creating chain, the number of cooperative arrangements in the pharmaceutical industry are increasing. The identification of new targets in the drug finding process calls in particular for outside partners. At the same time the preparedness of non-industrial researchers to cooperate with industry has also increased significantly. The area of fertility control, especially male fertility control, provides an excellent example for this kind of cooperation between industrial and non-industrial partners. Here a cooperative network is described which probably meets practically all relevant criteria for both the non-industrial but also the industrial partner. Some principles for the management of such a cooperative network are discussed. We believe that this kind of network can serve as a model for similar networks in other fields.

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.

Ammonia and carbon dioxide emissions by stabilized conventional nitrogen fertilizers and controlled release in corn crop

Directory of Open Access Journals (Sweden)

Taylor Lima de Souza

Full Text Available ABSTRACT The market of stabilized, slow and controlled release nitrogen (N fertilizers represents 1% of the world fertilizer consumption. On the other hand, the increase in availability, innovation and application of these technologies could lead to the improvement of N use efficiency in agroecossystems and to the reduction of environmental impacts. The objective of this study was to quantify agronomic efficiency relative index, ammonia volatilization, and CO2 emissions from conventional, stabilized and controlled release N fertilizers in corn summer crop. The experiment was carried out in a corn crop area located in Lavras, state of Minas Gerais, Brazil, without irrigation. All treatments were applied in topdressing at rate of 150 kg ha-1 N. N-NH3 losses from N fertilizers were: Granular urea (39% of the applied N = prilled urea (38% > urea coated with 16% S0 (32% = blend of urea + 7.9% S0 + polymers + conventional urea (32% > prilled urea incorporated at 0.02 m depth (24% > urea + 530 mg kg-1 of NBPT (8% = Hydrolyzed leather (9% > urea + thermoplastic resin (3% = ammonium sulfate (1% = ammonium nitrate (0.7%. Thermoplastic resin coated urea, ammonium nitrate and ammonium sulfate presented low values of cumulative CO2 emissions in corn crop. On the other hand, hydrolyzed leather promoted greater C-CO2 emission, when compared with other nitrogen fertilizers.

[Nutrient use efficiency and yield-increasing effect of single basal application of rice specific controlled release fertilizer].

Science.gov (United States)

Chen, Jiansheng; Xu, Peizhi; Tang, Shuanhu; Zhang, Fabao; Xie, Chunsheng

2005-10-01

A series of pot and field experiments and field demonstrations showed that in comparing with the commonly used specific-fertilizers containing same amounts of nutrients, single basal application of rice-specific controlled release fertilizer could increase the use efficiency of N and P by 12.2% - 22.7% and 7.0% - 35.0%, respectively in pot experiment, and the use efficiency of N by 17.1% in field experiment. In 167 field demonstrations successively conducted for 3 years in various rice production areas of Guangdong Province, single basal application of the fertilizer saved the application rate of N and P by 22.1% and 21.8%, respectively, and increased the yield by 8.2%, compared with normal split fertilization.

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

Science.gov (United States)

Ransom, J.I.

2012-01-01

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

Nitrogen mineralization and volatilization from controlled release urea fertilizers in selected malaysian soils

International Nuclear Information System (INIS)

Singh, K.J.K.A.; Yusop, M.K.; Oad, F.C.

2017-01-01

Controlled release urea fertilizers are usually used for extended duration in supplying nitrogen. The rate of urea hydrolysis could be efficiently minimized through these fertilizers. Various controlled released fertilizers i.e Uber-10 (30%N), Meister-20 (40%N), Meister-27 (40%N), Humate Coated Urea (45%N), Duration Polymer Coated Urea Type-V (43%N), Gold-N-Sulfur Coated Urea (41%N) and common urea (46%N) were applied to inland soil series of Malaysia. The soil series investigated were: Serdang (Typic Paleudult), Munchong (Typic Hapludox), Segamat (Typic Hapludox), Selangor (Typic Tropaquept), Rengam (Typic Kandiudult) and Holyrood (Typic Kandiudult). The maximum release of ammonium (NH/sub 4/-N) was noted in Gold-N-Sulfur Coated Urea, Humate Coated Urea and common Urea over 8 weeks of incubation. However, the release of NH4-N under the influence of Duration Type-V and Uber-10 took 2nd place. The Meister-20 and Meister-27 had minimum release of NH4-N. Munchong series was efficient in releasing higher NH4-N compared to rest of soils during 8th week of incubation due to higher soil total carbon, low /sub 4/-N and total nitrogen. Ammonia (NH/sub 3/-N) loss progressively increased with unit increase in incubation week and was higher during 6th week of fertilizer application. The higher loss of NH3-N was found in common Urea. However, Meister-20, Meister-27, Duration Polymer Coated Urea Type-V and Uber-10 had lower loss of NH/sub 3/-N due to slow release property and this character could be beneficial for supplying nutrients to next season crop. (author)

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

-based approaches have the benefit of being easily and conveniently accessed by individuals worldwide. However, the findings of the current study call into question the long-term efficacy of online fertility education, and suggest that variables such as gender and relevance need to be considered in assessing the efficacy of online fertility education strategies. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Expression of extracellular matrix metalloproteinase inducer (EMMPRIN) in the endometrium of patients with repeated implantation failure after in vitro fertilization.

Science.gov (United States)

Turgut, A; Goruk, N Y; Tunc, S Y; Agaçayak, E; Alabalik, U; Yalinkaya, A; Gül, T

2014-01-01

To compare the immunohistochemical expression of extracellular matrix metalloproteinase inducer (EMMPRIN) in repeated implantation failure (RIF) patients with normal fertile controls. The study group consisted of primary infertile patients with RIF and normal fertile controls between January 2011 and February 2013. Endometrial samples received at the luteal phase were exposed to immunohistochemical staining for EMMPRIN antibodies. EMMPRIN expression of endometrial glandular epithelial cells, stromal cells and vascular endothelial cells were evaluated. The main outcome measure was defined as immunohistochemical score with regard to the severity and extent of staining. The study group consisted of 26 primary infertile patients, whereas the control group consisted of 40 normal fertile controls. The fertile group was found to have stronger expression of EMMPRIN than the study group when endometrial glandular epithelial cells, stromal cells and vascular endothelial cells were evaluated with regards to the severity of staining (p EMMPRIN in the endometrial cells of the patients with RIF compared with fertile healthy controls. We suggest that reduced EMMPRIN expression in the human endometrium may lead to poor endometrial receptivity.

The Correlation of Human Development Index on Fertility and Mortality Rate: a Global Ecological Study

Directory of Open Access Journals (Sweden)

Amir Almasi-Hashiani

2016-12-01

Full Text Available BackgroundSeveral studies have examined the relationship between Human Development Index (HDI and various health outcomes. The aim of this study was to investigate the relationship between HDI, and infant mortality rate, mortality rate of children under one year and under 5 years, maternal mortality rate, and total fertility rate.Materials and MethodsIn this ecologic study, data on HDI, total fertility rate (TFR, maternal mortality rate (MMR, neonatal mortality rate (NMR, infant mortality rate (IMR and mortality rate in children under 5 years of age (< 5MR, were extracted from 188 countries in 2014 in the world. The data required in this study was obtained from the World Bank. Data analysis was performed using Pearson correlation in Stata version 12.0 software. ResultsIn this study, a negative significant correlation was observed between HDI and IMR (r = -0.878, P = 0.001, NMR (r = -0.870, 95% CI: -0.902, -0.828, P = 0.001, ConclusionIMR, children under one year old and under 5 years, and MMR mostly occur in developing countries. There was a correlation between HDI and its components, and the neonatal, infants, children under 5 years, maternal mortality rate and total fertility. The average annual percentage change of HDI also had a correlation with neonatal, infants, children under 5- year mortality rate, total fertility and maternal deaths.

Reduced rates of controlled-release fertilizer lower potential nitrogen leaching from a Wisconsin bare-root tree nursery

Science.gov (United States)

Ryosuke Fujinuma; Nick J. Balster; Hyung-Kyung. Lee

2011-01-01

Controlled-release fertilizer (CRF) typically increases nitrogen (N) fertilizer uptake and lowers N lost from the rooting zone via leaching. However, questions remain as to whether lower rates of CRF could further increase this efficiency, especially in sandy bare-root nurseries in Wisconsin. We hypothesized that: 1) a reduced CRF application at 60 percent of the...

Organic Biochar Based Fertilization

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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.

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, ...

[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

Some relations among cultural traditions, nuptiality and fertility.

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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

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 ...

Eleventh-year results of fertilization, herbaceous, and woody plant control in a loblolly pine plantation

Science.gov (United States)

James D. Haywood; Allan E. Tiarks

1990-01-01

Through 11 years, fertilization at planting significantly increased the stemwood volume (outside bark) per loblolly pine (Pinus taeda L.) on an intensively prepared moderately well-drained fine sandy loam site in northern Louisiana. Four years of herbaceous plant control significantly increased pine survival, and because herbaceous plant control...

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%.

Utilization of wheat straw for the preparation of coated controlled-release fertilizer with the function of water retention.

Science.gov (United States)

Xie, Lihua; Liu, Mingzhu; Ni, Boli; Wang, Yanfang

2012-07-18

With the aim of improving fertilizer use efficiency and minimizing the negative impact on the environment, a new coated controlled-release fertilizer with the function of water retention was prepared. A novel low water solubility macromolecular fertilizer, poly(dimethylourea phosphate) (PDUP), was "designed" and formulated from N,N'-dimethylolurea (DMU) and potassium dihydrogen phosphate. Simultaneously, an eco-friendly superabsorbent composite based on wheat straw (WS), acrylic acid (AA), 2-acryloylamino-2-methyl-1-propanesulfonic acid (AMPS), and N-hydroxymethyl acrylamide (NHMAAm) was synthesized and used as the coating to control the release of nutrient. The nitrogen release profile and water retention capacity of the product were also investigated. The degradation of the coating material in soil solution was studied. Meanwhile, the impact of the content of N-hydroxymethyl acrylamide on the degradation extent was examined. The experimental data showed that the product with good water retention and controlled-release capacities, being economical and eco-friendly, could be promising for applications in agriculture and horticulture.

Human Fertility Increases with the Marital-radius

DEFF Research Database (Denmark)

Labouriau, Rodrigo; Amorim, António

2008-01-01

We report a positive association between marital radius (distance between mates' birthplaces) and fertility detected in a large population. Spurious association due to socioeconomic factors is discarded by a conditional analysis involving income, education, and urbanicity. Strong evidence...

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

Controlled release fertilizers using superabsorbent hydrogel prepared by gamma radiation

International Nuclear Information System (INIS)

Elbarbary, Ahmed M.; Ghobashy, Mohamed Mohamady

2017-01-01

Superabsorbent hydrogels (PVP/CMC) based on polyvinylpyrrolidone (PVP)/carboxylmethyl cellulose (CMC) of different copolymer compositions were prepared by gamma radiation. Factors affecting the gel content (%) and the swelling ratio (g/g) of hydrogel such as irradiation dose as well as copolymer composition were investigated. With increasing the CMC content in PVP/CMC hydrogels, increases the swelling and improves the water retention capability. The high swelling ratio was observed at copolymer composition of PVP/CMC (60/40). Fast swelling of the hydrogels was obtained after 20 min. The effect of different fertilizers and buffers of different pH's on equilibrium swelling of hydrogels was investigated. Fertilizers such as urea, monopotassium-phosphate (MPK), and nitrogen-phosphate-potassium (NPK) were loaded onto the hydrogel to supply nitrogen, potassium and phosphorous nutrients. PVP/CMC hydrogels retained 28-36% after 72 h and slow retention was noticed up to 9 days. The swelling of hydrogel in fertilizer solutions is lower than that in water. The hydrogels showed adsorption desorption of fertilizers which governs by slow release property. The release rate of urea is much higher 10 times than that of phosphate. After 3 days, urea released 60%, while phosphate released 10-12%. The applicability of PVP/CMC hydrogels in the agricultural fields shows greater growth effect on zea maize plants. The growth of zea maize plant in soil mixed with PVP/CMC hydrogels loaded fertilizers is greater than untreated soil. The slow release fertilize, the high swelling and the slow water retention behaviors of PVP/CMC hydrogels encourage their use as safer release systems for fertilizers and as soil conditioner in agricultural applications.

Controlled release fertilizers using superabsorbent hydrogel prepared by gamma radiation

Energy Technology Data Exchange (ETDEWEB)

Elbarbary, Ahmed M.; Ghobashy, Mohamed Mohamady [Atomic Energy Authority, Nasr City (Egypt). National Center for Radiation Research and Technology (NCRTT)

2017-07-01

Superabsorbent hydrogels (PVP/CMC) based on polyvinylpyrrolidone (PVP)/carboxylmethyl cellulose (CMC) of different copolymer compositions were prepared by gamma radiation. Factors affecting the gel content (%) and the swelling ratio (g/g) of hydrogel such as irradiation dose as well as copolymer composition were investigated. With increasing the CMC content in PVP/CMC hydrogels, increases the swelling and improves the water retention capability. The high swelling ratio was observed at copolymer composition of PVP/CMC (60/40). Fast swelling of the hydrogels was obtained after 20 min. The effect of different fertilizers and buffers of different pH's on equilibrium swelling of hydrogels was investigated. Fertilizers such as urea, monopotassium-phosphate (MPK), and nitrogen-phosphate-potassium (NPK) were loaded onto the hydrogel to supply nitrogen, potassium and phosphorous nutrients. PVP/CMC hydrogels retained 28-36% after 72 h and slow retention was noticed up to 9 days. The swelling of hydrogel in fertilizer solutions is lower than that in water. The hydrogels showed adsorption desorption of fertilizers which governs by slow release property. The release rate of urea is much higher 10 times than that of phosphate. After 3 days, urea released 60%, while phosphate released 10-12%. The applicability of PVP/CMC hydrogels in the agricultural fields shows greater growth effect on zea maize plants. The growth of zea maize plant in soil mixed with PVP/CMC hydrogels loaded fertilizers is greater than untreated soil. The slow release fertilize, the high swelling and the slow water retention behaviors of PVP/CMC hydrogels encourage their use as safer release systems for fertilizers and as soil conditioner in agricultural applications.

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.

Organics and mineral fertilizers and biological control on the incidence of stalk rot and corn yield

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Elena Blume

2014-06-01

Full Text Available The expansion of area under maize (Zea mays L. and the use of no tillage have favored the incidence of stalk rot on this crop. The study aimed to evaluate the organic fertilizers and the treatment of corn seeds with Trichoderma spp. on the production of dry matter (DM of shoot, incidence of stalk rot and corn yield. The experiment consisted in a factorial with split-plot in strips, on the randomized block design with four replicates, and the fertilization treatments (pig slurry; swine deep bedding; cattle slurry; mineral fertilizer; control treatment were applied to the plots and the seeds treatment (with and without Trichoderma spp. in the subplots. At the flowering stage, three corn plants per subplot were collected for the assessment of DM production. At physiological maturity stage, the incidence of stalk rot was assessed, and the ears of corn harvested for productivity assessment. The organic and mineral fertilizers increased the production of DM and productivity of corn. Trichoderma spp. increased the production of DM of corn, but had no reflection on productivity. The incidence of stalk rot in corn was higher in treatments with organic and mineral fertilization. Organic fertilizers increase dry matter production of shoot and corn yield, and Trichoderma spp. provides an increase in dry matter production of shoot.

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

Science.gov (United States)

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

2015-01-01

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

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 ...

Effects of entomopathogenic fungus species, and impact of fertilizers, on biological control of pecan weevil (Coleoptera: Curculionidae).

Science.gov (United States)

Shapiro-Ilan, David I; Gardner, Wayne A; Wells, Lenny; Cottrell, Ted E; Behle, Robert W; Wood, Bruce W

2013-04-01

The pecan weevil, Curculio caryae (Horn), is a key pest of pecan, Carya illinoinensis (Wangenh.) K. Koch. Prior research indicated the potential for use of Hypocreales fungi to suppress C. caryae. We compared the efficacy of two fungal spp., Beauveria bassiana (GHA strain) and Metarhizium brunneum (F52), in their ability to cause C. caryae mortality. The fungus, B. bassiana, was applied to trunks of pecan trees (a method previously shown to be effective in C. caryae suppression) and efficacy was compared with M. brunneum applied to the ground or to the trunk with or without SoyScreen Oil as an ultraviolet protecting agent. Results indicated B. bassiana to be superior to M. brunneum regardless of application method; consequently, the potential for applying B. bassiana to control C. caryae was explored further. Specifically, the impact of different fertilizer regimes (as used by pecan growers) on the persistence of B. bassiana (GHA) in soil was determined. B. bassiana was applied to soil in a pecan orchard after one of several fertilizer treatments--i.e., ammonium nitrate, crimson clover, poultry litter, clover plus poultry litter, and a no-fertilizer control. B. bassiana persistence up to 49 d in 2009 and 2010 was assessed by plating soil onto selective media and determining the number of colony forming units, and by baiting soil with a susceptible host, Galleria mellonella (L.). Fertilizer treatments did not impact B. bassiana persistence. We conclude that standard fertilizers for nitrogen management, when applied according to recommended practices, are unlikely to negatively impact survival of B. bassiana in pecan orchards when the fungus is applied for C. caryae suppression during weevil emergence. Additional research on interactions between entomopathogenic fungi and fertilizer amendments (or other tree nutrition or soil management practices) is merited.

Integrated Public Education, Fertility and Human Capital

Science.gov (United States)

Azarnert, Leonid V.

2014-01-01

This paper analyzes the consequences of integration in public education. I show that the flight from the integrated multicultural public schools to private education increases private educational expenditures and, as a result, decreases fertility among more affluent parents whose children flee. In contrast, among less prosperous parents…

Phosphorus Characteristics with Controlled Nitrogen in Fertile Soils in Protected Vegetable Field

Directory of Open Access Journals (Sweden)

WANG Heng

2014-06-01

Full Text Available There is an unreasonable phenomenon of fertilization in vegetable facility cultivation, with the serious imbalance of soil nutrient. In purpose of understanding the absorption characteristics of phosphorus from nitrogen-rich soil, a long-term nitrogen-controlled experiment was carried from the year 2004 to 2007, and a split plot experiment of leaching was carried in winter-spring season of 2007. The results showed that the content of phosphorus varied with different nitrogen control. The TP was decreased with nitrogen supply of none(NN 、organic manure(MN 、organic manure and straw(MN+S, and the decreased range was NN>MN>MN+S, meanwhile the increase range of TP was traditional-nitrogen(CN >traditional-nitrogen+straw(CN+S >optimized-nitrogen+straw(SN+S >optimized-nitrogen(SN. The available P with CN and CN+S reached to 213.7 mg· kg -1 、225.4 mg·kg -1, which increased by 17.1 percent and 23.5 percent, which declared the phosphorus was accumulated; The available P with other nitrogen controlled decreased with the range of NN>MN>MN+S>SN+S>SN跃CN>CN+S, which showed that the supply reduction of nitrogen could slowdown the phosphorus accumulated and promote the utilization ratio of phosphorus. The organophosphorus was increased except NN, with obvious increase with CN、CN+S（308.4 mg·kg -1 、331.4 mg·kg -1 by 28.5 percent and 38.2 percent. The absorption coefficient of phosphorus with SN+S(P 2 O 5，mg· 100 g -1 reached to 1 571, increased by 143.6 percent; Otherwise the absorption coefficient of phosphorus with CN、CN+S showed negative growth, the CN dipped to 416（P 2 O 5，mg·100 g -1 by 35.5 percent. Adding wheat straw could greatly improved the capacity of absorption of phosphorus and slow down the accumulation of available phosphorus to some extent. The concentrations of total phosphorus in the filtrate with SN+S were less than SN, contrary to the concentration of organophosphorus, thus the straw returning had a certain effect on

A single nucleotide polymorphism within the novel sex-linked testis-specific retrotransposed PGAM4 gene influences human male fertility.

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Hidenobu Okuda

Full Text Available The development of novel fertilization treatments, including in vitro fertilization and intracytoplasmic injection, has made pregnancy possible regardless of the level of activity of the spermatozoa; however, the etiology of male-factor infertility is poorly understood. Multiple studies, primarily through the use of transgenic animals, have contributed to a list of candidate genes that may affect male infertility in humans. We examined single nucleotide polymorphisms (SNPs as a cause of male infertility in an analysis of spermatogenesis-specific genes.We carried out the prevalence of SNPs in the coding region of phosphoglycerate mutase 4 (PGAM4 on the X chromosome by the direct sequencing of PCR-amplified DNA from male patients. Using RT-PCR and western blot analyses, we identified that PGAM4 is a functional retrogene that is expressed predominantly in the testes and is associated with male infertility. PGAM4 is expressed in post-meiotic stages, including spermatids and spermatozoa in the testes, and the principal piece of the flagellum and acrosome in ejaculated spermatozoa. A case-control study revealed that 4.5% of infertile patients carry the G75C polymorphism, which causes an amino acid substitution in the encoded protein. Furthermore, an assay for enzymatic activity demonstrated that this polymorphism decreases the enzyme's activity both in vitro and in vivo.These results suggest that PGAM4, an X-linked retrogene, is a fundamental gene in human male reproduction and may escape meiotic sex chromosome inactivation. These findings provide fresh insight into elucidating the mechanisms of male infertility.

Low-fertility rate, market economy, and population control in China.

Science.gov (United States)

Wu, C; Mu, G

1996-01-01

This article discusses the increasingly market-oriented economy in China and the implications for family planning and population control. Modern China has experienced in a few decades a dramatic decline in fertility. Some new issues include whether faster population increase is harmless with a rapidly growing economy, and about whether a large population size offers greater opportunity to attract investment. China adopted its population policies against a specific historical context, and future policies will pertain to new issues. The baby boom of the mid-1970s led to population increase and the impossibility of limiting total population by 2000 to under 1.6 billion. China's huge population size has a significant adverse effect on the survival and development of the nation. Land and natural resources limit the nation's ability to accommodate greater numbers of people. 22% of land is hilly and habitable, but 78.9% is largely uninhabitable basins, mountains, and plateaus. 53% of lands are arid or semi-arid. 20.3% of China's population live under harsh natural conditions, and many are impoverished. 95% of China's population live in the eastern part of the country. Population pressure depletes resources and creates environmental problems. There is pressure on consumption of grain, and labor surpluses threaten modernization and create conflicts between egalitarianism and efficiency. Unemployment insurance and social security are not yet in place to cushion a shift to a competitive market system. Success in rural economic reform is tied to absorbing surplus rural labor. Family planning is critical to improving individual lives, a planned economy, and world responsibility. A market economy in China is likely to modernize attitudes toward reproduction and smooth the transition to a low, stable fertility, but government population control will still be needed. The unanswered question is through what means population will be controlled.

Determination of ''2''1''0Po in fertilizers by electrochemical deposition method

International Nuclear Information System (INIS)

Oezalp, N.; Sac, M.; Tanbay, A.; Yener, G.

2001-01-01

In this study, activities of radioactive polonium and natural radionuclide concentrations in fertilizer most consumed in agricultural lands in Turkey were measured. Fertilizers containing phosphorus and potassium increase yield and quality. But, they contain some radionuclides. These radionuclides dissolve in water and first transport into plants and then transport from plants to humans. In the latest years, artificial fertilizing has replaced natural fertilizing in agriculture. Therefore, fruits and vegetables contain radionuclides those are found in artificial fertilizers. In this study, electrochemical deposition technique with alpha counting method was used for determining the radioactivity level of polonium in fertilizers. Radium, potassium and thorium concentrations were measured by gamma spectrometry. TSP, MAP, DSP,MKP, (15-15-15), (18-18-18), (20-20-20) compost fertilizers consumed at most has been analyzed and the results were evaluated with respect to human health

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).

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

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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.

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...

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.

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)

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.

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 ...

Promoting fertilizer use via controlled release of a bacteria-encapsulated film bag.

Science.gov (United States)

Wu, Chin-San

2010-05-26

A phosphate-solubilizing bacterium ( Burkholderia cepacia isolate) encapsulated in maleic anhydride (MA) grafted onto poly(butylene succinate adipate) (PBSA) and then combined with starch as film bag material (PBSA-g-MA/starch) incubated in a saline solution required approximately 20 days to deplete the starch in the film bags. Thereafter, the cell concentration in the saline solution increased significantly because of the release of cells from the severely destroyed film bags and also their growth by use of depolymerized PBSA-g-MA fragments as a substrate. The incubation proceeded for 60 days, by which time the PBSA-g-MA/starch composite had suffered a >80% weight loss. For practical application, effectiveness of the above-mentioned film bags was demonstrated because it could improve the absorbability of a fertilizer for plants and promote the growth of plants. As a result, it can avoid the accumulation of the phosphate in excess fertilizer that lead to the phenomenon of poor soils. These results demonstrate that PBSA-g-MA/starch can be used to encapsulate cells of an indigenous phosphate-solubilizing bacterium ( B. cepacia isolate) to form a controlled release of bacteria-encapsulated film bag (BEFB). The B. cepacia isolate was able to degrade the film bags material, causing cell release. Biodegradability of the film bags depended upon the type of material used, because the PBSA film bags were also degraded but to a lesser degree. The addition of starch made the film bags more biodegradable. The decrease in intrinsic viscosity was also higher for the starch composite, suggesting a strong connection between the biodegradability and these characteristics. The results suggest that the release of fertilizer-promoted bacteria might be controllable via a suitable film bag material formulation. In addition, this work adopted live bacteria to promote the absorption of phosphate, which is superior to the phosphate used in the traditional way.

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

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Ann M Raiho

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

CONTROL OF SOME PATHOGENS BY USING SPECIAL FOLIAR FERTILIZERS

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I OROIAN

2004-04-01

Full Text Available The present work points out to the interdisciplinary experimental results, obtained in the experimental fields of the Plant Protection and Soil Science Department, as well as at data which stress upon the interdependency between the satisfaction of the trophically needs of the wheat plants and the aggressiveness of the pathogens which cause the disease. The experimental results underline the fact that the attack level expressed through intensity and attack degree is different, both with the “out of root” fertilized variants and with the soil fertilization variants. The conclusions which come off the study of the obtained data point out at the fact that the fertilizer application, no matter the method, determines the growth or the regress of the attack degree. They also have an influence upon the Puccinia striformis f.sp. tritici, Blumeria graminis and, Septoria spp. fungus manifestation.

Effect of gibberellic acid on the quality of sperm and in vitro fertilization outcome in adult male rats

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Mohammadreza Hosseinchi

2014-12-01

Full Text Available Gibberellic acid (GA3 is a group of plant hormones identified in various plants. The aim of this study was to determine the effects of GA3 on sperm parameters and in vitro fertilization (IVF. Fifty six adult male rats were divided into seven groups as, control, treatment and sham. Following 15, 30 and 45 days of GA3 and methanol alcohol (MA administration, rats were euthanized and epididymis tail was transferred to human tubular fluid (HTF medium containing 4 mg mL-1 bovine serum albumin (BSA .Total number of sperms, the percentage of live sperms, immature sperms and sperms with damaged chromatin and IVF were examined. The oocytes were obtained from immature rats after the injection of pregnant mare's serum (PMSG and human chorionic gonadotropin (HCG hormones. Human tubular fluid was used as the fertilization medium and zygotes transferred to fresh 1-cell rat embryos culture medium (mR1ECM to reach the blastocyst stage. This study showed that GA3 could decrease the number of total sperms on days 30 and 45 in treated group comparison with the control and sham groups. Additionally, GA3 increased the immature sperms and sperms with damaged chromatin. The percentage of fertilization, two-cell embryos and blastocyst resulting from the treatment group on days 30 and 45 also decreased and showed significant differences with the control and sham groups (p < 0.05. The results obtained from this study indicated that the oral use of GA3 could reduce the fertility in rats by influencing the sperm number and the quality of sperm’s chromatins.

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

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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.

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

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....

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.

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

Ubiquitin Carboxy-Terminal HydrolaseL3 Correlates with Human Sperm Count, Motility and Fertilization.

Science.gov (United States)

Wang, Meijiao; Yu, Tinghe; Hu, Lina; Cheng, Zhi; Li, Min

2016-01-01

Ubiquitin C-terminal hydrolase L3 (UCHL3) belongs to the group of deubiquitinating enzymes and plays a part in apoptosis of germ cells and the differentiation of spermatocytes into spermatids. However, the exact role of UCHL3 in human spermatogenesis and sperm function remains unknown. Here we examined the level and activity of UCHL3 in spermatozoa from men with asthenozoospermia (A), oligoasthenozoospermia (OA) or normozoospermia (N). Immunofluorescence indicated that UCHL3 was mainly localized in the acrosome and throughout the flagella, and western blotting revealed a lower level in A or OA compared with N (p sperm count, concentration and motility. The UCHL3 level was positively correlated with the normal fertilization rate (FR) and percentage of embryos suitable for transfer/cryopreservation of in vitro fertilization (IVF). The UCHL3 activity was also positively correlated with FR, the percentage of embryos suitable for transfer/cryopreservation and high-quality embryos rate of IVF. Aforementioned correlations were not manifested in intra-cytoplasmic sperm injection (ICSI). These findings suggest that UCHL3 may play a role in male infertility.

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.

Lifestyle factors and reproductive health: taking control of your fertility.

Science.gov (United States)

Sharma, Rakesh; Biedenharn, Kelly R; Fedor, Jennifer M; Agarwal, Ashok

2013-07-16

Approximately 10 to 15% of couples are impacted by infertility. Recently, the pivotal role that lifestyle factors play in the development of infertility has generated a considerable amount of interest. Lifestyle factors are the modifiable habits and ways of life that can greatly influence overall health and well-being, including fertility. Many lifestyle factors such as the age at which to start a family, nutrition, weight, exercise, psychological stress, environmental and occupational exposures, and others can have substantial effects on fertility; lifestyle factors such as cigarette smoking, illicit drug use, and alcohol and caffeine consumption can negatively influence fertility while others such as preventative care may be beneficial. The present literature review encompasses multiple lifestyle factors and places infertility in context for the couple by focusing on both males and females; it aims to identify the roles that lifestyle factors play in determining reproductive status. The growing interest and amount of research in this field have made it evident that lifestyle factors have a significant impact on fertility.

A Multinomial Model of Fertility Choice and Offspring Sex-Ratios in India

OpenAIRE

Rubiana Chamarbagwala; Martin Ranger

2007-01-01

Fertility decline in developing countries may have unexpected demographic consequences. Although lower fertility improves nutrition, health, and human capital investments for surviving children, little is known about the relationship between fertility outcomes and female-male offspring sex-ratios. Particularly in countries with a cultural preference for sons, like India and China, fertility decline may deteriorate the already imbalanced sex-ratios. We use the fertility histories of over 90,00...

Sperm count as a surrogate endpoint for male fertility control.

Science.gov (United States)

Benda, Norbert; Gerlinger, Christoph

2007-11-30

When assessing the effectiveness of a hormonal method of fertility control in men, the classical approach used for the assessment of hormonal contraceptives in women, by estimating the pregnancy rate or using a life-table analysis for the time to pregnancy, is difficult to apply in a clinical development program. The main reasons are the dissociation of the treated unit, i.e. the man, and the observed unit, i.e. his female partner, the high variability in the frequency of male intercourse, the logistical cost and ethical concerns related to the monitoring of the trial. A reasonable surrogate endpoint of the definite endpoint time to pregnancy is sperm count. In addition to the avoidance of the mentioned problems, trials that compare different treatments are possible with reasonable sample sizes, and study duration can be shorter. However, current products do not suppress sperm production to 100 per cent in all men and the sperm count is only observed with measurement error. Complete azoospermia might not be necessary in order to achieve an acceptable failure rate compared with other forms of male fertility control. Therefore, the use of sperm count as a surrogate endpoint must rely on the results of a previous trial in which both the definitive- and surrogate-endpoint results were assessed. The paper discusses different estimation functions of the mean pregnancy rate (corresponding to the cumulative hazard) that are based on the results of sperm count trial and a previous trial in which both sperm count and time to pregnancy were assessed, as well as the underlying assumptions. Sample size estimations are given for pregnancy rate estimation with a given precision.

[Fertility transition in Peru].

Science.gov (United States)

Ferrando, D; Aramburu, C E

1992-12-01

. From 1972 on, the fertility decline spread in the rural sectors and was intensified as a response to the profound economic crisis experienced in Peru from 1975 to the present. Increased contraceptive usage was apparently the most important cause of Peru's fertility decline. Overall prevalence increased from 31% in 1977-78 to 46% in 1986, and use of modern methods by women in union doubled in the same years. Regional fertility differences are correlated strongly to contraceptive prevalence and especially to prevalence of modern methods. The 3 most recent national fertility surveys and a series of more limited surveys suggest that women have an increasingly strong desire to control their fertility. The greatest barriers to use of modern contraception are fears of health effects and lack of knowledge.

Random-start GnRH antagonist for emergency fertility preservation: a self-controlled trial

Directory of Open Access Journals (Sweden)

Checa MA

2015-02-01

Full Text Available Miguel A Checa,1,2 Mario Brassesco,2 Margalida Sastre,1 Manuel Gómez,2 Julio Herrero,3 Laura Marque,3 Arturo Brassesco,2 Juan José Espinós3 1Department of Obstetrics and Gynecology, Parc de Salut Mar, Universitat Autònoma de Barcelona, 2Centro de Infertilidad y Reproducción Humana (CIRH, 3Centro de Reproducción Asistida Sagrada Familia, Clínica Sagrada Familia, Barcelona, Spain Abstract: The aim of this study is to evaluate the feasibility and safety of random-start controlled ovarian hyperstimulation (COH for emergency fertility preservation, regardless of the phase of the menstrual cycle. A self-controlled pilot clinical trial (NCT01385332 was performed in an acute-care teaching hospital and in two private reproductive centers in Barcelona, Spain. Eleven egg donors participated in the study. Two random-start gonadotropin-releasing hormone (GnRH antagonist protocols were assessed in which ganirelix was initiated on either day 10 (protocol B or on day 20 (protocol C of the menstrual cycle and was continued until estradiol levels were below 60 pg/dL. These protocols were compared with a standard protocol (protocol A. The main outcome of interest was the number of metaphase 2 oocytes retrieved. Results from this study show that the number of mature oocytes retrieved was comparable across the different protocols (14.3±4.6 in the standard protocol versus 13.0±9.1 and 13.2±5.2 in protocols B and C, respectively; values expressed as mean ± standard deviation. The mean number of days needed for a GnRH antagonist to lower estradiol levels, as well as the ongoing pregnancy rates, were also similar when protocols B (stimulation in follicular phase and C (stimulation on luteal phase were compared with protocol A (standard stimulation. GnRH antagonists can be effectively used for random-start controlled ovarian hyperstimulation with an ovarian response similar to that of standard protocols, and the antagonists appear suitable for emergency

IVF versus ICSI for the fertilization of in-vitro matured human oocytes.

Science.gov (United States)

Walls, M; Junk, S; Ryan, J P; Hart, R

2012-12-01

Traditional dogma suggests that intracytoplasmic sperm injection (ICSI) should be performed to ensure successful oocyte fertilization in an in-vitro maturation (IVM) cycle. This study postulated that there would be no difference in the fertilization rate when ICSI was compared with IVF. This hypothesis was tested in a randomized trial of IVF versus ICSI in IVM. A total of 150 immature oocytes were collected in eight cycles of IVM for patients diagnosed with polycystic ovarian syndrome (PCOS). Patients were primed with minimal FSH before transvaginal oocyte aspiration. Sibling oocytes were inseminated by 50% IVF and 50% ICSI. There was no significant difference in fertilization, useable or total blastocyst development between the two insemination technique groups. Clinical pregnancy results for combined fresh and cryopreserved transfers were identical between the two insemination techniques with a total of two fresh and five cryopreserved IVF-inseminated embryos resulting in three clinical pregnancies (42.9%) and five fresh and two cryopreserved ICSI-derived embryos resulting in three clinical pregnancies (42.9%). This research has shown IVF to be a legitimate fertilization technique for IVM oocytes in PCOS patients and provides a greater awareness of the use of a fertilization method previously not utilized with IVM. In-vitro maturation (IVM) is an alternative treatment method to traditional IVF. Due to the minimal use of stimulating hormones in this treatment, IVM has a lower risk of ovarian hyperstimulation syndrome, it can be used for fertility preservation in cancer patients and it is more cost conservative. Early research into the effects of IVM showed a hardening effect on the membrane surrounding the egg (the zona pellucida). It was initially believed that, to overcome this hardening in order to allow the egg to be fertilized, spermatozoa would need to be injected into the egg using intracytoplasmic sperm injection. Due to recent advances in hormonal

Fertility regulation as identity maintenance: Understanding the social aspects of birth control.

Science.gov (United States)

Marston, Cicely; Renedo, Alicia; Nyaaba, Gertrude Nsorma

2018-02-01

We take a dialogical approach to exploring fertility regulation practices and show how they can maintain or express social identity. We identify three themes in educated Ghanaian women's accounts of how they navigate conflicting social demands on their identity when trying to regulate fertility: secrecy and silence - hiding contraception use and avoiding talking about it; tolerating uncertainty - such as using unreliable but more socially acceptable contraception; and wanting to be fertile and protecting menses. Family planning programmes that fail to tackle such social-psychological obstacles to regulating fertility will risk reproducing social spaces where women struggle to claim their reproductive rights.

Immunocontraceptives: New Approaches to Fertility Control

Directory of Open Access Journals (Sweden)

Kiranjeet Kaur

2014-01-01

Full Text Available The rapidly increasing global population has bowed the attention of family planning and associated reproductive health programmes in the direction of providing a safe and reliable method which can be used to limit family size. The world population is estimated to exceed a phenomenal 10 billion by the year 2050 A.D., thus presenting a real jeopardy of overpopulation with severe implications for the future. Despite the availability of contraceptive methods, there are over one million elective abortions globally each year due to unintended pregnancies, having devastating impact on reproductive health of women worldwide. This highlights the need for the development of newer and improved contraceptive methods. A novel contraceptive approach that is gaining substantial attention is “immunocontraception” targeting gamete production, gamete outcome, or gamete function. Amongst these, use of sperm antigens (gamete function seems to be an exciting and feasible approach. However, the variability of immune response and time lag to attain titer among vaccinated individuals after active immunization has highlighted the potential relevance of preformed antibodies in this league. This review is an attempt to analyze the current status and progress of immunocontraceptive approaches with respect to their establishment as a future fertility control agent.

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

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

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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

Chemicals agents and human male fertility: Review of the past thirty years literature; Sostanze chimiche e infertilita` maschile: Rassegna degli studi condotti negli ultimi trenta anni

Energy Technology Data Exchange (ETDEWEB)

Traina, Maria Elsa; Urbani, Elisabetta [Istituto Superiore di Sanita`, Rome (Italy). Lab. di Igiene Ambientale; Petrelli, Grazia; Pasquali, Massimo; Pace, Francesca [Istituto Superiore di Sanita`, Rome (Italy). Lab. di Epidemiologia e Biostatistica

1997-03-01

The effects of several industrial and environmental pollutants on the male reproductive system are known from animal studies, but to date the impact on human fertility is still scarcely documented by epidemiological studies. The literature of the past thirty years on the adverse effects of occupational chemical factors on human male fertility is reviewed. Eighty-nine studies have been analysed with the purpose to identify the substances and/or the working categories investigated and to evaluate the methods used. Since 1977 the interest has been focused on the human exposures to 1,2-dibromochloropropane, a powerful spermatotoxic agent, but a consistent number of studies was also related to other active ingredients of pesticides (lindane, carbaryl, 2,4-dichlorofenoxiacetic acid), solvents (glycol ethers, carbon disulfide) and heavy metals (lead, cadmium). Among the indicators used in these studies to evaluate the effects on male fertility, the seminal parameters are analysed in 67 % of the reports; blood hormonal tests are done in 54 % of the cases. The literature suggests that further epidemiological studies need to be conducted in other working categories; more attention should be paid to the sensitivity and biological significance of the male reproductive parameters used in human studies.

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)

The Trojan Female Technique for pest control: a candidate mitochondrial mutation confers low male fertility across diverse nuclear backgrounds in Drosophila melanogaster.

Science.gov (United States)

Dowling, Damian K; Tompkins, Daniel M; Gemmell, Neil J

2015-10-01

Pest species represent a major ongoing threat to global biodiversity. Effective management approaches are required that regulate pest numbers, while minimizing collateral damage to nontarget species. The Trojan Female Technique (TFT) was recently proposed as a prospective approach to biological pest control. The TFT draws on the evolutionary hypothesis that maternally inherited mitochondrial genomes are prone to the accumulation of male, but not female, harming mutations. These mutations could be harnessed to provide trans-generational fertility-based control of pest species. A candidate TFT mutation was recently described in the fruit fly, Drosophila melanogaster, which confers male-only sterility in the specific isogenic nuclear background in which it is maintained. However, applicability of the TFT relies on mitochondrial mutations whose male-sterilizing effects are general across nuclear genomic contexts. We test this assumption, expressing the candidate TFT-mutation bearing haplotype alongside a range of nuclear backgrounds and comparing its fertility in males, relative to that of control haplotypes. We document consistently lower fertility for males harbouring the TFT mutation, in both competitive and noncompetitive mating contexts, across all nuclear backgrounds screened. This indicates that TFT mutations conferring reduced male fertility can segregate within populations and could be harnessed to facilitate this novel form of pest control.

Phosphate fertilizer influence on {sup 238} U content in vegetables

Energy Technology Data Exchange (ETDEWEB)

Lauria D, C.; Rodrigues S, J.I. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN), Av. Salvador Allende s/n, Rio de Janeiro-RJ (Brazil); Ribeiro, F.C.A. [Centro Regional de Ciencias Nucleares (CRCN/CNEN) Av. Prof. Luiz Freire 200 Cidade Universitaria Recife-PE (Brazil)]. e-mail: dejanira@ird.gov.br

2006-07-01

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 {sup 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 {sup 238} U have been carried out by conventional fluorimetric method. The geometric mean of {sup 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

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.

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, ...

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

FERTILIZING INFLUENCE TOWARDS GROWTH AND FRUIT CROPS OF COCOA

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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.

Sexuality and fertility in men with hypospadias; improved outcome.

Science.gov (United States)

Örtqvist, L; Fossum, M; Andersson, M; Nordenström, A; Frisén, L; Holmdahl, G; Nordenskjöld, A

2017-03-01

The aim of this study was to investigate sexual function and fertility in adult men born with hypospadias. Patients born with hypospadias, age-matched controls, and a group of circumcised men completed a questionnaire constructed to reflect their psychosexual situation and fertility. Core gender identity, sexual orientation, and gender role behavior was also assessed. 167 patients [63% distal, 24% mid shaft and 13% proximal, mean age 34 (19-54) years], 169 controls from the general population [mean age 33 (19-48) years] and 47 controls circumcised because of phimosis (mean age 26 [19-44]) participated and completed the questionnaire. There were no differences in having a partner, reported fertility, age at sexarche (mean age 17.8), number of sex partners or sexual interest between the patients and controls. More patients than controls reported anejaculation. Reported glanular sensitivity was lower in hypospadias patients and circumcised controls compared with non-circumcised controls. The odds of being satisfied with their sexual life increased with a higher penile perception score in patients (OR = 1.54, p = 0.01). There was no association with penile length. Sexual orientation, core gender identity and gender role behavior were sex-typical in both patients and controls. Patients with proximal hypospadias had a lower reported fertility, experienced anejaculation more often, and were less satisfied with their sexual life. Men born with hypospadias have a good long-term outcome concerning sexual function and fertility. Men born with proximal hypospadias have a more impaired outcome concerning both sexual function and fertility. As satisfaction with genital appearance is important for sexual life satisfaction, clinical, and psychological follow-up into adulthood is especially important in boys born with proximal hypospadias. © 2016 American Society of Andrology and European Academy of Andrology.

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.

Intrauterine fertilization capsules--a clinical trial

DEFF Research Database (Denmark)

Lenz, S; Lindenberg, S; Sundberg, K

1991-01-01

Treatment of 26 women with tubal infertility was attempted using intrauterine capsules loaded with oocytes and spermatozoa. The stimulation protocol was as used for in vitro fertilization and embryo transfer and consisted of short-term use of Buserelin, human menopausal gonadotropin, and human...... and piston from an intrauterine device. Six complete capsules and parts of two other capsules were expelled. None of the women became pregnant, compared with a pregnancy rate of 21% per aspiration following in vitro fertilization and embryo transfer during the same period....... chorionic gonadotropin. Oocytes were collected by ultrasonically guided transvaginal aspiration, and spermatozoa were prepared by swim-up technique. The gametes were placed in agar capsules 4 hr after oocyte collection, and the capsules were introduced to the uterine fundus using an insertion tube...

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

Nanocomposites for controlled release of nitrogen fertilizer;Nanocompositos para liberacao controlada de fertilizantes nitrogenados

Energy Technology Data Exchange (ETDEWEB)

Silva, Viviane J.M. da; Visconte, Leila L.Y. [Universidade Federal do Rio de Janeiro (IMA/UFRJ), RJ (Brazil). Inst. de Macromoleculas Profa. Eloisa Mano; Matos, Talita S.; Lima, Erica S.A.; Polidoro, Jose Carlos [EMBRAPA Solos, RJ (Brazil); Nascimento, Regina Sandra V. [Universidade Federal do Rio de Janeiro (IQ/UFRJ), RJ (Brazil). Inst. de Quimica

2009-07-01

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)

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

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).

Use of homeopathic drugs in combination with fertilizers for the control of root rot fungi

International Nuclear Information System (INIS)

Hanif, A.; Dawar, S.

2015-01-01

This study was conducted to evaluate the fungicidal effectiveness of homeopathic drugs in combination with fertilizers on the growth production and controlling of root rot fungi. Seeds treated with homeopathic drugs in addition of phosphorous and nitrogen fertilizers as soil amendment showed significant inhibitory effect on fungal growth as well as improved the plant growth. Remarkable control of root infecting fungi was shown by the seeds treated with Thuja occidentalis and Arnica montana at rate of 75 percentage v/v concentration and soil amended with urea at rate of 0.1 percentage w/w but greater increased in plant growth was observed by urea at rate of 0.01 percentage in the tested plants viz. mung bean, mash bean, sunflower and okra. Whereas, when A. montana and T. occidentalis at rate of 75 percentage v/v concentration along with the addition of DAP at rate of 0.01 and 0.1 percentage w/w respectively showed maximum suppression of Fusarium spp, R. solani and M. phaseolina and enhanced the plant height and weight followed by A. montana and T. occidentalis at rate of 50 percentage v/v concentration respectively showed a maximum control of root rot fungi and also strengthened the crop plant for better growth. (author)

Determination of the uranium content in phosphate fertilizers by the fission track registration technique

International Nuclear Information System (INIS)

Rocha, A.C.S. da.

1983-01-01

The application of fission track registration technique (SSNTD) to determine the uranium contents in phosphate fertilizers is dealt with. Samples were prepared by the wet method and the detector used was Makrofol Kg 10μm thick. The determination of uranium in phosphate fertilizer industry is of considerable interest in environmental control. The roots of vegetables tend to absorb and accumulate uranium form soil and so the human body could be contaminated. The phosphate fertilizers were originated from the phosphate-rich apatite deposits located in the high naturally radioactive areas of Araxa and Tapira in the state of Minas Gerais, Brazil. The results obtained ranged from 11.1 to 100ppm of uranium with a total error from 8.2 to 15.7%. The thorium contributions to the total track counting were discounted, though the actual concentrations of thorium in the samples were not determined. (Author) [pt

New advances in ovarian autotransplantation to restore fertility in cancer patients.

Science.gov (United States)

Salama, Mahmoud; Woodruff, Teresa K

2015-12-01

Human ovary autotransplantation is a promising option for fertility preservation of young women and girls undergoing gonadotoxic treatments for cancer or some autoimmune diseases. Although experimental, it resulted in at least 42 healthy babies worldwide. According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic literature review was performed for all relevant full-text articles published in English from 1 January 2000 to 01 October 2015 in PubMed to explore the latest clinical and research advances of human ovary autotransplantation. Human ovary autotransplantation involves ovarian tissue extraction, freezing/thawing, and transplantation back into the same patient. Three major forms of human ovary autotransplantation exist including (a) transplantation of cortical ovarian tissue, (b) transplantation of whole ovary, and (c) transplantation of ovarian follicles (artificial ovary). According to the recent guidelines, human ovary autotransplantation is still considered experimental; however, it has unique advantages in comparison to other options of female fertility preservation. Human ovary autotransplantation (i) does not need prior ovarian stimulation, (ii) allows immediate initiation of cancer therapy, (iii) can restore both endocrine and reproductive ovarian functions, and (iv) may be the only fertility preservation option suitable for prepubertal girls or for young women with estrogen-sensitive malignancies. As any other fertility preservation option, human ovary autotransplantation has both advantages and disadvantages and may not be feasible for all cases. The major challenges facing this option are how to avoid the risk of reintroducing malignant cells and how to prolong the lifespan of ovarian transplant as well as how to improve artificial ovary results.

Establishment of a high-resolution 2-D reference map of human spermatozoal proteins from 12 fertile sperm-bank donors.

Science.gov (United States)

Li, Ling-Wei; Fan, Li-Qing; Zhu, Wen-Bing; Nien, Hong-Chuan; Sun, Bo-Lan; Luo, Ke-Li; Liao, Ting-Ting; Tang, Le; Lu, Guang-Xiu

2007-05-01

To extend the analysis of the proteome of human spermatozoa and establish a 2-D gel electrophoresis (2-DE) reference map of human spermatozoal proteins in a pH range of 3.5-9.0. In order to reveal more protein spots, immobilized pH gradient strips (24 cm) of broad range of pH 3-10 and the narrower range of pH 6-9, as well as different overlapping narrow range pH immobilized pH gradient (IPG) strips, including 3.5-4.5, 4.0-5.0, 4.5-5.5, 5.0-6.0 and 5.5-6.7, were used. After 2-DE, several visually identical spots between the different pH range 2-D gel pairs were cut from the gels and confirmed by mass spectrometry and used as landmarks for computer analysis. The 2-D reference map with pH value from 3.5 to 9.0 was synthesized by using the ImageMaster analysis software. The overlapping spots were excluded, so that every spot was counted only once. A total of 3872 different protein spots were identified from the reference map, an approximately 3-fold increase compared to the broad range pH 3-10 IPG strip (1306 spots). The present 2-D pattern is a high resolution 2-D reference map for human fertile spermatozoal protein spots. A comprehensive knowledge of the protein composition of human spermatozoa is very meaningful in studying dysregulation of male fertility.

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

MicroRNAs: From Female Fertility, Germ Cells, and Stem Cells to Cancer in Humans

Directory of Open Access Journals (Sweden)

Irma Virant-Klun

2016-01-01

Full Text Available MicroRNAs are a family of naturally occurring small noncoding RNA molecules that play an important regulatory role in gene expression. They are suggested to regulate a large proportion of protein encoding genes by mediating the translational suppression and posttranscriptional control of gene expression. Recent findings show that microRNAs are emerging as important regulators of cellular differentiation and dedifferentiation, and are deeply involved in developmental processes including human preimplantation development. They keep a balance between pluripotency and differentiation in the embryo and embryonic stem cells. Moreover, it became evident that dysregulation of microRNA expression may play a fundamental role in progression and dissemination of different cancers including ovarian cancer. The interest is still increased by the discovery of exosomes, that is, cell-derived vesicles, which can carry different proteins but also microRNAs between different cells and are involved in cell-to-cell communication. MicroRNAs, together with exosomes, have a great potential to be used for prognosis, therapy, and biomarkers of different diseases including infertility. The aim of this review paper is to summarize the existent knowledge on microRNAs related to female fertility and cancer: from primordial germ cells and ovarian function, germinal stem cells, oocytes, and embryos to embryonic stem cells.

[Hydatid fertility and protoscolex viability in humans: study of 78 hydatid samples collected between 2005 and 2012 and analyzed at the parasitology laboratory of the Mustapha University Hospital Center of Algiers].

Science.gov (United States)

Zait, H; Boulahbel, M; Zait, F; Achir, I; Guerchani, M T; Chaouche, H; Ladjadje, Y; Hamrioui, B

2013-05-01

An analysis at the Mustapha University Hospital Center of Algiers examined 78 hydatid samples collected between 2005 and 2012 to determine the fertility rate of metacestodes and the viability of protoscolices. The fertility rate of the hydatid cysts in humans was 88.4% and the protoscolex viability rate 74.5%. The fertility and viability rates found here are high, despite the use of scolicides.

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.

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

The impact of freedom on fertility decline.

Science.gov (United States)

Campbell, Martha M; Prata, Ndola; Potts, Malcolm

2013-01-01

Although fertility decline often correlates with improvements in socioeconomic conditions, many demographers have found flaws in demographic transition theories that depend on changes in distal factors such as increased wealth or education. Human beings worldwide engage in sexual intercourse much more frequently than is needed to conceive the number of children they want, and for women who do not have access to the information and means they need to separate sex from childbearing, the default position is a large family. In many societies, male patriarchal drives to control female reproduction give rise to unnecessary medical rules constraining family planning (including safe abortion) or justifying child marriage. Widespread misinformation about contraception makes women afraid to adopt modern family planning. The barriers to family planning can be so deeply infused that for many women the idea of managing their fertility is not considered an option. Conversely, there is evidence that once family planning is introduced into a society, then it is normal consumer behaviour for individuals to welcome a new technology they had not wanted until it became realistically available. We contend that in societies free from child marriage, wherever women have access to a range of contraceptive methods, along with correct information and backed up by safe abortion, family size will always fall. Education and wealth can make the adoption of family planning easier, but they are not prerequisites for fertility decline. By contrast, access to family planning itself can accelerate economic development and the spread of education.

An Evaluation of the Historical Importance of Fertility and Its Reflection in Ancient Mythology.

Science.gov (United States)

Behjati-Ardakani, Zohreh; Akhondi, Mohammad Mehdi; Mahmoodzadeh, Homa; Hosseini, Seyed Hasan

2016-01-01

Myths are reflective of human concerns and needs during ancient times. By reviewing them, it turns out that many human problems today, have a historical background. Among the main themes of ancient mythologies, fertility and reproduction have various representations in ancient civilizations. The purpose of this paper was to review myths and common symbols of fertility and reproduction in ancient civilizations and evaluate the reasons of their continuous importance in different cultures. The data in this review study was obtained by scrutinizing the related literature. The gathered data indicated the multiplicity and variety of fertility symbols in ancient myths. Most ancient fertility symbols were inspired by the nature and some of them like earth and water were common in mythology of different civilizations. Therefore, the symbols consolidate the concept of conformity between human reproductive concerns and the nature's necessities.

Challenges of Obtaining Evidence-Based Information Regarding Medications and Male Fertility.

Science.gov (United States)

Drobnis, Erma Z; Nangia, Ajay K

2017-01-01

In the clinic, the existing literature is insufficient to counsel our infertile men on medication use. Most studies have flaws that limit their application to evidence-based practice. In this chapter, we discuss the limitations of the current literature and the challenges to designing more useful studies. Among the most important weaknesses of existing studies is lack of power; that is, too few men are included to draw conclusions about the existence and size of medication effects. Adequate power is particularly important when confirming an absence of medication effect. Bias is also a problem in most studies. Early studies were rarely randomized, placebo-controlled, or blinded; a common example is patients receiving different medication regimes based on the severity of their symptoms-making it impossible to attribute differences between treated and untreated men to the medications. Additional bias is introduced by failing to include other factors that influence the outcome in the experimental design. A uniform population amenable to randomization and placebo-control are experimental species, and useful information has been gained from these models. However, application to humans is limited by differences from other species in route of drug administration, absorption of the drug, concentration in the male genital tract tissues, and genital tract physiology. To a lesser degree, there is variation among individual men in their response to drugs. In addition, drugs in the same class may have different effects, limiting the applicability of data across drugs of a single class. Complicating matters further, a toxic medication may seem to improve fertility endpoints by improving a disease condition that diminishes fertility. Finally, drug interactions have not been studied, and actual fertility data (pregnancy/fecundity) in humans are rare. A healthy dose of skepticism is warranted when evaluating studies of medications and male reproductive health.

The control of radioactivity in the working environment in the factories for production of phosphate fertilizers

International Nuclear Information System (INIS)

Ajdacic, B.N.; Gnjatovic, S.S.; Vujovic, P.V.

1980-01-01

The results of dosimetric control in factories for the production of phosphoric acid and phosphate fertilizers in Serbia, and of the measurement of the total beta radioactivity of samples collected in these factories, are presented. An increase in the radiation dose, even up to 1000 times background, has been found at certain places in the plant. These results serve as a basis for conclusions on the existence, variation and collection of the radioactive component in particular phases of the technological process for the production of phosphate fertilizers. An attempt is made on the basis of the results obtained in three plants to evaluate the degree of danger in the working environment and in the area surrounding the factories and to propose protective measures. (Author)

Fertility, kinship and the evolution of mass ideologies.

Science.gov (United States)

David-Barrett, Tamas; Dunbar, Robin I M

2017-03-21

Traditional human societies are organised around kinship, and use kinship networks to generate large scale community projects. This is made possible by a combination of linguistic kin recognition, a uniquely human trait, which is mediated by the reliability of kin as collaborators. When effective fertility falls, this results in two simultaneous effects on social networks: there are fewer kin that can be relied on, and the limiting effect of the local kin-clustering becomes stronger. To capture this phenomenon, we used a model of kinship lineages to build populations with a range of fertility levels combined with a behavioural synchrony model to measure the efficiency of collective action generated on kin networks within populations. Our findings suggest that, whenever effective cooperation depends on kinship, falling fertility creates a crisis when it results in too few kin to join the community project. We conclude that, when societies transition to small effective kin networks, due to falling fertility, increased relative distance to kin due to urbanisation or high mortality due to war or epidemics, they will be able to remain socially cohesive only if they replace disappearing kin networks with quasi-kin alternatives based on membership of guilds or clubs. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

Recent fertility trends in industrialized countries: toward a fluctuating or a stable pattern?

Science.gov (United States)

Day, L H

1995-09-01

The conclusion of this analysis of fertility trends in industrialized countries is that future trends will be evident from accurate data and the inclusion of causal factors such as religion, ethnicity, migration status, marital status, employment status, neighborhood residence, or housing type. Period fertility measures are considered to be unreliable but useful as indicators of potential future changes in fertility. The expectation is that developed countries with low birth rates will have greater fluctuations than trends. Current patterns of fertility in developed countries are thought to have occurred due to substantial control over both the number and the timing of fertility. Patterns in the recent past have reflected further decline, an end to decline and a continued increase, or fluctuation. The most widespread pattern is continued increase following a period of low fertility. This pattern is in evidence in almost every country of northern and western Europe, Canada, the United States, and New Zealand. Countries with continued declines include Japan and eastern and southern European countries, which were the last to experience declines to replacement levels. Countries with fluctuating patterns include Norway, Sweden, and Switzerland. Countries with greater fluctuations include Belgium, Iceland, the former West Germany, the Netherlands, and Poland. The argument is made to not count these patterns as fluctuations due to 1) the similarity in magnitude, timing, and direction; 2) the small changes after the low was reached; and 3) their appearance everywhere at the same time. Stability of rates in the future appears to be a reasonable prospect due to the greater openness about human sexuality and the wider roles for women. Changes have occurred in attitudes about family size in the direction of smaller families, and the range in family size has narrowed considerably. Potential increases may occur due to a new emphasis on family and parenthood, the diminished

The secretory products of Trichomonas vaginalis decrease fertilizing capacity of mice sperm in vitro

Science.gov (United States)

Roh, Jaesook; Lim, Young-Su; Seo, Min-Young; Choi, Yuri; Ryu, Jae-Sook

2015-01-01

Trichomonas vaginalis infection is one of the most prevalent sexually transmitted infections in humans and is now recognized as an important cause of infertility in men. There is little information about the effect of extracellular polymeric substances (EPS) from T. vaginalis on sperm, but previous reports do not provide a conclusive description of the functional integrity of the sperm. To investigate the impact of EPS on the fertilizing capacity of sperm, we assessed sperm motility, acrosomal status, hypo-osmotic swelling, and in vitro fertilization rate after incubating the sperm with EPS in vitro using mice. The incubation of sperm with EPS significantly decreased sperm motility, viability, and functional integrity in a concentration and time-dependent manner. These effects on sperm quality also resulted in a decreased fertilization rate in vitro. This is the first report that demonstrates the direct negative impact of the EPS of T. vaginalis on the fertilization rate of sperm in vitro. However, further study should be performed using human sperm to determine if EPS has similar negative impact on human sperm fertilizing capacity in vitro. PMID:25578937

Optimal life-cycle profiles of fertility and labor supply.

Science.gov (United States)

Moffitt, R

1984-01-01

A model of life cycle fertility is developed using the language and framework of optimal control theory. The chief characteristic of children that distinguishes them from other consumer durables is, in the language of the optimal growth theory, the "irreversibility of investment." As the good does not depreciate in the ordinary sense, the stock must be monotonically nondecreasing over time. The optimal profile of fertility is, for this reason, characterized by the same type of "bang-bang" behavior found in many optimal growth problems. Yet, the fertility decision is complicated considerably by several other factors. Chief among these is the intrinsic relation to the labor-supply decision, for having children implies inevitable constraints on the mother's or father's time. Thus, optimal labor-supply decisions also must be considered. The model is developed in stages, proceeding from very simple to the more complex models. 1 section introduces the impact of fertility on the future demands for home time. It is shown that optimal fertility profiles follow turnpike paths similar to those in the growth-theory literature. A subsequent section introduces labor-supply and human-captial considerations. As the models become more complex, solutions become harder to derive and are often only outlined. The analysis provides some theoretical basis for expecting certain shapes of the life-cycle profiles of fertility, labor supply, and wages. Fertility profiles may be of 2 shapes--one beginning at a high rate, falling to a lower rate, then to zero; and one beginning at zero, rising to a moderate rate, then falling back down to zero. Labor supply profiles can be of a number of different shapes, but the impact of childbearing is to lower hours worked during the early childrearing period. As the children mature, hours worked rise (or at least fall more slowly) as home time responsibilities lessen, although the level to which they rise will probably be lower than before the 1st birth

Slimmer or fertile? Pharmacological mechanisms involved in reduced sperm quality and fertility in rats exposed to the anorexigen sibutramine.

Directory of Open Access Journals (Sweden)

Cibele S Borges

Full Text Available Sperm acquire motility and fertility capacity during epididymal transit, under the control of androgens and sympathetic innervations. It is already known that the acceleration of epididymal sperm transit time can lead to lower sperm quality. In a previous work we showed that rats exposed to the anorexigen sibutramine, a non-selective serotonin-norepinephrine reuptake inhibitor, presented faster sperm transit time, lower epididymal sperm reserves and potentiation of the tension of epididymal duct to norepinephrine exposed acutely in vitro to sibutramine. In the present work we aimed to further investigate pharmacological mechanisms involved in these alterations and the impact on rat sperm quality. For this, adult male Wistar rats were treated with sibutramine (10 mg/kg/day or vehicle for 30 days. Sibutramine decreased final body, seminal vesicle, ventral prostate and epididymal weights, as well as sperm transit time in the epididymal cauda. On the contrary of the in vitro pharmacological assays, in which sibutramine was added directly to the bath containing strips of distal epididymal cauda, the ductal tension was not altered after in vivo sub-chronic exposure to sibutramine. However, there is pharmacological evidence that the endogenous epididymal norepinephrine reserves were reduced in these animals. It was also shown that the decrease in prostate weight can be related to increased tension developed of the gland, due to sibutramine sympathomimetic effects. In addition, our results showed reduced sperm quality after in utero artificial insemination, a more sensitive procedure to assess fertility in rodents. The epididymal norepinephrine depletion exerted by sibutramine, associated with decreases in sperm transit time, quantity and quality, leading to reduced fertility in this experimental model, reinforces the concerns about the possible impact on fertility of man taking sibutramine as well as other non-selective serotonin

Slimmer or fertile? Pharmacological mechanisms involved in reduced sperm quality and fertility in rats exposed to the anorexigen sibutramine.

Science.gov (United States)

Borges, Cibele S; Missassi, Gabriela; Pacini, Enio S A; Kiguti, Luiz Ricardo A; Sanabria, Marciana; Silva, Raquel F; Banzato, Thais P; Perobelli, Juliana E; Pupo, André S; Kempinas, Wilma G

2013-01-01

Sperm acquire motility and fertility capacity during epididymal transit, under the control of androgens and sympathetic innervations. It is already known that the acceleration of epididymal sperm transit time can lead to lower sperm quality. In a previous work we showed that rats exposed to the anorexigen sibutramine, a non-selective serotonin-norepinephrine reuptake inhibitor, presented faster sperm transit time, lower epididymal sperm reserves and potentiation of the tension of epididymal duct to norepinephrine exposed acutely in vitro to sibutramine. In the present work we aimed to further investigate pharmacological mechanisms involved in these alterations and the impact on rat sperm quality. For this, adult male Wistar rats were treated with sibutramine (10 mg/kg/day) or vehicle for 30 days. Sibutramine decreased final body, seminal vesicle, ventral prostate and epididymal weights, as well as sperm transit time in the epididymal cauda. On the contrary of the in vitro pharmacological assays, in which sibutramine was added directly to the bath containing strips of distal epididymal cauda, the ductal tension was not altered after in vivo sub-chronic exposure to sibutramine. However, there is pharmacological evidence that the endogenous epididymal norepinephrine reserves were reduced in these animals. It was also shown that the decrease in prostate weight can be related to increased tension developed of the gland, due to sibutramine sympathomimetic effects. In addition, our results showed reduced sperm quality after in utero artificial insemination, a more sensitive procedure to assess fertility in rodents. The epididymal norepinephrine depletion exerted by sibutramine, associated with decreases in sperm transit time, quantity and quality, leading to reduced fertility in this experimental model, reinforces the concerns about the possible impact on fertility of man taking sibutramine as well as other non-selective serotonin-norepinephrine reuptake inhibitors

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

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

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...

Income inequality and adolescent fertility in low-income countries.

Science.gov (United States)

Castro, Ruben; Fajnzylber, Eduardo

2017-09-28

: The well-known socioeconomic gradient in health does not imply that income inequality by itself has any effect on well-being. However, there is evidence of a positive association between income inequality and adolescent fertility across countries. Nevertheless, this key finding is not focused on low-income countries. This study applies a multilevel logistic regression of country-level adolescent fertility on country-level income inequality plus individual-level income and controls to the Demographic and Health Surveys data. A negative association between income inequality and adolescent fertility was found among low-income countries, controlling for income (OR = 0.981; 95%CI: 0.963-0.999). Different measures and different subsamples of countries show the same results. Therefore, the international association between income inequality and adolescent fertility seems more complex than previously thought.

Current status of fertility control methods in India

Indian Academy of Sciences (India)

Use of the condom increased to 3.1% from 2.4%. ... Current efforts in India to develop a male contraceptive are mainly directed towards ... the existing range of contraceptive methods available in the National Family Planning Programme. ... long acting, relatively easily removed and fertility returns rapidly after their removal.

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.

Environmental and health impacts of successive mineral fertilization in Egypt

Energy Technology Data Exchange (ETDEWEB)

Abdelhafez, Ahmed A. [Soils, Water and Environment Research Institute (SWERI), Agricultural Research Center (ARC), Giza (Egypt); Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai (China); Abbas, Hassan H.; Abd-El-Aal, Rafat S. [Faculty of Agriculture, Benha University (Egypt); Kandil, Nabil F. [Soils, Water and Environment Research Institute (SWERI), Agricultural Research Center (ARC), Giza (Egypt); Li, Jianhua [Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai (China); Mahmoud, Wahballah [Center of Excellence of Biotechnology Research, King Saud University, Riyadh (Saudi Arabia)

2012-04-15

Excessive amounts of mineral fertilizers are unnecessarily applied to agricultural soils in Egypt to increase crop yield. The current study aims at assessing the impacts of fertilization with different mineral fertilizers for different cultivation periods on the accumulation of heavy metals in soils and plants grown thereon. In addition, human risks resulted due to the exposure to these metal ions through ingestion, and dermal routes were evaluated. Soil and plant samples were collected from several locations in El-Behira Governorate, Egypt and their heavy metal contents were measured. The result indicated that there is a continuous accumulation of heavy metals in the soils and the plants grown thereon. Calculation of the hazard index (HI) revealed that humans, especially children, have a potential health risk for both Pb and Cd, which have levels greater than the safe level (1). Finally, the obtained results showed that the continuous application of mineral fertilizers containing high levels of heavy metals pose a potential health threat. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

ANTI-FERTILITY EFFECTS OF SOME PLANTS USED BY THE STREET HERBAL VENDORS FOR BIRTH CONTROL

OpenAIRE

Sinha, Rajiv K.; Nathawat, G.S.

1989-01-01

The Herbal Vendors are the descendants of ancient mobile tribal medicine men. Now –a –days they sell crude Herbal Drugs on the streets of India. They have knowledge of medicinal plants – a skill which inherited from their forefathers. Also they are aware of the medicinal value of certain locally growing plants which are administered and control fertility and, do help family planning.

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...

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...

Can human populations be stabilized?

Science.gov (United States)

Warren, Stephen G.

2015-02-01

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

Poverty, Fertility and Child Labor: Does Demand Theory of Fertility Matter? An Exploratory Study in India

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Gargi Bhattacharya

2013-07-01

Full Text Available It is hypothesized that fertility, poverty and child labor are jointly determined variables; neither can be assumed to be an independent determinant of the other. In a simultaneous equation framework, we find that demand theory of fertility does hold good even at the lower level of income where the females are compelled to go outside home for cash in order to avoid destitute and they prefer less number of children. Therefore, in order to regulate fertility in India, one can suggest increasing female employment opportunity at the informal sector, since formal sector job is severely restricted in India. It is observed that child labor is caused by lower health status and poor human capital investment. Thus, if we increase the per capita social sector expenditure on education and healthcare, it directly augments enrollment of the children in school. Since health and education is treated as complementary to each other, a rise in social sector investment has some spillover benefits to the society.

Cardiovascular Risk Following Fertility Therapy: Systematic Review and Meta-Analysis.

Science.gov (United States)

Dayan, Natalie; Filion, Kristian B; Okano, Marisa; Kilmartin, Caitlin; Reinblatt, Shauna; Landry, Tara; Basso, Olga; Udell, Jacob A

2017-09-05

The longer term cardiovascular effects of fertility therapy are unknown. The aim of this study was to summarize data linking fertility therapy with subsequent cardiovascular outcomes. We systematically searched published reports for studies addressing the question "does fertility therapy increase the risk of longer term cardiovascular outcomes?" We included: 1) human studies; 2) case control, cohort, or randomized designs with 3) exposure to fertility therapy and 4) cardiovascular outcomes clearly reported; 5) presence of comparison group; 6) minimum 1-year follow-up; and 7) adjustment for age. Two independent reviewers screened abstracts, titles, and full texts, and assessed study quality. We used the DerSimonian and Laird random-effects models to pool hazard ratios (HRs) with 95% confidence intervals (CIs) of the following outcomes: acute cardiac event; stroke; venous thromboembolism; hypertension; and diabetes mellitus, comparing women who received fertility therapy with those who did not. Six observational studies met inclusion criteria including 41,910 women who received fertility therapy and 1,400,202 women who did not. There was no increased risk of a cardiac event (pooled HR: 0.91; 95% CI: 0.67 to 1.25; I 2  = 36.6%), or diabetes mellitus (pooled HR: 0.93; 95% CI: 0.87 to 1.001; I 2  = 0%). Results were not pooled for hypertension (I 2  = 95.0%) and venous thromboembolism (I 2  = 82.3%). There was a trend toward higher risk of stroke (pooled HR: 1.25; 95% CI: 0.96 to 1.63; I 2  = 0%). The small number of studies and significant heterogeneity precludes definitive reassurance about the longer term cardiovascular safety of these treatments, particularly stroke. Future studies are needed to address ongoing knowledge gaps in this area. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Income inequality and adolescent fertility in low-income countries

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Ruben Castro

2017-09-01

Full Text Available Abstract: The well-known socioeconomic gradient in health does not imply that income inequality by itself has any effect on well-being. However, there is evidence of a positive association between income inequality and adolescent fertility across countries. Nevertheless, this key finding is not focused on low-income countries. This study applies a multilevel logistic regression of country-level adolescent fertility on country-level income inequality plus individual-level income and controls to the Demographic and Health Surveys data. A negative association between income inequality and adolescent fertility was found among low-income countries, controlling for income (OR = 0.981; 95%CI: 0.963-0.999. Different measures and different subsamples of countries show the same results. Therefore, the international association between income inequality and adolescent fertility seems more complex than previously thought.

Impact of public programs on fertility and gender specific investment in human capital of children in rural India: cross sectional and time series analyses.

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Duraisamy, P; Malathy, R

1991-01-01

Cross sectional and time series analyses are conducted with 1971 and 1981 rural district level data for India in order to estimate variations in program impacts on household decisionmaking concerning fertility, child mortality, and schooling; to analyze how the variation in public program subsidies and services influences sex specific investments in schooling; and to examine the bias in cross sectional estimates by employing fixed effects methodology. The theory of household production uses the framework development by Rosenzweig and Wolpin. The utility function is expressed as a function of families' desired number of children, sex specific investment in human capital of children measured by schooling of males and females, and a composite consumption good. Budget constraints are characterized in terms of the biological supply of births or natural fertility, the number of births averted by fertility control, exogenous money income, the prices of number of children, contraceptives, child schooling, and consumption of goods. Demand functions are constructed from maximizing the utility function subject to the budget constraint. Data constitute 40% of the total districts and 50% of the rural population. The empirical specification of the linear model and variable description are provided. Other explanatory variables included are adult educational attainment; % of scheduled castes and tribes and % Muslim; and % rural population. Estimation methods are described and justification is provided for the use of ordinary least squares and fixed effects methods. The results of the cross sectional analysis reveal that own-program effects of family planning and primary health centers reduced family size in 1971 and 81. The increase in secondary school enrollment is evidenced in only 1971. There is a significant effect of family planning (FP) clinics on the demand for surviving children only in 1971. The presence of a seconary school in a village reduces the demand for children in

Oviductal extracellular vesicles (oviductosomes, OVS) are conserved in humans: murine OVS play a pivotal role in sperm capacitation and fertility.

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Bathala, Pradeepthi; Fereshteh, Zeinab; Li, Kun; Al-Dossary, Amal A; Galileo, Deni S; Martin-DeLeon, Patricia A

2018-03-01

Are extracellular vesicles (EVs) in the murine oviduct (oviductosomes, OVS) conserved in humans and do they play a role in the fertility of Pmca4-/- females? OVS and their fertility-modulating proteins are conserved in humans, arise via the apocrine pathway, and mediate a compensatory upregulation of PMCA1 (plasma membrane Ca2+-ATPase 1) in Pmca4-/- female mice during proestrus/estrus, to account for their fertility. Recently murine OVS were identified and shown during proestrus/estrus to express elevated levels of PMCA4 which they can deliver to sperm. PMCA4 is the major Ca2+ efflux pump in murine sperm and Pmca4 deletion leads to loss of sperm motility and male infertility as there is no compensatory upregulation of the remaining Ca2+ pump, PMCA1. Of the four family members of PMCAs (PMCA1-4), PMCA1 and PMCA4 are ubiquitous, and to date there have been no reports of one isoform being upregulated to compensate for another in any organ/tissue. Since Pmca4-/- females are fertile, despite the abundant expression of PMCA4 in wild-type (WT) OVS, we propose that OVS serve a role of packaging and delivering to sperm elevated levels of PMCA1 in Pmca4-/- during proestrus/estrus to compensate for PMCA4's absence. Fallopian tubes from pre-menopausal women undergoing hysterectomy were used to study EVs in the luminal fluid. Oviducts from sexually mature WT mice were sectioned after perfusion fixation to detect EVs in situ. Oviducts were recovered from WT and Pmca4-/- after hormonally induced estrus and sectioned for PMCA1 immunofluorescence (IF) (detected with confocal microscopy) and hematoxylin and eosin staining. Reproductive tissues, luminal fluids and EVs were recovered after induced estrus and after natural cycling for western blot analysis of PMCA1 and qRT-PCR of Pmca1 to compare expression levels in WT and Pmca4-/-. OVS, uterosomes, and epididymal luminal fluid were included in the comparisons. WT and Pmca4-/- OVS were analyzed for the presence of known PMCA4 partners

Evaluation of Morphometrical and Histomorphometrical Changes of Testes, Fertility Potential and Sperm Quality in Mice Treated with Aflatoxin

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abbas Ahamdi

2017-03-01

Full Text Available Introduction: Aflatoxin is the most important mycotoxin toxicity and can enter the animal or human reproductive systems and cause some problems in relation to semen quality and fertility decline. The aim of this study was to investigate the effect of aflatoxin on histological structure of the testes and sperm characteristics and cellular targets in spermatogenic compartment and blood level of testosterone and fertility potential. Methods: In this experimental study, 40 adult male mice were divided into 4 groups as the control and experimental groups. Experimental groups have received aflatoxin (100, 350, 700µg/kg by gastric intubation daily. After 45 days, the mice were sacrificed and sperm samples were collected from cauda epididyms in order to evaluate the sperm parameters and perform the in-vitro fertilization analyses. Results: Analyses of sperm parameters demonstrated that sperm motility decreased remarkably (P<0.05 in all three groups of aflatoxin in comparison with the control. Moreover, the percentage of sperms with DNA disintegrity and nuclear immaturity were significantly increased in aflatoxin groups (P<0.05. Results from IVF showed that aflatoxin have been significantly decreased the sperm fertilization potential, preimplantation embryonic development, embryonic quality and percentage of 2-cells embryos and blasocyste in comparison with the control group. Percentage of arrested embryos with high lysis and fragmantation have been increased significantly in aflatoxin-treated groups (P<0.05. Conclusion: Totally, the present results highly support the idea that aflatoxin induces testicular toxicity with adverse effect on sperm quality and fertility potential in a dose-dependent manner. 

Genetic variants determining survival and fertility in an adverse African environment

DEFF Research Database (Denmark)

Koopman, Jacob J E; Pijpe, Jeroen; Böhringer, Stefan

2016-01-01

Human survival probability and fertility decline strongly with age. These life history traits have been shaped by evolution. However, research has failed to uncover a consistent genetic determination of variation in survival and fertility. As an explanation, such genetic determinants have been...... selected in adverse environments, in which humans have lived during most of their history, but are almost exclusively studied in populations in modern affluent environments. Here, we present a large-scale candidate gene association study in a rural African population living in an adverse environment...

Human 3β-hydroxysteroid dehydrogenase deficiency seems to affect fertility but may not harbor a tumor risk

DEFF Research Database (Denmark)

Burckhardt, Marie-Anne; Udhane, Sameer S; Marti, Nesa

2015-01-01

enlarged breasts through production of estrogens in the periphery. Testis histology in late puberty revealed primarily a Sertoli-cell-only pattern and only few tubules with arrested spermatogenesis, presence of few Leydig cells in stroma, but no neoplastic changes. CONCLUSIONS: The testis with HSD3B2...... histology, fertility and malignancy risk. OBJECTIVE: To describe the molecular genetics, the steroid biochemistry, the (immuno-)histochemistry and the clinical implications of a loss-of-function HSD3B2 mutation. METHODS: Biochemical, genetic and immunohistochemical investigations on human biomaterials...

Starch derivative-based superabsorbent with integration of water-retaining and controlled-release fertilizers.

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Zhong, Kang; Lin, Zuan-Tao; Zheng, Xi-Liang; Jiang, Gang-Biao; Fang, Yu-Sheng; Mao, Xiao-Yun; Liao, Zong-Wen

2013-02-15

Phosphate rock (PHR), a traditional fertilizer, is abundant, but is hard to be utilized by plants. To improve the utilization of PHR, and to integrate water-retaining and controlled-release fertilizers, an agricultural superabsorbent polymer based on sulfonated corn starch/poly (acrylic acid) embedding phosphate rock (SCS/PAA/PHR) was prepared. PHR can be suspended and well-dispersed in SCS/PAA by sulfonated corn starch (SCS). PHR and KOH were mixed in acrylic acid solution to provide phosphorus (P) and potassium (K) nutrients, respectively. Impacts on water absorption capacity of the superabsorbent were investigated. The maximum swelling capacity in distilled water or 0.9 wt.% (weight percent) NaCl solution reached 498 g g(-1) and 65 g g(-1) (water/prepared dry superabsorbent) respectively. Moreover, release behaviours of P and K in SCS/PAA/PHR were also investigated. The results showed that SCS/PAA/PHR possessed excellent sustained-release property of plant nutrient, and the SCS/PAA could improve the P release greatly. Besides, the XPS analysis was employed to study the relationship between PHR and superabsorbent polymer. Copyright © 2012 Elsevier Ltd. All rights reserved.

In vitro fertilization and embryo culture strongly impact the placental transcriptome in the mouse model.

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Patricia Fauque

Full Text Available BACKGROUND: Assisted Reproductive Technologies (ART are increasingly used in humans; however, their impact is now questioned. At blastocyst stage, the trophectoderm is directly in contact with an artificial medium environment, which can impact placental development. This study was designed to carry out an in-depth analysis of the placental transcriptome after ART in mice. METHODOLOGY/PRINCIPAL FINDINGS: Blastocysts were transferred either (1 after in vivo fertilization and development (control group or (2 after in vitro fertilization and embryo culture. Placentas were then analyzed at E10.5. Six percent of transcripts were altered at the two-fold threshold in placentas of manipulated embryos, 2/3 of transcripts being down-regulated. Strikingly, the X-chromosome harbors 11% of altered genes, 2/3 being induced. Imprinted genes were modified similarly to the X. Promoter composition analysis indicates that FOXA transcription factors may be involved in the transcriptional deregulations. CONCLUSIONS: For the first time, our study shows that in vitro fertilization associated with embryo culture strongly modify the placental expression profile, long after embryo manipulations, meaning that the stress of artificial environment is memorized after implantation. Expression of X and imprinted genes is also greatly modulated probably to adapt to adverse conditions. Our results highlight the importance of studying human placentas from ART.

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

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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

Inhibiting sperm pyruvate dehydrogenase complex and its E3 subunit, dihydrolipoamide dehydrogenase affects fertilization in Syrian hamsters.

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Archana B Siva

Full Text Available BACKGROUND/AIMS: The importance of sperm capacitation for mammalian fertilization has been confirmed in the present study via sperm metabolism. Involvement of the metabolic enzymes pyruvate dehydrogenase complex (PDHc and its E3 subunit, dihydrolipoamide dehydrogenase (DLD in hamster in vitro fertilization (IVF via in vitro sperm capacitation is being proposed through regulation of sperm intracellular lactate, pH and calcium. METHODOLOGY AND PRINCIPAL FINDINGS: Capacitated hamster spermatozoa were allowed to fertilize hamster oocytes in vitro which were then assessed for fertilization, microscopically. PDHc/DLD was inhibited by the use of the specific DLD-inhibitor, MICA (5-methoxyindole-2-carboxylic acid. Oocytes fertilized with MICA-treated (MT [and thus PDHc/DLD-inhibited] spermatozoa showed defective fertilization where 2nd polar body release and pronuclei formation were not observed. Defective fertilization was attributable to capacitation failure owing to high lactate and low intracellular pH and calcium in MT-spermatozoa during capacitation. Moreover, this defect could be overcome by alkalinizing spermatozoa, before fertilization. Increasing intracellular calcium in spermatozoa pre-IVF and in defectively-fertilized oocytes, post-fertilization rescued the arrest seen, suggesting the role of intracellular calcium from either of the gametes in fertilization. Parallel experiments carried out with control spermatozoa capacitated in medium with low extracellular pH or high lactate substantiated the necessity of optimal sperm intracellular lactate levels, intracellular pH and calcium during sperm capacitation, for proper fertilization. CONCLUSIONS: This study confirms the importance of pyruvate/lactate metabolism in capacitating spermatozoa for successful fertilization, besides revealing for the first time the importance of sperm PDHc/ DLD in fertilization, via the modulation of sperm intracellular lactate, pH and calcium during capacitation. In

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

Intermittent control: a computational theory of human control.

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Gawthrop, Peter; Loram, Ian; Lakie, Martin; Gollee, Henrik

2011-02-01

The paradigm of continuous control using internal models has advanced understanding of human motor control. However, this paradigm ignores some aspects of human control, including intermittent feedback, serial ballistic control, triggered responses and refractory periods. It is shown that event-driven intermittent control provides a framework to explain the behaviour of the human operator under a wider range of conditions than continuous control. Continuous control is included as a special case, but sampling, system matched hold, an intermittent predictor and an event trigger allow serial open-loop trajectories using intermittent feedback. The implementation here may be described as "continuous observation, intermittent action". Beyond explaining unimodal regulation distributions in common with continuous control, these features naturally explain refractoriness and bimodal stabilisation distributions observed in double stimulus tracking experiments and quiet standing, respectively. Moreover, given that human control systems contain significant time delays, a biological-cybernetic rationale favours intermittent over continuous control: intermittent predictive control is computationally less demanding than continuous predictive control. A standard continuous-time predictive control model of the human operator is used as the underlying design method for an event-driven intermittent controller. It is shown that when event thresholds are small and sampling is regular, the intermittent controller can masquerade as the underlying continuous-time controller and thus, under these conditions, the continuous-time and intermittent controller cannot be distinguished. This explains why the intermittent control hypothesis is consistent with the continuous control hypothesis for certain experimental conditions.

Neuroendocrine control by kisspeptins: role in metabolic regulation of fertility.

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Navarro, Victor M; Tena-Sempere, Manuel

2011-09-13

The neurohormonal control of reproduction involves a hierarchical network of central and peripheral signals in the hypothalamic-pituitary-gonadal (HPG) axis. Development and function of this neuroendocrine system is the result of a lifelong delicate balance between endogenous regulators and environmental cues, including nutritional and metabolic factors. Kisspeptins are the peptide products of KISS1, which operate via the G-protein-coupled receptor GPR54 (also known as Kiss1R). These peptides have emerged as essential upstream regulators of neurons secreting gonadotropin-releasing hormone (GnRH), the major hypothalamic node for the stimulatory control of the HPG axis. They are potent elicitors of gonadotropin secretion in various species and physiological settings. Moreover, Kiss1 neurons in the hypothalamus participate in crucial features of reproductive maturation and function, such as brain-level sex differentiation, puberty onset and the neuroendocrine regulation of gonadotropin secretion and ovulation. Cotransmitters of Kiss1 neurons, such as neurokinin B, with roles in controlling the HPG axis have been identified by genetic, neuroanatomical and physiological studies. In addition, a putative role has been proposed for Kiss1 neurons in transmitting metabolic information to GnRH neurons, although the precise mechanisms are as yet unclear. In this Review, we present the major reproductive features of kisspeptins, especially their interplay with neurokinin B and potential roles in the metabolic control of puberty and fertility, and suggest new avenues for research.

Effects of fertilizers used in agricultural fields on algal blooms

DEFF Research Database (Denmark)

Chakraborty, Subhendu; Tiwari, P. K.; Sasmal, S. K.

2017-01-01

of factors and from observation it is difficult to identify the most important one. In the present paper, using a mathematical model we compare the effects of three human induced factors (fertilizer input in agricultural field, eutrophication due to other sources than fertilizers, and overfishing......) on the bloom dynamics and DO level. By applying a sophisticated sensitivity analysis technique, we found that the increasing use of fertilizers in agricultural field causes more rapid algal growth and decreases DO level much faster than eutrophication from other sources and overfishing. We also look...... at the mechanisms how fertilizer input rate affects the algal bloom dynamics and DO level. The model can be helpful for the policy makers in determining the influential factors responsible for the bloom formation....

Effects of Dietary Vitamin E on Fertility Functions in Poultry Species

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Deivendran Rengaraj

2015-04-01

Full Text Available Vitamin E is found in high quantities in vegetable oils. Although vitamin E has multiple functions in humans and animals, its key function is protecting cells from oxidative damage. Since its discovery, several studies have demonstrated that vitamin E deficiency causes impaired fertility in humans and lab animals. However, the effects of vitamin E deficiency or of its supplementation on the fertility of farm animals, particularly on poultry, are less well studied. Therefore, a comprehensive review of the effects of dietary vitamin E on the fertility of poultry species is needed in order to understand the beneficial role of vitamin E in the maintenance of sperm and egg qualities. Based on the observations reviewed here, we found that a moderate amount of vitamin E in poultry diet significantly protects semen/sperm qualities in male birds and egg qualities in female birds via decreasing the lipid peroxidation in semen/sperms and eggs. This review provides an overall understanding of the effects of dietary vitamin E on fertility functions in poultry species.

The Impact of Subjective Work Control, Job Strain and Work-Family Conflict on Fertility Intentions : a European Comparison

NARCIS (Netherlands)

Begall, Katia; Mills, Melinda

The link between employment and fertility is often only examined by focussing on women's labour market status or the impact of part- versus full-time employment. This study introduces a new explanation by extending research to examine how women's subjective perceptions of control or autonomy over

Evaluation of plasma membrane calcium/calmodulin-dependent ATPase isoform 4 as a potential target for fertility control.

Science.gov (United States)

Cartwright, Elizabeth J; Neyses, Ludwig

2010-01-01

The array of contraceptives currently available is clearly inadequate and does not meet consumer demands since it is estimated that up to a quarter of all pregnancies worldwide are unintended. There is, therefore, an overwhelming global need to develop new effective, safe, ideally non-hormonal contraceptives for both male and female use. The contraceptive field, unlike other areas such as cancer, has a dearth of new targets. We have addressed this issue and propose that isoform 4 of the plasma membrane calcium ATPase is a potentially exciting novel target for fertility control. The plasma membrane calcium ATPase is a ubiquitously expressed calcium pump whose primary function in the majority of cells is to extrude calcium to the extracellular milieu. Two isoforms of this gene family, PMCA1 and PMCA4, are expressed in spermatozoa, with PMCA4 being the predominant isoform. Although this gene is ubiquitously expressed, its function is highly tissue-specific. Genetic deletion of PMCA4, in PMCA4 knockout mice, led to 100% infertility specifically in the male mutant mice due to a selective defect in sperm motility. It is important to note that the gene deletion did not affect normal mating characteristics in these mice. This phenotype was mimicked in wild-type sperm treated with the non-specific PMCA inhibitor 5-(and 6-) carboxyeosin diacetate succinimidyl ester; a proof-of-principle that inhibition of PMCA4 has potential importance in the control of fertility. This review outlines the potential for PMCA4 to be a novel target for fertility control by acting to inhibit sperm motility. It will outline the characteristics that make this target drugable and will describe methodologies to identify and validate novel inhibitors of this target.

Census-linked Study on Ethnic Fertility Differentials in Lithuania

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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.

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.

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.

Advanced reproductive age and fertility.

Science.gov (United States)

Liu, Kimberly; Case, Allison

2011-11-01

To improve awareness of the natural age-related decline in female and male fertility with respect to natural fertility and assisted reproductive technologies (ART) and provide recommendations for their management, and to review investigations in the assessment of ovarian aging. This guideline reviews options for the assessment of ovarian reserve and fertility treatments using ART with women of advanced reproductive age presenting with infertility. The outcomes measured are the predictive value of ovarian reserve testing and pregnancy rates with natural and assisted fertility. Published literature was retrieved through searches of PubMed or Medline, CINAHL, and The Cochrane Library in June 2010, using appropriate key words (ovarian aging, ovarian reserve, advanced maternal age, advanced paternal age, ART). Results were restricted to systematic reviews, randomized controlled trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated into the guideline to December 2010. The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice were ranked according to the method described in that report (Table). Primary and specialist health care providers and women will be better informed about ovarian aging and the age-related decline in natural fertility and about options for assisted reproductive technology. 1. Women in their 20s and 30s should be counselled about the age-related risk of infertility when other reproductive health issues, such as sexual health or contraception, are addressed as part of their primary well-woman care. Reproductive-age women should be aware that natural fertility and assisted reproductive technology success (except with egg donation) is significantly lower for women in their late 30s and 40s. (II-2A) 2. Because of the decline in fertility and the

Will human populations be limited by food?

Science.gov (United States)

Warren, S. G.

2016-12-01

Historical examples of demographic change, in China, Italy, Nigeria, Utah, the Philippines, and elsewhere, together with simple mathematics and biological principles, show that stabilizing world population before it is limited by food supply will be more difficult than is generally appreciated. United Nations population projections are based on a logical fallacy in that they assume, in spite of the absence of necessary negative feedbacks, that all nations will converge rapidly to replacement-level fertility and thereafter remain at that level. The benign projections that have resulted from this assumption may have hindered efforts to make availability of birth-control a priority in development-aid. Education of women and provision of contraceptives have caused dramatic reductions in fertility, but many groups, including some that are well-educated, maintain high fertility. Small groups with persistent high fertility can grow to supplant low-fertility groups, resulting in continued growth of the total population. The global average fertility rate could rise even if each country's fertility rate is falling. In some low-fertility European countries where deaths exceed births, the population continues to grow because of immigration. Producing more than two offspring is normal for all animal species with stable populations, because their populations are limited by resources or predation rather than birth control. It may therefore be appropriate to view the growth of human population as the result not of excess fertility but rather of excess food. Even if the fertility rate is maintained far in excess of 2, the population cannot grow if food is limiting. Without the agricultural advances of the 20thcentury, world population could not have grown as it did from 1.7 billion in 1900 to 6 billion in 2000. The food supply may be enhanced in the future by genetic engineering and other innovations, but it may be limited by water shortage, climate change, pollution, and energy

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.

NCHS - Births and General Fertility Rates: United States

Data.gov (United States)

U.S. Department of Health & Human Services — This dataset includes crude birth rates and general fertility rates in the United States since 1909. The number of states in the reporting area differ historically....

The impact of subjective work control, job strain and work-family conflict on fertility intentions: a European comparison

NARCIS (Netherlands)

Begall, K.; Mills, M.

2011-01-01

The link between employment and fertility is often only examined by focussing on women’s labour market status or the impact of part- versus full-time employment. This study introduces a new explanation by extending research to examine how women’s subjective perceptions of control or autonomy over

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...

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

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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.

Effects of Chemical and Organic Fertilizers on Growth, Yield and Yield Component of Tomato (Lycopersicon sculentum L.

Directory of Open Access Journals (Sweden)

R Mirzaei Talarposhti

2017-03-01

Full Text Available Introduction Although using animal manures and crop residues as a traditional method for increasing soil fertility and crop yield has a long history but Conventional agricultural systems rely on the use of chemical fertilizer due to its immediate availability of nutrients. In many of modern agricultural systems using chemical fertilizers as a fast and easiest way to reduce nutrient deficiency and increasing soil fertility is considered. Intensive and continuous use of chemical fertilizers leads to decreasing the stability and sustainability of agricultural systems and also poses major threat to environment and human health. Organic fertilizers have positive effects on physiochemical and biological attributes of soil and could be classified in three different groups (i.e. Animal manures, green manure and composts.Using animal manure not only increase soil fertility but also could result in increasing infiltration, aeration and water holding capacity of soil. The main role of these fertilizers is related to physical change in soil. Different types of composts such as municipal waste compost and vermicompost also have similar positive effects, but usually the farmers observe the main effect of these organic fertilizers in long term. In order to investigate the effects of different types of organic fertilizers on growth indexes, yield and yield component of tomato (Lycopersicon sculentum L. current experiment was conducted. Materials and Methods The experiment was conducted based on randomized complete block design (RCBD with three replications and six treatments in the research station of Shahid Beheshti University. The experimental treatments were: Control or no fertilizer (NF, chemical fertilizer (CF, cow manure (CM, poultry manure (PM, vermicompost (VC and municipal waste compost (MC. Considering nitrogen concentration in all of the treatments different amounts of these fertilizers were used based on nitrogen recommendation for the field, so in

India's Fertilizer Industry: Productivity and Energy Efficiency

Energy Technology Data Exchange (ETDEWEB)

Schumacher, K.; Sathaye, J.

1999-07-01

Historical estimates of productivity growth in India's fertilizer sector vary from indicating an improvement to a decline in the sector's productivity. The variance may be traced to the time period of study, source of data for analysis, and type of indices and econometric specifications used for reporting productivity growth. Our analysis shows that in the twenty year period, 1973 to 1993, productivity in the fertilizer sector increased by 2.3% per annum. An econometric analysis reveals that technical progress in India's fertilizer sector has been biased towards the use of energy, while it has been capital and labor saving. The increase in productivity took place during the era of total control when a retention price system and distribution control was in effect. With liberalization of the fertilizer sector and reduction of subsidies productivity declined substantially since the early 1990s. Industrial policies and fiscal incentives still play a major role in the Indian fertilizer sect or. As substantial energy savings and carbon reduction potential exists, energy policies can help overcome barriers to the adoption of these measures in giving proper incentives and correcting distorted prices.

The secretory products of Trichomonas vaginalis decrease fertilizing capacity of mice sperm in vitro

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Jaesook Roh

2015-04-01

Full Text Available Trichomonas vaginalis infection is one of the most prevalent sexually transmitted infections in humans and is now recognized as an important cause of infertility in men. There is little information about the effect of extracellular polymeric substances (EPS from T. vaginalis on sperm, but previous reports do not provide a conclusive description of the functional integrity of the sperm. To investigate the impact of EPS on the fertilizing capacity of sperm, we assessed sperm motility, acrosomal status, hypo-osmotic swelling, and in vitrofertilization rate after incubating the sperm with EPS in vitrousing mice. The incubation of sperm with EPS significantly decreased sperm motility, viability, and functional integrity in a concentration and time-dependent manner. These effects on sperm quality also resulted in a decreased fertilization rate in vitro. This is the first report that demonstrates the direct negative impact of the EPS of T. vaginalis on the fertilization rate of sperm in vitro. However, further study should be performed using human sperm to determine if EPS has similar negative impact on human sperm fertilizing capacity in vitro.

The role of management in an in vitro fertilization practice.

Science.gov (United States)

Masler, Steve; Strickland, Robert R

2013-05-01

An in vitro fertilization (IVF) practice is an enterprise. Like any enterprise, it has management that plays a major role, forming the structure, framework, and components that make the practice viable. Management of an IVF practice consists of two key teams: the fertility team and the management team. Management activities of the teams fall into eight core areas: business operations, financial, human resources, information technology, organizational governance, risk management, patient care systems, and quality management. Shady Grove Fertility Centers and Huntington Reproductive Center are two examples of professionally managed large fertility practices, one managed mostly centrally and the other largely managed in a decentralized way. Management is what takes a physician's IVF practice and converts it to a professional enterprise. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Theoretical explanations of the rapid fertility decline in China.

Science.gov (United States)

Wu, C

1986-07-01

A 1982 population census recorded China's fertility rate in 1982 at 2.6; recent statistics of China's State Statistics Bureau record China's 1984 birth rate at 17 per 1000 and the total fertility rate at 1.94. Wu Cangping asserts that this world-recognized rapid fertility decline is not due to any compulsory governmental restrictions on fertility, but to the people's willingness to control fertility voluntarily. He cites a number of socioeconomic factors contributing to this voluntary decline in China's birth rates: 1) change of family function; 2) decline of mortality, particularly infant mortality; 3) improvement in the educational level; 4) improvement in women's social status, especially increased employment; 5) better social security services for the elderly; 6) the preference for modern ways of production and life; and 7) the availability of information on population and birth control. He attributes these factors to the socialist system with its nationalized production, centralized planning of the national economy, and the even distribution system which prevents polarization of earning. In addition, reforms have been carried out in all aspects of social life and recent advances have been made in science and technology. All of these factors have resulted in a more rapid fertility transition in China as compared to that of developed countries in their past and that of developing countries at present.

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.

The control of male fertility by spermatid-specific factors: searching for contraceptive targets from spermatozoon's head to tail

Science.gov (United States)

Chen, Su-Ren; Batool, Aalia; Wang, Yu-Qian; Hao, Xiao-Xia; Chang, Chawn-Shang; Cheng, C Yan; Liu, Yi-Xun

2016-01-01

Male infertility due to abnormal spermatozoa has been reported in both animals and humans, but its pathogenic causes, including genetic abnormalities, remain largely unknown. On the other hand, contraceptive options for men are limited, and a specific, reversible and safe method of male contraception has been a long-standing quest in medicine. Some progress has recently been made in exploring the effects of spermatid-specifical genetic factors in controlling male fertility. A comprehensive search of PubMed for articles and reviews published in English before July 2016 was carried out using the search terms ‘spermiogenesis failure', ‘globozoospermia', ‘spermatid-specific', ‘acrosome', ‘infertile', ‘manchette', ‘sperm connecting piece', ‘sperm annulus', ‘sperm ADAMs', ‘flagellar abnormalities', ‘sperm motility loss', ‘sperm ion exchanger' and ‘contraceptive targets'. Importantly, we have opted to focus on articles regarding spermatid-specific factors. Genetic studies to define the structure and physiology of sperm have shown that spermatozoa appear to be one of the most promising contraceptive targets. Here we summarize how these spermatid-specific factors regulate spermiogenesis and categorize them according to their localization and function from spermatid head to tail (e.g., acrosome, manchette, head-tail conjunction, annulus, principal piece of tail). In addition, we emphatically introduce small-molecule contraceptives, such as BRDT and PPP3CC/PPP3R2, which are currently being developed to target spermatogenic-specific proteins. We suggest that blocking the differentiation of haploid germ cells, which rarely affects early spermatogenic cell types and the testicular microenvironment, is a better choice than spermatogenic-specific proteins. The studies described here provide valuable information regarding the genetic and molecular defects causing male mouse infertility to improve our understanding of the importance of spermatid

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.

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.

Age at First Birth, Fertility, and Contraception in Tanzania

OpenAIRE

Ngalinda, Innocent

1998-01-01

The first visible outcome of the fertility process is the birth of the first child. The first birth marks a woman's transition into motherhood. It plays a significant role in the future life of each individual woman and has a direct relationship with fertility. The age at which child bearing begins influences the number of children a woman bears throughout her reproductive period in the absence of any active fertility control. For countries in sub-Saharan Africa, where contraceptive use is re...

Do natural methods for fertility regulation increase the risks of genetic errors?

Science.gov (United States)

Serra, A

1981-09-01

Genetic errors of many kinds are connected with the reproductive processes and are favored by a nunber of largely uncontrollable, endogenous, and/or exogenous factors. For a long time human beings have taken into their own hands the control of this process. The regulation of fertility is clearly a forceful request to any family, to any community, were it only to lower the level of the consequences of genetic errors. In connection with this request, and in the context of the Congress for the Family of Africa and Europe (Catholic University, January 1981), 1 question must still be raised and possibly answered. The question is: do or can the so called "natural methods" for the regulation of fertility increase the risks of genetic errors with their generally dramatic effects on families and on communities. It is important to try to give as far as possible a scientifically based answer to this question. Fr. Haring, a moral theologian, citing scientific evidence finds it shocking that the rhythm method, so strongly and recently endorsed again by Church authorities, should be classified among the means of "birth control" by way of spontaneous abortion or at least by spontaneous loss of a large number of zygotes which, due to the concrete application of the rhythm method, lack of necessary vitality for survival. He goes on to state that the scientific research provides overwhelming evidence that the rhythm method in its traditional form is responsible for a disproportionate waste of zygotes and a disproportionate frequency of spontaneous abortions and a defective childern. Professor Hilgers, a reproductive physiologist, takes on opposite view, maintaining that the hypotheses are arbitrary and the alarm false. The strongest evidence upon which Fr. Haring bases his moral principles about the use of the natural methods of fertility regulation is a paper by Guerrero and Rojos (1975). These authors examined, retrospectively, the success of 965 pregnancies which occurred in

Mercury in rice (Oryza sativa L.) and rice-paddy soils under long-term fertilizer and organic amendment.

Science.gov (United States)

Tang, Zhenya; Fan, Fangling; Wang, Xinyue; Shi, Xiaojun; Deng, Shiping; Wang, Dingyong

2018-04-15

High levels of mercury (Hg), especially methylmercury (MeHg), in rice is of concern due to its potential of entering food chain and the high toxicity to human. The level and form of Hg in rice could be influenced by fertilizers and other soil amendments. Studies were conducted to evaluate the effect of 24 years application of chemical fertilizers and organic amendments on total Hg (THg) and MeHg and their translocation in soil, plants, and rice grain. All treatments led to significantly higher concentrations of MeHg in grain than those from the untreated control. Of nine treatments tested, chemical fertilizers combining with returning rice straw (NPK1+S) led to highest MeHg concentration in grain and soil; while the nitrogen and potassium (NK) treatment led to significantly higher THg in grain. Concentrations of soil MeHg were significantly correlated with THg in soil (r = 0.59 *** ) and MeHg in grain (r = 0.48 *** ). Calcium superphosphate negatively affected plant bioavailability of soil Hg. MeHg concentration in rice was heavily influenced by soil Hg levels. Phosphorus fertilizer was a main source contributing to soil THg, while returning rice straw to the field contributed significantly to MeHg in soil and rice grain. As a result, caution should be exercised in soil treatment or when utilizing Hg-contaminated soils to produce rice for human consumption. Strategic management of rice straw and phosphorus fertilizer could be effective strategies of lowering soil Hg, which would ultimately lower MeHg in rice and the risk of Hg entering food chain. Copyright © 2017 Elsevier Inc. All rights reserved.

Impact of fertilizer plant effluent on water quality

International Nuclear Information System (INIS)

Obire, O.; Ogan, A.; Okigbo, R. N.

2008-01-01

The impact of National Fertilizer Company of Nigeria out fall effluent on the physico chemistry and bacteriology of Okrika creek was investigated during the sampling period from May to December, 1998. The National Fertilizer Company of Nigeria out fall effluent, the Okrika creek water and the lkpukulubie creek (control) water samples were collected. The physico-chemical parameters analyzed for all the samples included temperature, p H, total chloride, total dissolved solids, dissolved oxygen, conductivity, free ammonia, total phosphate, urea, zinc and iron, while the bacteriological determinations were total culturable aerobic heterotrophic bacteria count and identification of representative isolates. The Okrika creek recorded higher concentrations for all the physicochemical parameters and bacteria load than the control creek. The higher values of p H, Free NH 3 , urea, TDS and the conductivity of the National Fertilizer Company of Nigeria out fall effluent above the FEPA standards reflect the poor effluent quality generated by National Fertilizer Company of Nigeria. The bacteria species isolated from the samples include Aerococcus viridans, Alcaligenes faecalis, Bacillus cereus, Citrobacter freundii, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens and Staphylococcus aureus. In general, the investigation revealed that there was an extremely adverse impact on the physico-chemical and bacteriological water quality characteristics of the Okrika creek as a result of the discharge of poor quality effluent from National Fertilizer Company of Nigeria operations

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.

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

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.

Decrease in male mouse fertility by hydrogen sulfide and/or ammonia can Be inheritable.

Science.gov (United States)

Zhang, Weidong; Zhao, Yong; Zhang, Pengfei; Hao, Yanan; Yu, Shuai; Min, Lingjiang; Li, Lan; Ma, Dongxue; Chen, Liang; Yi, Bao; Tang, Xiangfang; Meng, Qingshi; Liu, Lei; Wang, Shukun; Shen, Wei; Zhang, Hongfu

2018-03-01

Numerous epidemiological studies suggest that air pollutants cause a decline in the quality of human spermatozoa and thus a reduction in fertility. However, the exact cause of infertility remains unknown. Air pollution gases, such as NH 3 and H 2 S are either free or bound to airborne particular materials (PM) and are abundant and reactive. The aim of this current investigation was to explore the impacts of NH 3 and/or H 2 S on male fertility and the underlying mechanisms. Male mouse exposed to H 2 S and/or NH 3 and after two generations were used to evaluate the impacts on fertility. The fertility, and spermatozoa quality parameters and proteins involved in spermatogenesis were investigated. Our current investigation demonstrates: i) H 2 S and/or NH 3 decrease male fertility by 20-30%, reduce the spermatozoa concentration about 20-40%, decrease 10-20%, increase around 30%; ii) the reduction in male fertility by H 2 S and/or NH 3 can be inheritable; iii) H 2 S and/or NH 3 can diminish male fertility through the disruption of spermatogenesis without affecting other body parameters such as body weight and organ index. One component of air pollutants, for example NH 3 , does not have a severe impact; however, two or more pollutants such as H 2 S and NH 3 combined can cause serious health problems, especially with regard to male fertility. We suggest that greater attention should be paid to these air pollutants to improve human health and fertility. Copyright © 2017 Elsevier Ltd. All rights reserved.

External costs of cadmium emissions to soil: a drawback of phosphorus fertilizers

DEFF Research Database (Denmark)

Pizzol, Massimo; C.R. Smart, James; Thomsen, Marianne

2014-01-01

are exposed to cadmium through their diet causing potential adverse health impacts. Future scenarios for cadmium emissions to soil via agricultural applications of inorganic and organic fertilizers in Denmark were defined. A simplified fate and speciation model allowed the increase in soil cadmium......Abstract: In this study the Impact-Pathway Approach methodology was applied for monetary valuation of health impacts due to cadmium emitted to soil as a micro-pollutant present in phosphorus fertilizers. Due to the high persistency of cadmium in soil, and high soil-to-plant transfer rates, humans...... ammonium phosphate) and mineral fertilizer produced the lowest external health costs, followed by the fertilizer products wastewater sludge and pig manure. The external cost estimates produced in this study could be used to design economic policy instruments to encourage use of cleaner fertilizer products....

Measurement of natural radioactivity in chemical fertilizer and agricultural soil: evidence of high alpha activity.

Science.gov (United States)

Ghosh, Dipak; Deb, Argha; Bera, Sukumar; Sengupta, Rosalima; Patra, Kanchan Kumar

2008-02-01

People are exposed to ionizing radiation from the radionuclides that are present in different types of natural sources, of which phosphate fertilizer is one of the most important sources. Radionuclides in phosphate fertilizer belonging to 232Th and 238U series as well as radioisotope of potassium (40K) are the major contributors of outdoor terrestrial natural radiation. The study of alpha activity in fertilizers, which is the first ever in West Bengal, has been performed in order to determine the effect of the use of phosphate fertilizers on human health. The data have been compared with the alpha activity of different types of chemical fertilizers. The measurement of alpha activity in surface soil samples collected from the cultivated land was also performed. The sampling sites were randomly selected in the cultivated land in the Midnapore district, which is the largest district in West Bengal. The phosphate fertilizer is widely used for large agricultural production, mainly potatoes. The alpha activities have been measured using solid-state nuclear track detectors (SSNTD), a very sensitive detector for alpha particles. The results show that alpha activity of those fertilizer and soil samples varies from 141 Bq/kg to 2,589 Bq/kg and from 109 Bq/kg to 660 Bq/kg, respectively. These results were used to estimate environmental radiation exposure on human health contributed by the direct application of fertilizers.

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.

New Reproductive Assemblages: Understanding, Managing and ‘Using’ Human In Vitro Fertilization (IVF)

OpenAIRE

Just, E.M.

2009-01-01

This dissertation is a contribution to the ongoing discussion about the body and in vitro fertilization (IVF), also known as assisted reproduction or technologically enhanced reproduction. With help of empirical research on Dutch and Polish IVF-couples, Edyta Just puts into question the meaning of IVF and discusses the best way of managing the phenomenon and to use it to transform existing ideologies, norms, convictions en discussions on matters such as reproduction, (in)fertility, female/mal...

Embryological outcomes in cycles with human oocytes containing large tubular smooth endoplasmic reticulum clusters after conventional in vitro fertilization.

Science.gov (United States)

Itoi, Fumiaki; Asano, Yukiko; Shimizu, Masashi; Honnma, Hiroyuki; Murata, Yasutaka

2016-01-01

There have been no studies analyzing the effect of large aggregates of tubular smooth endoplasmic reticulum (aSERT) after conventional in vitro fertilization (cIVF). The aim of this study was to investigate whether aSERT can be identified after cIVF and the association between the embryological outcomes of oocytes in cycles with aSERT. This is a retrospective study examining embryological data from cIVF cycles showing the presence of aSERT in oocytes 5-6 h after cIVF. To evaluate embryo quality, cIVF cycles with at least one aSERT-metaphase II (MII) oocyte observed (cycles with aSERT) were compared to cycles with normal-MII oocytes (control cycles). Among the 4098 MII oocytes observed in 579 cycles, aSERT was detected in 100 MII oocytes in 51 cycles (8.8%). The fertilization rate, the rate of embryo development on day 3 and day 5-6 did not significantly differ between cycles with aSERT and control group. However, aSERT-MII oocytes had lower rates for both blastocysts and good quality blastocysts (p cycles with aSERT.

Prdm9 incompatibility controls oligospermia and delayed fertility but no selfish transmission in mouse intersubspecific hybrids.

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Flachs, Petr; Bhattacharyya, Tanmoy; Mihola, Ondřej; Piálek, Jaroslav; Forejt, Jiří; Trachtulec, Zdenek

2014-01-01

PR-domain 9 (Prdm9) is the first hybrid sterility gene identified in mammals. The incompatibility between Prdm9 from Mus musculus domesticus (Mmd; the B6 strain) and the Hstx2 region of chromosome (Chr) X from M. m. musculus (Mmm; the PWD strain) participates in the complete meiotic arrest of mouse intersubspecific (PWD×B6)F1 hybrid males. Other studies suggest that also semisterile intersubspecific hybrids are relevant for mouse speciation, but the genes responsible remain unknown. To investigate the causes of this semisterility, we analyzed the role of Prdm9 and Chr X in hybrids resulting from the crosses of PWK, another Mmm-derived inbred strain. We demonstrate that Prdm9 and Chr X control the partial meiotic arrest and reduced sperm count in (PWK×B6)F1 males. Asynapsis of heterosubspecific chromosomes and semisterility were partially suppressed by removal of the B6 allele of Prdm9. Polymorphisms between PWK and PWD on Chr X but not in the Prdm9 region were responsible for the modification of the outcome of Prdm9-Chr X F1 hybrid incompatibility. Furthermore, (PWK×B6)F1 hybrid males displayed delayed fertility dependent on the Prdm9 incompatibility. While the Drosophila hybrid sterility gene Overdrive causes both delayed fertility and increased transmission of its own chromosome to the offspring, the segregation of Chr X and the Prdm9 region from the mouse (PWK×B6)F1 males was normal. Our results indicate extended functional consequences of Prdm9-Chr X intersubspecific incompatibility on the fertility of hybrids and should influence the design of fertility analyses in hybrid zones and of laboratory crosses between Mmm and Mmd strains.

Prdm9 incompatibility controls oligospermia and delayed fertility but no selfish transmission in mouse intersubspecific hybrids.

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Petr Flachs

Full Text Available PR-domain 9 (Prdm9 is the first hybrid sterility gene identified in mammals. The incompatibility between Prdm9 from Mus musculus domesticus (Mmd; the B6 strain and the Hstx2 region of chromosome (Chr X from M. m. musculus (Mmm; the PWD strain participates in the complete meiotic arrest of mouse intersubspecific (PWD×B6F1 hybrid males. Other studies suggest that also semisterile intersubspecific hybrids are relevant for mouse speciation, but the genes responsible remain unknown. To investigate the causes of this semisterility, we analyzed the role of Prdm9 and Chr X in hybrids resulting from the crosses of PWK, another Mmm-derived inbred strain. We demonstrate that Prdm9 and Chr X control the partial meiotic arrest and reduced sperm count in (PWK×B6F1 males. Asynapsis of heterosubspecific chromosomes and semisterility were partially suppressed by removal of the B6 allele of Prdm9. Polymorphisms between PWK and PWD on Chr X but not in the Prdm9 region were responsible for the modification of the outcome of Prdm9-Chr X F1 hybrid incompatibility. Furthermore, (PWK×B6F1 hybrid males displayed delayed fertility dependent on the Prdm9 incompatibility. While the Drosophila hybrid sterility gene Overdrive causes both delayed fertility and increased transmission of its own chromosome to the offspring, the segregation of Chr X and the Prdm9 region from the mouse (PWK×B6F1 males was normal. Our results indicate extended functional consequences of Prdm9-Chr X intersubspecific incompatibility on the fertility of hybrids and should influence the design of fertility analyses in hybrid zones and of laboratory crosses between Mmm and Mmd strains.

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...

Does immunity regulate ejaculate quality and fertility in humans?

OpenAIRE

Philip A. Skau; Ivar Folstad

2005-01-01

The production of high-quality ejaculates may represent significant costs during male reproduction. Spermatozoa are perceived as nonself by the immune system and are exposed to immunological attacks in the male reproductive tract. Autoimmunity to spermatozoa results in the production of antisperm antibodies that reduce sperm quality and hence fertility. Thus, males are dependent on the testis being an immunoprivileged site to reduce immunological reactions against their own sperm, and immunop...

Effect of different methods of soil fertility increasing via application of organic, chemical and biological fertilizers on grain yield and quality of canola (Brassica napus L.

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K. Mohammadi

2016-05-01

Full Text Available Different resource of fertilizers had an effect on grain yield, oil and grain quality. Information regarding the effect of simultaneous application of organic, chemical and biological fertilizers on canola (Brassica napus L. traits is not available. In order to study the effect of different systems of soil fertility on grain yield and quality of canola (Talayeh cultivar, an experiment was conducted at experimental farm of Agricultural Research Center of Sanandaj, Iran, during two growing seasons of 2007-2008 and 2008-2009. The experimental units were arranged as split plots based on randomized complete blocks design with three replications. Main plots consisted of five methods for obtaining the basal fertilizers requirement including (N1: farm yard manure; (N2: compost; (N3: chemical fertilizers; (N4: farm yard manure + compost and (N5: farm yard manure + compost + chemical fertilizers; and control (N6. Sub plots consisted four levels of biofertilizers were (B1: Bacillus lentus and Pseudomonas putida; (B2: Trichoderma harzianum; (B3: Bacillus lentus and Pseudomonas putida and Trichoderma harzianum; and (B4: control, (without biofertilizers. Results showed that basal fertilizers and biofertilizers have a significant effect on grain yield. The highest grain yield was obtained from N5 treatment in which organic and chemical fertilizers were applied simultaneously applied. Basal fertilizers, biofertilizers have a significant effect on leaf chlorophyll. The highest nitrogen content (42.85 mg.g-1 and least amount of (N/S were obtained from N5 treatment. The highest oil percent was obtained from N1 and N2 treatments and highest oil yield was obtained from N5 treatment. Finally, application of organic manure and biofertilizers with chemical fertilizer led to an increase in yield and quality of canola grain.

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

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.

Productivity of irrigated beans due to sources of stabilized nitrogen fertilizer and controlled release

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Tatiely Gomes Bernardes

2015-12-01

Full Text Available ABSTRACT New nitrogen fertilizers are available in the market actually, however, does not have results on the efficiency of the Cerrado conditions. With that objective of this study was to evaluate the effect of urea including stabilized and controlled release urea on yield of irrigated common beans (Phaseolus vulgaris L in no-tillage system. The experiment was conducted in the winter crop, at Embrapa Arroz e Feijão, in Santo Antônio de Goiás, State of Goiás, Brazil. The experimental design was randomized blocks, with five replicates. Treatments consisted of five N sources (urea, urea + NBPT, urea + polymer, ammonium sulphate, and ammonium nitrate and a control (without N being applied 20 kg ha-1 of N at sowing and 80 kg ha-1 onf N in topdressing. We evaluated the chlorophyll content in leaves of common beans, the leaf N content and dry mass weight (MSPA in the flowering of common beans, the number of pods per plant, number of grains per pod, mass of 100 grains, grain yield and final stand of the common beans. The sources of nitrogen fertilizer did not influence, leaf N content, the mass of MSPA and the relative chlorophyll index of common beans. The use of polymerized urea and urea with urease inhibitor, did not produce increases in the number of grains per pod, number of pods per plant, mass of 100 grains and common beans yield compared to traditional sources of N, urea, ammonium sulfate and ammonium nitrate.

Evaluation of inorganic fertilization in cassava crop in the northern region of Costa Rica

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Parménides Furcal-Beriguete

2015-06-01

Full Text Available The study was done in three farms, two of which are located in the canton of San Carlos, district La Fortuna, in volcanic origin soils with moderate fertility (farm Pepin and high fertility (farm Sonafluca and the other in the canton of Los Chiles in ultisols soils of low fertility (farm Laberinto. The objective of this study was to evaluate the effect of methods fertilization on cassava crop, Valencia variety, to obtain for the best alternative in yield and profitability. Four treatments were applied: complete soil fertilization, foliar fertilization only, combination of these two treatments and common fertilization on each farm, using an unrestricted random design with four replications. Fertilizations were made before the five months of age to cover the phases of increased absorption of nutrients. The results obtained in farm Pepin showed p-valor <0,05 in root dry matter at harvest, in first quality cassava and the concentration of some elements in the leaves for the control treatment, this produced the best yield with 16.1 t / ha. In the farm of Sonafluca, the control showed the highest yield with 20.85 t / ha; there were differences in this farm as in Laberinto in dry matter at six months of age. We conclude that the only foliar treatment (commonly used by small producers is the most economical, while the control (application of fertilizers to soil and leaves according to each producer was the best yield.

Angiotensin-Converting Enzymes Play a Dominant Role in Fertility

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Fan Jin

2013-10-01

Full Text Available According to the World Health Organization, infertility, associated with metabolic syndrome, has become a global issue with a 10%–20% incidence worldwide. An accumulating body of evidence has shown that the renin–angiotensin system is involved in the fertility problems observed in some populations. Moreover, alterations in the expression of angiotensin-converting enzyme-1, angiotensin-converting enzyme-2, and angiotensin-converting enzyme-3 might be one of the most important mechanisms underlying both female and male infertility. However, as a pseudogene in humans, further studies are needed to explore whether the abnormal angiotensin-converting enzyme-3 gene could result in the problems of human reproduction. In this review, the relationship between angiotensin-converting enzymes and fertile ability is summarized, and a new procedure for the treatment of infertility is discussed.

Cadmium in fertilizers, soil, crops and foods - the Swedish situation

Energy Technology Data Exchange (ETDEWEB)

Hellstrand, S; Landner, L [Swedish Environmental Research Group (MFG)

1998-03-01

The aim of this report is to review available information on the fluxes of cadmium (Cd) to agricultural soils and crops in Sweden from phosphorus fertilizers (P-fertilizer) and other sources, and to discuss how the content of Cd in soil, crops and human food may be influenced by the specific environmental conditions in Sweden, as well as by the agricultural practices used in the country 62 refs, 15 figs, 18 tabs. With 5 page summary in Swedish

EFFECT OF SOIL FERTILITY MANAGEMENT PRACTICES ON NEMATODE DESTROYING FUNGI IN TAITA, KENYA

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Peter M Wachira

2010-10-01

Full Text Available The effect of soil fertility management practices on nematode destroying fungi was investigated for three seasons in Taita, Kenya. The study aimed at identifying soil fertility practice that promoted nematode destroying fungi in the soil. Field experiments were established in Taita district, the treatments comprised of Mavuno fertilizer, Triple super- phosphate and calcium ammonium nitrate (TSP+CAN, cow manure and a control where no amendments were applied. This experiment was replicated in ten farms and repeated in three planting seasons. Isolation of nematode destroying fungi carried out was using the soil sprinkle technique and the isolates were identified using the key described by Cooke and Godfrey (1964. There were significant difference (P= 1.705 x 10-06 in occurrence of the nematode destroying fungi between soil fertility treatments. The highest mean (1.6 occurrence of nematode destroying fungi was recorded in soils amended with cow manure and the least (0.7 was recorded in soils from the control plots. A mean of 0.78 was recorded in soils from both TSP+CAN and Mavuno fertilizers. Plots amended with cow manure presented the highest diversity of nematodes followed by the control, then TSP+CAN and least in Mavuno with shannon indices of 0.34, 0.15, 0.13 and 0.11 respectively. Sixty percent of all the isolated nematode destroying fungi genera were from plots treated with cow manure and only twenty percent were from plots amended with the inorganic fertilizer. The control plots recorded higher number of nematode destroying fungi compared to the soils that received inorganic fertilizers.

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

Ionizing Radiation Dose Due to the Use of Agricultural Fertilizers

International Nuclear Information System (INIS)

Umisedo, Nancy K.; Okuno, Emico; Medina, Nilberto H.; Colacioppo, Sergio; Hiodo, Francisco Y.

2008-01-01

The transference of radionuclides from the fertilizers to/and from soils to the foodstuffs can represent an increment in the internal dose when the vegetables are consumed by the human beings. This work evaluates the contribution of fertilizers to the increase of radiation level in the environment and of dose to the people. Samples of fertilizers, soils and vegetables produced in farms located in the neighbourhood of Sao Paulo city in the State of Sao Paulo, Brazil were analysed through gamma spectroscopy. The values of specific activity of 40 K, 238 U and 232 Th show that there is no significant transference of natural radionuclides from fertilizers to the final product of the food chain. The annual committed effective dose due to the ingestion of 40 K contained in the group of consumed vegetables analysed in this work resulted in the very low value of 0.882 μSv

Effects of Organic and Chemical Fertilizers on some Quantitative Traits and Anthocyanin of Roselle under Zabol conditions

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rahman Ebrahimzadeh abdashti

2017-02-01

Full Text Available Introduction: Roselle (Hibiscus sabdariffa L. belongs to the Malvaceae family, and is an annual or biennial plant that cultivated in tropical and subtropical regions for its stem fibers, eatable calyces, leaves and grains. Roselle is resistant to relatively high temperatures throughout the growing and fruiting times. Continuous use of chemical fertilizers destroys the soil ecological balance, reduces soil fertility and groundwater pollution is caused. In contrast, organic fertilizers are very safe for human health and the environment. It is made by recycling organic material as plant and animals waste, and food scraps in a controlled process. Of the organic fertilizers can be noted to compost, vermicompost, cattle manure andhumic acid. The study was carried out in order to sustainable agriculture. The aim of this study was to investigate the effects of organic and chemical fertilizers on some quantitative traits and anthocyanin of roselle. Materials and Methods: The experiment was performed in complete randomized block design with ten treatments and four replications in research field of agricultural faculty, university of zabol. The treatments included T1: control, T2: NPK in a ratio of 2:1:1 (300 kg ha-1, T3: cattle manure (20 t ha-1, T4: compost (10 t ha-1, T5: vermicompost (5 t ha-1, T6: humic acid foliar in a ratio of 1.5 per thousands, T7: 50% of T2 and T6 , T8: 50% of T3 and T6, T9: 50% of T4 and T6 and T10: 50% of the T5 and T6. Five plants were chosen and an average of five plants was calculated as the single plant for measuring of variables that included the height, number of branches, stem diameter, shoot fresh weight, number of fruits per plant, fruit weight, number of seeds per plant, fresh and dry weights of sepals, inflorescence length, length and diameter of fruit. Method of Wagner has been used for the anthocyanin measurement. Results and Discussion: Results of this research showed that the application of different fertilizers

Is Buddhism the low fertility religion of Asia?

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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.

Demographic and fertility characteristics of 4 squatter settlements.

Science.gov (United States)

Yusof, K; Zulkifli, S N

1985-01-01

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

The influence of rural-urban migration on migrant's fertility behavior in Cameroon.

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Lee, B S

1992-01-01

Preliminary analysis of Cameroon fertility data suggests that rural stayers do not have a significantly higher fertility than rural-urban migrants in contrast to hypotheses suggested in the literature. Bongaarts and Caldwell both suggest that modernization plays a role in African fertility and migration patterns by increasing exposure to childbearing. Supply constraints are changed by higher levels of education, short duration of postpartum abstinence, less prevalence of polygamy, and more stable marriages. The influence of relatives may be weaker and the fear of losing a husband greater, which influence earlier returns to sexual relations. Because the levels of fertility of stayers and movers may be equal does not suggest that movers do not adapt fertility to urban norms. Analysis was conducted with d ata from the 1978 Cameroon World Fertility Survey on 8219 women aged 15-54 years for rural nonmigrants, rural-rural migrants, and rural-urban migrants. Rural-urban migrants were found to be better educated, have fewer cases of infertility, and have more stable first marriages. Descriptive statistics are provided for migrants and nonmigrants. Cross classification analysis shows that fertility is not lower for women with higher education, even when migration status is controlled for. Multivariate regression results in an autoregressive model in a first difference form indicated that the fertility rate of rural-urban migrant women was significantly higher than that of rural staryers during the period of 5-9 years after migration. The urban effect acts to reduce migrants' fertility by about .13 births. Comparisons are made with Mexican and Korean migration behavior, which reflect decreased fertility after migration of 1.5 births and 2.6 births, respectively. The suggestion is that the fertility-increasing effect of supply conditions in Cameroon is significantly offset by the fertility-depressing adaptation effect of migration to urban areas. It is expected that

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.)

Structural and diffusion effects in the Dutch fertility transition, 1870-1940

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Hilde Bras

2014-01-01

Full Text Available Background: Ever since the Princeton European Fertility Project, structural and diffusion effects on fertility behavior have been juxtaposed. However, we still hardly know what the relative effects were of shifting socio-economic conditions and shifts in sociability in explaining the historical fertility decline. Objective: To what extent and how did structural and diffusion effects play a role in the adoption of fertility control in the Dutch historical fertility transition? Methods: A national data set was used with more than 3,000 maternity histories of married Dutch women aged 15-50, whose reproductive careers took place between 1870 and 1940. Apart from husbands' occupations, characteristics of the set of couples' marriage witnesses were included to measure their social networks. Cox regression analyses of age at last birth and negative binomial regressions of net family size were conducted. Results: Results indicate that unskilled laborers and farm laborers were laggards in the practice of fertility control during the Dutch fertility transition. Besides SES differentials, differences in couples' social networks were important in explaining fertility behavior. Those who had networks consisting of lateral kin, age peers, and people of urban background stopped childbearing earlier and had smaller families than other couples did. Particularly the presence of lateral kin of the bride and of female witnesses was strongly associated with smaller family size. Conclusions: The evidence lends support for so-called "blended diffusion models" and suggests that the fertility transition must be understood as much from the viewpoint of changed cost-benefit calculations related to structural changes, as from shifting patterns of sociability associated with the decline of patriarchy and the increasing lateralization and age homophily of people's social networks.

Organic fertilization in cherry tomato plants

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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.

INCREASING FISH PRODUCTIVITY OF POND ECOSYSTEMS BY FERTILIZING THEM WITH DISTILLER'S GRAINS

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N. Tson’

2015-03-01

Full Text Available Purpose. To study fish culture parameters of young-of-the-year carp in the conditions of industrial fish-growing ponds when applying experimental repeated fertilization with distiller’s grain. Methodology. The study was conducted in industrial fish-growing ponds. The wastes of alcohol industry – the distiller’s grain as organic fertilizer was gradually introduced into ponds at following amounts: first application – 1,0 t/ha, second application in 10 days – 0,5 t/ha, third application in 12 days – 0,5 t/ha. The control ponds were fertilized with humus (2 t/ha. Young-of-the-year carp (Cyprinus carpio were grown in monoculture at stocking density of 30 000 fish/ha. In addition, 100 kg/ha of lime were applied during the culture season in the experiment and control. Fertilization with humus and application of lime in ponds, hydrochemical studies, sampling and processing of hydrobiological samples, fish culturing and statistical studies were carried out according to standard methods. Findings. Gradual fertilizing with distiller’s grain (to the total 2 t/ha gave the possibility to create favorable hydrochemical and hydrobiological regimes. An average daily growth in the experimental fish groups of 0,44 ± 0,09 g/day that was similar to in the control (0,45 ± 0,11 g/day with positive significant correlation between them (r = 0,97; p <0,001 was achieved. The performed measures gave a possibility to obtain fish productivity in the experimental variant 10.7% more than in the control. An economic effect of 14.3% cost reduction for fertilizing ponds was achieved. Originality. For the first time we presented the results of fish culture and biological parameters of young-of-the-year carp in industrial ponds when applying 3-time fertilization with distiller’s grain. Practical Value. The obtained results are the basis for the broad use of non-traditional organic fertilizer – distiller’s grain in industrial ponds, when growing young

Fertility, immigration, and the fight against climate change.

Science.gov (United States)

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

2017-10-01

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

Women and postfertilization effects of birth control: consistency of beliefs, intentions and reported use

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Kim Han S

2005-11-01

Full Text Available Abstract Background This study assesses the consistency of responses among women regarding their beliefs about the mechanisms of actions of birth control methods, beliefs about when human life begins, the intention to use or not use birth control methods that they believe may act after fertilization or implantation, and their reported use of specific methods. Methods A questionnaire was administered in family practice and obstetrics and gynecology clinics in Salt Lake City, Utah, and Tulsa, Oklahoma. Participants included women ages 18–50 presenting for any reason and women under age 18 presenting for family planning or pregnancy care. Analyses were based on key questions addressing beliefs about whether specific birth control methods may act after fertilization, beliefs about when human life begins, intention to use a method that may act after fertilization, and reported use of specific methods. The questionnaire contained no information about the mechanism of action of any method of birth control. Responses were considered inconsistent if actual use contradicted intentions, if one intention contradicted another, or if intentions contradicted beliefs. Results Of all respondents, 38% gave consistent responses about intention to not use or to stop use of any birth control method that acted after fertilization, while 4% gave inconsistent responses. The corresponding percentages for birth control methods that work after implantation were 64% consistent and 2% inconsistent. Of all respondents, 34% reported they believed that life begins at fertilization and would not use any birth control method that acts after fertilization (a consistent response, while 3% reported they believed that life begins at fertilization but would use a birth control method that acts after fertilization (inconsistent. For specific methods of birth control, less than 1% of women gave inconsistent responses. A majority of women (68% or greater responded accurately about the

Sperm motility of externally fertilizing fish and amphibians.

Science.gov (United States)

Browne, R K; Kaurova, S A; Uteshev, V K; Shishova, N V; McGinnity, D; Figiel, C R; Mansour, N; Agney, D; Wu, M; Gakhova, E N; Dzyuba, B; Cosson, J

2015-01-01

We review the phylogeny, sperm competition, morphology, physiology, and fertilization environments of the sperm of externally fertilizing fish and amphibians. Increased sperm competition in both fish and anurans generally increases sperm numbers, sperm length, and energy reserves. The difference between the internal osmolarity and iconicity of sperm cells and those of the aquatic medium control the activation, longevity, and velocity of sperm motility. Hypo-osmolarity of the aquatic medium activates the motility of freshwater fish and amphibian sperm and hyperosmolarity activates the motility of marine fish sperm. The average longevity of the motility of marine fish sperm (~550 seconds) was significantly (P amphibian sperm in general and anurans reversion from internal to external fertilization. Our findings provide a greater understanding of the reproductive biology of externally fertilizing fish and amphibians, and a biological foundation for the further development of reproduction technologies for their sustainable management.

Adrenal hormones in human follicular fluid.

Science.gov (United States)

Jimena, P; Castilla, J A; Peran, F; Ramirez, J P; Vergara, F; Molina, R; Vergara, F; Herruzo, A

1992-11-01

Considerable evidence indicates that adrenal hormones may affect gonadal function. To assess the role of some adrenal hormones in human follicular fluid and their relationship with the ability of the oocyte to be fertilized and then to cleave in vitro, cortisol and dehydroepiandrosterone sulfate were measured in follicular fluid obtained at the time of oocyte recovery for in vitro fertilization from cycles stimulated by clomiphene citrate, human menopausal gonadotropin and human chorionic gonadotropin. Thirty-six follicular fluid containing mature oocyte-corona-cumulus complexes and free of visible blood contamination were included in this study. There was no significant difference in follicular fluid dehydroepiandrosterone sulfate concentration between follicles with oocytes which did or did not fertilize (5.1 +/- 1.1 vs 5.8 +/- 2.0 mumol/l). However, follicular fluid from follicles whose oocytes were not fertilized had levels of cortisol significantly higher than those in follicular fluid from follicles containing successfully fertilized oocytes (406.0 +/- 75.9 vs 339.2 +/- 37.0 nmol/l; p < 0.005). No significant correlations were found between rates of embryo cleavage and cortisol and dehydroepiandrosterone levels in follicular fluid. We conclude that cortisol levels in follicular fluid may provide an index of fertilization outcome, at least in stimulated cycles by clomiphene citrate, human menopausal gonadotropin and human chorionic gonadotropin.

Evaluation of soil and foliar fertilization on wheat yield and quality

International Nuclear Information System (INIS)

Ndiema, A.C.; Maina, M.P.D.; Kamundia, W.J.

2001-01-01

Traditionally wheat farmers in Kenya apply basal compound fertilizer like diammonium phosphate (DAP), Triple super phosphate (TSP). Plants require a considerable number of different elements for optimal growth. One way of supplying these micronutrients is through foliar fertilization. However there was an increase of 71.7% for 40kg N/ha plus bayfolan in Njoro over the control, 61.8% for bayfolan alone a foliar fertilizer, which contain a wide range of plant nutrients. In Molo the control out-yielded all the treatments indicating that planting the crop with DAP is sufficient. Foliar fertilizer was applied directly to the plant leaves to enhance crop yield due to their rapid absorption. The potential of improving yields comes as a result of increase in number of seeds. The objective of this study was to evaluate the effects of foliar fertilizer on wheat yield when used alone or in combination with soil-applied fertilizers. Byfolan is a fast acting fertilizer with nutrients rapidly becoming available to the plant. The composition of Bayfolan includes N (11%), P (8%), K (6%), Fe (0.019%), Mn (0.016%). Zn (0.0061% ), Co (0.00035%), Mo (0.00009%), sodium, sulphur, vitamin B 1 and growth hormones. The design was RCBD with nine (9) treatments and three (3) replications. The treatments included control, 20kg N/ha, 40kg N/ha, 80kg N/ha, Bayfolan foliar, 20kg N/ha + Baylon a foliar, 40kg N/ha + Bayfolan foliar, 20kg N/ha urea in solution form, 20kg N/ha urea in solution form + Bayfolan foliar. DAP was applied at the rate of 130kg/ha, as a blanket treatment at planting timeto provide N and P for initial growth. Significant difference in spike density and kernel weight at 5% level was observed at farms in Njoro but not at farms in Molo. (author)

Recombinant follitropin alfa/lutropin alfa in fertility treatment

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Ahmed Gibreel

2009-12-01

Full Text Available Ahmed Gibreel1, Siladitya Bhattacharya21School of Medicine and Dentistry, University of Aberdeen; 2Aberdeen Maternity Hospital, Aberdeen, UKAbstract: Recombinant human follicle stimulating hormone (rFSH and luteinizing hormone (LH, also known as follitropin alpha and lutropin alpha, are manufactured by genetic engineering techniques which ensure high quality and batch to batch consistency. Follitropin alpha can be used for controlled ovarian hyperstimulation in assisted reproduction, ovulation induction for WHO group I and II anovulatory infertility and in men with hypogonadotrophic hypogonadism (HH or idiopathic oligo-asthenospermia. Current evidence suggests superiority of urinary human menopausal gonadotropin (HMG over follitropin alpha in controlled ovarian hyperstimulation for IVF in terms of live birth rate per couple. Addition of lutropin to follitropin alpha in an unselected IVF population does not appear to confer any benefit; however, it may have a role in ovulation induction in women with hypothalamic hypogonadism. Urinary HMG preparations (especially currently available highly purified preparations are more cost effective than rFSH in terms of cost per ongoing pregnancy. However, women using rFSH injection pen devices have higher levels of satisfaction as compared to those using urinary HMG by means of conventional syringes.Keywords: infertility, follicle stimulating hormone, luteinizing hormone, follitropin alpha, lutropin alpha, in-vitro fertilization, urinary gonadotrophins

Prostasomes--their effects on human male reproduction and fertility.

Science.gov (United States)

Burden, H P; Holmes, C H; Persad, R; Whittington, K

2006-01-01

The prostate is a glandular male accessory sex organ vital for normal fertility. It provides the prostatic component of seminal plasma which nourishes and protects sperm following ejaculation. Prostasomes are small (40-500 nm) membrane-bound vesicles produced by epithelial cells lining the prostate acini and are a component of prostatic secretions. Although the existence of these particles has been known for many years, their full function and relevance to reproductive health are largely unknown. Proteomic studies have shown a wide range of proteins (enzymes, structural proteins and novel, unannotated proteins) present in or on the surface of prostasomes providing them with a diverse nature. Interestingly prostasomes are able to fuse with sperm, this event and the associated transfer of proteins lies at the heart of many of their proposed functions. Sperm motility is increased by the presence of prostasomes and their fusion prevents premature acrosome reactions. Prostasomes have been shown to aid protection of sperm within the female reproductive tract because of immunosuppressive, antioxidant and antibacterial properties. Clinically these functions imply a role for prostasomes in male factor infertility. However, the very functions that promote fertility may have negative connotations in later life; recent work has suggested that prostasomes are involved in prostate cancer. Clearly more work is needed to clarify the role of these novel particles and their impact on men's health.

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

Science.gov (United States)

Jensen, Allan; Sharif, Heidi; Frederiksen, Kirsten; Kjaer, Susanne Krüger

2009-02-05

To examine the effects of fertility drugs on overall risk of ovarian cancer using data from a large cohort of infertile women. Population based cohort study. Danish hospitals and private fertility clinics. 54,362 women with infertility problems referred to all Danish fertility clinics during 1963-98. The median age at first evaluation of infertility was 30 years (range 16-55 years), and the median age at the end of follow-up was 47 (range 18-81) years. Included in the analysis were 156 women with invasive epithelial ovarian cancer (cases) and 1241 subcohort members identified in the cohort during follow-up in 2006. Effect of four groups of fertility drugs (gonadotrophins, clomifene citrate, human chorionic gonadotrophin, and gonadotrophin releasing hormone) on overall risk of ovarian cancer after adjustment for potential confounding factors. Analyses within cohort showed no overall increased risk of ovarian cancer after any use of gonadotrophins (rate ratio 0.83, 95% confidence interval 0.50 to 1.37), clomifene (1.14, 0.79 to 1.64), human chorionic gonadotrophin (0.89, 0.62 to 1.29), or gonadotrophin releasing hormone (0.80, 0.42 to 1.51). Furthermore, no associations were found between all four groups of fertility drugs and number of cycles of use, length of follow-up, or parity. No convincing association was found between use of fertility drugs and risk of ovarian cancer.

Soil heterogeneity and soil fertility gradients in smallholder agricultural systems of the east african highlands

NARCIS (Netherlands)

Tittonell, P.A.; Muriuki, A.; Klapwijk, C.J.; Shepherd, K.D.; Coe, R.; Vanlauwe, B.

2013-01-01

Heterogeneity in soil fertility in these smallholder systems is caused by both inherent soil-landscape and human-induced variability across farms differing in resources and practices. Interventions to address the problem of poor soil fertility in Africa must be designed to target such diversity and

Effects of fertilizers used in agricultural fields on algal blooms

Science.gov (United States)

Chakraborty, Subhendu; Tiwari, P. K.; Sasmal, S. K.; Misra, A. K.; Chattopadhyay, Joydev

2017-06-01

The increasing occurrence of algal blooms and their negative ecological impacts have led to intensified monitoring activities. This needs the proper identification of the most responsible factor/factors for the bloom formation. However, in natural systems, algal blooms result from a combination of factors and from observation it is difficult to identify the most important one. In the present paper, using a mathematical model we compare the effects of three human induced factors (fertilizer input in agricultural field, eutrophication due to other sources than fertilizers, and overfishing) on the bloom dynamics and DO level. By applying a sophisticated sensitivity analysis technique, we found that the increasing use of fertilizers in agricultural field causes more rapid algal growth and decreases DO level much faster than eutrophication from other sources and overfishing. We also look at the mechanisms how fertilizer input rate affects the algal bloom dynamics and DO level. The model can be helpful for the policy makers in determining the influential factors responsible for the bloom formation.

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

Directory of Open Access Journals (Sweden)

James J Elser

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

Effect of Localities and organic Fertilizers on Yield in Conditions of Organic Farming

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Jiri Antosovsky

2017-01-01

Full Text Available Nitrogen fertilization cannot be used by actual needs of plants during vegetation in organic farming. The proper crop rotation and harmonic nutrition are necessary for good and quality products. The methods of treatment are mainly realized by cultivation of green manure crop and fertilizing by organic fertilizers. The aim of the long-term experiment was to evaluate the effect of different localities and different organic fertilizers on crop yield in organic farming. Variants of fertilization included in the experiment are: 1. Unfertilized control, 2. Green manure, 3. Green manure + renewable external sources, 4. Green manure + renewable external sources + auxiliary substances, 5. Green manure + farm fertilizers, 6. Green manure + farm fertilizers + auxiliary substances. The experiment started by sowing of winter wheat so green manure crop was not grown in the first experimental year. The highest yield of winter wheat grain coming from the first year of the experiment was observed on the variant with renewable external sources (digestate. Average grain yield on this variant was about 7.12 t/ha (up to 0.74 t/ha increased than the unfertilized control. Average yield of potatoes from the second year of the experiment was the highest after combination with green manure + renewable external sources (compost + digestate + auxiliary substances. This variant achieved yield about 34.08 t/ha, which is increased by 9.35 t/ha compared to the control variant. Results from this two-year experiment showed that the most suitable combination of fertilization with or without green manure crop is compost + digestate. These results were probably caused by higher content of nitrogen in organic fertilizers (compost + digestate used in this variant compared to other variants. Statistical difference of achieved yields was observed between each experimental station in both experimental years.

From menarche to menopause: the fertile life span of celiac women.

Science.gov (United States)

Santonicola, Antonella; Iovino, Paola; Cappello, Carmelina; Capone, Pietro; Andreozzi, Paolo; Ciacci, Carolina

2011-10-01

We evaluated menopause-associated disorders and fertile life span in women with celiac disease (CD) under untreated conditions and after long-term treatment with a gluten-free diet. The participants were 33 women with CD after menopause (untreated CD group), 25 celiac women consuming a gluten-free diet at least 10 years before menopause (treated CD group), and 45 healthy volunteers (control group). The Menopause Rating Scale questionnaire was used to gather information on menopause-associated disorders. The International Physical Activity Questionnaire was used to acquire information on physical activity. Untreated celiac women had a shorter duration of fertile life span than did the control women because of an older age of menarche and a younger age of menopause (P menopause causes a shorter fertile period in untreated celiac women compared with control women. A gluten-free diet that started at least 10 years before menopause prolongs the fertile life span of celiac women. The perception of intensity of hot flushes and irritability is more severe in untreated celiac women than in controls. Low physical exercise and/or poorer quality of life frequently reported by untreated celiac women might be the cause of reduced discomfort tolerance, thus increasing the subjective perception of menopausal symptoms.

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

Identification of Diarrheagenic Escherichia coli Strains from Avian Organic Fertilizers

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Juan Puño-Sarmiento

2014-08-01

Full Text Available The Brazilian poultry industry generates large amounts of organic waste, such as chicken litter, which is often used in agriculture. Among the bacteria present in organic fertilizer are members of the Enterobacteriaceae family. The objective of this study was to detect the presence of diarrheagenic Escherichia coli (DEC strains in avian organic fertilizer, and assess the potential damage they can cause in humans due to antimicrobial resistance. The presence of DEC pathotypes and phylogenetic groups were detected by multiplex-PCR. Phenotypic assays, such as tests for adhesion, cytotoxicity activity, biofilm formation and especially antimicrobial susceptibility, were performed. Fifteen DEC strains from 64 E. coli were isolated. Among these, four strains were classified as enteropathogenic (EPEC; 6.2%, three strains as Shiga toxin-producing (STEC; 4.7%, 10 strains as enteroaggregative (EAEC; 12.5%, but two of these harbored the eaeA gene too. The low number of isolated strains was most likely due to the composting process, which reduces the number of microorganisms. These strains were able to adhere to HEp-2 and HeLa cells and produce Shiga-toxins and biofilms; in addition, some of the strains showed antimicrobial resistance, which indicates a risk of the transfer of resistance genes to human E. coli. These results showed that DEC strains isolated from avian organic fertilizers can cause human infections.

Identification of diarrheagenic Escherichia coli strains from avian organic fertilizers.

Science.gov (United States)

Puño-Sarmiento, Juan; Gazal, Luis Eduardo; Medeiros, Leonardo P; Nishio, Erick K; Kobayashi, Renata K T; Nakazato, Gerson

2014-08-28

The Brazilian poultry industry generates large amounts of organic waste, such as chicken litter, which is often used in agriculture. Among the bacteria present in organic fertilizer are members of the Enterobacteriaceae family. The objective of this study was to detect the presence of diarrheagenic Escherichia coli (DEC) strains in avian organic fertilizer, and assess the potential damage they can cause in humans due to antimicrobial resistance. The presence of DEC pathotypes and phylogenetic groups were detected by multiplex-PCR. Phenotypic assays, such as tests for adhesion, cytotoxicity activity, biofilm formation and especially antimicrobial susceptibility, were performed. Fifteen DEC strains from 64 E. coli were isolated. Among these, four strains were classified as enteropathogenic (EPEC; 6.2%), three strains as Shiga toxin-producing (STEC; 4.7%), 10 strains as enteroaggregative (EAEC; 12.5%), but two of these harbored the eaeA gene too. The low number of isolated strains was most likely due to the composting process, which reduces the number of microorganisms. These strains were able to adhere to HEp-2 and HeLa cells and produce Shiga-toxins and biofilms; in addition, some of the strains showed antimicrobial resistance, which indicates a risk of the transfer of resistance genes to human E. coli. These results showed that DEC strains isolated from avian organic fertilizers can cause human infections.

Arbuscular mycorrhizal fungi are an alternative to the application of chemical fertilizer in the production of the medicinal and aromatic plant Coriandrum sativum L.

Science.gov (United States)

Oliveira, Rui S; Ma, Ying; Rocha, Inês; Carvalho, Maria F; Vosátka, Miroslav; Freitas, Helena

2016-01-01

The widespread use of agrochemicals is detrimental to the environment and may exert harmful effects on human health. The consumer demand for organic food plants has been increasing. There is thus a rising need for alternatives to agrochemicals that can foster sustainable plant production. The aim of this study was to evaluate the potential use of an arbuscular mycorrhizal (AM) fungus as an alternative to application of chemical fertilizer for improving growth performance of the medicinal and aromatic plant Coriandrum sativum. Plants were inoculated with the AM fungus Rhizophagus irregularis BEG163 and/or supplemented with a commercial chemical fertilizer (Plant Marvel, Nutriculture Bent Special) in agricultural soil. Plant growth, nutrition, and development of AM fungus were assessed. Plants inoculated with R. irregularis and those supplemented with chemical fertilizer displayed significantly improved growth performances when compared with controls. There were no significant differences in total fresh weight between plants inoculated with R. irregularis or those supplemented with chemical fertilizer. Leaf chlorophyll a + b (82%), shoot nitrogen (44%), phosphorus (254%), and potassium (27%) concentrations increased in plants inoculated with R. irregularis compared to controls. Application of chemical fertilizer inhibited root mycorrhizal colonization and the length of the extraradical mycelium of R. irregularis. Inoculation with R. irregularis was equally or more efficient than application of chemical fertilizer in promoting growth and nutrition of C. sativum. AM fungi may thus contribute to improve biologically based production of food plants and reduce the dependence on agrochemicals in agriculture.

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.

Population differences in self-fertility in the "self-incompatible" milkweed Asclepias exaltata (Asclepiadaceae).

Science.gov (United States)

Lipow, S R; Broyles, S B; Wyatt, R

1999-08-01

Individual plants of Asclepias exaltata (Asclepiadaceae) typically express an unusual self-incompatibility system under single-gene control. Hand-pollinations performed in six natural populations detected occasional self-fertile plants. The frequency of self-fertile individuals ranged from 0 to 34.0% and differed significantly among populations. Self-fertility appears to be under genetic control, as the ability of most plants (80.0 %) to set fruit following self-pollinations was identical under natural and greenhouse conditions. Seed- and fruit-set, however, were significantly lower from self- vs. cross-pollinations. Allozyme analysis of the population with the highest frequency of self-fertility revealed that adult plants were not significantly inbred. Finally, fruit-set following within-population cross-pollinations did not differ from that following wide, between-population cross-pollinations.

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

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.

Fertility, Household’s size and Poverty in Nepal

OpenAIRE

François Libois; Vincent Somville

2014-01-01

Population control policies keep on attracting a lot of attention. The main argument in favour of a reduction in fertility rates, is that having more children contributes directly to a household’s poverty. Using the last three rounds of the Nepal Living Standards Surveys, we investigate the links between household’s fertility decisions and their consequent achievements in incomes and consumption. In contradiction with the popular presumptions, we find that having more children does not have a...

Influence of Chicken Manure Fertilization on Antibiotic-Resistant Bacteria in Soil and the Endophytic Bacteria of Pakchoi

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Qingxiang Yang

2016-06-01

Full Text Available Animal manure is commonly used as fertilizer for agricultural crops worldwide, even though it is believed to contribute to the spread of antibiotic resistance from animal intestines to the soil environment. However, it is unclear whether and how there is any impact of manure fertilization on populations and community structure of antibiotic-resistant endophytic bacteria (AREB in plant tissues. To investigate the effect of manure and organic fertilizer on endophytic bacterial communities, pot experiments were performed with pakchoi grown with the following treatments: (1 non-treated; (2 chicken manure-treated and (3 organic fertilizer-treated. Manure or organic fertilizer significantly increased the abundances of total cultivable endophytic bacteria (TCEB and AREB in pakchoi, and the effect of chicken manure was greater than that of organic fertilizer. Further, 16S rDNA sequencing and the phylogenetic analysis indicated that chicken manure or organic fertilizer application increased the populations of multiple antibiotic-resistant bacteria (MARB in soil and multiple antibiotic-resistant endophytic bacteria (MAREB in pakchoi. The identical multiple antibiotic-resistant bacterial populations detected in chicken manure, manure- or organic fertilizer-amended soil and the vegetable endophytic system were Brevundimonas diminuta, Brachybacterium sp. and Bordetella sp., suggesting that MARB from manure could enter and colonize the vegetable tissues through manure fertilization. The fact that some human pathogens with multiple antibiotic resistance were detected in harvested vegetables after growing in manure-amended soil demonstrated a potential threat to human health.

Effects of Different Fertilizing Formulae on Potato

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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

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.

POLAND AND UKRAINE IN THE LIGHT OF PARADYSZ'S PERIOD FERTILITY MODEL

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J. Paradysz

2015-04-01

Full Text Available The article reflects research issues, which are currently considered to be of utmost importance in methodology of period fertility analysis. In the cohort analysis we dispose many possibilities to describe human reproduction process. The period analysis is not so reach and we would like to use the same methods in the both one. Many years ago one of us have proposed a decomposition of the period total fertility rate in order to calculate period “theoretical” birth intervals. Combining the two systems demographic analysis (parity progression ration and increment–decrement tables we decompose the “classic” total fertility rate (TFR on the last and non–last children in period analysis.

Effect of Vitrification on Sperm Parameters and Apoptosis in Fertile Men

OpenAIRE

M Adib; M Ramezani; MA Khalili

2011-01-01

Introduction & Objective: Today, cryopreservation of the human sperm is a common technique for treating infertility. It has been indicated that cryopreservation by different methods decrease the sperm motility and viability in fertile men, but still effect of freezing of the sperm by vitrification method have not been evaluated on sperm parameters and apoptosis. The aim of this study was to evaluate the effect of vitrification of sperm of fertile men on different sperm parameters (motility, m...

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

Science.gov (United States)

Chin Ptc

1985-12-01

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

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)

Control efficacy of Ca-containing foliar fertilizers on bitter pit in bagged 'Fuji' apple and effects on the Ca and N contents of apple fruits and leaves.

Science.gov (United States)

Yu, Xian-Mei; Wang, Jin-Zheng; Nie, Pei-Xian; Xue, Xaio-Min; Wang, Gui-Ping; An, Miao

2018-04-20

The preharvest application of Ca-containing foliar fertilizers can reduce bitter pit (BP) incidence in apples and improve fruit quality by increasing the Ca content and decreasing both the N content and the N/Ca ratio in fruits. In this study, we aimed to investigate the control efficacy of Ca-containing fertilizers on BP incidence and the effects on the Ca and N contents in bagged 'Fuji' apple by spraying the foliar fertilizer containing calcium chloride (CaCl 2 ), calcium nitrate [Ca(NO 3 ) 2 ] or calcium formate [Ca(HCOO) 2 ] at early stage [5 days after full bloom (DAFB) + 40 DAFB] and at late stage (80 DAFB + 125 DAFB). The BP incidences were reduced significantly with the reduce percentage of 43.2~73.0%, and the efficacy of spraying at early stage was significantly higher than that of spraying at late stage. The Ca content of bagged apple fruits was increased while the N content and N/Ca ratio were decreased after spraying Ca-containing foliar fertilizers, however, the Ca content, N content and N/Ca ratio of apple leaves were differentially influenced. The foliar fertilizer containing CaCl 2, Ca(NO 3 ) 2 or Ca(HCOO) 2 could be used at early stage to control BP in apple and improve the quality of bagged apple fruits. This article is protected by copyright. All rights reserved.

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.

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

Efeito da solarização, adubação química e orgânica no controle de nematóides em alface sob cultivo protegido Effect of solarization, chemical and organic fertilization on the control of nematode on greenhouse lettuce

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Marlene G da Silva

2006-12-01

Full Text Available Os efeitos da solarização do solo associados à adubação no controle de nematóides e na produtividade da alface cultivar "Verônica" foram avaliados em solo naturalmente infestado. Dois experimentos foram conduzidos, um com e outro sem solarização, em casa de vegetação, ambos com cinco tratamentos: adubação orgânica; nitrogênio na forma amoniacal (NH4; adubação com NPK; adubação orgânica mais NPK; testemunha (sem adubação. No experimento solarizado, o solo foi coberto durante 132 dias com filme plástico transparente. A população de nematóides foi avaliada em duas camadas (0-10 cm e 10-20 cm, e as coletas de solo foram feitas em três épocas (antes da implantação do experimento; após a solarização; após a colheita. O delineamento experimental foi o de blocos ao acaso com três repetições em parcelas sub-subdivididas, com medidas no espaço e no tempo (5 adubações x 2 camadas x 3 épocas, e a comparação entre experimentos foi feita pela análise conjunta. O efeito da solarização sobre o controle de nematóides dependeu da adubação e camada do solo. A solarização reduziu a população de nematóides na camada de 0-10 cm em todos os tratamentos de adubação. A solarização associada ao NH4 reduziu a diversidade na camada de 10-20 cm. A solarização combinada às adubações orgânica, N-NH4, NPK e orgânica mais NPK reduziu de maneira eficiente o número de galhas, o número de massas de ovos e a população de nematóides fitoparasitas nas raízes, em especial de Meloidogyne spp. Solarização combinada à adubação orgânica apresenta potencial para controle de nematóides e redução do uso de agrotóxicos.The effect of soil solarization and fertilization was evaluated for nematode control in 'Veronica' lettuce in naturally infested soil. The two greenhouse experiments consisted of five fertilization treatments: organic fertilization; ammoniacal nitrogen (ammonium sulphate; NPK fertilization; organic

Total fertilization failure and idiopathic subfertility

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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.

Establishment of a rice-duck integrated farming system and its effects on soil fertility and rice disease control

Science.gov (United States)

Teng, Qing; Hu, Xue-Feng; Cheng, Chang; Luo, Zhi-Qing; Luo, Fan

2015-04-01

Rice-duck integrated farming is an ecological farming system newly established in some areas of southern China . It was reported that the ducks walking around the paddy fields is beneficial to control weed hazards and reduce rice pests and diseases. To study and evaluate the effects of the rice-duck integrated farming on soil fertility and rice disease control, a field experiment of rice cultivation was carried out in the suburb of Shanghai in 2014. It includes a treatment of raising ducks in the fields and a control without ducks. The treatment was implemented by building a duck coop nearby the experimental fields and driving 15 ducks into a plot at daytime since the early stage of rice growth. Each plot is 667 m2 in area. The treatment and control were replicated for three times. No any herbicides, pesticides, fungicides and chemical fertilizers were applied during the experiment to prevent any disturbance to duck growing and rice weed hazards and disease incidences from agrochemicals. The results are as follows: (1) The incidences of rice leaf rollers (Cnaphalocrocis medinalis) and stem borers treated with ducks, 0.45%and 1.18% on average, respectively, are lower than those of the control, 0.74% and 1.44% on average, respectively. At the late stage of rice growth, the incidence of rice sheath blight treated with ducks, 13.15% on average, is significantly lower than that of the control, 16.9% on average; and the incidence of rice planthoppers treated with ducks, 11.3 per hill on average, is also significantly lower than that of the control, 47.4 per hill on average. (2) The number of weeds in the plots treated with ducks, 8.3 per m2 on average, is significantly lower than that of the control, 87.5 m2 on average. (3) Raising ducks in the fields could also enhance soil enzyme activity and nutrient status. At the late stage of rice growth, the activities of urease, phosphatase, sucrase and catalase in the soils treated with ducks are 1.39 times, 1.40 times, 1

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

Modeling Human Error Mechanism for Soft Control in Advanced Control Rooms (ACRs)

Energy Technology Data Exchange (ETDEWEB)

Aljneibi, Hanan Salah Ali [Khalifa Univ., Abu Dhabi (United Arab Emirates); Ha, Jun Su; Kang, Seongkeun; Seong, Poong Hyun [KAIST, Daejeon (Korea, Republic of)

2015-10-15

To achieve the switch from conventional analog-based design to digital design in ACRs, a large number of manual operating controls and switches have to be replaced by a few common multi-function devices which is called soft control system. The soft controls in APR-1400 ACRs are classified into safety-grade and non-safety-grade soft controls; each was designed using different and independent input devices in ACRs. The operations using soft controls require operators to perform new tasks which were not necessary in conventional controls such as navigating computerized displays to monitor plant information and control devices. These kinds of computerized displays and soft controls may make operations more convenient but they might cause new types of human error. In this study the human error mechanism during the soft controls is studied and modeled to be used for analysis and enhancement of human performance (or human errors) during NPP operation. The developed model would contribute to a lot of applications to improve human performance (or reduce human errors), HMI designs, and operators' training program in ACRs. The developed model of human error mechanism for the soft control is based on assumptions that a human operator has certain amount of capacity in cognitive resources and if resources required by operating tasks are greater than resources invested by the operator, human error (or poor human performance) is likely to occur (especially in 'slip'); good HMI (Human-machine Interface) design decreases the required resources; operator's skillfulness decreases the required resources; and high vigilance increases the invested resources. In this study the human error mechanism during the soft controls is studied and modeled to be used for analysis and enhancement of human performance (or reduction of human errors) during NPP operation.

Modeling Human Error Mechanism for Soft Control in Advanced Control Rooms (ACRs)

International Nuclear Information System (INIS)

Aljneibi, Hanan Salah Ali; Ha, Jun Su; Kang, Seongkeun; Seong, Poong Hyun

2015-01-01

To achieve the switch from conventional analog-based design to digital design in ACRs, a large number of manual operating controls and switches have to be replaced by a few common multi-function devices which is called soft control system. The soft controls in APR-1400 ACRs are classified into safety-grade and non-safety-grade soft controls; each was designed using different and independent input devices in ACRs. The operations using soft controls require operators to perform new tasks which were not necessary in conventional controls such as navigating computerized displays to monitor plant information and control devices. These kinds of computerized displays and soft controls may make operations more convenient but they might cause new types of human error. In this study the human error mechanism during the soft controls is studied and modeled to be used for analysis and enhancement of human performance (or human errors) during NPP operation. The developed model would contribute to a lot of applications to improve human performance (or reduce human errors), HMI designs, and operators' training program in ACRs. The developed model of human error mechanism for the soft control is based on assumptions that a human operator has certain amount of capacity in cognitive resources and if resources required by operating tasks are greater than resources invested by the operator, human error (or poor human performance) is likely to occur (especially in 'slip'); good HMI (Human-machine Interface) design decreases the required resources; operator's skillfulness decreases the required resources; and high vigilance increases the invested resources. In this study the human error mechanism during the soft controls is studied and modeled to be used for analysis and enhancement of human performance (or reduction of human errors) during NPP operation

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 - ...

Effect of Organic Fertilizers on Yield and Yield Components of Safflower (Carthamus tinctorious L.

Directory of Open Access Journals (Sweden)

S. M Azimzadeh

2017-12-01

two different application dates of them on safflower an experiment was conducted at Islamic Azad University of Shirvan, Iran, in growing season of 2012-2013 and 2013-2014. Date of first application was two month prior of planting and date of second application was simultaneous with planting. Amounts of vermicompost included 4, 7 and 10 ton ha-1, municipal solid waste compost included 5, 10 and 15 ton ha-1, cow manure included 20, 33 and 50 ton ha-1, nitrogen chemical fertilizer included 100 kg ha-1 and control. Experiment was conducted as split plot based on randomized complete block design with three replications. Application time of organic fertilizers located in main plots and each one of organic fertilizers levels with nitrogen fertilizer and control as a independent treatment located in subplots. Required rates of different fertilizers were scattered by hand into the plots on 20th Feb then no operation was done until April 21th. On April 21th, main plots which should have been applied fertilization simultaneous with planting were received fertilizers. At this time, all of the plot which have been received fertilizers on Feb 20th plus plots which received fertilizers recently were planted simultaneously. Data were combined analyzed by MSTAT-C software and means were compared with Duncan’s test at the 5% level of probability. Results and Discussion The results showed that in first growing season, fertilizer application before planting caused 12% yield increment of safflower compared with fertilizer application at planting time but in second growing season, fertilizer application at the time of planting caused 12.8% yield increment of safflower compared with fertilizer application before planting. Enough time for manure decomposition can be the reason for this difference. In first year in fertilizer application before planting, all treatments except 10 ton h-1 municipal solid waste compost produced more seed yield than control and chemical fertilizer treatments

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

Effects of various organic and chemical fertilizers on growth indices of basil (Ocimum basilicum L.

Directory of Open Access Journals (Sweden)

S.M.K. Tahami

2016-05-01

Full Text Available In order to develop the high intensive agriculture, more chemical fertilizers are applied to the soil that resulting in soil degradation and environment deterioration. Application of organic manure is an important approach for maintaining and improving the soil fertility and increasing fertilizer use efficiency. Therefore, in order to evaluate the effect of organic manures and chemical fertilizer on growth indices and biological yield of basil (Ocimum basilicum L., an experiment was conducted at Research Station, Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, during growing season of 2008-2009. A complete randomized block design with six treatments and three replications was used. The treatments were: cow manure, sheep manure, chicken manure, vermicompost, chemical NPK fertilizers and control (no fertilizer. The results showed that the use of organic fertilizers significantly increased seed and biological yield of basil compared with chemical fertilizer and control. The maximum and the minimum dry weights were observed at 105 days after planting, in sheep and cow manures, respectively. Gradually during the period of plant growth and development to reproduction phase percent of stem decreased and dry weight of inflorescence increased. The highest and the lowest leaf area index were observed at 90 days after planting, in cow manure and control, respectively, and then decreased in all treatments. The maximum crop growth rate in most of treatments at 90 days after planting was obtained, except the control which plant growth rate was lowest. Net assimilation rate (NAR in most treatments increased until 75 days after planting and then declined. While the highest and the lowest NAR were observed at 75 days after planting in chicken manure and chemical treatment, respectively.

Initial substrate moisture content and storage temperature affects chemical properties of bagged substrates containing controlled release fertilizer at two different temperatures

Science.gov (United States)

Bagged potting mixes can be stored for weeks or months before being used by consumers. Some bagged potting mixes are amended with controlled release fertilizers (CRF). The objective of this research was to observe how initial substrate moisture content and storage temperature affect the chemical p...

[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.

Effect of Gamma Irradiation, Organic and Mineral Fertilizers on Growth, Yield and Fruit Quality of Sweet Pepper

International Nuclear Information System (INIS)

Fath El-Bab, T.Sh.

2014-01-01

Field experiment was carried out for two successive seasons 2011 and 2012, on sweet pepper ( Capsicum annuum L. ) cv. California wonder in the Research Station of Atomic Energy Authority at Inshas, Egypt. This research aimed to evaluate response of sweet pepper to chemical and organic manure (poultry or sheep) fertilizers. Organic manures were treated with gamma rays at the dose of 10 KGy to keep it free from pathogenic organism pests and weed seeds. Growth characters such as plant height, num - ber of leaves, number of stems and dry weight per plant in the two seasons were significantly respond to tested factors. The highest vegetative growth characters were induced by 100% mineral fertilizer. Meanwhile, the lowest vegetative growth characters were recorded by using 100% organic manure as compared to mineral fertilizer. On the other hand dry weight of plants treated with organic manure treatment significantly decreased as compared to mineral fertilizer in the two seasons. Furthermore, using organic manure had enhanced or improved the quality of sweet pepper fruits. In conclusion, mineral fertilizers combined with organic fertilizers were the best treatment resulted in the highest vegetative growth, yield and fruit quality of sweet pepper. This treatment resulted in not only higher total chlorophyll in leave content compared to control plants, but also the highest chemical properties values of fruits, total soluble solids, acidity, vitamin C. and carotenoids in the two seasons. Nitrogen, phosphorus and potassium content non significantly increased with all treatments except that of 100% chemical fertilizer. The improvement of plant growth and production recorded with the irradiated organic manure as compared to the unirradiated one. All parameters were higher in sweet pepper fertilized with poultry manure as compared to that fertilized with sheep manure. Although the treatment of organic manure only gave to some extent, less total yield, it has great impact on the

SEWAGE SLUDGE AS AN INGREDIENT IN FERTILIZERS AND SOIL SUBSTITUTES

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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.

Soil Fertility Status, Nutrient Uptake, and Maize (Zea mays L.) Yield Following Organic Matters and P Fertilizer Application on Andisol

Science.gov (United States)

Minardi, S.; Harieni, S.; Anasrullah, A.; Purwanto, H.

2017-04-01

Objective of this study were to elucidate effects of organic matters and P fertilizer application on soil fertility status, nutrient uptake and maize yield in the Andisol. This experiment consisted of two factors. The first factor comprised of four levels of organic matters input (without organic matter, manure, rice straw, and Gliricidia sepium leaves), with the application dosage 10 t.ha-1 and the second factor comprised of three levels of P fertilizer application (without P addition (control), 50 kg P2O5 ha-1, 100 kg P2O5 ha-1). Results of this study showed that organic matters and P fertilizer application improved soil fertility status, especially pH, soil organic C, cation exchange capacity (CEC), available P which resulted in an increase in P uptake that improve yield of maize. The highest yield of maize (corn cob) was obtained through application Gliricida sepium (8.40 t.ha-1), followed by manure (6.02 t.ha-1) and rice straw (5.87 t.ha-1). Application of 50 kg P2O5 Ha-1 yield was (5.76 t.ha-1) and application of 100 Kg P2O5 Ha-1 yield was (6.12 t.ha-1).

Impact of fertilization and granular insecticides on the incidence of tobacco aphid, myzus persicae (sulz)

International Nuclear Information System (INIS)

Razaq, A.; Hussain, N.; Khalil, S.K.; Alamzeb

1989-01-01

Field studies were conducted on the control of tobacco aphid, Myzus persicase (Sulz) with four granular insecticides, viz, Furadan 3% G, Diazinon 5% g, Thiodan 5% g and Larsban 5% g, with and without NPK fertilization. The aphid population was significantly higher in the fertilized plots compared to the non-fertilized ones. All the four insecticides significantly reduced the aphids density compared to the check. Furada 3% gave best results for the control of this pest. (author)

The Effect of Varying Speed Release of Nutrients from Fertilizers on Growth-production Process of Turf

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Peter Hric

2016-01-01

Full Text Available The aim of this experiment was to compare the influence of fertilizers with different speed of nutrients release on growth–production indicators of turf under non–irrigated conditions. The experiment was carried in warm and dry conditions in area Nitra (Slovak Republic. In the experiment were followed 5 treatments (1. without fertilization, 2. Nitre with dolomite, Superphosphate, Potassium salt, 3. Turf fertilizer Travcerit®, 4. Slow release fertilizer SRF NPK 14–5–14 (+ 4CaO + 4MgO + 7S, 5. Controlled release fertilizer Duslocote® NPK (S 13–9–18 (+6S. The highest gain of height reached variant fertilized by fertilizer SRF NPK 14–5–14 (+ 4CaO + 4MgO + 7S. Comparison of the individual treatments for the whole period showed significantly lower average daily gains of height on control treatment compared to fertilizing treatments Nitre with dolomite, Superphosphate, Potassium salt, SRF NPK 14–5–14 (+ 4CaO + 4MgO + 7S and Duslocote® NPK (S 13–9–18 (+6S. During the reported period the highest gain of weight reached treatment by application fertilizer Duslocote® NPK (S 13– 9–18 (+ 6S. Comparison of the individual treatments for the whole period, were found significantly lower average daily production of phytomass on control treatment in comparison with fertilization turfs by Travcerit® and Duslocote® NPK (S 13–9–18 (+6S.

Comparison of digestion methods to determine heavy metals in fertilizers

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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.

The effects of production water, WAF or CEWAF on the fertilization success of Atlantic cod eggs

International Nuclear Information System (INIS)

Burridge, L; Wong, D.; Trippel, E.

2010-01-01

Production water (PW), dispersed oil, and oil released from offshore oil and gas platforms can adversely affect fish populations. In this study, eggs from Atlantic cod were fertilized in the presence of PW collected from the Terra Nova and Hibernia offshore platforms in 2008. Cod eggs were also fertilized in the presence of the water accommodated fraction (WAF) and chemically enhanced water accommodated fraction (CEWAF) of Alaskan North Slope oil (ANS). Results of the study showed that exposure to the Terra Nova PW at 12 per cent (V/V) or higher resulted in significantly lower fertilization rates than those observed in controls. Exposure to Hibernia PW at 0.5 per cent (V/V) also resulted in significantly lower fertilization rates. The WAF of ANS up to 25 per cent (V/V) had no effect on fertilization rates. At 50 per cent (V/V), the fertilization rate for WAF ANS was much lower than rates observed in controls. The CEWAF significantly reduced fertilization at all tested concentrations.

Appraisal of pressmud and inorganic fertilizers on soil properties yield and sugarcane quality

International Nuclear Information System (INIS)

Sarwar, M.A.; Ibrahim, M.; Tahir, M.; Ahmad, K.; Khan, Z.I.; Valeem, E.E.

2010-01-01

A field experiment was conducted under semi-arid climatic conditions to evaluate the response of pressmud in combination with inorganic fertilizers and alone (only inorganic fertilizers) on the yield and sugarcane quality parameters besides a value-added product (locally called Gur). It is obvious from the results that inorganic fertilizer use (T2) has increased the tillers per plant, number of millable canes, stripped cane yield, sugar yield and juice present cane by 38.95 %, 38.66 %, 51.96 %, 54.92 % and 21.9 5% respectively, over the control (T1). Similarly when higher dose of pressmud was applied in integration with inorganic fertilizers (in T3), it increased total soluble solids, sucrose, purity, CSS and sugar recovery of juice by 7.83 %, 10.42 %, 2.80 %, 12.06 %, and 12.07 %, over the control (T1). The studies concluded that higher doses of mineral fertilizers increased gur % juice but it did not improve gur quality as done by higher doses of organic manures. Soil properties were also investigated before and after crop harvest. Maximum fertilizer use efficiency (124.29) was recorded in T2. (author)

Effect of music therapy on the anxiety levels and pregnancy rate of women undergoing in vitro fertilization-embryo transfer: A randomized controlled trial.

Science.gov (United States)

Aba, Yilda Arzu; Avci, Dilek; Guzel, Yilmaz; Ozcelik, Semanur Kumral; Gurtekin, Basak

2017-08-01

The aim of this study was to determine the effect of music therapy on the anxiety levels and pregnancy rates of women who underwent in vitro fertilization-embryo transfer. This prospective randomized controlled trial was conducted with 186 infertile women who presented to the In Vitro Fertilization Unit at the American Hospital in Turkey between April 2015 and April 2016. The infertile women who met the inclusion criteria were assigned to the music therapy group or the standard therapy group through block randomization. The study data were collected using the Personal Information Form, and State-Trait Anxiety Inventory. Early treatment success was determined by serum beta human chorionic gonadotrophin levels seven or ten days after the luteal day zero. For the analysis, descriptive statistics, chi-square test, Fisher's exact test, independent sample t-test were used. After the embryo transfer, the mean state anxiety scores decreased in both groups, and the mean trait anxiety score decreased in the music therapy group; however, the difference was not statistically significant (p>0.05). Clinical pregnancy rates did not differ between the music (48.3%) and standard (46.4%) therapy groups. After the two sessions of music therapy, state and trait anxiety levels decreased and pregnancy rates increased, but the difference was not significant. Therefore, larger sample sizes and more sessions are needed to evaluate whether music therapy has an effect on clinical outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

Human performance interfaces in air traffic control.

Science.gov (United States)

Chang, Yu-Hern; Yeh, Chung-Hsing

2010-01-01

This paper examines how human performance factors in air traffic control (ATC) affect each other through their mutual interactions. The paper extends the conceptual SHEL model of ergonomics to describe the ATC system as human performance interfaces in which the air traffic controllers interact with other human performance factors including other controllers, software, hardware, environment, and organisation. New research hypotheses about the relationships between human performance interfaces of the system are developed and tested on data collected from air traffic controllers, using structural equation modelling. The research result suggests that organisation influences play a more significant role than individual differences or peer influences on how the controllers interact with the software, hardware, and environment of the ATC system. There are mutual influences between the controller-software, controller-hardware, controller-environment, and controller-organisation interfaces of the ATC system, with the exception of the controller-controller interface. Research findings of this study provide practical insights in managing human performance interfaces of the ATC system in the face of internal or external change, particularly in understanding its possible consequences in relation to the interactions between human performance factors.

Slow-release fertilizers and possibilities of their utilizing in nursery

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Petr Salaš

2004-01-01

Full Text Available Reserve, slow-release fertilizers (SRF enable to simplify the whole system of plant nutrition and fertilisation. Tabletted fertilizers of the Silvamix series represent a prospective product of Czech provenience. At our university, these fertilizers have been tested and used since the year 1991. Ornamental woody species grown in containers were investigated in two stages. Experiments with ornamental plants were established using one-year-old cuttings and seedlings of the following deciduous and evergreen woody species: Cotoneaster dammeri Skogholm, Berberis thunbergii, Potentilla fruticosa Snowflake, Ligustrum vulgare Atrovirens and Picea omorika. After planting into containers, fertilizers in the dose of 1 tablet (i.e. 10 g per litre of substrate were applied either to roots level or on the soil surface in the container. Silvamix in the dose of 5 g.l-1 was used as the tested fertilizer in the second stage. It was applied during the planting in the form of tablets and/or a powder. Control plants were fertilized in the course of growing season using a common agricultural fertilizer Cererit Z. The annual plants increments were measured. These experiments demonstrated a long-term optimum effect of this product on woody species and an equal quality and efficiency of its tabletted and powdered forms.

Control of civilian plutonium inventories using burning in a non-fertile fuel

Energy Technology Data Exchange (ETDEWEB)

Oversby, V.M. [Lawrence Livermore National Lab., CA (United States); McPheeters, C.C. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439-4837 (United States); Degueldre, C. [Paul Scherrer Institute, 5232 Villigen-PSI (Switzerland); Paratte, J.M. [Paul Scherrer Institute, 5232 Villigen-PSI (Switzerland)

1997-05-01

The increasing inventories of plutonium generated by commercial nuclear power production represent a potential source for proliferation of nuclear weapons. To address this threat we propose separating the plutonium from the other constituents of commercial reactor spent fuel and burning it in a non-fertile fuel based on a zirconium dioxide matrix. The separation can be performed by the Purex process currently in use, but we recommend development of a more compact separation technology that would produce less secondary waste than currently used technology and would allow for more stringent accounting of plutonium inventories. The non-fertile fuel is designed for use in conventional light water power reactors and does not require development of new reactor technology. (orig.).

Control of civilian plutonium inventories using burning in a non-fertile fuel

Science.gov (United States)

Oversby, V. M.; McPheeters, C. C.; Degueldre, C.; Paratte, J. M.

1997-05-01

The increasing inventories of plutonium generated by commercial nuclear power production represent a potential source for proliferation of nuclear weapons. To address this threat we propose separating the plutonium from the other constituents of commercial reactor spent fuel and burning it in a non-fertile fuel based on a zirconium dioxide matrix. The separation can be performed by the Purex process currently in use, but we recommend development of a more compact separation technology that would produce less secondary waste than currently used technology and would allow for more stringent accounting of plutonium inventories. The non-fertile fuel is designed for use in conventional light water power reactors and does not require development of new reactor technology.

General aspects of fertility and infertility.

Science.gov (United States)

Damario, Mark A

2014-01-01

Fertility rates have been declining in most Western nations over the past several decades, although it is not entirely clear if an increased rate of infertility substantially contributes to this. As compared to other species, the reproductive efficiency of humans is relatively low. Factors related to fertility include age, exposure to sexually transmitted diseases, frequency of intercourse, coital timing, as well as diet and lifestyle habits. Infertility is considered a disease due to its major disruption of major organ systems and life functions. An infertility evaluation is recommended after 12 months or more of regular, unprotected intercourse and may be considered after 6 months for those female patients over the age of 35 or with other known abnormalities. A proper infertility evaluation is a comprehensive examination of possibly identifiable infertility factors of both female and male partners, lending itself to the most appropriate and potentially effective treatment.

Controlled release fertilizer increased phytoremediation of petroleum-contaminated sandy soil.

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Cartmill, Andrew D; Cartmill, Donita L; Alarcón, Alejandro

2014-01-01

A greenhouse experiment was conducted to determine the effect of the application of controlled release fertilizer [(CRF) 0, 4,6, or 8 kg m(-3)] on Lolium multiflorum Lam. survival and potential biodegradation of petroleum hydrocarbons (0, 3000, 6000, or 15000 mg kg(-1)) in sandy soil. Plant adaptation, growth, photosynthesis, total chlorophyll, and proline content as well as rhizosphere microbial population (culturable heterotrophic fungal and bacterial populations) and total petroleum hydrocarbon (TPH)-degradation were determined. Petroleum induced-toxicity resulted in reduced plant growth, photosynthesis, and nutrient status. Plant adaptation, growth, photosynthesis, and chlorophyll content were enhanced by the application of CRF in contaminated soil. Proline content showed limited use as a physiological indicator of petroleum induced-stress in plants. Bacterial and filamentous fungi populations were stimulated by the petroleum concentrations. Bacterial populations were stimulated by CRF application. At low petroleum contamination, CRF did not enhance TPH-degradation. However, petroleum degradation in the rhizosphere was enhanced by the application of medium rates of CRF, especially when plants were exposed to intermediate and high petroleum contamination. Application of CRF allowed plants to overcome the growth impairment induced by the presence of petroleum hydrocarbons in soils.

Fertilization Changes Chemical Defense in Needles of Mature Norway Spruce (Picea abies

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Line Nybakken

2018-06-01

Full Text Available Nitrogen availability limits growth in most boreal forests. However, parts of the boreal zone receive significant levels of nitrogen deposition. At the same time, forests are fertilized to increase volume growth and carbon sequestration. No matter the source, increasing nitrogen in the boreal forest ecosystem will influence the resource situation for its primary producers, the plants, with possible implications for their defensive chemistry. In general, fertilization reduces phenolic compound concentrations in trees, but existing evidence mainly comes from studies on young plants. Given the role of the phenolic compounds in protection against herbivores and other forest pests, it is important to know if phenolics are reduced with fertilization also in mature trees. The evergreen Norway spruce is long-lived, and it is reasonable that defensive strategies could change from the juvenile to the reproductive and mature phases. In addition, as the needles are kept for several years, defense could also change with needle age. We sampled current and previous year needles from an N fertilization experiment in a Norway spruce forest landscape in south-central Norway to which N had been added annually for 13 years. We analyzed total nitrogen (N and carbon (C, as well as low-molecular phenolics and condensed tannins. Needles from fertilized trees had higher N than those from controls plots, and fertilization decreased concentrations of many flavonoids, as well as condensed tannins in current year needles. In previous year needles, some stilbenes and condensed tannins were higher in fertilized trees. In control trees, the total phenolic concentration was almost five times as high in previous year needles compared with those from the current year, and there were great compositional differences. Previous year needles contained highest concentrations of acetophenone and stilbenes, while in the current year needles the flavonoids, and especially coumaroyl

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)

Effects of Nitrogen Fertilizers on the Growth and Nitrate Content of Lettuce (Lactuca sativa L.)

Science.gov (United States)

Liu, Cheng-Wei; Sung, Yu; Chen, Bo-Ching; Lai, Hung-Yu

2014-01-01

Nitrogen is an essential element for plant growth and development; however, due to environmental pollution, high nitrate concentrations accumulate in the edible parts of these leafy vegetables, particularly if excessive nitrogen fertilizer has been applied. Consuming these crops can harm human health; thus, developing a suitable strategy for the agricultural application of nitrogen fertilizer is important. Organic, inorganic, and liquid fertilizers were utilized in this study to investigate their effect on nitrate concentrations and lettuce growth. The results of this pot experiment show that the total nitrogen concentration in soil and the nitrate concentration in lettuce increased as the amount of nitrogen fertilizer increased. If the recommended amount of inorganic fertilizer (200 kg·N·ha−1) is used as a standard of comparison, lettuce augmented with organic fertilizers (200 kg·N·ha−1) have significantly longer and wider leaves, higher shoot, and lower concentrations of nitrate. PMID:24758896

Estimating Post-Emergency Fertility Among Disaster-Affected Adolescents: Findings From a Case-Control Study in Aceh Province, Indonesia.

Science.gov (United States)

Kinoshita, Mari; Suhardan, Suhardan; Danila Danila, Damsyik; Chiang, Chifa; Aoyama, Atsuko

2016-02-01

We aimed to retrospectively estimate adolescent fertility rates before and after a large-scale natural disaster. A case-control study was conducted in Aceh Province, Indonesia, 2 years after the Indian Ocean tsunami in 2004. The age-specific fertility rates of 15-19-year-old-women (ASFR 15-19) was estimated each year from 2004 to 2006 by creating hypothetical age cohorts. The results were compared with data from the closest edition of the Indonesian Demographic Health Survey (IDHS). The pre-disaster ASFR 15-19 (4.4% in 2004) was not significantly different from the 2002-2003 IDHS data (P=0.49), whereas the post-disaster ASFR 15-19 (1.1% in 2005-2006) was significantly lower than the provincial estimation in the 2007 IDHS (Pfertility estimation, however, we suggest excluding data from the 40-week period preceding the disaster, because the data may be biased by excess mortality in childbearing mothers and newborn babies in the disaster.

Fertilizer Reduction Policies in Developed Countries: Suitability and Implications

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LI Fang

2017-01-01

Full Text Available This study reviewed and analyzed the specific practices, implementation effects and applicable conditions of fertilizer reduction policies in the EU, US and Japan, explored the common laws and general conditions in the formulation of environmental orientation, and pro vided feasible policy recommendations for the formulation of fertilizer reduction policies in China. This study showed that fertilizer reduction policies in each country had their own advantages and disadvantages, and the applicable conditions were different. The EU's command and control policy was applicable to the situation of less farm households and the same agricultural planting type or farm type. The economic in centive policy in the US was applicable to the situation of more farm households, relatively perfect agricultural market system and sensitive price formation mechanism, while the public participation policy in Japan was applicable to regions with more relevant agricultural groups and strong economy. China should learn from each of these policies and make a comprehensive choice in the formulation of fertilizer reduc tion policies. Therefore, China should proceed from improving the agricultural price mechanism and the pollution-free agricultural products certification system as well as encouraging and supporting the development of large scale production units, and then promote the adoption of environmentally friendly technology through the guidance of market mechanism, ensure the effective implementation of environmental stan dards through farmers' integration and improve farmers' environmental awareness through propaganda guidance, so as to ensure the effective implementation of different types(command and control policy, economic incentive policy and public participation policyof fertilizer reduc tion policies.

HOMEMADE SLOW-ACTION FERTILIZERS, AS AN ECONOMIC SOLUTION FOR ORGANIC FOOD PRODUCTION

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Tomasz Ciesielczuk

2017-03-01

Full Text Available Organic plant cultivation, especially those intended for human consumption, poses new requirements for gardening. It is recommended to use organic slow-action fertilizers, which provide doses of nutrients essential for plants for a long time. Particularly valuable fertilizers are those that arise within the household, due to their high quality and the absence of costs associated with their purchase and transport. Organic matter contained in the food industry waste or arising in households, in the absence of contamination by other types of waste, can be used for self-production of organic fertilizer. The paper presents the results of testing organic fertilizers, which you can make yourself, destined for the cereal plants. The experimental fertilizers were made from coffee spent grounds (CSG and ash from the thermal conversion of biomass (A, and the components limiting the amount of pests in the form of leaves and flowers of tansy (Tanacetum vulgare L.. The fertilizer can be used at the time of planting and sowing, because of the slow release of nutrients. Moreover, the addition of leaves and flowers of tansy helps to protect the seedling due to the content of essential oils. As a comparison, the horse manure and rabbit droppings fertilizers were used. Such fertilizers can be prepared independently, which leads not only to reducing the weight of biodegradable and mineral waste, but also provides the ability to generate financial savings of the household and promote organic gardening. Fertilizers made from a mixture of CSG and A support the implementation of good agricultural practice and sustainable development.

Manipulation of Contents of Nitrate, Phenolic Acids, Chlorophylls, and Carotenoids in Lettuce (Lactuca sativa L.) via Contrasting Responses to Nitrogen Fertilizer When Grown in a Controlled Environment.

Science.gov (United States)

Qadir, Othman; Siervo, Mario; Seal, Chris J; Brandt, Kirsten

2017-11-22

This study aimed to use different nitrogen fertilizer regimes to produce Butterhead lettuce with such large differences in nitrate content that they could be used as treatment and placebo to study the effect of inorganic nitrate on human health. Plants were grown under controlled conditions at 27/23 °C day/night with a relatively low photosynthetically active radiation (PAR) of 150 μmol m -2 s -1 for 14 h day -1 and nitrogen supplies ranging from 26 to 154 ppm of N as ammonium nitrate in the fertigation solution. This resulted in contrasting high (∼1078 mg nitrate 100 g -1 FW) or low (∼6 mg 100 g -1 ) nitrate contents in the leaves. Contents of carotenoids and chlorophylls in fresh weight did not differ significantly between the highest and the lowest N-supply levels. However, increased nitrogen supply reduced contents of phenolic compounds from 154 to 22 mg 100 g -1 FW, dry matter content from 8.9% to 4.6%, and fresh weight per plant from 108.52 to 47.57 g/plant FW (all P < 0.001). Thus, while fertilizer treatments can provide lettuce with substantially different nitrate contents, maintaining similar pigment contents (color), they also strongly influence the contents of phenolic acids and flavones.

Manipulation of the fertility of marsupials for conservation of endangered species and control of over-abundant populations.

Science.gov (United States)

Mate, K E; Molinia, F C; Rodger, J C

1998-10-01

Marsupials present a dichotomy in population management; the numbers of many Australian marsupial species have declined due to loss of habitat, competition from introduced herbivores and predation by introduced carnivores, but other species have become locally overabundant in Australia or are introduced pests in New Zealand. The manipulation of reproduction offers the means to increase or decrease productivity; however, considerable fundamental research is required before reproductive technologies can be applied to marsupials. Marsupials differ from eutherian mammals in several aspects of their reproduction including sex differentiation, gamete function and endocrinology, as well as in the relative lengths of gestation and lactation. Although these differences present unique problems in the application of reproductive technologies to marsupials, they also present unique opportunities for marsupial-specific fertility control. This paper summarises the assisted breeding technologies currently being applied to marsupials including superovulation, artificial insemination, in vitro fertilization and gene banking; unique marsupial targets for contraceptive intervention including gamete production, sperm capacitation, gamete surface antigens and embryonic development; and some options for the delivery of contraceptive vaccines to marsupial populations.

[An attempt to explain fertility differentials in Upper Volta and in Ghana].

Science.gov (United States)

Coulibaly, S P; Pool, I

1975-01-01

This study examines fertility differentials in Western Africa, notably in Upper Volta and in Ghana. The relationship between social and cultural transformation and fertility rate is usually seen as a matter of cause and effect. Direct variables caused by social transformation would be education, migration, and urbanization. This is not necessarily so, at least according to the Davis-Blake paradigm, which says that there are intermediate variables which intervene between fertility rate and the social system. For West Africa such variables are of 3 distinct types: 1) those which upset the normal flow of the family, such as separation due to migration, divorce, and marriage age; 2) those which influence conception itself, such as birth control, lactation and sexual abstinence; and, 3) cultural factors, such as poligamy and monogamy, type of conjugal union, and postpartum sexual abstinence. The central point of this study is that direct variables, i.e. migration, education and urbanization, do not directly influence fertility, but they influence the so-called intermediate variables, which, in turn, cause a change in fertility patterns. It must be remembered that birth control is still practically unknown in Western Africa.

Fertility in midlife women.

Science.gov (United States)

Yoldemir, T

2016-06-01

Reduced maternal fertility is the consequence of depletion of follicles with maternal aging. In a 35-year-old woman, approximately 9.1% of the residual follicle pool disappears annually without entering into the growing stage, whereas, in a 45-year-old woman, this number triples. After the age of 35 years, the frequency of aneuploidies in oocytes increases sharply. Roughly 50-70% of mature oocytes from a 40-year-old woman have chromosomal abnormalities. The clinical pregnancy and implantation rates are lower in midlife women. Various controlled ovarian stimulation interventions have been suggested for the management of women in advanced age, most of whom are likely to be poor-responder patients. Currently, systematic reviews and meta-analyses suggest that there is insufficient evidence to recommend most of the treatments proposed to improve pregnancy rates in these poor responders. Minimal stimulation or natural cycle in vitro fertilization may be offered, without compromising the already existing pregnancy results.

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.

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.

Fertility Reactions to the "Great Recession" in Europe: Recent Evidence from Order-Specific Data

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Joshua Goldstein

2013-07-01

Full Text Available OBJECTIVE This paper provides recent cross-national evidence of the impact of the great recession on fertility in Europe in the context of the recent decade. METHODS Using data from the Human Fertility Database (HFD, from Eurostat, and from the OECD database, we employ fixed-effects modeling to study how changes in unemployment rates have affected birth rates across Europe. RESULTS We find that countries that were hit hard by the recession show reduced fertility when compared with a continuation of recent trends, especially at younger ages. CONCLUSIONS Our results indicate a strong relationship between economic conditions and fertility. However, there is variation by region, age, and parity suggesting the importance of life course and institutional factors.

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)

Effect of melatonin on maturation capacity and fertilization of Nili-Ravi buffalo (Bubalus bubalis oocytes

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G. Nagina

2016-08-01

Full Text Available This study evaluated the effect of melatonin supplementation of in vitro maturation media on in vitro maturation (IVM and in vitro fertilization (IVF rate of buffalo oocytes. Cumulus oocytes complexes (COCs were aspirated from follicles of 2-8 mm diameter. In experiment I, COCs were matured in IVM medium supplemented with 0 (control, 250, 500, and 1000 μM melatonin for 22-24 hours in CO2 incubator at 38.5°C with 5% CO2 and at 95% relative humidity. The maturation rate did not differ in media supplemented with melatonin at 250 μM, 500 μM, 1000 μM and control (0 μM. In experiment II, the matured oocytes were fertilized in 50 μl droplets of Tyrode’s Albumin Lactate Pyruvate (TALP medium having 10 ug/ml heparin for sperm (2 million/ml capacitation. The fertilization droplets were then kept for incubation at 5% CO2, 39°C and at 95% relative humidity for 18 hours. The fertilization rate was assessed by sperm penetration and pronuclear formation. Fertilization rate was improved when maturation medium was supplemented with 250 μM melatonin compared to control. In conclusion, melatonin supplementation to serum free maturation media at 250 μM improved the fertilization rate of buffalo oocytes.

Cadmium and zinc uptake by vegetable tissues after nine annual applications of phosphate fertilizer to soil

International Nuclear Information System (INIS)

Mortvedt, J.J.

1984-01-01

Plant uptake of heavy metals such as Cd and Zn applied to soil as contaminants in P fertilizers is of concern because of their possible entry into the human food chain. Concentrations in P fertilizers generally range from 1 to 50 mg kg/sup -1/ of Cd and 50 to 500 mg kg/sup -1/ of Zn, but much higher concentrations have been reported. Such wide ranges are due to variations in heavy metal contents of phosphate rock (PR) used to produce P fertilizers. Samples of vegetable tissues grown in New York on soil fertilized with triple superphosphate (TSP) for nine years of a 10-year experiment were analyzed for Cd and Zn. Results of this study show that plant availability of Cd and Zn contaminants in P fertilizers is rather low, even at high rates of P fertilization

Fertility trends and prospects in East and South-East Asian countries and implications for policies and programmes.

Science.gov (United States)

Leete, R

1991-01-01

Fertility trends and prospects for east and southeast Asian countries including cities in China, Taiwan, the Republic of Korea, Thailand, Indonesia, Malaysia, the Philippines, Myanmar, and Viet Nam are described. Additional discussion focuses on family planning methods, marriage patterns, fertility prospects, theories of fertility change, and policy implications for the labor supply, labor migrants, increased female participation in the labor force (LFP), human resource development, and social policy measures. Figures provide graphic descriptions of total fertility rates (TFRS) for 12 countries/areas for selected years between 1960-90, TFR for selected Chinese cities between 1955-90, the % of currently married women 15-44 years using contraception by main method for selected years and for 10 countries, actual and projected TFR and annual growth rates between 1990-2020 for Korea and Indonesia. It is noted that the 1st southeast Asian country to experience a revolution in reproductive behavior was Japan with below replacement level fertility by 1960. This was accomplished by massive postponement in age at marriage and rapid reduction in marital fertility. Fertility was controlled primarily through abortion. Thereafter every southeast Asian country experienced fertility declines. Hong Kong, Penang, Shanghai, Singapore, and Taipei and declining fertility before the major thrust of family planning (FP). Chinese fertility declines were reflected in the 1970s to the early 1980s and paralleled the longer, later, fewer campaign and policy which set ambitious targets which were strictly enforced at all levels of administration. Korea and Taiwan's declines were a result of individual decision making to restrict fertility which was encouraged by private and government programs to provide FP information and subsidized services. The context was social and economic change. Indonesia's almost replacement level fertility was achieved dramatically through the 1970s and 1980s by

Effects of treatment on fertility in long-term survivors of childhood or adolescent cancer

International Nuclear Information System (INIS)

Byrne, J.; Mulvihill, J.J.; Myers, M.H.

1987-01-01

In a retrospective cohort study of survivors of cancer and of controls, we estimated the risk of infertility after treatment for cancer during childhood or adolescence. We interviewed 2283 long-term survivors of childhood or adolescent cancer diagnosed in the period from 1945 through 1975, who were identified at five cancer centers in the United States. Requirements for admission to the study were diagnosis before the age of 20, survival for at least five years, and attainment of the age of 21. In addition, 3270 controls selected from among the survivors' siblings were interviewed. Cox regression analysis showed that cancer survivors who married and were presumed to be at risk of pregnancy were less likely than their sibling controls to have ever begun a pregnancy (relative fertility, 0.85; 95 percent confidence interval, 0.78 to 0.92). Radiation therapy directed below the diaphragm depressed fertility in both sexes by about 25 percent. Chemotherapy with alkylating agents, with or without radiation to sites below the diaphragm, was associated with a fertility deficit of about 60 percent in the men. Among the women, there was no apparent effect of alkylating-agent therapy administered alone (relative fertility, 1.02) and only a moderate fertility deficit when alkylating-agent therapy was combined with radiation below the diaphragm (relative fertility, 0.81). Relative fertility in the survivors varied considerably according to sex, site of cancer, and type of treatment; these factors should be taken into consideration in counseling survivors about the long-term consequences of disease

Infertile men's needs and asssessment of fertility care

DEFF Research Database (Denmark)

Sylvest, Randi; Fürbringer, Jeanette Krogh; Schmidt, Lone

2016-01-01

Introduction: Male infertility is potentially a severe, low-control stressor. There is limited knowledge of the expectations, needs, and assessment of fertility care among men with severe infertility. The aim of this study was to explore experience, expectations, needs, and assessment of fertility....... The men appreciated the staff’s kindness and professionalism but desired the staff to address emotional subjects too. Conclusion: The process from referral to treatment felt like a maze for these men. They needed the staff to give them the opportunity to speak of the psychosocial consequences of severe...

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.

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.)

interaction between phosphorus fertilizer and arbuscular ...

African Journals Online (AJOL)

userpc

examine the interaction between Phosphorus (P) fertilizer and Arbuscular Mycorrhizal Fungal ... recorded 28% and 4% total plant dry yield increment respectively over control. This study shows that ... ratio 1:3 inoculant: water, application per ... Table 1: Effect of P and AMF on the dry yield components of cassava (t ha-1).

Dairy intake in relation to in vitro fertilization outcomes among women from a fertility clinic.

Science.gov (United States)

Afeiche, M C; Chiu, Y-H; Gaskins, A J; Williams, P L; Souter, I; Wright, D L; Hauser, R; Chavarro, J E

2016-03-01

Is dairy food consumption associated with live birth among women undergoing infertility treatment? There was a positive association between total dairy food consumption and live birth among women ≥35 years of age. Dairy food intake has been previously related to infertility risk and measures of fertility potential but its relation to infertility treatment outcomes are unknown. Our study population comprised a total of 232 women undergoing 353 in vitro fertilization (IVF) treatment cycles between February 2007 and May 2013, from the Environment and Reproductive Health study, an ongoing prospective cohort. Diet was assessed before assisted reproductive technology (ART) treatment using a validated food frequency questionnaire. Study outcomes included ovarian stimulation outcomes (endometrial thickness, estradiol levels and oocyte yield), fertilization rates, embryo quality measures and clinical outcomes (implantation, clinical pregnancy and live birth rates). We used generalized linear mixed models with random intercepts to account for multiple ART cycles per woman while simultaneously adjusting for age, caloric intake, BMI, race, smoking status, infertility diagnosis, protocol type, alcohol intake and dietary patterns. The age- and calorie-adjusted difference in live birth between women in the highest (>3.0 servings/day) and lowest (Switzerland and completed this work while at the Harvard School of Public Health. The other authors declare no conflicts of interest. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Sexual function and fertility issues in cases of exstrophy epispadias complex

Directory of Open Access Journals (Sweden)

M S Ansari

2010-01-01

Full Text Available In patients with EEC, the issues such as sexuality, sexual function and fertility gain more importance once theses patients advance from puberty to adulthood. The aim of this review is to critically examine the available evidence on these issues. A systemic literature search was performed in Medline over the last 25 years using the key words: Exstrophy, sexual function and pregnancy. Search results were limited to studies of patients with exstrophy published in English literature. A total of 1500 publications were found and subsequently screened by title and when appropriate by abstracts. Of these, 40 publications pertinent to the subject were included for the analysis. The publications were supplemented by an additional 15 publications obtained from their bibliographies. The studies were rated according to the guidelines published by the US department of health and human services. Heterosexuality is usually expressed in both the sexes and most of them have adequate sexual function. Urinary diversion in some series seems to result in better ejaculatory hence fertility outcome in male patients. Recent series have shown equally good results with primary reconstruction. Most of the female patients have normal fertility while male patients have significantly low fertility. Most of the male and female patients with EEC have adequate sexual function. Most of the female patients have normal fertility while most of the male patients have significantly low fertility.

Microbiological Safety of Chicken Litter or Chicken Litter-Based Organic Fertilizers: A Review

Directory of Open Access Journals (Sweden)

Zhao Chen

2014-01-01

Full Text Available Chicken litter or chicken litter-based organic fertilizers are usually recycled into the soil to improve the structure and fertility of agricultural land. As an important source of nutrients for crop production, chicken litter may also contain a variety of human pathogens that can threaten humans who consume the contaminated food or water. Composting can inactivate pathogens while creating a soil amendment beneficial for application to arable agricultural land. Some foodborne pathogens may have the potential to survive for long periods of time in raw chicken litter or its composted products after land application, and a small population of pathogenic cells may even regrow to high levels when the conditions are favorable for growth. Thermal processing is a good choice for inactivating pathogens in chicken litter or chicken litter-based organic fertilizers prior to land application. However, some populations may become acclimatized to a hostile environment during build-up or composting and develop heat resistance through cross-protection during subsequent high temperature treatment. Therefore, this paper reviews currently available information on the microbiological safety of chicken litter or chicken litter-based organic fertilizers, and discusses about further research on developing novel and effective disinfection techniques, including physical, chemical, and biological treatments, as an alternative to current methods.

Effect of Radioactive and Toxic Metals Constituent in Fertilizers on Soil and Environment

International Nuclear Information System (INIS)

Quraishi, S.B.; Khan, M.M.K.; Akhter, S.

2007-01-01

Various types of fertilizers are being extensively used for crop production and other agricultural purposes in Bangladesh. Trace elements present in chemical and organic fertilizers could play an important role in crop production and human health. Eleven fertilizers samples were collected from local market and were analyzed for some heavy, essential and toxic elements like Fe,Cu, Co, Ni, Cr, Mn, Zn, Pb and Cd with Atomic absorption Spectrometer (AAS) and Al, Ba, Mo, and U with Inductively Coupled Plasma-Atomic Emission Spectrometer (ICP-AES). The fertilizers sampled contained below detection limit of Pb with the exception of TSP and Foly Boron (38.73 and 46.15 mg/kg). The concentration of Cd only in organic fertilizer was high (1621 mg/kg) among eleven samples. The levels of chromium in 50% of the samples were above the detection limit and organic fertilizer contents the highest amount of Cr (266.35 mg/kg). The level of uranium, which is an element of radioactive nature, was found to be below the detection limit (<50.00 mg/kg) in most of the cases with the excepton of TSP and organic fertilizer. To make a background data information, total flux of these elements into the cultivable soils was estimated from the analytical results obtained from this study.(author)

Why does fertility remain high among certain UK-born ethnic minority women?

Directory of Open Access Journals (Sweden)

Hill Kulu

2016-12-01

Full Text Available Background: Previous research has shown high total fertility among certain UK-born ethnic minorities, but the reasons behind their high fertility have remained far from clear. Some researchers attribute their elevated fertility levels to cultural factors, whereas others argue that high fertility is the consequence of their poor education and labour market prospects. Objective: This study investigates fertility among the descendants of immigrants in the UK and examines the determinants of high fertility among certain ethnic minority groups. Methods: We use data from the Understanding Society study and apply multivariate event history analysis. Results: The analysis shows, first, that relatively high second-, third-, and fourth-birth rates are responsible for the elevated total fertility among certain UK-born minorities, especially women of Pakistani and Bangladeshi origin. There is little variation in the first-birth rates among natives and immigrant descendants. Second, although fertility differences between ethnic minorities and native British women slightly decrease once religiosity and number of siblings are controlled for, significant differences persist. We conclude that cultural factors account for some elevated fertility among ethnic groups in the UK, whereas the role of education and employment seem to be only minor. Contribution: Cultural factors account for some elevated fertility among ethnic minorities in the UK, whereas the role of education and employment seem to be negligible.

A frozen-thawed in vitro-matured bovine oocyte derived calf with normal growth and fertility.

Science.gov (United States)

Otoi, T; Yamamoto, K; Koyama, N; Tachikawa, S; Suzuki, T

1996-08-01

The growth and fertility of a female calf obtained from a frozen-thawed bovine oocyte was assessed. The birth weight of the calf was lower than the mean birth weight of calves from in vitro fertilized embryos (IVF-controls) and calves obtained by artificial insemination (AI-controls). The growth rate of the calf up to 6 months was slower than that of the IVF-controls, but similar to that of the AI-controls. When the calf developed into a heifer (200 kg), she was inseminated with frozen semen and 280 days later delivered a male calf. The chromosoms of this cow were normal. These findings suggest that the growth and fertility of the calf derived from the frozen oocyte are normal.

Smoke, alcohol and drug addiction and male fertility.

Science.gov (United States)

Sansone, Andrea; Di Dato, Carla; de Angelis, Cristina; Menafra, Davide; Pozza, Carlotta; Pivonello, Rosario; Isidori, Andrea; Gianfrilli, Daniele

2018-01-15

In recent decades, the decline in human fertility has become increasingly more worrying: while therapeutic interventions might help, they are vexing for the couple and often burdened with high failure rates and costs. Prevention is the most successful approach to fertility disorders in males and females alike. We performed a literature review on three of the most common unhealthy habits - tobacco, alcohol and drug addiction - and their reported effects on male fertility. Tobacco smoking is remarkably common in most first-world countries; despite a progressive decline in the US, recent reports suggest a prevalence of more than 30% in subjects of reproductive age - a disturbing perspective, given the well-known ill-effects on reproductive and sexual function as well as general health. Alcohol consumption is often considered socially acceptable, but its negative effects on gonadal function have been consistently reported in the last 30 years. Several studies have reported a variety of negative effects on male fertility following drug abuse - a worrying phenomenon, as illicit drug consumption is on the rise, most notably in younger subjects. While evidence in these regards is still far from solid, mostly as a result of several confounding factors, it is safe to assume that cessation of tobacco smoking, alcohol consumption and recreational drug addiction might represent the best course of action for any couple trying to achieve pregnancy.

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.

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

Science.gov (United States)

Jalil, Wan Aznie Fatihah Wan Abd; Sharif, Shamshuritawati

2017-11-01

A fertility rate is a measure of the average number of children a woman will have during her childbearing years. Malaysia is now facing a population crisis and the fertility rate continues to decline. This situation will have implications for the age structure of the population where percentages of senior citizens are higher than percentages of people aged below 5 years old. Malaysia is expected to reach aging population status by the year 2035. As the aging population has a very long average life expectancy, the government needs to spend a lot on medical costs for senior citizens and need to increase budgets for pensions. The government may be required to increase tax revenues to support the growing older population. The falling fertility rate requires proper control by relevant authorities, especially through planning and implementation of strategic and effective measures. Hence, this paper aims to develop a fertility index using Shannon's entropy method. The results show that Selangor, Johor, and Sarawak are among the states with the highest values of the fertility index. On the other end of the spectrum, Terengganu, W.P. Labuan, and Perlis are ranked in the last positions according to the fertility index. The information generated from the results in this study can be used as a primary source for the government to design appropriate policies to mitigate dwindling fertility rates among Malaysian women.

Effect of Organic Fertilizers and Plant Density on Qualititative Characteristics of Balangu (Lallenamntia royleana Benth.

Directory of Open Access Journals (Sweden)

A Roohi Nogh

2017-10-01

Full Text Available Introduction Recently, the impact of chemical farming and the negative consequences on the environment and human health are on rise in Iran. Organic farming is gaining attention and increasing globally because it is eco-friendly, safe and has benefits for human health. The use of organic fertilizers in agriculture improves soil structure. Plant spacing and fertilizer applications have significant influence on the growth and yield in crop production. Optimum plant spacing ensures the proper use of land, as well as growth and nutrition in plants. Balangu (Lallemantia royleana Benth. is a medicinal plant from Lamiaceae family, containing essential oils and mucilage. The most important feature of this plant is the mucilage of the seeds. The seeds are a good source of fiber, oil and protein, and have medicinal and nutritional properties. Using the appropriate plant density and environmental friendly methods like organic fertilizers can improve the quality and quantity of medicinal plants production. Materials and Methods In order to study the effect of organic fertilizers and plant density on the qualitative characteristics of Balangu (Lallemantia royleana Benth. as a medicinal plant, an experiment was conducted at the Research Station of Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, during the growing season of 2011-2012. Soil samples were collected from the 15 cm depth of each experimental plots for laboratory analysis. This experiment was carried out as factorial layout based on randomized complete block design with three replications. Treatments were included five levels of fertilizer (cow manure, sheep manure, chicken manure, municipal solid waste compost and control and three levels of plant density (20, 30 and 40 plant m-2. The studied traits were included amount of mucilage, swelling factor, swelling per gram mucilage, mucilage and seed yield. Data were analyzed with SAS software. The F test was used to test the significance

Human spinal motor control

DEFF Research Database (Denmark)

Nielsen, Jens Bo

2016-01-01

Human studies in the past three decades have provided us with an emerging understanding of how cortical and spinal networks collaborate to ensure the vast repertoire of human behaviors. We differ from other animals in having direct cortical connections to spinal motoneurons, which bypass spinal...... the central motor command by opening or closing sensory feedback pathways. In the future, human studies of spinal motor control, in close collaboration with animal studies on the molecular biology of the spinal cord, will continue to document the neural basis for human behavior. Expected final online...

Specific antibodies to porcine zona pellucida detected by quantitative radioimmunoassay in both fertile and infertile women

International Nuclear Information System (INIS)

Kurachi, H.; Wakimoto, H.; Sakumoto, T.; Aono, T.; Kurachi, K.

1984-01-01

The specific radioimmunoassay system was developed for the titration of the antibodies to porcine zona pellucida (ZP) in human sera by using 125 I-labeled purified porcine ZP as antigen, which is known to have cross-reactivity with human ZP. The antibodies in human sera were detected in 3 of 11 (27%) women with unexplained infertility, in 16 of 48 (33%) amenorrheic patients, in 4 of 12 (33%) fertile women, and in 3 of 10 (30%) men. Moreover, antibody titers in infertile women were no higher than those in fertile women and in men. These results seem to suggest that the antibodies in human sera that cross-react with porcine ZP may not be an important factor in causing infertility in women

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.

Fertility targets and policy options in Asia.

Science.gov (United States)

Bulatao, R A

1984-11-01

The 3rd Asian and Pacific Population Conference in Colombo in 1982 recommended that countries review and modify existing demographic targets and goals for reducing birth and death rates in order to attain low levels as early as possible and to attain replacement level by the year 2000. The demographic goals of selected Asian countries (Bangladesh, Indonesia, Korea, Thailand, India, Pakistan, and the Philippines are assessed and compared to World Bank population projections. It also discusses the underlying rationale for setting fertility targets, and considers what government actions could make them more achievable. 6 stages for controlling population are distinguished: 1) collection and publication of reliable demographic data; 2) enunciation of an official policy to reduce population growth; 3) development of appropriate institutions to integrate demographic projections into economic plans; 4) promotion of family planning; 5) provision of incentives and disincentives, including elimination of all implicit and explicit subsidies for child bearing; and 6) restitution of birth quotas requiring permission for each child born. Principles to maintain and accelerate fertility declines to meet demographic targets include creating appropriate and equitable development policies, increasing the standard of family planning programs, confronting organizational problems, providing easier and more equal access to contraceptive methods, exploring innovative approaches to encourage smaller families and making a firm political commitment to population control. Rapid fertility decline will also require financial commitment. Willingness to spend the necessary amounts, and the capacity to spend them as well, will determine whether the countries of Asia enter the next century in control of their population.

Alternate partial root-zone irrigation improves fertilizer-N use efficiency in tomatoes

DEFF Research Database (Denmark)

Wang, Yaosheng; Liu, Fulai; Jensen, Lars Stoumann

2013-01-01

The objective of this study was to investigate the comparative effects of alternative partial root-zone irrigation (PRI) and deficit irrigation (DI) on fertilizer-N use efficiency in tomato plants under mineral N and organic N fertilizations. The plants were grown in split-root pots in a climate......-controlled glasshouse and were subjected to PRI and DI treatments during early fruiting stage. When analyzed across the N fertilizer treatments, PRI treatment led to significantly higher N yield, agronomic N use efficiency (ANUE), and apparent N recovery efficiency (ANRE) as compared with the DI treatment, indicating...... significantly higher fertilizer-N use efficiency and soil N availability as well as enhanced plant’s N acquisition ability in the PRI treatment. Analysis across the irrigation treatments showed that the mineral N fertilizer treatment (MinN) significantly increased N yield, ANUE and ANRE relative to the organic...

Oral administration of supplementary biotin differentially influences the fertility rate and oviductal expression of avidin and avidin-related protein-2 in low- and high-fertility broiler line hens.

Science.gov (United States)

Daryabari, H; Akhlaghi, A; Zamiri, M J; Pirsaraei, Z Ansari; Mianji, G Rahimi; Deldar, H; Eghbalian, A N

2015-02-01

Probable involvement of avidin and avidin-related protein-2 (AVR2) in sperm viability in the sperm storage tubules of turkeys has been suggested. The high affinity of biotin to avidin and its analogs is also well documented. The present study aimed to determine the effect of oral biotin on reproductive performance and oviductal mRNA expression of avidin and AVR2 in 2 broiler hen lines with different fertility rates. Low-fertility (line B) and high-fertility (line D) hens (n=144) were randomly allotted to receive 0 (T0), 0.30 (T1), or 0.45 (T2) mg/L biotin in drinking water from 30 through 33 wk of age. The reproductive performance of the hens was evaluated using artificial insemination. At the end of the treatment period, 24 hens per line were killed to assay the expression of avidin and AVR2 in the uterovaginal junction. Supplementary biotin increased egg production from 73.5% for T0 to 87.8% for T2. Hens administered with biotin in line B, but not in line D, showed an increase (8.4%) in fertility rate. Hatchability, chick quality, and overall embryonic mortality were not different among the experimental groups. Real-time PCR data showed that both avidin (P=0.0013) and AVR2 (Pbiotin×line interaction effect, where low-fertility line B hens receiving the high biotin level recorded respectively a 3.9 and 15.3% increase in avidin and AVR2 mRNA expression, although biotin did not affect these traits in line D hens. Control hens in line D had a dramatically higher AVR2 expression record (7.4-fold) compared with the control hens in line B. The correlation coefficients of fertility rate and avidin expression were 0.73 and 0.66 in lines B and D, respectively. However, the correlation of fertility and AVR2 (r=0.65) was significant for line D hens only. Overall, fertility rate and oviductal expression of avidin and AVR2 were dichotomously affected by oral biotin in low- and high-fertility line hens, where only low-fertility birds showed improvements in these attributes. �

The organic fertilizers in pepper (Capsicum annuum L. and the impact on yield and its components

Directory of Open Access Journals (Sweden)

Juan José Reyes Pérez

2017-10-01

Full Text Available The use of organic fertilizers in the fertilization of crops is an alternative to the problems generated by the intensive use of chemical fertilizers. The objective of this research was to evaluate the application to soil of organics fertilizers compared with a control treatment with chemical fertilization on the yield and its components in pepper (Capsicum annuum L.. Treatments consisted in to apply worm humus, water hyacinth compost, a mixture with 50 % worm humus and 50 % of water hyacinth compost, and a chemical control. It was evaluated fruits quantity per harvest, fruit length, diameter and fruit weight per harvest and yield. Results showed that the plants that were supplemented with worm humus, followed by worm humus + water hyacinth they had significantly better response with respect to the length, diameter and weight of the fruits.

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...

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

DEFF Research Database (Denmark)

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

2015-01-01

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

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.

Sex-linked strategies of human reproductive behavior.

Science.gov (United States)

Jaffe, K; Urribarri, D; Chacon, G C; Diaz, G; Torres, A; Herzog, G

1993-01-01

We present data on fertility characteristics in the Venezuelan population for each sex separately, allowing a detailed comparative analysis of the variance in fertility between males and females. We show that the fertility distribution for both sexes is discontinuous, that the average female has a larger number of offspring per individual than the average male, and that highly fertile males outnumber highly fertile females so that the total number of offspring produced by males and females is balanced. Results indicate that a few males are responsible for a relative higher fertility of the average female and that interactions between polyandric females with monogamic and polygynic males are common. Among the Yanomami, a relatively unacculturated hunter-gatherer-horticulturist tribe, similar differences in fertility distribution of both sexes are apparent. The data suggest that human populations contain statistically distinct subpopulations, with different reproductive strategies, suggesting the existence of complex interactions among human populations which are not evident from the study of individuals or groups.

Nitrous oxide emission from highland winter wheat field after long-term fertilization

Directory of Open Access Journals (Sweden)

X. R. Wei

2010-10-01

Full Text Available Nitrous oxide (N₂O is an important greenhouse gas. N₂O emissions from soils vary with fertilization and cropping practices. The response of N₂O emission to fertilization of agricultural soils plays an important role in global N₂O emission. The objective of this study was to assess the seasonal pattern of N₂O fluxes and the annual N₂O emissions from a rain-fed winter wheat (Triticum aestivum L. field in the Loess Plateau of China. A static flux chamber method was used to measure soil N₂O fluxes from 2006 to 2008. The study included 5 treatments with 3 replications in a randomized complete block design. Prior to initiating N₂O measurements the treatments had received the same fertilization for 22 years. The fertilizer treatments were unfertilized control (CK, manure (M, nitrogen (N, nitrogen + phosphorus (NP, and nitrogen + phosphorus + manure (NPM. Soil N₂O fluxes in the highland winter wheat field were highly variable temporally and thus were fertilization dependent. The highest fluxes occurred in the warmer and wetter seasons. Relative to CK, m slightly increased N₂O flux while N, NP and NPM treatments significantly increased N₂O fluxes. The fertilizer induced increase in N₂O flux occurred mainly in the first 30 days after fertilization. The increases were smaller in the relatively warm and dry year than in the cold and wet year. Combining phosphorous and/or manure with mineral N fertilizer partly offset the nitrogen fertilizer induced increase in N₂O flux. N₂O fluxes at the seedling stage were mainly controlled by nitrogen fertilization, while fluxes at other plant growth stages were influenced by plant and environmental conditions. The cumulative N₂O emissions were always higher in the fertilized treatments than in the non-fertilized treatment (CK. Mineral and manure

Education and Fertility: A comparative Micro-econometric Analysis in Europe

OpenAIRE

Luigi Aldieri; Concetto Paolo Vinci

2013-01-01

In this paper we investigate the relationship between education and completed fertility decisions at couple level for some EU countries. For this purpose we control for demographic, social and economic conditions, by using the European Community Household Panel (ECHP) dataset. In order to handle the endogeneity issue in fertility decisions, we use the Linear Generalized Method of Moments (GMM) method, where female’s education is instrumented by her partner’s education. The contribution to the...

Endometriosis and fertility: women's accounts of healthcare.

Science.gov (United States)

Young, K; Fisher, J; Kirkman, M

2016-03-01

reasons; there can be no 'one size fits all' approach to care. Women may benefit most from endometriosis care in which they are first asked about their fertility needs and preferences and in which medical uncertainty is acknowledged. K.Y. receives a scholarship from the National Health and Medical Research Council and Australian Rotary Health. J.F. is supported by a Monash Professional Fellowship and the Jean Hailes Professional Fellowship which is funded by Perpetual Trustees Pty Ltd. The authors have no conflicts of interest to declare. Not applicable. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Persistence of Trace Organic Contaminants from a Commercial Biosolids-Based Fertilizer in Aerobic Soils

OpenAIRE

Banet, Travis A; Kim, Jihyun R; Mashtare, Michael L

2016-01-01

Municipal biosolids are recycled as agricultural fertilizers. Recent studies have raised concerns due to the presence of emerging contaminants in municipal biosolids. Previous research suggests that these contaminants have the potential to reside in biosolids-based fertilizers that are commercially distributed. Use of these products in urban/suburban areas may provide a pathway for these contaminants to enter ecosystems and impact human and environmental health. Soils from Purdue University’s...

Balancing guava nutrition with liming and fertilization

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Amanda Hernandes

2012-12-01

Full Text Available Guava response to liming and fertilization can be monitored by tissue testing. Tissue nutrient signature is often diagnosed against nutrient concentration standards. However, this approach has been criticized for not considering nutrient interactions and to generate numerical biases as a result of data redundancy, scale dependency and non-normal distribution. Techniques of compositional data analysis can control those biases by balancing groups of nutrients, such as those involved in liming and fertilization. The sequentially arranged and orthonormal isometric log ratios (ilr or balances avoid numerical bias inherent to compositional data. The objectives were to relate tissue nutrient balances with the production of "Paluma" guava orchards differentially limed and fertilized, and to adjust the current patterns of nutrient balance with the range of more productive guava trees. It was conducted one experiment of 7-yr of liming and three experiments of 3-yr with N, P and K trials in 'Paluma' orchards on an Oxisol. Plant N, P, K, Ca and Mg were monitored yearly. It was selected the [N, P, K | Ca, Mg], [N, P | K], [N | P] and [Ca | Mg] balances to set apart the effects of liming (Ca-Mg and fertilizers (N-K on macronutrient balances. Liming largely influenced nutrient balances of guava in the Oxisol while fertilization was less influential. The large range of guava yields and nutrient balances allowed defining balance ranges and comparing them with the critical ranges of nutrient concentration values currently used in Brazil and combined into ilr coordinates.

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

Science.gov (United States)

Chen, Hong; Qu, Zaiqing; Liu, Wenhui

2017-04-01

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

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 ...

Frequency of depression among fertile and infertile women

International Nuclear Information System (INIS)

Qayyum, M.; Ahmed, S.; Kanwal, S.; Ishfaq, Y.; Hassan, H.; Waheed, N.

2014-01-01

To compare the frequency of depression among fertile and infertile women reporting in CMH Abbottabad. Study Design: A case control study. Place and Duration of Study: This study was conducted in Combined Military Hospital Abbottabad, over a period of six months from January 2013 to June 2013. Patients and Methods: The inclusion criteria were all those patients who were married. All the cases were selected from the women reporting in the obstetrics and gynecology department of CMH Abbottabad for investigation and treatment of infertility. A total of 200 patients, 100 fertile and 100 infertile women were included. Patients were given questionnaire form with their consent for research. Beck depression inventory (BDI) was used to assess depression among fertile and infertile women. Other factors such as age, educational level, and duration of infertility, pressure from family members, miscarriages, and support from husband were studied. Results: Depression was significantly higher in infertile women as compared to fertile women i.e. 95% vs. 63% (p < 0.001). It was higher among women with more than 1 year of duration of marriage as compared to those with infertility of one year duration or less. Conclusion: Infertility is associated with depression. (author)

Impact of religious faith & female literacy on fertility in a rural community of west Bengal

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Mandal N

2007-01-01

Full Text Available Background : Role of different social factors on fertility control is evident from different studies. What is the impact of religious faith and female literacy on fertility? Objectives : To study the role of religious faith and female literacy on fertility regulation in a rural community of West Bengal. Methods : Cross Sectional Study at rural field practice area of Department of Community Medicine, NRS Medical College, Kolkata, based on interview of married women in reproductive age group. A total of 671 filled in schedules were analyzed by Epi info package. Results : Average number of pregnancies ever occurred among Muslim mothers (2.8 were higher in comparison with Hindu mothers (1.68. Regarding current fertility, live births in last 2 yrs was more among Muslim mothers (25.2% as compared with their counterparts among Hindu community (12.4%. In both the cases differences were found to be statistically significant. Female literacy was found to have no impact on fertility as a whole, but while stratified, its positive role was evident among Hindu mothers but not among Muslim mothers. Conclusions : Factors, which have made differences in fertility between two religious groups, should be properly assessed and duly addressed for better fertility control in the community.

Safety Metrics for Human-Computer Controlled Systems

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Leveson, Nancy G; Hatanaka, Iwao

2000-01-01

The rapid growth of computer technology and innovation has played a significant role in the rise of computer automation of human tasks in modem production systems across all industries. Although the rationale for automation has been to eliminate "human error" or to relieve humans from manual repetitive tasks, various computer-related hazards and accidents have emerged as a direct result of increased system complexity attributed to computer automation. The risk assessment techniques utilized for electromechanical systems are not suitable for today's software-intensive systems or complex human-computer controlled systems.This thesis will propose a new systemic model-based framework for analyzing risk in safety-critical systems where both computers and humans are controlling safety-critical functions. A new systems accident model will be developed based upon modem systems theory and human cognitive processes to better characterize system accidents, the role of human operators, and the influence of software in its direct control of significant system functions Better risk assessments will then be achievable through the application of this new framework to complex human-computer controlled systems.

Effects of different fertilizers on growth and nutrient uptake of Lolium multiflorum grown in Cd-contaminated soils.

Science.gov (United States)

Liu, Mohan; Li, Yang; Che, Yeye; Deng, Shaojun; Xiao, Yan

2017-10-01

This study aimed to explore the effects of different fertilizers and their combinations on growth and nutrient and Cd uptake of Lolium multiflorum. Compared with control treatment, chemical fertilizer, organic manure, and their conjunctions with biofertilizer increased shoot biomass. Biofertilizers were found to cause significant reductions in shoot biomass of plants grown in organic manure-treated and control soil. Decreased soil-available N and P and shoot N and K concentrations in biofertilizer amendment treatments indicated that plant growth and nutrient absorption might be negatively affected under nutrient deficiency conditions. Elevated shoot biomasses contributed to the highest shoot Cd contents in chemical fertilizer and chemical fertilizer + biofertilizer treatments among all treatments. But the maximum translocation efficiency occurred in biofertilizer + chemical fertilizer + organic manure treatment, followed by organic manure and chemical fertilizer + organic manure treatments. Based on the results, we can conclude that the application of only the biofertilizer Bacillus subtilis should be avoided in nutrient-limited soils. Chemical fertilizer application could benefit the amount of Cd in shoots, and organic manure application and its combinations could result in the higher translocation efficiency.

Short-term fertilizer application alters phenotypic traits of symbiotic nitrogen fixing bacteria.

Science.gov (United States)

Simonsen, Anna K; Han, Shery; Rekret, Phil; Rentschler, Christine S; Heath, Katy D; Stinchcombe, John R

2015-01-01

Fertilizer application is a common anthropogenic alteration to terrestrial systems. Increased nutrient input can impact soil microbial diversity or function directly through altered soil environments, or indirectly through plant-microbe feedbacks, with potentially important effects on ecologically-important plant-associated mutualists. We investigated the impacts of plant fertilizer, containing all common macro and micronutrients on symbiotic nitrogen-fixing bacteria (rhizobia), a group of bacteria that are important for plant productivity and ecosystem function. We collected rhizobia nodule isolates from natural field soil that was treated with slow-release plant fertilizer over a single growing season and compared phenotypic traits related to free-living growth and host partner quality in these isolates to those of rhizobia from unfertilized soils. Through a series of single inoculation assays in controlled glasshouse conditions, we found that isolates from fertilized field soil provided legume hosts with higher mutualistic benefits. Through growth assays on media containing variable plant fertilizer concentrations, we found that plant fertilizer was generally beneficial for rhizobia growth. Rhizobia isolated from fertilized field soil had higher growth rates in the presence of plant fertilizer compared to isolates from unfertilized field soil, indicating that plant fertilizer application favoured rhizobia isolates with higher abilities to utilize fertilizer for free-living growth. We found a positive correlation between growth responses to fertilizer and mutualism benefits among isolates from fertilized field soil, demonstrating that variable plant fertilizer induces context-dependent genetic correlations, potentially changing the evolutionary trajectory of either trait through increased trait dependencies. Our study shows that short-term application is sufficient to alter the composition of rhizobia isolates in the population or community, either directly

Short-term fertilizer application alters phenotypic traits of symbiotic nitrogen fixing bacteria

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Anna K. Simonsen

2015-10-01

Full Text Available Fertilizer application is a common anthropogenic alteration to terrestrial systems. Increased nutrient input can impact soil microbial diversity or function directly through altered soil environments, or indirectly through plant-microbe feedbacks, with potentially important effects on ecologically-important plant-associated mutualists. We investigated the impacts of plant fertilizer, containing all common macro and micronutrients on symbiotic nitrogen-fixing bacteria (rhizobia, a group of bacteria that are important for plant productivity and ecosystem function. We collected rhizobia nodule isolates from natural field soil that was treated with slow-release plant fertilizer over a single growing season and compared phenotypic traits related to free-living growth and host partner quality in these isolates to those of rhizobia from unfertilized soils. Through a series of single inoculation assays in controlled glasshouse conditions, we found that isolates from fertilized field soil provided legume hosts with higher mutualistic benefits. Through growth assays on media containing variable plant fertilizer concentrations, we found that plant fertilizer was generally beneficial for rhizobia growth. Rhizobia isolated from fertilized field soil had higher growth rates in the presence of plant fertilizer compared to isolates from unfertilized field soil, indicating that plant fertilizer application favoured rhizobia isolates with higher abilities to utilize fertilizer for free-living growth. We found a positive correlation between growth responses to fertilizer and mutualism benefits among isolates from fertilized field soil, demonstrating that variable plant fertilizer induces context-dependent genetic correlations, potentially changing the evolutionary trajectory of either trait through increased trait dependencies. Our study shows that short-term application is sufficient to alter the composition of rhizobia isolates in the population or community

The Obesity-Fertility Protocol: a randomized controlled trial assessing clinical outcomes and costs of a transferable interdisciplinary lifestyle intervention, before and during pregnancy, in obese infertile women.

Science.gov (United States)

Duval, Karine; Langlois, Marie-France; Carranza-Mamane, Belina; Pesant, Marie-Hélène; Hivert, Marie-France; Poder, Thomas G; Lavoie, Hélène B; Ainmelk, Youssef; St-Cyr Tribble, Denise; Laredo, Sheila; Greenblatt, Ellen; Sagle, Margaret; Waddell, Guy; Belisle, Serge; Riverin, Daniel; Jean-Denis, Farrah; Belan, Matea; Baillargeon, Jean-Patrice

2015-01-01

Obesity in infertile women increases the costs of fertility treatments, reduces their effectiveness and increases significantly the risks of many complications of pregnancy and for the newborn. Studies suggest that even a modest loss of 5-10 % of body weight can restore ovulation. However, there are gaps in knowledge regarding the benefits and cost-effectiveness of a lifestyle modification program targeting obese infertile women and integrated into the fertility clinics. This study will evaluate clinical outcomes and costs of a transferable interdisciplinary lifestyle intervention, before and during pregnancy, in obese infertile women. We hypothesize that the intervention will: 1) improve fertility, efficacy of fertility treatments, and health of mothers and their children; and 2) reduce the cost per live birth, including costs of fertility treatments and pregnancy outcomes. Obese infertile women (age: 18-40 years; BMI ≥30 kg/m(2) or ≥27 kg/m(2) with polycystic ovary syndrome) will be randomised to either a lifestyle intervention followed by standard fertility treatments after 6 months if no conception has been achieved (intervention group) or standard fertility treatments only (control group). The intervention and/or follow-up will last for a maximum of 18 months or up to the end of pregnancy. Evaluation visits will be planned every 6 months where different outcome measures will be assessed. The primary outcome will be live-birth rates at 18 months. The secondary outcomes will be sub-divided into four categories: lifestyle and anthropometric, fertility, pregnancy complications, and neonatal outcomes. Outcomes and costs will be also compared to similar women seen in three fertility clinics across Canada. Qualitative data will also be collected from both professionals and obese infertile women. This study will generate new knowledge about the implementation, impacts and costs of a lifestyle management program in obese infertile women. This information

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

Science.gov (United States)

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…

Regulation of Mitochondrial Genome Inheritance by Autophagy and Ubiquitin-Proteasome System: Implications for Health, Fitness, and Fertility

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Won-Hee Song

2014-01-01

Full Text Available Mitochondria, the energy-generating organelles, play a role in numerous cellular functions including adenosine triphosphate (ATP production, cellular homeostasis, and apoptosis. Maternal inheritance of mitochondria and mitochondrial DNA (mtDNA is universally observed in humans and most animals. In general, high levels of mitochondrial heteroplasmy might contribute to a detrimental effect on fitness and disease resistance. Therefore, a disposal of the sperm-derived mitochondria inside fertilized oocytes assures normal preimplantation embryo development. Here we summarize the current research and knowledge concerning the role of autophagic pathway and ubiquitin-proteasome-dependent proteolysis in sperm mitophagy in mammals, including humans. Current data indicate that sperm mitophagy inside the fertilized oocyte could occur along multiple degradation routes converging on autophagic clearance of paternal mitochondria. The influence of assisted reproductive therapies (ART such as intracytoplasmic sperm injection (ICSI, mitochondrial replacement (MR, and assisted fertilization of oocytes from patients of advanced reproductive age on mitochondrial function, inheritance, and fitness and for the development and health of ART babies will be of particular interest to clinical audiences. Altogether, the study of sperm mitophagy after fertilization has implications in the timing of evolution and developmental and reproductive biology and in human health, fitness, and management of mitochondrial disease.

Impact of fertilizing with raw or anaerobically digested sewage sludge on the abundance of antibiotic-resistant coliforms, antibiotic resistance genes, and pathogenic bacteria in soil and on vegetables at harvest.

Science.gov (United States)

Rahube, Teddie O; Marti, Romain; Scott, Andrew; Tien, Yuan-Ching; Murray, Roger; Sabourin, Lyne; Zhang, Yun; Duenk, Peter; Lapen, David R; Topp, Edward

2014-11-01

The consumption of crops fertilized with human waste represents a potential route of exposure to antibiotic-resistant fecal bacteria. The present study evaluated the abundance of bacteria and antibiotic resistance genes by using both culture-dependent and molecular methods. Various vegetables (lettuce, carrots, radish, and tomatoes) were sown into field plots fertilized inorganically or with class B biosolids or untreated municipal sewage sludge and harvested when of marketable quality. Analysis of viable pathogenic bacteria or antibiotic-resistant coliform bacteria by plate counts did not reveal significant treatment effects of fertilization with class B biosolids or untreated sewage sludge on the vegetables. Numerous targeted genes associated with antibiotic resistance and mobile genetic elements were detected by PCR in soil and on vegetables at harvest from plots that received no organic amendment. However, in the season of application, vegetables harvested from plots treated with either material carried gene targets not detected in the absence of amendment. Several gene targets evaluated by using quantitative PCR (qPCR) were considerably more abundant on vegetables harvested from sewage sludge-treated plots than on vegetables from control plots in the season of application, whereas vegetables harvested the following year revealed no treatment effect. Overall, the results of the present study suggest that producing vegetable crops in ground fertilized with human waste without appropriate delay or pretreatment will result in an additional burden of antibiotic resistance genes on harvested crops. Managing human exposure to antibiotic resistance genes carried in human waste must be undertaken through judicious agricultural practice. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

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

Residual Effect Of Organic Fertilizer And Addition Inorganik Fertilizer To Nutrient Uptake Growth And Productions Of Black Soy Bean Glycine Max L. Merr At Rainfed Areas.

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Elli Afrida

2015-02-01

Full Text Available Abstract Research that have theme Residual Effect of Organic Fertilizer and Addition Anorganik Fertilizer to Nutrient Uptake Growth and pruductions of Black Soy Bean Glycine max L. Merr at Rainfed Wetland. Research was conducted at Suka Makmur village sub-distric Binjai Distric Langkat. Research was arranged in split plot design main plot is applications of phonska fertilizerwith 4 level i.e 0 t ha-1 A0 0.20 t ha-1 A1 0.25 t ha-1 A2 dan 0.30 t ha-1 A3 and sub plot is residual effect from first research with 16 combinations. Research was replicated 3 times. Result of research was showed application organic fertilizer that was combinated with anorganic fertilizer can increased N and K uptake. Application organic and anorganic fertilizer as single factor showed significantly effect of number of pods and soy bean productions but at interaction treatment not significantly effect however generally occurs increased production at O33A3 tratment until 80 comparison with control.

Contraceptive vaccines for the humane control of community cat populations

Science.gov (United States)

Levy, Julie K.

2011-01-01

Problem Free-roaming unowned stray and feral cats exist throughout the world, creating concerns regarding their welfare as well as their impact on the environment on public health. Millions of healthy cats are culled each year in an attempt to control their numbers. Surgical sterilization followed by return to the environment is an effective nonlethal population control method but is limited in scope due to expense and logistical impediments. Immunocontraception has the potential to be a more practical and cost-effective method of control. Method of study This is a review of current research in immunocontraception in domestic cats. Functional characteristics of an ideal immunocontraceptive for community cats would include a wide margin of safety for target animals and the environment, rapid onset and long duration of activity following a single treatment in males and females of all ages, and sex hormone inhibition. In addition, product characteristics should include stability and ease of use under field conditions, efficient manufacturing process, and low cost to the user. Two reproductive antigens, zona pellucida and GnRH, have been identified as possible targets for fertility control in cats. Results Zona pellucida, which is used successfully in multiple wildlife species, has achieved little success in cats. In contrast, immunization against GnRH has resulted in long-term contraception in both male and female cats following a single dose. GnRH is an ideal contraceptive target because it regulates pituitary and gonadal hormone responses in both males and females, thus suppressing nuisance behaviors associated with sex hormones in addition to preventing pregnancy. Conclusion The responsiveness of cats to fertility control via GnRH suppression should encourage researchers and cat control stakeholders to continue efforts to optimize vaccines that induce multi-year contraception following a single dose in a high proportion of treated cats. PMID:21501281

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.

Nitrogen fertilization of switchgrass increases biomass yield and improves net greenhouse gas balance in northern Michigan, U.S.A

International Nuclear Information System (INIS)

Nikiema, Paligwende; Rothstein, David E.; Min, Doo-Hong; Kapp, Christian J.

2011-01-01

Nitrogen (N) fertilization can increase bioenergy crop production; however, fertilizer production and application can contribute to greenhouse gas (GHG) emissions, potentially undermining the GHG benefits of bioenergy crops. The objective of this study was to evaluate the effects of N fertilization on GHG emissions and biomass production of switchgrass bioenergy crop, in northern Michigan. Nitrogen fertilization treatments included 0 kg ha -1 (control), 56 kg ha -1 (low) and 112 kg ha -1 (high) of N applied as urea. Soil fluxes of CO 2 , N 2 O and CH 4 were measured every two weeks using static chambers. Indirect GHG emissions associated with field activities, manufacturing and transport of fertilizer and pesticides were derived from the literature. Switchgrass aboveground biomass yield was evaluated at the end of the growing season. Nitrogen fertilization contributed little to soil GHG emissions; relative to the control, there were additional global warming potential of 0.7 Mg ha -1 y -1 and 1.5 Mg ha -1 y -1 as CO 2 equivalents (CO 2 eq), calculated using the IPCC values, in the low and high N fertilization treatments, respectively. However, N fertilization greatly stimulated CO 2 uptake by switchgrass, resulting in 1.5- and 2.5-fold increases in biomass yield in the low and high N fertilization treatments, respectively. Nitrogen amendments improved the net GHG benefits by 2.6 Mg ha -1 y -1 and 9.4 Mg ha -1 y -1 as CO 2 eq relative to the control. Results suggest that N fertilization of switchgrass in this region could reduce (15-50%) the land base needed for bioenergy production and decrease pressure on land for food and forage crop production. -- Highlights: → We examine the effects of N fertilization of switchgrass on GHG emissions. → Effects of N fertilization on biomass production of switchgrass bioenergy crop. → N fertilization contributed little to greenhouse gas emissions. → N fertilization greatly stimulated CO 2 uptake by the switchgrass. → N

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...

Serine proteinases and their inhibitors in fertilization

Czech Academy of Sciences Publication Activity Database

Jonáková, Věra; Jelínková-Slavíčková, Petra

2004-01-01

Roč. 8, 3,4 (2004), s. 108-110 ISSN 1211-8869. [Central European Conference on Human Tumor Markers /5./. Praha, 01.10.2004-03.10.2004] R&D Projects: GA ČR GA303/02/0433; GA ČR GP303/02/P069; GA ČR GP303/04/P070; GA MZd NJ7463 Institutional research plan: CEZ:AV0Z5052915 Keywords : serine proteinase * proteinase inhibitors * fertilization Subject RIV: CE - Biochemistry

Lifestyle factors and reproductive health: taking control of your fertility

OpenAIRE

Sharma, Rakesh; Biedenharn, Kelly R; Fedor, Jennifer M; Agarwal, Ashok

2013-01-01

Approximately 10 to 15% of couples are impacted by infertility. Recently, the pivotal role that lifestyle factors play in the development of infertility has generated a considerable amount of interest. Lifestyle factors are the modifiable habits and ways of life that can greatly influence overall health and well-being, including fertility. Many lifestyle factors such as the age at which to start a family, nutrition, weight, exercise, psychological stress, environmental and occupational exposu...

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

DEFF Research Database (Denmark)

Jensen, Allan; Sharif, Heidi; Frederiksen, Kirsten

2009-01-01

OBJECTIVE: To examine the effects of fertility drugs on overall risk of ovarian cancer using data from a large cohort of infertile women. DESIGN: Population based cohort study. SETTING: Danish hospitals and private fertility clinics. PARTICIPANTS: 54,362 women with infertility problems referred...... confounding factors. RESULTS: Analyses within cohort showed no overall increased risk of ovarian cancer after any use of gonadotrophins (rate ratio 0.83, 95% confidence interval 0.50 to 1.37), clomifene (1.14, 0.79 to 1.64), human chorionic gonadotrophin (0.89, 0.62 to 1.29), or gonadotrophin releasing...... hormone (0.80, 0.42 to 1.51). Furthermore, no associations were found between all four groups of fertility drugs and number of cycles of use, length of follow-up, or parity. CONCLUSION: No convincing association was found between use of fertility drugs and risk of ovarian cancer....

Use of selective serotonin reuptake inhibitors reduces fertility in men

DEFF Research Database (Denmark)

Nørr, L; Bennedsen, Birgit; Fedder, Jens

2016-01-01

Clinical review of the present data on the effects of selective serotonin reuptake inhibitors (SSRIs) on male fertility was the objective of the study. PubMed and Scopus were searched for publications in English or Danish and reviewed. Human trials, animal studies and in vitro studies were included...

Phosphate utilization by moong and cowpea under differential P fertility

International Nuclear Information System (INIS)

Thind, S.S.; Hundal, H.S.; Vig, A.C.

1993-01-01

A greenhouse experiment was conducted with 12 soils to study the effect of applied P on dry matter accumulation, P concentration, fertilizer and soil P uptake and utilization of P by moong and cowpea at two stages of growth. The magnitude of increase in yield due to applied P depended upon the native soil fertility. Low P fertility status soils registered proportionately higher increase in fertilizer P uptake. Dry matter yield of moong and cowpea significantly increased with increase in applied P in both the harvests, however in the first harvest (30 days growth stage) per cent increase with applied P over control was more in moong compared to cowpea. Soil P uptake increased significantly with applied P upto 60 kg P 2 O 5 /ha beyond which it decreased in both the harvests. The removal of P from applied and native sources was more in case of cowpea compared to moong. Per cent fertilizer P utilization in different soils varied from 45 to 11.9 in case of moong whereas its range in cowpea was 9.7 to 30.6 per cent. It decreased significantly with increase in applied P. (author). 7 refs., 1 fig., 3 tabs

Fertility and work-force participation: The experience of Melbourne Wives.

Science.gov (United States)

Ware, H

1976-11-01

Summary Current and retrospective data on the fertility control, work-force participation intentions and practice of Melbourne wives are combined in an examination of the causal link between work-force participation and reduced family size. Stress is laid on the analysis of the interaction between work-force participation and fertility over time, taking into account the proportion of married life spent in the work-force, rather than relying exclusively on a measure of current participation, the only option available in the analysis of census-type data. The wide range of information available makes it possible to study the effects of work-force participation on wives of unimpaired fertility, as well as the different consequences of planned and unplanned participation, and of working in a variety of occupations and for a number of distinct reasons. Examination of the future fertility intentions and current contraceptive practice of the younger wives shows that working wives are not, in these respects, markedly different from their house-wife peers. Overall, the balance of the evidence indicates that in the majority of cases fertility influences work-force participation rather than the converse.

Human factors methods for nuclear control room design. Volume I. Human factors enhancement of existing nuclear control rooms. Final report

International Nuclear Information System (INIS)

Seminara, J.L.; Seidenstein, S.; Eckert, S.K.; Smith, D.L.

1979-11-01

Human factors engineering is an interdisciplinary specialty concerned with influencing the design of equipment systems, facilities, and operational environments to promote safe, efficient, and reliable operator performance. Human factors approaches were applied in the design of representative nuclear power plant control panels. First, methods for upgrading existing operational control panels were examined. Then, based on detailed human factors analyses of operator information and control requirements, designs of reactor, feedwater, and turbine-generator control panels were developed to improve the operator-control board interface, thereby reducing the potential for operator errors. In addition to examining present-generation concepts, human factors aspects of advanced systems and of hybrid combinations of advanced and conventional designs were investigated. Special attention was given to warning system designs. Also, a survey was conducted among control board designers to (1) develop an overview of design practices in the industry, and (2) establish appropriate measures leading to a more systematic concern for human factors in control board design

Soil Fertility Status on Organic Paddy Experiment

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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.

Soil biological quality of grassland fertilized with adjusted cattle manure slurries in comparison with organic and inorganic fertilizers

NARCIS (Netherlands)

Eekeren, van N.J.M.; Boer, de Herman; Bloem, J.; Schouten, T.; Rutgers, M.; Goede, de R.G.M.; Brussaard, L.

2009-01-01

We studied the effect of five fertilizers (including two adjusted manure slurries) and an untreated control on soil biota and explored the effect on the ecosystem services they provided. Our results suggest that the available N (NO3- and NH4+) in the soil plays a central role in the effect of

Fertility behavior in rural and urban Indonesia.

Science.gov (United States)

Chernichovsky, D; Newlon, B; Sigit, H

1982-06-01

restraining effect on average fertility. Both traditional and modern sector jobs have a negative association with fertility. Those jobs which take a woman away from the home were the most forceful in their association with lower fertility. Also noticed was what might be an overriding direct effect of the government's family planning program on the compatibility of agricultural occupations with childbearing, through its promotion of birth control. When stratified, the data yield variations in urban and rural fertility behavior which speak of change occurring in the traditional rural society.

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...

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.

Human error mode identification for NPP main control room operations using soft controls

International Nuclear Information System (INIS)

Lee, Seung Jun; Kim, Jaewhan; Jang, Seung-Cheol

2011-01-01

The operation environment of main control rooms (MCRs) in modern nuclear power plants (NPPs) has considerably changed over the years. Advanced MCRs, which have been designed by adapting digital and computer technologies, have simpler interfaces using large display panels, computerized displays, soft controls, computerized procedure systems, and so on. The actions for the NPP operations are performed using soft controls in advanced MCRs. Soft controls have different features from conventional controls. Operators need to navigate the screens to find indicators and controls and manipulate controls using a mouse, touch screens, and so on. Due to these different interfaces, different human errors should be considered in the human reliability analysis (HRA) for advanced MCRs. In this work, human errors that could occur during operation executions using soft controls were analyzed. This work classified the human errors in soft controls into six types, and the reasons that affect the occurrence of the human errors were also analyzed. (author)

Application of different fertilizers on morphological traits of dill (Anethum graveolens L.).

Science.gov (United States)

Nejatzadeh-Barandozi, Fatemeh; Gholami-Borujeni, Fathollah

2014-12-01

The aim of this study was to evaluate the effects of nitroxin biofertilizer and chemical fertilizer on the growth, yield, and essential oil composition of dill. The experiment was conducted under field condition in randomized complete block design with three replications and two factors. The first factor was the concentrations of nitroxin biofertilizer (0%, 50%, and 100%) of the recommended amount (1 l of biological fertilizer for 30 kg of seed). The second factor was the following chemical fertilizer treatments: no fertilizer (control) and 50 and 100 kg ha(-1) urea along with 300 kg ha(-1) ammonium phosphate. Different characteristics such as plant height, number of umbel per plant, number of umbellet per umbel, number of grain per umbellet, 1,000 seed weight, grain yield, biological yield, and oil percentage were recorded. According to the results, the highest height, biological yield, and grain yield components (except harvest index) were obtained on biological fertilizer. The results showed the highest essential oil content detected in biological fertilizer and chemical fertilizer. Identification of essential oil composition showed that the content of carvone increased with the application of biofertilizers and chemical fertilizers. The results indicated that the application of biofertilizers enhanced yield and other plant criteria in this plant. Generally, it seems that the use of biofertilizers or combinations of biofertilizer and chemical fertilizer could improve dill performance in addition to reduction of environmental pollution.

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

Science.gov (United States)

Hacker, J. David

2016-01-01

This study relies on IPUMS samples of the 1850, 1860, 1870, and 1880 censuses, aggregate census data, and the timing of state laws criminalizing abortion to construct regional estimates of marital fertility in the United States and estimate correlates of marital fertility. The results show a significant lag between the onset of marital fertility decline in the nation’s northeastern census divisions and its onset in western and southern census divisions. Empirical models indicate the presence of cultural, economic, and legal impediments to the diffusion of marital fertility control and illustrate the need for more inclusive models of fertility decline. PMID:27757800

Online analysis of potassium fertilizers by Laser-Induced Breakdown Spectroscopy

International Nuclear Information System (INIS)

Groisman, Y.; Gaft, M.

2010-01-01

Presently, online analysis in potassium fertilizers industry is performed by Natural Radioactivity Analyzers. Laser Distance Spectrometry (LDS) has tested, by laboratory scale, the possibility of Laser-Induced Breakdown Spectroscopy (LIBS) technique implementation for online fertilizers production control. The main advantage of the system comparing to the existing technique is the principal possibility to analyze all relevant elements, such as K, Na, Mg, and not only K40 isotope as done in natural radiation analytical systems. Good correlations between online LIBS results with chemical analysis data of K, Na and Mg impurities of samples from Russia, Belarus and Israel demonstrate that LIBS system is a perspective tool for online control of those elements in field conditions.

The Trojan Female Technique: A Novel, Effective and Humane Approach for Pest Population Control

Energy Technology Data Exchange (ETDEWEB)

Gemmell, Neil J. [Centre for Reproduction and Genomics and Allan Wilson Centre for Molecular Ecology and Evolution, Department of Anatomy, University of Otago, Dunedin (New Zealand); Jalilzadeh, Aidin [Department of Mathematics and Statistics, University of Otago, Dunedin (New Zealand); Didham, Raphael K. [School of Animal Biology, University of Western Australia (Australia); CSIRO Ecosystem Sciences, Perth, Western Australia (Australia); Soboleva, Tanya [Science and Risk Assessment Directorate, Ministry for Primary Industries, PO Box 2526, Wellington (New Zealand); Tompkins, Daniel M. [Landcare Research, Private Bag 1930, Dunedin (New Zealand); New Zealand Institute for Plant and Food Research Ltd., Christchurch (New Zealand)

2014-01-15

Full-text: Humankind's ongoing battle with pest species spans millennia. Pests cause or carry disease, damage or consume food crops and other resources, and drive global environmental change. Conventional approaches to pest management usually involve lethal control, but such approaches are costly, of varying efficiency and often have ethical issues. Thus, pest management via control of reproductive output is increasingly considered an optimal solution. One of the most successful such 'fertility control' strategies developed to date is the sterile male technique (SMT), in which large numbers of sterile males are released into a population each generation. However, this approach is time-consuming, labour- intensive and costly. We use mathematical models to test a new twist on the SMT, using maternally inherited mitochondrial (mtDNA) mutations that affect male, but not female reproductive fitness. 'Trojan females' carrying such mutations, and their female descendants, produce 'sterile-male'-equivalents under natural conditions over multiple generations. We find that the Trojan Female Technique (TFT) has the potential to be a novel humane approach for pest control. Single large releases and relatively few small repeat releases of Trojan females both provided effective and persistent control within relatively few generations. Although greatest efficacy was predicted for high-turnover species, the additive nature of multiple releases made the TFT applicable to the full range of life histories modelled. The extensive conservation of mtDNA among eukaryotes suggests this approach could have broad utility for pest control. (author)

The Trojan female technique: a novel, effective and humane approach for pest population control.

Science.gov (United States)

Gemmell, Neil J; Jalilzadeh, Aidin; Didham, Raphael K; Soboleva, Tanya; Tompkins, Daniel M

2013-12-22

Humankind's ongoing battle with pest species spans millennia. Pests cause or carry disease, damage or consume food crops and other resources, and drive global environmental change. Conventional approaches to pest management usually involve lethal control, but such approaches are costly, of varying efficiency and often have ethical issues. Thus, pest management via control of reproductive output is increasingly considered an optimal solution. One of the most successful such 'fertility control' strategies developed to date is the sterile male technique (SMT), in which large numbers of sterile males are released into a population each generation. However, this approach is time-consuming, labour-intensive and costly. We use mathematical models to test a new twist on the SMT, using maternally inherited mitochondrial (mtDNA) mutations that affect male, but not female reproductive fitness. 'Trojan females' carrying such mutations, and their female descendants, produce 'sterile-male'-equivalents under natural conditions over multiple generations. We find that the Trojan female technique (TFT) has the potential to be a novel humane approach for pest control. Single large releases and relatively few small repeat releases of Trojan females both provided effective and persistent control within relatively few generations. Although greatest efficacy was predicted for high-turnover species, the additive nature of multiple releases made the TFT applicable to the full range of life histories modelled. The extensive conservation of mtDNA among eukaryotes suggests this approach could have broad utility for pest control.

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.

Effects of a certified organic fertilizer on the yield and market quality ...

African Journals Online (AJOL)

The researched fertilizer quantities were at the rates of 500, 1.000, 2.000 and 3.500 kg ha-1 and the control treatment was a plot where no organic fertilizer was applied. Field trials were conducted in the spring cycle of parsley growing, from 2005 to 2008, in Starcevo, on anthropogenic soil of subtype chernozem with signs of ...

Interrelation between human fertility and seminal plasma lipids, prostaglandins and zinc

International Nuclear Information System (INIS)

Hafiez, A.A.; Zaki, K.; Abbas, E.Z.; Halawa, F.A.; Abdel-Azis, A.

1986-01-01

In adult fertile men (32), men with oligospermia (43) and men with azoospermia (31) seminal plasma lipids, prostaglandins (PG) and Zn were determined. The PGs were determined by radioimmunoassay. In oligospermia the seminal plasma levels of PGE phospholipids, triglycerides and Zn were significantly increased, while the PGF/sub 2α/ level was unchanged. In azoospermia the seminal plasma total lipids, phospholipids and cholesterol were significantly decreased, PGE revealed an insignificant decrease only

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

Science.gov (United States)

Bay, Bjørn

2014-10-01

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

In vitro maturation, fertilization, embryo development & clinical outcome of human metaphase-I oocytes retrieved from stimulated intracytoplasmic sperm injection cycles

Directory of Open Access Journals (Sweden)

Cristina Álvarez

2013-01-01

Full Text Available Background & objectives: The major cause of fertilisation failure after ICSI is failure of the oocyte to initiate the biochemical processes necessary for activation. This inability could be ascribed to cytoplasmic immaturity of those gametes even if they had reached nuclear maturity. The activation of a mature oocyte is characterised by release from metaphase II (MII arrest and extrusion of the second polar body, followed by pro-nuclear formation. The aim of this study was to evaluate the fate of in vitro matured (IVM metaphase I (MI oocytes subjected to intracytoplasmic sperm injection (ICSI at different time intervals after extrusion of the first polar body (1PB in in vitro fertilization (IVF cycles. Methods: A total of 8030 oocytes were collected from 1400 ICSI cycles, 5504 MII at the time of cumulus retrieval. Four hundred eight metaphase II (MII (27.1% matured to MII after in vitro culture for 2-26 h and 5389 sibling MII in the moment of oocyte denudation were injected. On the other hand, 49 ICSI cycles containing only MI oocytes at retrieval were injected at three different time intervals after reaching the MII. The intervals were as follows: 2-6 h (n=10, 8-11 h (n=4 and 23-26 h (n=10. Fertilization and development potential were evaluated in both studies. Results: Fertilization, embryo cleavage and quality were significantly lower in IVM MI compared to MII at time of denudation. Pregnancy rate was higher in group MII. Pregnancy was achieved in three embryo transfers when ICSI was performed within 2-6 h (group I and 8-11 h (group II after PB extrusion. One pregnancy was obtained in group I and a healthy neonate was born. Interpretation & conclusions: Immature oocytes from women whose ovaries have been stimulated could be matured, fertilized by ICSI, cleaved in vitro and to give rise to a live birth. However, the developmental competence of embryos derived from immature oocytes is reduced, compared with sibling in vivo matured oocytes

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

Phosphorus fertilizer and grazing management effects on phosphorus in runoff from dairy pastures.

Science.gov (United States)

Dougherty, Warwick J; Nicholls, Paul J; Milham, Paul J; Havilah, Euie J; Lawrie, Roy A

2008-01-01

Fertilizer phosphorus (P) and grazing-related factors can influence runoff P concentrations from grazed pastures. To investigate these effects, we monitored the concentrations of P in surface runoff from grazed dairy pasture plots (50 x 25 m) treated with four fertilizer P rates (0, 20, 40, and 80 kg ha(-1) yr(-1)) for 3.5 yr at Camden, New South Wales. Total P concentrations in runoff were high (0.86-11.13 mg L(-1)) even from the control plot (average 1.94 mg L(-1)). Phosphorus fertilizer significantly (P pasture biomass (P dairy pastures should be the maintenance of soil P at or near the agronomic optimum by the use of appropriate rates of P fertilizer.