WorldWideScience

Sample records for human fertility control

  1. Is Wildlife Fertility Control Always Humane?

    Directory of Open Access Journals (Sweden)

    Jordan O. Hampton

    2015-10-01

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

  2. Is Wildlife Fertility Control Always Humane?

    Science.gov (United States)

    Hampton, Jordan O.; Hyndman, Timothy H.; Barnes, Anne; Collins, Teresa

    2015-01-01

    Simple Summary There are various fertility control methods (modalities) currently available that aim to reduce the abundance of problematic free-ranging mammalian wildlife. Here, we propose that dissimilarities in the mechanism of action indicate these methods produce great variation in animal welfare outcomes. We present a framework to assist managers in minimising animal welfare risks. Abstract Investigation of fertility control techniques to reduce reproductive rates in wildlife populations has been the source of much research. Techniques targeting wildlife fertility have been diverse. Most research into fertility control methods has focused upon efficacy, with few studies rigorously assessing animal welfare beyond opportunistic anecdote. However, fertility control techniques represent several very different mechanisms of action (modalities), each with their own different animal welfare risks. We provide a review of the mechanisms of action for fertility control methods, and consider the role of manipulation of reproductive hormones (“endocrine suppression”) for the long-term ability of animals to behave normally. We consider the potential welfare costs of animal manipulation techniques that are required to administer fertility treatments, including capture, restraint, surgery and drug delivery, and the requirement for repeated administration within the lifetime of an animal. We challenge the assumption that fertility control modalities generate similar and desirable animal welfare outcomes, and we argue that knowledge of reproductive physiology and behaviour should be more adeptly applied to wild animal management decisions. We encourage wildlife managers to carefully assess long-term behavioural risks, associated animal handling techniques, and the importance of positive welfare states when selecting fertility control methods as a means of population control. PMID:26506395

  3. The right to be born: surrogacy and the legal control of human fertility.

    Science.gov (United States)

    Lupton, M L

    1989-01-01

    South African law, in common with many other legal systems, has exercised a strong measure of control over the fertility of its citizens via the sanction of illegitimacy and the prohibition of marriage (and hence legitimate children) between certain persons, e.g. those who fall within the so-called prohibited degrees of relationship. Until last year, when the Mixed Marriages Act was abolished, marriage across the colour line was prohibited in South Africa. The requirement of a valid consent by both prospective spouses in order to enter into marriage further excludes certain categories of persons from procreating legitimate children, e.g. the insane and mentally feeble, while the requirement of consummation will exclude certain categories of paraplegics from solemnizing a valid marriage. Age restrictions on marriages and the requirement of parental consent for minors are further factors limiting the individual's freedom to procreate. These restrictions have a well-established historical basis extending over many hundreds of years. They can be broadly categorised as having as their objective the preservation of the family unit. The above provisions were formulated at a time when the law never contemplated the spectacular advances in human biology that have produced the numerous artificial forms of conception, such as AID, IVF and surrogacy. The legislature, both in South Africa and elsewhere, at first adopted a neutral approach to this new fertility revolution and watched the courts struggle to adapt outmoded principles to the new technology. Legislation relating to AID and IVF eventually appeared in many jurisdictions; as a result of its delayed introduction public opinion had been educated to accept the new techniques and the legislation is by and large favourable to these new techniques. Not so, however, as far as surrogacy is concerned. South Africa, England and Australia have produced essentially negative legislation on this subject. Certain American states

  4. Milder ovarian stimulation for in-vitro fertilization reduces aneuploidy in the human preimplantation embryo: A randomized controlled trial

    NARCIS (Netherlands)

    E.B. Baart (Esther); E. Martini (Elena); M.J.C. Eijkemans (René); D. van Opstal (Diane); N.G.M. Beckers (Nicole); A. Verhoeff (Arie); N.S. Macklon (Nick); B.C.J.M. Fauser (Bart)

    2007-01-01

    textabstractBACKGROUND: To test whether ovarian stimulation for in-vitro fertilization (IVF) affects oocyte quality and thus chromosome segregation behaviour during meiosis and early embryo development, preimplantation genetic screening of embryos was employed in a prospective, randomized controlled

  5. Human Capital, Fertility and Growth

    OpenAIRE

    Galor, Oded

    2006-01-01

    The demographic transition that swept the world in the past 140 years has been identified as one of the prime forces in the transition from stagnation to growth. The unprecedented increase in population growth during the early stages of industrialization was ultimately reversed. The rise in the demand for human capital in the second phase of industrialization brought about a significant reduction in fertility rates and population growth in various regions of the world, enabling economies to c...

  6. Air pollution and human fertility rates

    NARCIS (Netherlands)

    Nieuwenhuijsen, Mark J.; Basagaña, Xavier; Dadvand, Payam; Martinez, David; Cirach, Marta; Beelen, Rob; Jacquemin, Bénédicte

    2014-01-01

    Background: Some reports have suggested effects of air pollution on semen quality and success rates of in vitro fertilization (IVF) in humans and lower fertility rates in mice. However, no studies have evaluated the impact of air pollution on human fertility rates. Aims: We assessed the association

  7. Air pollution and human fertility rates

    NARCIS (Netherlands)

    Nieuwenhuijsen, Mark J.; Basagaña, Xavier; Dadvand, Payam; Martinez, David; Cirach, Marta; Beelen, Rob|info:eu-repo/dai/nl/30483100X; Jacquemin, Bénédicte

    2014-01-01

    Background: Some reports have suggested effects of air pollution on semen quality and success rates of in vitro fertilization (IVF) in humans and lower fertility rates in mice. However, no studies have evaluated the impact of air pollution on human fertility rates. Aims: We assessed the association

  8. A randomized control comparison study of culture media (HTF versus P1) for human in vitro fertilization.

    Science.gov (United States)

    Artini, Paolo G; Valentino, Valeria; Cela, Vito; Cristello, Francesca; Vitè, Alessandra; Genazzani, Andrea R

    2004-10-15

    It is now widely accepted that increasing the number of replacement embryos (>3 embryos per embryo transfer [ET]) is associated with an increased risk of multiple pregnancies. While embryo reduction is often proposed when there is a high risk of multiple pregnancies, it is a difficult decision for the couple. For this reason, different studies have focused on single embryo transfer, more precisely blastocyst transfer. The aim of the study is to confirm that phosphate-free culture media can be used to generate greater quality embryos. We carried out a study to compare the efficacy of human tubal fluid (HTF) versus preimplantation stage one (P1) as culture media for assisted reproductive therapy (ART). In 109 nonselected patients, we obtained an embryo fertilization rate with HTF and P1 culture media of 58.6 and 62.5% (P = 0.003), respectively. After 48 and 72 h, the morphology was similar for both P1 and HTF embryos in most patients. However, in the same patients, when HTF embryo quality was low (15.4%), P1 embryo quality was significantly higher 68.7% (P = 0.002). Some embryos were transferred at 48 h and some at 72 h after retrieval, in a randomized manner. We transferred a maximum of up to three embryos per ET. The implantation rate was significantly different; at 48 h, it was 6.8 and 12.2% for HTF and P1, respectively (P = 0.02). The pregnancy rate was 17.1% for HTF embryos and 23.7% for P1 embryos (P = 0.02). Therefore, we observed a significant difference between P1 and HTF in the fertilization rate, in embryo quality, in implantation rate and in pregnancy rate. But the most important difference between this study and others is that every patient was the control of herself, so we eliminated every variable.

  9. Milder ovarian stimulation for in-vitro fertilization reduces aneuploidy in the human preimplantation embryo : a randomized controlled trial

    NARCIS (Netherlands)

    Baart, Esther B.; Martini, Elena; Eijkemans, Marinus J.; Van Opstal, Diane; Beckers, Nicole G. M.; Verhoeff, Arie; Macklon, Nicolas S.; Fauser, Bart C. J. M.

    2007-01-01

    To test whether ovarian stimulation for in-vitro fertilization (IVF) affects oocyte quality and thus chromosome segregation behaviour during meiosis and early embryo development, preimplantation genetic screening of embryos was employed in a prospective, randomized controlled trial, comparing two ov

  10. Modelling and simulations of controlled release fertilizer

    Science.gov (United States)

    Irfan, Sayed Ameenuddin; Razali, Radzuan; Shaari, Ku Zilati Ku; Mansor, Nurlidia

    2016-11-01

    The recent advancement in controlled release fertilizer has provided an alternative solution to the conventional urea, controlled release fertilizer has a good plant nutrient uptake they are environment friendly. To have an optimum plant intake of nutrients from controlled release fertilizer it is very essential to understand the release characteristics. A mathematical model is developed to predict the release characteristics from polymer coated granule. Numerical simulations are performed by varying the parameters radius of granule, soil water content and soil porosity to study their effect on fertilizer release. Understanding these parameters helps in the better design and improve the efficiency of controlled release fertilizer.

  11. Air pollution and human fertility rates.

    Science.gov (United States)

    Nieuwenhuijsen, Mark J; Basagaña, Xavier; Dadvand, Payam; Martinez, David; Cirach, Marta; Beelen, Rob; Jacquemin, Bénédicte

    2014-09-01

    Some reports have suggested effects of air pollution on semen quality and success rates of in vitro fertilization (IVF) in humans and lower fertility rates in mice. However, no studies have evaluated the impact of air pollution on human fertility rates. We assessed the association between traffic related air pollution and fertility rates in humans in Barcelona, Spain (2011-2012). We hypothesized that higher air pollution levels would be associated with lower fertility rates. We calculated the general fertility rate which is the number of live births per 1000 women between the ages of 15 and 44 years per census tract. We used land use regression (LUR) modeling to estimate the air pollution concentrations (particulate matter, NO2/NOx) per census tract. We used Besag-York-Mollié models to quantify the relationship between air pollution and fertility rates with adjustment for a number of potential confounders such as maternal age and area level socio-economic status. We found a statistically significant reduction of fertility rates with an increase in traffic related air pollution levels, particularly for the coarse fraction of particulate matter (IRR=0.87 95% CI 0.82, 0.94 per IQR). This is the first study in humans to show an association between reduced fertility rates and higher traffic related air pollution levels. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Human rights to in vitro fertilization.

    Science.gov (United States)

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

    2013-10-01

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

  13. Mexican plants and human fertility.

    Science.gov (United States)

    Crabbe, P

    1979-07-01

    Synthetic steroids are obtainable cheaply and in abundance from sapogenins, substances originating from plants of the Discorea family. Some 40 years ago, Russell Marker, an American chemist, discovered this source, which grows abundantly in Mexican jungles and is now exploited and cultivated commercially. Today synthetic steroids prepared from extracts from a wide range of vegetable sources are used in the treatment of rheumatoid arthritis, allergies, inflammatory diseases, sterility, and various heart conditions, and form the basis of modern oral contraceptives. Nevertheless, oral contraceptives in current use are still fairly costly, and women have to be educated in their use. What is needed urgently is a cheaper contraceptive pill with a long-term effect, and research is continuing. For example, scientists from the People's Republic of China have reported significant anti-fertility effects associated with 2 substances, anordin and dinordin, prepared with steroids derived from the sisal plants Agave sisilana and Agave americana. These agents, whose anti-fertility properties have been confirmed by scientists in Sweden and the United States, constitute a new family of contraceptives with the great advantage of having to be taken only once or twice instead of 20 times per month necessary with the ordinary pill. Also from China, scientists have reported the effectiveness of gossypol as an orally administered male contraceptive, although gossypol is not a steroid. It may become, however, a leading candidate for a male contraceptive.

  14. Controlled release fertilizer workshop, 1991: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Scheib, R.M. [ed.

    1991-11-01

    Over the last 20 years the Tennessee Valley Authority`s National Fertilizer and Environmental Research Center (NFERC) has carried out a number of programs to develop controlled release fertilizers. They pioneered the development and commercialization of sulfur coated urea and conducted extensive research in an attempt to develop an economical synthesis for oxamide. In recent years there has developed an increasing interest in the environmental impact of fertilizers, particularly on the potential for ground water contamination by nitrate derived from fertilizer materials. In response to this interest NFERC`s Chemical Research Department organized a five member Controlled Release Fertilizer (CRF) Team to reassess the potential for controlled release materials in agriculture with a view to minimizing any adverse environmental impact and increasing the efficiency of nutrient utilization by the crop. This workshop was part of that reassessment program. The workshop goals were: To determine the present status of CRF research, production and use; to assess the future needs of CRF producers and consumers; and to promote communication and exchange of information. To accomplish these goals the team invited speakers from across` the United States representing academics, experimental station researchers, fertilizer producers, environmentalists, and marketing experts to present papers.

  15. Controlled release fertilizer workshop, 1991: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Scheib, R.M. (ed.)

    1991-11-01

    Over the last 20 years the Tennessee Valley Authority's National Fertilizer and Environmental Research Center (NFERC) has carried out a number of programs to develop controlled release fertilizers. They pioneered the development and commercialization of sulfur coated urea and conducted extensive research in an attempt to develop an economical synthesis for oxamide. In recent years there has developed an increasing interest in the environmental impact of fertilizers, particularly on the potential for ground water contamination by nitrate derived from fertilizer materials. In response to this interest NFERC's Chemical Research Department organized a five member Controlled Release Fertilizer (CRF) Team to reassess the potential for controlled release materials in agriculture with a view to minimizing any adverse environmental impact and increasing the efficiency of nutrient utilization by the crop. This workshop was part of that reassessment program. The workshop goals were: To determine the present status of CRF research, production and use; to assess the future needs of CRF producers and consumers; and to promote communication and exchange of information. To accomplish these goals the team invited speakers from across' the United States representing academics, experimental station researchers, fertilizer producers, environmentalists, and marketing experts to present papers.

  16. Meticulous Overview on the Controlled Release Fertilizers

    Directory of Open Access Journals (Sweden)

    Siafu Ibahati Sempeho

    2014-01-01

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

  17. [Fertility and Environmental Impacts of Urban Scattered Human Feces Used as Organic Granular Fertilizer for Leaf Vegetables].

    Science.gov (United States)

    Lü, Wen-zhou; Qiao, Yu-xiang; Yu, Ning; Shi, Rong-hua; Wang, Guang-ming

    2015-09-01

    The disposal of urban scattered human feces has become a difficult problem for the management of modern city. In present study, the scattered human feces underwent the collection, scum removal, flocculation and dehydration, finally became the granular fertilizer; the effects of the ratio of fertilizer to soil on the growth of the pakchoi and the quality of soil and leaching water were evaluated, and the feasibility of granular fertilizer manuring the pakchoi was discussed by pot experiments. The results showed that the granular fertilizer significantly enhanced the production of the pakchoi which were not polluted by the intestinal microorganisms under the experiment conditions; meanwhile, at the proper ratio of fertilizer to soil, the concentration of these microorganisms in the leaching water was lower than that in the control check. Chemical analyses of soil revealed that the nutrient content of nitrogen, phosphorus, potassium and organic matters in soil became much richer in all treatments. In addition, the granular fertilizer improved the physical- chemical properties of soil, including raising the level of soil porosity and reducing the volume weight of soil. Application of granular fertilizer won't pollute the soil or leaching water; instead, it can also prevent nitrogen, potassium and intestinal microorganisms from leaching inio ground water at the proper ratio of granular fertilizer to soil.

  18. Behavior genetic modeling of human fertility

    DEFF Research Database (Denmark)

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

    2001-01-01

    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......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...

  19. Marital moratorium and fertility control in China.

    Science.gov (United States)

    Tien, H Y

    1970-11-01

    Abstract Since 1949, the issue of marital postponement has been extensively discussed in China. Unlike some other means of fertility control (e.g. abortion and oral contraception), marital postponement has been welcomed with the fewest misgivings. Lately, marital postponement has also been given renewed emphasis by those outside China who see a weak link between various current national family planning programmes based on improved technology and the goal of fertility reduction. One aim of this paper is to render a comprehensive account of the marital postponement programme in China in the course of the birth control campaign during the last two decades. The second objective is to discuss the lessons that may be learned from it, and its implications for the current fertility controversy in the United States. Four general conclusions emerge from a careful analysis of the available documents: (1) in China, proponents of delayed marriage were divided on the question of how to secure its general acceptance. One issue dividing them was whether or not China's Marriage Law of 1950 should be amended in order to achieve it. Those who favoured raising the minimum legal age disagreed on the details of the presumably needed change. There is enough evidence to suggest that medical personnel were the chief advocates of compulsory postponement of marriage. The government rejected this legalistic approach and, in so doing, agreed with Chen Ta (a noted demographer) and others who sought to achieve postponement of marriage through appropriate social and economic measures. (2) Decisions to delay matrimony in different socio-cultural settings are not necessarily identical sociological phenomena. In some societies, (e.g. the United States), they may amount to no more than a course of action that enables individuals involved to realize or develop alternate goals in life. In others (e.g. China), they are literally acts of rebellion. (3) The fertility policy dispute has been carried on in

  20. 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.

  1. Follicle-stimulating hormone administered at the time of human chorionic gonadotropin trigger improves oocyte developmental competence in in vitro fertilization cycles: a randomized, double-blind, placebo-controlled trial.

    Science.gov (United States)

    Lamb, Julie D; Shen, Shehua; McCulloch, Charles; Jalalian, Liza; Cedars, Marcelle I; Rosen, Mitchell P

    2011-04-01

    To determine whether an additional follicle-stimulating hormone (FSH) bolus administered at the time of the human chorionic gonadotropin (hCG) trigger can improve the developmental competence of the oocyte. Randomized, double-blind, placebo-controlled, clinical trial. Academic medical center. Women undergoing a long agonist suppression in vitro fertilization (IVF) protocol for treatment of infertility. FSH bolus at time of hCG trigger versus placebo. Primary outcome; fertilization; secondary outcomes: oocyte recovery, implantation rate, and clinical and ongoing pregnancy/live birth rates. A total of 188 women (mean age: 36.2 years; range: 25 to 40 years) were randomized. Fertilization (2PN/#oocyte) was statistically significantly improved in the treatment arm (63% vs. 55%) as was the likelihood of oocyte recovery (70% vs. 57%). There was no statistically significant difference in clinical pregnancy rate (56.8% vs. 46.2%) or ongoing/live birth rate (51.6% vs. 43.0%). Improvements in IVF success rates have largely been due to optimization of embryo culture and stimulation protocols; less attention has been directed toward methods to improve induction of final oocyte maturation. This was the first randomized, double-blind, placebo-controlled trial to modify the ovulation trigger to improve oocyte competence, as demonstrated by the statistically significant improvement in fertilization. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  2. Pituitary gonodal axis in fertile and infertile human males

    Energy Technology Data Exchange (ETDEWEB)

    Hafiez, A.A.; Mahmoud, K.Z.; Abbas, E.Z.; Halawa, F. (Cairo Univ. (Egypt))

    1984-08-01

    Radioimmunoassays of serum PRL, LH, FSH, testosterone and estradiol were performed in normal fertile subjects and infertile patients. The findings in the fertile group suggest that prolactin in human males has a role in steroidogenesis. Oligospermic and azospermic patients revealed hormonal patterns which were significantly higher than in the fertile group. Hyperprolactinemia was found in most cases of both infertile groups indicating that PRL has a significant role.

  3. Life-history theory, fertility and reproductive success in humans.

    Science.gov (United States)

    Strassmann, Beverly I; Gillespie, Brenda

    2002-03-22

    According to life-history theory, any organism that maximizes fitness will face a trade-off between female fertility and offspring survivorship. This trade-off has been demonstrated in a variety of species, but explicit tests in humans have found a positive linear relationship between fitness and fertility. The failure to demonstrate a maximum beyond which additional births cease to enhance fitness is potentially at odds with the view that human fertility behaviour is currently adaptive. Here we report, to our knowledge, the first clear evidence for the predicted nonlinear relationship between female fertility and reproductive success in a human population, the Dogon of Mali, West Africa. The predicted maximum reproductive success of 4.1+/-0.3 surviving offspring was attained at a fertility of 10.5 births. Eighty-three per cent of the women achieved a lifetime fertility level (7-13 births) for which the predicted mean reproductive success was within the confidence limits (3.4 to 4.8) for reproductive success at the optimal fertility level. Child mortality, rather than fertility, was the primary determinant of fitness. Since the Dogon people are farmers, our results do not support the assumptions that: (i) contemporary foragers behave more adaptively than agriculturalists, and (ii) that adaptive fertility behaviour ceased with the Neolithic revolution some 9000 years ago. We also present a new method that avoids common biases in measures of reproductive success.

  4. Perfluoroalkyl and polyfluoroalkyl substances and measures of human fertility

    DEFF Research Database (Denmark)

    Bach, Cathrine Carlsen; Vested, Anne; Jørgensen, Kristian Tore

    2016-01-01

    epidemiologic evidence on the association between exposure to PFASs and measures of human fertility, with particular emphasis on perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA). Systematic literature searches were initially conducted in MEDLINE and EMBASE and subsequently in references...

  5. Heart Disease: A Price Humans Pay for Fertility?

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_166826.html Heart Disease: A Price Humans Pay for Fertility? Study finds ... 22, 2017 (HealthDay News) -- Certain genes linked to heart disease may also improve your chances of having children, ...

  6. Chemical analysis of substrates with controlled release fertilizer

    NARCIS (Netherlands)

    Kreij, de C.

    2004-01-01

    Water-soluble fertilizer added to media containing controlled release fertilizer cannot be analysed with the 1:1.5 volume water extract, because the latter increases the element content in the extract. During storage and stirring or mixing the substrate with the extractant, part of the controlled re

  7. Controlled release fertilizer improves quality of container longleaf pine seedlings

    Science.gov (United States)

    R. Kasten Dumroese; Jeff Parkhurst; James P. Barnett

    2005-01-01

    In an operational trial, increasing the amount of nitrogen (N) applied to container longleaf pine seedlings by incorporating controlled release fertilizer (CRF) into the media improved seedling growth and quality. Compared with control seedlings that received 40 mg N, seedlings receiving 66 mg N through CRF supplemented with liquid fertilizer had needles that were 4 in...

  8. Chemical analysis of substrates with controlled release fertilizer

    NARCIS (Netherlands)

    Kreij, de C.

    2004-01-01

    Water-soluble fertilizer added to media containing controlled release fertilizer cannot be analysed with the 1:1.5 volume water extract, because the latter increases the element content in the extract. During storage and stirring or mixing the substrate with the extractant, part of the controlled re

  9. 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.

  10. 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…

  11. 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…

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

    OpenAIRE

    Sempeho Ibahati Siafu

    2017-01-01

    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,...

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

    OpenAIRE

    Sempeho Ibahati Siafu

    2017-01-01

    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,...

  14. Encapsulated Urea-Kaolinite Nanocomposite for Controlled Release Fertilizer Formulations

    National Research Council Canada - National Science Library

    Sempeho, Siafu Ibahati; Kim, Hee Taik; Mubofu, Egid; Pogrebnoi, Alexander; Shao, Godlisten; Hilonga, Askwar

    2015-01-01

    Urea controlled release fertilizer (CRF) was prepared via kaolinite intercalation followed by gum arabic encapsulation in an attempt to reduce its severe losses associated with dissolution, hydrolysis, and diffusion...

  15. Evolutionary contributions to the study of human fertility.

    Science.gov (United States)

    Sear, Rebecca

    2015-01-01

    Demography, lacking an overarching theoretical framework of its own, has drawn on theories in many other social sciences to inform its analyses. The aim of this paper is to bring to the demographic community's attention research in the evolutionary sciences on fertility, and to demonstrate that evolutionary theory can be another useful tool in the demographer's toolkit. I first dispel some myths which impede the incorporation of evolutionary theory into demography: I make it clear that evolutionary explanations do not assume that all human behaviour is hardwired and functions to maximize genetic fitness; that they are able to explain variation in human behaviour; and that they are not necessarily alternatives to social science explanations. I then describe the diversity of work on fertility by evolutionary researchers, particularly human evolutionary ecologists and cultural evolutionists, and illustrate the usefulness of the evolutionary approach with examples of its application to age at first birth and the fertility transition.

  16. Human Capital, Fertility, and Economic Growth

    OpenAIRE

    Gary S. Becker; Murphy, Kevin M.; Robert F. Tamura

    1990-01-01

    Our model of growth departs from both the Malthusian and neoclassical approaches by including investments in human capital. We assume, crucially, that rates of return on human capital investments rise, rather than, decline, as the stock of human capital increases, until the stock becomes large. This arises because the education sector uses human capital note intensively than either the capital producing sector of the goods producing sector. This produces multiple steady scares: an undeveloped...

  17. Controlled-release fertilizer(CRF):A green fertilizer for controlling non-point contamination in agriculture

    Institute of Scientific and Technical Information of China (English)

    MAO Xiao-yun; SUN Ke-jun; WANG De-han; LIAO Zong-wen

    2005-01-01

    Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N2O) and eutrophication of water bodies. How to solve this problem has become a serious challenge, especially for China as its high ecological pressure. Controlled-release fertilizer(CRF) has been developed to minimize the contamination while keeping high yield and has become a green fertilizer for agriculture. Several CRFs made with special coating technology were used for testing the fertilizer effects in yield and environment through pot experiment and field trial. The result indicated that the CRFs had higher N use efficiency, thus reducing N loss through leaching and volatilization while keeping higher yields. Comparing with imported standard CRFs,the test on CRFs showed similar fertilizer effect but with much lower cost. CRFs application is becoming a new approach for minimizing non-point contamination in agriculture.

  18. LEUKEMIA INHIBITORY FACTOR IN FERTILE AND INFERTILE HUMAN REPRODUCTIVE TRACT IN VIVO

    Directory of Open Access Journals (Sweden)

    M. Ghaffari

    2000-01-01

    Full Text Available Maternal leukemia inhibitory factor (LIF is required for successful implanta¬tion in mice, but little is known about its role and expression in human reproduc¬tion. Here we report on the pattern of LIF mRNA expression in 30 samples of previously fertile and 11 infertile human endometrium, 10 samples of previously fertile post-menopausal endometrium and 10 uterine (Fallopian tubes from pre¬viously fertile women using the reverse transcriptase-polymerase chain reaction (RT-PCR. All samples were removed with informed patient consent and Ethical Sheffield university Committee approval. Pieces of each sample were processed for electron microscopy to confirm tissue normality and stage of cycle. LIF mRNA was expressed throughout most of the secretory phase (from about day 18 of the cycle and menstruation phase (days 1-4 of cycles in fertile women. However it was not expressed during the proliferative phase. In addition LIF mRNA was absent from the uterine tube at all stages of the cycle and from the postmeno¬pausal and infertile tissue. These results suggest that LIF is expressed in a men¬strual cycle-dependent manner in fertile human endometrium and its expression is likely to be under hormonal control and is not dependent on pregnancy. In addition, our results showed lack of LIF production in infertile women, which may suggest a role for LIF in fertility.

  19. 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...... of consanguinity's deleterious effects affecting an entire human population is provided...

  20. Human Fertility, Molecular Genetics, and Natural Selection in Modern Societies

    NARCIS (Netherlands)

    Tropf, Felix C.; Stulp, Gert; Barban, Nicola; Visscher, Peter M.; Yang, Jian; Snieder, Harold; Mills, Melinda C.

    2015-01-01

    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

  1. FERLENT - a controlled release fertilizer produced from a polymer material

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    The possibility to use release controlled fertilizers in the agriculture of the tropical countries is more important than in the agriculture of the countries of the template regions. In this context, this work purpose the development of a new Fertilizer of Controlled Release named FERLENT, which was obtained starting from a polymeric material, under controlled conditions which allowed to corroborate the adjustment of the synthesis parameters under the modulate of nutrients liberation. It was characterized by, Scanning Microscopy Electron (SEM), Thermogravimetric analysis (TGA), Nuclear Magnetic Resonance (NMR) and infrared spectroscopy (FTIR). (author)

  2. Role of zona pellucida glycoproteins during fertilization in humans.

    Science.gov (United States)

    Gupta, Satish Kumar

    2015-04-01

    In the last decade, scientific investigations pertaining to the role of zona pellucida (ZP) glycoproteins during fertilization in humans have led to new insights. This has been achieved using purified native/recombinant human zona proteins and transgenic mice expressing human ZP glycoproteins. The proposed model in mice of ZP glycoprotein-3 (ZP3) acting as primary sperm receptor and ZP glycoprotein-2 (ZP2) as secondary sperm receptor has been modified for sperm-egg binding in humans. ZP glycoprotein-1 (ZP1), ZP3, and ZP glycoprotein-4 (ZP4) have been shown to bind to the capacitated human sperm. ZP2 binds to the acrosome-reacted human spermatozoa. Further, the eggs obtained from transgenic mice expressing human ZP2 alone or in conjunction with other human instead of mouse zona proteins showed binding of human sperm, suggesting that ZP2 might also play a role in sperm-egg binding. This function has been mapped to a domain corresponding to amino acid residues 51-144 of ZP2. In contrast to mice, where ZP3 is the primary agonist for inducing the acrosome reaction, in humans, the acrosome reaction can be mediated by ZP1, ZP3, and ZP4. The effect of mutations in the genes encoding zona proteins on the ZP morphology and infertility has not been established. Further, the role of autoantibodies against ZP in women with 'unexplained infertility' leading to poor outcome of in vitro fertilization is currently controversial and needs further investigations. Understanding the role of ZP glycoproteins during human fertilization facilitates the development of new contraceptives and strategies to overcome the problem of infertility.

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

    Science.gov (United States)

    Lee, Ronald; Mason, Andrew

    2010-05-01

    Do low fertility and population aging lead to economic decline if couples have fewer children, but invest more in each child? By addressing this question, this article extends previous work in which the authors show that population aging leads to an increased demand for wealth that can, under some conditions, lead to increased capital per worker and higher per capita consumption. This article is based on an overlapping generations (OLG) model which highlights the quantity-quality tradeoff and the links between human capital investment and economic growth. It incorporates new national level estimates of human capital investment produced by the National Transfer Accounts project. Simulation analysis is employed to show that, even in the absence of the capital dilution effect, low fertility leads to higher per capita consumption through human capital accumulation, given plausible model parameters.

  4. Artificial oocyte activation in intracytoplasmic sperm injection cycles using testicular sperm in human in vitro fertilization.

    Science.gov (United States)

    Kang, Hee Jung; Lee, Sun-Hee; Park, Yong-Seog; Lim, Chun Kyu; Ko, Duck Sung; Yang, Kwang Moon; Park, Dong-Wook

    2015-06-01

    Artificial oocyte activation (AOA) is an effective method to avoid total fertilization failure in human in vitro fertilization-embryo transfer (IVF-ET) cycles. AOA performed using a calcium ionophore can induce calcium oscillation in oocytes and initiate the fertilization process. We evaluated the usefulness of AOA with a calcium ionophore in cases of total fertilization failure in previous cycles and in cases of severe male factor infertility patients with non-motile spermatozoa after pentoxifylline (PF) treatment. The present study describes 29 intracytoplasmic sperm injection (ICSI)-AOA cycles involving male factor infertility at Cheil General Hospital from January 2006 to June 2013. Patients were divided into two groups (control, n=480; AOA, n=29) depending on whether or not AOA using a calcium ionophore (A23187) was performed after testicular sperm extraction-ICSI (TESE-ICSI). The AOA group was further split into subgroups according to sperm motility after PF treatment: i.e., motile sperm-injected (n=12) and non-motile sperm-injected (n=17) groups (total n=29 cycles). The good embryo rate (52.3% vs. 66.9%), pregnancy rate (20.7% vs. 52.1%), and delivery rate (10.3% vs. 40.8%) were lower in the PF/AOA group than in the control group. When evaluating the effects of restoration of sperm motility after PF treatment on clinical outcomes there was no difference in fertilization rate (66.6% vs. 64.7% in non-motile and motile sperm, respectively), pregnancy rate (17.6% vs. 33.3%), or delivery rate (5.9% vs. 16.7%) between the two groups. We suggest that oocyte activation is a useful method to ensure fertilization in TESE-ICSI cycles regardless of restoration of sperm motility after PF treatment. AOA may be useful in selected patients who have a low fertilization rate or total fertilization failure.

  5. Controlled root targeted delivery of fertilizer using an ionically crosslinked carboxymethyl cellulose hydrogel matrix

    OpenAIRE

    Davidson, Drew W; Verma, Mohit S; Gu, Frank X

    2013-01-01

    Aims The recent increases in food prices caused by the corresponding increases in fertilizer costs have highlighted the demand for reducing the overuse of fertilizers in industrial agriculture. There has been increasing interest in developing plant root-targeted delivery (RTD) of fertilizers in order to address the problem of inefficient fertilizer use. The aim of this study is to develop a low cost controlled release device to deliver fertilizers to plant roots and thereby increase fertilize...

  6. Controlled root targeted delivery of fertilizer using an ionically crosslinked carboxymethyl cellulose hydrogel matrix

    OpenAIRE

    Davidson, Drew W; Mohit S. Verma; Gu, Frank X.

    2013-01-01

    Aims The recent increases in food prices caused by the corresponding increases in fertilizer costs have highlighted the demand for reducing the overuse of fertilizers in industrial agriculture. There has been increasing interest in developing plant root-targeted delivery (RTD) of fertilizers in order to address the problem of inefficient fertilizer use. The aim of this study is to develop a low cost controlled release device to deliver fertilizers to plant roots and thereby increase fertilize...

  7. Stored human urine supplemented with wood ash as fertilizer in tomato (Solanum lycopersicum) cultivation and its impacts on fruit yield and quality.

    Science.gov (United States)

    Pradhan, Surendra K; Holopainen, Jarmo K; Heinonen-Tanski, Helvi

    2009-08-26

    This study evaluates the use of human urine and wood ash as fertilizers for tomato cultivation in a greenhouse. Tomatoes were cultivated in pots and treated with 135 kg of N/ha applied as mineral fertilizer, urine + ash, urine only, and control (no fertilization). The urine fertilized plants produced equal amounts of tomato fruits as mineral fertilized plants and 4.2 times more fruits than nonfertilized plants. The levels of lycopene were similar in tomato fruits from all fertilization treatments, but the amount of soluble sugars was lower and Cl(-) was higher in urine + ash fertilized tomato fruits. The beta-carotene content was greater and the NO(3)(-) content was lower in urine fertilized tomato fruits. No enteric indicator microorganisms were detected in any tomato fruits. The results suggest that urine with/without wood ash can be used as a substitute for mineral fertilizer to increase the yields of tomato without posing any microbial or chemical risks.

  8. Human fertility and land tenure in highland Bolivia.

    Science.gov (United States)

    Godoy, R A

    1984-01-01

    Basic demographic data of landless and landed peasants from the highlands and valley of Northern Potosi, Bolivia, are compared. Household size and crude birth rates are larger in the highlands than in the valley. Within the highland population, no statistically significant difference was observed between the age-specific fertility of landless and landed women, nor in the survivorship ratio of their offspring. The prevalence of exchange and reciprocity at the village level may be responsible for the absence of important differences in the fertility and mortality patterns of the landed and the landless. Information was obtained from a total of 333 households, which included a population of about 1700 people or 20% of the Jukumani ayllu (ethnic group). No relationship between altitude and human reproduction was noted among Jukumanis. Highland Jukumani women begin reproducing in their late teens; by their mid-20s only about 30% of the 21-25 year old female cohort remains childless. 2 major tax categories of people emerge in the area under consideration: taseros, the landed peasantry who are obligated to pay taxes, and kantu runas, the landless laborers who do not pay taxes. Tasero women are most fertile from their mid-20s until their mid-30s whild kantu runa women are more fertile later in life. Within the highland territory there are no statistically significant differences in the infant and child mortality patterns of taseros and kantu runas. The higher household size and crude birth rates of highlanders suggests that hypoxic stress may not depress fertility. Taseros and kantu runas differ in fertility patterns in degree rather than in kind. It is concluded that although differential access to natural resources may translate into slightly higher crude birth rates and child/woman ratios, it does not have much bearing on the fertility of women, or the mortality or household size of taxpayers and kantu runas. A possible explanation for the Jukumani anomaly may be the

  9. 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.

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

    Science.gov (United States)

    Tropf, Felix C; Stulp, Gert; Barban, Nicola; Visscher, Peter M; Yang, Jian; Snieder, Harold; Mills, Melinda C

    2015-01-01

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  12. Encapsulated Urea-Kaolinite Nanocomposite for Controlled Release Fertilizer Formulations

    OpenAIRE

    Siafu Ibahati Sempeho; Hee Taik Kim; Egid Mubofu; Alexander Pogrebnoi; Godlisten Shao; Askwar Hilonga

    2015-01-01

    Urea controlled release fertilizer (CRF) was prepared via kaolinite intercalation followed by gum arabic encapsulation in an attempt to reduce its severe losses associated with dissolution, hydrolysis, and diffusion. Following the beneficiation, the nonkaolinite fraction decreased from 39.58% to 0.36% whereas the kaolinite fraction increased from 60.42% to 99.64%. The X-ray diffractions showed that kaolinite was a major phase with FCC Bravais crystal lattice with particle sizes ranging betwee...

  13. Encapsulated Urea-Kaolinite Nanocomposite for Controlled Release Fertilizer Formulations

    OpenAIRE

    Siafu Ibahati Sempeho; Hee Taik Kim; Egid Mubofu; Alexander Pogrebnoi; Godlisten Shao; Askwar Hilonga

    2015-01-01

    Urea controlled release fertilizer (CRF) was prepared via kaolinite intercalation followed by gum arabic encapsulation in an attempt to reduce its severe losses associated with dissolution, hydrolysis, and diffusion. Following the beneficiation, the nonkaolinite fraction decreased from 39.58% to 0.36% whereas the kaolinite fraction increased from 60.42% to 99.64%. The X-ray diffractions showed that kaolinite was a major phase with FCC Bravais crystal lattice with particle sizes ranging betwee...

  14. Innovative use of controlled availability fertilizers with high performance for intensive agriculture and environmental conservation

    Institute of Scientific and Technical Information of China (English)

    Sadao SHOJI

    2005-01-01

    A variety of slow release fertilizers, controlled release (availability) fertilizers (CAFs),and stability fertilizers have been developed in response to the serious drawbacks of the conventional fertilizers since the early 1960's. Of these fertilizers, CAFs which are coated with resin are consumed in the largest quantity in the world. Selecting CAFs with higher performance, the author will discuss about: 1) Innovation of agro-technologies for various field crops including new concepts of fertilizer application, 2) high yielding of field crops, 3) enhancing quality and safety of farm products, and 4) controlling the adverse effect of intensive agriculture on the environment.

  15. Controlled-release fertilizer composition substantially coated with an impermeable layer

    Energy Technology Data Exchange (ETDEWEB)

    Ankeny, Mark

    2016-03-29

    A controlled-release fertilizer composition is provided that is substantially coated with an impermeable layer. The fertilizer composition may further include one or more hollow sections to allow for root penetration and efficient delivery of nutrients.

  16. [Research advances on controlled-release mechanisms of nutrients in coated fertilizers].

    Science.gov (United States)

    Zhang, Haijun; Wu, Zhijie; Liang, Wenju; Xie, Hongtu

    2003-12-01

    Using encapsulation techniques to coat easily soluble fertilizers is an important way to improve fertilizer use efficiency while reduce environmental hazards. Based on a wide range of literature collection on coated fertilizer research, the theories, processes, and characters of nutrient controlled-release from coated fertilizer were discussed, and the factors affecting nutrient controlled-release and the mathematical simulations on it were reviewed. The main tendencies related to this research in China were also put forward.

  17. Human responses to Florida red tides: policy awareness and adherence to local fertilizer ordinances.

    Science.gov (United States)

    Kirkpatrick, Barbara; Kohler, Kate; Byrne, Margaret; Fleming, Lora E; Scheller, Karen; Reich, Andrew; Hitchcock, Gary; Kirkpatrick, Gary; Ullmann, Steven; Hoagland, Porter

    2014-09-15

    To mitigate the damages of natural hazards, policy responses can be beneficial only if they are effective. Using a self-administered survey approach, this paper focuses on the adherence to local fertilizer ordinances (i.e., county or municipal rules regulating the application of fertilizer to private lawns or facilities such as golf courses) implemented in jurisdictions along the Southwest Florida coast in response to hazardous blooms of Florida red tides (Karenia brevis). These ordinances play a role in the context of evolving programs of water pollution control at federal, state, water basin, and local levels. With respect to policy effectiveness, while the strength of physical linkages is of critical importance, the extent to which humans affected are aware of and adhere to the relevant rules, is equally critical. We sought to understand the public's depth of understanding about the rationales for local fertilizer ordinances. Respondents in Sarasota, Florida, were asked about their fertilizer practices in an area that has experienced several major blooms of Florida red tides over the past two decades. A highly educated, older population of 305 residents and "snowbirds" reported relatively little knowledge about a local fertilizer ordinance, its purpose, or whether it would change the frequency, size, or duration of red tides. This finding held true even among subpopulations that were expected to have more interest in or to be more knowledgeable about harmful algal blooms. In the face of uncertain science and environmental outcomes, and with individual motivations at odds with evolving public policies, the effectiveness of local community efforts to decrease the impacts of red tides may be compromised. Targeted social-science research on human perceptions about the risks of Florida red tides and education about the rationales for potential policy responses are warranted.

  18. Human papillomavirus infection and fertility alteration: a systematic review.

    Science.gov (United States)

    Souho, Tiatou; Benlemlih, Mohamed; Bennani, Bahia

    2015-01-01

    HPV is the most prevalent sexually transmitted infection and its effect in cancer induction is well documented. HPV infections are mostly asymptomatic, but it is unclear whether HPV infections can result in alterations of reproductive health. To determine the relationship between human papillomavirus infections and reproductive health in both men and women. A systematic literature review was performed in PubMed and ScienceDirect data bases from January 1994 through August 2014. HPV infections are shown to be significantly associated to many adverse effects in the reproductive function. These adverse effects were reported in different levels from cells production to pregnancy and may be related to the infecting genotype. It appears from this study that HPV detection and genotyping could be of great value in infertility diagnosis at least in idiopathic infertility cases. Like for the risk of carcinogenesis, another classification of HPV regarding the risk of fertility alteration may be considered after deep investigations.

  19. Variable Fertilizer Control System for Deep-fertilization Liquid Fertilizer Applicator%深施型液态肥变量施肥控制系统

    Institute of Scientific and Technical Information of China (English)

    郎春玲; 王金武; 王金峰; 何剑南; 郗晓焕

    2013-01-01

    A control system for variahle rate fertilization, which depends on deep-fertilization liquid fertilizer applicator, was introduced. The single chip microcomputer was used as core processor and electromagnetic proportion regulator valve was used as execution unit. Software was designed for selecting data and sending commands. The test results in the test-bed showed that the system can complete the control of variable rate fertilization and the error of the variable fertilizing was less than 0. 5 mL in each time, which meets the liquid fertilizer variables requirement.%以深施型液态施肥机为依托,采用单片机作为核心处理器,以电磁比例调节阀为执行部件,设计了深施型液态变量施肥控制系统.设计了与硬件配套的上位机软件,用于采集数据与发送命令.喷肥针施肥量控制误差台架试验结果表明,该系统可实现深施型液态变量施肥,施肥误差不超过0.5 mL/次,满足液态变量施肥作业要求.

  20. 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...

  1. The Effects of Controlled Release Fertilizer and Conventional Complex Fertilizer on the Photosynthetic Characteristics in Winter Wheat

    Directory of Open Access Journals (Sweden)

    Guoqing Li

    2014-11-01

    Full Text Available The quantity and quality of the fertilizers affected the photosynthetic characteristic of the winter wheat. So, the rationality applied, reduced fertilizers not only can decline pollution for soil and ground water, but also save the cost. The quantity and quality of the fertilizers determine the relationship between the photosynthetic characteristics. Therefore, the different effects about the using of the Controlled Release Fertilizer (CRF and the Conventional Complex Fertilizer (CCF on photosynthetic characteristics in winter wheat were studied in the open field by pots experiment. The results showed that the SPAD value, photosynthetic rate and stomatal conductance of the treatments of the mixture of the CRF and equivalent CCF applied were higher than that of the treatments of CRF used alone and the control treatment, but the intercellular carbon dioxide concentration of both latter was higher than that of the former. So it can conclude that it was the best way to maintain higher photosynthetic rate in winter wheat by using the amount application and the way of application of fertilizer of T6.

  2. Design and Experiment of Slave Computer Control System for Applying Variable-rate Liquid Fertilizer

    Institute of Scientific and Technical Information of China (English)

    Zhang Ying-zi; Chen Hai-tao; Hou Shou-yin; Ji Wen-yi; Ouyang Bin-lin; Dun Guo-qiang; Zhang Ji-cheng

    2015-01-01

    In order to increase the applying rate of liquid fertilizer and reduce environmental pollution, a slave computer control system for applying variable-rate liquid fertilizer was designed. The system used SMC as core processor and electrically controlled pressure regulator as execution component. The characteristic equation of the system was obtained by using classical control theory. Results indicated that the characteristic equation met the requirements of routh-criterion, which indicated the working process of the system was stable. Performance of the slave computer was verified via bench tests. Results demonstrated that there was no significant influence on the response from interclass error. The fertilization error was less than 0.9, and the fertilization accuracy was larger than 97%. The liquid fertilizer emitted by the fertilizing devices had no significant difference in uniformity, which met the demands of the slave computer control system for applying variable-rate liquid fertilizer.

  3. How contemporary human reproductive behaviors influence the role of fertility-related genes: the example of the p53 gene.

    Directory of Open Access Journals (Sweden)

    Rosa Maria Corbo

    Full Text Available Studies on human fertility genes have identified numerous risk/protective alleles involved in the occurrence of reproductive system diseases causing infertility or subfertility. Investigations we carried out in populations at natural fertility seem to suggest that the clinical relevance that some fertility genes are now acquiring depends on their interaction with contemporary reproductive behaviors (birth control, delayed childbearing, and spacing birth order, among others. In recent years, a new physiological role in human fertility regulation has emerged for the tumor- suppressor p53 gene (P53, and the P53 Arg72Pro polymorphism has been associated with recurrent implantation failure in humans. To lend support to our previous observations, we examined the impact of Arg72Pro polymorphism on fertility in two samples of Italian women not selected for impaired fertility but collected from populations with different (premodern and modern reproductive behaviors. Among the women at near-natural fertility (n = 98, the P53 genotypes were not associated with different reproductive efficiency, whereas among those with modern reproductive behaviors (n = 68, the P53 genotypes were associated with different mean numbers of children [Pro/Pro = 0.75fertility genes may have become "detrimental" following exposure to modern reproductive patterns and might therefore be associated with reduced reproductive success. Set within an evolutionary framework, this change could lead to the selection of a set of gene variants fitter to current reproductive behaviors as the

  4. Spontaneous fertility and in vitro fertilization outcome: new evidence of human papillomavirus sperm infection.

    Science.gov (United States)

    Garolla, Andrea; Engl, Bruno; Pizzol, Damiano; Ghezzi, Marco; Bertoldo, Alessandro; Bottacin, Alberto; Noventa, Marco; Foresta, Carlo

    2016-01-01

    To evaluate the reproductive outcome of infertile couples undergoing assisted reproduction techniques (ART) with or without human papillomavirus (HPV) semen infection. Cross-sectional clinical study. Units of andrology, reproductive medicine, and gynecology. A total of 226 infertile couples. Male partners were evaluated by means of fluorescence in situ hybridization (FISH) for HPV on semen. After a diagnostic period, female partners underwent intrauterine insemination (IUI) or intracytoplasmic sperm injection (ICSI). Seminal parameters and FISH analysis for HPV in sperm head. Spontaneous or assisted pregnancies, live births, and miscarriages were recorded. Statistical analysis included unpaired Student t test and chi-square test. Fifty-four male partners (23.9%) had HPV semen infection confined to sperm, confined to exfoliated cells, or in both cells. During the diagnostic period, noninfected couples showed spontaneous pregnancies. IUI and ICSI treatments were performed in, respectively, 60 and 98 noninfected and in 21 and 33 infected couples, with 38.4% and 14.2% cumulative pregnancy rates, respectively. The follow-up of pregnancies showed a higher miscarriage rate in infected couples (62.5% vs. 16.7%). Ongoing pregnancies of the latter group were characterized by HPV infection confined to exfoliated cells. A reduction in natural and assisted cumulative pregnancy rate and an increase in miscarriage rate are related to the presence of HPV at sperm level. Although the exact mechanism by which sperm infection is able to impair fertility remains unclear, this aspect is worthy of further investigations. If confirmed, these results could change the clinical and diagnostic approach to infertile couples. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  5. Evolutionary approach to understand human low fertility phenomenon

    CERN Document Server

    Černák, Jozef

    2016-01-01

    Is it possible to turn the low fertility? We think that more radical change of the global economy is needed that will stimulate series of self-regulation processes and evolution toward the safe fertility. Proposed changes should stimulate more uniform spatial distribution of production and wealth usage, increase in a number of self-sufficient territories, decrease of labor mobility and social mobility and careful consideration of a biological nature of fertility in economical or social actions.

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

    Science.gov (United States)

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

    2014-03-01

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

  7. The Effects of Different Amounts of Controlled Release Fertilizer on the Root Growth and the Filling Rate in Winter Wheat

    Directory of Open Access Journals (Sweden)

    Meng Li

    2014-03-01

    Full Text Available In order to increase the fertilizer use efficiency and yield in winter wheat, the effects of controlled release fertilizer on the root growth and the filling rate in winter wheat by applying different amounts of controlled release fertilizer had been studied in open field. The results indicated that conventional complex fertilizer and controlled release fertilizer could cause corresponding changes of the wheat root activity, dry root weight, root-shoot ratio and filling rate, but the fertilizer of conventional fertilizer performed in the pre-stage significantly, controlled release fertilizer performed in the middle and late stage gradually. So mixing conventional fertilizer with controlled release fertilizer can ensure the nutrient supply of whole growth and development of wheat to explore the most appropriate collocation dosage. This will make fertilizer and economic benefits achieve the best.

  8. Effect of Kelp Residue Microbial Fertilizer on Eco-Control Peanut Pathogenic Fungus Aspergillus Parasiticus 1

    Institute of Scientific and Technical Information of China (English)

    Wei Xiao; Peisheng Yan

    2016-01-01

    Ecological prevention and control of plant disease is very important in sustainable agriculture. Adjusting soil pH value and fertilizing organic microbial fertilizer are two effective measures in this process. Kelp residue contains a large amount of organic compounds and alkaline metal ions. The bio⁃control Bacillus amyloliquefaciens strain Hitwh⁃BA2 was inoculated into kelp residue medium to produce kelp residue microbial fertilizer. Acidic soil and alkaline soil were used to study the effect of kelp residue microbial fertilizer on soil pH and soil suppressive activity. Tip⁃culture method was used to determine soil leachate suppressive activity, which characterized the soil suppressive activity. Results showed that fertilizing kelp residue microbial fertilizer had increased the soil pH and soil suppressive ability significantly, which was verified by peanut validation experiments as well. Peanut potting experiments proved that fertilizing kelp residue microbial fertilizer not only improved the yield of peanuts obviously, but also reduced the amount of Aspergillus parasiticus 95 in peanut geocarposphere soil significantly. Results also showed that fertilizing kelp residue microbial fertilizer was effective in reducing A. parasiticus 95 infection rate. So the kelp residue microbial fertilizer has good potential application prospect on ecological prevention and control of plant disease.

  9. Aquaporin-11 control of testicular fertility markers in Syrian hamsters.

    Science.gov (United States)

    Shannonhouse, John L; Urbanski, Henryk F; Woo, Shih-Lung; Fong, Li An; Goddard, Scott D; Lucas, William F; Jones, Edward R; Wu, Chaodong; Morgan, Caurnel

    2014-06-25

    The present study sought novel changes to the hamster testicular transcriptome during modulation of fertility by well-characterized photoperiodic stimuli. Transition from long days (LD, 14 h light/day) to short days (SD, 10h light/day) triggered testicular regression (61% reduction of testis weight, relative to LD) in SD-sensitive (SD-S) hamsters within 16 weeks. After 22 weeks of SD exposure, a third cohort of hamsters became SD-refractory (SD-R), and exhibited testicular recrudescence (137% testis weight gain, relative to SD-S). Partial interrogation of the testicular transcriptome by annealing-control-primer-modified differential display PCR provided several candidates for regulation of testicular functions. Multiple linear regression modeling indicated the best correlation for aquaporin 11 (Aqp11) with changes in testis weight. Correlations were also strongest for Aqp11 with expression levels of reference cDNAs that control spermatogenesis (Hspa2 and Tnp2), steroidogenesis (Cox2, 3βHsd, and Srebp2), sperm motility (Catsper1, Pgk2, and Tnp2), inflammation (Cox2), and apoptosis (Bax and Bcl2). Moreover, siRNA-mediated knockdown of testicular Aqp11 mRNA and protein reduced Hspa2 and Tnp2 mRNA levels, and it increased 3βHsd mRNA levels. It also reduced mRNA levels for Sept12, which is a testis-specific inducer of spermatogenesis. These results suggest a central role for testicular Aqp11 signaling in the coordinate regulation of crucial components of fertility. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  10. [Effects of sulfur- and polymer-coated controlled release urea fertilizers on wheat yield and quality and fertilizer nitrogen use efficiency].

    Science.gov (United States)

    Ma, Fu-Liang; Song, Fu-Peng; Gao, Yang; Zou, Peng

    2012-01-01

    A field experiment was conducted to study the effects of sulfur- and polymer-coated controlled release urea fertilizers on wheat yield and its quality, plow layer soil inorganic nitrogen (N) contents, and fertilizer N use efficiency. Compared with traditional urea fertilizer, both sulfur- and polymer-coated controlled release urea fertilizers increased the grain yield by 10.4%-16.5%, and the grain protein and starch contents by 5.8%-18.9% and 0.3%-1.4%, respectively. The controlled release urea fertilizers could maintain the topsoil inorganic N contents to meet the N requirement for the wheat, especially during its late growth stage. In the meantime, the fertilizer N use efficiency was improved by 58.2%-101.2%. Polymer-coated urea produced better wheat yield and higher fertilizer N use efficiency, compared with sulfur-coated controlled release urea.

  11. Effects of Controlled Release Fertilizer on the Flag Leaves Senescence in Dry-land Wheat

    Directory of Open Access Journals (Sweden)

    Dandan Liu

    2013-05-01

    Full Text Available In order to select a reasonable controlled release fertilizer application method to slow down the senescence of flag leaf in dry-land wheat. The effects of controlled release fertilizer on soluble protein content, MDA content, the Catalase (CAT activity, the Superoxide Dismutase (SOD activity on the flag leaves senescence in dry-land wheat had been studied in the open field with the variety wheat Jimai22. The results indicated that, the combination application of controlled release fertilizer with conventional complex fertilizer on wheat was more conducive to the promotion of the soluble protein synthesis and it controlled the increasing of MDA content in flag leaf more effectively than the application of conventional complex fertilizer or controlled-release fertilizer alone on wheat. And it was more conductive to control or delay the process of flag leaf senescence with better maintenance of the SOD activity. The treatments in application of controlled release fertilization alone were conducive to these treatments with conventional complex fertilizer alone. Among these treatments, T6 was the best fertilization method with the lowest flag leaf senescence speed.

  12. Potential impact of fertilization practices on human dietary intake of dioxins in Belgium.

    Science.gov (United States)

    Dumortier, P; Elskens, M; Focant, J F; Goeyens, L; Vandermeiren, K; Pussemier, L

    2012-04-15

    Dioxins can enter the food chain at any stage, including crop fertilization. Therefore, we developed a simple method for estimating the introduction of dioxins in the food chain according to various fertilization practices. Using dioxin's contamination data taken from the literature, we estimated that fertilization accounts for approximately 20% of the dioxin inputs on agricultural soils at country scale. For the estimations at the field scale, 6 fertilization scenarios were considered: sludge, compost, digestate, manure, mineral fertilizers, and a common fertilization scenario that corresponds to an average situation in Belgium and combines mineral and organic fertilizers. According to our first estimations, mineral fertilizers, common fertilization practices or manure bring less than 1 ng TEQ/m² while atmospheric deposition or digestate bring between 1 and 3 ng TEQ/m² and sludge or compost bring more than 3 ng TEQ/m². The use of solid fertilizers could potentially increase the dioxin levels in the 30 cm agricultural soil layer by 0 to ~1.5% per year (up to ~9% for the 5 cm thick surface layer). For animals, the increase in dioxin ingestion linked to the fertilization practices is lower than 1% for most scenarios with the exception of the compost scenario. Increases in human dietary intake of dioxin are estimated to be lower than 1% for conventional rearing methods (i.e. grazing animals are reared outdoor while pigs and poultry are reared indoor). Spraying liquid fertilizers on meadows and fodder crops, even if very limited in practice, deserves much more attention because this application method could theoretically lead to higher dioxin's intake by livestock (from 6 to ~300%). Considering an average half-life of dioxins in soils of 13 years, it appears that the risks of accumulation in soils and in the food chain are negligible for the various fertilization scenarios.

  13. Effects of a controlled-release fertilizer on yield, nutrient uptake, and fertilizer usage efficiency in early ripening rapeseed (Brassica napus L.)*

    Science.gov (United States)

    Tian, Chang; Zhou, Xuan; Liu, Qiang; Peng, Jian-wei; Wang, Wen-ming; Zhang, Zhen-hua; Yang, Yong; Song, Hai-xing; Guan, Chun-yun

    2016-01-01

    Background: Nitrogen (N), phosphorous (P), and potassium (K) are critical nutrient elements necessary for crop plant growth and development. However, excessive inputs will lead to inefficient usage and cause excessive nutrient losses in the field environment, and also adversely affect the soil, water and air quality, human health, and biodiversity. Methods: Field experiments were conducted to study the effects of controlled-release fertilizer (CRF) on seed yield, plant growth, nutrient uptake, and fertilizer usage efficiency for early ripening rapeseed (Xiangzayou 1613) in the red-yellow soil of southern China during 2011–2013. It was grown using a soluble fertilizer (SF) and the same amounts of CRF, such as SF1/CRF1 (3750 kg/hm2), SF2/CRF2 (3000 kg/hm2), SF3/CRF3 (2250 kg/hm2), SF4/CRF4 (1500 kg/hm2), SF5/CRF5 (750 kg/hm2), and also using no fertilizer (CK). Results: CRF gave higher seed yields than SF in both seasons by 14.51%. CRF4 and SF3 in each group achieved maximum seed yield (2066.97 and 1844.50 kg/hm2, respectively), followed by CRF3 (1929.97 kg/hm2) and SF4 (1839.40 kg/hm2). There were no significant differences in seed yield among CK, SF1, and CRF1 (P>0.05). CRF4 had the highest profit (7126.4 CNY/hm2) and showed an increase of 12.37% in seed yield, and it decreased by 11.01% in unit fertilizer rate compared with SF4. The branch number, pod number, and dry matter weight compared with SF increased significantly under the fertilization of CRF (Pfertilizer rate at maturity, and the N, P, and K usage efficiency decreased with increasing the fertilizer rate. The N, P, and K uptakes and usage efficiencies of the CRF were significantly higher than those of SF (Pefficiency of CRF increased by an average of 13.66% and 9.74 percentage points, respectively, compared to SF. In conclusion, CRF significantly promoted the growth of rapeseed with using total N as the base fertilizer, by providing sufficient N in the later growth stages, and last by reducing the

  14. The Effects of Different Amounts of Controlled Release Fertilizer on the Root Growth and the Filling Rate in Winter Wheat

    OpenAIRE

    Meng Li; Jingtian Yang; Liyuan Yan; Yan Shi

    2014-01-01

    In order to increase the fertilizer use efficiency and yield in winter wheat, the effects of controlled release fertilizer on the root growth and the filling rate in winter wheat by applying different amounts of controlled release fertilizer had been studied in open field. The results indicated that conventional complex fertilizer and controlled release fertilizer could cause corresponding changes of the wheat root activity, dry root weight, root-shoot ratio and filling rate, but the fertiliz...

  15. The Effects of Different Amounts of Controlled Release Fertilizer on the Root Growth and the Filling Rate in Winter Wheat

    OpenAIRE

    Meng Li; Jingtian Yang; Liyuan Yan; Yan Shi

    2014-01-01

    In order to increase the fertilizer use efficiency and yield in winter wheat, the effects of controlled release fertilizer on the root growth and the filling rate in winter wheat by applying different amounts of controlled release fertilizer had been studied in open field. The results indicated that conventional complex fertilizer and controlled release fertilizer could cause corresponding changes of the wheat root activity, dry root weight, root-shoot ratio and filling rate, but the fertiliz...

  16. [Fate and balance of bulk blending controlled release fertilizer nitrogen under continuous cropping of mustard].

    Science.gov (United States)

    Zhang, Pan-Pan; Fan, Xiao-Lin

    2012-10-01

    Under the conditions of applying water soluble fertilizer and its bulk blending with controlled release fertilizer (BB-CRF), and by using micro-lysimeter, this paper quantitatively studied the nitrogen (N) uptake by mustard, the soil N losses from N2O emission, leaching and others, and the N residual in soil in three rotations of continuously cropped mustard. In the treatment of BB-CRF with 25% of controlled release nitrogen, the N uptake by mustard increased with rotations, and the yield by the end of the experiment was significantly higher than that in the treatment of water soluble fertilizer. The cumulated N2O emission loss and the N leaching loss were obviously higher in treatment water soluble fertilizer than in treatment BB-CRF. NO3(-)-N was the primary form of N in the leachate. In relative to water soluble fertilizer, BB-CRF altered the fates of fertilizer nitrogen, i.e., the N uptake by mustard and the N residual in soil increased by 75.4% and 76.0%, and the N leaching loss and other apparent N losses decreased by 27.1% and 66.3%, respectively. The application of BB-CRF could be an effective way to reduce the various losses of fertilizer N while increase the fertilizer N use efficiency, and the controlled release fertilizer is the environmentally friendly fertilizer with the property of high N use efficiency.

  17. Phosphorus fertilization for rice and control of environmental pollution problems.

    Science.gov (United States)

    Choudhury, A T M A; Kennedy, I R; Ahmed, M F; Kecskés, M L

    2007-07-01

    Aim of this study to review information on various aspects of P fertilization in rice i.e., P nutrition of rice, P response of rice plant, P availability in rice soils and P adsorption in rice soils for better understanding of P fertilization in rice culture. A substantial portion of the applied P along with the soil P is lost from rice fields to water bodies causing environmental pollution problems through eutrophication. These pollution problems can be minimized by using proper source of P as fertilizer, proper timing and methods of P fertilizer application, soil P management, transport management, use of plant growth promoting microorganisms which helps in efficient use of P by crops and use of green manure crops which improves soil fertility as well as helps in efficient use of P by crops.

  18. Use of Controlled Release Fertilizer for Increasing N Efficiency of Direct Seeding Rice

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Field trials on a silt-loamy paddy soil derived from shallow-sea deposit in direct seeding rice fields were conducted in Zhejiang, China, in 1996 to compare N efficiency of controlled release fertilizers (LP fertilizers) with the conventional urea. Six treatments including CK (no N fertilizer), conventional urea and different types of LP fertilizers at different rates were designed for two succeeding crops of early and late rice. A blend of different types of LP fertilizers as a single preplant "co-situs" application released N in a rate and amount synchronizing with uptake pattern of direct seeding rice. A single preplant application of the LP fertilizers could meet the N requirement of rice for the whole growth period without need of topdressing. Using LP fertilizer blends, equivalent grain yields could be maintained even if the N fertilization rates were reduced by 25%~50% compared with the conventional urea. Agronomic efficiency of the LP fertilizers was 13.6%~86.4% higher than that of the conventional urea in early rice and 100%~164.1% in late rice, depending on the amounts of the LP fertilizers applied. N fertilizer recovery rate increased from 27.4% for the conventional application of urea to 41.7%~54.1% for the single preplant "co-situs" application of the LP fertilizers. Use of the LP fertilizers was promising if the increase in production costs due to the high LP fertilizer prices could be compensated by increase in yield and N efficiency, reduction in labor costs and improvement in environment.

  19. Nutrients Release from a Novel Gel-Based Slow/Controlled Release Fertilizer

    OpenAIRE

    Ding, H.; Y. S. Zhang; Li, W. H.; Zheng, X. Z.; Wang, M. K.; Tang, L. N.; Chen, D. L.

    2016-01-01

    A novel gel-based slow/controlled release fertilizer (G-CRF) was developed, which was produced by combining various natural, seminatural, and/or synthetic organic macromolecule materials and natural inorganic mineral with conventional NPK fertilizers. Its nutrient release characteristics were studied to compare with conventional fertilizers through the soil column leaching method. The influences of soil factors, including temperature, pH, water, and nutrient contents in the G-CRF on nutrient ...

  20. Encapsulated Urea-Kaolinite Nanocomposite for Controlled Release Fertilizer Formulations

    Directory of Open Access Journals (Sweden)

    Siafu Ibahati Sempeho

    2015-01-01

    Full Text Available Urea controlled release fertilizer (CRF was prepared via kaolinite intercalation followed by gum arabic encapsulation in an attempt to reduce its severe losses associated with dissolution, hydrolysis, and diffusion. Following the beneficiation, the nonkaolinite fraction decreased from 39.58% to 0.36% whereas the kaolinite fraction increased from 60.42% to 99.64%. The X-ray diffractions showed that kaolinite was a major phase with FCC Bravais crystal lattice with particle sizes ranging between 14.6 nm and 92.5 nm. The particle size varied with intercalation ratios with methanol intercalated kaolinite > DMSO-kaolinite > urea-kaolinite (KPDMU. Following intercalation, SEM analysis revealed a change of order from thick compact overlapping euhedral pseudohexagonal platelets to irregular booklets which later transformed to vermiform morphology and dispersed euhedral pseudohexagonal platelets. Besides, dispersed euhedral pseudohexagonal platelets were seen to coexist with blocky-vermicular booklets. In addition, a unique brain-form agglomeration which transformed into roundish particles mart was observed after encapsulation. The nanocomposites decomposed between 48 and 600°C. Release profiles showed that 100% of urea was released in 97 hours from KPDMU while 87% was released in 150 hours from the encapsulated nanocomposite. The findings established that it is possible to use Pugu kaolinite and gum arabic biopolymer to prepare urea CRF formulations.

  1. Effects of Control Release Fertilizers on Nutrient Leaching, Palm Growth and Production Cost

    OpenAIRE

    Pushpa Soti; Angie Fleurissaint; Stewart Reed; Krish Jayachandran

    2015-01-01

    Objective of this study was to evaluate the effect of different controlled release fertilizer technologies on nutrient leaching and plant growth parameters of two palm species, Chinese Fan (Livistona chinensis) and Queen (Syagrus romanzoffiana). We compared Nutri-Pak (12-4-12 controlled release packet) and Harrell’s (12-4-12 controlled release polymer coated urea) against Atlantic (8-4-12 controlled release polymer coated urea, coated sulfate of potash), the most commonly used palm fertilize...

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

    Directory of Open Access Journals (Sweden)

    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.

  3. The Supply of Birth Control Methods, Education, and Fertility: Evidence from Romania

    Science.gov (United States)

    Pop-Eleches, Cristian

    2010-01-01

    This paper investigates the effect of the supply of birth control methods on fertility behavior by examining Romania's 23-year period of pronatalist policies. Following the lifting of the restrictions in 1989 the immediate decrease in fertility was 30 percent. Women who spent most of their reproductive years under the restrictive regime…

  4. The Supply of Birth Control Methods, Education, and Fertility: Evidence from Romania

    Science.gov (United States)

    Pop-Eleches, Cristian

    2010-01-01

    This paper investigates the effect of the supply of birth control methods on fertility behavior by examining Romania's 23-year period of pronatalist policies. Following the lifting of the restrictions in 1989 the immediate decrease in fertility was 30 percent. Women who spent most of their reproductive years under the restrictive regime…

  5. Molecular architecture of the human sperm IZUMO1 and egg JUNO fertilization complex.

    Science.gov (United States)

    Aydin, Halil; Sultana, Azmiri; Li, Sheng; Thavalingam, Annoj; Lee, Jeffrey E

    2016-06-23

    Fertilization is an essential biological process in sexual reproduction and comprises a series of molecular interactions between the sperm and egg. The fusion of the haploid spermatozoon and oocyte is the culminating event in mammalian fertilization, enabling the creation of a new, genetically distinct diploid organism. The merger of two gametes is achieved through a two-step mechanism in which the sperm protein IZUMO1 on the equatorial segment of the acrosome-reacted sperm recognizes its receptor, JUNO, on the egg surface. This recognition is followed by the fusion of the two plasma membranes. IZUMO1 and JUNO proteins are indispensable for fertilization, as constitutive knockdown of either protein results in mice that are healthy but infertile. Despite their central importance in reproductive medicine, the molecular architectures of these proteins and the details of their functional roles in fertilization are not known. Here we present the crystal structures of human IZUMO1 and JUNO in unbound and bound conformations. The human IZUMO1 structure exhibits a distinct boomerang shape and provides structural insights into the IZUMO family of proteins. Human IZUMO1 forms a high-affinity complex with JUNO and undergoes a major conformational change within its N-terminal domain upon binding to the egg-surface receptor. Our results provide insights into the molecular basis of sperm-egg recognition, cross-species fertilization, and the barrier to polyspermy, thereby promising benefits for the rational development of non-hormonal contraceptives and fertility treatments for humans and other mammals.

  6. Community perceptions of human excreta as fertilizer in peri-urban agriculture in Ghana.

    Science.gov (United States)

    Mariwah, Simon; Drangert, Jan-Olof

    2011-08-01

    Although human excreta contain the necessary nutrients for plant growth, local authorities in Ghana spend huge sums of money to dispose them as waste. Reusing excreta for agricultural purposes saves expenditure for chemical fertilizers, improves soil fertility, reduces poverty and ensures food security. People's attitudes and perceptions about excreta vary between cultures and even within specific cultures. This study aimed to explore attitudes and perceptions among a peri-urban agricultural community towards sanitized human excreta and its use. The study adopted an exploratory design and collected data from 154 randomly selected households using questionnaires and focus group discussions. It was found that there is a general negative attitude to fresh excreta and the handling of it. However, the residents accept that excreta can be used as fertilizer, but they are not willing to use it on their own crops or consume crops fertilized with excreta. The study recommends open discussions in the community for a successful implementation of ecological sanitation.

  7. A Preliminary Study on Natural Matrix Materials for Controlled Release Nitrogen Fertilizers

    Institute of Scientific and Technical Information of China (English)

    DU Chang-Wen; ZHOU Jian-Min; WANG Huo-Yan; LI Shou-Tian

    2004-01-01

    A controlled release N fertilizer was developed by the carrier method using natural polysaccharides (PS)and urea. The results showed that mixing of PS and urea led to significant control of urea release. When a cross-linker (boric acid or glutaraldehyde) was added, a better control effect was observed. During a 30 min leaching time the nitrogen release rate from the controlled release fertilizer was nearly constant, which was significantly different from normal urea. One of the controlled release mechanisms was related to space resistance from a large molecular structure. Infrared (IR) analysis indicated that interaction of PS with urea was through a hydrogen bond or a covalent bond. These bonds created an α-helix or high molecular network fertilizer carrier system, which was another reason for a controlled nutrient release. Pot experiment showed that nitrogen use efficiency could increase significantly with a carrier fertilizer.

  8. Effects of Controlled Release Fertilizer on the Flag Leaves Senescence in Dry-land Wheat

    OpenAIRE

    Dandan Liu; Yan Shi

    2013-01-01

    In order to select a reasonable controlled release fertilizer application method to slow down the senescence of flag leaf in dry-land wheat. The effects of controlled release fertilizer on soluble protein content, MDA content, the Catalase (CAT) activity, the Superoxide Dismutase (SOD) activity on the flag leaves senescence in dry-land wheat had been studied in the open field with the variety wheat Jimai22. The results indicated that, the combination application of controlled release fertiliz...

  9. Effects of Controlled Release Fertilizer on the Flag Leaves Senescence in Dry-land Wheat

    OpenAIRE

    Dandan Liu; Yan Shi

    2013-01-01

    In order to select a reasonable controlled release fertilizer application method to slow down the senescence of flag leaf in dry-land wheat. The effects of controlled release fertilizer on soluble protein content, MDA content, the Catalase (CAT) activity, the Superoxide Dismutase (SOD) activity on the flag leaves senescence in dry-land wheat had been studied in the open field with the variety wheat Jimai22. The results indicated that, the combination application of controlled release fertiliz...

  10. CONTROL OF SOME PATHOGENS BY USING SPECIAL FOLIAR FERTILIZERS

    Directory of Open Access Journals (Sweden)

    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.

  11. Human Menopausal Gonadotropin versus Recombinant FSH in Polycystic Ovary Syndrome Patients Undergoing In Vitro Fertilization

    Directory of Open Access Journals (Sweden)

    Sertac Batioglu

    2013-01-01

    Full Text Available Background: We aimed to compare human menopausal gonadotropin (hMG and recombinantfollicle-stimulating hormone (r FSH with respect to clinical outcomes and the development ofovarian hyperstimulation syndrome (OHSS for patients with polycystic ovary syndrome (PCOStreated with in vitro fertilization (IVF.Materials and Methods: This prospective randomized controlled trial included a total of 80 womenwith PCOS. Of these, 38 were randomized to receive treatment with hMG and 42 with rFSH usinga long gonadotropin releasing hormone (GnRH analogue protocol. Outcome measures were cyclecharacteristics, pregnancy rates, the need for coasting, and OHSS rates.Results: In the hMG group we observed a significantly lower peak estradiol (E2 level (p=0.02,fewer intermediate-sized follicles (p=0.001, lower number of oocytes retrieved (p=0.002 andmetaphase II (MII oocytes (p=0.003. However, there were no significant differences between thegroups in the number of fertilized oocytes, fertilization rates, top quality embryo counts, and thenumber of transferred embryos. There was no difference in pregnancy rates between the groups.OHSS occurred in 11.9% of the rFSH group patients, whereas no OHSS developed in the hMGgroup. Coasting requirements were lower in the hMG group (19.2% vs. 48.9%, p=0.013.Conclusion: Ovarian stimulation with hMG and rFSH provides similar clinical pregnancy rates inPCOS patients treated with a long GnRH agonist protocol in IVF cycles. hMG stimulation appearsto be associated with a lower rate of OHSS and decreased coasting requirements (RegistrationNumber: NCT01365936.

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

    Science.gov (United States)

    Huang, Z

    1991-04-01

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

  13. [Control of fertilization by self-incompatibility mechanisms].

    Science.gov (United States)

    Fobis-Loisy, Isabelle; Gaude, Thierry

    2010-01-01

    Flowering plants (angiosperms) are the most prevalent and evolutionarily advanced group of plants. Reproductive strategies that promote cross-fertilization have played an essential role in the success of angiosperms as they contribute to genetic variability among plant species. A major genetic barrier to self-fertilization is self-incompatibility (SI), which allows female reproductive cells to discriminate between self- and non-self pollen and specifically reject self-pollen. In this review, we describe three SI mechanisms showing that different flowering plant families use distinct molecules for recognition of self as well as diverse biochemical pathways to arrest pollen tube growth.

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

    Science.gov (United States)

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

    2014-01-01

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

  15. [Effects of slow/controlled release fertilizers on the growth and nutrient use efficiency of pepper].

    Science.gov (United States)

    Tang, Shuan-Hu; Zhang, Fa-Bao; Huang, Xu; Chen, Jian-Sheng; Xu, Pei-Zhi

    2008-05-01

    Pot trails were conducted from 2003 to 2005 to study the effects of slow/controlled release fertilizers on the growth and nutrient use efficiency of pepper. The results indicated that in comparison with conventional splitting fertilization (T1), basal application of polymer-coated controlled release fertilizer (T2) enhanced the single fruit mass and vitamin C concentration, improved the root activity, and increased the fruit yield by 8.4%, but no significant effect was observed on the dissoluble sugar concentration in fruit. NH4MgPO4-coated controlled release fertilizer (T3) increased the dissoluble sugar concentration by 5.67%, but had less effect on single fruit mass and vitamin C concentration. Under the application of T3, the root system had a vigorous growth at early stages but became infirm at later stages, resulting in a lower yield. Comparing with T1, the application of 3 slow release fertilizers increased the dissoluble sugar concentration in fruit, enhanced the root activity, but had less effect on the yield. All test slow/controlled release fertilizers increased the use efficiency of N, P, and K significantly, with an exception for T2 which increased the use efficiency of N and K but decreased that of P. It was demonstrated that an appropriate application of slow/controlled release fertilizers could enhance pepper' s root activity and improve nutrient use efficiency.

  16. Application of human growth hormone to patients with polycystic ovary syndrome during in vitro fertilization

    Institute of Scientific and Technical Information of China (English)

    An Jin-xia; Liu Zhen

    2011-01-01

    Objective:To observe the effect of applying human growth hormone during in vitro fertilization to patients with polycystic ovary syndrome (PCOS)Methods:One hundred and twenty-one cycles of in vitro fertilization and embryo transfer in PCOS patients with anovulation from Dec.2008 to Nov.2010 were studied retrospectively.Of these 121 cycles,48 were with treatment of growth hormone (GH group),73 without GH treatment (control group).The dose of gonadotropin (Gn),the number of retrieved oocytes,good-quality embryo rate,implantation rate,frozen embryo rate,and pregnancy rate were compared.Results:The dosage of Gn was slightly higher in GH group than that in control group (29.18±8.33 vs.23.43±8.68 ampoullas,4U/ampoulla) and the number of retrieved oocytes in GH group were slightly less than that in control group (10.73±6.0vs.14.0±8.57),but there were no significant differences (P>0.05).The good-quality embryo rate (59.1% vs.33.3%),frozen embryo rate (87.5% vs.58.9%),pregnancy rate (56.5% vs.35.3 % ) and implantation rate (35.3 % vs.20.4 % ) in GH group were all significantly higher than those in control group (P<0.05).Conclusion:Early usage of GH in the ovarian hyperstimulation in PCOS patients could significantly improve good-quality embryo rate,implantation rate and pregnancy rate.

  17. The effect of the culture vessel and insemination method on the in vitro fertilization and development of human oocytes

    OpenAIRE

    Boone, William R.; Johnson, Jane E.

    1997-01-01

    Our laboratory has corroborated previously published work demonstrating that tissue culture tubes and microdrops perform equally well for in vitro fertilization and culture of human oocytes and embryos.

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

    Science.gov (United States)

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

    2016-01-01

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

  19. Comparison of serum vitamin D between fertile and infertile men in a vitamin D deficient endemic area: a case-control study.

    Science.gov (United States)

    Akhavizadegan, Hamed; Karbakhsh, Mojgan

    2017-06-26

    The aim of this study was to compare serum vitamin D between fertile and infertile men in endemic area of vitamin D deficiency. The role of vitamin D in all aspects of human health has attracted a great interest. Vitamin D effect on female fertility and to a lesser extent in men is under investigation. Previous researchers have found meaningful positive relationship between semen quality and serum vitamin D level. However, in endemic area of vitamin D deficiency, this effect is under question. Serum 25-OH-Vitamin D was compared between infertile male patients and fertile control group.Infertile cases were from patients of our infertility clinic and fertile controls from healthy cases with at least one child below 5 years of age.SPSS version 19 was used for statistical analysis (Kolmogorov-Smirnov test and Mann-Whitney test). Between 116 fertile and 114 infertile men who entered the study, serum level of 20 was a critical point, which patients with upper serum level had significantly better spermogram. In addition to it, even in vitamin D deficient patients and controls, fertile controls had higher serum vitamin D. There is a positive correlation between serum level of vitamin D and spermogram quality, even in vitamin D deficient areas. Fertile people have a higher level of serum vitamin D in comparison to infertile patient in aforementioned areas.

  20. Controlled-release NPK fertilizer encapsulated by polymeric membranes.

    Science.gov (United States)

    Jarosiewicz, Anna; Tomaszewska, Maria

    2003-01-15

    The commercial granular fertilizer NPK6-20-30 was coated using polysulfone (PSF), polyacrylonitrile (PAN), and cellulose acetate (CA). The coatings were formed from the polymer solutions by the phase inversion technique. Measurements of the thickness and porosity of the prepared coatings and a microphotographic observation of the coatings were performed. The physical properties of the coatings influence the release rate of macronutrients which are present in the core of the coated fertilizer. In the case of PAN coating with 60.45% porosity, prepared from a 16% polymer solution, 100% of NH(4)(+) and P(2)O(5) was released after 4 h of test and 99.7% of K(+) after 5 h of test, whereas in the case of coating with 48.8% porosity, 31.8% of NH(4)(+), 16.7% of P(2)O(5), and 11.6% of K(+) was released after 5 h. In all experiments, different selectivities of the coatings in terms of the release of components were observed. The release of potassium through the coatings made of PSF and PAN was the slowest. The same tendency was observed for the release of nitrogen through a coating of CA. The release of fertilizer active components was the slowest in the case of PSF. The lowest porosity coating was prepared from the 18% PSF solution.

  1. [Effects of applying controlled-release compound fertilizer on Platycodon grandiflorum growth].

    Science.gov (United States)

    Zhu, Li-xiang; Wang, Jian-hua

    2010-09-01

    A pot experiment was conducted in 2008 to study the effects of applying controlled-release compound fertilizer (N:P2O5:K2O = 14:14:14) on the growth of Platycodon grandiflorum in the medicinal herbal farm of Shandong Agricultural University. Comparing with the application of common compound fertilizer (N:P2O5: K2O=15: 15: 15), applying equivalent amount of the controlled-release fertilizer increased the leaf chlorophyll content, root volume, root activity, and root diameter of P. grandiflorum at the late growth stage, but decreased the root length. When the N application rate was 0.24 and 0.32 g x kg(-1) soil, applying the controlled-release compound fertilizer increased the root yield by 26.78% and 22.50%, and the root soluble sugar, protein, and total saponin contents by 9.77% and 6.99%, 11.38% and 2.20%, and 8.85% and 5.47%, respectively, compared with applying the common compound fertilizer. More nitrogen application made the root soluble sugar content decreased but the total saponin content increased. Under our experimental condition, applying the controlled-release compound fertilizer with an application rate of 0.24 g N x kg(-1) soil could obtain the best effect for P. grandiflorum.

  2. The Effect of Fibronectin on the Fertilization Capacity of Human Spermatozoa

    Institute of Scientific and Technical Information of China (English)

    许复华; 崔晓; 杨抚华

    1996-01-01

    Fibronectin (Fn) is a major molecular glycoprotein that is known to play an important role in many systems involved in cell-to-cell interation and cell-to-matrix adhesion. We initially studied the effect of Fn on the fertilization capacity of human spermatozoa with a penetration test in vitro. Following co-incubation of Fn in a heterologous system (human spermatozoa and zona-free golden hamster oocytes ), we have noted a significant decrease in the rate of sperm penetration into oolemma at 2.8 μg Fn/ml,and a complete inhibition of fertilization at 15 μg Fn/ml. Besides, we noted a specific increase in the penetration rate during the co incubation of anti-Fn-serum in a heterologous system. These results suggest that extrinsic Fn binds with the Fn-receptor in the oolemma, thereby, competitively inhibiting fertilization.

  3. Ion channels that control fertility in mammalian spermatozoa.

    Science.gov (United States)

    Navarro, Betsy; Kirichok, Yuriy; Chung, Jean-Ju; Clapham, David E

    2008-01-01

    Whole-cell voltage clamp of mammalian spermatozoa was first achieved in 2006. This technical advance, combined with genetic deletion strategies, makes unambiguous identification of sperm ion channel currents possible. This review summarizes the ion channel currents that have been directly measured in mammalian sperm, and their physiological roles in fertilization. The predominant currents are a Ca2+-selective current requiring expression of the 4 mCatSper genes, and a rectifying K+ current with properties most similar to mSlo3. Intracellular alkalinization activates both channels and induces hyperactivated motility.

  4. Cross-species fertilization: the hamster egg receptor, Juno, binds the human sperm ligand, Izumo1.

    Science.gov (United States)

    Bianchi, Enrica; Wright, Gavin J

    2015-02-05

    Fertilization is the culminating event in sexual reproduction and requires the recognition and fusion of the haploid sperm and egg to form a new diploid organism. Specificity in these recognition events is one reason why sperm and eggs from different species are not normally compatible. One notable exception is the unusual ability of zona-free eggs from the Syrian golden hamster (Mesocricetus auratus) to recognize and fuse with human sperm, a phenomenon that has been exploited to assess sperm quality in assisted fertility treatments. Following our recent finding that the interaction between the sperm and egg recognition receptors Izumo1 and Juno is essential for fertilization, we now demonstrate concordance between the ability of Izumo1 and Juno from different species to interact, and the ability of their isolated gametes to cross-fertilize each other in vitro. In particular, we show that Juno from the golden hamster can directly interact with human Izumo1. These data suggest that the interaction between Izumo1 and Juno plays an important role in cross-species gamete recognition, and may inform the development of improved prognostic tests that do not require the use of animals to guide the most appropriate fertility treatment for infertile couples.

  5. CD9 Expression by Human Granulosa Cells and Platelets as a Predictor of Fertilization Success during IVF

    Directory of Open Access Journals (Sweden)

    Carolyn R. Jaslow

    2010-01-01

    Full Text Available Objective. To determine whether CD9 expression on human granulosa cells (GCs and platelets could predict the success of conventional fertilization of human oocytes during in vitro fertilization (IVF. Methods. Thirty women undergoing IVF for nonmale factor infertility participated. Platelets from venous blood and GCs separated from retrieved oocytes were prepared for immunofluorescence. Flow cytometry quantified the percent of GCs expressing CD9, and CD9 surface density on GCs and platelets. Fertilization rate was determined for the total number of oocytes, and the number of mature oocytes per patient. Correlations tested for significant relationships (P<.05 between fertilization rates and CD9 expression. Results. CD9 surface density on human GCs is inversely correlated with fertilization rate of oocytes (P=.04, but the relationship was weak. Conclusion. More studies are needed to determine if CD9 expression on GCs would be useful for predicting conventional fertilization success during IVF.

  6. [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.

  7. The evolutionary approach to understand human low fertility phenomenon

    Science.gov (United States)

    Cernak, Jozef

    2017-05-01

    Is it possible to reverse the low total fertility rate (TFR) in the developed world? Using a hypothetical model of population we have analysed the decline of the TFR which have took place in the background of ongoing global economic changes, and a liberalization process after the end of the Cold War. These phenomena have affected more that 110 millions of inhabitants of Central Europe and the Baltics and approximately 80 millions of inhabitants in Germany. The model has features of complex and evolving system of interacting individuals, and it enables to investigate a broad spectrum of input factors on individual decisions to limit the offspring. In the case of the TFR 2.1. The changes should stimulate more uniform spatial distribution of wealth, capital and usage. They will increase a number of self-sufficient and cooperative territories, to decrease the income inequality, to decrease labour and social mobilities. Societies should investigate the impacts of economic regulations and actions on the TFR trends in advance and take into account a biological nature of women more responsible.

  8. 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.

  9. Effects of Control Release Fertilizers on Nutrient Leaching, Palm Growth and Production Cost

    Directory of Open Access Journals (Sweden)

    Pushpa Soti

    2015-11-01

    Full Text Available Objective of this study was to evaluate the effect of different controlled release fertilizer technologies on nutrient leaching and plant growth parameters of two palm species, Chinese Fan (Livistona chinensis and Queen (Syagrus romanzoffiana. We compared Nutri-Pak (12-4-12 controlled release packet and Harrell’s (12-4-12 controlled release polymer coated urea against Atlantic (8-4-12 controlled release polymer coated urea, coated sulfate of potash, the most commonly used palm fertilizer in South Florida. Plants were grown in 25 cm (11 L pots under 70% shade, watered weekly, with pest and weed control done as required. Plant growth parameters: number of leaves, leaf length and width, and basal diameter, were measured every two months. Leachate was collected weekly after irrigation and a two-month composite sample was analyzed for nutrient concentrations. There was no difference in the growth parameters among the three fertilizers for Chinese Fan plants. However for Queen, Atlantic and Harrell’s had significantly thicker basal diameter than Nutri-Pak. Significant difference in the concentration of nutrients in the leachate was observed among the fertilizer types. Throughout the study period, Nutri-Pak had a lower concentration of nutrients in the leachate than Atlantic and Harrell’s. Our research indicates that Nutri-Pak control release fertilizer is comparable to other commercial fertilizers in Chinese Fan growth, but the larger Queen palms likely require an additional packet. Nutri-Pak fertilizer resulted in less nutrient leaching and could be a better environmental choice.

  10. Preparation and characterization of controlled-release fertilizers coated with marine polysaccharide derivatives

    Science.gov (United States)

    Wang, Jing; Liu, Song; Qin, Yukun; Chen, Xiaolin; Xing, Rong'e.; Yu, Huahua; Li, Kecheng; Li, Pengcheng

    2017-09-01

    Encapsulation of water-soluble nitrogen fertilizers by membranes can be used to control the release of nutrients to maximize the fertilization effect and reduce environmental pollution. In this research, we formulated a new double-coated controlled-release fertilizer (CRF) by using food-grade microcrystalline wax (MW) and marine polysaccharide derivatives (calcium alginate and chitosan-glutaraldehyde copolymer). The pellets of water-soluble nitrogen fertilizer were coated with the marine polysaccharide derivatives and MW. A convenient and eco-friendly method was used to prepare the CRF. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) were used to characterize the morphology and composition of the products. The nitrogen-release properties were determined in water using UV-Vis spectrophotometry. The controlled-release properties of the fertilizer were improved dramatically after coating with MW and the marine polysaccharide derivatives. The results show that the double-coated CRFs can release nitrogen in a controlled manner, have excellent controlled-release features, and meet the European Standard for CRFs.

  11. Preparation and characterization of controlled-release fertilizers coated with marine polysaccharide derivatives

    Science.gov (United States)

    Wang, Jing; Liu, Song; Qin, Yukun; Chen, Xiaolin; Xing, Rong'e.; Yu, Huahua; Li, Kecheng; Li, Pengcheng

    2016-10-01

    Encapsulation of water-soluble nitrogen fertilizers by membranes can be used to control the release of nutrients to maximize the fertilization effect and reduce environmental pollution. In this research, we formulated a new double-coated controlled-release fertilizer (CRF) by using food-grade microcrystalline wax (MW) and marine polysaccharide derivatives (calcium alginate and chitosan-glutaraldehyde copolymer). The pellets of water-soluble nitrogen fertilizer were coated with the marine polysaccharide derivatives and MW. A convenient and eco-friendly method was used to prepare the CRF. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) were used to characterize the morphology and composition of the products. The nitrogen-release properties were determined in water using UV-Vis spectrophotometry. The controlled-release properties of the fertilizer were improved dramatically after coating with MW and the marine polysaccharide derivatives. The results show that the double-coated CRFs can release nitrogen in a controlled manner, have excellent controlled-release features, and meet the European Standard for CRFs.

  12. Cryopreservation of human embryos and its contribution to in vitro fertilization success rates.

    Science.gov (United States)

    Wong, Kai Mee; Mastenbroek, Sebastiaan; Repping, Sjoerd

    2014-07-01

    Cryopreservation of human embryos is now a routine procedure in assisted reproductive technologies laboratories. There is no consensus on the superiority of any protocol, and substantial differences exist among centers in day of embryo cryopreservation, freezing method, selection criteria for which embryos to freeze, method of embryo thawing, and endometrial preparation for transfer of frozen-thawed embryos. In the past decade, the number of frozen-thawed embryo transfer cycles per started in vitro fertilization (IVF) cycle increased steadily, and at the same time the percentage of frozen-thawed embryo transfers that resulted in live births increased. Currently, cryopreservation of human embryos is more important than ever for the cumulative pregnancy rate after IVF. Interestingly, success rates after frozen-thawed embryo transfer are now nearing the success rates of fresh embryo transfer. This supports the hypothesis of so called freeze-all strategies in IVF, in which all embryos are frozen and no fresh transfer is conducted, to optimize success rates. High-quality randomized controlled trials should be pursued to find out which cryopreservation protocol is best and whether the time has come to completely abandon fresh transfers.

  13. Concealed fertility and extended female sexuality in a non-human primate (Macaca assamensis.

    Directory of Open Access Journals (Sweden)

    Ines Fürtbauer

    Full Text Available In numerous primates living in mixed-sex groups, females display probabilistic cues of fertility to simultaneously concentrate paternity to dominant males while diluting it amongst others as a means to reduce the risk of infanticide and to increase male care for offspring. A few species, however, lack these cues and potentially conceal fertility from males; yet, to date, little is known about mating patterns and their underlying proximate mechanisms in such species. Here, we investigated mating activity and sexual consortships relative to female reproductive state in wild Assamese macaques (Macaca assamensis, a species where females lack prominent anogenital swellings and copulation calls. During two mating seasons (2837 contact hours we recorded sexual and social behaviors, sexual consortships, and collected 1178 fecal samples (n = 15 females which were analyzed for progestogen concentrations to assess female reproductive state and to determine the timing of ovulation and conception. Although mostly conceiving in their first ovarian cycle, females were sexually receptive throughout the entire 4-month mating season, and within-cycle mating frequencies were not increased during fertile phases. Dominant males did not monopolize fertile matings, and consortships by high-ranking males lasted for long periods, which were not exclusively linked to female fertile phases. Furthermore, females copulated promiscuously but not randomly, i.e. for almost every female, matings were concentrated to a certain male, irrespective of male rank. Collectively, we demonstrate that fertility is undisclosed to males. The extreme extended female sexuality facilitated by concealed fertility may allow females to create differentiated mating relationships within a promiscuous mating system. Our study provides important new insight into the plasticity of female sexuality in non-human primates.

  14. Concealed Fertility and Extended Female Sexuality in a Non-Human Primate (Macaca assamensis)

    Science.gov (United States)

    Fürtbauer, Ines; Heistermann, Michael; Schülke, Oliver; Ostner, Julia

    2011-01-01

    In numerous primates living in mixed-sex groups, females display probabilistic cues of fertility to simultaneously concentrate paternity to dominant males while diluting it amongst others as a means to reduce the risk of infanticide and to increase male care for offspring. A few species, however, lack these cues and potentially conceal fertility from males; yet, to date, little is known about mating patterns and their underlying proximate mechanisms in such species. Here, we investigated mating activity and sexual consortships relative to female reproductive state in wild Assamese macaques (Macaca assamensis), a species where females lack prominent anogenital swellings and copulation calls. During two mating seasons (2837 contact hours) we recorded sexual and social behaviors, sexual consortships, and collected 1178 fecal samples (n = 15 females) which were analyzed for progestogen concentrations to assess female reproductive state and to determine the timing of ovulation and conception. Although mostly conceiving in their first ovarian cycle, females were sexually receptive throughout the entire 4-month mating season, and within-cycle mating frequencies were not increased during fertile phases. Dominant males did not monopolize fertile matings, and consortships by high-ranking males lasted for long periods, which were not exclusively linked to female fertile phases. Furthermore, females copulated promiscuously but not randomly, i.e. for almost every female, matings were concentrated to a certain male, irrespective of male rank. Collectively, we demonstrate that fertility is undisclosed to males. The extreme extended female sexuality facilitated by concealed fertility may allow females to create differentiated mating relationships within a promiscuous mating system. Our study provides important new insight into the plasticity of female sexuality in non-human primates. PMID:21853074

  15. Soil fertility controls the size-specific distribution of eukaryotes.

    Science.gov (United States)

    Mulder, Christian

    2010-05-01

    The large range of body-mass values of soil organisms provides a tool to assess the organization of soil ecological communities. Relationships between log-transformed body mass M and log-transformed numerical abundance N of all eukaryotes occurring under organic pastures, mature grasslands, and seminatural heathlands in the Netherlands were investigated. The observed allometry of (M,N) assemblages of below-ground communities strongly reflects the availability of primary macronutrients and essential micronutrients. This log-linear model describes the continuous variation in the allometric slope of animals and fungi along an increasing soil fertility gradient. The aggregate contribution of small invertebrates (M soil explains 72% of these shifts but the nitrogen concentration explains only 36%, with copper and zinc as intermediate predictors (59% and 49%, respectively). Empirical evidence supports common responses of invertebrates to the rates of resource supply and, possibly, to the above-ground primary production of ecosystems.

  16. Human spinal motor control

    DEFF Research Database (Denmark)

    Nielsen, Jens Bo

    2016-01-01

    interneurons and exert a direct (willful) muscle control with the aid of a context-dependent integration of somatosensory and visual information at cortical level. However, spinal networks also play an important role. Sensory feedback through spinal circuitries is integrated with central motor commands...... 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...... and contributes importantly to the muscle activity underlying voluntary movements. Regulation of spinal interneurons is used to switch between motor states such as locomotion (reciprocal innervation) and stance (coactivation pattern). Cortical regulation of presynaptic inhibition of sensory afferents may focus...

  17. Evaluation of Endotoxin in Culture Medium for Human in vitro Fertilization

    Institute of Scientific and Technical Information of China (English)

    Jing LI; Wei-jie ZHU; Wen-hong ZHANG

    2005-01-01

    Objective To determine whether the presence of bacterial endotoxin in the commercial culture media utilized for human in vitro fertilization (IVF), and evaluate the difference in detecting endotoxin in culture medium between the human sperm motility assay and the 2-cell mouse embryo assay.Methods Thirty-six batches of culture media commonly used in IVF laboratories from 3 manufacturers were determined for the presence ofendotoxin before using the medium for the assisted reproductive programs (group A). After being used, 25 specimens among above media were also tested (group B). The chromogenic limulus amoebocyte lysate (LAL) test was used for quantification the content of endotoxin. In addition, the human sperm motility assay was compared with the 2-cell mouse embryo assay to evaluate the difference in detecting endotoxin in culture medium.Results Endotoxin was not detected in group A. However, 2 samples were positive in group B. Sperm did not show significant change in motility in group A during 24 h of incubation when compared with the control (P>0.05). However, in group A the 2-cell embryo development to blastocyst was suppressed in 3 batches of media.Conclusions Regular screening of each batch of culture medium should be performed if possible although there was no evidence of endotoxin contamination in commercially prepared pre-tested media. Culture environment should be stringently controlled in case the medium is polluted. The sensitivity of the sperm motility assay was lower than that of the mouse embryo assay for detecting low levels of endotoxin or toxic compounds in the medium.

  18. Substrates and controlled-release fertilizations on the quality of eucalyptus cuttings

    Directory of Open Access Journals (Sweden)

    Richardson B. G. da Silva

    2014-11-01

    Full Text Available To produce cuttings with quality, the most appropriate nutritional management strategies should be sought to reduce wastage of fertilizer, while accounting for the characteristics of each substrate. This study evaluated the effect of substrates and doses of controlled-release fertilizer on the quality of Eucalyptus grandis Hill ex Maiden x Eucalyptus urophylla S. T. Blake cuttings. The substrates consisted of several mixtures: vermiculite+carbonized rice chaff+coconut fibre (1:1:1; vermiculite+coconut fibre (1:1; and vermiculite+carbonized rice chaff (1:1. These mixtures were added to 2, 4, 6 and 8 kg of controlled-release fertilizer per cubic meter of substrate. The substrates that do not support root development and have lower water retention, independently of the dose of controlled-release fertilizer, reduce the quality of the root system. For substrates with proper values of water retention, such as vermiculite+coconut fibre (1:1 and vermiculite+carbonised rice chaff+coconut fibre (1:1:1, the utilization of dose 2 kg of controlled-release fertilizer to each cubic meter is enough to promote cuttings with greater quality of the root systems and proper heights and stem diameters.

  19. Application of waterborne acrylic emulsions in coated controlled release fertilizer using reacted layer technology

    Institute of Scientific and Technical Information of China (English)

    Yazhen Shen; Cong Zhao; Jianmin Zhou; Changwen Du

    2015-01-01

    Waterborne acrylic emulsions modified with organic siloxanes and aziridine crosslinker were synthesized and applied as coating of controlled release fertilizer. The free films were characterized and the nutrient release pro-files of the coated fertilizers were determined. The results show that methyl silicone oil and methylsilanolate so-dium could not improve water resistance performance and glass transition temperature Tg of coatings, while the firmness is enhanced. Aziridine crosslinker improves the water resistance performance, firmness and Tg. Incorpo-ration of methyl silicone oil and aziridine crosslinker gives an excellent aqueous acrylic emulsion for coated con-trol ed release fertilizer, with the 30-day cumulative nutrient release reduced to 16%and an estimated nutrient release duration over 190 days. Therefore, this waterborne coating is promising to meet the requirements for controlled release of nutrient and environmental protection.

  20. Analytical solution of diffusion model for nutrient release from controlled release fertilizer

    Science.gov (United States)

    Ameenuddin Irfan, Sayed; Razali, Radzuan; KuShaari, KuZilati; Mansor, Nurlidia; Azeem, Babar

    2017-09-01

    An analytical method has been developed to solve the initial value problem which arises from Fick’s diffusion equation encountered in the modelling of the Controlled Release Fertilizers. The proposed analytical solution is developed using the modified Adomian decomposition method. This method does not require the discretization method, reliability and efficiency of this method is more and it also reduces the calculation time. The model has predicted the effect of granule radius and diffusion coefficient on the nutrient release and total release time of Controlled Release Fertilizer. Model has predicted that increase in the radius of granule reduces the release and vice versa in case of diffusion coefficient. Detailed understanding of these parameters helps in improved designing of Controlled Release Fertilizer.

  1. 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

  2. LYZL6, an acidic, bacteriolytic, human sperm-related protein, plays a role in fertilization

    Science.gov (United States)

    Huang, Peng; Li, Wenshu; Yang, Zhifang; Zhang, Ning; Xu, Yixin; Bao, Jianying; Jiang, Deke; Dong, Xianping

    2017-01-01

    Lysozyme-like proteins (LYZLs) belong to the c-type lysozyme/α-lactalbumin family and are selectively expressed in the mammalian male reproductive tract. Two members, human sperm lysozyme-like protein (SLLP) -1 and mouse LYZL4, have been reported to contribute to fertilization but show no bacteriolytic activity. Here, we focused on the possible contribution of LYZL6 to immunity and fertilization. In humans, LYZL6 was selectively expressed by the testis and epididymis and became concentrated on spermatozoa. Native LYZL6 isolated from sperm extracts exhibited bacteriolytic activity against Micrococcus lysodeikticus. Recombinant LYZL6 (rLYZL6) reached its peak activity at pH 5.6 and 15 mM of Na+, and could inhibit the growth of Gram-positive, but not Gram-negative bacteria. Nevertheless, the bacteriolytic activity of rLYZL6 proved to be much lower than that of human lysozyme under physiological conditions. Immunodetection with a specific antiserum localized the LYZL6 protein on the postacrosomal membrane of mature spermatozoa. Immunoneutralization of LYZL6 significantly decreased the numbers of human spermatozoa fused with zona-free hamster eggs in a dose-dependent manner in vitro. Thus, we report here for the first time that LYZL6, an acidic, bacteriolytic and human sperm-related protein, is likely important for fertilization but not for the innate immunity of the male reproductive tract. PMID:28182716

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

    OpenAIRE

    Renato Luis Grisi Macedo; Elainy Botelho Carvalho Pereira; Ailton Vitor Pereira; Nelson Venturin; Antonio Nilson Zamunér Filho

    2012-01-01

    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-r...

  4. [Effects of applying controlled-release fertilizer blended with conventional nitrogen fertilizer on Chinese cabbage yield and quality as well as nitrogen losses].

    Science.gov (United States)

    Yang, Jun-gang; Xu, Kai; Tong, Er-jian; Cao, Bing; Ni, Xiao-hui; Xu, Jun-xiang

    2010-12-01

    An open field experiment was conducted to study the effects of applying controlled-release fertilizer blended with rapidly available chemical N fertilizer on Chinese cabbage yield and quality as well as nitrogen losses, including ammonia volatilization and NO3- -N accumulation and leaching in Beijing suburb. The results showed that a combined application of 2:1 controlled-release fertilizer and urea fertilizer (total N rate 150 kg x hm(-2)) did not induce the reduction of Chinese cabbage yield, and decreased the leaf nitrate and organic acid contents significantly, compared with conventional urea N application (300 kg x hm(-2)), and had no significant difference in the cabbage yield and leaf nitrate content, compared with applying 150 kg x hm(-2) of urea N. The combined application of 2:1 controlled-release fertilizer and urea fertilizer improved the N use efficiency of Chinese cabbage, and reduced the ammonia volatilization and NO3- -N leaching. At harvest, the NO3- -N concentrations in 20-40, 60-80 and 80-100 cm soil layers were significantly lower in the combined application treatment than in urea N treatment.

  5. Do fertility control policies affect health in old age? Evidence from China's one-child experiment.

    Science.gov (United States)

    Islam, Asadul; Smyth, Russell

    2015-05-01

    How do fertility control policies contribute to the welfare of women, and their husbands, particularly as they get older? We consider whether the reduction in fertility resulting from population control policies has had any effect on the health of elderly parents in China. In particular, we examine the influence of this fertility decline, experienced due to China's one-child policy, on several measures of the health of parents in middle and old age. Overall, our results suggest that having fewer children has a positive effect on self-reported parental health but generally no effect on other measures of health. The results also suggest that upstream financial transfers have a positive effect on several measures of parental health.

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

    Science.gov (United States)

    Alvergne, Alexandra; Jokela, Markus; Lummaa, Virpi

    2010-06-29

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

  7. QUANTIFICATION AND LOCALIZATION OF WHEAT GERM AGGLUTININ RECEPTOR ON HUMAN SPERMME MBRANE IN FERTILE AND INFERTILE MALES

    Institute of Scientific and Technical Information of China (English)

    PANZhi-Xing; WANGYi-Fei

    1989-01-01

    It has been proved/n our prcvious study that wheat germ agglutinin (WGA) receptor on human sperm membrane is closely related to male fertility and there exists a significant difference in WGA receptors betweea fertile and infertile mcn. In this report, enzyme linked

  8. 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.

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

    OpenAIRE

    Alvergne, A.; JOKELA, M; Lummaa, V

    2010-01-01

    The existence of interindividual differences in personality traits poses a challenge to evolutionary thinking. Although research on the ultimate consequences of personality differences in nonhuman animals has recently undergone a surge of interest, our understanding of whether and how personality influences reproductive decisions in humans has remained limited and informed primarily by modern societies with low mortality–fertility schedules. Taking an evolutionary approach, we use data from a...

  10. Effects of Controlled Release Fertilizer on the Post-Production Performance of Impatiens Wallerana

    Science.gov (United States)

    Controlled release fertilizers (CRF) in production systems have been known to reduce environmental contamination. However, there is a lot to be explored as per its use in bedding plant production. Bedding plant growers have not adapted CRF use because there is little information about its use and ...

  11. Longevity of controlled release fertilizer influences the growth of bedding Impatiens

    Science.gov (United States)

    Controlled-release fertilizers (CRF) have not been extensively used in floriculture production, perhaps due to lack of grower experience and research-based information with their use in herbaceous plant production. Any information about the correct use of CRF should increase growers’ confidence in ...

  12. Quality control analysis of imported fertilizers used in Ghana: the macronutrients perspective

    Directory of Open Access Journals (Sweden)

    Sheriff Enti-Brown

    2012-03-01

    Full Text Available The main objective of this environmental research was to validate specifications indicated by manufacturers on their fertilizer products. Selected fertilizers types were sampled from five major fertilizer importing companies in Ghana for macronutrient analysis to determine the fertilizer quality. Five analytical techniques including Instrumental Neutron Activation Analysis (INAA, flame photometry, Kjeldahl method for nitrogen analysis and UV-visible spectroscopy were employed to achieve this objective. Two reference materials (IAEA Soil-7 and SRM 1646a Estuarine Sediment were used to validate the quantitative method employed in the INAA. There was generally good agreements (98% and above between the measured values and the certified values for the primary macronutrients nitrogen, phosphorous and potassium (N, P and K. However, same could not be said for secondary macronutrients calcium, magnesium and sulphur (Ca, Mg and S. The secondary macronutrient values measured were compared to standard values from the Ministry of Food and Agriculture (MOFA in cases where they were not certified by the manufacturer. Most of the manufacturers' claims for primary macronutrients were valid. However, most of them fell short of the requirements for secondary macronutrient concentration. There is therefore the need for a good quality control system to undertake periodic quality monitoring of the chemical compositions of fertilizers imported into the country since they may directly or indirectly have impacts on the environment.

  13. 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.

  14. [Effects of controlled release fertilizers on N2O emission from paddy field].

    Science.gov (United States)

    Li, Fangmin; Fan, Xiaolin; Liu, Fang; Wang, Qiang

    2004-11-01

    With close chamber method, this paper studied the effects of controlled release fertilizer (CRF), non-coated compound fertilizer (Com) and conventional urea (CK) on N2O emission from paddy field. The results showed that within 10 days after transplanting, the ammonium and nitrate concentrations in the surface water of the plot treated with CRF were significantly different from those treated with Com. The partial coefficient between N2O emission rates and corresponding nitrate concentrations in the water was significantly high (r = 0.6834). Compared with Com, CRF was able to reduce N2O emission from the paddy field. Within 100 days after basal application, the N2O emission rate of treatment CRF was only 13.45%-21.26% of Corn and 71.17%-112.47% of CK. The N2O emission of Com was mainly concentrated in 1-25 d after basal fertilization and mid-aeration period, but that of CRF was remarkably lower during same period, while the peak of N2O emission of CK was postponed and reduced. It was concluded that both one-time fertilization of CRF and several-time fertilizations of conventional urea were able to reduce N2O emission from the paddy field.

  15. [Nutrient release characteristics and use efficiency of slow- and controlled release fertilizers].

    Science.gov (United States)

    Duan, Lu-Lu; Zhang, Min; Liu, Gang; Shang, Zhao-Cong; Yang, Yi

    2009-05-01

    Water extraction method and soil incubation method were used to study the nutrient release characteristics of four slow- and controlled release fertilizers (CRF1, CRF2, SCU, and IBDU), and pot experiment was conducted to assess the effects of the release characteristics on the nutrient requirements of canola (Brassica napus L.). The nutrient release curves of test fertilizers in water were S pattern for CRF1 and CRF2, burst pattern for SCU, and reverse L pattern for IBDU. The nutrient release characteristics of the four fertilizers in water and in soil all fitted binomial equations, suggesting that there existed some similarities in the nutrient release in the two media. The nutrient uptake and biomass of canola plants treated with CRF1 and CRF2 were significantly higher than those treated with SCU and IBDU, and CRF2 had the greatest effect. The nutrient release curves of CRF1 and CRF2 accorded more closely with the nutrient requirements of canola.

  16. 包膜控释肥及其包膜材料研究进展%A Review of Controlled Release Fertilizer and Fertilizer Coating Materials

    Institute of Scientific and Technical Information of China (English)

    李慧; 陈少雄

    2012-01-01

    This paper examined differences between the slow release fertilizer and controlled release fertilizer and reviews the course of development of slow/controlled release fertilizers. We classified controlled release fertilizers cun~nfly available on the market in China according to types of coating materials and examine the nutrient release mechanism of the different materials. Methods for detecting the type of coating material were also examined and criteria for evaluating controlled release fertilizers, including some models of their nutrient release, were identified. Shortcomings of the currently available controlled release fertiliTers were discussed and priorities for future development of controlled released fertilizers were discussed.%本文区分了缓释肥、控释肥之间的差别,回顾了国内外缓/控释肥的发展历程,并就目前市场上已有的缓/控释肥,根据其所使用的包膜材料进行了分类,阐述了不同的包膜材料控释肥各自养分释放的机理及包膜材料性质的检测方法,介绍目前已有的缓/控释肥料的评价标准及拟合模型,最后分析了目前的缓/控释肥料的不足,并提出未来控释肥发展的方向。

  17. Heavy Metal Level in Human Semen with Different Fertility: a Meta-Analysis.

    Science.gov (United States)

    Sun, Jiantao; Yu, Guangxia; Zhang, Yucheng; Liu, Xi; Du, Chuang; Wang, Lu; Li, Zhen; Wang, Chunhong

    2017-03-01

    There are conflicting reports on the heavy metal levels in human semen with different fertilities. The purpose of this analysis is to merge and analyze the differences of heavy metal lead (Pb), cadmium (Cd), zinc (Zn), and copper (Cu) levels in male semen with normal and low fertilities. All documents in both Chinese and English were collected from the PubMed, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) database from inception date to February 19, 2016. We have used RevMan software (version 5.2) for the meta-analysis and Stata software (version 12.0) for the meta-regression and sensitivity analyses. A total of 20 literatures were included in the study. The results of the meta-analysis indicate a significant difference between fertility with three metal ions (Pb, Cd, Zn) while no significant difference with copper, detailed as follows: (i) 10 studies on the lead concentrations with a standardized mean difference (SMD) = 2.07, 95 %CI (0.97, 3.17), P < 0.01; (ii) 13 studies on the cadmium concentrations with an SMD = 0.75, 95 %CI (0.44, 1.07), P < 0.01; (iii) 8 studies on the concentrations of zinc with an SMD = -0.61, 95 %CI (-1.08, -0.14), P < 0.01; and (iv) 9 studies on the copper concentrations with an SMD = 0.42, 95 %CI (-0.29, 1.13), P = 0.247. The results indicate that the men with low fertility have higher semen Pb and Cd levels and lower semen Zn levels; more studies are needed to indicate the association of the semen copper level with fertility.

  18. Effects of controlled release fertilizer and foliage fertilizer on potted strawberry%控释肥与叶面肥对盆栽草莓的影响

    Institute of Scientific and Technical Information of China (English)

    蒋成国; 李增红; 周杰; 彭婷亭

    2015-01-01

    以草莓品种‘红颜’为试验材料,通过调查草莓相关指标,探究控释肥与叶面肥对草莓‘红颜’营养生长、繁殖、产量等的影响,为基质盆栽草莓提供施肥技术和方法。结果表明:①叶面肥和控释肥对草莓营养生长有促进作用,除功能叶数外,对其他性状的促进作用都是显著的;控释肥对功能叶数和株高的影响达到极显著水平。②叶面肥增强了草莓的无性繁殖力,有效分株和匍匐茎分别增加了38.64%和133.77%;控释肥增加了草莓的有效分株,而降低了草莓匍匐茎数。③控释肥和叶面肥对基质盆栽草莓结果数和产量都有显著的负面影响。%The strawberry variety ‘Hongyan’was used as a test material,and its vegetative growth,repro-duction and fruit yield were investigated so as to explore controlled release fertilizer and foliage fertilizer practices of soilless potted strawberry.The results indicated that both foliage fertilizer and controlled release fertilizer had a significant accelerating effect on the vegetative growth of strawberry except the functional leaves,while controlled release fertilizer very significantly influenced the number of functional leaves and the plant height;Foliage fertiliz-er enhanced the asexual reproduction of strawberry,with the effective offshoots and stolons increasing by 38.64%and 133.77% respectively;Controlled release fertilizer increased the effective offshoots of strawberry but reduced the number of strawberry runners;Both foliage fertilizer and controlled release fertilizer had a significant negative effect on the fruit number and yield of soilless potted strawberry.

  19. Weed control through seedling abrasion with an organic fertilizer

    Science.gov (United States)

    Many tools exist to control weeds in organic crops, and each has utility in specific situations. Nevertheless, surveys of organic farmers indicate that weed management often is second only to labor supply as their main bottleneck for success. Consequently, new tactics for managing weeds are desirabl...

  20. Cumulative release characteristics of controlled-release nitrogen and potassium fertilizers and their effects on soil fertility, and cotton growth

    OpenAIRE

    Xiuyi Yang; Jibiao Geng; Chengliang Li; Min Zhang; Xiaofei Tian

    2016-01-01

    To investigate the interacting effects of polymer coated urea (PCU) and polymer coated potassium chloride (PCPC) on cotton growth, an experiment was conducted with containerized plants in 2014 and 2015. There were two kinds of nitrogen fertilizer, PCU and urea, which were combined with PCPC at three application rates (40, 80 and 120 kg ha−1). The kinds of nitrogen fertilizer formed the main plot, while individual rates of PCPC were the subplots. The results suggested N and K release patterns ...

  1. Cumulative release characteristics of controlled-release nitrogen and potassium fertilizers and their effects on soil fertility, and cotton growth

    OpenAIRE

    Xiuyi Yang; Jibiao Geng; Chengliang Li; Min Zhang; Xiaofei Tian

    2016-01-01

    To investigate the interacting effects of polymer coated urea (PCU) and polymer coated potassium chloride (PCPC) on cotton growth, an experiment was conducted with containerized plants in 2014 and 2015. There were two kinds of nitrogen fertilizer, PCU and urea, which were combined with PCPC at three application rates (40, 80 and 120 kg ha−1). The kinds of nitrogen fertilizer formed the main plot, while individual rates of PCPC were the subplots. The results suggested N and K release patterns ...

  2. 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.

  3. {sup 15}N uptake from manure and fertilizer sources by three consecutive crops under controlled conditions

    Energy Technology Data Exchange (ETDEWEB)

    Quiroga Garza, Hector Mario, E-mail: quiroga.mario@inifap.gob.m [Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias (INIFAP), Coahuila (Mexico); Delgado, Jorge A.; Wong, Jose Antonio Cueto, E-mail: jorge.delgado@ars.usda.go, E-mail: cueto.jose@inifap.gob.m [United States Dept. of Agriculture (USDA), Fort Collins, CO (United States). Agricultural Research Service. Soil Plant Nutrient Research Unit; Lindemann, William C., E-mail: wlindema@nmsu.ed [New Mexico State University (NMST), Las Cruces, NM (United States). Dept. Agronomy and Horticulture

    2009-09-15

    There are several regions of the world where soil N analysis and/or N budgets are not used to determine how much N to apply, resulting in higher than needed N inputs, especially when manure is used. One such region is the North Central 'La Comarca Lagunera', one of the most important dairy production areas of Mexico. We conducted a unique controlled greenhouse study using {sup 15}N fertilizer and {sup 15}N isotopic-labeled manure that was labeled under local conditions to monitor N cycling and recovery under higher N inputs. The manure-N treatment was applied only once and was incorporated in the soil before planting the first forage crop at an equivalent rate of 30, 60 and 120 Mg ha{sup -1} dry manure. The {sup 15}N treatments were equivalent to 120 and 240 kg ha{sup -1} (NH{sub 4}){sub 2}SO{sub 4}-N for each crop. The total N fertilizer for each N fertilized treatment were 360, and 720 kg ha{sup -1} N. We found very low N recoveries: about 9 % from the manure N inputs, lower than the 22 to 25 % from the fertilizer N inputs. The manure N recovered below ground in soil and roots ranged from 82 to 88 %. The low recoveries of N by the aboveground and low soil inorganic nitrate (NO{sup 3}-N) and ammonium (NH{sub 4}-N) content after the third harvested suggested that most of the {sup 15}N recovered below ground was in the soil organic form. The losses from manure N inputs ranged from 3 to 11 %, lower than the 34 to 39 % lost from fertilizer N sources. Our study shows that excessive applications of manure or fertilizer N that are traditionally used in this region will not increase the rate of N uptake by aboveground compartment but will increase the potential for N losses to the environment. (author)

  4. Land-use versus natural controls on soil fertility in the Subandean Amazon, Peru.

    Science.gov (United States)

    Lindell, Lina; Aström, Mats; Oberg, Tomas

    2010-01-15

    Deforestation to amplify the agricultural frontier is a serious threat to the Amazon forest. Strategies to attain and maintain satisfactory soil fertility, which requires knowledge of spatial and temporal changes caused by land-use, are important for reaching sustainable development. This study highlights these issues by evaluating the relative effects of agricultural land-use and natural factors on chemical fertility of Inceptisols on redbed lithologies in the Subandean Amazon. Macro and micronutrients were determined in topsoil and subsoil in the vicinity of two villages at a total of 80 sites including pastures, coffee plantations, swidden fields, secondary forest and, as a reference, adjacent primary forest. Differences in soil fertility between the land cover classes were investigated by principal component analysis (PCA) and partial least squares regression (PLSR). Primary forest soil was found to be chemically similar to that of coffee plantations, pastures and secondary forests. There were no significant differences between soils of these land cover types in terms of plant nutrients (e.g. N, P, K, Ca, Mg, Mo, Mn, Zn, Cu and Co) or other fertility indicators (OM, pH, BS, EC, CECe and exchangeable acidity). The parent material (as indicated by texture and sample geographical origin) and the slope of the sampled sites were stronger controls on soil fertility than land cover type. Elevated concentrations of a few nutrients (NO(3) and K) were, however detected in soils of swidden fields. Despite being fertile (higher CECe, Ca and P) compared to Oxisols and Ultisols in the Amazon lowland, the Subandean soils frequently showed deficiencies in several nutrients (e.g. P, K, NO(3), Cu and Zn), and high levels of free Al at acidic sites. This paper concludes that deforestation and agricultural land-use has not introduced lasting chemical changes in the studied Subandean soils that are significant in comparison to the natural variability.

  5. APPLICATION OF FOLIAR FERTILIZER AND FUNGICIDES ON WHITE SPOT DISEASE CONTROL AND DEVELOPMENT OF MAIZE

    Directory of Open Access Journals (Sweden)

    C. H. Brito

    2016-11-01

    Full Text Available This study aimed to evaluate the effect of forms of application of foliar fertilizers and fungicides to control fungus causing white maize spot, Phaeosphaeria maydis, and the growth and development of hybrids maize. The design had randomized blocks, with the use two sources hybrids maize with different reaction to white maize spot: resistant and susceptive and application with moisture of foliar chemical fungicide + cobalt foliar + molybdenum foliar + manganese and control treatment, without application consisting of four treatments and five replications. In the treatments with application of moisture were done on vegetative maize growth stage V8 (stage that determine that the number of kernel rows, VT (stage that arrives when the last branch of the tassel is completely visible and reproductive maize growth stage R2 (kernels are white on the outside and resemble a blister. The evaluation of variables of growth of maize plants: grain dry mass, cob dry mass, leaf dry mass, culm dry mass and modificated leaf ear and total plant dry mass. Harvest was carried out when the grains were 20% humidity. The application of fungicides and foliar fertilizers increased the leaves, culm, ear modificated, cobs and shoot dry mass plants maize. The application of fungicides and foliar fertilizers providing returning of 11.409,5 kg ha-1 of shoot dry mass plants with increased of 1.296 kg ha-1 on soil(12,81%. In the susceptive hybrid maize the application of fungicides and foliar fertilizers provide higher dry mass grains and shoot of plants.

  6. 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.

  7. Introduction of human gamma 1 immunoglobulin genes into fertilized mouse eggs.

    Science.gov (United States)

    Yamamura, K; Kikutani, H; Takahashi, N; Taga, T; Akira, S; Kawai, K; Fukuchi, K; Kumahara, Y; Honjo, T; Kishimoto, T

    1984-08-01

    A rearranged human gamma 1 immunoglobulin gene was introduced into fertilized mouse eggs. The phage Ch4A-VCE-gamma 1 was constructed by ligating an EcoRI and BglII fragment of pBR322-CESSV(CE-1) containing the VDJ region with an EcoRI and BamHI fragment of Ch4A-HIg gamma 1-10 containing the gamma 1 constant region. About 200 copies of Ch4A-VCE-gamma 1 genes were introduced into fertilized mouse eggs. Of 489 eggs injected with these genes, 319 survived and were transferred to oviducts of foster mothers. Thirtyeight mice were born and were screened for the presence of human gamma 1 immunoglobulin genes by Southern blot hybridization. Five of these 38 mice had integrated human gamma 1 immunoglobulin genes. None of the human gamma 1 copies in each mouse had undergone deletions or rearrangements as judged by the Southern blotting patterns for several restriction enzymes. Human gamma 1 gene was present in several different tissues. All the mice tested so far transmit the human gamma 1 gene to a fraction of their offspring in an autosomal dominant manner. Spleen cells from transgenic mice were analyzed for immunoglobulin production by reverse plaque assay or immunofluorescence staining of cytoplasmic immunoglobulin, but synthesis and secretion of human gamma 1 chains could not be detected. No human gamma 1 immunoglobulin mRNA was detected in the liver and spleen of a transgenic mouse. The presence of the human gamma 1 immunoglobulin gene appeared to have no effect on the expression of endogenous mouse immunoglobulin genes.

  8. Estimating the impact of birth control on fertility rate in sub-Saharan Africa.

    Science.gov (United States)

    Ijaiya, Gafar T; Raheem, Usman A; Olatinwo, Abdulwaheed O; Ijaiya, Munir-Deen A; Ijaiya, Mukaila A

    2009-12-01

    Using a cross-country data drawn from 40 countries and a multiple regression analysis, this paper examines the impact of birth control devices on the rate of fertility in sub-Saharan Africa. Our a-priori expectations are that the more women used birth control devices, the less will be the fertility rate in sub-Saharan Africa. The result obtained from the study indicates that except for withdrawal method that fall contrary to our expectation other variables (methods) like the use of pills, injection, intra uterine device (IUD), condom/diaphragm and cervical cap, female sterilization and periodic abstinence/rhythm fulfilled our a-priori expectations. These results notwithstanding, the paper suggests measures, such as the need for massive enlightenment campaign on the benefit of these birth control devices, the frequent checking of the potency of the devices and good governance in the delivery of the devices

  9. [Effects of controlled-release N and K fertilizers on N, P, and K use efficiency of mauls (Manlus robusta)].

    Science.gov (United States)

    Shao, Lei; Wang, Li-xia; Zhang, Min; Sun, Zhi-jun

    2010-09-01

    A pot experiment was conducted to study the effects of controlled-release N and K fertilizers on mauls seedlings growth, their P and K use efficiency, and the N balance in soil-plant system. The results showed that the nutrient release from controlled-release fertilizers accorded well with the nutrient requirement of mauls seedlings. Controlled-release N fertilizer significantly increased the K use efficiency, and controlled-release K fertilizer significantly increased the N use efficiency. Under the same K application rate, the plant height and stem diameter under the application of controlled-release N fertilizer (CN) and controlled-release N and K fertilizers (NK) had no significant difference, while those under the application of common fertilizer (SF) were all higher. The plant dry mass and the P and K use efficiency were in the order of NK>CN>SF. Under the application of NK, the application rate of K had no significant effects on the plant height and stem diameter, but significantly affected the plant dry mass. The P use efficiency increased with increasing application rate of controlled-release K fertilizer, but was less affected by application rate common K fertilizer. The K use efficiency decreased with increasing application rate of K. The N use efficiency was in the order of NK>CN>SF, while the N loss rate was in adverse. The residual rate of NK and CN had no significant difference, but was higher than that of SF. The application rate of controlled-release K fertilizer had significant effects on the N use efficiency and N loss rate, but no significant effects on N residual rate.

  10. CREATE TRANSGENIC RABBITS BY MICROINJECTING HUMAN apoA-ⅡGENE INTO FERTILIZED EGGS

    Institute of Scientific and Technical Information of China (English)

    Liu Enqi(刘恩岐); Shuji Kitajima; Masatoshi Morimoto

    2004-01-01

    Objective To create transgenic rabbits by microinjecting human apolipoprotein A-Ⅱ (apoA-Ⅱ) gene into one-cell embryos, to study apoA-Ⅱ gene function on plasma lipoprotein metabolism and atherosclerosis. Methods Superovulation and synchronization of estrus were induced in female Japanese White Rabbits by injecting hormone, then mating with male. After collected the fertilized eggs, the human apoA-Ⅱ gene was microinjected into the male pronucleus of eggs. The injected eggs were transferred into recipient female rabbits. Last, extract DNA from the new borns ear and determine whether the newborns were transgenic by polymerase chain reaction (PCR) or Southern blot analysis. Results A total of 822 embryos with microinjection of human apoAⅡ gene were implanted into 28 recipient rabbits. The number of surviving newborns was 37. 3 transgenic positive surviving founders were found with human apoA-Ⅱ.

  11. Ultrasound characteristics and histological dating of the endometrium in a natural cycle in infertile women compared with fertile controls

    DEFF Research Database (Denmark)

    Lindhard, A; Ravn, V; Bentin-Ley, U

    2006-01-01

    OBJECTIVE: To compare endometrial dating and ultrasound texture in a natural cycle before IVF and relate these to outcome and to fertile references. DESIGN: Prospective study with a fertile reference group. SETTING: Four university IVF clinics. PATIENT(S): Seventy-five IVF patients and 21 fertile...... in nonpregnant women compared with in women with ongoing pregnancies and with fertile controls. A periovulatory hyperechogenic endometrium resulted in no ongoing pregnancies. CONCLUSION(S): In a natural cycle preceding IVF, a low midluteal P level predicts a low implantation rate. A periovulatory hyperechogenic...... women. INTERVENTION(S): Ultrasound, biopsy, blood sampling. In vitro fertilization-ET in the following cycle. MAIN OUTCOME MEASURE(S): Endometrial evaluation, P, IVF outcome. RESULT(S): At day LH+7, 42% infertile vs. 67% fertile women demonstrated endometria that were in phase (statistically...

  12. [Effects of controlled-release fertilizer on chrysanthemum leaf chlorophyll fluorescence characteristics and ornamental quality].

    Science.gov (United States)

    Song, Xu-xu; Zheng, Cheng-shu; Sun, Xia; Ma, Hai-yan

    2011-07-01

    Taking cut flower chrysanthemum 'Baima' as test material, a pot experiment was conducted to study the effects of controlled-release fertilizer on the leaf chlorophyll fluorescence parameters, chlorophyll and nutrient contents, and ornamental quality of chrysanthemum. Under no fertilization, the maximal photochemical efficiency of PS II in dark (F(v)/F(m)), potential photochemical efficiency of PS II (F(v)/F(0)), and quantum yield of PS II electron transport (phi(PS II)) decreased significantly, compared with those under fertilization. With the application of conventional compound fertilizers CCFA (N:P:K=20:8:10) and CCFB (N:P:K= 14:14:14), the F(v)/F(m), F(v)/F(0) and phi(PS II) had a slight increase in early period (30-60 d) but a remarkable decrease in mid and later periods (75 - 120 d), compared with those under the application of controlled-release fertilizers CRFA (N:P:K = 20:8:10) and CRFB (N:P:K= 14:14:14). Under the application of CRFA, the F(v)/F(m), phi(PS II), and photochemical quenching (q(P)) had somewhat increase, as compared with the application of CRFB. The non-photochemical quenching (NPQ) under the application of CRFA and CRFB decreased significantly, compared with that under the application of CCFA and CCFB and the control. The chlorophyll content had a similar change trend with F(v)/F(m), F(v)/F(0), and phi(PS II). The leaf N, P, and K contents, flower stalk length and stalk diameter, flower diameter, and flower fresh and dry mass at harvest stage all increased under the application of CRFA and CRFB, compared with those under the application of CCFA and CCFB and the control, and the flower fresh and dry mass was significantly higher under the application of CRFA than of CRFB. This study showed that controlled-release fertilizer could improve the ornamental quality of chrysanthemum via improving the leaf chlorophyll content, photochemical transduction rate, and nutrient uptake, and CRFA had better effects than CRFB.

  13. Using iron fertilizer to control Cd accumulation in rice plants: A new promising technology

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Effects of two kinds of iron fertilizer, FeSO4 and EDTA·Na2Fe were studied on cadmium accumulation in rice plants with two rice genotypes, Zhongzao 22 and Zhongjiazao 02, with soil culture systems. The results showed that application of iron fertilizers could hardly make adverse effects on plant growth and rice grain yield. Soil application of EDTA·Na2Fe significantly reduced the Cd accumulation in rice roots, shoots and rice grain. Cd concentration in white rice of both rice genotypes in the treatment of soil application of EDTA·Na2Fe was much lower than 0.2 mg/kg, the maximal Cd permission concentra- tion in cereal crop foods in State standard. However, soil application of FeSO4 or foliar application of FeSO4 or EDTA·Na2Fe resulted in the significant increase of Cd accumulation in rice plants including rice grain compared with the control. The results also showed iron fertilizers increased the concentra- tion of iron, copper and manganese element in rice grain and also affected zinc concentration in plants. It may be a new promising way to regulate Cd accumulation in rice grain in rice production through soil application of EDTA·Na2Fe fertilizers to maintain higher content of available iron and ferrous iron in soils.

  14. Using iron fertilizer to control Cd accumulation in rice plants: a new promising technology.

    Science.gov (United States)

    Shao, GuoSheng; Chen, MingXue; Wang, DanYing; Xu, ChunMei; Mou, RenXiang; Cao, ZhaoYun; Zhang, XiuFu

    2008-03-01

    Effects of two kinds of iron fertilizer, FeSO4 and EDTA.Na2Fe were studied on cadmium accumulation in rice plants with two rice genotypes, Zhongzao 22 and Zhongjiazao 02, with soil culture systems. The results showed that application of iron fertilizers could hardly make adverse effects on plant growth and rice grain yield. Soil application of EDTA.Na2Fe significantly reduced the Cd accumulation in rice roots, shoots and rice grain. Cd concentration in white rice of both rice genotypes in the treatment of soil application of EDTA.Na2Fe was much lower than 0.2 mg/kg, the maximal Cd permission concentration in cereal crop foods in State standard. However, soil application of FeSO4 or foliar application of FeSO4 or EDTA.Na2Fe resulted in the significant increase of Cd accumulation in rice plants including rice grain compared with the control. The results also showed iron fertilizers increased the concentration of iron, copper and manganese element in rice grain and also affected zinc concentration in plants. It may be a new promising way to regulate Cd accumulation in rice grain in rice production through soil application of EDTA.Na2Fe fertilizers to maintain higher content of available iron and ferrous iron in soils.

  15. Using iron fertilizer to control Cd accumulation in rice plants: A new promising technology

    Institute of Scientific and Technical Information of China (English)

    SHAO GuoSheng; CHEN MingXue; WANG DanYing; XU ChunMei; MOU RenXiang; CAO ZhaoYun; ZHANG XiuFu

    2008-01-01

    Effects of two kinds of iron fertilizer, FeSO4 and EDTA·Na2Fe were studied on cadmium accumulation in rice plants with two rice genotypes, Zhongzao 22 and Zhongjiazao 02, with soil culture systems. The results showed that application of iron fertilizers could hardly make adverse effects on plant growth and rice grain yield. Soil application of EDTA.Na=Fe significantly reduced the Cd accumulation in rice roots, shoots and rice grain. Cd concentration in white rice of both rice genotypes in the treatment of soil application of EDTA·Na2Fe was much lower than 0.2 mg/kg, the maximal Cd permission concentration in cereal crop foods in State standard. However, soil application of FeSO4 or foliar application of FeSO4 or EDTA·Na2Fe resulted in the significant increase of Cd accumulation in rice plants including rice grain compared with the control. The results also showed iron fertilizers increased the concentration of iron, copper and manganese element in rice grain and also affected zinc concentration in plants.It may be a new promising way to regulate Cd accumulation in rice grain in rice production through soil application of EDTA·Na2Fe fertilizers to maintain higher content of available iron and ferrous iron in soils.

  16. Controlling fertilization and cAMP signaling in sperm by optogenetics.

    Science.gov (United States)

    Jansen, Vera; Alvarez, Luis; Balbach, Melanie; Strünker, Timo; Hegemann, Peter; Kaupp, U Benjamin; Wachten, Dagmar

    2015-01-20

    Optogenetics is a powerful technique to control cellular activity by light. The light-gated Channelrhodopsin has been widely used to study and manipulate neuronal activity in vivo, whereas optogenetic control of second messengers in vivo has not been examined in depth. In this study, we present a transgenic mouse model expressing a photoactivated adenylyl cyclase (bPAC) in sperm. In transgenic sperm, bPAC mimics the action of the endogenous soluble adenylyl cyclase (SACY) that is required for motility and fertilization: light-stimulation rapidly elevates cAMP, accelerates the flagellar beat, and, thereby, changes swimming behavior of sperm. Furthermore, bPAC replaces endogenous adenylyl cyclase activity. In mutant sperm lacking the bicarbonate-stimulated SACY activity, bPAC restored motility after light-stimulation and, thereby, enabled sperm to fertilize oocytes in vitro. We show that optogenetic control of cAMP in vivo allows to non-invasively study cAMP signaling, to control behaviors of single cells, and to restore a fundamental biological process such as fertilization.

  17. 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.

  18. Exploiting common targets in human fertilization and HIV infection: development of novel contraceptive microbicides.

    Science.gov (United States)

    Doncel, Gustavo F

    2006-01-01

    The continued high rates of unintended pregnancies and the unrelentless expansion of the acquired immune deficiency syndrome (AIDS) epidemic, especially in less developed countries, warrant the development of novel strategies to help individuals avoid these risks. Dually active compounds displaying contraceptive and microbicidal anti-human immunodeficiency virus (anti-HIV) properties constitute one such strategy. Sharing the same anatomical and functional context, sperm fertilization and genital infection by HIV offer an opportunity for simultaneous intervention. Some of the molecules and mechanisms used by sperm to fertilize the oocyte are similar, if not identical, to those used by HIV while infecting host cells. An example of common structures is the lipid membrane surrounding the spermatozoon and the HIV core. Disruption of its architecture by surface-active compounds exerts both spermicidal and virucidal activity. A more specific alteration of lipid rafts [membrane microdomains enriched in cholesterol and glycosylphosphatidylinositol (GPI)-anchored proteins] by beta-cyclodextrins also results in similar effects. During fertilization and infection, both sperm and HIV interact with their target cell receptors through chemical charges, hydrophobic forces and carbohydrate recognition. Anionic polymers such as cellulose sulphate and polystyrene sulphonate (PSS) inhibit sperm and HIV cell binding. Because some of the molecules involved in this interaction, e.g. heparin sulphate proteoglycan, are also used by other pathogens to infect their target tissues, polyanions exert broad antimicrobial activity as well. During fertilization and infection, sperm and HIV, as well as other microbes, use signal transduction molecules and mechanisms such as adenyl cyclase/cyclic adenosine monophosphate (cAMP)-dependent kinase, calcium and tyrosine phosphorylation, whose inhibition has been shown to impair sperm function and HIV replication. These commonalities at the level of sperm

  19. Intercalation of urea into kaolinite for preparation of controlled release fertilizer

    OpenAIRE

    Mahdavi Fariba; Abdul Rashid Suraya; Khanif Yusop Mohd

    2014-01-01

    In this study urea was intercalated between layers of kaolinite by dry grinding technique to be used for preparing controlled release fertilizer. X-ray powder diffraction (XRPD) patterns confirmed the intercalation of urea into kaolinite by the significant expansion of the basal spacing of kaolinite layers from 0.710 nm to 1.090 nm. Fourier transform infrared spectroscopy (FT-IR) also confirmed the hydrogen bonding between urea and kaolinite. Based on CHNS ...

  20. Fertility Effects of Abortion and Birth Control Pill Access for Minors

    OpenAIRE

    GULDI, MELANIE

    2008-01-01

    This article empirically assesses whether age-restricted access to abortion and the birth control pill influence minors’ fertility in the United States. There is not a strong consensus in previous literature regarding the relationship between laws restricting minors’ access to abortion and minors’ birthrates. This is the first study to recognize that state laws in place prior to the 1973 Roe v. Wade decision enabled minors to legally consent to surgical treatment—including abortion—in some st...

  1. Intercalation of urea into kaolinite for preparation of controlled release fertilizer

    OpenAIRE

    Mahdavi Fariba; Abdul Rashid Suraya; Khanif Yusop Mohd

    2014-01-01

    In this study urea was intercalated between layers of kaolinite by dry grinding technique to be used for preparing controlled release fertilizer. X-ray powder diffraction (XRPD) patterns confirmed the intercalation of urea into kaolinite by the significant expansion of the basal spacing of kaolinite layers from 0.710 nm to 1.090 nm. Fourier transform infrared spectroscopy (FT-IR) also confirmed the hydrogen bonding between urea and kaolinite. Based on CHNS ...

  2. The Effects of Controlled Release Fertilizer and Conventional Complex Fertilizer on the Dry Matter Accumulation and the Yield in Winter Wheat

    Directory of Open Access Journals (Sweden)

    Guoqing Li

    2013-03-01

    Full Text Available In order to research the use ratio of controlled release fertilizer in winter wheat. So, the experiment about the effects of Controlled Release Fertilizer (CRF and Conventional Complex Fertilizer (CCF on the dry matter accumulation and the grain yield in winter wheat has studied with pots in the open field. The results indicated that the CRF improved the proportion of the number of effective tillers to the total number of tillers. And the mixture of the CRF and equivalent CCF have more improved the proportion of the dry root weight to the total dry matters of the after of wheat flowering stage than that of the CRF used alone (T1, T2, T3. The treatment T6 was more improved the accumulation of the dry matters of aerial part than others. And the weight gain of T6 after a thesis was higher than other treatments and the control treatment (CK. In the facts of grain number per spike, thousand grain weight and yield, the treatments of the mixture of the CRF and equivalent CCF (T4,T5,T6 were higher than that of the treatments of CRF used only (T1,T2,T3 and CK, in which the T6 was highest. So, we think that this treatment namely T6 was used fertilizers least and gained the highest yield of grain.

  3. Nutrients Release from a Novel Gel-Based Slow/Controlled Release Fertilizer

    Directory of Open Access Journals (Sweden)

    H. Ding

    2016-01-01

    Full Text Available A novel gel-based slow/controlled release fertilizer (G-CRF was developed, which was produced by combining various natural, seminatural, and/or synthetic organic macromolecule materials and natural inorganic mineral with conventional NPK fertilizers. Its nutrient release characteristics were studied to compare with conventional fertilizers through the soil column leaching method. The influences of soil factors, including temperature, pH, water, and nutrient contents in the G-CRF on nutrient release, were also investigated through soil-water incubation method. These results indicated that the G-CRF had better effect on controlling release of N, P, and K nutrients, and the effect was more efficient when soil-water content was lower than 45% (w/w, temperature was below 35°C, and soil pH was in the range from weak acid to neutral. In addition, considering the effect of controlling nutrient release and cost of the materials in the G-CRF, it is recommended that the most feasible NPK nutrient contents in the G-CRF ranged from 30 to 35%.

  4. Intercalation of urea into kaolinite for preparation of controlled release fertilizer

    Directory of Open Access Journals (Sweden)

    Mahdavi Fariba

    2014-01-01

    Full Text Available In this study urea was intercalated between layers of kaolinite by dry grinding technique to be used for preparing controlled release fertilizer. X-ray powder diffraction (XRPD patterns confirmed the intercalation of urea into kaolinite by the significant expansion of the basal spacing of kaolinite layers from 0.710 nm to 1.090 nm. Fourier transform infrared spectroscopy (FT-IR also confirmed the hydrogen bonding between urea and kaolinite. Based on CHNS elemental analysis, 20% (wt. urea was intercalated between kaolinite layers. The urea-intercalated kaolinite was mixed with hydroxypropyl methylcellulose (HPMC binder and was granulated to prepare the nitrogen-based controlled release fertilizer. To study the nitrogen release behavior of granules, ultraviolet/visible (UV-Vis spectroscopy was used through the diacetyl monoxime (DAM colorimetric method. The result of UV-Vis spectroscopy showed that intercalation of urea into kaolinite decreased the nitrogen release from 25.50 to 13.66 % after 24 hours and from 98.15 to 70.01% after 30 days incubation in water. According to the results, the prepared controlled release fertilizer (CRF behaved according to the standard for CRFs.

  5. Human Herpes Virus Type 2 (HSV2), Human Cytomegalovirus (HCMV) in the Male Genital Tract and Fertilization

    Institute of Scientific and Technical Information of China (English)

    Courtot Anne Marie; Pallier Coralie; Testart Jacques

    2003-01-01

    The possibility of infection of the human male genital tract by human herpes virus type 2 (HSV2) or human cytomegalovirus (HCMV) is well established and their sexual transmission has been the object of many studies. Moreover, medically assisted procreation, which helps in numerous fertility problems, raises the question of new viral risks linked to the application of these new technologies. In this review, we shall consider current knowledge in terms of the presence of HSV2 and HCMV in the different parts of the genital tract of immunocompetent or immunodepressed men. We shall also consider the possibility of viral transmission by the sexual act or by the various techniques used in medically assisted procreation. We shall describe studies in human beings and in animals.

  6. [Effects of controlled-release fertilizers on summer maize grain yield, field ammonia volatilization, and fertilizer nitrogen use efficiency].

    Science.gov (United States)

    Zhao, Bin; Dong, Shu-Ting; Wang, Kong-Jun; Zhang, Ji-Wang; Liu, Peng

    2009-11-01

    A field experiment with colophony-coated fertilizer (CRF) and sulfur-coated fertilizer (SCF) showed that under the same application rates of N, P and K, applying CRF and SCF increased the summer maize grain yield by 13.15% and 14.15%, respectively, compared to the application of common compound fertilizer CCF. When the applied amount of CRF and SCF was decreased by 25%, the yield increment was 9.69% and 10.04%, respectively; and when the applied amount of CRF and SCF was decreased by 50%, the yield had less difference with that under CCF application. The field ammonia volatilization rate in treatments CRF and SCF increased slowly, with a peak appeared 7 days later than that in treatment CCF, and the total amount of ammonia volatilization in treatments CRF and SCF was ranged from 0.78 kg N x hm(-2) to 4.43 kg N x hm(-2), with a decrement of 51.34%-91.34% compared to that in treatment CCF. The fertilizer nitrogen use efficiency and agronomic nitrogen use efficiency of CRF and SCF were also significantly higher than those of CCF.

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

    Science.gov (United States)

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

    2015-01-01

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

  8. [Soil biological activities at maize seedling stage under application of slow/controlled release nitrogen fertilizers].

    Science.gov (United States)

    Li, Dongpo; Wu, Zhijie; Chen, Lijun; Liang, Chenghua; Zhang, Lili; Wang, Weicheng; Yang, Defu

    2006-06-01

    With pot experiment and simulating field ecological environment, this paper studied the effects of different slow/ controlled release N fertilizers on the soil nitrate - reductase and urease activities and microbial biomass C and N at maize seedling stage. The results showed that granular urea amended with dicyandiamide (DCD) and N-(n-bultyl) thiophosphoric triamide (NBPT) induced the highest soil nitrate-reductase activity, granular urea brought about the highest soil urease activity and microbial biomass C and N, while starch acetate (SA)-coated granular urea, SA-coated granular urea amended with DCD, methyl methacrylate (MMA) -coated granular urea amended with DCD, and no N fertilization gave a higher soil urease activity. Soil microbial C and N had a similar variation trend after applying various kinds of test slow/controlled release N fertilizers, and were the lowest after applying SA-coated granular urea amended with DCD and NBPT. Coated granular urea amended with inhibitors had a stronger effect on soil biological activities than coated granular urea, and MMA-coating had a better effect than SA-coating.

  9. Preparation and Testing of Cementing and Coating Nano-Subnanocomposites of Slow/Controlled-Release Fertilizer

    Institute of Scientific and Technical Information of China (English)

    LIU Xiu-mei; FENG Zhao-bin; ZHANG Fu-dao; ZHANG Shu-qing; HE Xu-sheng

    2006-01-01

    To select the cementing and coating materials of slow/controlled-release fertilizer, the natural kaoline and abandoned foam plastics were used to prepare nano-subnanocomposites through the methods of organic material intercalation, semiemulsification, and cut at high velocity techniques. Besides, two kinds of nano-subnanocomposites were tested in this study using several instruments, including the scanning electron microscope (SEM), the X-ray diffraction (XRD), the infrared ray spectrum (IR), and the laser granularity. The main results were as follows: 1) The organic material was intercalated in the layers of kaoline clays, and the natural kaoline exfoliated into nanometer-sized layers. The organic agent and clays formed nanocomposites through hydrogen bond combination. 2) The SEM pictures of polystyrenestarch nano-subnanocomposites showed that many pores and rugas were present on the surface of film at sizes ranging from 10 to 20 nm. These nano-subnanocomposites were used as the cementing and coating materials of slow/controlledrelease fertilizer.

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

    OpenAIRE

    Nelson, Kelly A.; Peter P. Motavalli; Stevens, William E.; Kendig, John A.; David Dunn; Manjula Nathan

    2012-01-01

    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 ...

  11. Persistent organic pollutants (POPs) in human follicular fluid and in vitro fertilization outcomes, a pilot study.

    Science.gov (United States)

    Bloom, Michael S; Fujimoto, Victor Y; Storm, Robin; Zhang, Li; Butts, Celeste D; Sollohub, Diana; Jansing, Robert L

    2017-01-01

    Persistent organic pollutants (POPs) are ubiquitously distributed among the U.S. population and adversely impact human reproduction. These compounds have been detected in human ovarian follicular fluid (FF), where they directly contact a developing oocyte. As a pilot investigation, we measured 43 polychlorinated biphenyl (PCB) congeners, p,p'-dichlorodiphenyltrichloroethane (DDT), and its persistent metabolite p,p'-dichlorodiphenyldichloroethylene (DDE) in residual FF collected from 32 women undergoing in vitro fertilization (IVF). We identified significant inverse associations between higher levels of PCB congeners and indicators of ovarian reserve (e.g., antral follicle count), follicular response to administered gonadotropins (e.g., peak estradiol, number of oocytes retrieved, endometrial thickness), intermediate IVF endpoints (e.g., oocyte fertilization and embryo quality), and clinical IVF outcomes (e.g., embryo implantation and live birth), after adjusting for body mass index, cigarette smoking, race, and age. Our results suggest that ongoing exposure to POPs impacts IVF and merit confirmation in a larger and more definitive future study. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Characterization of fertilization-blocking monoclonal antibody 1G12 with human sperm-immobilizing activity

    Science.gov (United States)

    KOMORI, S; KAMEDA, K; SAKATA, K; HASEGAWA, A; TOJI, H; TSUJI, Y; SHIBAHARA, H; KOYAMA, K; ISOJIMA, S

    1997-01-01

    A mouse hybridoma (1G12) producing sperm-immobilizing MoAb to human sperm was established and characterized in order to study the antigens relevant to sperm immobilization by antibodies. MoAb 1G12 had strong sperm-immobilizing and agglutinating activities and also showed a fertilization-blocking activity on in vitro fertilization tests. The antibody absorption experiments showed that MoAb 1G12 reacted not only to ejaculated sperm but also human seminal plasma, suggesting that the corresponding antigen might be a sperm coating antigen. The MoAb also reacted with peripheral blood lymphocytes. In histochemical studies, the epithelia of corpus epididymis were most strongly stained. Ejaculated sperm were stained with a granular pattern for their entire surface by immunofluorescence. MoAb 1G12 recognized polymorphic glycoproteins of 15–25 kD in the ejaculated sperm extract in Western blot analysis. After deglycosilation of the sperm extract, only a single staining band of under 15 kD was detected by MoAb 1G12. This suggests that the antigen epitope recognized by MoAb 1G12 might be a peptide of the core portion of the glycoprotein. MoAb 1G12 might be a useful tool for studying the mechanism of egg–sperm interaction, and also be applied to identifying the corresponding antigen by using gene technology. PMID:9328135

  13. Dog population management for the control of human echinococcosis.

    Science.gov (United States)

    Kachani, Malika; Heath, David

    2014-11-01

    Cystic and alveolar hydatid disease of humans caused by infection with Echinococcus granulosus or Echinococcus multilocularis are significant zoonoses in developing countries. For human infections, the main definitive host is the dog, and reduction in the population of unwanted dogs, together with anthelmintic treatment of wanted dogs, are recommended control procedures for these zoonoses. Both owned and unowned dogs have been shown to be a major source of Echinococcus spp. infection in developing countries. Unowned dogs are the most challenging category in dog population management for the control of major zoonotic diseases. Unowned dogs are those dogs that do not have an owner, and those dogs whose owner cannot readily be identified. Control of numbers of unowned dogs can be done in various ways if funds are available. Fertility control and humane euthanasia are likely to be the most effective procedures in developing countries. Fertility control requires significant funding, and where resources are scarce humane euthanasia may be the most effective option. Both procedures are ongoing events, with no predictable end point. This paper examines the sociology and technology for the population management of owned and unowned dogs, specifically for the reduction of human hydatid disease. Examples are given for developing and developed countries. Although a "One Health" approach is desirable, the technology for hydatid control is different from that for rabies, and FAO Animal Welfare recommendations for dog population management should be adjusted accordingly.

  14. Effects of solid water and foliar fertilizer on survival and growth of seedlings in sand prevention and control

    Institute of Scientific and Technical Information of China (English)

    WANG Yutao; LI Jiyue; LIU Ping

    2007-01-01

    To promote afforestation in sandy lands and increase the effects of prevention and control of desertification,the application of a new drought-resistant productsolid water and foliar fertilizer "Shifengle"-was studied.A comparison of three treatments (solid water,foliar fertilizer,and control) showed that both solid water and foliar fertilizer increased plant survival rate by 10% and 18.2%,respectively.Afforestation survival rates of Salix psammophila and Hedysarum mongolicum reached over 90%.In addition,height and crown growth as well as biomass of seedlings were improved by the treatments.

  15. Enrichment of fertilizers with zinc: An excellent investment for humanity and crop production in India.

    Science.gov (United States)

    Cakmak, Ismail

    2009-01-01

    Micronutrient malnutrition is a growing concern in the developing world, resulting in diverse health and social problems, such as mental retardations, impairments of the immune system and overall poor health. In recent years, the zinc (Zn) deficiency problem has received increasing attention and appears to be the most serious micronutrient deficiency together with vitamin A deficiency. Zinc deficiency is particularly widespread among children and represents a major cause of child death in the world. In countries where Zn deficiency is well documented as an important public health problem, cereal-based foods are the predominant source of daily calorie and protein intake. Because the concentration of Zn in cereal crops is inherently very low, growing cereals on potentially Zn-deficient soils further decreases grain Zn concentrations. It is, therefore, not surprising that high Zn deficiency incidence in humans occurs predominantly on areas where soils are deficient in plant-available Zn, as shown in many Southeast Asian countries. India has some of the most Zn-deficient soils in the world. Nearly 50% of cultivated soils in India are low in plant-available Zn; these soils are under intensive cultivation of wheat and rice with no or little application of Zn fertilizers. Consequently, cereal crops grown on such Zn-deficient soils contribute only marginally to daily Zn intake. In the rural areas of India, rice and wheat contributes nearly 75% of the daily calorie intake. These facts clearly point to an urgent need for improved Zn concentration of cereal grains in India. Recent calculations indicate that biofortification (enrichment) of rice and wheat grain with Zn, for example by breeding, may save lives of up to 48,000 children in India annually. Breeding new cereal genotypes for high grain Zn concentration is the most realistic and cost-effective strategy to address the problem. However, this strategy is a long-term one, and the size of plant-available Zn pools in soils

  16. Evaluation of Methods for Control of Ammonia Volatilization from Surface—Applied Nitrogen Fertilizers to Sugarcane Trash in North Queensland

    Institute of Scientific and Technical Information of China (English)

    KONGWEI-PING; A.W.WOOD; 等

    1993-01-01

    Micrometeorological and microplot experiments were conducted in the field of freshly harvested green cane in Queensland,Australia.Results showed that high ammonia loss of fertilizer N could occur under relatively dry conditions when urea or commercial product of mixture of urea and muriate of potash were applied to the surface of sugarcane trash.The moisture content in the trash and the pH of fertilizer were two important factors controlling the processes of urea hydrolysis and ammonia volatilization.Most of the N in the soil was transformed to the nitratel-nitrite from after 70 days of fertilizer application.No significant leaching was found.Urea-free N fertilizers had higher N recoveries compared to urea-containing fertilizers.

  17. 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

  18. Disease control through fertility control: Secondary benefits of animal birth control in Indian street dogs.

    Science.gov (United States)

    Yoak, Andrew J; Reece, John F; Gehrt, Stanley D; Hamilton, Ian M

    2014-01-01

    We sought to (1) survey sexually intact street dogs for a wide range of diseases in three cities in Rajasthan, India and (2) evaluate links between the health of non-treated dogs and both the presence and duration of animal birth control (ABC) programs. ABC regimes sterilize and vaccinate stray dogs in an attempt to control their population and the spread of rabies. They are commonly suggested to improve the health of those dogs they serve, but here we provide evidence that these benefits also extend to untreated dogs in the community. Viral and bacterial disease seroprevalences were assessed in 240 sexually intact street dogs from Jaipur, Jodhpur, and Sawai Madhopur cities in October and September 2011. Those individuals and 50 additional dogs were assessed for the presence of ticks, fleas, fight wounds, and given body condition scores. Dogs in cities with an ABC program had with significantly (phepatitis, Ehrlichia canis, Leptospira interrogans serovars, and canine distemper virus antibodies. However, those same dogs in cities with ABC programs had significantly higher prevalence of Brown Dog Tick (Rhipicephalus sanguineus) infestations. Canine parvovirus and Brucella canis prevalences were not significantly different between cities. This study is the first to demonstrate the health benefits of ABC on non-vaccinated diseases and non-treated individuals. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  19. Modeling controlled nutrient release from polymer coated fertilizers: diffusion release from single granules.

    Science.gov (United States)

    Shaviv, Avi; Raban, Smadar; Zaidel, Elina

    2003-05-15

    A comprehensive model describing the complex and "non-Fickian" (mathematically nonlinear) nature of the release from single granules of membrane coated, controlled release fertilizers (CRFs) is proposed consisting of three stages: i. a lag period during which water penetrates the coating of the granule dissolving part of the solid fertilizer in it ii. a period of linear release during which water penetration into and release out occur concomitantly while the total volume of the granules remains practically constant; and iii. a period of "decaying release", starting as the concentration inside the granule starts to decrease. A mathematical model was developed based on vapor and nutrient diffusion equations. The model predicts the release stages in terms of measurable geometrical and chemophysical parameters such as the following: the product of granule radius and coating thickness, water and solute permeability, saturation concentration of the fertilizer, and its density. The model successfully predicts the complex and "sigmoidal" pattern of release that is essential for matching plant temporal demand to ensure high agronomic and environmental effectiveness. It also lends itself to more complex statistical formulations which account for the large variability within large populations of coated CRFs and can serve for further improving CRF production and performance.

  20. Perfluoroalkyl and polyfluoroalkyl substances and measures of human fertility: a systematic review.

    Science.gov (United States)

    Bach, Cathrine Carlsen; Vested, Anne; Jørgensen, Kristian Tore; Bonde, Jens Peter Ellekilde; Henriksen, Tine Brink; Toft, Gunnar

    2016-10-01

    Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are found widespread in the environment and humans. The relation of PFASs to fertility has now been examined in a relatively large number of epidemiologic studies and a synthesis is in order. The aim of this study was to assess the current human epidemiologic evidence on the association between exposure to PFASs and measures of human fertility, with particular emphasis on perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA). Systematic literature searches were initially conducted in MEDLINE and EMBASE and subsequently in references and citations of included papers. Studies were included if they assessed exposure to PFASs in biological samples in relation to reproductive hormones, semen characteristics, or time to pregnancy (TTP). Study characteristics and results were abstracted to predefined forms, and the studies were assessed for the risk of bias and confounding. Sixteen studies investigated the association between PFAS exposure in men and semen parameters, reproductive hormone levels, or TTP. There was a lack of consistent results among the numerous investigated exposure-outcome combinations. However, subtle associations between higher PFOS and lower testosterone or abnormal semen morphology cannot be excluded. Eleven studies assessed the association between PFAS exposure in women and TTP or reproductive hormones levels. Four of eight studies found prolonged TTP with higher PFOS or PFOA, but only one study found an association when restricting to nulliparous women. In men, there is little evidence of an association between PFAS exposure and semen quality or levels of reproductive hormones. For PFOS and PFOA, the literature indicates an association with female fecundability in parous women, which is most likely not causal.

  1. Toxic trace metals and human oocytes during in vitro fertilization (IVF)

    Science.gov (United States)

    Bloom, Michael S.; Parsons, Patrick J.; Steuerwald, Amy J.; Schisterman, Enrique F.; Browne, Richard W.; Kim, Keewan; Coccaro, Gregory A.; Conti, Giulia C.; Narayan, Natasha; Fujimoto, Victor Y.

    2010-01-01

    Trace exposures to the toxic metals mercury (Hg), cadmium (Cd) and lead (Pb) may threaten human reproductive health. The aim of this study is to generate biologically-plausible hypotheses concerning associations between Hg, Cd, and Pb and in vitro fertilization (IVF) endpoints. For 15 female IVF patients, a multivariable log-binomial model suggests a 75% reduction in the probability for a retrieved oocyte to be in metaphase-II arrest for each μg/dL increase in blood Pb concentration (relative risk (RR) = 0.25, 95% confidence interval (CI) 0.03–2.50, P = 0.240). For 15 male IVF partners, each μg/L increase in urine Cd concentration is associated with an 81% decrease in the probability for oocyte fertilization (RR = 0.19, 95% CI 0.03–1.35, P = 0.097). Because of the magnitude of the effects, these results warrant a comprehensive study with sufficient statistical power to further evaluate these hypotheses. PMID:20096775

  2. 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 < 0.05). The catalytic activity of UCHL3 was decreased in spermatozoa from A or OA (p < 0.05, p < 0.001, respectively). The level and activity of UCHL3 were positively correlated with 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. PMID:27780264

  3. 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

  4. Evaluation of Animal Dungs and Organomineral Fertilizer for the Control of Meloidogyne incognita on Sweet Potato

    Directory of Open Access Journals (Sweden)

    Oluremi Solomon Osunlola

    2015-01-01

    Full Text Available Root-knot nematode, Meloidogyne incognita, is an important animate pathogen causing major damage and severe reductions in the growth, yield, and quality of sweet potato. Nematicides are expensive and their application also causes environmental pollution. A field experiment was therefore conducted to evaluate the effectiveness of poultry dung (10 or 20 t/ha, cow dung (10 or 20 t/ha, horse dung (10 or 20 t/ha, goat dung (10 or 20 t/ha, organomineral fertilizer (2 or 4 t/ha, and carbofuran (3 kg a.i/ha in the management of M. incognita on sweet potato using a randomized complete block design. The unamended plots served as control. Data were analysed using ANOVA (p≤0.05. All organic materials and carbofuran significantly (p≤0.05 reduced nematode reproduction and root damage compared with control. Poultry dung (10 and 20 t/ha and carbofuran were, however, more efficient in nematode control than other organic materials. Sweet potato plants that were grown on soil treated with organomineral fertilizer had the highest mean number of vines and fresh shoot weight, while poultry dung improved sweet potato quality and yield. It is therefore recommended that the use of poultry dung be employed in combination with other nematode control strategies to achieve sustainable, economic, and environment-friendly nematode management.

  5. Response of faba bean to phosphate fertilizer and weed control on nitisols of ethiopian highlands

    Directory of Open Access Journals (Sweden)

    Getachew Agegnehu

    Full Text Available The effects of phosphorus fertilizer and weed control on yield and major yield components of faba bean (Vicia faba L. were studied on Nitisols of Ethiopian highlands. Factorial combinations of four levels of phosphorus fertilizer (0, 10, 20 and 30 kg P ha-1 as triple super phosphate (TSP and two levels of weeding (W1 = no weeding and W2 = hand weeding once six weeks after crop emergence were laid out in randomized complete block design with three replications. Results indicated that highly significant positive responses of number of pods per plant, total biomass and seed yields of faba bean to phosphorus fertilizer and weeding treatments were noted. Phosphorus level × weed control interaction over three years significantly (P ≤ 0.05 affected faba bean seed yield at Rob Gebeya but not at Welmera. Phosphorus application at the rates of 10, 20 and 30 kg P ha-1 resulted in mean seed yield increases compared to the control of 20, 41 and 53%, respectively on the average of locations; 13, 33 and 51%, respectively at Welmera, and 26, 48 and 55%, respectively at Rob Gebeya.Weeding once increased mean seed yields of faba bean by 25% on the average (35 and 17% at Welmera and Rob Gebeya, respectively compared to unweeded check. Seed yield was positively correlated with total biomass and number of pods per plant (r = 0.95*** and 0.75***, respectively at Welmera, and (r = 0.94*** and 0.55**, respectively at Rob Gebeya. The results of economic analysis indicated that the highest marginal rate of return was obtained from weeding once six weeks after crop emergence and application of 20 kg P ha-1, which is economically the most feasible alternative on Nitisols of central Ethiopian highlands.

  6. 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

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

    OpenAIRE

    Tatiely Gomes Bernardes; Pedro Marques da Silveira; Marcia Thaís de Melo Carvalho; Beáta Emöke Madari; Maria da Conceição Santana Carvalho

    2015-01-01

    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 ...

  8. Human chorionic gonadotrophin in early gestation induces growth of estrogenic ovarian follicles and improves primiparous sow fertility during summer.

    Science.gov (United States)

    Seyfang, Jemma; Langendijk, P; Chen, T Y; Bouwman, E; Kirkwood, R N

    2016-09-01

    Reduced summer farrowing rates may be due to inadequate corpora luteal (CL) support. Porcine CL become dependent on LH from 12 d of pregnancy and the embryonic estrogen signal for maternal recognition of pregnancy (MRP) is initiated at about 11-12 d after insemination. We hypothesised that injection of the LH analogue human chorionic gonadotropin (hCG) would induce growth of estrogenic follicles and, by mimicking the signal for MRP and stimulating progesterone secretion, increase primiparous sow fertility. In Experiment 1, during a 28 d lactation 53 mixed parity sows were full-fed either throughout lactation (n=16) or until 18 d and then feed restricted during the last 10 d of lactation (n=36). At 12 d after mating restrict-fed sows were injected with 1000IU hCG (n=17) or were not injected (n=19); the full-fed sows acted as non-treated positive controls. Transrectal ovarian ultrasound exams were performed on days 12, 16, 20, 24, and 28; blood samples were obtained on days 12, 14, and 15 for estradiol and progesterone assay. For Experiment 2, during the summer months primiparous sows received 1000IU hCG 12 d after mating (n=28) or were non-injected controls (n=27). Pregnancy status was determined at 28 d and sows allowed to go to term to determine farrowing rates and litter sizes. In Experiment 1, injection of hCG increased (Pfeeding level on wean-estrus interval, farrowing rate or subsequent litter size. In Experiment 2, hCG injection was associated with a higher pregnancy rate (Psow fertility during the summer months.

  9. Proteomic analysis of human follicular fluid in poor ovarian responders during in vitro fertilization.

    Science.gov (United States)

    Oh, Jae Won; Kim, Seul Ki; Cho, Kyung-Cho; Kim, Min-Sik; Suh, Chang Suk; Lee, Jung Ryeol; Kim, Kwang Pyo

    2017-03-01

    Poor ovarian response (POR) in controlled ovarian stimulation is often observed during in vitro fertilization and embryo transfer cycles and it is a major problem. A POR has been found to be related to several factors, including advanced age, high body mass index, and history of ovarian or pelvic surgery. However, it is difficult to predict POR, as there are no specific biomarkers known. In this study, we used quantitative proteomic analyses to investigate potential biomarkers that can predict poor response during in vitro fertilization based on follicular fluid samples. A total of 1079 proteins were identified using a high-resolution orbitrap mass spectrometer coupled online to a nanoflow-LC system. It is notable that 65 upregulated and 66 downregulated proteins were found to be functionally enriched in poor responders. We also validated these differentially expressed proteins using a triple-quadrupole mass spectrometer for quantification of targeted proteins. Of the differentially expressed proteins, three proteins (pregnancy zone protein, renin, and sushi repeat-containing protein SRPX) were regarded as statistically significant (p < 0.05). © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. 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.

  11. Effects of Film-Degraded Rice Controlled Release Fertilizer on the Nitrogen Uptake and Yield of the Hybrid Rice

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Field experiment was carried out to nitrogen release characteristics of rice controlled release fertilizer (RCRF) coated with natural and half natural high molecular materials, and to thereof effects on the nitrogen uptake and yield of early and late hybrid rice from 1999 to 2000, with urea as control.In experimental fields regardless of early and late seasons, the amount of N in the plants increased exponentially at the early growth stage (y=abx) and nonlinearly at the middle and late growth stages (y=a+bx+cx2).Rice controlled release fertilizer lengthened the exponential phase and increased the parameter -b/c during the nonlinear phase. Although the N amount of plants was less in rice controlled release fertilizer plots than in urea plots within 20 days after transplanting, at the heading and maturity stages, the N amount of plants in rice controlled release fertilizer plots was above two times greater than in the urea plots due to the higher N recovery, and the high absorption density of N in the nonlinear phase. Tillers pattern and achievement of the maximum tillering stage varied with fertilizer types. The maximum tillering stage in the urea plots occurred a week earlier than in the rice controlled release fertilizer plots. Yield sink size and potential sink size of the plants reflected the N absorption pattern and the amount of N in the plants. The yields of early and late rice with 90 kg N ha-1of rice controlled release fertilizer were respectively increased by 832.7 kg ha-1 and 412.8 kg ha-1 than those with 90 kg N ha-1 of urea, almost equivalent to the yield of early and late hybrid rice with 180 kg N ha-1 of urea.

  12. Effect of treatment with human chorionic gonadotropin on day 5 after timed artificial insemination on fertility of lactating dairy cows.

    Science.gov (United States)

    Nascimento, A B; Bender, R W; Souza, A H; Ayres, H; Araujo, R R; Guenther, J N; Sartori, R; Wiltbank, M C

    2013-05-01

    Reproductive management programs that synchronize ovulation can ovulate a smaller than normal follicle, potentially resulting in inadequate progesterone (P4) concentrations after artificial insemination (AI). Ovulation of the dominant follicle of the first follicular wave with human chorionic gonadotropin (hCG) treatment can produce an accessory corpus luteum and increase circulating P4 concentrations. This manuscript reports the results of 2 separate analyses that evaluated the effect of hCG treatment post-AI on fertility in lactating dairy cows. The first study used meta-analysis to combine the results from 10 different published studies that used hCG treatment on d 4 to 9 post-AI in lactating dairy cows. Overall, pregnancies per artificial insemination (P/AI) were increased 3.0% by hCG treatment post-AI [34% (752/2,213) vs. 37% (808/2,184); Control vs. hCG-treated, respectively]. The second study was a field research trial in which lactating Holstein cows (n=2,979) from 6 commercial dairy herds were stratified by parity and breeding number and then randomly assigned to one of 2 groups: control (no further treatment, n=1,519) or hCG [Chorulon i.m.: 2,000 IU (in 3 of the herds) or 3,300 IU (in 3 herds); n=1,460] on d 5 after a timed AI (ovulation synchronized with Ovsynch, Presynch-Ovsynch, or Double-Ovsynch). In a subset of cows, the hCG profile and P4 changes were determined. Treatment with hCG increased P4 (4.3 vs. 5.3 ng/mL on d 12). Pregnancies per AI were greater in cows treated with hCG (40.8%; 596/1,460) than control (37.3%; 566/1,519) cows. Interestingly, an interaction among treatment and parity was observed; primiparous cows had greater P/AI after hCG (49.7%; 266/535) than controls (39.5%; 215/544). In contrast, older cows receiving hCG (35.7%; 330/925) had similar P/AI to controls (36.0%; 351/975).Thus, targeted use of hCG on d 5 after TAI enhances fertility about 3.0% (based on meta-analysis) to 3.5% (based on our field trial). Surprisingly, this

  13. Fertility effects of abortion and birth control pill access for minors.

    Science.gov (United States)

    Guldi, Melanie

    2008-11-01

    This article empirically assesses whether age-restricted access to abortion and the birth control pill influence minors' fertility in the United States. There is not a strong consensus in previous literature regarding the relationship between laws restricting minors' access to abortion and minors' birth rates. This is the first study to recognize that state laws in place prior to the 1973 Roe v. Wade decision enabled minors to legally consent to surgical treatment-including abortion-in some states but not in others, and to construct abortion access variables reflecting this. In this article, age-specific policy variables measure either a minor's legal ability to obtain an abortion or to obtain the birth control pill without parental involvement. I find fairly strong evidence that young women's birth rates dropped as a result of abortion access as well as evidence that birth control pill access led to a drop in birth rates among whites.

  14. 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

  15. Human chorionic gonadotrophin priming for fertility treatment with in vitro maturation.

    Science.gov (United States)

    Reavey, Jane; Vincent, Katy; Child, Timothy; Granne, Ingrid E

    2016-11-16

    In vitro maturation (IVM) is a fertility treatment that involves the transvaginal retrieval of immature oocytes, and their subsequent maturation and fertilisation. Although the live birth rate is lower than conventional in vitro fertilisation (IVF) with ovarian stimulation, it is a useful treatment, as it avoids the risk of ovarian hyperstimulation syndrome (OHSS). Women with polycystic ovaries (PCO) or polycystic ovarian syndrome (PCOS) are at an increased risk of OHSS. Thus, IVM may be a more useful treatment in this patient group.Strategies to maximise the maturation rates of the immature oocytes are important. This review focuses on the administration of human chorionic gonadotrophin (hCG) prior to immature oocyte retrieval. To determine the effectiveness and safety of hCG priming in subfertile women who are undergoing IVM treatment in the context of assisted reproduction. We searched the following electronic databases up to 29 August 2016: Cochrane Gynaecology and Fertility Group Specialised Register of controlled trials, CENTRAL, MEDLINE, Embase, PsycINFO, and CINAHL. We also searched the trial registries ClinicalTrials.gov and WHO ICTPR to identify ongoing and registered trials. We sought recently published papers not yet indexed in the major databases, and reviewed the reference lists of reviews and retrieved studies as sources of potentially relevant studies. There were no language restrictions. We included randomised controlled trials (RCTs) that compared hCG priming with placebo or no priming in women undergoing IVM. We also included RCTs that compared different doses of hCG, or the timing of oocyte retrieval. The primary outcomes were live birth rate and miscarriage rate per woman randomised. Two review authors independently selected studies for inclusion, and with a third author, assessed risk of bias and extracted data. We contacted the original authors where data were missing. For dichotomous outcomes, we used the Mantel-Haenszel method to calculate

  16. [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.

  17. Proteomic analysis of heparin-binding proteins from human seminal plasma: a step towards identification of molecular markers of male fertility

    Indian Academy of Sciences (India)

    Vijay Kumar; Md Imtaiyaz Hassan; Anil Kumar Tomar; Tara Kashav; Jaya Nautiyal; Sarman Singh; Tej P Singh; Savita Yadav

    2009-12-01

    Glycosaminoglycans, especially heparin, are involved in various cell processes such as apoptosis, cell cycle control, platelet activation, capacitation, acrosome reaction and sperm decondensation. Heparin-binding proteins (HBPs) are essential constituents of human seminal fluid, which bind to sperm lipids containing the phosphorylcholine group and mediate the fertilization process. We utilized a proteomic set-up consisting of affinity chromatography, isoelectric focusing (IEF) coupled with matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI TOF/MS) for protein analysis of human HBPs. We resolved 70 different spots on two-dimensional (2-D) gel and subsequently identified these proteins. Forty different types of proteins were identified. Functional analysis revealed that 38% of the proteins belonged to the enzyme category, 20% were involved in RNA processing and transcription, 18% in structure and transport function, and 16% in cell recognition and signal transduction. We also identified 8% of proteins with unknown functions, although their expression in seminal fluid has been documented. Proteins of seminal fluid that bind heparin may be directly involved in sperm capacitation and acrosome reaction (AR), which are the two critical steps for fertilization. This information on HBPs would be useful for identifying potential biomarkers of fertility in the near future.

  18. Release Characteristics of Different N Forms in an Uncoated Slow/Controlled Release Compound Fertilizer

    Institute of Scientific and Technical Information of China (English)

    DONG Yan; WANG Zheng-yin

    2007-01-01

    This study examined the release characteristics of different N forms in an uncoated slow/controlled-release compound fertilizer (UCRF) and the N uptake and N-use efficiency by rice plants. Water dissolution, soil leaching, and pot experiments were employed. The dynamics of N release from the UCRF could be quantitatively described by three equations: the first-order kinetics equation [Nt = N0 (1-e-kt)], Elovich equation (Nt = a + blnt), and parabola equation (Nt = a + bt0.5), with the best fitting by the first-order kinetics equation for different N (r= 0.9569**-0.9999**). The release potentials (N0 values estimated by the first-order kinetics equation) of different N in the UCRF decreased in the order of total N > DON > urea-N > NH4+-N > NO3--N in water, and total N > NH4+-N > DON > urea-N > NO3--N in soil, respectively,being in accordance with cumulative amounts of N release. The constants of N release rate (k values and b values) for different N forms were in decreasing order of total N > DON > NH4+-N > NO3--N in water, whereas the k values were urea-N >DON > NH4+-N > total N > NO3--N, and the b values were total N > NH4+-N > DON > NO3--N > urea-N in soil. Compared with a common compound fertilizer, the N-use efficiency, N-agronomy efficiency, and N-physiological efficiency of the UCRF were increased by 11.4%, 8.32 kg kg-1, and 5.17 kg kg-1, respectively. The ratios of different N to total N in the UCRF showed significant correlation with N uptake by rice plants. The findings showed that the first-order kinetics equation [Nt=N0(1-e-kt)] could be used to describe the release characteristics of different N forms in the fertilizer. The UCRF containing different N forms was more effective in facilitating N uptake by rice compared with the common compound fertilizer containing single urea-N form.

  19. 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

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

    Science.gov (United States)

    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

  1. [Effects of controlled release nitrogen fertilizer application on dry matter accumulation and nitrogen balance of summer maize].

    Science.gov (United States)

    Si, Dong-Xia; Cui, Zhen-Ling; Chen, Xin-Ping; Lü, Fu-Tang

    2014-06-01

    Effects of four controlled release nitrogen (N) fertilizers, including two kinds of polyester coated urea (Ncau, CRU) and phosphate (NhnP) and humic acid (NhnF) coated urea on assimilates accumulation and nitrogen balance of summer maize were investigated in a mode of one-time fertilization at the regional N recommended rate. The results showed that the N release curves of the two controlled release fertilizers CRU and Ncau matched well with the summer maize N uptake. Compared with the regional N recommendation rate, CRU could increase maize yield by 4.2% and Ncau could maintain the same yield level. CRU significantly increased the dry matter accumulation rate after anthesis of summer maize, but Ncau markedly increased the dry matter accumulated ratio before anthesis. Meanwhile, CRU could reduce the apparent N losses by 19 kg N x hm(-2) in the case of large precipitation. However, NhnF and NhnP caused the yield losses by 0.1%-8.9%, and enhanced the apparent N losses. Therefore, both CRU and Ncau with one-time fertilization could be a simplified alternative to the "total control, staging regulation" fertilization technique at the regional N recommended rate for summer maize production.

  2. SOLID POLYMERIC MATRIX BASED ON CHITOSAN AND XANTHAN FOR CONTROLLED RELEASE OF FERTILIZERS

    Directory of Open Access Journals (Sweden)

    Mariana A. Melaj

    2012-03-01

    Full Text Available The main purpose of this work was to optimize the preparation conditions of solid polymeric matrix based on Chitosan and Xanthan, to be used in the controlled release of fertilizers. KNO3 was chosen as model agrochemical to be released. Both individual polymers and the Xanthan:Chitosan complex are biocompatible, leaving a residue on the soil which is non-toxic. The influence of different variables on the release pattern was studied: the type of polymer, the pressed conditions of the tablets and the presence of a drug-free polymeric coating. The polymer that presented a more promising release profile was Xanthan. The compression pressure applied to prepare the tablets was a more relevant variable than the compression time, in its effect on the kinetics of release. It was determined that the coating of the polymer matrix with crosslinked chitosan-glutaraldehyde allows getting a larger release time.

  3. Synthesis and Performance of Polyurethane Coated Urea as Slow/controlled Release Fertilizer

    Institute of Scientific and Technical Information of China (English)

    LI Qingshan; WU Shu; RU Tiejun; WANG Limin; XING Guangzhong; WANG Jinming

    2012-01-01

    Polyurethane coated urea slow/controlled release fertilizer was prepared based on urea granules,isocyanate,polyols and paraffin.Isocyanate reacted with polyols to synthesize the polyurethane skin layer on urea granules surface.Paraffin serves as a lubricant during syntheses of polyurethane skin layers.The structure and nutrient release characteristics of the polyurethane skin layers were investigated by FTIR,SEM and TG.Urea nitrogen slow-release behavior of the polyurethane coated urea was tested.The experimental results indicated that compact and dense polyurethane skin layers with a thickness of 10-15 μm were formed on urea surface,the urea nitrogen slow-release time can reach 40-50 days.Paraffin proves to play a key role in inhibiting water to penetrate into urea,but excessive addition would decrease the polyurethane crosslinking density.

  4. 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

  5. Optimal control for predicting customized drug dosage for superovulation stage of in vitro fertilization.

    Science.gov (United States)

    Yenkie, Kirti M; Diwekar, Urmila

    2014-08-21

    in vitro fertilization (IVF) is one of the most highly pursued assisted reproductive technologies (ART) worldwide. IVF procedure is divided into four stages: Superovulation, Egg-retrieval, Insemination/Fertilization and Embryo transfer. Among these superovulation is the most crucial stage since it involves external injection of hormones to stimulate development and maturation of multiple follicles or oocytes. Although numerous advancements have been made in IVF procedures, little attention has been given to modifying the existing protocols based on a 'patient specific' predictive model. A model for follicle growth and number change as a function of the injected hormones and patient characteristics has been developed and validated for data available on 50 superovulation cycles. The model has 9 patient specific parameters which can be determined from the initial 2 days of observation and can help in projecting the superovulation outcome for the ongoing cycle. Based on this model, the dosage of the hormones to stimulate multiple ovulation or follicle growth is predicted by using the theory of optimal control. The objective of successful superovulation is to obtain maximum number of mature oocytes/follicles within a particular size range. Using the mathematical model of follicle growth dynamics and optimal control theory, optimal dose and frequency of medication customized for each patient (n=5) is predicted for obtaining the desired result. The results indicate a better final day follicle size distribution when the dosage of the hormones is varied by some amounts as compared to the actual dosage given to the patient in the existing cycles. This ensures a better success rate for the superovulation cycles and reduces the costs of excess medication and daily monitoring. The idea is to provide the medical practitioners with a guideline for planned treatment, for a procedure currently based on trial and error in order to get better success rates. Copyright © 2014 Elsevier

  6. Biology of male fertility control: an overview of various male contraceptive approaches.

    Science.gov (United States)

    Tulsiani, D R; Abou-Haila, A

    2015-04-01

    The population of our planet continues to grow at an alarming rate. If the growth continues at the present rate, the estimated current world population of about seven billion is expected to double in the next forty years. Accumulated data from surveys by the United Nations Population Control Division suggest that a majority of today's young men in many countries are willing to have fewer children than their parents did. However, the contraceptive options available to them have not changed in several decades. In spite of the general agreement that men, like women, must take full responsibility of their fertility, the availability of safe, reversible and affordable contraceptives for men have lagged behind because of the complexity of the science of the male reproductive system. Thus, the contraceptive needs of millions of men/couples go unmet every single day and results in millions of unwanted pregnancies. In this article, we intend to discuss new hormonal and non-hormonal contraceptive approaches that are at various stages of research and development and may someday provide new contraceptives for men. In addition, we intend to discuss many details of three safe, effective, affordable and reversible vas-based approaches that are inching closer to being approved for use by millions of men in multiple countries. Finally, our intention is to discuss the male contraceptive pill that will soon be available to men only in Indonesia. The availability of these male contraceptives will allow both men and women to take full control of their fertility and participate in slowing down the growth of world population.

  7. Renal and Hepatic Functions after A Week of Controlled Ovarian Hyperstimulation during In Vitro Fertilization Cycles

    Directory of Open Access Journals (Sweden)

    Romito Ilaria

    2017-01-01

    Full Text Available Background: One the main aspects of in vitro fertilization (IVF cycle is to avoid any possible systemic damage on women undergoing a controlled ovarian hyperstimulation (COH. The aim of this work is to evaluate renal and hepatic function blood tests in patients undergoing controlled ovarian hyperstimulation during IVF cycles. Materials and Methods: We performed a prospective cohort analysis. All patients re- ceived a long stimulation protocol with gonadotropin-releasing hormone (GnRH analogues by daily administration, since the twenty-first day of the previous ovarian cycle followed by COH with recombinant follicle-stimulating hormone (FSH. The daily dose of exogenous gonadotropins for every single patient was modified according to her follicular growth. The oocytes were retrieved during the oocyte pick up and fertilized by standard procedures of intracytoplasmic sperm injection (ICSI. The blood samples to evaluate renal and hepatic functions were taken at the 7th day of ovarian stimulation. Results: We enrolled 426 women aged between 19 and 44 years, with a mean body mass index (BMI of 24.68 Kg/m2. The mean value of blood urea nitrogen was 14 ± 3.16 mg/ dl, creatinine: 1 ± 0.45 mg/dl, uric acid: 4 ± 1.95 mg/dl, total proteins: 7 ± 3.93 mg/dl, aspartate aminotransferase: 18 ± 6.29 mU/ml, alanine aminotransferase: 19 ± 10.41 mU/ ml, alkaline phosphatase: 81 ± 45.25 mU/ml, total bilirubin 1 ± 0.35 mg/dL. All of the results were considered as a normal range following the Medical Council of Canada. Conclusion: Our data suggest that, unlike ovarian hyperstimulation syndrome (OHSS, COH patients did not show any alteration to renal and hepatic functions.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    Kolk, Martin; Cownden, Daniel; Enquist, Magnus

    2014-03-22

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

  10. 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)

  11. Institutionalizing fertility management/human sexuality training in Colombian nursing schools.

    Science.gov (United States)

    Gaffikin, L; Prada, E; Santamaria, A; McGrath, J; de Castro Buffington, S

    1995-12-01

    While there is no universally applied definition of the terms, 'institutionalization', 'capacity', 'capability' and 'commitment' have been suggested as subindicators of a self-sustained program. This paper describes efforts to measure these terms in the context of a fertility management/human sexuality (FM/HS) education program for student nurses in Colombia. Interviews with 19 school deans formed the basis of measuring progress towards institutionalization. All the deans supported the idea of having FM/HS instruction, although resource commitment to effectively carry out the instruction varied. Focus groups with professors from participating schools provided insights into the effect of the project on both the students and course teachers. Professors found that students who had taken the course were more effective FM/HS counselors in later practical courses. Responses from interviews with a random sample of students who had or had not attended the course were compared to assess the effect of the course on the nursing students. Although attitudes between the two groups did not differ significantly, knowledge levels about FM/HS were significantly higher among nursing students who had attended the course. In general, the results indicate that the participatory educational approach used in teaching the FM/HS topics was effective in sensitizing both students and teachers to this subject area.

  12. [Effects of applying controlled release fertilizers on N2O emission from a lateritic red soil].

    Science.gov (United States)

    Du, Ya-qin; Zheng, Li-xing; Fan, Xiao-lin

    2011-09-01

    Static closed chamber technique and contrast method were adopted to study the effects of three coated compound fertilizers (N:P2O5:K2O = 19:8.6:10.5, high N; 14.4:14.4:14.4, balanced NPK; and 12.5:9.6:20.2, high K) on the NO2O emission from a lateritic red soil under the condition of no crop planting, taking uncoated compound fertilizers (N:P2O5:K2O = 20:9:11, high N; 15:15:15, balanced NPK; and 13:10:21, high K) as the contrasts. Different formula of fertilizer NPK induced significant difference in the N2O emission. Under the application of uncoated compound fertilizers, the cumulative N2O emission was in the order of balanced NPK > or = high N > high K. Applying coated compound fertilizers decreased the N2O emission significantly, and the emission amount under the application of high N, balanced NPK, and high K was 34.4%, 30.5%, and 89.3% of the corresponding uncoated compound fertilizers, respectively. Comparing with the application of uncoated compound fertilizers, applying coated compound fertilizers also decreased the daily N2O flux significantly, and delayed and shortened the N2O peak, suggesting that coated fertilizers could reduce soil nitrogen loss and the global warming potential induced by N2O emission.

  13. Initial substrate moisture content and storage temperature affect chemical properties of bagged substrates containing controlled release fertilizer

    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...

  14. 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 wo

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

    NARCIS (Netherlands)

    Begall, Katia; Mills, Melinda

    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 wo

  16. Toilet compost and human urine used in agriculture: fertilizer value assessment and effect on cultivated soil properties.

    Science.gov (United States)

    Sangare, D; Sou Dakoure, M; Hijikata, N; Lahmar, R; Yacouba, H; Coulibaly, L; Funamizu, N

    2015-01-01

    Toilet compost (TC) and human urine are among natural fertilizers, which raise interest due to their double advantages to combine sanitation and nutrient recovery. However, combination of urine and TC is not so spread probably because the best ratio (urine/TC) is still an issue and urine effect on soil chemical properties remains poorly documented. This study aims to determine the best ratio of urine and TC in okra cultivation, by targeting higher fertilization effect combined with lower impact on soil chemical properties. Based on Nitrogen requirement of okra, seven treatments were compared: (T0) no fertilizer, (T1) chemical fertilizer (NPK: 14-23-14), (T2) 100% urine, (T3) 100% TC, (T4) ratio of 75% urine+25% TC, (T5) 50% urine+50% TC and (T6) 25% urine+75% TC. Results indicated that T4 (75% urine+25% TC) gave the highest plant height and yield. In contrast, T2 (100% urine) gave the lowest results among all treatments, indicating toxicity effects on plant growth and associated final yield. Such toxicity is confirmed by soil chemical properties at T2 with soil acidification and significant increase in soil salinity. In contrast, application of urine together with TC mitigates soil acidification and salinity, highlighting the efficiency of urine and TC combination on soil chemical properties. However, further investigation is necessary to refine better urine/TC ratio for okra production.

  17. A study of the effect of the FertilMate™ scrotum cooling patch on male fertility. SCOP trial (scrotal cooling patch - study protocol for a randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Osman M

    2012-04-01

    Full Text Available Abstract Background Male infertility is a significant contributor to the need for fertility treatment. Treatment currently involves correcting any identifiable adverse lifestyle factors in men with suboptimal sperm parameters, and if these measures are unsuccessful, assisted conception is offered, which can be quite expensive. Raised scrotal temperature is one of the least studied but easily corrected risk factors for male infertility. In a recent review of the literature, sperm count, motility and morphology improved with scrotal cooling devices. The devices used to achieve testicular cooling were, however, not practical for day-to-day use. A potentially more practical device for scrotal cooling has recently been developed. The Babystart® FertilMate™ Scrotum Cooling Patch is a hydrogel pad which allows for comfortable application. The aims of this study were to investigate whether exposing the scrotum to lower temperatures by means of these new patches could improve semen parameters, thereby improving fertility, and to assess the feasibility of a clinical trial. Methods/design This is a randomised controlled trial set in a university teaching hospital in the United Kingdom. The proposed sample size was 40 men with mild, moderate or severe oligoasthenospermia, of whom 20 would be randomised to wearing the scrotum cooling patch for 90 days and 20 men would be acting as controls and not wearing the patches. The primary outcome measure was the change in sperm concentration. Secondary outcome measures included the change in sperm volume, motility and morphology; endocrine parameters; metabolomic biomarkers; testicular volume and blood flow. Reasons for dropping out and non-compliance were also going to be noted and reported. Discussion The study started recruiting in October 2011 and as of November 2011 four men had been consented and were participating in the study. No operational challenges had been encountered at the time of the submission

  18. 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.

  19. Ecological basis for fertility control in the house mouse (Mus domesticus) using immunocontraceptive vaccines.

    Science.gov (United States)

    Singleton, G R; Farroway, L N; Chambers, L K; Lawson, M A; Smith, A L; Hinds, L A

    2002-01-01

    Laboratory studies confirm the potential for fertility control in the house mouse Mus domesticus using mouse cytomegalovirus (MCMV) as a vector for an immunocontraceptive vaccine. This article presents an overview of key results from research in Australia on enclosed and field populations of mice and the associated epidemiology of MCMV. The virus is geographically widespread in Australia. It also persists in low population densities of mice, although if population densities are low for at least a year, transmission of the virus is sporadic until a population threshold of approximately 40 mice ha(-1) is reached. The serological prevalence of MCMV was high early in the breeding season of four field populations. Enclosure studies confirm that MCMV has minimal impact on the survival and breeding performance of mice and that it can be transmitted to most adults within 10-12 weeks. Other enclosure studies indicate that about two-thirds of females would need to be sterilized to provide effective control of the rate of growth of mouse populations. If this level is not maintained for 20-25 weeks after the commencement of breeding, the mouse population can compensate through increased recruitment per breeding female. The findings from this series of descriptive and manipulative population studies of mice support the contention that MCMV would be a good carrier for an immunocontraceptive vaccine required to sustain female sterility levels at or above 65%.

  20. Review on materials & methods to produce controlled release coated urea fertilizer.

    Science.gov (United States)

    Azeem, Babar; KuShaari, KuZilati; Man, Zakaria B; Basit, Abdul; Thanh, Trinh H

    2014-05-10

    With the exponential growth of the global population, the agricultural sector is bound to use ever larger quantities of fertilizers to augment the food supply, which consequently increases food production costs. Urea, when applied to crops is vulnerable to losses from volatilization and leaching. Current methods also reduce nitrogen use efficiency (NUE) by plants which limits crop yields and, moreover, contributes towards environmental pollution in terms of hazardous gaseous emissions and water eutrophication. An approach that offsets this pollution while also enhancing NUE is the use of controlled release urea (CRU) for which several methods and materials have been reported. The physical intromission of urea granules in an appropriate coating material is one such technique that produces controlled release coated urea (CRCU). The development of CRCU is a green technology that not only reduces nitrogen loss caused by volatilization and leaching, but also alters the kinetics of nitrogen release, which, in turn, provides nutrients to plants at a pace that is more compatible with their metabolic needs. This review covers the research quantum regarding the physical coating of original urea granules. Special emphasis is placed on the latest coating methods as well as release experiments and mechanisms with an integrated critical analyses followed by suggestions for future research. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Does human papillomavirus infection do harm to in-vitro fertilization outcomes and subsequent pregnancy outcomes?

    Institute of Scientific and Technical Information of China (English)

    YANG Rui; WANG Ying; QIAO Jie; LIU Ping; GENG Li; GUO Yan-li

    2013-01-01

    Background Some studies suggested that human papillomavirus (HPV) infection could reduce the clinical pregnancy rate and double the spontaneous abortion rate compared with non-infected women after in-vitro fertilization and embryo transfer (IVF-ET).But some other studies showed there was no difference between HPV infected and non-infected groups of ART outcomes.The role of HPV infection in infertile women undergoing IVF treatments has been a controversial issue which this article attempts to investigate.Methods This is a retrospective analysis of 3880 infertile women undergoing IVF treatment at Peking University Third hospital reproductive medical center in 2008.Patients with abnormal thin-layer preparation cytologic test (TCT) results who underwent fresh cycle embryo transfer were divided into an HPV positive group (n=56) and an HPV negative group (n=56).The clinical parameters were compared (using Student's t-test and chi-squared test).Univariate and multivariate analyses were taken to see if HPV infection affects the clinical pregnancy rate.Results Of the 3880 cases 157 had TCT abnormality (4.0%).Of the 149 patients who had HPVtest results,112 women (81.2%) received a fresh cycle embryo transfer.Each group had 56 cases.The patients were of similar age and BMI,basic hormone levels,and infertile factors were similar.The gonadotropin use,oocyte retrieval number,clinical pregnancy rate,abortion rate and newborn condition were all similar between groups.Analyses showed neither HPV infection nor HPV hybrid capture (HC) Ⅱ results affected clinical pregnancy rate after IVF treatments,but the FSH level did.Conclusion HPV positivity did not appear to impact assisted reproductive technology (ART) success."Extensive treatment" for HPV before IVF was not recommended because treatment time will increase age and reduce ovarian function,which will lead to inferior IVF outcomes.

  2. Effects of a Control Release Nitrogen Fertilizer and Thinning on the Nitrogen Dynamics of a Mid-Rotation Loblolly Pine Stand in the Piedmont of Virginia

    OpenAIRE

    Elliot, James Robertson

    2006-01-01

    Nitrogen deficiency is characteristic of many mid-rotation loblolly pine (Pinus taeda L.) plantations in the Piedmont region of the southeastern USA. Fertilization with urea is the most common method used to correct this deficiency. Previous studies show that urea fertilization produces a rapid pulse of available nitrogen (N) with only a portion being utilized by plantation trees. Controlled release fertilizers release available N more slowly over a longer period of time and therefore may ...

  3. Effects of a Control Release Nitrogen Fertilizer and Thinning on the Nitrogen Dynamics of a Mid-Rotation Loblolly Pine Stand in the Piedmont of Virginia

    OpenAIRE

    Elliot, James Robertson

    2006-01-01

    Nitrogen deficiency is characteristic of many mid-rotation loblolly pine (Pinus taeda L.) plantations in the Piedmont region of the southeastern USA. Fertilization with urea is the most common method used to correct this deficiency. Previous studies show that urea fertilization produces a rapid pulse of available nitrogen (N) with only a portion being utilized by plantation trees. Controlled release fertilizers release available N more slowly over a longer period of time and therefore may ...

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

    Science.gov (United States)

    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.

  5. Controlled release fertilizer and container volumes in the production of Parapiptadenia rigida (Benth. Brenan seedlings

    Directory of Open Access Journals (Sweden)

    Ezequiel Gasparin

    2015-10-01

    Full Text Available Growing demand for native tree seedlings will require improvements in quality standards of production processes through the use of more efficient cultivation techniques. This study evaluated the effects of different doses of controlled release fertilizer (CRF and different container volumes in the production of Parapiptadenia rigida seedlings. We examined the effects of five different concentrations (0, 3, 6, 9 and 12 g L-1 substrate of CRF (18-5-9 NPK and three different container volumes (50, 110 and 180 cm3 on seedling height (H and collar diameter (CD measured monthly for seven months and then calculated H/CD ratios. After 210 days of growth, the dry masses of the aerial portions, root systems, and total masses were determined, as well as the concentrations of macro- and micronutrients in the aerial portions of the seedlings. In general, the dose 9 g L-1 substrate combined with the 180 cm3 cultivation tubes demonstrated the best results in terms of the morphological variables analyzed, resulting in consistent quality seedlings for field planting.

  6. Environmental control of biological rhythms: effects on development, fertility and metabolism.

    Science.gov (United States)

    Amaral, F G; Castrucci, A M; Cipolla-Neto, J; Poletini, M O; Mendez, N; Richter, H G; Sellix, M T

    2014-09-01

    Internal temporal organisation properly synchronised to the environment is crucial for health maintenance. This organisation is provided at the cellular level by the molecular clock, a macromolecular transcription-based oscillator formed by the clock and the clock-controlled genes that is present in both central and peripheral tissues. In mammals, melanopsin in light-sensitive retinal ganglion cells plays a considerable role in the synchronisation of the circadian timing system to the daily light/dark cycle. Melatonin, a hormone synthesised in the pineal gland exclusively at night and an output of the central clock, has a fundamental role in regulating/timing several physiological functions, including glucose homeostasis, insulin secretion and energy metabolism. As such, metabolism is severely impaired after a reduction in melatonin production. Furthermore, light pollution during the night and shift work schedules can abrogate melatonin synthesis and impair homeostasis. Chronodisruption during pregnancy has deleterious effects on the health of progeny, including metabolic, cardiovascular and cognitive dysfunction. Developmental programming by steroids or steroid-mimetic compounds also produces internal circadian disorganisation that may be a significant factor in the aetiology of fertility disorders such as polycystic ovary syndrome. Thus, both early and late in life, pernicious alterations of the endogenous temporal order by environmental factors can disrupt the homeostatic function of the circadian timing system, leading to pathophysiology and/or disease. © 2014 British Society for Neuroendocrinology.

  7. Molecular Control of Male Reproductive Development and Pollen Fertility in Rice

    Institute of Scientific and Technical Information of China (English)

    Jing-Xin Guo; Yao-Guang Liu

    2012-01-01

    Anther development and male fertility are essential biological processes for flowering plants and are important for crop seed production.Genetic manipulation of male fertility/sterility is critical for crop hybrid breeding.Rice (Oryza sativa L.) male sterility phenotypes,including genic male sterility,hybrid male sterility,and cytoplasmic male sterility,are generally caused by mutations of fertility-related genes,by incompatible interactions between divergent allelic or non-allelic genes,or by genetic incompatibilities between cytoplasmic and nuclear genomes.Here,we review the recent advances in the molecular basis of anther development and male fertility-sterility conversion in specific genetic backgrounds,and the interactions with certain environmental factors.The highlighted findings in this review have significant implications in both basic studies and rice genetic improvement.

  8. Fertilization practices and soil variations control nitrogen oxide emissions from tropical sugar cane

    Science.gov (United States)

    Matson, P. A.; Billow, C.; Hall, S.; Zachariassen, J.

    1996-08-01

    Nitrogen (N) fertilization of agricultural systems is thought to be a major source of the increase in atmospheric N2O; NO emissions from soils have also been shown to increase due to N fertilization. While N fertilizer use is increasing rapidly in the developing world and in the tropics, nearly all of our information on gas emissions is derived from studies of temperate zone agriculture. Using chambers, we measured fluxes of N2O and NO following urea fertilization in tropical sugar cane systems growing on several soil types in the Hawaiian Islands, United States. On the island of Maui, where urea is applied in irrigation lines and soils are mollisols and inceptisols, N2O fluxes were elevated for a week or less after fertilization; maximum average fluxes were typically less than 30 ng cm-2 h-1. NO fluxes were often an order of magnitude less than N2O. Together, N2O and NO represented from 0.03 to 0.5% of the applied N. In fields on the island of Hawaii, where urea is broadcast on the surface and soils are andisols, N2O fluxes were similar in magnitude to Maui but remained elevated for much longer periods after fertilization. NO emissions were 2-5 times higher than N2O through most of the sampling periods. Together the gas losses represented approximately 1.1-2.5% of the applied N. Laboratory studies indicate that denitrification is a critical source of N2O in Maui, but that nitrification is more important in Hawaii. Experimental studies suggest that differences in the pattern of N2O/NO and the processes producing them are a result of both carbon availability and placement of fertilizer and that the more information-intensive fertilizer management practice results in lower emissions.

  9. Control of estrus and ovulation: Fertility to timed insemination of gilts and sows.

    Science.gov (United States)

    De Rensis, F; Kirkwood, R N

    2016-10-01

    It is possible to control follicular development in gilts and sows with the use of hormones including the progestogen altrenogest, GnRH, eCG, hCG, and porcine luteinizing hormone (pLH). These hormones can be used to develop protocols for control of estrus with artificial insemination (AI) timed to estrus detection (timed artificial insemination; TAI) or to control estrus and ovulation with insemination at a fixed time without the requirement of estrus detection (fixed-timed artificial insemination; FTAI). In cyclic gilts, double TAI after protocols based on altrenogest and eCG plus hCG administration can achieve a 70% of farrowing rate. Valuable results can be obtained in weaned sows by the utilization of protocols based on eCG administration at weaning and then GnRH or pLH at estrus onset followed by single or double TAI. In cyclic gilts, single or double FTAI regardless of estrus expression can be applied after protocols based on altrenogest administration followed by eCG and then GnRH, hCG, or pLH some hours later; farrowing rates are similar to control animals inseminated at estrus detection. With sows, a protocol based on eCG administration at weaning and hCG, GnRH, or pLH some hours later followed by single or double FTAI can give fertility rates comparable to control animal inseminated at estrus. Most recently, injection or vaginal deposition of GnRH 96 hours after weaning followed by a single FTAI 24 to 30 hours later is resulting in reproductive performance not different to animals subject to multiple inseminations after natural estrus. It is possible to apply FTAI in lactating sows. The protocols are based on eCG during lactation followed by hCG and FTAI. These protocols will induce ovulation during lactation, but pregnancy rates are reduced. However, in the future, a better knowledge on the effect of hormone administration on follicular dynamics during lactation may allow the development of more effective protocols.

  10. Environmental friendly nitrogen fertilization

    Institute of Scientific and Technical Information of China (English)

    Avi; Shaviv

    2005-01-01

    With the huge intensification of agriculture and the increasing awareness to human health and natural resources sustainability, there was a shift towards the development of environmental friendly N application approaches that support sustainable use of land and sustain food production.The effectiveness of such approaches depends on their ability to synchronize plant nitrogen demand with its supply and the ability to apply favored compositions and dosages of N-species.They are also influenced by farming scale and its sophistication, and include the following key concepts: (i) Improved application modes such as split or localized ("depot") application; (ii) use of bio-amendments like nitrification and urease inhibitors and combinations of (i) and (ii); (iii) use of controlled and slow release fertilizers; (iv) Fertigation-fertilization via irrigation systems including fully automated and controlled systems; and (v) precision fertilization in large scale farming systems. The paper describes the approaches and their action mechanisms and examines their agronomic and environmental significance. The relevance of the approaches for different farming scales, levels of agronomic intensification and agro-technical sophistication is examined as well.

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

    Directory of Open Access Journals (Sweden)

    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.

  12. 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.

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

    NARCIS (Netherlands)

    Just, E.M.|info:eu-repo/dai/nl/304835196

    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

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

    NARCIS (Netherlands)

    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 I

  15. Utilization of Human Urine as Fertilizer with Magnesium Oxide (MgO, Zeolite and Activated Carbon as Absorbent

    Directory of Open Access Journals (Sweden)

    Hijrah Purnama Putra

    2014-01-01

    Full Text Available Urine is residual fluid excreted by kidneys through urinary tract to outside of the human body, to maintain homeostasis of fluid in the body. Normally urine still contains high amount of nitrogen, which is 87%, phosphor 50%, potassium 54% and low bacterial content. With these contents urine potentially becomes organic fertilizer rich with nitrogen, phosphor and potassium contents and is beneficial to plants. However, until today the utilization or urine in Indonesia is very low. The urine produced is dispose with feces in toilets. This study aimed to utilize urine as solid organic fertilizer using magnesium oxide (MgO, zeolite, and actived carbon as absorbents of ammonium and phosphor. The study started with collecting urine, time variations of urine storage were 24; 48 and 72 hours, and urine was mixed with water as an assumption that urine mixes with water when flushed in urinals. The result showed effectiveness of optimum urine absorption in urine stored for 48 hours by adding 8 gram MgO, producing ammonium and phosphor contents 56.100 ppm and 3.610 ppm, respectively. From environmental perspective, utilization of urine as organic fertilizer was applicable because it satisfied the ecological principle of sanitation to prevent soil pollution, ground and surface water pollution and its utilization as agricultural resources.

  16. 缓/控释肥料的研究进展%Research development of slow/controlled release fertilizers

    Institute of Scientific and Technical Information of China (English)

    牛永生; 明大增; 李志祥; 李沪萍

    2012-01-01

    The basic connotation of slow/controlled release fertilizer at home and abroad and its research background and progress are presented. The recent research status of integument of slow/controlled release fertilizer is summarized. The principle of increase production is described briefly, and the key points of study and development prospect are overviewed.%介绍了缓/控释肥料的基本内涵和国内外的研究背景和进展,对国内外最新研究的缓/控释肥料包裹层进行了综述.简单说明了缓/控释肥料的增产原理,对缓/控释肥料的研究重点和发展前景进行了展望.

  17. Random-start controlled ovarian stimulation for emergency fertility preservation in a patient with myelodysplastic syndrome: a case report

    Directory of Open Access Journals (Sweden)

    H. Cai

    2016-01-01

    Full Text Available This study reports a case of a gonadotropin-releasing hormone agonist trigger in a young female with myelodysplastic syndrome (MDS who underwent fertility preservation using random-start controlled ovarian stimulation. This method involves the stimulation of the ovary regardless of a patient's menstrual-cycle phase. A review of the related literature is also provided. A 17-year-old patient was diagnosed with MDS and required initiation of peripheral blood stem cell transplantation within a maximum of 3 weeks and was in the luteal phase of the menstrual cycle when the possibility of attempting preservation of fertility was presented to her. She opted for a random-start controlled ovarian stimulation with gonadotropins. With successful hemorrhagic prophylaxis, 17 oocytes were retrieved including 10 mature and 7 immature oocytes. Of the immature oocytes, 3 were successfully matured in vitro and a vitrification protocol was used to freeze the 13 mature oocytes.

  18. Reaction-Multi Diffusion Model for Nutrient Release and Autocatalytic Degradation of PLA-Coated Controlled-Release Fertilizer

    Directory of Open Access Journals (Sweden)

    Sayed Ameenuddin Irfan

    2017-03-01

    Full Text Available A mathematical model for the reaction-diffusion equation is developed to describe the nutrient release profiles and degradation of poly(lactic acid (PLA-coated controlled-release fertilizer. A multi-diffusion model that consists of coupled partial differential equations is used to study the diffusion and chemical reaction (autocatalytic degradation simultaneously. The model is solved using an analytical-numerical method. Firstly, the model equation is transformed using the Laplace transformation as the Laplace transform cannot be inverted analytically. Numerical inversion of the Laplace transform is used by employing the Zakian method. The solution is useful in predicting the nutrient release profiles at various diffusivity, concentration of extraction medium, and reaction rates. It also helps in explaining the transformation of autocatalytic concentration in the coating material for various reaction rates, times of reaction, and reaction-multi diffusion. The solution is also applicable to the other biodegradable polymer-coated controlled-release fertilizers.

  19. 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.

  20. [Effect of controlled release fertilizer on nitrous oxide emission from paddy field under plastic film mulching cultivation].

    Science.gov (United States)

    Zhang, Yi; Lü, Shi-Hua; Ma, Jing; Xu, Hua; Yuan, Jiang; Dong, Yu-Jiao

    2014-03-01

    A field experiment was conducted to assess the effect of controlled release fertilizer on N2O emission in paddy field under plastic film mulching cultivation (PM) with water-saving irrigation. Results showed that in the rice growing season, cumulative N2O emissions from the plots applied with urea (PM+U) and with controlled release fertilizer (PM+CRF) were (38.2 +/- 4.4) and (21.5 +/- 5.2) mg N x m(-2), respectively. The N2O emission factors were 0.25% and 0.14% in the treatments PM+U and PM+CRF, respectively. The controlled release fertilizer decreased the total N2O emission by 43.6% compared with urea, of which 49.6% was reduced before the drying period. It also reduced the peak of N2O emission by 52.6%. However, it did not affect soil microbial biomass N and soil NH(4+)-N content at any rice growing stage, and grain yield either. No significant correlation was observed between N2O flux and soil Eh or soil temperature at the depth of 5 cm.

  1. Cytokines in Human Seminal Plasma and Their Effect on Male Fertility

    Institute of Scientific and Technical Information of China (English)

    Snje(z)ana (Z)idovec; Sanja Vujisi(c)

    2005-01-01

    Cytokines are a heterogeneous group of peptides that play an important role in intercellular communication, regulation of innate and specific immunity, hematopoiesis,interaction between the immune system and neuroendocrine network as well as in reproduction and development. Seminal plasma provides an immunological environment for the semen and contains important biological response mediators. Numerous studies investigated the presence of various cytokines in the seminal plasma and tried to correlate cytokine levels with sperm quality and male fertility. However, the pathophysiological significance of seminal cytokines in sperm function is still not completely understood. The purpose of this review is to provide a brief summary of the extensive literature dealing with cytokines in the seminal plasma and to discuss the contribution of local cytokine immunity to male fertility.

  2. Practice of using human excreta as fertilizer and implications for health in Nghean Province, Vietnam

    DEFF Research Database (Denmark)

    Phuc, P. D.; Konradsen, Flemming; Phuong, P. T.

    2006-01-01

    using latrine wastes as fertilizers in a community in central Vietnam. Information was collected through structured questionnaire interviews administered to 75 farming households, focus group discussions, and key informant interviews. The majority (64%) of households had a single vault latrine......, a possession that was associated with low income (chi2= 12.45; p lime likely to increase pH and pathogen die-off. About 28...

  3. Intrafollicular endocrine milieu after addition of hCG to recombinant FSH during controlled ovarian stimulation for in vitro fertilization.

    Science.gov (United States)

    Thuesen, L L; Andersen, A Nyboe; Loft, A; Smitz, J

    2014-02-01

    The role of human chorionic gonadotropin (hCG) supplementation on the intrafollicular steroid milieu has been studied. The objective of the study was to assess the impact on steroid levels in follicular fluids (FFs) after different doses of hCG supplementation to recombinant FSH for controlled ovarian stimulation. This was a prospective randomized dose-response study conducted at Copenhagen University Hospital, Rigshospitalet, Denmark. From 62 in vitro fertilization patients, 334 FFs were selected for analyses. Patients were treated using a GnRH agonist protocol with recombinant FSH 150 IU/d and randomized from stimulation day 1 to supplementation with hCG: D0, 0 IU/d; D50, 50 IU/d; D100, 100 IU/d; and D150, 150 IU/d. Intrafollicular hormone concentrations in relation to treatment groups, follicular sizes, and embryo quality were measured. In large follicles, hCG supplementation induced a nearly 3-fold increase of estradiol (nanomoles per liter) [D0: 1496; D50: 3138; D100: 4338; D150: 4009 (P D100: 72; D150: 56 (P D100 and the highest in D0. Large follicles giving rise to good-quality embryos had significantly higher estradiol and progesterone levels and estradiol to T, estradiol to androstenedione, and progesterone to estradiol ratios, compared with small follicles, leading to poor-quality embryos. Increasing doses of hCG supplementation markedly stimulated the intrafollicular concentration of both estradiol and androgens, with a shift toward a more androgenic milieu. In large follicles with oocytes giving rise to good-quality embryos, the FFs were significantly more estrogenic than in small follicles with oocytes developing into poor quality embryos.

  4. Expression of human hormone-sensitive lipase (HSL) in postmeiotic germ cells confers normal fertility to HSL-deficient mice.

    Science.gov (United States)

    Wang, Shu Pei; Chung, Shari; Soni, Krishnakant; Bourdages, Hugo; Hermo, Louis; Trasler, Jacquetta; Mitchell, Grant A

    2004-12-01

    Hormone-sensitive lipase (HSL, Lipe, E.C.3.1.1.3) is a multifunctional fatty acyl esterase that is essential for male fertility and spermatogenesis and that also plays important roles in the function of adipocytes, pancreatic beta-cells, and adrenal cortical cells. Gene-targeted HSL-deficient (HSL-/-) male mice are infertile, have a 2-fold reduction in testicular mass, a 2-fold elevation of the ratio of esterified to free cholesterol in testis, and unique morphological abnormalities in round and elongating spermatids. Postmeiotic germ cells in the testis express a specific HSL isoform. We created transgenic mice expressing a normal human testicular HSL cDNA from the mouse protamine-1 promoter, which mediates expression specifically in postmeiotic germ cells. Testicular cholesteryl esterase activity was undetectable in HSL-/- mice, but in HSL-/- males expressing the testicular transgene, activity was 2-fold greater than normal. HSL transgene mRNA became detectable in testes between 19 and 25 days of age, coinciding with the first wave of postmeiotic transcription in round spermatids. In contrast to nontransgenic HSL-/- mice, HSL-/- males expressing the testicular transgene were normal with respect to fertility, testicular mass, testicular esterified/free cholesterol ratio, and testicular histology. Their cauda epididymides contained abundant, normal-appearing spermatozoa. We conclude that human testicular HSL is functional in mouse testis and that the mechanism of infertility in HSL-deficient males is cell autonomous and resides in postmeiotic germ cells, because HSL expression in these cells is in itself sufficient to restore normal fertility.

  5. Controlled-release fertilizer prepared using a biodegradable aliphatic copolyester of poly(butylene succinate) and dimerized fatty acid.

    Science.gov (United States)

    Lubkowski, Krzysztof; Smorowska, Aleksandra; Grzmil, Barbara; Kozłowska, Agnieszka

    2015-03-18

    The preparation and characterization of a controlled-release multicomponent (NPK) fertilizer with the coating layer consisting of a biodegradable copolymer of poly(butylene succinate) and a butylene ester of dilinoleic acid (PBS/DLA) is reported. The morphology and structure of the resulting polymer-coated materials and the thickness of the covering layers were examined using X-ray diffraction and scanning electron microscopy coupled with energy dispersive X-ray analysis. The mechanical properties of these materials were determined with a strength-testing machine. Nutrient release was measured in water using spectrophotometry, potentiometry, and conductivity methods. The results of the nutrient release experiments from these polymer-coated materials were compared with the requirements for controlled-release fertilizers. A conceptual model is presented describing the mechanism of nutrient release from the materials prepared in this study. This model is based on the concentrations of mineral components inside the water-penetrated fertilizer granules, the diffusion properties of the nutrients in water, and a diffusion coefficient through the polymer layer. The experimental kinetic data on nutrient release were interpreted using the sigmoidal model equation developed in this study.

  6. [Two hundred and sixty eigth medicinal plants used to fertility control in some countries of South America (author's transl)].

    Science.gov (United States)

    Azorero, R M; Schvartzman, B

    1975-01-01

    A review is made of the various anthropological, botanical and empirical medical papers from a number of the countries of the South-American continent, whose populations use medical plants for fertility control. Also included is a field research conducted among indigenous and rural populations of Paraguay. The scientific name, family and common name 268 plants are described. With each plant, the country and type of population (indigenous or rural) using same is stated, as well as their empiric properties attributed to same and the name of the author. Comments are made upon the background related to the use of said plants at the level of the American indigenous, world folkloric and Paraguayan indigenous & folkloric medicine. Emphasis is given to the significance of these data on contraceptives, abortives, sterilization and fertilization agents of vegetal origin, due to their value for future research in the physiology and clinic of reproduction.

  7. Fertility and Fertility Control in Prerevolutionary China%新中国成立前的生育和生育控制

    Institute of Scientific and Technical Information of China (English)

    武雅士; 尹泰尔; 佟春霞; 张海洋

    2011-01-01

    本文认为李中清和王丰在《人类的四分之一:马尔萨斯神话与中国现实,1700~2000》中挑战马尔萨斯以及公认的中国解放前生育状况的观点是失败的。主要有两个原因:一是他们缺少普遍存在生育控制的证据。二是与李中清和王丰的中心论题相反,中国的总和生育率比欧洲高很多。这使得中国还是生育了超出其资源可以承受的人口。%Lee and Wang challenged to the argument of Malthus and the received fertility view of China.This paper suggests that their arguments donot hold water from two aspects.The first is they lack evidence for widespread deliberate birth control.The second is th

  8. Post-emergence weed control through abrasion with an approved organic fertilizer

    Science.gov (United States)

    Corn gluten meal (CGM) is an approved organic fertilizer and preemergence herbicide that can be manufactured in the form of grit. This grit was tested for its ability to abrade seedlings of the summer annual weedy grass, Setaria pumila, when plants were in the 1- to 5-leaf stages of growth. It was p...

  9. Studies on the effectiveness of various sulfur fertilizers under controlled conditions

    NARCIS (Netherlands)

    Dijksterhuis, G.H.; Oenema, O.

    1990-01-01

    Three factorial experiments with four replications were conducted in a greenhouse to examine the effectiveness of gypsum, elemental sulfur (ES powder) and three S containing N fertilizers, viz., ammonium sulfate (AS), urea ES, and Ureas (20% AS and 80% urea). All experiments were conducted twice in

  10. 控释氮肥在插秧水稻上的施用效果%Effects of controlled-release nitrogen fertilizer on transplanting rice

    Institute of Scientific and Technical Information of China (English)

    王翰霖

    2015-01-01

    On the basis of field experiment in 2012, to continue the experiment of different controlled release fertilizer on rice growth and yield of rice transplanting in 2013, the results show that one-time use of 60 days and 90 days two kinds of controlled release fertilizer on planting rice, rice yields were 672.3 kg and 679.7 kg, to effect a bit better of 90 days controlled release fertilizer, the difference is not obvious about two fertilizer use and conventional fertilization. Through field experiments for two consecutive years, understanding the effects of controlled release nitrogen fertilizer on rice growth and yield conditions, in order to explore the fertilizer application prospects and corresponding technical measures on rice production in Yinchuan .%在2012年田间试验的基础上,于2013年继续进行不同控释肥对插秧水稻生长与产量的影响试验.结果表明:在插秧稻上一次性施用60 d和90 d 2种控释肥时,水稻产量分别为672.3、679.7 kg/666.7 m2,以90 d控释肥效果较好,分2次施用和常规施肥差别不显著.

  11. Bacillus cereus X5 Enhanced Bio-Organic Fertilizers Effectively Control Root-Knot Nematodes (Meloidogyne sp.)

    Institute of Scientific and Technical Information of China (English)

    XIAO Tong-Jian; CHEN Fang; GAO Chao; ZHAO Qing-Yun; SHEN Qi-Rong; RAN Wei

    2013-01-01

    The efficacy of Bacillus cereus X5 as a potential biological control agent against root-knot nematodes was evaluated in vitro by examining second-stage juvenile mortality and egg hatching rate under addition of culture filtrate and in planta by application of bio-organic fertilizers enhanced with B.cereus X5,B.thuringiensis BTG,or Trichoderma harzianum SQR-T037 alone or together in greenhouse and field experiments.The biofumigation of the root-knot nematode-infested soil with organic materials (chicken manure,pig manure and rice straw) alone or in combination with B.cereus X5 was also conducted in greenhouse experiments.In laboratory,the filtrate of B.cereus X5 more effectively reduced egg hatching rates during the incubation period for 14 d and more effectively killed the second-stage juvenile during the incubation period of 24 h than that of B.thuringiensis BTG.The highest dry shoot weights for greenhouse tomatoes and field muskmelons were found in both the treatment consisting of the bio-organic fertilizer enhanced with the three biocontrol agents and the treatment consisting of the bio-organic fertilizer enhanced only with B.cereus X5.The two bio-organic fertilizers achieved better nematicidal effects than those enhanced only with B.thuringiensis BTG or T.harzianum SQR-T037.B.cereus X5 also enhanced effect of biofumigation,which resulted in increased plant biomass and reduced nematode counts in the roots and rhizosphere soil.Therefore,these results suggested that biological control of root-knot nematodes both in greenhouses and fields could be effectively achieved by using B.cereus X5 and agricultural wastes.

  12. Development on significance of slow/controlled release fertilizer%积极发展缓控释肥的重大意义

    Institute of Scientific and Technical Information of China (English)

    曲均峰; 傅送保; 操斌

    2011-01-01

    Based on the status of low fertilizer utilization rate and return rate in china, the necessity of slow / controlled release fertilizer development, development background and great significance are analyzed, and some suggestions on the slow/controlled release fertilizer future development are proposed.%根据我国农业用肥利用率低、回报率低等现状,分析缓控释肥开发的必要性、发展背詈及重大意义,并对缓控释肥未来发展提出了建议。

  13. Nitrogen recovery from source-separated human urine using clinoptilolite and preliminary results of its use as fertilizer.

    Science.gov (United States)

    Beler-Baykal, B; Allar, A D; Bayram, S

    2011-01-01

    The use of source separated human urine as fertilizer is one of the major suggestions of the new sanitation concept ECOSAN. Urine is rich in nitrogen, phosphorus and potassium which act as plant nutrients, however its salinity is high for agricultural and landscape purposes. Moreover, characteristics change significantly throughout storage where salinity increases to higher values as the predominant form of nitrogen shifts from urea to ammonium. Transferring nitrogen in human urine onto the natural zeolite clinoptilolite and using the subsequently recovered ammonium from the exhausted clinoptilolite for agricultural/landscape purposes is suggested as an indirect route of using urine in this work. Results reporting the outcome of the proposed process together with characterization of fresh and stored urine, and preliminary work on the application of the product on the landscape plant Ficus elastica are presented. Up to 97% of the ammonium in stored urine could be transferred onto clinoptilolite through ion exchange and about 88% could be recovered subsequently from exhausted clinoptilolite, giving an overall recovery of 86%. Another important merit of the suggested process was the successful elimination of salinity. Preliminary experiments with Ficus elastica had shown that the product, i.e. clinoptilolite exhausted with ammonium, was compatible with the synthetic fertilizer tested.

  14. In vitro fertilization (IVF) in mammals: epigenetic and developmental alterations. Scientific and bioethical implications for IVF in humans.

    Science.gov (United States)

    Ventura-Juncá, Patricio; Irarrázaval, Isabel; Rolle, Augusto J; Gutiérrez, Juan I; Moreno, Ricardo D; Santos, Manuel J

    2015-12-18

    The advent of in vitro fertilization (IVF) in animals and humans implies an extraordinary change in the environment where the beginning of a new organism takes place. In mammals fertilization occurs in the maternal oviduct, where there are unique conditions for guaranteeing the encounter of the gametes and the first stages of development of the embryo and thus its future. During this period a major epigenetic reprogramming takes place that is crucial for the normal fate of the embryo. This epigenetic reprogramming is very vulnerable to changes in environmental conditions such as the ones implied in IVF, including in vitro culture, nutrition, light, temperature, oxygen tension, embryo-maternal signaling, and the general absence of protection against foreign elements that could affect the stability of this process. The objective of this review is to update the impact of the various conditions inherent in the use of IVF on the epigenetic profile and outcomes of mammalian embryos, including superovulation, IVF technique, embryo culture and manipulation and absence of embryo-maternal signaling. It also covers the possible transgenerational inheritance of the epigenetic alterations associated with assisted reproductive technologies (ART), including its phenotypic consequences as is in the case of the large offspring syndrome (LOS). Finally, the important scientific and bioethical implications of the results found in animals are discussed in terms of the ART in humans.

  15. Complex nanominerals and ultrafine particles assemblages in phosphogypsum of the fertilizer industry and implications on human exposure

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Luis F.O., E-mail: felipeqma@yahoo.com.br [Catarinense Institute of Environmental Research and Human Development-IPADHC, Capivari de Baixo, Santa Catarina (Brazil); Hower, James C. [University of Kentucky Center for Applied Energy Research, Lexington, KY, 40511 (United States); Izquierdo, Maria; Querol, Xavier [Institute of Environmental Assessment and Water Research (IDAEA-CSIC) C/Lluis Sole y Sabaris s/n, 08028 Barcelona (Spain)

    2010-10-01

    Phosphogypsum (CaSO{sub 4}.2H{sub 2}O), a by-product of phosphate-rock processing, contains high amounts of impurities such P{sub 2}O{sub 5}, F, radioactive elements, organic substances, secondary nanominerals, and ultrafine particles (UFP) enriched in metals and metalloids. In this study, we examine phosphogypsum (PG) collected from abandoned fertilizer industry facility in south Brazil (Santa Catarina state). The fragile nature of nanominerals and UFP assemblages from fertilizer industry systems required novel techniques and experimental approaches. The investigation of the geochemistry of complex nanominerals and UFP assemblages was a prerequisite to accurately assess the environmental and human health risks of contaminants and cost-effective chemical and biogeological remediation strategies. Particular emphasis was placed on the study and characterization of the complex mixed nanominerals and UFP containing potentially toxic elements. Nanometer-sized phases in PG were characterized using energy-dispersive X-ray spectrometer (EDS), field-emission scanning electron microscope (FE-SEM), and high-resolution transmission electron microscopy (HR-TEM) images. The chemical composition and possible correlations with morphology of nanominerals and UFP, as well as aspects of nanominerals and UFP, are discussed in the context of human health exposure, as well as in relation to management of the nanominerals and UFP in PG environments.

  16. Complex nanominerals and ultrafine particles assemblages in phosphogypsum of the fertilizer industry and implications on human exposure.

    Science.gov (United States)

    Silva, Luis F O; Hower, James C; Izquierdo, Maria; Querol, Xavier

    2010-10-01

    Phosphogypsum (CaSO(4).2H(2)O), a by-product of phosphate-rock processing, contains high amounts of impurities such P(2)O(5), F, radioactive elements, organic substances, secondary nanominerals, and ultrafine particles (UFP) enriched in metals and metalloids. In this study, we examine phosphogypsum (PG) collected from abandoned fertilizer industry facility in south Brazil (Santa Catarina state). The fragile nature of nanominerals and UFP assemblages from fertilizer industry systems required novel techniques and experimental approaches. The investigation of the geochemistry of complex nanominerals and UFP assemblages was a prerequisite to accurately assess the environmental and human health risks of contaminants and cost-effective chemical and biogeological remediation strategies. Particular emphasis was placed on the study and characterization of the complex mixed nanominerals and UFP containing potentially toxic elements. Nanometer-sized phases in PG were characterized using energy-dispersive X-ray spectrometer (EDS), field-emission scanning electron microscope (FE-SEM), and high-resolution transmission electron microscopy (HR-TEM) images. The chemical composition and possible correlations with morphology of nanominerals and UFP, as well as aspects of nanominerals and UFP, are discussed in the context of human health exposure, as well as in relation to management of the nanominerals and UFP in PG environments.

  17. Thermal post-treatment alters nutrient release from a controlled-release fertilizer coated with a waterborne polymer

    OpenAIRE

    Zijun Zhou; Changwen Du; Ting Li; Yazhen Shen; Jianmin Zhou

    2015-01-01

    Controlled-release fertilizers (CRF) use a controlled-release technology to enhance the nutrient use efficiency of crops. Many factors affect the release of nutrients from the waterborne polymer-coated CRF, but the effects of thermal post-treatments remain unclear. In this study, a waterborne polyacrylate-coated CRF was post-treated at different temperatures (30 °C, 60 °C, and 80 °C) and durations (2, 4, 8, 12, and 24 h) after being developed in the Wurster fluidized bed. To characterize the ...

  18. Thermal post-treatment alters nutrient release from a controlled-release fertilizer coated with a waterborne polymer

    OpenAIRE

    Zijun Zhou; Changwen Du; Ting Li; Yazhen Shen; Jianmin Zhou

    2015-01-01

    Controlled-release fertilizers (CRF) use a controlled-release technology to enhance the nutrient use efficiency of crops. Many factors affect the release of nutrients from the waterborne polymer-coated CRF, but the effects of thermal post-treatments remain unclear. In this study, a waterborne polyacrylate-coated CRF was post-treated at different temperatures (30 °C, 60 °C, and 80 °C) and durations (2, 4, 8, 12, and 24 h) after being developed in the Wurster fluidized bed. To characterize the ...

  19. Non-Exhaustible Solar-Power Based Insecticide or Bio-fertilizer Sprayer for Use in Agronomics (With Bluetooth Enabled Control

    Directory of Open Access Journals (Sweden)

    B Dodda Basavana Goud

    2017-04-01

    Full Text Available Agronomics is a profession of many related sequential and sometimes concurrent tedious processes and methodologies. The Primary process among many is the spraying of insecticides, pesticides, liquefied fertilizers in the agricultural farmlands. The typical rice growing land requires extensive spraying during its growing stages. The manual methods to spray the insecticides or fertilizers are: a person fixing a sprayer to a container and manually actuating a lever to generate pressure and pumping the contents through a tube or a mobile vehicle carrying an inbuilt compressor and sprayer unit which has to be manually driven by a human operator. These conventional methods are more fuel consuming and are also susceptible to human errors causing more uneven spraying and causes large wastage of the costly insecticides. . Another big drawback in human operated systems is that the operator is more exposed to the harmful ingredients of the toxic insecticides during spraying. Long term exposure in the entire season will extremely harm the operator and as well as the surrounding people and animal’s health as bullocks are the laboring animals in the farmlands at larger areas of farmlands in south-Asia even now. This is a small effort which can be observed as an alternate to these manual methods. The proposed Automatic sprayer system is a three wheeled vehicle which sprays insecticide in any given farmland especially the rice growing south Asia zone where human involvement is to the large extent. The vehicle is powered by using solar powered battery which brings down the running cost. The control of the vehicle is achieved using an inbuilt microcontroller unit which is programmed so as to respond to the wireless device.

  20. Effects of Controlled-Release Fertilizers and Their Application Methods on Germination and Seedling Growth of Dent and Sweet Corns

    Institute of Scientific and Technical Information of China (English)

    TIAN Xiao-hong; SAIGUSA Masahiko; KIKAWA Naoto

    2005-01-01

    Effects of controlled-release fertilizers (CRFs) (C-AS, polyolefin coated ammonium sulfate, 50-day-type; Dd-LP, polyolefin coated urea with dicyandiamide, 40-day-type; C-ANP, polyolefin coated ammonium nitrate phosphate, 40-day-type; and C-DAP, polyolefin coated diammonium acid phosphate, 40-day-type), ammonium sulphate and no fertilizer control, and their application methods (spot, band, surface and mixed) on germination and seedling development of sweet corn (Zea mays L.var. saccharata Sturt.) and dent corn (Zea mays L.var. indentata Sturt.) were investigated in a greenhouse. Under co-situs application (band and spot) of CRFs, there were no obvious differences in the germination speed and rate for both dent corn and sweet corn relative to control. Mortality rates of sweet corn seedlings under co-situs application were high in experiment 1, but were very low in experiment 2, because the environmental conditions were different in the two experiments. That is, under lower temperature and weaker sunlight, young seedlings easily die due to high soil nutrient concentration and slow growth speed of corn. Shoot weight of both dent and sweet corn did not greatly decrease in experiment 1. In experiment 2, there were no significant differences in shoot and root weight of both corns between cositus and surface or mixed application methods. However, with spot and band application of ammonium sulfate, shoot and root weight were significantly reduced. Soil EC and pH were considerably affected by co-situs application, especially at the fertilizer application site. For both dent and sweet corn, EC in the 0-3 cm soil was significantly higher under co-situs application and surface application than that under mixed application, whereas in the 3-6 cm soil depth the situation was reversed. Compared with control, mixed application of CRFs decreased soil pH slightly (0-3 cm depth) or greatly (3-6 cm depth).

  1. Mycorrhizal association as a primary control of the CO₂ fertilization effect.

    Science.gov (United States)

    Terrer, César; Vicca, Sara; Hungate, Bruce A; Phillips, Richard P; Prentice, I Colin

    2016-07-01

    Plants buffer increasing atmospheric carbon dioxide (CO2) concentrations through enhanced growth, but the question whether nitrogen availability constrains the magnitude of this ecosystem service remains unresolved. Synthesizing experiments from around the world, we show that CO2 fertilization is best explained by a simple interaction between nitrogen availability and mycorrhizal association. Plant species that associate with ectomycorrhizal fungi show a strong biomass increase (30 ± 3%, P nitrogen availability, whereas low nitrogen availability limits CO2 fertilization (0 ± 5%, P = 0.946) in plants that associate with arbuscular mycorrhizal fungi. The incorporation of mycorrhizae in global carbon cycle models is feasible, and crucial if we are to accurately project ecosystem responses and feedbacks to climate change.

  2. 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.

  3. Evaluation of human embryo development in in vitro fertilization- and intracytoplasmic sperm injection-fertilized oocytes: A time-lapse study.

    Science.gov (United States)

    Kim, Hyung Jun; Yoon, Hye Jin; Jang, Jung Mi; Lee, Won Don; Yoon, San Hyun; Lim, Jin Ho

    2017-06-01

    We investigated whether the insemination method (in vitro fertilization [IVF] or intracytoplasmic sperm injection [ICSI]) affected morphokinetic events and abnormal cleavage events in embryonic development. A total of 1,830 normal fertilized embryos were obtained from 272 IVF and ICSI cycles that underwent ovum retrieval culture using a time-lapse system (Embryoscope) from June 2013 to March 2015. All embryos were investigated by a detailed time-lapse analysis that measured the developmental events in the hours after IVF or ICSI insemination. No significant differences were observed between the two groups regarding clinical outcomes (p>0.05). ICSI-derived embryos showed significantly faster morphokinetics than those derived from conventional IVF, from the time to pronuclear fading to the time to 6 cells (p0.05). There were no differences in abnormal cleavage events between the two groups (p>0.05); they showed the same rates of direct cleavage from 1 to 3 cells, 2 multinucleated cells, 2 uneven cells, and reverse cleavage. The morphokinetics of embryo development was found to vary between IVF- and ICSI-fertilized oocytes, at least until the 6-cell stage. However, these differences did not affect the clinical outcomes of the embryo. Additionally, no significant differences in abnormal cleavage events were found according to the fertilization method.

  4. Control of fertilization-independent endosperm development by the MEDEA polycomb gene in Arabidopsis.

    Science.gov (United States)

    Kiyosue, T; Ohad, N; Yadegari, R; Hannon, M; Dinneny, J; Wells, D; Katz, A; Margossian, L; Harada, J J; Goldberg, R B; Fischer, R L

    1999-03-30

    Higher plant reproduction is unique because two cells are fertilized in the haploid female gametophyte. Egg and sperm nuclei fuse to form the embryo. A second sperm nucleus fuses with the central cell nucleus that replicates to generate the endosperm, a tissue that supports embryo development. To understand mechanisms that initiate reproduction, we isolated a mutation in Arabidopsis, f644, that allows for replication of the central cell and subsequent endosperm development without fertilization. When mutant f644 egg and central cells are fertilized by wild-type sperm, embryo development is inhibited, and endosperm is overproduced. By using a map-based strategy, we cloned and sequenced the F644 gene and showed that it encodes a SET-domain polycomb protein. Subsequently, we found that F644 is identical to MEDEA (MEA), a gene whose maternal-derived allele is required for embryogenesis [Grossniklaus, U., Vielle-Calzada, J.-P., Hoeppner, M. A. & Gagliano, W. B. (1998) Science 280, 446-450]. Together, these results reveal functions for plant polycomb proteins in the suppression of central cell proliferation and endosperm development. We discuss models to explain how polycomb proteins function to suppress endosperm and promote embryo development.

  5. Pro-oxidative and anti-oxidative imbalance in human semen and its relation with male fertility

    Institute of Scientific and Technical Information of China (English)

    NicolasGarrido; MarcosMeseguer; CarlosSimon; AntonioPellicer; JoséRemohi

    2004-01-01

    Oxidative stress is a common condition suffered by biological systems in aerobic conditions.Human semen also has its own molecular guard against the free radicals created by normal respiratory process or from immune reactions.The equilibrium of the creation and scavenging of free radicals is mandatory in the spermatozoa to fertilize and initiate a full-term pregnancy.The paper is a systematic review of publications that evaluate oxidative stress in semen.The Cochrane Library,Medline (1966-2003),Embase (1988-2003),SciSearch (1981-2003) and the conference papers were searched,When sperm samples from fertile and infertile males were analyzed,some of the mechanisms that determine the oxidative stress level were found to be impaired while others were unaltered.In conclusion,the literature as a whole provides contradictory findings and it is necessary to carry out more work to identify all the enzymatic and non-enzymatic systems involved in oxidative stress in the ejaculate,in order to develop new diagnostic systems and therapeutic strategies for combating detrimental free radical imbalance in the semen.(Asian J Androl 2004 Mar;6:59-65)

  6. 控释掺混专用肥对水稻生长的影响%Effects of Controlled-release Compound Fertilizer on Growth of Paddy Rice

    Institute of Scientific and Technical Information of China (English)

    郑磊; 陈宝成; 范玲超; 王怀利; 蒋曦龙; 齐英杰

    2013-01-01

    In order to provide scientific evidence for the production and safety application of the special controlled-release fertilizer for paddy rice, field experiment was conducted to study the effects of controlled-release fertilizer on paddy rice yield, fertilizer utilization and economic benefit. The results indicated that: compared with common fertilization, there was no significant difference on the height and lamina chlorophyll content of paddy rice under controlled-release compound fertilizations with various nutrient proportions and different fertilization. Based on the same application of fertilizers, the level of soil nutrient was higher under controlled-release compound fertilizer treatments than under common fertilizations, controlled-release compound fertilization increased the content of N, P and K in paddy rice 5.0%-20.3%, 2.7%-40.8%,-8.2%-39.9%, respectively. The yield of paddy rice increased up to 6.90%-15.3% under controlled-release compound fertilizer treatments. The utilization rate of nitrogen, phosphorus, potassium fertilizers was 6.07%-29.91%, 41.86%-85.57%, 38.57%-95.43%, respectively. The income of paddy rice under controlled-release compound fertilizer enhanced 537-1296 yuan/hm2 in comparison with common fertilization. Controlled-release compound fertilizer could effectively simplified the cultivation techniques of paddy rice, and special controlled release fertilizer for paddy rice should be developed and promoted actively.%为了保证控释肥在水稻生产中的安全施用和水稻专用控释肥的生产改进提供科学依据,通过采用田间小区试验的方法,研究了不同控释肥处理对水稻产量、肥料利用率和经济效益的影响。结果表明,与普通肥相比,等量控释肥、减量控释肥、减氮控释肥、种子保姆肥不能显著提高水稻株高和叶绿素含量;施肥量相近下,控释掺混肥处理土壤养分含量较高;水稻吸收氮磷钾量分别提高5.0%~20.3%、2

  7. Application Effect of Controlled-Release BB Fertilizers on Wheat%控失BB肥在小麦上的应用效果∗

    Institute of Scientific and Technical Information of China (English)

    孙克刚; 李玉顺; 和爱玲; 张运红; 顾朝晖; 岳艳军; 冯梦喜

    2016-01-01

    为了验证控失BB肥的优越性并发现其在施用过程中存在的问题,为进一步改进控失尿素产品提出建议,对控失BB肥在小麦上的应用效果进行了大田试验和示范处理。试验结果表明,控失BB肥能有效提高氮肥利用率,但氮肥利用率随氮肥使用量的增加而下降。示范结果表明,控失BB肥比普通BB肥处理小麦增产372.0 kg/hm2,增产率4.7%。%In order to verify the superiority of controlled-release BB fertilizer and to find problems existing in application, and to make suggestions for further improving controlled-release urea products, the field experiment and treatment demonstration of controlled-release BB fertilizer application effect on wheat are carried out. Experimental results show that controlled-release BB fertilizer can improve utilization ratio of nitrogen fertilizer effectively, but nitrogen fertilizer utilization ratio decreases with the increase in amount of nitrogen fertilizer used. Treatment demonstration results show that with controlled-release BB fertilizer the wheat yield increases by 372. 0 kg/hm2 than that of common BB fertilizer, the rate of growth is 4. 7%.

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

    Directory of Open Access Journals (Sweden)

    Hidenobu Okuda

    Full Text Available BACKGROUND: 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. METHODS AND FINDING: 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. CONCLUSION: 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.

  9. Fertility defects in mice expressing the L68Q variant of human cystatin C: a role for amyloid in male infertility.

    Science.gov (United States)

    Whelly, Sandra; Serobian, Gaiane; Borchardt, Clinton; Powell, Jonathan; Johnson, Seethal; Hakansson, Katarina; Lindstrom, Veronica; Abrahamson, Magnus; Grubb, Anders; Cornwall, Gail A

    2014-03-14

    Hereditary cystatin C amyloid angiopathy is an autosomal dominant disorder in which a variant form of cystatin C (L68Q) readily forms amyloid deposits in cerebral arteries in affected individuals resulting in early death. L68Q protein deposits in human cystatin C amyloid angiopathy patients have also been found in tissues outside of the brain including the testis, suggesting possible effects on fertility. Heterozygous transgenic mice (L68Q) that express the human L68Q variant of cystatin C under the control of the mouse cystatin C promoter were unable to generate offspring, suggesting the presence of L68Q cystatin C amyloid affected sperm function. In vitro studies showed that epididymal spermatozoa from L68Q mice were unable to fertilize oocytes and exhibited poor sperm motility. Furthermore, spermatozoa from L68Q mice exhibited reduced cell viability compared with wild type (WT) spermatozoa and often were detected in large agglutinated clumps. Examination of the epididymal fluid and spermatozoa from L68Q mice showed increased levels and distinct forms of cystatin C amyloid that were not present in WT mice. The addition of epididymal fluid from L68Q mice to WT spermatozoa resulted in a recapitulation of the L68Q phenotype in that WT spermatozoa showed reduced cell viability and motility compared with WT spermatozoa incubated in epididymal fluid from WT mice. L68Q epididymal fluid that was depleted of cystatin C amyloids, however, did not impair the motility of WT spermatozoa. Taken together these studies suggest that amyloids in the epididymal fluid can be cytotoxic to the maturing spermatozoa resulting in male infertility.

  10. Surfactant modified coir pith, an agricultural solid waste as adsorbent for phosphate removal and fertilizer carrier to control phosphate release.

    Science.gov (United States)

    Namasivayam, C; Kumar, M V Suresh

    2005-10-01

    The surface of coir pith, an agricultural solid waste was modified using a cationic surfactant, hexadecyltrimethylammonium bromide (HDTMA) and the modified coir pith was investigated to assess the capacity for the removal of phosphate from aqueous solution. Optimum pH for maximum phosphate adsorption was found to be 4.0. Langmuir and Freundlich isotherms were used to model the adsorption equilibrium data. Kinetic studies showed that the adsorption obeyed second order kinetics. Thermodynamic parameters were evaluated and the overall adsorption process was spontaneous and endothermic. Effect of coexisting anions has also been studied. The feasibility of using spent adsorbent as fertilizer carrier to control phosphate release was also investigated.

  11. 缓/控释化肥合成研究的新进展%New development of preparation of slow/controlled release fertilizer

    Institute of Scientific and Technical Information of China (English)

    陈建超; 刘华; 刘俊杰; 刘亚青

    2011-01-01

    drawbacks caused by the traditional fertilizer. In this paper, the pollution damage to environment and food safety caused by the traditional fertilizer is briefly pointed out. In contrast, several sorts of slow/controlled release fertilizers such as chemically modified, biochemically modified, physically encapsulated and biochemically & physically encapsulated modified fertilizer,classified according to the manufacture process and slow/controlled release mechanism, are introduced in detail. Furthermore, the prospect of slow/controlled release fertilizer is also proposed.slow/controlled release fertilizer; synthesis; development%缓/控释化肥的合成研究是目前肥料领域发展的热点之一,缓/控释化肥可有效弥补传统肥料带来的诸多缺点.简述了传统肥料对环境和食品安全的危害,根据缓/控释化肥的制造工艺和释放原理,重点介绍了化学型、生物化学型、物理包膜型和生物化学与物理包膜结合型缓/控释化肥合成方法的现状,并对缓/控释化肥的发展进行了展望.

  12. Altered cleavage patterns in human tripronuclear embryos and their association to fertilization method

    DEFF Research Database (Denmark)

    Joergensen, Mette Warming; Agerholm, Inge; Hindkjaer, Johnny

    2014-01-01

    PURPOSE: To analyze the cleavage patterns in dipronuclear (2PN) and tripronuclear (3PN) embryos in relation to fertilization method. METHOD: Time-lapse analysis. RESULTS: Compared to 2PN, more 3PN IVF embryos displayed early cleavage into 3 cells (p cell...... stage (p cell divisions within the cleavage cycles differed between the two groups. In contrast......, the completion of the 1st, 2nd, and 3rd cleavage cycle was delayed, but with a similar division pattern for 3PN ICSI compared with the 2PN ICSI embryos. 3PN, more often than 2PN ICSI embryos, displayed early cleavage into 3 cells (p = 0.03) and arrested development from the compaction stage and onwards (p = 0...

  13. Fertility Awareness

    Science.gov (United States)

    ... I Help Someone Who's Being Bullied? Volunteering Fertility Awareness KidsHealth > For Teens > Fertility Awareness Print A A A What's in this article? ... español Monitoreo de fertilidad What Is It? Fertility awareness is a way to prevent pregnancy by not ...

  14. 缓控释肥在蜜柚上的施用效果研究%Effects of Slow-Controlled Release Fertilizer on Honeyed Shaddock

    Institute of Scientific and Technical Information of China (English)

    吴凌云; 李志忠; 丁文

    2011-01-01

    蜜柚施用缓控释肥的田间试验结果表明,缓控释肥处理比配方施肥、习惯施肥处理分别增产4.76%、12.35%;缓控释肥处理与习惯施肥处理相比,柚子可溶性总糖、可溶性固形物和维生素C含量分别提高0.6%、0.9%和1.9 mg/100 g;缓控释肥、配方施肥处理比习惯施肥处理每667 m2产值分别增加588.0元、345.0元,纯收益分别增加544.0元、461.9元。%A field experiment was conducted with application of slow controlled release fertilizer in honeyed shaddock.The results showed that slow-controlled releasing fertilizer could increase the yield of honey shaddock by 4.76% and 12.35% than formulated and regular fertilization,respectively.Compared with regular fertilization,slow-controlled releasing fertilizer increased the soluble sugar content by 0.6%,soluble solids by 0.9%,and vitamin C content by 1.9 mg/100 g in honeyed shaddock.Meanwhile,compared with regular fertilization,slow controlled release fertilizer and formulated fertilization increased the yield of honeyed shaddock per 667 m2(0.067 hm2) by 588.0 and 345.0 Yuan,and increased the net economical benefit by 544.0 and 461.9 Yuan per 667 m2(0.067 hm2).

  15. Wastewater reuse in irrigation: a microbiological perspective on implications in soil fertility and human and environmental health.

    Science.gov (United States)

    Becerra-Castro, Cristina; Lopes, Ana Rita; Vaz-Moreira, Ivone; Silva, Elisabete F; Manaia, Célia M; Nunes, Olga C

    2015-02-01

    The reuse of treated wastewater, in particular for irrigation, is an increasingly common practice, encouraged by governments and official entities worldwide. Irrigation with wastewater may have implications at two different levels: alter the physicochemical and microbiological properties of the soil and/or introduce and contribute to the accumulation of chemical and biological contaminants in soil. The first may affect soil productivity and fertility; the second may pose serious risks to the human and environmental health. The sustainable wastewater reuse in agriculture should prevent both types of effects, requiring a holistic and integrated risk assessment. In this article we critically review possible effects of irrigation with treated wastewater, with special emphasis on soil microbiota. The maintenance of a rich and diversified autochthonous soil microbiota and the use of treated wastewater with minimal levels of potential soil contaminants are proposed as sine qua non conditions to achieve a sustainable wastewater reuse for irrigation.

  16. The role of Angiotensin-converting enzyme in blood pressure control, renal function, and male fertility.

    Science.gov (United States)

    Esther, C R; Marino, E M; Bernstein, K E

    1997-07-01

    Angiotensin-converting enzyme (ACE) is a zinc peptidase that plays a major role in the renin-angiotensin system. In mammals, the enzyme is present as two isozymes: a somatic form involved in blood-pressure regulation and a testis form of unknown function. Mice lacking ACE have been created and shown to have low systolic blood pressures and defects in renal development and function. These mice also have reduced male fertility, implicating the testis isozyme in reproductive function. (Trends Endocrinol Metab 1997;8:181-186). (c) 1997, Elsevier Science Inc.

  17. Human Operator Control Strategy Model.

    Science.gov (United States)

    1980-04-01

    fashion. HOPE reflects the two-store theory of memory current in the psycho- logical literature ( Atkinson & Shiffrin , 1968; Broadbent, 1971). Two...uncertainty. In P.M.A. Rabbit & S. Dornic (Eds.), Attention and performance V. New York: Academic Press, 1975. Atkinson , R. C., & Shiffrin , R. M. Human...48 2. The Perception Process ... ............... 50 3. The Command Memory and Command Selection Process

  18. Residual effects of fertilization history increase nitrous oxide emissions from zero-N controls:Implications for estimating fertilizer-induced emission factors

    Science.gov (United States)

    Agricultural N fertilization is the dominant driver of increasing atmospheric nitrous oxide (N2O) concentrations over the past half century, yet there is considerable uncertainty in estimates of N2O emissions from agriculture. Such estimates are typically based on the amount of N applied and a ferti...

  19. Combined GnRH-agonist and human chorionic gonadotropin trigger improves ICSI cycle outcomes in patients with history of poor fertilization.

    Science.gov (United States)

    Elias, Rony T; Pereira, Nigel; Artusa, Lisa; Kelly, Amelia G; Pasternak, Monica; Lekovich, Jovana P; Palermo, Gianpiero D; Rosenwaks, Zev

    2017-06-01

    The purpose of this study was to investigate the utility of a combined GnRH-agonist (GnRH-a) and human chorionic gonadotropin (hCG) trigger in improving ICSI cycle outcomes in patients with poor fertilization history after standard hCG trigger in prior ICSI cycles. Retrospective cohort study. Patients with a fertilization rate of trigger were compared to those who underwent another ICSI cycle with a combined GnRH-a and hCG trigger. Oocyte maturity, fertilization, clinical pregnancy, and live birth rates were compared. A multiple linear regression model was used to explore the association between combined GnRH-a and hCG trigger (vs hCG trigger alone) and fertilization rate. A total of 427 patients with mean age of 37.3 ± 1.94 years and mean baseline fertilization rate of 17.9 ± 2.03% were included, of which 318 (74.5%) and 109 (25.5%) patients underwent a subsequent ICSI cycle with hCG and combined GnRH-a and hCG trigger, respectively. The baseline parameters of the male and female partner were similar. The mean fertilization rate in the combined trigger group was 16.4% (95% CI: 7.58-25.2%) higher than the hCG trigger group, even after adjustment for confounders. Patients in the combined trigger group had higher oocyte maturity (82.1 vs 69.8%), higher clinical pregnancy (27.5 vs 5.67%), and higher live birth rates (20.2 vs 3.46%) compared to the hCG trigger group. Combined GnRH-a and hCG trigger in ICSI cycles increase oocyte maturity, fertilization, clinical pregnancy, and live birth rates in patients with a history of poor fertilization after standard hCG trigger alone.

  20. [Effects of coffee and caffeine on fertility, reproduction, lactation, and development. Review of human and animal data].

    Science.gov (United States)

    Nehlig, A; Debry, G

    1994-01-01

    In the present review, we have examined the effects of coffee ingestion on fertility, reproduction, lactation and development. The potential effects of coffee consumption on fertility, spontaneous abortion and prematurity are not clearly established but appear to be quite limited. In rodents, caffeine can induce malformations but this effect appears in general at doses never encountered in humans. Indeed, as soon as the quantity of caffeine is divided over the day, as is the case for human consumption, the teratogenic effect of caffeine disappears in rodents. Coffee ingested during gestation induces a dose-dependent decrease in birth weight, but usually only when ingested amounts are high (i.e. more than 7 cups/day), whereas coffee has no effect at moderate doses. Caffeine consumption during gestation affects hematologic parameters of the new-born infant or rat. In animals, caffeine induces long-term consequences on sleep, locomotion, learning abilities, emotivity and anxiety, whereas, in children, the effects of early exposure to coffee and caffeine on behavior are not clearly established. The quantities of caffeine found in maternal milk vary with authors, but it appears clearly that caffeine does not change maternal milk composition and has a tendency to stimule milk production. In conclusion to this review, it appears that maternal coffee or caffeine consumption during gestation and/or lactation does not seem to have measurable consequences on the fetus of the newborn, as long as ingested quantities remain moderate. Therefore, pregnant mothers should be advised to limit their coffee and caffeine intake to 300 mg caffeine/day (i.e. 2-3 cups of coffee or 2.5-3 l of coke) especially because of the increase of caffeine half-life during the third trimester of pregnancy and in the neonate.

  1. 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, Séverine

    2015-01-01

    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-t

  2. Deleterious effects of obesity upon the hormonal and molecular mechanisms controlling spermatogenesis and male fertility.

    Science.gov (United States)

    Davidson, Lien M; Millar, Kate; Jones, Celine; Fatum, Muhammad; Coward, Kevin

    2015-09-01

    Worldwide obesity rates have nearly doubled since 1980 and currently over 10% of the population is obese. In 2008, over 1.4 billion adults aged 20 years and older had a body mass index or BMI above a healthy weight and of these, over 200 million men and nearly 300 million women were obese. While obesity can have many ramifications upon adult life, one growing area of concern is that of reproductive capacity. Obesity affects male infertility by influencing the hypothalamic-pituitary-gonadal axis, thus causing detrimental effects upon spermatogenesis and subsequent fertility. In particular, evidence indicates that excess adipose tissue can alter the relative ratio of testosterone and oestrogen. Additional effects involve the homeostatic disruption of insulin, sex-hormone-binding-globulin, leptin and inhibin B, leading to diminished testosterone production and impairment to spermatogenesis. Aberrant spermatogenesis arising from obesity is associated with downstream changes in key semen parameters, defective sperm capacitation and binding, and deleterious effects on sperm chromatin structure. More recent investigations into trans-generational epigenetic inheritance further suggest that molecular changes in sperm that arise from obesity-related impaired spermatogenesis, such as modified sperm RNA levels, DNA methylation, protamination and histone acetylation, can impact upon the development of offspring. Here, we summarise our current understanding of how obesity exerts influence over spermatogenesis and subsequent fertility status, and make recommendations for future investigative research.

  3. Not all sperm are equal: functional mitochondria characterize a subpopulation of human sperm with better fertilization potential.

    Directory of Open Access Journals (Sweden)

    Ana Paula Sousa

    Full Text Available Human sperm samples are very heterogeneous and include a low amount of truly functional gametes. Distinct strategies have been developed to characterize and isolate this specific subpopulation. In this study we have used fluorescence microscopy and fluorescence-activated cell sorting to determine if mitochondrial function, as assessed using mitochondrial-sensitive probes, could be employed as a criterion to obtain more functional sperm from a given ejaculate. We first determined that mitochondrial activity correlated with the quality of distinct human samples, from healthy donors to patients with decreased semen quality. Furthermore, using fluorescence-activated cell sorting to separate sperm with active and inactive mitochondria we found that this was also true within samples. Indeed, sperm with active mitochondria defined a more functional subpopulation, which contained more capacitated and acrosome intact cells, sperm with lower chromatin damage, and, crucially, sperm more able to decondense and participate in early development using both chemical induction and injection into mature bovine oocytes. Furthermore, cell sorting using mitochondrial activity produced a more functional sperm subpopulation than classic swim-up, both in terms of improvement in a variety of functional sperm parameters and in statistical significance. In conclusion, whatever the true biological role of sperm mitochondria in fertilization, mitochondrial activity is a clear hallmark of human sperm functionality.

  4. Not all sperm are equal: functional mitochondria characterize a subpopulation of human sperm with better fertilization potential.

    Science.gov (United States)

    Sousa, Ana Paula; Amaral, Alexandra; Baptista, Marta; Tavares, Renata; Caballero Campo, Pedro; Caballero Peregrín, Pedro; Freitas, Albertina; Paiva, Artur; Almeida-Santos, Teresa; Ramalho-Santos, João

    2011-03-23

    Human sperm samples are very heterogeneous and include a low amount of truly functional gametes. Distinct strategies have been developed to characterize and isolate this specific subpopulation. In this study we have used fluorescence microscopy and fluorescence-activated cell sorting to determine if mitochondrial function, as assessed using mitochondrial-sensitive probes, could be employed as a criterion to obtain more functional sperm from a given ejaculate. We first determined that mitochondrial activity correlated with the quality of distinct human samples, from healthy donors to patients with decreased semen quality. Furthermore, using fluorescence-activated cell sorting to separate sperm with active and inactive mitochondria we found that this was also true within samples. Indeed, sperm with active mitochondria defined a more functional subpopulation, which contained more capacitated and acrosome intact cells, sperm with lower chromatin damage, and, crucially, sperm more able to decondense and participate in early development using both chemical induction and injection into mature bovine oocytes. Furthermore, cell sorting using mitochondrial activity produced a more functional sperm subpopulation than classic swim-up, both in terms of improvement in a variety of functional sperm parameters and in statistical significance. In conclusion, whatever the true biological role of sperm mitochondria in fertilization, mitochondrial activity is a clear hallmark of human sperm functionality.

  5. The nuclear mitotic apparatus (NuMA) protein: localization and dynamics in human oocytes, fertilization and early embryos.

    Science.gov (United States)

    Alvarez Sedó, Cristian; Schatten, Heide; Combelles, Catherine M; Rawe, Vanesa Y

    2011-06-01

    The oocyte's meiotic spindle is a dynamic structure that relies on microtubule organization and regulation by centrosomes. Disorganization of centrosomal proteins, including the nuclear mitotic apparatus (NuMA) protein and the molecular motor complex dynein/dynactin, can lead to chromosomal instability and developmental abnormalities. The present study reports the distribution and function of these proteins in human oocytes, zygotes and early embryos. A total of 239 oocytes, 90 zygotes and discarded embryos were fixed and analyzed with confocal microscopy for NuMA and dynactin distribution together with microtubules and chromatin. Microtubule-associated dynein-dependent transport functions were explored by inhibiting phosphatase and ATPase activity with sodium-orthovanadate (SOV). At germinal vesicle (GV) stages, NuMA was dispersed across the nucleoplasm. After GV breaks down, NuMA became cytoplasmic before localizing at the spindle poles in metaphase I and II oocytes. Aberrant NuMA localization patterns were found during oocyte in vitro maturation. After fertilization, normal and abnormal pronuclear stage zygotes and embryos displayed translocation of NuMA to interphase nuclei. SOV treatment for up to 2 h induced lower maturation rates with chromosomal scattering and ectopic localization of NuMA. Accurate distribution of NuMA is important for oocyte maturation, zygote and embryo development in humans. Proper assembly of NuMA is likely necessary for bipolar spindle organization and human oocyte developmental competence.

  6. Improved pregnancy rate in human in vitro fertilization with the use of a medium based on the composition of human tubal fluid.

    Science.gov (United States)

    Quinn, P; Kerin, J F; Warnes, G M

    1985-10-01

    Significantly more mouse zygotes developed to blastocysts in culture in a medium formulated on the composition of human tubal fluid (HTF) than in modified Tyrode's medium (T6). In a randomized 2 X 2 factorial trial of human in vitro fertilization that compared the two media and culture under oil versus culture in loosely capped tubes, significantly more clinical pregnancies (30% of 60 transfers) were obtained with HTF medium than with T6 medium (11% of 53 transfers). Decreasing the K+ content of HTF medium to that present in T6 medium significantly decreased the number of mouse zygotes that developed in culture. Modifying Ca++ levels had no effect. It is therefore likely that the higher K+ content in HTF medium is primarily responsible for the superiority of HTF medium over T6 medium, but other differences in the composition of the two media could contribute to the results observed.

  7. DESTAF: A database of text-mined associations for reproductive toxins potentially affecting human fertility

    KAUST Repository

    Dawe, Adam Sean

    2012-01-01

    The Dragon Exploration System for Toxicants and Fertility (DESTAF) is a publicly available resource which enables researchers to efficiently explore both known and potentially novel information and associations in the field of reproductive toxicology. To create DESTAF we used data from the literature (including over 10. 500 PubMed abstracts), several publicly available biomedical repositories, and specialized, curated dictionaries. DESTAF has an interface designed to facilitate rapid assessment of the key associations between relevant concepts, allowing for a more in-depth exploration of information based on different gene/protein-, enzyme/metabolite-, toxin/chemical-, disease- or anatomically centric perspectives. As a special feature, DESTAF allows for the creation and initial testing of potentially new association hypotheses that suggest links between biological entities identified through the database.DESTAF, along with a PDF manual, can be found at http://cbrc.kaust.edu.sa/destaf. It is free to academic and non-commercial users and will be updated quarterly. © 2011 Elsevier Inc.

  8. Female Fertility: Is it Safe to "Freeze?"

    Directory of Open Access Journals (Sweden)

    Lu Zhang

    2015-01-01

    Full Text Available Objective: To evaluate the safety and risk of cryopreservation in female fertility preservation. Data sources: The data analyzed in this review were the English articles from 1980 to 2013 from journal databases, primarily PubMed and Google scholar. The criteria used in the literature search show as following: (1 human; embryo; cryopreservation/freezing/vitrification, (2 human; oocyte/immature oocyte; cryopreservation/ freezing/vitrification, (3 human; ovarian tissue transplantation; cryopreservation/freezing/vitrification, (4 human; aneuploidy/DNA damage/epigenetic; cryopreservation/freezing/vitrification, and (5 human; fertility preservation; maternal age. Study selection: The risk ratios based on survival rate, maturation rate, fertilization rate, cleavage rate, implantation rate, pregnancy rate, and clinical risk rate were acquired from relevant meta-analysis studies. These studies included randomized controlled trials or studies with one of the primary outcome measures covering cryopreservation of human mature oocytes, embryos, and ovarian tissues within the last 7 years (from 2006 to 2013, since the pregnancy rates of oocyte vitrification were significantly increased due to the improved techniques. The data involving immature oocyte cryopreservation obtained from individual studies was also reviewed by the authors. Results: Vitrifications of mature oocytes and embryos obtained better clinical outcomes and did not increase the risks of DNA damage, spindle configuration, embryonic aneuploidy, and genomic imprinting as compared with fresh and slow-freezing procedures, respectively. Conclusions: Both embryo and oocyte vitrifications are safe applications in female fertility preservation.

  9. Nonlinear-dynamical arrhythmia control in humans.

    Science.gov (United States)

    Christini, D J; Stein, K M; Markowitz, S M; Mittal, S; Slotwiner, D J; Scheiner, M A; Iwai, S; Lerman, B B

    2001-05-08

    Nonlinear-dynamical control techniques, also known as chaos control, have been used with great success to control a wide range of physical systems. Such techniques have been used to control the behavior of in vitro excitable biological tissue, suggesting their potential for clinical utility. However, the feasibility of using such techniques to control physiological processes has not been demonstrated in humans. Here we show that nonlinear-dynamical control can modulate human cardiac electrophysiological dynamics by rapidly stabilizing an unstable target rhythm. Specifically, in 52/54 control attempts in five patients, we successfully terminated pacing-induced period-2 atrioventricular-nodal conduction alternans by stabilizing the underlying unstable steady-state conduction. This proof-of-concept demonstration shows that nonlinear-dynamical control techniques are clinically feasible and provides a foundation for developing such techniques for more complex forms of clinical arrhythmia.

  10. Molecular karyotyping of single sperm with nuclear vacuoles identifies more chromosomal abnormalities in patients with testiculopathy than fertile controls: implications for ICSI.

    Science.gov (United States)

    Garolla, Andrea; Sartini, Barbara; Cosci, Ilaria; Pizzol, Damiano; Ghezzi, Marco; Bertoldo, Alessandro; Menegazzo, Massimo; Speltra, Elena; Ferlin, Alberto; Foresta, Carlo

    2015-11-01

    from infertile patients showed a higher percentage of abnormal molecular karyotypes than controls (19.4 versus 7.7%, respectively, P abnormal karyotype in infertile men versus 18.3 and 5.0% in controls, respectively (both P abnormalities were found only in the LV category. An abnormal karyotype was never found in NV sperm from both patients and controls. The main limitation of this study is the low number of included subjects. Moreover, a time of writing we have no data regarding the ICSI outcome using LV, SV or NV sperm. This is the first study evaluating the molecular karyotype of single sperm selected by high-magnification microscopy and further confirmation of the data is needed. Our data showed that sperm from infertile patients with testicular impairment have a higher percentage of abnormal molecular karyotypes than sperm from fertile controls. Therefore, if confirmed, our data suggest that the use of individually retrieved NV sperm may improve ICSI outcome in infertile men with testicular damage. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Human/computer control of undersea teleoperators

    Science.gov (United States)

    Sheridan, T. B.; Verplank, W. L.; Brooks, T. L.

    1978-01-01

    The potential of supervisory controlled teleoperators for accomplishment of manipulation and sensory tasks in deep ocean environments is discussed. Teleoperators and supervisory control are defined, the current problems of human divers are reviewed, and some assertions are made about why supervisory control has potential use to replace and extend human diver capabilities. The relative roles of man and computer and the variables involved in man-computer interaction are next discussed. Finally, a detailed description of a supervisory controlled teleoperator system, SUPERMAN, is presented.

  12. Controlling human oesophagostomiasis in northern Ghana

    NARCIS (Netherlands)

    Ziem, Juventus Benogle

    2006-01-01

    This thesis describes aspects of the epidemiology and attempts to control infection and pathology due to the nematode parasite Oesophagostomum bifurcum . In northern Ghana and Togo O. bifurcum is an important parasite of humans; elsewhere it is predominantly seen as a parasite of non-human primates.

  13. Wolbachia endosymbionts and human disease control.

    Science.gov (United States)

    Slatko, Barton E; Luck, Ashley N; Dobson, Stephen L; Foster, Jeremy M

    2014-07-01

    Most human filarial nematode parasites and arthropods are hosts for a bacterial endosymbiont, Wolbachia. In filaria, Wolbachia are required for normal development, fertility and survival, whereas in arthropods, they are largely parasitic and can influence development and reproduction, but are generally not required for host survival. Due to their obligate nature in filarial parasites, Wolbachia have been a target for drug discovery initiatives using several approaches including diversity and focused library screening and genomic sequence analysis. In vitro and in vivo anti-Wolbachia antibiotic treatments have been shown to have adulticidal activity, a long sought goal of filarial parasite drug discovery. In mosquitoes, it has been shown that the presence of Wolbachia can inhibit the transmission of certain viruses, such as Dengue, Chikungunya, Yellow Fever, West Nile, as well as the infectivity of the malaria-causing protozoan, Plasmodium and filarial nematodes. Furthermore, Wolbachia can cause a form of conditional sterility that can be used to suppress populations of mosquitoes and additional medically important insects. Thus Wolbachia, a pandemic endosymbiont offers great potential for elimination of a wide-variety of devastating human diseases.

  14. Physiological Basis of Photosynthetic Function and Senescence of Rice Leaves as Regulated by Controlled-Release Nitrogen Fertilizer

    Institute of Scientific and Technical Information of China (English)

    NIE Jun; ZHENG Sheng-xian; DAI Pin-gan; XIAO Jian; YI Guo-ying

    2005-01-01

    The physiological mechanism of photosynthetic function and senescence of rice leaves was studied by using early rice variety Baliangyou 100 and late rice variety Weiyou 46, treated with controlled-release nitrogen fertilizer (CRNF), urea and no nitrogen fertilizer. CRNF showed obvious effects on delaying the senescence and prolonging photosynthetic function duration of rice leaves. Compared with urea, CRNF could significantly increase the chlorophyll content of functional leaves in both early and late rice varieties, and this difference between the treatments became larger as rice growth progressed; CRNF increased the activities of active oxygen scavenging enzymes super oxide dismutase (SOD) and peroxidase (POD), and decreased the accumulation amount of malondialdehyde (MDA) in functional leaves during leaf aging; Photosynthetic rate of functional leaves in CRNF treatment was significantly higher than that in urea treatment. The result also indicated that CRNF could effectively regulate the contents of indole-3-acetic acid (IAA) and abscisic acid (ABA) in functional leaves; IAA content was higher and ABA content was lower in CRNF treatment than those in urea treatment. Therefore, application of CRNF could increase the rice yield significantly due to these physiological changes in the functional leaves.

  15. [Effects of applying controlled-release fertilizer and its combination with urea on nitrous oxide emission during rice growth period].

    Science.gov (United States)

    Ji, Yang; Zhang, Xiao-Yan; Ma, Jing; Li, Xiao-ping; Xu, Hua; Cai, Zu-cong

    2011-08-01

    By the method of static chamber, a field experiment was conducted to study the effects of applying controlled-release fertilizer (CRF) and its combination with urea on the N2O emission during rice growth period. Four treatments, i.e., no fertilization (CK), urea (U), urea and CRF with a ratio of 3:7 (U+C), and CRF (C) were installed, and the N application rate in treatments U, U+C, and C was the same. Compared with treatment U, treatments U+C and C decreased the N2O emission during rice growth season by 40.4% and 59.6%, and decreased the emission at midseason aeration stage by 65.1% and 83.9%, respectively (P stage. Applying CRF increased rice yield, and the increment in treatments C and U+C was 7.8% and 9.8%, respectively, as compared to treatment U. Applying CRF delayed the peak time of soil inorganic nitrogen concentration, resulting in the reduction of N2O emission at midseason aeration stage. During rice growth season, no significant correlation was observed between N2O flux and soil Eh or soil temperature.

  16. Suppression of Ammonia Volatilization from Urea-Based Fertilizers Using Urease Inhibitors: A Reasonably Available Control Technology for Agriculture?

    Science.gov (United States)

    Robarge, W. P.

    2015-12-01

    Ammonia loss from fertilizers can impact formation of atmospheric aerosols, as well as contribute to nitrogen (N) deposition in terrestrial and aquatic ecosystems. Urea is the predominant form of N fertilizer used worldwide due to its high N content (46.6% N) and low cost. Once in contact with soil or vegetation, urea is hydrolyzed to ammonium via naturally occurring urease enzymes. Losses of N from surface applied urea as ammonia can exceed 30%. To address this issue, various physical and chemical mechanisms have been incorporated into granular urea. The most common approach is incorporation of urease inhibitors such as N-(n-butyl) thiophosphoric triamide (NBPT). We have been investigating ammonia volatilization from urea granules (+/- urease inhibitors) in various field and laboratory controlled experiments for the past several years. Laboratory experiments are conducted with a customized growth chamber system designed to continuously measure ammonia volatilization. Field measurements are conducted using a passive sampler technology with an acid-coated trap in PVC cylinders, or annular denuder technology using flow-through PVC chambers. Daily exchanges of acid-coated denuder tubes enhance the sensitivity of ammonia volatilization measurements for the urease-inhibitor treated product. Loss of N from commercial urea granules has ranged from 6 - ~ 35%, depending on ambient temperature. This loss typically occurs within the first 5-10 days under field conditions. Some urease-inhibitors can minimize loss of N via volatilization (technology for use in agriculture to reduce ammonia emissions.

  17. Types of slow/controlled release fertilizer and its quality evaluation method%缓/控释肥料类型及质量评价方法

    Institute of Scientific and Technical Information of China (English)

    杨红竹; 郑国亮; 刘海林; 林清火; 罗微

    2016-01-01

    缓/控释肥料具有减少养分淋失、挥发损失,提高肥料利用率等诸多优点,近年来在国内发展尤其迅速,是今后肥料发展的主要方向之一。介绍缓/控释肥料的概念、分类和质量评价方法,并对今后的研究方向进行展望。%S low/controlled release fertilizers has many advantages, such as it can improve the uptake of nutrients by plants, reduce possible losses of nutrients and losses of ammonia. In recent years, slow/controlled release fertilizers develops fastly in domestic market. Slow/controlled release fertilizers is one of the main direction for the future development of fertilizer. This paper introduceds the concept, classification and quality evaluation method of slow/controlled release fertilizer, and looks forward to the future research.

  18. Research on Application Effect of Controlled-Release Fertilizer and Traditional Fertilizer on Carnation in Yinchuan City%控释肥与常规化肥在银川市康乃馨上的应用效果研究

    Institute of Scientific and Technical Information of China (English)

    卜燕燕

    2016-01-01

    The effects of controlled-release fertilizer and traditional fertilizer on carnation showed that the effect of controlled-release fertilizer was better than traditional fertilizer.Using controlled-release fertilizer could reduce the number of fertilizer,labor and the labor intensity,increase the ratio of outputs to inputs objectively.%选用控释肥和常规化肥种植康乃馨,结果表明:控释肥的效果优于常规化肥。控释肥减少了追肥、用工的次数,降低了劳动强度,客观上增大了产投比。

  19. Fertilizer and sanitary quality of digestate biofertilizer from the co-digestion of food waste and human excreta.

    Science.gov (United States)

    Owamah, H I; Dahunsi, S O; Oranusi, U S; Alfa, M I

    2014-04-01

    This research was aimed at assessing the fertilizer quality and public health implications of using digestate biofertilizer from the anaerobic digestion of food wastes and human excreta. Twelve (12) kg of food wastes and 3kg of human excreta were mixed with water in a 1:1 w/v to make 30-l slurry that was fed into the anaerobic digester to ferment for 60days at mesophilic temperature (22-31°C). Though BOD, COD, organic carbon and ash content in the feedstock were reduced after anaerobic digestion by 50.0%, 10.6%, 74.3% and 1.5% respectively, nitrogen, pH and total solids however increased by 12.1%, 42.5% and 12.4% respectively. The C/N ratios of the feedstock and compost are 135:1 and 15.8:1. The residual total coliforms of 2.10×10(8)CFU/100ml in the digestate was above tolerable limits for direct application on farmlands. Microbial analysis of the digestate biofertilizer revealed the presence of Pseudomonas, Klebsiella, Clostridium, Bacillus, Bacteroides, Penicillum, Salmollena, and Aspergillus. Klebsiella, Bacillus, Pseudomonas, Penicillum and Aspergillus can boost the efficiency of the biofertilizer through nitrogen fixation and nutrient solubility in soils but Klebsiella again and Salmollena are potential health risks to end users. Further treatment of the digestate for more efficient destruction of pathogens is advised. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Effects of polybrominated diphenyl ethers on thyroid hormone, neurodevelopment and fertility in rodents and humans

    Directory of Open Access Journals (Sweden)

    Marta Czerska

    2013-08-01

    Full Text Available Polybrominated diphenyl ethers (PBDEs are used as flame retardants. Due to their widespread use in many consumer products, PBDEs can be found in food as well as in the environment. Their presence has also been found in the human serum, human adipose tissue and human breast milk. Results of experimental studies suggest that the presence of PBDE in the environment is not neutral to our health. In rats and mice exposed to PBDE disturbances in thyroid hormone homeostasis and reproductive system such as changes in reproductive organs weight and disorders in sperm motility and motion were found. In rodents, pre- and postnatal exposure to PBDE can cause neurobehavioral effects. Also in humans disturbances in thyroid hormone system, weight of reproductive organs and concentrations of sex hormones associated with PBDEs serum concentrations were found. Exposure to PBDEs during pregnancy may lead to slower mental and psychomotor development in infants. In this paper the results of previous animal a nd human studies are reviewed.

  1. 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

  2. Effects of organic and chemical fertilizer on plant nutritional status and soil fertility of tomatoes grown under greenhouse condition

    OpenAIRE

    DEMİRTAŞ, Elif Işıl; ÖKTÜREN ASRİ, Filiz; Cevdet Fehmi ÖZKAN; Nuri ARI

    2012-01-01

    The effect of some plant originated liquid organic fertilizer on soil fertility and plant nutritional status of tomato plants were investigated. The experiment was planned to compare the control, organic fertilizer, chemical fertilizer, 1/1chemical+organic fertilizer, ½chemical+organic fertilizer, chemical fertilizer+foliar organic fertilizer application. The trial was conducted in randomised complete block design with four replications. Plant and soil samples were analyzed. According to the ...

  3. Control of human trophoblast function

    Directory of Open Access Journals (Sweden)

    Biondi Carla

    2007-02-01

    Full Text Available Abstract The trophoblast, i.e. the peripheral part of the human conceptus, exerts a crucial role in implantation and placentation. Both processes properly occur as a consequence of an intimate dialogue between fetal and maternal tissues, fulfilled by membrane ligands and receptors, as well as by hormone and local factor release. During blastocyst implantation, generation of distinct trophoblast cell types begins, namely the villous and the extravillous trophoblast, the former of which is devoted to fetal-maternal exchanges and the latter binds the placental body to the uterine wall. Physiological placentation is characterized by the invasion of the uterine spiral arteries by extravillous trophoblast cells arising from anchoring villi. Due to this invasion, the arterial structure is replaced by amorphous fibrinoid material and endovascular trophoblastic cells. This transformation establishes a low-resistance, high-capacity perfusion system from the radial arteries to the intervillous space, in which the villous tree is embedded. The physiology of pregnancy depends upon the orderly progress of structural and functional changes of villous and extravillous trophoblast, whereas a derangement of such processes can lead to different types of complications of varying degrees of gravity, including possible pregnancy loss and maternal life-threatening diseases. In this review we describe the mechanisms which regulate trophoblast differentiation, proliferation, migration and invasiveness, and the alterations in these mechanisms which lead to pathological conditions. Furthermore, based on the growing evidence that proper inflammatory changes and oxidative balance are needed for successful gestation, we explain the mechanisms by which agents able to influence such processes may be useful in the prevention and treatment of pregnancy disorders.

  4. Low fertility, human capital, and economic growth: The importance of financial education and job retraining

    Directory of Open Access Journals (Sweden)

    Naohiro Ogawa

    2013-10-01

    Full Text Available Background: International research has shown that workers have a rather low level of financial literacy. Financial literacy is associated with lifetime planning and saving for retirement. This article focuses on the role of financial literacy in the demand for human capital and on-the-job training among older workers in Japan. Workers with higher levels of financial literacy are more likely to demand human capital, plan to enter training programs, and desire to work after retirement. Objective: Does financial literacy affect the demand for additional human capital among older Japanese workers? How does the level of financial literacy affect the age of retirement and plans for working after retirement from a career job in Japan? Methods: This paper analyzes data from a national survey of Japanese employees. We estimate the effect of financial literacy on the demand for additional human capital to remain competitive for promotions and for finding employment after retirement. Results: Higher levels of financial literacy are associated with greater demand for additional human capital and for participation in on-the-job training programs among older workers in Japan. Conclusions: Given the rapid aging of the Japanese population and the decline in the total population, providing employment opportunities for older workers (ages 60 and older is a key to sustaining economic growth and per capita income. The analysis indicates that greater levels of financial literacy are associated with a desire for more training and human capital. Thus, enhancing the level of financial literacy among older workers may be a key to maintaining economic wellbeing.

  5. Bio-based Interpenetrating Network Polymer Composites from Locust Sawdust as Coating Material for Environmentally Friendly Controlled-Release Urea Fertilizers.

    Science.gov (United States)

    Zhang, Shugang; Yang, Yuechao; Gao, Bin; Wan, Yongshan; Li, Yuncong C; Zhao, Chenhao

    2016-07-20

    A novel polymer-coated nitrogen (N) fertilizer was developed using bio-based polyurethane (PU) derived from liquefied locust sawdust as the coating material. The bio-based PU was successfully coated on the surface of the urea fertilizer prills to form polymer-coated urea (PCU) fertilizer for controlled N release. Epoxy resin (EP) was also used to further modify the bio-based PU to synthesize the interpenetrating network (IPN), enhancing the slow-release properties of the PCU. The N release characteristics of the EP-modified PCU (EMPCU) in water were determine at 25 °C and compared to that of PCU and EP-coated urea (ECU). The results showed that the EP modification reduced the N release rate and increased the longevity of the fertilizer coated with bio-based PU. A corn growth study was conducted to further evaluate the filed application of the EMPCU. In comparison to commercial PCU and conventional urea fertilizer, EMPCU was more effective and increased the yield and total dry matter accumulation of the corn. Findings from this work indicated that bio-based PU derived from sawdust can be used as coating materials for PCU, particularly after EP modification. The resulting EMPCU was more environmentally friendly and cost-effective than conventional urea fertilizers coated by EP.

  6. Allometric control of human gait

    Science.gov (United States)

    Griffin, Lori Ann

    The purpose of the study was to extract the information contained in the fluctuations in the stride interval time series and the correlation properties of walking. To determine if the time series had memory or long-time correlation properties, the decay (loss) of correlation of the data across time was studied. The information acquired was to determine if control of walking could be better understood, by studying statistics of stride intervals. Furthermore, it was determined if the time series for walking was stable enough to establish a baseline for future studies. Allometric analysis was done on relaxed walking for 10 individuals. The data obtained during the experiments consisted of the time interval for a given stride and the number of strides in the sequence of steps. The maximal extension of the right leg, the ``stride interval'' versus the stride number, yielded a graph that has all the characteristics of a time series. Insight into the stride interval time series was obtained using relative dispersion, also know as the coefficient of variation, the ratio of the standard deviation to the mean. The results indicated memory in the control of walking for all subjects. Furthermore, memory was not maintained once the data was randomized suggesting the order of strides is important. The amount of memory differed for each subject, whereby some subjects had significant memory (high correlation coefficients = 0.693) while others showed low correlation coefficients. The relative dispersion for all subjects decreased with increasing aggregation number. This straight line with a negative slope depicted an inverse power-law relation between the relative dispersion and the aggregation number. The data does not have a dominant scale and can be evaluated on many scales without information lost. Although these data alone do not establish a baseline, the data analyzed using allometric analysis appears sufficiently stable to establish a baseline norm for walking. Finally, the

  7. HUMAN-SIMULATING VEHICLE STEERING CONTROL ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    XU Youchun; LI Keqiang; CHANG Ming; CHEN Jun

    2006-01-01

    A new vehicle steering control algorithm is presented. Unlike the traditional methods do,the algorithm uses a sigmoid function to describe the principle of the human driver's steering strategy.Based on this function, a human simulating vehicle steering model, human-simulating steering control(HS) algorithm is designed. In order to improve the adaptability to different environments, a parameter adaptive adjustment algorithm is presented. This algorithm can online modify the value of the key parameters of the HS real time. HS controller is used on a vehicle equipped with computer vision system and computer controlled steering actuator system, the result from the automatic vehicle steering experiment shows that the HS algorithm gives good performance at different speed, even at the maximum speed of 172 km/h.

  8. Human right to water and conventionality control

    Directory of Open Access Journals (Sweden)

    Adriana N. Martínez

    2013-12-01

    Full Text Available Humanity faces the challenge of achieving the sustainability of water resources supply for the satisfaction of human needs and ofensuring the sustainability of the natural ecosystems for the achievement of sustainable human development and the quality of life of present and future generations. For this reason the recognition of access to water as a Human Right has fundamental significance. We proceed to analyze the international instruments that provide content and legal basis to the human right to water and the obligations of States. In this context, we deal with the constitutional reception of human right to water in Argentina in the constitutional reform of 1994 and the control of conventionality as guarantor of access to water, which has led to different domestic courts to consider cases in which a violation ofthe right to water was proved.

  9. [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.

  10. Effects of Controlled-release Fertilizer Application with Cow Manure on Yield (Brassica napa L), Drainage Water Quality and N2O Emission

    OpenAIRE

    AMKHA, Suphachai; Inubushi, Kazuyuki

    2009-01-01

    Nitrogen (N) supply is a major factor controlling the yield and quality of vegetables. The purpose of the present study was to determine the effects of different rates of controlled-release N fertilizers (CRFs) and urea applications with cow manure on a) yield (Brassica napa L.), b) nitrate leaching from soil, and c) N2O flux in surface soil. The fertilizers were applied according to the following 6 type-rate combinations: 1) CM-CDU 450 (kg ha-1), 2) LP 450, 3) urea 450, 4) CM-CDU 360, and 5)...

  11. Moderate ovarian stimulation does not increase the incidence of human embryo chromosomal abnormalities in in vitro fertilization cycles.

    Science.gov (United States)

    Labarta, Elena; Bosch, Ernesto; Alamá, Pilar; Rubio, Carmen; Rodrigo, Lorena; Pellicer, Antonio

    2012-10-01

    A high chromosomal abnormalities rate has been observed in human embryos derived from in vitro fertilization (IVF) treatments. The real incidence in natural cycles has been poorly studied, so whether this frequency may be induced by external factors, such as use of gonadotropins for ovarian stimulation, remains unknown. We conducted a prospective cohort study in a University-affiliated private infertility clinic with a comparison between unstimulated and stimulated ovarian cycles in the same women. Preimplantation genetic screening by fluorescence in situ hybridization was performed in all viable d 3 embryos. The primary objective was to compare the incidence of embryo chromosomal abnormalities in an unstimulated cycle and in an ulterior moderate ovarian stimulated cycle. Secondary outcome measures were embryo quality, blastocyst rate of biopsied embryos, number of normal blastocysts per donor, type of chromosomal abnormalities, and clinical outcome. One hundred eighty-five oocyte donors were initially recruited for the unstimulated cycle, and preimplantation genetic screening could be performed in 51 of them, showing 35.3% of embryo chromosomal abnormalities. Forty-six of them later completed a stimulated cycle. The sperm donor sample was the same for both cycles. The proportion of embryos displaying abnormalities in the unstimulated cycle was 34.8% (16 of 46), whereas it was 40.6% (123 of 303) in the stimulated cycle with risk difference=5.8 [95% confidence interval (CI)=-20.6-9.0], and relative risk=1.17 (95% CI=0.77-1.77) (P=0.45). When an intrasubject comparison was made, the abnormalities rate was 34.8% (95% CI=20.5-49.1) in the unstimulated cycle and 38.2% (95% CI=30.5-45.8) in the stimulated cycle [risk difference=3.4 (95% CI=-17.9-11.2); P=0.64]. No differences were observed for embryo quality and type of chromosomal abnormalities. Moderate ovarian stimulation in young normo-ovulatory women does not significantly increase the embryo aneuploidies rate in in

  12. Isolation of Promoters and Fragments of Genes Controlling Endosperm Development Without Fertilization in Arabidopsis and Engineering of the Antisense Constructions

    Directory of Open Access Journals (Sweden)

    Grigory A. Gerashchenkov

    2015-06-01

    Full Text Available Apomixis is asexual seed reproduction without both meiosis and fertilization based on the complex developmental processes such as apomeiosis, parthenogenesis and specific endosperm development. This investigation is aimed at engineering of apomixis in Arabidopsis thaliana with sexual seed reproduction. The fragments of known genes of endosperm formation MEA, FIE, FIS2 and gene of apomeiosis DYAD (as control were isolated using Q5 high fidelity DNA polymerase. These gene fragments of interest at the antisense orientation were fused with isolated constitutive and meiosis specific promoters of Arabidopsis at NcoI sites. The fused promoter-gene fragment modules were cloned in pCambia1301 at SalI cites. The engineered constructions will be used for the floral dip transformation of Arabidopsis and down regulation of these genes at engineering of apomixis.

  13. Con A-binding protein Zn-α2-glycoprotein on human sperm membrane is related to acrosome reaction and sperm fertility.

    Science.gov (United States)

    Liu, Y; Qu, F; Cao, X; Chen, G; Guo, Q; Ying, X; Guo, W; Lu, L; Ding, Z

    2012-04-01

    Fertilization, the recognition and fusion between spermatozoa and oocyte, involves various molecules on the spermatozoa and oocyte membranes. Concanavalin A (ConA)-binding proteins may be one of the molecules involved in mammal spermatozoa fertilization; however, their structure and function remain largely unknown. Here, we initially identified a ConA-binding protein, Zn-α2-glycoprotein (ZAG), involved in regulating the acrosome reaction (AR) of human spermatozoa. ZAG is localized on the pre-equatorial region covering the acrosome, neck and tail (some parts of middle piece and principal piece respectively) regions of the acrosome intact human spermatozoa, and disappears in the acrosomal region of the acrosome-reacted spermatozoa. Polyclonal antibodies against human recombinant ZAG significantly reduced the AR and sperm capability binding to human zona pellucida or penetration into zona-free hamster oocytes. Furthermore, assessment of the signaling pathways regulated by ZAG revealed that ZAG affects sperm AR through both the cAMP/PKA and PKC pathways. These results indicate that ZAG, which is present on the human sperm membrane, plays a critical role in the AR and subsequently, may be involved in sperm fertility.

  14. Short-term and long-term effects of weed control and fertilization on growth and wood anatomy of a Populus deltoides clone

    Directory of Open Access Journals (Sweden)

    Silvia Estela Monteoliva

    2015-04-01

    Full Text Available Aims of study: The short- and long-term effects of weed control and fertilization on growth and wood anatomy of 10-y-old Populus deltoides were investigated. Weed control and fertilization usually leads to an increase the growth rate of trees, and consequently, a possible modification in the quality of produced wood. Area of study: We analyzed trees from an experimental plantation in Buenos Aires, Argentina (34° 50’ S Lat; 60° 30’ W Long. Methods: 32 trees from three treatments: mechanical weed control (M, chemical and mechanical weed control (CHM and fertilized plus chemical and mechanical weed control (CHM-F were analyzed. Basal area, fibre morphology, cell wall area and vessel size were measured in the growth ring 1, 3 and 10. Results: differences on wood anatomy among treatments were mainly observed at the third year (short-term effect. Long-term negative effects were not observed. Fertilized trees had greater proportion and quality of wood closer to pith. Research highlights: fibre and vessel differences seen in CHM and CHM-F compared to controls in year 3 could be interpreted as evidence of maturation in cambial development (thicker, longer and wider fibres and greater vessels. The CHM-F treatment had a greater proportion of wood that showed characteristics of more mature wood.

  15. 我国缓/控释肥料的应用进展%Application Development of Slow/Controlled Released Fertilizer in China

    Institute of Scientific and Technical Information of China (English)

    朱明旭

    2012-01-01

    Slow/controlled released fertilizer has become a hot research topic in recent years. The effects on crop yield, traits, quality and fertilizer utilization were the main direction of its application research. The application progress of slow/controlled released fertilizer in China in recent years was summarized.%缓/控释肥料是近年来的一个研究热点.它对作物产量、性状、品质以及肥料利用率等的影响是其应用研究的主要方向.笔者总结了近年来我国缓/控释肥料的应用进展.

  16. 硅藻土对肥料的控释作用研究%Features of Controlled Release of Diatomite-coated Compound Fertilizers

    Institute of Scientific and Technical Information of China (English)

    张秀兰; 栗印环; 王晓晶; 申盼

    2014-01-01

    用硅藻土作为包裹剂,以正硅酸乙酯作为黏结保护层,将氮、钾、磷肥在不同分散剂中进行包裹处理,利用红外光谱分析样品的官能团,通过滴淋实验测试肥料的控释性能。结果表明:硅藻土对易溶的氮、钾肥有良好的缓释效果,而对难溶的磷肥有促释效果,用正硅酸乙酯为黏结保护层的氮、钾肥控释作用较好。%The diatomite was used as wrapping reagent and tetraethyl orthosilicate as adhesive to link layers of diat-omite,and thus the compound fertilizer of diatomite coated nitrogenous,potassium and phosphate fertilizers were pre-pared in different dispersants. The characterization of functional groups of the samples were performed with Infrared spectrum. The controlled release property was tested by means of drop-leaching experiment. The results showed that the diatomite exhibited slowly releasing effect for the soluble N and K fertilizers. However,the diatomite promoted the re-lease of insoluble P fertilizer. The effect of controlled release N and K fertilizers was good with the tetraethyl orthosili-cate as binder.

  17. Fertility Rates of Ewes Treated with Medroxyprogesterone and Injected with Equine Chorionic Gonadotropin plus Human Chorionic Gonadotropin in Anoestrous Season

    Directory of Open Access Journals (Sweden)

    I. W. Santos

    2010-01-01

    Full Text Available The aim of the present paper was to investigate the efficiency of the equine chorionic gonadotropin (eCG plus human chorionic gonadotropin (hCG associated with medroxyprogesterone acetate (MAP to estrous ewes synchronization. Ninety Texel ewes were investigated during seasonal anoestrous. The ewes received intravaginal sponges containing MAP (60 mg for nine days. At the time of sponges' withdrawal, the ewes were divided into three groups (G: (1 receiving 2 mL of saline i.m. (n=30, (2 receiving eCG 400 IU i.m. (n=30, and (3 receiving eCG 400 IU plus hCG 200 IU i.m. (n=30. Twelve h after sponges' removal, teaser rams were used to estrus check and remained with the ewes for 96 h. The artificial insemination was made with fresh semen 10 h after estrus detection. The effect of the treatment was not significant for the estrous rates among the groups: 73%, 90%, and 86%, respectively. The main effect was observed in the pregnancy and lambing rates among the groups: 70%, 86%, 56%, and 80%, 120%, 56%, respectively. Based on these results from our study, the use of the MAP—eCG is the best choice to improve the fertility rate on ewes.

  18. Predictive value of early serum beta-human chorionic gonadotrophin for the successful outcome in women undergoing in vitro fertilization

    Directory of Open Access Journals (Sweden)

    Neeta Singh

    2013-01-01

    Full Text Available Aims: Pregnancies achieved by in vitro fertilization (IVF are at increased risk of adverse outcome. The main objective of this study was to evaluate the predictive value of β-human chorionic gonadotrophin (β-HCG and age of the patient for the successful outcome in IVF. Materials and Methods: A retrospective study was done in 139 pregnancies after IVF at single IVF center from June 2007 to July 2012. The age of the patient and initial serum values of β-HCG on day 14 of embryo transfer were correlated with ongoing pregnancy (>12 weeks gestation. Results: The β-HCG level on day 14 of more than 347 mIU/ml has a sensitivity of 72.2% and specificity of 73.6% in prediction of pregnancy beyond 12 weeks period of gestation. Positive likelihood ratio (LR is 2.74 and negative LR is 0.37, (receiver operating characteristic area = 0.79. Discussion: In IVF cycles, there is a lot of stress on the couples while the cycle is going on. There was a positive correlation between the higher values of early serum β-HCG levels and ongoing pregnancy. Hence, it can be used as an independent predictor of a successful outcome of IVF cycle. Conclusion: We concluded from our study that early serum β-HCG can be used as a predictor of a successful outcome in IVF.

  19. Natural fertility in the Philippines.

    Science.gov (United States)

    Aquino, E G

    1982-01-01

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

  20. Shared resource control between human and computer

    Science.gov (United States)

    Hendler, James; Wilson, Reid

    1989-01-01

    The advantages of an AI system of actively monitoring human control of a shared resource (such as a telerobotic manipulator) are presented. A system is described in which a simple AI planning program gains efficiency by monitoring human actions and recognizing when the actions cause a change in the system's assumed state of the world. This enables the planner to recognize when an interaction occurs between human actions and system goals, and allows maintenance of an up-to-date knowledge of the state of the world and thus informs the operator when human action would undo a goal achieved by the system, when an action would render a system goal unachievable, and efficiently replans the establishment of goals after human intervention.

  1. Proprioceptive Control of Human Movement. The Human Movement Series.

    Science.gov (United States)

    Dickinson, John

    Various research studies concerned with the feedback from proprioceptors which accompany movement and the way in which this information is relevant to the control of activity are brought together in this volume. It is intended for the use of those who have some basic knowledge of human anatomy and physiology as well as an acquaintance with…

  2. Highly purified human-derived follicle-stimulating hormone (Bravelle® has equivalent efficacy to follitropin-beta (Follistim ® in infertile women undergoing in vitro fertilization

    Directory of Open Access Journals (Sweden)

    Webster Bobby W

    2003-10-01

    Full Text Available Abstract Background These data compare the efficacy and safety of highly purified human-derived follicle-stimulating hormone (Bravelle(R and recombinant follitropin-β (Follistim(R in women undergoing in vitro fertilization. Methods This report describes the pooled data from two, nearly identical, randomized, controlled, parallel-group, multicenter studies conducted in a total of 19 academic and private IVF-ET centers in the United States. Infertile premenopausal women underwent pituitary down-regulation using leuprolide acetate followed by a maximum of 12 days of subcutaneous Bravelle(R (n = 120 or Follistim(R (n = 118, followed by administration of human chorionic gonadotropin, oocyte retrieval and embryo transfer. The primary efficacy measure was the mean number of oocytes retrieved; secondary efficacy measures included the total dose and duration of gonadotropin treatment; peak serum estradion levels; embryo transfer and implantation rates; chemical, clinical and continuing pregnancies; and live birth rates. All adverse events were recorded and injection site pain was recorded daily using a patient, self-assessment diary. Results Similar efficacy responses were observed for all outcome parameters in the two treatment groups. Although patients receiving Bravelle(R consistently reported a greater number of chemical, clinical and continuing pregnancies, as well as an increased rate of live birth, the data did not attain statistical significance (P > 0.05. The overall incidence of adverse events was similar in both groups, but compared to Follistim(R, injections of Bravelle(R were reported by patients to be significantly less painful (P Conclusions Bravelle(R and Follistim(R had comparable efficacy in controlled ovarian hyperstimulation in women undergoing IVF-ET. There were no differences in the nature or number of adverse events between the treatment groups although Bravelle(R injections were reported to be significantly less painful.

  3. Passive Control Architecture for Virtual Humans

    CERN Document Server

    Rennuit, Antoine; Merlhiot, Xavier; Andriot, Claude; Guillaume, François; Chevassus, Nicolas; Chablat, Damien; Chedmail, Patrick

    2007-01-01

    In the present paper, we introduce a new control architecture aimed at driving virtual humans in interaction with virtual environments, by motion capture. It brings decoupling of functionalities, and also of stability thanks to passivity. We show projections can break passivity, and thus must be used carefully. Our control scheme enables task space and internal control, contact, and joint limits management. Thanks to passivity, it can be easily extended. Besides, we introduce a new tool as for manikin's control, which makes it able to build passive projections, so as to guide the virtual manikin when sharp movements are needed.

  4. 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.

  5. Discussion on the Green Tax Stimulation Measure of Nitrogen Fertilizer Non-Point Source Pollution Control - Taking the Dongting Lake Area in China as a Case

    Institute of Scientific and Technical Information of China (English)

    XIANG Ping-an; ZHOU Yan; HUANG Huang; ZHENG Hua

    2007-01-01

    A study on designing the tax of nitrogen fertilizer can provide a new method for controlling nitrogen fertilizer non-point source pollution. The tax design of nitrogen fertilizer was discussed by utilizing the external theory and the demand elasticity theory. The results indicated that the coefficient of price elasticity of nitrogen fertilizer demand is -0.21, which instructed that the market demand is in lack of elasticity in the short period and the impact of nitrogen fertilizer manufacturers is subtle. The 11 counties (cities and boroughs) in the Dongting Lake area in China, where the farmland nitrogen application surpassed the average ecological fertilization dosage, is listed to the taxation scope of nitrogen fertilizer tax. The environment loss will reduce 0.07 hundred million RMB yuan and the revenue will increase 0.89 hundred million RMB yuan in the country after levying on nitrogen fertilizer. The loss, which was brought by the decreasing food supplies production, will be 0.58 hundred million RMB yuan and the net social benefit will be 0.38 hundred million RMB yuan following revenue collection. The variation scope of the increasing expenditure of farmers will range from 0.95 to 1.49%. The variation scope of the income of farmers will range from -8.41 to 6.44%. The 5 areas, Yunxi Borough, Junshan Borough, Hanshou County, Jinshi City, and Ziyang Borough, had an increase in food supplies production after the revenue collection. The environment loss will reduce 0.01 hundred million RMB yuan and the revenue will increase 0.16 hundred million RMB yuan in the country after levying on nitrogen fertilizer. The economic benefits, which was brought by the increasing cereals production, will be 0.67 hundred million RMB yuan and the net social benefit will be 0.84 hundred million RMB yuan after revenue collection. The variation scope of the increasing expenditure of farmers will range from 0.95 to 1.06%. The variation scope of the increasing income of farmers will

  6. 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

  7. Evaluation of a soil incubation method to characterize nitrogen release patterns of slow- and controlled-release fertilizers.

    Science.gov (United States)

    Medina, L Carolina; Sartain, Jerry B; Obreza, Thomas A; Hall, William L; Thiex, Nancy J

    2014-01-01

    Several technologies have been proposed to characterize the nutrient release patterns of slow-release fertilizers (SRF) and controlled-release fertilizers (CRF) during the last few decades. These technologies have been developed mainly by manufacturers, and are product-specific, based on the regulation and analysis of each SRF and CRF product. Despite previous efforts to characterize SRF and CRF materials, no standardized, validated method exists to assess their nutrient release patterns. However, the increased production and distribution of these materials in specialty and nonspecialty markets requires an appropriate method to verify product claims and material performance. A soil incubation column leaching procedure was evaluated to determine its suitability as a standard method to estimate nitrogen (N) release patterns of SRFs and CRFs during 180 days. The influence of three soil/sand ratios, three incubation temperatures, and four soils on method behavior was assessed using five SRFs and three CRFs. In general, the highest soil/sand ratio increased the N release rate of all materials, but this effect was more marked for the SRFs. Temperature had the greatest influence on N release rates. For CRFs, the initial N release rates and the percentage N released/day increased as temperature increased. For SRFs, raising the temperature from 25 to 35 degreesC increased initial N release rate and the total cumulative N released, and almost doubled the percentage released/day. The percentage N released/day from all products generally increased as the texture of the soil changed from sandy to loamy (lowa>California>Pennsylvania>Florida). The soil incubation technique was demonstrated to be robust and reliable for characterizing N release patterns from SRFs and CRFs. The method was reproducible, and variations in soil/sand ratio, temperature, and soil had little effect on the results.

  8. Studies on the Mechanism of Single Basal Application of Controlled-Release Fertilizers for Increasing Yield of Rice (Oryza sativa L.)

    Institute of Scientific and Technical Information of China (English)

    TANG Shuan-hu; YANG Shao-hai; CHEN Jian-sheng; XU Pei-zhi; ZHANG Fa-bao; AI Shao-ying; HUANG Xu

    2007-01-01

    This paper was to explore the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice (Oryza sativa L.). Pot trials and cylinder trials were carried out from 2002 to 2005 to study the influences of single basal application of 3 controlled-release fertilizers on the changes of soil available N, root development, senescence and lodging resistance at late growth stages. Results showed that at 30 days after fertilization, single basal application of controlled-release fertilizers coated with vegetal-substance (CRF1) and polymer materials (CRF3) increased soil available N to 12.0 and 147.9%, respectively, in comparison to split fertilization of rice-specific fertilizer (RSF1). Treatments of the two CRFs obviously benefited the development of root system, resulting in greater rice root weights with extensive distribution and higher root activity. In addition, the two CRF treatments, in comparison to RSF1, enhanced chlorophyll consents of the flag leaves to 9.5 and 15.5%, and soluble protein up to 89.7 and 108.0% respectively. Application of the two CRFs also made the base of rice stems strong and large, declined the proportion of shoot and root, increased root depth index. Though relatively low K rate, single basal application of the CRF3 coated with NH4MgPO4 could also promote the development of root system, enhance root activity and some physiological functions of flag leaves. Based on these results, it was concluded that major mechanisms for increasing rice yield by single basal application of the CRFs should be attributed to grater soil available N supply, superior development of root systems, better nutrient absorption capacity, slower senescence and enhancement of lodging resistance at late stages.

  9. 液体注肥器定量控制系统的设计%Design of Weighing Control System of Liquid Fertilizer Injector

    Institute of Scientific and Technical Information of China (English)

    邹伟; 王秀; 张睿; 郝强

    2013-01-01

      针对目前液体施肥机的不足,设计了可以定量控制施肥量的注肥控制系统。系统采用电机带动离心泵输送液态肥料,通过计算注肥器管道中流量传感器的脉冲信号,获取系统实际排出的液体体积,根据实际施肥量与设定值的差值控制电机运转,从而实现根据实际需要精确控制施肥量。实际运行结果表明,该系统运行可靠,系统对施肥控制量误差相对比较小,可以在一定程度上实现精准注肥,减少肥料浪费。%Because of deficiency of the liquid fertilizer applicator , the weighing control system of liquid fertilizer injector was designed .The liquid fertilizer is delivered by a centrifugal pump which adopts the motor drive .Through the calcula-tion of the flow sensor pulse signal in the pipe , the controller gains the actual discharged liquid volume .The difference between the actual value and the set value determines whether the motor running .The fertilizer control error of the system is relatively small , the crops can be fertilization accurately and the fertilizer waste can be reduced in a sense .

  10. Thermal post-treatment alters nutrient release from a controlled-release fertilizer coated with a waterborne polymer

    Science.gov (United States)

    Zhou, Zijun; Du, Changwen; Li, Ting; Shen, Yazhen; Zhou, Jianmin

    2015-09-01

    Controlled-release fertilizers (CRF) use a controlled-release technology to enhance the nutrient use efficiency of crops. Many factors affect the release of nutrients from the waterborne polymer-coated CRF, but the effects of thermal post-treatments remain unclear. In this study, a waterborne polyacrylate-coated CRF was post-treated at different temperatures (30 °C, 60 °C, and 80 °C) and durations (2, 4, 8, 12, and 24 h) after being developed in the Wurster fluidized bed. To characterize the polyacrylate membrane, and hence to analyze the mechanism of nutrient release, Fourier transform mid-infrared spectroscopy, scanning electron microscopy, and atomic force microscopy were employed. The nutrient-release model of CRF post-treated at 30 °C was the inverse “L” curve, but an increased duration of the post-treatment had no effect. The nutrient-release model was “S” curve and nutrient-release period was enhanced at higher post-treatment temperatures, and increased post-treatment duration lengthened slowed nutrient release due to a more compact membrane and a smoother membrane surface as well as a promoted crosslinking action. CRF equipped with specified nutrient-release behaviors can be achieved by optimizing the thermal post-treatment parameters, which can contribute to the development and application of waterborne polymer-coated CRF and controlled-release technologies.

  11. Evaluation of the interactions between chitosan and humics in media for the controlled release of nitrogen fertilizer.

    Science.gov (United States)

    Araújo, Bruno R; Romão, Luciane P C; Doumer, Marta E; Mangrich, Antonio S

    2017-04-01

    The aim of this study was to evaluate the interactions of peat, humic acids, and humin with urea dispersed in chitosan, in systems intended for the controlled release of urea. Spheres of chitosan with humic material and urea intentionally added to the media were prepared and characterized by means of elemental analysis (CHN), electron paramagnetic resonance (EPR), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The spheres possessed functional groups related to humic substances that interacted with the chitosan, and the presence of urea in the media was also confirmed after it has been added. Release experiments demonstrated that the samples released urea in a controlled manner that was dependent on pH, increasing in the order: pH 2.5 < pH 4.0 < pH 9.0. In soil experiments, the degree of release of urea (α) increased over time, with values of 0.44 for chitosan-humic acids-urea (CHAU), 0.48 for chitosan-peat-urea (CPTU), and 0.67 for chitosan-humin-urea (CHMU) obtained in the first day of the experiment. The release of urea did not exceed 70% after 7 days. The results demonstrated the potential of using peat, humic acids, and humin, in combination with chitosan, in order to manufacture controlled release urea fertilizers and contribute to reducing adverse environmental and economic impacts. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Rethinking optimal control of human movements

    OpenAIRE

    Huh, Dongsung

    2012-01-01

    The complex bio-mechanics of human body is capable of generating an unlimited repertoire of movements, which on one hand yields highly versatile motor behavior but on the other hand presents a formidable control problem for the brain. Understanding the computational process that allows us to easily perform various motor tasks with a high degree of coordination is of central interest to both neuroscience and robotics control. In recent decades, it became widely accepted that the observed movem...

  13. HOW TO SELECT APPROPRIATE HUMAN RESOURCE CONTROLLING INDICATORS

    OpenAIRE

    Monika Dugelova; Mariana Strenitzerova

    2015-01-01

    Human resource controlling represents a company’s strategic method to support its role is planning, checking, and managing—including information supplement for human resources department. Human resource controlling helps with optimization and transformation of human resource functions and with general human resource management. Our survey deals with the implementation of human resource controlling in information technology companies. The selection of appropriate human resource controlling too...

  14. Function of controlled release fertilizer in maintaining high agronomic use efficiency and minimizing environmental pollution in rice field of southern China

    Institute of Scientific and Technical Information of China (English)

    Ji Xionghui; Luo Lanfang; Zheng Shengxian

    2006-01-01

    Development and use of controlled release fertilizer (CRF) in southern China, potential advantages of CRF in increasing rice yield and nutrient use efficiency were introduced, as well as its role of minimizing rice field's environmental contamination was discussed. Meanwhile, some suggestions were proposed.

  15. Use of CT imaging to examine the coarse roots, rhizomes, and peat associated with creek bank Spartina alterniflora in fertilized and control creeks in Plum Island (MA)

    Science.gov (United States)

    We used computer-aided tomography (CT) to quantify the wet mass, abundance, and diameter of coarse roots and rhizomes as well as the wet mass and particle density of marsh peat in 7-year fertilized and control creeks in Plum Island (MA). In shallow soils (0 – 10 cm) and at dep...

  16. Pregnancy rates with recombinant versus urinary human chorionic gonadotropin in in vitro fertilization: an observational study.

    Science.gov (United States)

    Zeke, József; Kanyó, Katalin; Zeke, Helga; Cseh, Aron; Vásárhelyi, Barna; Szilágyi, András; Konc, János

    2011-01-01

    Randomized clinical trials (RCTs) demonstrated the equal efficacy of urinary human chorionic gonadotropin (uhCG) and recombinant hCG (rhCG) products in in vitro fertilisation (IVF). However, limitations inherent with RCTs necessitate the reinforcement of RCT results in real-life. We retrospectively analyzed pregnancies after treatment with rhCG and uhCG products (n = 391, and 96, resp.). We found that laboratory-verified pregnancy occurred more frequently in rhCG patients than in those on uhCG (43% versus 30%, P = 0.02). The association remains significant (P = 0.002) after its adjustment for clinical characteristics. The prevalence of laboratory-verified pregnancies was higher with GnRH agonist use (P = 0.012) and BMI under 30 kg/m(2) (P = 0.053) while decreased the age (P = 0.014) and the number of previous failed attempts (P = 0.08). Similar (but not significant) trends were observed with rates of pregnancy filled the 24th week. These results reinforce RCTs supporting the notion that rhCG is more efficient as uhCG during IVF.

  17. Effects of a controlled-release fertilizer on yield, nutrient uptake, and fertilizer usage efficiency in early ripening rapeseed (Brassica napus L.)

    Institute of Scientific and Technical Information of China (English)

    Chang TIAN; Xuan ZHOU; Qiang LIU; Jian-wei PENG; Wen-ming WANG; Zhen-hua ZHANG; Yong YANG; Hai-xing SONG; Chun-yun GUAN

    2016-01-01

    中文概要题目:控释肥料对早熟油菜产量、养分吸收和肥料利用率的影响目的:氮(N)、磷(P)和钾(K)是作物生长发育所必需的营养元素。然而,过度地投入会导致田间低效的利用率,造成大量养分损失,影响土壤、水和大气的质量,以及人类健康和生物多样性。因此,本实验研究控释肥料(CRF)是否可以替代可溶性肥料(SF),有效地增加作物产量,提高肥料利用率,减少田间养分损失。创新点:连续2年(2011~2013年)在中国南方红黄壤地区开展田间试验,研究控释肥料对早熟油菜(湘杂油1613)的产量、生长、养分吸收和肥料利用率的影响。可更好地解决稻‒稻‒油生产过程中的季节矛盾,简化油菜生产模式,增加农民收入,并确保国家粮油安全。方法:设置SF和等量CRF五个施用量处理,即SF1/CRF1(3750 kg/hm2)、SF2/CRF2(3000 kg/hm2)、SF3/ CRF3(2250 kg/hm2)、SF4/CRF4(1500 kg/hm2)和SF5/CRF5(750 kg/hm2),以及不施肥处理(CK)。结论:CRF 处理油菜产量较 SF 处理两年平均提高14.51%,其中 CRF4和 SF3处理获得最大产量(2066.97和1844.50 kg/hm2),其次是CRF3处理(1929.97 kg/hm2)和SF4处理(1839.40 kg/hm2)。此外,CRF4处理利润最高(人民币7126.4元每公顷),与SF4处理相比,其油菜产量增加12.37%和单位肥料施用量下降11.01%。较SF处理,CRF处理显著增加油菜分支数、角果数和干物质重量(P0.05). CRF4 had the highest profit (7126.4 CNY/hm2) and showed an increase of 12.37% in seed yield, and it decreased by 11.01% in unit fertilizer rate compared with SF4. The branch number, pod number, and dry matter weight compared with SF increased significantly under the fertilization of CRF (P<0.05). The pod number per plant was the major contributor to seed yield. On the other hand, the N, P, and K up-takes increased at first and

  18. Human reliability analysis of control room operators

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Isaac J.A.L.; Carvalho, Paulo Victor R.; Grecco, Claudio H.S. [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil)

    2005-07-01

    Human reliability is the probability that a person correctly performs some system required action in a required time period and performs no extraneous action that can degrade the system Human reliability analysis (HRA) is the analysis, prediction and evaluation of work-oriented human performance using some indices as human error likelihood and probability of task accomplishment. Significant progress has been made in the HRA field during the last years, mainly in nuclear area. Some first-generation HRA methods were developed, as THERP (Technique for human error rate prediction). Now, an array of called second-generation methods are emerging as alternatives, for instance ATHEANA (A Technique for human event analysis). The ergonomics approach has as tool the ergonomic work analysis. It focus on the study of operator's activities in physical and mental form, considering at the same time the observed characteristics of operator and the elements of the work environment as they are presented to and perceived by the operators. The aim of this paper is to propose a methodology to analyze the human reliability of the operators of industrial plant control room, using a framework that includes the approach used by ATHEANA, THERP and the work ergonomics analysis. (author)

  19. Field Test of Controlled-release BB Fertilizer Applied in Sugarcane%甘蔗控释BB肥田间肥效试验初报

    Institute of Scientific and Technical Information of China (English)

    容小阳; 丁春华; 贾应明; 李言春

    2011-01-01

    Controlled-release BB Fertilizer for sugarcane is a special formula fertilizer using patented technology according to soil nutrient content and the requirements of sugarcane growth. It can provide successive nutrients to crops according to the growth stage of the crop. Application of Controlled-release BB Fertilizer can considerably improve fertilizer utilization, prevent fertilizer waste, and reduce pollution to the environment. It can increase crop yield and improve crop quality without imposing harmful effect to the soil, water and atmosphere. The once-for-all fertilization process can also reduce manpower requirements.%甘蔗控释BB肥是根据土壤中养分含量水平,按照甘蔗对养分的需求规律,采用专利技术研制而成。该肥料根据作物生长各时期对肥料的需求持续提供养分。使用控释BB肥可以明显提高肥料的利用率,有效避免肥料的流失浪费,大幅降低化肥对环境的污染,既保护了土壤、水体、空气环境,又提高了作物的产量和质量。同时,采用一次性施肥方法还节约了劳动力和成本,效果十分明显。

  20. [Nitrogen uptake rate and use efficiency by rice under different levels of the controlled-release N fertilizers (CRF) in the Nansi Lake basin].

    Science.gov (United States)

    Zhang, Qing-Wen; Du, Chun-Xiang; Li, Xiao-Wei; Li, Gui-Chun; Wang, Ming

    2011-07-01

    The nitrogen (N) fertilizers overused or misused are the main contributors for water eutrophication of the Nansi Lake in eastern China. A field experiment with different application levels of controlled-release N fertilizer (CRF) was carried out at a rice field in the Nansi lake basin to provide information on the nitrogen uptake rate and use efficiency by rice with CRF application at different growth stages of rice. The fertilization levels for the controlled fertilizer in this study were 0, 300, 337.5 and 375 kg/hm2, respectively, and 375 kg/hm2 for conventional urea (CU). We estimated the N uptake rate in different growing season and apparent recovery of fertilizer in root, stover and grain of rice. The result showed that grain yield increased by higher N rate. However, the N uptake rate did not increase linearly with the nitrogen application amount. The highest N uptake rate was 22.48 mg/(plant x d) under the fertilization amount of 337.5 kg/hm2 during the young panicle differentiation stage. Apparent N recovery efficiency for CU with traditional application amount of 375 kg/hm2 was 21.86%. Apparent N recovery efficiency for CRF with application amount of 337.5 kg/hm2 was highest with 37.17%. Based on the statistical data, with CU of traditional urea application amount of 375 kg/hm2, nitrogen loss and soil N residue at one growing season are 130.07 x 10(3) t for Jining city and 11.4 x 10(3) t for Yutai county of the Nansi Lake basin. If using CRF with the optimized application amount of 337.5 kg/hm2, nitrogen loss and soil residual at one growing season is 10.46 x 10(4) t for Jining city. It could reduce losses of 2.55 x 10(4) t N for Jining city and 2 235.26 t N for Yutai county per year. Because of releasing patterns more closely matched to crop N uptake patterns, controlled release N fertilizer could be a good way to prevent water eutrophication due to nitrogen fertilizer overused or misused in the Nansi Lake.

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

    Science.gov (United States)

    Shaviv, Avi; Raban, Smadar; Zaidel, Elina

    2003-05-15

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

  2. Use of medroxyprogesterone acetate in women with ovarian endometriosis undergoing controlled ovarian hyperstimulation for in vitro fertilization.

    Science.gov (United States)

    Guo, Haiyan; Wang, Yun; Chen, Qiuju; Chai, Weiran; Sun, Lihua; Ai, Ai; Fu, Yonglun; Lyu, Qifeng; Kuang, Yanping

    2017-09-20

    This study investigated the use of medroxyprogesterone acetate (MPA) or a short protocol for controlled ovarian hyperstimulation (COH) in patients with advanced endometriosis who have normal ovarian function, and to compare cycle characteristics and pregnancy outcomes after frozen-thawed embryo transfer (FET). This was a retrospective case-control study of 244 patients with advanced endometriosis undering COH. The patients were allocated to three groups: the surgery group with MPA COH (62 patients, 71 IVF/ICSI cycles, 78 FET cycles); the aspiration group with MPA COH (85 patients had ovarian "chocolate" cysts (>3 cm) aspirated, 90 IVF/ICSI cycles, 76 FET cycles); and the short protocol group (97 patients, 101 IVF/ICSI cycles, 51 FET cycles). The results showed that higher rates of mature oocyte, D3 high quality embryo, hMG dose were observed in the two study groups using MPA compared with the short protocol. The number of >10-14 mm follicles on the trigger day, D3 top-quality embryos, viable embryos, rates of cancellation, fertilization, implantation, pregnancy outcomes were similar among the three groups. The oocytes, embryos, and pregnancy outcomes were not influenced by endometrioma surgery or presence of endometrioma. MPA COH could be effective for women with ovarian advanced endometriosis who had normal ovarian function.

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

    Directory of Open Access Journals (Sweden)

    Nicole Willers

    2015-12-01

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

  4. Have humans lost control: The elusive X-controlling element.

    Science.gov (United States)

    Peeters, Samantha B; Yang, Christine; Brown, Carolyn J

    2016-08-01

    The process of X-chromosome inactivation (XCI) randomly silences one of two X chromosomes in normal female cells. The ability to predict if there is a preference for one of the two Xs to be chosen (and survive) more often as the active X has important repercussions in human health and X-linked disease. Mice have a genetic component that modulates non-random skewing called the X-controlling element (Xce). Although the nature of the locus and its mechanisms of action are still under investigation, it is clear that different mouse strains carry unique Xce alleles on their X chromosomes, resulting in distinct skewing phenotypes in the F1 progeny of hybrid crosses. Whether a similar mechanism exists in humans is unclear, and challenges to identifying such a locus include the complexity and diversity of the human genome, the restricted time points and tissue(s) of examination in human subjects, and the lack of a model system recapitulating XCI in early development. In this review we consider the evidence for such a controlling locus in humans, in addition to discussing if we have the power to recognize it given the contribution of selective growth in causing skewed patterns of XCI.

  5. The ESEP study: Salpingostomy versus salpingectomy for tubal ectopic pregnancy; The impact on future fertility: A randomised controlled trial

    Directory of Open Access Journals (Sweden)

    van Mello Norah M

    2008-06-01

    Full Text Available Abstract Background For most tubal ectopic pregnancies (EP surgery is the treatment of first choice. Whether surgical treatment should be performed conservatively (salpingostomy or radically (salpingectomy in women wishing to preserve their reproductive capacity, is subject to debate. Salpingostomy preserves the tube, but bears the risks of both persistent trophoblast and repeat ipsilateral tubal EP. Salpingectomy, avoids these risks, but leaves only one tube for reproductive capacity. This study aims to reveal the trade-off between both surgical options: whether the potential advantage of salpingostomy, i.e. a better fertility prognosis as compared to salpingectomy, outweighs the potential disadvantages, i.e. persistent trophoblast and an increased risk for a repeat EP. Methods/Design International multi centre randomised controlled trial comparing salpingostomy versus salpingectomy in women with a tubal EP without contra lateral tubal pathology. Hemodynamically stable women with a presumptive diagnosis of tubal EP, scheduled for surgery, are eligible for inclusion. Patients pregnant after in vitro fertilisation (IVF and/or known documented tubal pathology are excluded. At surgery, a tubal EP must be confirmed. Only women with a tubal EP amenable to both interventions and a healthy contra lateral tube are included. Salpingostomy and salpingectomy are performed according to standard procedures of participating hospitals. Up to 36 months after surgery, women will be contacted to assess their fertility status at six months intervals starting form the day of the operation. The primary outcome measure is the occurrence of spontaneous viable intra uterine pregnancy. Secondary outcome measures are persistent trophoblast, repeat EP, all pregnancies including those resulting from IVF and financial costs. The analysis will be performed according to the intention to treat principle. A cost-effectiveness analysis will be performed within a decision

  6. N-glycoproteomic analysis of human follicular fluid during natural and stimulated cycles in patients undergoing in vitro fertilization.

    Science.gov (United States)

    Lim, Hee-Joung; Seok, Ae Eun; Han, Jiyou; Lee, Jiyeong; Lee, Sungeun; Kang, Hee-Gyoo; Cha, Byung Heun; Yang, Yunseok

    2017-06-01

    Hyperstimulation methods are broadly used for in vitro fertilization (IVF) in patients with infertility; however, the side effects associated with these therapies, such as ovarian hyperstimulation syndrome (OHSS), have not been well studied. N-glycoproteomes are subproteomes used for the remote sensing of ovarian stimulation in follicular growth. Glycoproteomic variation in human follicular fluid (hFF) has not been evaluated. In this study, we aimed to identify and quantify the glycoproteomes and N-glycoproteins (N-GPs) in natural and stimulated hFF using label-free nano-liquid chromatography/electrospray ionization-quad time-of-flight mass spectrometry. For profiling of the total proteome and glycoproteome, pooled protein samples from natural and stimulated hFF samples were selectively isolated using hydrazide chemistry to obtain the total proteomes and glycoproteomes. N-GPs were validated by the consensus sequence N-X-S/T (92.2% specificity for the N-glycomotif at p<0.05). All data were compared between natural versus hyperstimulated hFF samples. We detected 41 and 44 N-GPs in the natural and stimulated hFF samples, respectively. Importantly, we identified 11 N-GPs with greater than two-fold upregulation in stimulated hFF samples compared to natural hFF samples. We also validated the novel N-GPs thyroxine-binding globulin, vitamin D-binding protein, and complement proteins C3 and C9. We identified and classified N-GPs in hFF to improve our understanding of follicular physiology in patients requiring assisted reproduction. Our results provided important insights into the prevention of hyperstimulation side effects, such as OHSS.

  7. Vitamin D and female fertility.

    Science.gov (United States)

    Lerchbaum, Elisabeth; Rabe, Thomas

    2014-06-01

    Apart from the well known effects of vitamin D on maintaining calcium homeostasis and promoting bone mineralization, there is some evidence suggesting that vitamin D also modulates human reproductive processes. We will review the most interesting and relevant studies on vitamin D and female fertility published over the past year. In the past year, several observational studies reported a better in-vitro fertilization outcome in women with sufficient vitamin D levels (≥30 ng/ml), which was mainly attributed to vitamin D effects on the endometrium. One randomized controlled trial found an increased endometrial thickness in women with polycystic ovary syndrome (PCOS) receiving vitamin D during intrauterine insemination cycles. Further, vitamin D supplementation had a beneficial effect on serum lipids in PCOS women. Vitamin D treatment improved endometriosis in a rat model and increased vitamin D intake was related to a decreased risk of incident endometriosis. Vitamin D was also favorably associated with primary dysmenorrhea, uterine leiomyoma, and ovarian reserve in late reproductive aged women. In women undergoing in-vitro fertilization, a sufficient vitamin D level (≥30 ng/ml) should be obtained. Vitamin D supplementation might improve metabolic parameters in women with PCOS. A high vitamin D intake might be protective against endometriosis.

  8. 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

  9. Present Situation, Existing Problems of Controlled Release Fertilizer Research and Countermeasures%控释肥料研究现状、存在问题及对策①

    Institute of Scientific and Technical Information of China (English)

    刘海林; 林钊沐; 罗微; 华元刚; 郑国亮; 王龙宇

    2014-01-01

    综述控释肥料的定义及与缓释肥料的区别,分析控释肥料包膜材料、包膜工艺研究现状,指出控释肥料研究和产业化中存在的问题,提出对策,并对今后控释肥料研究发展进行展望。%On the base of research data about controlled release fertilizer, in this paper we expounded the definition of controlled release fertilizer, explained the difference between controlled release fertilizer and slow release fertilizer. We also analyzed the present situation on coated materials, coating technique, discussed the existing problems on research and industrialization of controlled release fertilizer, and puts forward strategy according to the problem. The last, we prospected the research and development in the future.

  10. Comparative Test of Different Dosages of Controlled-released Fertilizer on Winter Potato%冬季马铃薯控释肥用量试验

    Institute of Scientific and Technical Information of China (English)

    王云梅; 黄修芬; 罗晓玲; 付立会; 杨颉; 彭明强

    2016-01-01

    在川西南冬季马铃薯种植区,开展马铃薯专用控释配方肥不同用量对青薯9号增产效应的对比试验。试验结果表明,以每667 m2施用60 kg马铃薯专用控释配方肥作底肥为最佳施肥方案,该处理的平均单株质量、商品薯率最高,平均鲜薯产量为2114.0 kg/667 m2,比对照(不施肥)增产1063.5 kg/667 m2,增幅为101.2%。%We carried out the comparative test to study the effects of different dosages of controlled-released fertilizer specially used for potato on yield increasing of Qingshu No.9 in winter potato planting area of southwest Sichuan . The results showed that, the best fertilization scheme was applying 60 kg/667 m2 controlled-released fertilizer specially used for potato as base fertilizer. The treatment had the heaviest average single plant weight and highest marketable tuber rate, and the fresh tuber yield was 2 114.0 kg/667 m2, which was increased by 1 063.5 kg/667 m2 compared to the control treatment (no fertilizer application), with the yield increasing rate of 101.2%.

  11. Stressor controllability modulates fear extinction in humans.

    Science.gov (United States)

    Hartley, Catherine A; Gorun, Alyson; Reddan, Marianne C; Ramirez, Franchesca; Phelps, Elizabeth A

    2014-09-01

    Traumatic events are proposed to play a role in the development of anxiety disorders, however not all individuals exposed to extreme stress experience a pathological increase in fear. Recent studies in animal models suggest that the degree to which one is able to control an aversive experience is a critical factor determining its behavioral consequences. In this study, we examined whether stressor controllability modulates subsequent conditioned fear expression in humans. Participants were randomly assigned to an escapable stressor condition, a yoked inescapable stressor condition, or a control condition involving no stress exposure. One week later, all participants underwent fear conditioning, fear extinction, and a test of extinction retrieval the following day. Participants exposed to inescapable stress showed impaired fear extinction learning and increased fear expression the following day. In contrast, escapable stress improved fear extinction and prevented the spontaneous recovery of fear. Consistent with the bidirectional controllability effects previously reported in animal models, these results suggest that one's degree of control over aversive experiences may be an important factor influencing the development of psychological resilience or vulnerability in humans.

  12. Study on the Rapid Method to Predict Longevity of Controlled Release Fertilizer Coated by Water Soluble Resin

    Institute of Scientific and Technical Information of China (English)

    DAI Jian-jun; FAN Xiao-lin; YU Jian-gang; LIU Fang; ZHANG Qiao

    2008-01-01

    The study discussed the rapid method to test and predict the longevity of controlled release fertilizers (CRFs) coated by water soluble resin by using the short-term leaching under higher temperature.Pure water dissolving incubation and higher temperature leaching were used to study the patterns of the nutrient release of the CRFs.The correlation analysis between the days at 25℃ and the hours at 80℃ of Trincote 1 and Trincote 2 for the same cumulative release rates were conducted.Patterns of cumulative nutrient release curve followed one factor quadratic regression equation at each given temperatures,and each of relative coefficient was bigger than 0.995.As the temperature increased,nutrients release of the CRFs increased.The longevity of resin coated CRFs were predicted by use of both the cumulative nutrients release equation at 80℃ and the regression equation of release time needed for the same cumulative release rates between 25 and 80℃.There were only 0.3-6.9% relative errors between the tested longevity and predicted one.In conclusion,the longevity of resin coated CRFs could be predicted more quickly and precisely by use of the higher temperature short-term leaching method than that of the traditional differential release rate.The longevity of resin coated CRF could be rapidly and precisely predicted in a few hours by application of the higher temperature shortterm leaching method.

  13. 控释配方肥中不同控释养分比例对香蕉产量的影响%Effect of the ratio of controlled release nutrients in blending controlled release fertilizers on yield of banana

    Institute of Scientific and Technical Information of China (English)

    刘延涛; 樊小林; 王南南; 刘庆虎

    2011-01-01

    【Objective】 The regression equation of blending controlled release fertilizer for banana was established to determine the optimal percentage of controlled-N,-P and-K in the total nutrient amounts,and thus to provide an efficient-convenient fertilizer source and fertilization technology for banana production.【Method】 Ternary quadratic regression design and field trials were used to study the effect of ratio of controlled nitrogen,phosphorus and potassium in blending controlled-release fertilizers(BCRF) on yield of banana to determine the rational formula of the BCRF,compared with no fertilizer and conventional fertilizer.【Result】 Compared with total water soluble compound fertilizers,high N and K contained blending controlled release fertilizers(T3 treatment),that is,the fertilizer contained 46.5% controlled-N,3.5% controlled-P and 18.2% controlled-K over the total N,P or K.The production of the T3 was 30.44 kg/plant and the yield increased by 22.65%.Of the compound fertilizers,the ratio of controlled-N and-K significantly affected the banana yield whereas the ratio of controlled-P didn’t.Blending controlled release N and K fertilizer cooperated with water soluble fertilizers could prevent the N and K deficiency during the latter stage of banana growth compared with the treatment with only water soluble compound fertilizers.Application of controlled release blending fertilizer(BCRF) could enhance yields significantly.【Conclusion】 Controlled-N and controlled-K had great impact on banana yield,despite the little effect of controlled-P.The controlled-N,controlled-P and controlled-K content for the optimal yield were 33.6%,0% and 11.0% over the total N,P and K in the BCRF espectively.%【目的】建立香蕉系列控释配方肥的产量效应方程,确定适于香蕉生长发育的控释氮、磷、钾比例,为香蕉产业提供高效、简便的肥料和施肥技术。【方法】采用大田试验及三元二次回归设计,以不

  14. Occupational risk for male infertility: a case-control study of 218 infertile and 227 fertile men.

    Science.gov (United States)

    Chia, S E; Tay, S K

    2001-11-01

    The aim of the study was to determine if certain occupations pose an increased risk for infertility (of no known cause) among a group of infertile men compared with a group of fertile men. A total of 640 consecutive men whose spouses were unable to conceive were recruited from an infertility clinic. Of these, 218 men (cases) were found to have no known cause for their infertility. A total of 227 men whose spouses were pregnant at the time of the study were recruited as controls. The Singapore Standard Occupational Classification was used to code the subjects' occupations. Semen parameters (density, total sperm counts, motility, viability, and normal morphology) in all of the cases were significantly poorer than those in the controls. The risk for infertility is associated with smoking adjusted odds ratio (OR) 2.85 and 95% confidence interval (CI) 1.91 to 4.24. Work, independently, is not a risk factor for infertility. Engineering technicians (adjusted OR, 2.75; 95% CI, 1.36 to 5.54), finance analysts (adjusted OR, 4.66; 95% CI, 1.90 to 11.40), corporate and computing managers (adjusted OR, 2.49; 95% CI, 1.04 to 5.98), and teachers (adjusted OR, 7.72; 95% CI, 1.86 to 32.10) were at a greater risk of infertility compared with "services and clerical workers." Using services and clerical workers as a reference group, certain occupations are at a higher risk for infertility. Higher work demands and possible electromagnetic field exposure could be contributory factors for infertility.

  15. Effects of Phaseolus vulgaris QTL in controlling host-bacteria interactions under two levels of nitrogen fertilization

    Directory of Open Access Journals (Sweden)

    Souza Alessandra A.

    2000-01-01

    Full Text Available Molecular markers were used to estimate the effect of mineral nitrogen on the phenotypic expression of quantitative trait loci (QTL controlling the number of Rhizobium nodules (NN and resistance to Xanthomonas axonopodis pv. phaseoli in the common bean. Recombinant inbred lines derived from a BAT-93 x Jalo EEP558 cross were grown in a greenhouse in the absence or presence (5 mM NH4NO3 of nitrogen. Resistance to Xanthomonas was assessed as diseased leaf area (DLA and the number of nodules was obtained by direct counting. Analyses of variance were used to detect significant associations between 85 marker loci from 12 linkage groups (LG and quantitative traits. In the absence of nitrogen, 15 and 11 markers, distributed over 7 and 5 LG, showed a significant association with NN and DLA, respectively. The combined percentage of phenotypic variance explained by the marker-loci and QTL associations was 34% for NN and 42% for DLA. In the presence of nitrogen, there were only five significant associations for NN and eight for DLA, which explained 28 and 26% of the total phenotypic variance, respectively. The effects of some QTL were detected only at a certain level of nitrogen. The contribution of parental alleles at two NN QTL was dependent on the level of nitrogen. Four QTL were associated with both the number of Rhizobium nodules and resistance to Xanthomonas, suggesting a common genetic control of responses to bacterial infections in the common bean. Despite the dramatic environmental interactions noted with some QTL, in other cases the phenotypic effects were not affected by the amount of nitrogen. The stability of the latter QTL may be relevant when breeding cultivars adapted to variable soil fertility.

  16. Statistical correlation of the soil incubation and the accelerated laboratory extraction methods to estimate nitrogen release rates of slow- and controlled-release fertilizers.

    Science.gov (United States)

    Medina, L Carolina; Sartain, Jerry; Obreza, Thomas; Hall, William L; Thiex, Nancy J

    2014-01-01

    Several technologies have been proposed to characterize the nutrient release patterns of enhanced-efficiency fertilizers (EEFs) during the last few decades. These technologies have been developed mainly by manufacturers and are product-specific based on the regulation and analysis of each EEF product. Despite previous efforts to characterize nutrient release of slow-release fertilizer (SRF) and controlled-release fertilizer (CRF) materials, no official method exists to assess their nutrient release patterns. However, the increased production and distribution of EEFs in specialty and nonspecialty markets requires an appropriate method to verify nutrient claims and material performance. Nonlinear regression was used to establish a correlation between the data generated from a 180-day soil incubation-column leaching procedure and 74 h accelerated lab extraction method, and to develop a model that can predict the 180-day nitrogen (N) release curve for a specific SRF and CRF product based on the data from the accelerated laboratory extraction method. Based on the R2 > 0.90 obtained for most materials, results indicated that the data generated from the 74 h accelerated lab extraction method could be used to predict N release from the selected materials during 180 days, including those fertilizers that require biological activity for N release.

  17. Optimization and validation of an accelerated laboratory extraction method to estimate nitrogen release patterns of slow- and controlled-release fertilizers.

    Science.gov (United States)

    Medina, L Carolina; Sartain, Jerry B; Obreza, Thomas A; Hall, William L; Thiex, Nancy J

    2014-01-01

    Several technologies have been proposed to characterize the nutrient release and availability patterns of enhanced-efficiency fertilizers (EEFs), especially slow-release fertilizers (SRFs) and controlled-release fertilizers (CRFs) during the last few decades. These technologies have been developed mainly by manufacturers and are product-specific based on the regulation and analysis of each EEF product. Despite previous efforts to characterize EEF materials, no validated method exists to assess their nutrient release patterns. However, the increased use of EEFs in specialty and nonspecialty markets requires an appropriate method to verify nutrient claims and material performance. A series of experiments were conducted to evaluate the effect of temperature, fertilizer test portion size, and extraction time on the performance of a 74 h accelerated laboratory extraction method to measure SRF and CRF nutrient release profiles. Temperature was the only factor that influenced nutrient release rate, with a highly marked effect for phosphorus and to a lesser extent for nitrogen (N) and potassium. Based on the results, the optimal extraction temperature set was: Extraction No. 1-2:00 h at 25 degrees C; Extraction No. 2-2:00 h at 50 degrees C; Extraction No. 3-20:00 h at 55 degrees C; and Extraction No. 4-50:00 h at 60 degrees C. Ruggedness of the method was tested by evaluating the effect of small changes in seven selected factors on method behavior using a fractional multifactorial design. Overall, the method showed ruggedness for measuring N release rates of coated CRFs.

  18. Voluntary control of human jaw stiffness.

    Science.gov (United States)

    Shiller, Douglas M; Houle, Guillaume; Ostry, David J

    2005-09-01

    Recent studies of human arm movement have suggested that the control of stiffness may be important both for maintaining stability and for achieving differences in movement accuracy. In the present study, we have examined the voluntary control of postural stiffness in 3D in the human jaw. The goal is to address the possible role of stiffness control in both stabilizing the jaw and in achieving the differential precision requirements of speech sounds. We previously showed that patterns of kinematic variability in speech are systematically related to the stiffness of the jaw. If the nervous system uses stiffness control as a means to regulate kinematic variation in speech, it should also be possible to show that subjects can voluntarily modify jaw stiffness. Using a robotic device, a series of force pulses was applied to the jaw to elicit changes in stiffness to resist displacement. Three orthogonal directions and three magnitudes of forces were tested. In all conditions, subjects increased the magnitude of jaw stiffness to resist the effects of the applied forces. Apart from the horizontal direction, greater increases in stiffness were observed when larger forces were applied. Moreover, subjects differentially increased jaw stiffness along a vertical axis to counteract disturbances in this direction. The observed changes in the magnitude of stiffness in different directions suggest an ability to control the pattern of stiffness of the jaw. The results are interpreted as evidence that jaw stiffness can be adjusted voluntarily, and thus may play a role in stabilizing the jaw and in controlling movement variation in the orofacial system.

  19. Control and surveillance of human African trypanosomiasis.

    Science.gov (United States)

    2013-01-01

    In the 1960s, it appeared that human African trypanosomiasis (HAT) could be effectively controlled, but by the beginning of the twenty-first century several decades of neglect had led to alarming numbers of reported new cases, with an estimated 300 000 people infected. The World Health Organization (WHO) responded with a series of initiatives aimed at bringing HAT under control again. Since 2001, the pharmaceutical companies that produce drugs for HAT have committed themselves to providing them free of charge to WHO for distribution for the treatment of patients. In addition, funds have been provided to WHO to support national sleeping sickness control programmes to boost control and surveillance of the disease. That, coupled with bilateral cooperation and the work of nongovernmental organizations, helped reverse the upward trend in HAT prevalence. By 2012, the number of reported cases was fewer than 8000. This success in bringing HAT under control led to its inclusion in the WHO Roadmap for eradication, elimination and control of neglected tropical diseases, with a target set to eliminate the disease as a public health problem by 2020. A further target has been set, by countries in which HAT is endemic, to eliminate gambiense HAT by reducing the incidence of infection to zero in a defined geographical area. This report provides information about new diagnostic approaches, new therapeutic regimens and better understanding of the distribution of the disease with high-quality mapping. The roles of human and animal reservoirs and the tsetse fly vectors that transmit the parasites are emphasized. The new information has formed the basis for an integrated strategy with which it is hoped that elimination of gambiense HAT will be achieved. The report also contains recommendations on the approaches that will lead to elimination of the disease.

  20. Rational design of an orthogonal noncovalent interaction system at the MUPP1 PDZ11 complex interface with CaMKIIα-derived peptides in human fertilization.

    Science.gov (United States)

    Zhang, Yi-Le; Han, Zhao-Feng

    2017-08-23

    The recognition and association between the Ca(2+)/calmodulin-activated protein kinase II-α (CaMKIIα) and the multi-PDZ domain protein 1 (MUPP1) plays an important role in the sperm acrosome reaction and human fertilization. Previously, we have demonstrated that the MUPP1 PDZ11 domain is the primary binding partner of the CaMKIIα C-terminal tail, which can be targeted by a rationally designed sia peptide with nanomolar affinity. Here, we further introduced an orthogonal noncovalent interaction (ONI) system between a native hydrogen bond and a designed halogen bond across the complex interface of the PDZ11 domain with the sia [Asn-1Phe] peptide mutant, where the halogen bond was formed by substituting the o-hydrogen atom of the benzene ring of the peptide Phe-1 residue with a halogen atom (F, Cl, Br or I). Molecular dynamics simulations and high-level theoretical calculations suggested that bromine (Br) is a good compromise between the halogen-bonding strength and steric hindrance effect due to introduction of a bulkier halogen atom into the tightly packed complex interface. Fluorescence spectroscopy assays revealed that the resulting o-Br-substituted peptide (Kd = 18 nM) exhibited an ∼7.6-fold affinity increase relative to its native counterpart (Kd = 137 nM). In contrast, the p-Br-substituted peptide, a negative control that is unable to establish the ONI according to structure-based analysis, has decreased affinity (Kd = 210 nM) upon halogenation.

  1. Female Fertility: Is it Safe to "Freeze?"

    Institute of Scientific and Technical Information of China (English)

    Lu Zhang; Li-Ying Yan; Xu Zhi; Jie Yan; Jie Qiao

    2015-01-01

    Objective:To evaluate the safety and risk of cryopreservation in female fertility preservation.Data sources:The data analyzed in this review were the English articles from 1980 to 2013 from journal databases,primarily PubMed and Google scholar.The criteria used in the literature search show as following:(1) human; embryo; cryopreservation/freezing/vitrification,(2) human; oocyte/immature oocyte; cryopreservation/freezing/vitrification,(3) human; ovarian tissue transplantation; cryopreservation/ freezing/vitrification,(4) human; aneuploidy/DNA damage/epigenetic; cryopreservation/freezing/vitrification,and (5) human; fertility preservation; maternal age.Study selection:The risk ratios based on survival rate,maturation rate,fertilization rate,cleavage rate,implantation rate,pregnancy rate,and clinical risk rate were acquired from relevant meta-analysis studies.These studies included randomized controlled trials or studies with one of the primary outcome measures covering cryopreservation of human mature oocytes,embryos,and ovarian tissues within the last 7 years (from 2006 to 2013,since the pregnancy rates of oocyte vitrification were significantly increased due to the improved techniques).The data involving immature oocyte cryopreservation obtained from individual studies was also reviewed by the authors.Results:Vitrifications of mature oocytes and embryos obtained better clinical outcomes and did not increase the risks of DNA damage,spindle configuration,embryonic aneuploidy,and genomic imprinting as compared with fresh and slow-freezing procedures,respectively.Conclusions:Both embryo and oocyte vitrifications are safe applications in female fertility preservation.

  2. 载体型控释肥料在玉米上的应用效果%Effects of Supported Controlled Release Fertilizers on Maize

    Institute of Scientific and Technical Information of China (English)

    郑秀琴; 丁洪; 张玉树; 何新桃; 洪曾纯

    2011-01-01

    研究了栽体型控释肥料在玉米上的应用效果.结果表明,在等养分比例和等养分量处理下,控释肥料处理的经济产量比普通肥料混合后一次性施用处理增加14.9% ~17.0%,总生物量增加11.3%~14.5%,氮、磷、钾当季利用率分别提高8.2%~11.2%、4.0% ~4.6%和2.7% ~ 5.5%.与普通肥料混合后分2次施用处理相比,经济产量增加10.9% ~ 13.0%,总生物量增加9.8%~13.0%,氮、磷、钾当季利用率分别提高5.8% ~8.8%、2.1% ~2.7%和7.6% ~10.4%.此外,控释肥料还可以改善玉米的品质,子粒的粗脂肪和粗蛋白含量都有所提高.%Effects of supported controlled release fertilizers on maize were studied. The results showed that the controlled release fertilizers could increase economic yield of maize by 14. 9% - 17.0% ,biological yield by 11. 3% -14. 5% ,and improved nitrogen,phosphorus and potassium use efficiency by 8. 2% - 11. 2% ,4. 0% -4. 6% and 2.7% -5. 5% , respectively compared with common fertilizers used at one time under the conditions of all treatments with same NPK proportion and amount. To compare with common fertilizers used at two times, the controlled release fertilizers increased economic yield of maize by 10. 9% -13. 0% ,biological yield by 9. 8% -13.0% ,and improved nitrogen, phosphorus and potassium use efficiency by 5. 8% - 8. 8% ,2. 1% - 2. 7% and 7. 6% -10. 4% , respectively. In addition,the controlled release fertilizers also influenced the quality of maize since the contents of protein and fat in grains were improved more or less.

  3. Effects of organic and chemical fertilizer on plant nutritional status and soil fertility of tomatoes grown under greenhouse condition

    Directory of Open Access Journals (Sweden)

    Elif Işıl DEMİRTAŞ

    2012-06-01

    Full Text Available The effect of some plant originated liquid organic fertilizer on soil fertility and plant nutritional status of tomato plants were investigated. The experiment was planned to compare the control, organic fertilizer, chemical fertilizer, 1/1chemical+organic fertilizer, ½chemical+organic fertilizer, chemical fertilizer+foliar organic fertilizer application. The trial was conducted in randomised complete block design with four replications. Plant and soil samples were analyzed. According to the results of analysis, combinations of organic and chemical fertilizer generally gave more positive results.

  4. Development Status and Research Trends of Slow/Controlled Release Fertilizer%我国缓/控释肥研究现状和发展趋势

    Institute of Scientific and Technical Information of China (English)

    王恩飞; 崔智多; 何璐; 肖传绪; 莫海涛; 张小勇

    2011-01-01

    从养分控释的途径对缓/控释肥进行分类,介绍代表产品,总结我国当前研究情况,并对研究趋势进行展望.%Slow/controlled release fertilizer was classified by the means of the nutrient release. The representative products were introduced.The current research situation in China were summarized. And the research trends were discussed.

  5. 缓/控释肥料的研究现状及发展趋势%Researching Present Situation and Developing Trend for Releasing Fertilizer Slowly/Controlled

    Institute of Scientific and Technical Information of China (English)

    刘英; 熊海蓉; 李霞; 熊远福; 文祝友; 王楠楠

    2012-01-01

    Author has introduced the definition and type of releasing fertilizer slowly/controlled ; has described the developing process and researching progress for the releasing fertilizer slowly/controlled abroad and at home; has prospected the developing tendency of the releasing fertilizer slowly/ controlled.%介绍了缓/控释肥料的定义和类型;阐述了国内外缓/控释肥料的发展历程和研究进展;展望了缓/控释肥料的发展趋势。

  6. A Health Belief Model-Social Learning Theory approach to adolescents' fertility control: findings from a controlled field trial.

    Science.gov (United States)

    Eisen, M; Zellman, G L; McAlister, A L

    1992-01-01

    We evaluated an 8- to 12-hour Health Belief Model-Social Learning Theory (HBM-SLT)-based sex education program against several community- and school-based interventions in a controlled field experiment. Data on sexual and contraceptive behavior were collected from 1,444 adolescents unselected for gender, race/ethnicity, or virginity status in a pretest-posttest design. Over 60% completed the one-year follow-up. Multivariate analyses were conducted separately for each preintervention virginity status by gender grouping. The results revealed differential program impacts. First, for preintervention virgins, there were no gender or intervention differences in abstinence maintenance over the follow-up year. Second, female preintervention Comparison program virgins used effective contraceptive methods more consistently than those who attended the HBM-SLT program (p less than 0.01); among males, the intervention programs were equally effective. Third, both interventions significantly increased contraceptive efficiency for teenagers who were sexually active before attending the programs. For males, the HBM-SLT program led to significantly greater follow-up contraceptive efficiency than the Comparison program with preintervention contraceptive efficiency controlled (p less than 0.05); for females, the programs produced equivalent improvement. Implications for program planning and evaluation are discussed.

  7. The Effects of Controlled Release Fertilizer on Apple Orchard Root Domain Environment%控释肥对苹果根域环境的影响

    Institute of Scientific and Technical Information of China (English)

    高文胜; 秦旭; 陈宏坤; 李芳东; 王敏; 李林光; 杨力

    2012-01-01

    The effects of controlled release fertilizer on apple orchard was studied including soil microbes,organic matter,pH value,mineral elements contents such as N,P,K,Ca,Mg,Cu,Fe,Zn,Mn by the applying apple special controlled release fertilizer with different experiment's treatment.Results showed that,compared with treatments common compound fertilizer applied,application of controlled release fertilizer increased contents of soil microbial biomass nitrogen,soil microbial biomass carbon,pH value,soil available N,Fe and Zn,and decreased the contents of soil available P,soil exchangeable Ca,Mg and Mn,but there was no significant difference with content of organic matter.Contents of available potassium in different experimental sites were different,and most of the indicators of different treatments CRFs applied were not significant difference.%采用苹果专用控释肥,设计不同试验处理,研究控释肥对果园土壤微生物,有机质,pH值和N、P、K、Ca、Mg、Cu、Fe、Zn、Mn等矿质元素含量的影响。结果表明,与普通复合肥相比,控释肥提高了果园土壤微生物量氮、微生物量碳和pH值,对有机质含量影响差异不明显;增加了土壤碱解氮、Fe和Zn含量,降低了土壤速效磷、交换性Ca、交换性Mg和Mn的含量,不同试验点速效钾和Cu的含量结果不一致;不同控释肥处理间大部分指标差异不明显。

  8. 控释氮肥在小麦上的示范应用效果%Application Effect of Controlled-Release Nitrogen Fertilizer on Wheat

    Institute of Scientific and Technical Information of China (English)

    于立芝; 史桂萍; 孙治军

    2014-01-01

    采用田间示范试验研究了控释氮肥在小麦上的应用效果。结果表明:使用控释肥,降低纯氮30%,小麦的公顷穗数、穗粒数、千粒重均有所增加,前诸留村的增产率为9.9%,中村的增产率为7.9%;降低纯氮50%,小麦的穗粒数基本不变,而千粒重增加0.3 g,增产率为3.5%;控释氮肥施用量降氮30%的示范应用效果明显优于降氮50%的。%The application effect of controlled -release nitrogen fertilizer on wheat was researched by field demonstration test .The results showed that the use of controlled -release nitrogen fertilizer to reduce 30% of pure nitrogen increased the spike number per hectare , grain number per spike and 1 000-grain weight; the yield of the villages Qianzhuliucun and Zhongcun increased by 9.9%and 7.9%respectively .The use of con-trolled-release fertilizer to reduce 50%of pure nitrogen could increase 0.3 g of 1 000-grain weight but change fewer in grain number per spike , so the yield increased by 3.5%.The application effect of controlled -release nitrogen fertilizer reducing 30%pure nitrogen was obviously better than that reducing 50%nitrogen .

  9. Effect of Controlled Release Nitrogen Fertilizer on Rapeseed Yield, Agronomic Characters and Soil Fertility%施用控释氮肥对油菜产量、农艺性状及土壤肥力的影响

    Institute of Scientific and Technical Information of China (English)

    孙玉桃; 鲁艳红; 聂军; 廖育林; 谢坚; 杨曾平; 周兴

    2014-01-01

    为了探讨控释氮肥对油菜的肥料效应,通过池栽试验,选取洞庭湖区3种主要土壤在连续4年“稻-稻-冬闲”后将冬闲改种油菜施用旱作控释氮肥,研究控释氮肥对油菜产量、农艺性状、生长性状及土壤肥力的影响。结果表明,在紫潮泥及河沙泥2种土壤中施用控释氮肥促进了油菜植株的生长发育,可获得较高油菜产量,比施等N量尿素处理分别增产12.2%和9.8%,70%控释氮肥效果明显降低。施用控释氮肥后河沙泥土壤碱解氮和有机碳含量比油菜试验前分别增加25.0%和3.2%,紫潮泥碱解氮含量提高13.5%,并均高于尿素和70%控释氮肥2个处理。而红黄泥施用控释氮肥对油菜产量和土壤肥力的影响均不及等N量尿素处理,70%控释氮肥处理的效应则更小。施用控释氮肥对紫潮泥及河沙泥的油菜生产具有显著增产效果及土壤氮素肥力提升作用。%In order to study the effects of controlled release nitrogen fertilizer (CRNF) on rapeseed, a simulated experiment was adopted with 3 types of paddy soils in Dong-Ting Lake area after 4-years of continuous applying CRNF under double rice cropping and fallow system and the fallow changed to rapeseed. The effect of controlled release fertilizer on rapeseed yield, agronomic characters and soil fertility were studied in this paper. The results showed that CRNF improved the growth of rapeseed plant and the highest grain yield occurred in CRNF treatments in purple calcareous clayed paddy soil (PCS) and alluvial loamy paddy soil (ALS) which increased by 12.2%and 9.8%, respectively, compared with applying urea (CF treatment). Yield in 70%CRNF treatment decreased obviously compared with CF treatment. Contents of available N and organic carbon in soil increased by 25.0%and 3.2%after rapeseed cropping than before rapeseed cropping under CRNF treatment in ALS, and available N increased by 13.5%in PCS. Both rapeseed yield and soil

  10. Human Homeostatic Control Matrix in Norm

    Directory of Open Access Journals (Sweden)

    Alexander G. Kruglov

    2016-09-01

    Full Text Available We undertook our research to study and systemize the relationship between hemodynamics and biochemical parameters of arterial and venous blood in healthy people. Hemodynamic and biochemical characteristics were obtained through a probe by using catheterization in various vascular areas (aorta, brain, heart, lungs, and liver. Correlation and factor analyses were conducted to study the relationship between the obtained characteristics of the regional and systemic blood flow. Due to the nature of the correlation analysis, the significant (p<0.05 relation signs (+, 0, - without regard to their power were considered. The obtained results suggested that there are sets of both intra-organ and system regulatory relationships between metabolic and hemodynamic characteristics. The complex of relationships among the studied parameters makes it possible to maintain the homeostatic equilibrium in the body. The psychophysiological control system includes the subsystems we described: 1 the cardiac-hepatic-pulmonary complex having properties of the metabolic and hemodynamic information field providing biological stability of the homeostasis; any significant imbalance of its elements triggers afferent information flows actualizing an afferent synthesis; 2 the mind forming gradient patterns of targeted behavior to eliminate metabolic imbalance, to achieve goals both as coded biological parameters and as the highest forms of behavior, to reach the ultimate goal: parametric, homeostatic equilibrium in the “biosphere” of the human body. By using the results of our research and the complex of dynamic relationships in human homeostasis, we built a homeostatic control matrix (HCM.

  11. Fertility incentives and disincentives.

    Science.gov (United States)

    Financioglu, N

    1984-06-01

    Some 40 countries use some form of incentives and disincentives in support of population policies, about half with the aim of reducing fertility and half with the aim of increasing it. These schemes range from limitations on tax and family allowances or maternity benefits after a given family size has been reached to payments to acceptors of fertility control methods. Some schemes aim to eliminate or reduce the cost and inconvenience people may face in achieving their fertility preferences, whereas others contain an element of deterrence. It is difficult to isolate and measure the impact of incentives on fertility from the effects of other factors such as family planning service availability or modernization. Studies in pronatalist countries suggest that incentive schemes produce short-term fertility increases without a change in average family size. Monetary incentives must be constantly increased to keep pace with inflation, placing a heavy burden on government budgets. Administrative capacity to operate the scheme is critical in terms of both manpower and efficient systems for record keeping, monitoring, and close supervision to prevent abuse. There is also considerable debate on the moral and ethical implications of incentives and disincentives as policy tools. Incentives offered for the acceptance of a particular fertility control method potentially contravene the principle of voluntary and informed consent. In addition, the relative value of the reward is greater for those in the lower income groups. The discriminatory nature of certain types of incentives and disincentives is illustrated by measures introduced in Singapore that give highest priority in school enrollment to the children of highly educated mothers with 2-3 children. This ruling is expected to further intensify the controversy surrounding incentive and disincentive schemes.

  12. Impact of GnRH analogues on oocyte/embryo quality and embryo development in in vitro fertilization/intracytoplasmic sperm injection cycles: a case control study

    Directory of Open Access Journals (Sweden)

    Rigó János

    2009-09-01

    Full Text Available Abstract Background Despite the clinical outcomes of ovarian stimulation with either GnRH-agonist or GnRH-antagonist analogues for in vitro fertilization (IVF being well analysed, the effect of analogues on oocyte/embryo quality and embryo development is still not known in detail. The aim of this case-control study was to compare the efficacy of a multiple-dose GnRH antagonist protocol with that of the GnRH agonist long protocol with a view to oocyte and embryo quality, embryo development and IVF treatment outcome. Methods Between October 2001 and December 2008, 100 patients were stimulated with human menopausal gonadotrophin (HMG and GnRH antagonist in their first treatment cycle for IVF or intracytoplasmic sperm injection (ICSI. One hundred combined GnRH agonist + HMG (long protocol cycles were matched to the GnRH antagonist + HMG cycles by age, BMI, baseline FSH levels and by cause of infertility. We determined the number and quality of retrieved oocytes, the rate of early-cleavage embryos, the morphology and development of embryos, as well as clinical pregnancy rates. Statistical analysis was performed using Wilcoxon's matched pairs rank sum test and McNemar's chi-square test. P Results The rate of cytoplasmic abnormalities in retrieved oocytes was significantly higher with the use of GnRH antagonist than in GnRH agonist cycles (62.1% vs. 49.9%; P Conclusion Antagonist seemed to influence favourably some parameters of early embryo development dynamics, while other morphological parameters seemed not to be altered according to GnRH analogue used for ovarian stimulation in IVF cycles.

  13. Women's education and fertility behaviour.

    Science.gov (United States)

    1993-12-01

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

  14. The research of controlled release fertilizer experiment of corn on Ningxia south mountain area%宁夏南部山区玉米控释肥肥效试验

    Institute of Scientific and Technical Information of China (English)

    火勇

    2015-01-01

    Controlled release fertilizer had the advantages of reducing nitrogen nutrient volatilization and improving utilization rate of fertilizer.Controlled release fertilizer experiment results in Ningxia south mountainous showed that an average yield of corn was 11 096.1 kg/hm2 with the application of controlled release fertilizer, which was 9.0% higher than that of the custom fertilizer application;the yield of basal application 90 kg/hm2 controlled release fertilizer with 90 days was high and the benefit was good, which was 14.3%higher than yield of the custom fertilizer application and increased 2 145.66 yuan/hm 2.%控释肥具有减少氮素养分挥发,提高肥料利用率等优点,控释肥在宁夏南部山区试验结果表明,施用控释肥平均产量11096.1 kg/hm2,较习惯施肥增产9.0%,基施90 d控释肥600 kg/hm2产量高,效益好,较习惯施肥增产14.3%,增收2145.66元/hm2。

  15. 控释肥不同施用方式对玉米产量的影响研究%A Study of the Effect of Different Application Methods of Controlled Release Fertilizer on Corn Yields

    Institute of Scientific and Technical Information of China (English)

    周洋

    2012-01-01

    同心县玉米控释肥不同施用方式试验结果表明:采用播种前旋耕施控释肥10~15 cm深,玉米产量最高,为18 450kg/hm2。%The results of the test for different application methods of controlled release fertilizer for corn shows that a highest yield, 18 450 kg/hm2, was achieved when adopting rotary tillage fertilization 10-15 cm depth of controlled release fertilizer before seeding.

  16. Fuzzy Control Strategies in Human Operator and Sport Modeling

    CERN Document Server

    Ivancevic, Tijana T; Markovic, Sasa

    2009-01-01

    The motivation behind mathematically modeling the human operator is to help explain the response characteristics of the complex dynamical system including the human manual controller. In this paper, we present two different fuzzy logic strategies for human operator and sport modeling: fixed fuzzy-logic inference control and adaptive fuzzy-logic control, including neuro-fuzzy-fractal control. As an application of the presented fuzzy strategies, we present a fuzzy-control based tennis simulator.

  17. 控释复合肥对草莓生长发育、品质及经济效益的影响%Effects of Controlled Release Fertilizer on Growth, Quality and Economic Benefit of Strawberry

    Institute of Scientific and Technical Information of China (English)

    冯志文; 宋凯; 王翠玲; 张继祥

    2011-01-01

    In order to find appropriate fertilizer for the growth of strawberry in greenhouse, with " All -Star" strawberry(Fragaria ananassa Duch cv. "All Star" )as test material, a greenhouse experiment was conducted to study the effects of controlled release fertilizer on the growth potential, fruit yield and quality and fertilizer use efficiency. The results showed that controlled release fertilizer could significantly enhance the stem thickness, plant height and leaf area of strawberry compared to common fertilizer. The effects of controlled release fertilizer on photosynthetic rate, chlorophyll content, and root vigor of strawberry were significantly higher than those of common fertilizer, and always kept higher level. Compared to no fertilizer treatment, the fertilizer treatments decreased the quality of strawberry, but the influence of controlled release fertilizer on quality of strawberry was smaller than that of the common fertilizer. In the agronomic efficiency of nitrogen, potassium and phosphorus, the controlled release fertilizer was always higher than common fertilizer.%通过对等量肥效的控释肥和普通化肥处理的“全明星”草莓生长发育、产量品质以及肥料利用效率的研究发现,控释肥处理草莓的茎粗、株高及叶面积显著高于普通化肥处理;控释肥处理草莓的叶片光合速率、叶绿素含量、根系活力显著高于普通化肥处理,并一直维持较高水平;与对照相比,各肥料处理草莓的品质有所下降,但控释肥处理的下降幅度较小,对品质的影响低于普通化肥处理;在氮磷钾的农学利用效率方面,控释肥处理始终高于普通化肥处理.

  18. 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

  19. Fertility, Migration, and Altruism

    OpenAIRE

    2000-01-01

    Consider migration to a higher income region as a human capital investment in which parents bear migration costs and children share returns. Migrants from a population with heterogeneous intergenerational discount rates will be self-selected on intergenerational altruism. Thus, immigrants may be self-selected on fertility. Soviet Jews who migrate to Israel despite high migration costs have significantly more children than members of the same birth cohort who migrate later when costs are low. ...

  20. 缓控释肥对烟草生长和烟叶品质的影响研究进展%Research Progress on Effects of Slow-Controlled Release Fertilizer on Growth and Quality of Tobacco

    Institute of Scientific and Technical Information of China (English)

    朱换换; 符雷; 曾代龙; 祝春岗; 时向东

    2014-01-01

    The effects of slow -controlled release fertilizer on effectiveness of soil nutrients , tobacco growth and quality were summarized in this paper .The development of slow -controlled release fertilizer was also prospected .%本文综述了缓控释肥对土壤养分有效性、烟草生长和烟叶品质的影响,并对缓控释肥在未来的发展前景进行了展望。

  1. Adolescent fertility: worldwide concerns.

    Science.gov (United States)

    Senderowitz, J; Paxman, J M

    1985-04-01

    There is growing concern over the adverse health, social, economic, and demographic effects of adolescent fertility. Morbidity and mortality rates ar significantly higher for teenage mothers and their infants, and early initiation of childbearing generally means truncated education, lower future family income, and larger completed family size. Adolescent fertility rates, which largely reflect marriage patterns, range from 4/1000 in Mauritania; in sub-Saharan Africa, virtually all rates are over 100. In most countries, adolescent fertility rates are declining due to rising age at marriage, increased educational and economic opportunities for young women, changes in social customs, increased use of contraception, and access to abortion. However, even if fertility rates were to decline dramatically among adolescent women in developing countries, their sheer numbers imply that their fertility will have a major impact on world population growth in the years ahead. The number of women in the world ages 15-19 years is expected to increase from 245 million in 1985 to over 320 million in the years 2020; 82% of these women live in developing countries. As a result of more and earlier premarital sexual activity, fostered by the lengthening gap between puberty and marriage, diminished parental and social controls, and increasing peer and media pressure to be sexually active, abortion and out-of-wedlock childbearing are increasing among teenagers in many developed and rapidly urbanizing developing countries. Laws and policies regarding sex education in the schools and access to family planning services by adolescents can either inhibit or support efforts to reduce adolescent fertility. Since contraceptive use is often sporadic and ineffective among adolescents, family planning services are crucial. Such programs should aim to reduce adolescents' dependence on abortion through preventive measures and increase awareness of the benefits of delayed sexual activity. Similarly, sex

  2. Trichoderma harzianum strain SQR-T37 and its bio-organic fertilizer could control Rhizoctonia solani damping-off disease in cucumber seedlings mainly by the mycoparasitism.

    Science.gov (United States)

    Huang, Xinqi; Chen, Lihua; Ran, Wei; Shen, Qirong; Yang, Xingming

    2011-08-01

    Damping-off disease is caused by Rhizoctonia solani and leads to serious loss in many crops. Biological control is an efficient and environmentally friendly way to prevent damping-off disease. Optical micrographs, scanning electron micrographs, and the determination of hydrolytic enzymes were used to investigate the antagonism of Trichoderma harzianum SQR-T37 (SQR-T37) against R. solani. Experiments were performed in pots to assess the in vivo disease-control efficiency of SQR-T37 and bio-organic fertilizer. The results indicate that the mycoparasitism was the main mechanism accounting for the antagonistic activity of SQR-T37. In one experiment, the population of R. solani was decreased from 10(6) internal transcribed spacer (ITS) copies per gram soil to 10(4) ITS copies per gram soil by the presence of the antagonist. In this experiment, 45% of the control efficiency was obtained when 8 g of SQR-T37 hyphae per gram soil was applied. In a second experiment, as much as 81.82% of the control efficiency was obtained when bio-organic fertilizer (SQR-T37 fermented organic fertilizer, BIO) was applied compared to only 27.27% of the control efficiency when only 4 g of SQR-T37 hyphae per gram soil was applied. Twenty days after incubation, the population of T. harzianum was 4.12 × 10(7) ITS copies per gram soil in the BIO treatment, which was much higher than that in the previous treatment (8.77 × 10(5) ITS copies per gram soil), where only SQR-T37 was applied. The results indicated that SQR-T37 was a potent antagonist against R. solani in a mycoparasitic way that decreased the population of the pathogen. Applying BIO was more efficient than SQR-T37 application alone because it stabilized the population of the antagonist.

  3. 我国保水缓/控释肥料的研发进展%Research progress and development of water-storing slow/controlled release fertilizers in China

    Institute of Scientific and Technical Information of China (English)

    党民团; 刘娟

    2011-01-01

    The water-storing slow/controlled release fertilizer is the new value-added fertilizer in low carbon economy era, as well as one of the most promising fertilizers in the future fertilizer industry. The research progress and development of water-storing slow/controlled release fertilizers in china are reviewed, four kinds of composite integration technologies for water-storing and fertilizer are introduced with the analysises on existing problems, some strategies are provided for the further research and development of water-storing slow/controlled release fertilizers in China.%保水缓/控释肥料是低碳经济时代的新型增值肥料,是未来肥料产业最具前景的重要方向之一。综述了近年来我国保水缓/控释肥料的研发进展和保水剂与肥料复合一体化技术的4种制备方法,分析了相关研发存在的问题,提出了我国保水缓/控释肥料开发应进一步采取的对策。

  4. Reflex control of human jaw muscles.

    Science.gov (United States)

    Türker, Kemal S

    2002-01-01

    The aim of this review is to discuss what is known about the reflex control of the human masticatory system and to propose a method for standardized investigation. Literature regarding the current knowledge of activation of jaw muscles, receptors involved in the feedback control, and reflex pathways is discussed. The reflexes are discussed under the headings of the stimulation conditions. This was deliberately done to remind the reader that under each stimulation condition, several receptor systems are activated, and that it is not yet possible to stimulate only one afferent system in isolation in human mastication experiments. To achieve a method for uniform investigation, we need to set a method for stimulation of the afferent pathway under study with minimal simultaneous activation of other receptor systems. This stimulation should also be done in an efficient and reproducible way. To substantiate our conviction to standardize the stimulus type and parameters, we discuss the advantages and disadvantages of mechanical and electrical stimuli. For mechanical stimulus to be delivered in a reproducible way, the following precautions are suggested: The stimulus delivery system (often a probe attached to a vibrator) should be brought into secure contact with the area of stimulation. To minimize the slack between the probe, the area to be stimulated should be taken up by the application of pre-load, and the delivered force should be recorded in series. Electrical stimulus has advantages in that it can be delivered in a reproducible way, though its physiological relevance can be questioned. It is also necessary to standardize the method for recording and analyzing the responses of the motoneurons to the stimulation. For that, a new technique is introduced, and its advantages over the currently used methods are discussed. The new method can illustrate the synaptic potential that is induced in the motoneurons without the errors that are unavoidable in the current

  5. 控释BB肥对西瓜生长期土壤酶活性的影响%Effects of Controlled-release BB Fertilizer on Soil Enzymes Activities during Watermelon Growing Period

    Institute of Scientific and Technical Information of China (English)

    井大炜; 杨广怀; 马文丽; 刘春生

    2009-01-01

    The study aimed to study the effects of controlled-release BB fertilizer (fertilizer blending) applied on soil enzymes activities and provided the theoretical base for the population of controlled-release fertilizer. In the field plot test, the effect of the controlled-release BB fertilizer on soil urease, neutral phosphatase and sucrose enzymes activities during different growth stages of watermelon were studied. The results showed with the application of controlled-release BB fertilizer, the activities of these three enzymes were better than conven-tional fertilizer treatment because of the significantly controlled release effects of the controlled-release BB fer-tilizer.%研究控释BB肥(掺混肥)对土壤中酶活性的影响,为控释肥的推广使用提供理论依据.采用田间小区试验法研究了控释BB肥对西瓜不同生育期土壤脲酶、中性磷酸酶和蔗糖酶活性的影响.在试验条件下,由于控释BB肥对养分的显著控释效果,它的施用对土壤中这三种酶活性的影响要好于习惯施肥处理.

  6. The Fertility Transition in Bavaria

    OpenAIRE

    Brown, John C.; Timothy W. Guinnane

    2001-01-01

    The decline of human fertility that occurred in Europe and North America in the nineteenth century, and elsewhere in the twentieth century, remains a topic of debate largely because there is no accepted explanation for the event. Disagreement persists in part because researchers have rarely used the detailed quantitative information necessary to form adequate tests of alternative theories. This paper uses district-level data from Bavaria to study the correlates of the decline of fertility in ...

  7. Effects of Coated Controlled-release Blend Bulk Fertilizers on Yield,Quality and Nutrient Content of Scallion%包膜控释BB肥对大葱产量、品质及养分含量的影响

    Institute of Scientific and Technical Information of China (English)

    董亮; 张玉凤; 李彦; 张英鹏; 孙明; 杨力; 陈广思; 于淑芳

    2011-01-01

    The effects of different coated controlled-release blend bulk fertilizers and decreasing coated controlled-release blend bulk fertilizers on scallion's yield, quality and nutrient content were studied by field experiment. The results showed that fertilizers could increase the scallion's yield. In all the coated controlled-release fertilizers, controlled-release fertilizer Ⅱ was the best which could improve the scallion's yield by 2. 57% compared with traditional fertilizer. Scallion's quality was also improved after using coated controlled-release blend bulk fertilizers. Vc content was increased by 1.64%-14. 29% , nitrate content was decreased by 23. 18% -39. 71 % . The coated controlled-release fertilizer Ⅱ showed the best effect on Vc content improvement and nitrate content control. In all tested treatments of fertilizers, the highest contents of nitrogen, phosphorus and potassium in scallion were detected in the coated controlled-release fertilizer Ⅰ,Ⅲ and Ⅱ , respectively. But there was no significant difference in three coated controlled-release fertilizers.%通过大田试验,探索了不同养分比例的包膜控释BB肥及控释BB肥减量化施用对章丘大葱产量、品质及养分含量的影响.结果表明,本试验条件下,施肥能明显增加大葱产量,而在所有包膜控释肥处理中,以包膜控释肥II处理的大葱产量最高,与习惯施肥相比,增幅为2.57%.施用包膜控释BB肥亦能显著提高大葱品质.包膜控释BB肥可以使大葱中Vc含量提高1.64%~14.29%,硝酸盐含量降低23.18% ~39.71%,其中,以包膜控释肥Ⅱ在提高大葱Vc、降低硝酸盐含量方面效果最佳.在大葱养分含量方面,包膜控释肥工处理的大葱吸氮量最高,包膜控释肥m处理的大葱吸磷量最高,包膜控释肥n处理的大葱吸钾量最高,但3种包膜控释肥处理之间差异不显著.

  8. HOW TO SELECT APPROPRIATE HUMAN RESOURCE CONTROLLING INDICATORS

    Directory of Open Access Journals (Sweden)

    Monika Dugelova

    2015-09-01

    Full Text Available Human resource controlling represents a company’s strategic method to support its role is planning, checking, and managing—including information supplement for human resources department. Human resource controlling helps with optimization and transformation of human resource functions and with general human resource management. Our survey deals with the implementation of human resource controlling in information technology companies. The selection of appropriate human resource controlling tools is the most important part of implementation. This article deals with the problem of human resource indicators selection as the most frequently used human resource controlling tool. Many international authors have solved the problem of performance appraisal measurement, and there are numerous demonstrations on how to choose key performance indicators. Our motivation to draft the complex methodology of human resource indicators selection is based on non-existing solution among the authors. To solve the problem and find appropriate methodology, we use the methods comparison, abstraction, and concretization. The result is a creation of the right human resource indicators selection in line with human resource controlling aim. We use the Balanced Scorecard, Deloitte human resource strategy framework, and partial solution of Kleinhempel (2010. These results constitute the basis for our future research and for drafting the whole methodology of human resource controlling implementation in information technology companies.

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

    Directory of Open Access Journals (Sweden)

    Takafumi Kinoshita

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

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

    Science.gov (United States)

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

    2014-01-01

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

  11. The Effects of Fungicide, Soil Fumigant, Bio-Organic Fertilizer and Their Combined Application on Chrysanthemum Fusarium Wilt Controlling, Soil Enzyme Activities and Microbial Properties.

    Science.gov (United States)

    Zhao, Shuang; Chen, Xi; Deng, Shiping; Dong, Xuena; Song, Aiping; Yao, Jianjun; Fang, Weimin; Chen, Fadi

    2016-04-21

    Sustained monoculture often leads to a decline in soil quality, in particular to the build-up of pathogen populations, a problem that is conventionally addressed by the use of either fungicide and/or soil fumigation. This practice is no longer considered to be either environmentally sustainable or safe. While the application of organic fertilizer is seen as a means of combating declining soil fertility, it has also been suggested as providing some control over certain soil-borne plant pathogens. Here, a greenhouse comparison was made of the Fusarium wilt control efficacy of various treatments given to a soil in which chrysanthemum had been produced continuously for many years. The treatments comprised the fungicide carbendazim (MBC), the soil fumigant dazomet (DAZ), the incorporation of a Paenibacillus polymyxa SQR21 (P. polymyxa SQR21, fungal antagonist) enhanced bio-organic fertilizer (BOF), and applications of BOF combined with either MBC or DAZ. Data suggest that all the treatments evaluated show good control over Fusarium wilt. The MBC and DAZ treatments were effective in suppressing the disease, but led to significant decrease in urease activity and no enhancement of catalase activity in the rhizosphere soils. BOF including treatments showed significant enhancement in soil enzyme activities and microbial communities compared to the MBC and DAZ, evidenced by differences in bacterial/fungi (B/F) ratios, Shannon-Wiener indexes and urease, catalase and sucrase activities in the rhizosphere soil of chrysanthemum. Of all the treatments evaluated, DAZ/BOF application not only greatly suppressed Fusarium wilt and enhanced soil enzyme activities and microbial communities but also promoted the quality of chrysanthemum obviously. Our findings suggest that combined BOF with DAZ could more effectively control Fusarium wilt disease of chrysanthemum.

  12. 高反应人群超排卵%Controlled ovarian stimulation for high responder women undergoing in vitro fertilization

    Institute of Scientific and Technical Information of China (English)

    叶虹

    2012-01-01

    High responder women are characterized by high response to exogenous gonadotrophin therapy manifested hy recruitment of a large number of follicles, rapid estradiol response and significant cancellation rate due to the potential risk of ovarian hyperstimulation syndrome (OHSS) during in vitro fertilization-embryo transfer. Even for those patients who progress to oocyte retrieval and embryo transfer, appreciably lower fertilization rate and chromosomally normal blastocyst development rate are found. The super ovulation strategies for high responder women are included to reduce excessive ovarian stimulation and avoid OHSS by several approaches, such as dual suppression with oral contraceptives and GnRH agonist, reduced doses of GnRH agonist, GnRH antagonist protocol and GnRH agonist instead of hCG to trigger the final oocyte maturation, gonadotrophins step up and step down, different gonadotrophins for ovarian stimulation, application of metf ormin, and mild ovarian stimulation.

  13. Soil fertility controls soil-atmosphere carbon dioxide and methane fluxes in a tropical landscape converted from lowland forest to rubber and oil palm plantations

    Science.gov (United States)

    Hassler, E.; Corre, M. D.; Tjoa, A.; Damris, M.; Utami, S. R.; Veldkamp, E.

    2015-10-01

    Expansion of palm oil and rubber production, for which global demand is increasing, causes rapid deforestation in Sumatra, Indonesia, and is expected to continue in the next decades. Our study aimed to (1) quantify changes in soil CO2 and CH4 fluxes with land-use change and (2) determine their controlling factors. In Jambi Province, Sumatra, we selected two landscapes on heavily weathered soils that differ mainly in texture: loam and clay Acrisol soils. In each landscape, we investigated the reference land-use types (forest and secondary forest with regenerating rubber) and the converted land-use types (rubber, 7-17 years old, and oil palm plantations, 9-16 years old). We measured soil CO2 and CH4 fluxes monthly from December 2012 to December 2013. Annual soil CO2 fluxes from the reference land-use types were correlated with soil fertility: low extractable phosphorus (P) coincided with high annual CO2 fluxes from the loam Acrisol soil that had lower fertility than the clay Acrisol soil (P oil palm (107.2 to 115.7 mg C m-2 h-1) decreased compared to the other land-use types (between 178.7 and 195.9 mg C m-2 h-1; P oil palm were the result of strongly decomposed soil organic matter and reduced soil C stocks due to reduced litter input as well as being due to a possible reduction in C allocation to roots due to improved soil fertility from liming and P fertilization in these plantations. Soil CH4 uptake in the reference land-use types was negatively correlated with net nitrogen (N) mineralization and soil mineral N, suggesting N limitation of CH4 uptake, and positively correlated with exchangeable aluminum (Al), indicating a decrease in methanotrophic activity at high Al saturation. Reduction in soil CH4 uptake in the converted land-use types (ranging from -3.0 to -14.9 μg C m-2 h-1) compared to the reference land-use types (ranging from -20.8 to -40.3 μg C m-2 h-1; P < 0.01) was due to a decrease in soil N availability in the converted land-use types. Our study

  14. [Japan-U.S. comparison of the effectiveness of fertility control--the analysis of the incidence of unplanned births (author's transl)].

    Science.gov (United States)

    Nohara Atoh, M

    1982-01-01

    Our major concern in this paper is how Japan could maintain 1 of the lowest levels of fertility in the industrialized world in the 1960s despite the fact that in Japan the proportion of those using contraception is smaller, the main contraceptive method is less efficient, and contraception is initiated at a later stage of reproductive life than in the Western countries. Drawing on the Japanese version of the World Fertility Survey in 1974 and the 1970 National Fertility Study from the US, we compared the effectiveness of fertility control in Japan and the US by focusing on the incidence of unplanned and unwanted births and attempted to clarify the reason for the difference in that incidence by breaking it down into several fertility control factors. The findings were as follows. 1) There is a smaller proportion who opt to delay childbearing in the early reproductive stage in Japan than in the US, and the probability of having a birth as a timing failure is somewhat higher in Japan than in the US. This is due to the fact that contraceptive efficacy for those who delay is lower than that of Americans. In the early reproductive years or when the purpose is for spacing births, induced abortion is used mainly by noncontraceptors. It is rare to find cases of induced abortion backing contraceptive failures at such an early stage. 2) At the later stages of childbearing, a larger proportion of women choose to terminate childbearing in Japan than in the US. The probability of having unwanted high order births is much lower in Japan than in the US. This is partly because contraceptive efficacy is somewhat higher in Japan and partly because induced abortion is used by noncontraceptive terminators. It is mainly because of the use of abortion as backup by contraceptors who choose to terminate unwanted pregnancies. 3) In Japan, those who do not use contraception as a means for avoiding unplanned births rely on induced abortion more or less equally at different stages of their

  15. Co-digestion of rice straw and cow dung to supply cooking fuel and fertilizers in rural India: Impact on human health, resource flows and climate change.

    Science.gov (United States)

    Sfez, Sophie; De Meester, Steven; Dewulf, Jo

    2017-12-31

    Anaerobic digestion of cow dung with new feedstock such as crop residues to increase the biogas potential is an option to help overcoming several issues faced by India. Anaerobic digestion provides biogas that can replace biomass cooking fuels and reduce indoor air pollution. It also provides digestate, a fertilizer that can contribute to compensate nutrient shortage on agricultural land. Moreover, it avoids the burning of rice straw in the fields which contributes to air pollution in India and climate change globally. Not only the technical and economical feasibility but also the environmental sustainability of such systems needs to be assessed. The potential effects of implementing community digesters co-digesting cow dung and rice straw on carbon and nutrients flows, human health, resource efficiency and climate change are analyzed by conducting a Substance Flow Analysis and a Life Cycle Assessment. The implementation of the technology is considered at the level of the state of Chhattisgarh. Implementing this scenario reduces the dependency of the rural community to nitrogen and phosphorus from synthetic fertilizers only by 0.1 and 1.6%, respectively, but the dependency of farmers to potassium from synthetic fertilizers by 31%. The prospective scenario returns more organic carbon to agricultural land and thus has a potential positive effect on soil quality. The implementation of the prospective scenario can reduce the health impact of the local population by 48%, increase the resource efficiency of the system by 60% and lower the impact on climate change by 13%. This study highlights the large potential of anaerobic digestion to overcome the aforementioned issues faced by India. It demonstrates the need to couple local and global assessments and to conduct analyses at the substance level to assess the sustainability of such systems. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Perbandingan Angka Fertilitas dan Hambatan Perkembangan Embrio Mencit yang Dikultur dalam Medium M16 dan Human Tubal Fluid (THE COMPARISON OF MICE FERTILITY RATE AND EMBRYONIC DEVELOPMENT CELL BLOCK WHEN CULTURED IN M16 AND HUMAN TUBAL FLUID MEDIA

    Directory of Open Access Journals (Sweden)

    Widjiati .

    2013-07-01

    Full Text Available The aim of this research was to compare the fertility rate and embryonic development cell block ofmice when cultured in M16 and Human Tubal Fluid (HTF media, respectively. Two months old femaleBalbC mice were super ovulated using Pregnant Mare Serum Gonadotrophin (PMSG and Human ChorionicGonadotrophin (HCG prior to mating with vasectomies mice. At 17 hours post mating the mice wassacrificed for the collections of egg cells and spermatozoa. Egg cells were collected by tearing the fertilizationsac, while the sperm were collected from caudal epididymis. After the collection, both the egg cells andsperm were put in Petri dish containing M16 and HTF media and kept in 5% CO2 incubator at 370C for onehour prior to the in vitro fertilization (IVF was performed. In vitro fertilization was performed in 5% CO2 incubator at 370C and kept for 24 hours in M16 and in HTF culture media. The results showed thatfertilization rate was 98.09% and 99.57%; cell block embryonic development was 85.09% and 83.36%when cultured in M16 and HTF media, respectively. In conclusion, HTF media can be used for culturingmouse embryo.

  17. Assessment of early cleaving in vitro fertilized human embryos at the 2-cell stage before transfer improves embryo selection.

    Science.gov (United States)

    Sakkas, D; Percival, G; D'Arcy, Y; Sharif, K; Afnan, M

    2001-12-01

    To determine the most viable embryos for transfer. Study 1: Preselection of early-cleaving 2-cell embryos for transfer. Study 2: Alternating weeks during which preselection was performed and not performed. ART program, Birmingham Women's Hospital, Birmingham, United Kingdom. Patients undergoing IVF or ICSI cycles with transfer on day 2. Culture of all fertilized embryos. Number of fertilized embryos cleaving to the 2-cell stage on day 1, embryo quality, implantation rates, and pregnancy rates. Patients with early-cleaving 2-cell embryos had significantly higher pregnancy and implantation rates (45 of 100 [45.0%] and 58 of 219 [25.5%], respectively) than did patients without early-cleaving 2-cell embryos (31 of 130 [23.8%] and 43 of 290 [14.8%], respectively). In weeks during which preselection was used, the overall pregnancy and implantation rates of the clinic improved. The presence of early-cleaving 2-cell embryos improves a patient's chance of achieving pregnancy. Use of more stringent embryo selection criteria can improve overall pregnancy rates.

  18. Metric Selection for Evaluation of Human Supervisory Control Systems

    Science.gov (United States)

    2009-12-01

    Conceptual model of human-supervisory control (modified from Pina , Cummings et al. (2008...42  4 LIST OF TABLES Table 1. Human supervisory control metric classes ( Pina , Donmez...literature in terms of human- autonomous vehicle interaction (Crandall & Cummings, 2007; Olsen & Goodrich, 2003; Pina , Cummings, Crandall, & Della Penna

  19. Controlled toothbrush abrasion of softened human enamel.

    Science.gov (United States)

    Voronets, J; Jaeggi, T; Buergin, W; Lussi, A

    2008-01-01

    The aim of this in vitro study was to compare toothbrush abrasion of softened enamel after brushing with two (soft and hard) toothbrushes. One hundred and fifty-six human enamel specimens were indented with a Knoop diamond. Salivary pellicle was formed in vitro over a period of 3 h. Erosive lesions were produced by means of 1% citric acid. A force-measuring device allowed a controlled toothbrushing force of 1.5 N. The specimens were brushed either in toothpaste slurry or with toothpaste in artificial saliva for 15 s. Enamel loss was calculated from the change in indentation depth of the same indent before and after abrasion. Mean surface losses (95% CI) were recorded in ten treatment groups: (1) soft toothbrush only [28 (17-39) nm]; (2) hard toothbrush only [25 (16-34) nm]; (3) soft toothbrush in Sensodyne MultiCare slurry [46 (27-65) nm]; (4) hard toothbrush in Sensodyne MultiCare slurry [45 (24-66) nm]; (5) soft toothbrush in Colgate sensation white slurry [71 (55-87) nm]; (6) hard toothbrush in Colgate sensation white slurry [85 (60-110) nm]; (7) soft toothbrush with Sensodyne MultiCare [48 (39-57) nm]; (8) hard toothbrush with Sensodyne MultiCare [40 (29-51) nm]; (9) soft toothbrush with Colgate sensation white [51 (37-65) nm]; (10) hard toothbrush with Colgate sensation white [52 (36-68) nm]. Neither soft nor hard toothbrushes produced significantly different toothbrush abrasion of softened human enamel in this model (p > 0.05). Copyright 2008 S. Karger AG, Basel.

  20. DCS控制系统在缓释肥生产中的应用%Application of DCS control system to slow release fertilizer production

    Institute of Scientific and Technical Information of China (English)

    石兆军

    2012-01-01

    The variable-ratio control, software configuration and equipment selection of DCS control system in slow release fertilizer production are introduced. DCS control system is used for 300 kt/a slow release fertilizer project in Jinshan Chemical Co., Ltd, the automatic control rate of equipment is 98%; the qualification rate of product is increased by 19 percentage points, reaching to 99%; the material cost of 14 RMB Yuan and energy of 8 kW·h can be saved every ton product; increasing the benefit 5.76 million RMB Yuan every year for enterprise.%介绍DCS控制系统在缓释肥生产中变比值控制方案和系统软件的配置,以及应用DCS控制系统的设备选型。金山化肥公司的300kt/a缓释肥项目采用DCS控制系统,设备自控率达到98%;产品合格率提高了19百分点,达到99%;生产每吨产品节约原料成本14元、节电8kW·h,每年为企业增加效益576万元。

  1. Sensorimotor integration in human postural control

    Science.gov (United States)

    Peterka, R. J.

    2002-01-01

    It is generally accepted that human bipedal upright stance is achieved by feedback mechanisms that generate an appropriate corrective torque based on body-sway motion detected primarily by visual, vestibular, and proprioceptive sensory systems. Because orientation information from the various senses is not always available (eyes closed) or accurate (compliant support surface), the postural control system must somehow adjust to maintain stance in a wide variety of environmental conditions. This is the sensorimotor integration problem that we investigated by evoking anterior-posterior (AP) body sway using pseudorandom rotation of the visual surround and/or support surface (amplitudes 0.5-8 degrees ) in both normal subjects and subjects with severe bilateral vestibular loss (VL). AP rotation of body center-of-mass (COM) was measured in response to six conditions offering different combinations of available sensory information. Stimulus-response data were analyzed using spectral analysis to compute transfer functions and coherence functions over a frequency range from 0.017 to 2.23 Hz. Stimulus-response data were quite linear for any given condition and amplitude. However, overall behavior in normal subjects was nonlinear because gain decreased and phase functions sometimes changed with increasing stimulus amplitude. "Sensory channel reweighting" could account for this nonlinear behavior with subjects showing increasing reliance on vestibular cues as stimulus amplitudes increased. VL subjects could not perform this reweighting, and their stimulus-response behavior remained quite linear. Transfer function curve fits based on a simple feedback control model provided estimates of postural stiffness, damping, and feedback time delay. There were only small changes in these parameters with increasing visual stimulus amplitude. However, stiffness increased as much as 60% with increasing support surface amplitude. To maintain postural stability and avoid resonant behavior, an

  2. 缓控释肥质量快速检测方法探讨%Discussion on rapid quality detection method for slow/controlled release fertilizers

    Institute of Scientific and Technical Information of China (English)

    陈剑秋; 葛雨明; 孙德芳; 王丽萍; 张民

    2012-01-01

    Based on nutrient release testing method for quality detection experiment, the difference between of slow/controlled release fertilizers standard testing method and rapid is studied. The results show that error range between rapid method and standard method is from 2.7% to 8.3% for CRF1, CRF2, CRF3 and CRF4, which completely meet the demand of national standard of GB/T 23348--2009 about error range (25%); For the products (CRF5 to CRF16) with the production conditions changed such as envelope materials, additives and spraying temperature, the evaluation of slow/controlled release fertilizers is not reliable with the original prediction equation; So one prediction equation can't be used to rapidly and accurately detect every slow/controlled release fertilizer.%通过缓控释肥养分释放试验,研究了缓控释肥标准检测方法与快速测定方法的差异。结果表明:供试CRF1至CRF4样品快速测定方法与标准方法误差范围为2.7%~8-3%,完全满足GB/T23348--2009养分释放期允许误差范围25%的要求;在改变包膜材料、添加剂和喷涂温度条件下,制成的CRF5至CRF16样品采用快速测定方法用原有预测方程预测养分释放期可靠性差,表明一个预测方程不能快速准确评价所有缓控释肥。

  3. Application of a hyaluronic acid gel after intrauterine surgery may improve spontaneous fertility: a randomized controlled trial in New Zealand White rabbits.

    Directory of Open Access Journals (Sweden)

    Stephanie Huberlant

    Full Text Available Intrauterine adhesions (IUAs are the most common complication after hysteroscopy in patients of reproductive age. Intra-abdominal anti-adhesion gel reduces the incidence of adhesions, but effects on fertility after uterine surgery are not known. The objective of our work was to evaluate the effect of intrauterine anti-adhesion gel on spontaneous fertility after repeated intrauterine surgery with induced experimental synechiae in the rabbit model.Twenty New Zealand White rabbits underwent a double uterine curettage 10 days apart and were randomized into two groups. Each rabbit served as its own control: one uterine tube was the treatment group (A, the second uterine tube was the control group (B to avoid bias through other causes of infertility. Group A received a post curettage intrauterine instillation of anti-adhesion gel whereas group B, the control group, underwent curettage without instillation of the gel. After a recovery period, the rabbits were mated. An abdominal ultrasound performed 21 days after mating allowed us to diagnose pregnancy and quantify the number of viable fetuses.There was a significant difference in total fetuses in favor of group A, with an average of 3.7 (range, 0-9 total fetuses per tube against 2.1 (0-7 in group B (p = .04. The number of viable fetuses shows a trend in favor of group A, with an average of 3.4 (0-7 viable fetuses per tube against 1.9 (0-6 viable fetuses per tube in group B (p = .05.The use of immediate postoperative anti-adhesion gel improved fertility in an animal model after intrauterine surgery likely to cause uterine synechiae. This experimental model will permit comparison of different anti-adhesion solutions, including assessment of their tolerance and potential mucosal toxicity on embryonic development.

  4. Reproduction (II): Human Control of Reproductive Processes

    Science.gov (United States)

    Jost, Alfred

    1970-01-01

    Describes methods of intervening in reproduction of animals and humans (artificial insemination, contraception, ovular and blastodisc transplants, pre selection of sex, cloning) and discusses the social implications of their use with humans. (AL)

  5. Reproduction (II): Human Control of Reproductive Processes

    Science.gov (United States)

    Jost, Alfred

    1970-01-01

    Describes methods of intervening in reproduction of animals and humans (artificial insemination, contraception, ovular and blastodisc transplants, pre selection of sex, cloning) and discusses the social implications of their use with humans. (AL)

  6. 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

  7. Translational neuroendocrinology: control of human growth.

    Science.gov (United States)

    Clayton, P E; Gill, M S; Tillmann, V; Westwood, M

    2014-06-01

    Human growth is driven by both basic cell processes as well as hormones, in particular the growth hormone (GH)-insulin-like growth factor (IGF)-1 axis. Understanding how these mechanisms are coordinated is not only critical to achieving a normal growth rate, but also to recognising potential new causes of disordered growth and how they might be treated. We have demonstrated in healthy children that height is gained by periods of rapid growth interspersed by periods of very slow growth or even stasis. We have also shown that a lower order organism, Caenorhabditis elegans, grows in a similar manner. By contrast, secretion of GH from somatotrophs occurs on a daily basis in discrete pulses over a 24-h period. We have used the measurement of GH in urine as a surrogate marker of GH secretion to show that there are rhythms of GH output with frequencies of several days. We then assessed which attributes of these GH profiles were related to growth and found that disorderliness in the GH profile (as measured by approximate entropy) was related to better growth rate. This feature was then tested in the dwarf rat using different GH regimens to introduce variation into the administration of daily GH injections. Better long bone growth was associated with week-to-week or even random dose variation compared to the same amount of GH delivered as a standard daily dose. Understanding the control of growth has implications in clinical practice for modelling GH treatment regimens based on physiological principles.

  8. Study on Controlled Release Nitrogen Fertilizer Application Technique for Spring Maize%春玉米控释氮肥施用技术研究

    Institute of Scientific and Technical Information of China (English)

    谢佳贵; 尹彩侠; 张路; 侯云鹏; 秦裕波; 王立春

    2009-01-01

    不同控释氮肥田间试验结果表明,控释氮肥与普通氮肥相比不仅能提高春玉米子粒产量,而且能提高玉米子粒中粗脂肪含量.春玉米的适宜施N量为150 kg/hm~2.控释氮肥与普通氮肥混合施用可显著提高春玉米产量,最佳混配比例为50%控释尿素+50%普通尿素.%Field experiment showed that controlled release N fertilizer could not only increase spring maize yield but also increase its crude fat content, and the appropriate fertilization rate was N 150 kg/ha for spring maize. Mixed application of controlled release N and common N could increase maize yield obviously, and the optimum mixed proportion was 50% controlled release urea + 50% common urea.

  9. Biodegradation of a biochar-modified waterborne polyacrylate membrane coating for controlled-release fertilizer and its effects on soil bacterial community profiles.

    Science.gov (United States)

    Zhou, Zijun; Du, Changwen; Li, Ting; Shen, Yazhen; Zeng, Yin; Du, Jie; Zhou, Jianmin

    2015-06-01

    Biochar-modified polyacrylate-like polymers are promising waterborne polymer-based membrane coatings for controlled-release fertilizers. However, the effect of these membrane polymers on paddy soil is unknown. A soil incubation experiment was conducted using Fourier transform infrared photoacoustic spectroscopy to monitor the changes in the polymer-coated membranes in paddy soil, and Biolog EcoPlates and polymerase chain reaction-denaturing gradient gel electrophoresis were used to detect the effects of the membranes on soil bacterial community profiles. Compared to unmodified membranes, the biodegradation rate of the biochar-modified membrane was slower, and the membrane was more intact, which improved and guaranteed the controlled release of nutrients. Compared to the soil without membranes, the biochar-modified membranes, as well as unmodified ones, showed no significant impacts on the composition diversity of soil dominant bacterial community. The activity and functional diversity of soil culturable microbial community during the early stage of incubation were reduced by biochar-modified membranes due to the release of small amount of soluble organic materials but were both recovered in the 12(th) month of the incubation period. Therefore, the biochar-modified waterborne polyacrylate was environmentally friendly, demonstrating its potential both in the development of coated controlled-release fertilizers and in the utilization of crop residue.

  10. The effect of bovine viral diarrhoea virus on fertility in dairy cows: two case-control studies in the province of Styria, Austria.

    Science.gov (United States)

    Burgstaller, Johann; Obritzhauser, Walter; Kuchling, Sabrina; Kopacka, Ian; Pinior, Beate; Köfer, Josef

    2016-01-01

    Bovine viral diarrhoea (BVD) leads to substantial economic losses in beef and dairy herds worldwide. Two case-control studies were carried out using production data from 1996 to 2012 to analyse the impact of BVD virus (BVDV) on fertility in dairy herds in the province of Styria during an eradication programme. In study 1, herds in which at least one persistently BVDV-infected (PI) animal was detected (case herds) were compared to a group of control herds proven free from BVDV infection (contro herds). In study 2, within BVD infected herds the period during which P animals were present (exposed period) was compared to the period after successful BVD eradication (unexposed period). Calving interval (CAl) and the probability of a first service conception (FSC) were used as indicators in a mixed regression model to investigate the impact of BVD on reproductive performance. The model results indicated that BVD had a significant influence on CAl and FSC. Cows from control herds were 1.1 times more likely to conceive at first service compared to cows from case herds and cows served during the BVDV unexposed period were 1.3 times more likely to conceive at first service than those inseminated during the exposed period. In BVD-infected herds the CAI averaged seven days shorter in unexposed periods than in exposed periods. Besides BVD the animal breed and the parity substantially impact the analysed fertility indicators.

  11. 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

    . RESULTS: A 46,XY boy presented at birth with severe undervirilization of the external genitalia. Steroid profiling showed low steroid production for mineralocorticoids, glucocorticoids and sex steroids with typical precursor metabolites for HSD3B2 deficiency. The genetic analysis of the HSD3B2 gene...... 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...... deficiency due to the c.687del27 deletion does not express the defective protein. This patient is unlikely to be fertile and his risk for gonadal malignancy is low. Further studies are needed to obtain firm knowledge on malignancy risk for gonads harboring defects of androgen biosynthesis....

  12. Impact of air pollution on fertility: a systematic review.

    Science.gov (United States)

    Frutos, Víctor; González-Comadrán, Mireia; Solà, Ivan; Jacquemin, Benedicte; Carreras, Ramón; Checa Vizcaíno, Miguel A

    2015-01-01

    Air pollution has gained considerable interest because of the multiple adverse effects reported on human health, although its impact on fertility remains unclear. A systematic search was performed to evaluate the impact of air pollutants on fertility. Controlled trials and observational studies assessing animal model and epidemiological model were included. Occupational exposure and semen quality studies were not considered. Outcomes of interest included live birth, miscarriage, clinical pregnancy, implantation, and embryo quality. Ten studies were included and divided into two groups: animal studies and human epidemiological studies including the general population as well as women undergoing in vitro fertilization and embryo transfer (IVF/ET). Results from this systematic review suggest a significant impact of air pollution on miscarriage and clinical pregnancy rates in the general population, whereas among subfertile patients certain air pollutants seem to exert a greater impact on fertility outcomes, including miscarriage and live birth rates. Besides, studies in mammals observed a clear detrimental effect on fertility outcomes associated to air pollutants at high concentration. The lack of prospective studies evaluating the effect of air pollution exposure in terms of live birth constitutes an important limitation in this review. Thus, further studies are needed to confirm these findings.

  13. A grounded theory approach to understand the process of decision making on fertility control methods in urban society of Mashhad, Iran.

    Science.gov (United States)

    Roudsari, Robab Latifnejad; Khadivzadeh, Talat; Bahrami, Masoud

    2013-09-01

    More than 30% of pregnancies in Iran are unintended and most of them happen among the women who use various contraceptive methods. Results of Integrated Monitoring and Evaluation System (IMES) showed that the rate of innovative contraceptive use in Mashhad has been 41.5%-57% in different urban areas. This study was conducted to explore the process of making decision toward using family planning methods in women of reproductive age in urban society of Mashhad, Iran. In this grounded theory study, semi-structured interviews were conducted with 45 purposefully selected participants including 28 women and 17 key informants including family health providers and managers, and participants' mothers and husbands, who lived in urban society of Mashhad, Iran, in 2011-2012. Participants' recruitment continued until data saturation occurred. Data were analyzed using Strauss and Corbin's mode of analysis through constant comparative method, applying levels of open, axial, and selective coding with MAXqda software. Study rigor was confirmed through prolonged engagement, member check, expert debriefing, and thick description of the data. The core category of "caring the comprehensive health of my family," which emerged from the data, described the process of couples' decision making toward using family planning methods in this study. Other developed categories which were presented into a theoretical scheme consisted of 1) shaping the ideas of fertility control, 2) developing cognition about the fertility control methods, 3) appraising available choices and choosing the most appropriate one, 4) managing the course of using methods, and 5) realizing the fertility intentions. It is important that family planning providers understand the motivations, perceptions, and knowledge of women about contraceptive methods in their contextual situation, which illustrates their mode of interaction in the arenas of family planning decision making.

  14. A highly homozygous and parthenogenetic human embryonic stem cell line derived from a one-pronuclear oocyte following in vitro fertilization procedure

    Institute of Scientific and Technical Information of China (English)

    Ge Lin; Qi OuYang; Xiaoying Zhou; Yifan Gu; Ding Yuan; Wen Li; Gang Liu; Tiancheng Liu; Guanexiu Lu

    2007-01-01

    Homozygous human embryonic stem cells (hESCs) are thought to be better cell sources for hESC banking because their human leukocyte antigen (HLA) haplotype would strongly increase the degree of matching for certain populations with relatively smaller cohorts of cell lines. Homozygous hESCs can be generated from parthenogenetic embryos, but only heterozygous hESCs have been established using the current strategy to artificially activate the oocyte without second polar body extrusion. Here we report the first successful derivation of a human homozygous ESC line (chHES-32) from a one-pronuclear oocyte following routine in vitro fertilization treatment. cAHES-32 cells express common markers and genes with normal hESCs. They have been propagated in an undifferentiated state for more than a year (>P50) and have maintained a stable karyotype of 46, XX. When differentiated in vivo and in vitro, c/zHES-32 cells can form derivatives from all three embryonic germ layers. The almost undetectable expression of five paternally expressed imprinted genes and their HLA genotype identical to the oocyte donor indicated their parthenogenetic origin. Using genome-wide single-nucleotide polymorphism analysis and DNA fingerprinting, the homozygosity of c/zHES-32 cells was further confirmed. The results indicated that 'unwanted' one-pronuclear oocytes might be a potential source for human homozygous and parthenogenetic ESCs, and suggested an alternative strategy for obtaining homozygous hESC lines from parthenogenetic haploid oocytes.

  15. Birth after human chorionic gonadotropin-primed oocyte in vitro maturation and fertilization with testicular sperm in a normo-ovulatory patient

    Directory of Open Access Journals (Sweden)

    Claudia González-Ortega

    2016-01-01

    Full Text Available In this report, we present a case of in vitro maturation (IVM with surgical retrieved testicular sperm in a normo-ovulatory female. Human chorionic gonadotropin-primed IVM, testicular biopsy for sperm retrieval and intracytoplasmic sperm injection with fresh sperm were performed. Fourteen cumulus-oocyte complexes were obtained in germinal vesicle or metaphase I stage, eight oocytes reached metaphase II, seven presumptive zygotes were obtained, and three cleavage stages embryos in day 2 were transferred producing a singleton pregnancy. A single healthy newborn was obtained. Our results suggest that IVM may be an alternative for in vitro fertilization in normo-ovulatory women even if surgical retrieval of sperm is needed. Further research is required to depict contributing factors to the success of IVM in indications different from polycystic ovaries syndrome and the role of male gamete.

  16. Birth after human chorionic gonadotropin-primed oocyte in vitro maturation and fertilization with testicular sperm in a normo-ovulatory patient

    Science.gov (United States)

    González-Ortega, Claudia; Piña-Aguilar, Raul Eduardo; Cancino-Villareal, Patricia; Gutiérrez-Gutiérrez, Antonio Martin

    2016-01-01

    In this report, we present a case of in vitro maturation (IVM) with surgical retrieved testicular sperm in a normo-ovulatory female. Human chorionic gonadotropin-primed IVM, testicular biopsy for sperm retrieval and intracytoplasmic sperm injection with fresh sperm were performed. Fourteen cumulus-oocyte complexes were obtained in germinal vesicle or metaphase I stage, eight oocytes reached metaphase II, seven presumptive zygotes were obtained, and three cleavage stages embryos in day 2 were transferred producing a singleton pregnancy. A single healthy newborn was obtained. Our results suggest that IVM may be an alternative for in vitro fertilization in normo-ovulatory women even if surgical retrieval of sperm is needed. Further research is required to depict contributing factors to the success of IVM in indications different from polycystic ovaries syndrome and the role of male gamete. PMID:27803591

  17. Effect Research of Controlled Release Special Fertilizer on Rice in Qing'an County%控释专用肥在庆安县水稻上的应用效果研究

    Institute of Scientific and Technical Information of China (English)

    孙磊

    2011-01-01

    The application effect of controlled release special fertilizer on rice-production in Qing'an county was carried out using Songjing No. 9. The result showed that compared to the equal nutrition of common compound fertilizer and high nitrogen fertilizer, the controlled release special fertilizer could increase the rice yield by 23.90% and 15.11%. The treatment 4, which decreasing the amount of controlled release special fertilizer by 30 %,could increase yield by 4.62 % compared with the common fertilizer.%为探索控释专用肥在黑龙江省对水稻生长及产量的影响,以松粳9号为试验材料,对控释肥在庆安县水稻生产上的应用效果进行了研究。结果表明:控释专用肥与等养分普通复合肥和常规高氮复合肥比较,可使水稻增产23.90%和15.11%。处理4在减少控释专用肥施用量30%的情况下,比常规施肥增产4.62%。

  18. Design and Experiment on Control System of Self-Propelled Variable-Rate Fertilizer%液压变量施肥控制系统设计与试验

    Institute of Scientific and Technical Information of China (English)

    陈书法; 赵真; 封成龙; 杨进

    2012-01-01

    为解决现有水田撒肥机械存在肥量调节控制技术落后、不能适应变量作业工作要求等问题,设计了一种变量撒肥控制系统.通过分析国内外变量施肥技术研究情况,概述了变量撒肥机总体结构和工作原理,研究了控制内容和控制策略,确定了以AT89C51单片机作为主控制核心元件的计算机控制系统,进行软硬件设计和系统集成.通过场地和田间撒肥试验表明,撒肥机作业效率达到6 hm2/h,施肥量偏差小于5%,排肥量稳定性变异系数仅为6.2%,撒肥机工作性能和控制系统设计满足水田变量撒肥工作要求.%In order to solve the problem, of backward manure regulation control technology which was not suitable for variable -rate fertilization needs of paddy fertilizing machine,a variable -rate fertilization control system was designed.Based on the domestic and foreign research situations of the variable—rate fertilizing technology, the overall structure and working mechanism of the variable-rate fertilizing machine were described,and control content and strategy were studied, AT89C51single chip was used as a core control element in the control system, hardware and software were designed, and control system was integrated. The variable—rate fertilizing experiment in space and paddy field shows that the working efficiency is up to 6hm2/h, the fertilizing error is less than 5%, and the fertilizing stability variation coefficient is only 6.2%, so the working performance and control system design of the fertilizer is suitable for spreading the fertilizer invariable rate widely and efficiently in paddy field.

  19. Incidence of Y-chromosome microdeletions in children whose fathers underwent vasectomy reversal or in vitro fertilization with epididymal sperm aspiration: a case-control study.

    Science.gov (United States)

    Ghirelli-Filho, Milton; Marchi, Patricia Leme de; Mafra, Fernanda Abani; Cavalcanti, Viviane; Christofolini, Denise Maria; Barbosa, Caio Parente; Bianco, Bianca; Glina, Sidney

    2016-01-01

    To evaluate the incidence of Y-chromosome microdeletions in individuals born from vasectomized fathers who underwent vasectomy reversal or in vitro fertilization with sperm retrieval by epididymal aspiration (percutaneous epididymal sperm aspiration). A case-control study comprising male children of couples in which the man had been previously vasectomized and chose vasectomy reversal (n=31) or in vitro fertilization with sperm retrieval by percutaneous epididymal sperm aspiration (n=30) to conceive new children, and a Control Group of male children of fertile men who had programmed vasectomies (n=60). Y-chromosome microdeletions research was performed by polymerase chain reaction on fathers and children, evaluating 20 regions of the chromosome. The results showed no Y-chromosome microdeletions in any of the studied subjects. The incidence of Y-chromosome microdeletions in individuals born from vasectomized fathers who underwent vasectomy reversal or in vitro fertilization with spermatozoa recovered by percutaneous epididymal sperm aspiration did not differ between the groups, and there was no difference between control subjects born from natural pregnancies or population incidence in fertile men. We found no association considering microdeletions in the azoospermia factor region of the Y chromosome and assisted reproduction. We also found no correlation between these Y-chromosome microdeletions and vasectomies, which suggests that the assisted reproduction techniques do not increase the incidence of Y-chromosome microdeletions. Avaliar a incidência de microdeleções do cromossomo Y em indivíduos nascidos de pais vasectomizados submetidos à reversão de vasectomia ou fertilização in vitro com recuperação de espermatozoides por aspiração do epidídimo (aspiração percutânea de espermatozoides do epidídimo). Estudo caso-controle que compreende crianças do sexo masculino de casais em que o homem havia sido previamente vasectomizado e escolheu revers

  20. Adaptive Regulation of Testis Gene Expression and Control of Male Fertility by the Drosophila Harpin RNA Pathway

    Science.gov (United States)

    Wen, Jiayu; Duan, Hong; Bejarano, Fernando; Okamura, Katsutomo; Fabian, Lacramioara; Brill, Julie A.; Bortolamiol-Becet, Diane; Martin, Raquel; Ruby, J. Graham; Lai, Eric C.

    2014-01-01

    SUMMARY Although endogenous siRNAs (endo-siRNAs) have been described in many species, still little is known about their endogenous utility. Here, we show that Drosophila hairpin RNAs (hpRNAs) generate an endo-siRNA class with predominant expression in testes. Although hpRNAs are universally recently evolved, we identify highly complementary protein-coding targets for all hpRNAs. Importantly, we find broad evidence for evolutionary divergences that preferentially maintain compensatory pairing between hpRNAs and targets, serving as first evidence for adaptive selection for siRNA-mediated target regulation in metazoans. We demonstrate organismal impact of hpRNA activity, since knockout of hpRNA1 derepresses its target ATP synthase-β in testes and compromises spermatogenesis and male fertility. Moreover, we reveal surprising male-specific impact of RNAi factors on germ cell development and fertility, consistent with testis-directed function of the hpRNA pathway. Finally, the collected hpRNA loci chronicle an evolutionary timeline that reflects their origins from prospective target genes, mirroring a strategy described for plant miRNAs. PMID:25544562

  1. 控释肥对西瓜生长发育的影响%Effects of Controlled-release Fertilizer on Growth and Development of Watermelon

    Institute of Scientific and Technical Information of China (English)

    魏元秀; 井大炜; 刘春生

    2011-01-01

    Taking the watermelon Heitong K-8 as meterial,the field experiment was conducted to study effect of controlled-release fertilizer on growth period,plant growth and yield of watermelon.The results showed that controlled-release fertilizer could promote wat%以黑彤K-8西瓜为试验材料,用田间小区试验的方法研究了控释肥对西瓜生育期、植株生长及产量的影响。结果表明,控释肥能促进西瓜早熟3~6 d;相对于习惯施肥,控释肥对植株的生长也有明显的作用;而且对西瓜的产量具有显著的提高作用,在等养分施用情况下与习惯施肥相比,增产幅度为22.32%,而且在减少20%养分用量的情况下,增产幅度仍可达到10.60%;等量控释肥、减量控释肥、减氮控释肥处理的肥料生产率分别为习惯施肥处理的2.28、2.01、1.32倍。

  2. 控失氮肥技术应用及发展总结%Use of Technology for Leach-Control Nitrogenous Fertilizers and Development Summary

    Institute of Scientific and Technical Information of China (English)

    薛宏光; 黄滨; 徐文峰; 李刚

    2013-01-01

    控失氮肥是在对原有高塔造粒装置进行技术升级改造的基础上,将粉状氯化铵或硫酸铵及尿液与可降低其溶解性或改变其流失特性的化肥养分控失剂充分混合后制备的无膜型缓释脲铵氮肥,适合于大田作物.概述了控失氮肥的形成机理、技术路线及创新点、产品特点及质量标准,并就存在的问题提出了今后的努力方向.%On the basis of the original high-tower prilling unit renovated with technological upgrade, powdery ammonium chloride or ammonium sulfate and melted urea are intimately mixed with nutrient leach-control agents able to reduce the solubility or alter the leach properties, to prepare filmless slow-release urea-ammonium nitrogenous fertilizers, suitable for field crops. An outline is given of the formation mechanism of leach-control nitrogenous fertilizers, technological routes and innovation point, product characteristics and quality standards, and the direction for further efforts for solving the remaining problems.

  3. 缓控释肥料氮素释放的动力学%Kinetics of Slow Controlled Nitrogen Release from Fertilizer

    Institute of Scientific and Technical Information of China (English)

    陈可可; 张保林; 侯翠红

    2012-01-01

    利用水浸提法研究了国内外6种缓控释肥料在不同温度下的氮素释放特性,并研究了其氮素释放过程的动力学.不同温度下缓控释肥料的氮素累积释放率表明,供试的6种肥料在静水中的氮素累积释放率均随着温度的升高而增大,且温度越高,氮素累积释放率增加的越快.引入一级反应动力学方程,氮素释放速率常数k和氮素释放过程的活化能Ea结果表明,在6种供试肥料中,氮素释放过程对温度最敏感的是缓溶复混肥料(zdLuxe-02),受温度影响最小的为微晶聚合硫包衣尿素(hf-01).%The nitrogen release characteristics of 6 slow-controlled release fertilizers produced by different technologies were studied using water extraction method at different temperature. The results indicated that the cumulative release amount of nitrogen of the 6 slow-controlled release fertilizers increased with the increase of temperature, the higher the temperature, the bigger the cumulative release rate of nitrogen. A first-order kinetic rate expression was introduced. The results of kinetics showed that, with the increase of temperature, the rate constant of nitrogen release (k) increased and the activation energy of nitrogen release (Ea) decreased. Among all the 6 fertilizers, slow-dissolving compound fertilizers (zdLuxe-02) was the most sensitive one to the temperature, whereas Microcrystal-poly-sulfur coated urea (hf-01) was the least sensitive one to the temperature.

  4. Contraceptive vaccines for the humane control of community cat populations.

    Science.gov (United States)

    Levy, Julie K

    2011-07-01

    Free-roaming unowned stray and feral cats exist throughout the world, creating concerns regarding their welfare as well as their impact on the environment and 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 non-lethal population control method but is limited in scope because of expense and logistical impediments. Immunocontraception has the potential to be a more practical and cost-effective method of control. 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. 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. 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 multiyear contraception following a single dose in a high proportion of treated cats.

  5. 聚合物包膜缓/控释肥料的研究进展%Research Progress of Polymer Coated Slow/Controlled Release Fertilizer

    Institute of Scientific and Technical Information of China (English)

    范本荣; 沈玉文; 江丽华; 林海涛; 刘兆辉

    2011-01-01

    The research on coated slow/controlled release fertilizers (CRFs) have become hot in domestic and overseas. Especially the polymer coated CRFs gradually occupied the dominant position of market. In order to help people understand polymer coated fertilizer deeply and apply them correctly, the contents were summarized as follows: different types of polymer coated materials, the developing status of polymer coated fertilizers at home and abroad, nutrient release characteristics of CRFs, evaluation methods for nutrient release characteristics and developing prospect of polymer coated CRFs.%缓/控释肥料是近年来国内外的研究热点,尤其是以聚合物为主要包膜材料的缓/控释肥逐渐占据了缓/控释肥料市场的主导地位.为了使人们更为全面地了解聚合物包膜缓/控释肥料并正确的加以应用,我们系统总结了如下内容:不同类型的聚合物包膜材料;聚合物包膜缓/控释肥在国内外的发展状况;聚合物包膜缓/控释肥料的养分释放特征;针对其养分释放特征的评价方法;并展望了聚合物包膜缓/控释肥料的发展前景.

  6. 安徽沿江棉区控失型化肥施用技术研究%Research on the Application Technology of Controlled-release Chemical Fertilizer in the Cotton Area along Yangtze River in Anhui Province

    Institute of Scientific and Technical Information of China (English)

    余立祥; 邱冠男; 吴跃进

    2009-01-01

    [目的]研究控失肥在棉区的施用技术,验证控失肥的"控失"效果及其经济效益.[方法]以当地主要推广的抗虫棉品种为供试作物,通过在安徽省沿江棉田进行施肥试验研究了控失肥不同施用方式对棉花产量和效益的影响.[结果]与一次基施全部控失肥相比,将控失肥分3次施用使棉花产量增加了240 kg/hm~2,棉农的净收入增加了156元/hm~2;将控失肥基施,后期追施速效化肥使棉花产量增加了7.04%,棉农的净收入增加了833.4元/hm~2.施用减氮20%的控失肥的棉花的现蕾期提前了6 d,开花期提前了7 d,吐絮期提前了8 d,生育期短了8 d.与施用普通氮肥的棉花相比,施用控失氮肥的棉花的秋桃增加幅度为22.29%~36.31%,皮棉产量增加了27.78%.[结论]该研究为在安徽沿江棉区推广应用控失肥提供了科学依据.%[Objective] The purpose was to research the application technology of controlled-release fertilizer in cotton area and validate its controlled-release effect and economic benefit. [Method] With the insect-resistant cotton varieties mainly popularized in the local place as tested crops, the effect of different application methods of controlled-release fertilizer on the yield and benefit of cotton was researched through carrying out fertilization experiment in the cotton fields along Yangtze River in Anhui Province. [Result] Compared with applying all the controlled-release fertilizer as base fertilizer at the first fertilization, when the controlled-release fertilizer was applied 3 times separately, the cotton yield was increased for 240 kg/hm~2 and the net income of cotton farmers was increased for 156 yuan/hm~2; when the controlled-release fertilizer was applied as base fertilizer and the fast-available chemical fertilizer was dressed in the anaphase, the cotton yield was increased by 7.04% and the net income of cotton farmers was increased for 833.4 yuan/hm~2. The squaring period of cottons applied

  7. Improving patient-centeredness of fertility care using a multifaceted approach: study protocol for a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Huppelschoten Aleida G

    2012-09-01

    Full Text Available Abstract Background Beside traditional outcomes of safety and (cost-effectiveness, the Institute of Medicine states patient-centeredness as an independent outcome indicator to evaluate the quality of healthcare. Providing patient-centered care is important because patients want to be heard for their ideas and concerns. Healthcare areas associated with high emotions and intensive treatment periods could especially benefit from patient-centered care. How care can become optimally improved in patient-centeredness is unknown. Therefore, we will conduct a study in the context of Dutch fertility care to determine the effects of a multifaceted approach on patient-centeredness, patients’ quality of life (QoL and levels of distress. Our aims are to investigate the effectiveness of a multifaceted approach and to identify determinants of a change in the level of patient-centeredness, patients’ QoL and distress levels. This paper presents the study protocol. Methods/Design In a cluster-randomized trial in 32 Dutch fertility clinics the effects of a multifaceted approach will be determined on the level of patient-centeredness (Patient-centredness Questionnaire – Infertility, patients’ QoL (FertiQoL and levels of distress (SCREENIVF. The multifaceted approach includes audit and feedback, educational outreach visits and patient-mediated interventions. Potential determinants of a change in patient-centeredness, patients’ QoL and levels of distress will be collected by an addendum to the patients’ questionnaire and a professionals’ questionnaire. The latter includes the Organizational Culture Assessment Instrument about the clinic’s culture as a possible determinant of an increase in patient-centered care. Discussion The study is expected to yield important new evidence about the effects of a multifaceted approach on levels of patient-centeredness, patients’ QoL and distress in fertility care. Furthermore, determinants associated with a change

  8. Control of superoxide and nitric oxide formation during human sperm capacitation.

    Science.gov (United States)

    de Lamirande, Eve; Lamothe, Geneviève; Villemure, Michèle

    2009-05-15

    We studied the modulation of superoxide anion (O(2).(-)) and nitric oxide (NO.) generation during human sperm capacitation (changes needed for the acquisition of fertility). The production of NO. (diaminofluorescein-2 fluorescence assay), but not that of O(2).(-) (luminescence assay), related to sperm capacitation was blocked by inhibitors of protein kinase C, Akt, protein tyrosine kinase, etc., but not by those of protein kinase A. Extracellular calcium (Ca(2+)) controlled O(2).(-) synthesis but extra- and intracellular Ca(2+) regulated NO. formation. Zinc inhibited capacitation and formation of O(2).(-) and NO.. Zinc chelators (TPEN and EDTA) and sulfhydryl-targeted compounds (diamide and N-ethylmaleimide) stimulated capacitation and formation of O(2).(-) and NO.; superoxide dismutase (SOD) and nitric oxide synthase inhibitor (L-NMMA) prevented these events. Diphenyliodonium (flavoenzyme inhibitor) blocked capacitation and related O(2).(-) synthesis but promoted NO. formation, an effect canceled by SOD and L-NMMA. NADPH induced capacitation and NO. (but not O(2).(-)) synthesis and these events were blocked by L-NMMA and not by SOD. Integration of these data on O(2).(-) and NO. production during capacitation reinforces the concept that a complex, but flexible, network of factors is involved and probably is associated with rescue mechanisms, so that spermatozoa can achieve successful fertilization.

  9. Fuzzy Simulation Human Intelligent Control System Design on Gyratory Breaker

    Institute of Scientific and Technical Information of China (English)

    Wen,Ruchun; Zhao,Shuling; Zhu,Jianwu; Wang,Xiaoyan

    2005-01-01

    In order to deal with the complex process that incurs serious time delay, enormous inertia and nonlinear problems,fuzzy simulation human intelligent control algorithm rules are established. The fuzzy simulation human intelligent controller and the hardware with the single-chip microcomputer are designed and the anti-interference measures to the whole system are provided.

  10. Uniquely Human Self-Control Begins at School Age

    Science.gov (United States)

    Herrmann, Esther; Misch, Antonia; Hernandez-Lloreda, Victoria; Tomasello, Michael

    2015-01-01

    Human beings have remarkable skills of self-control, but the evolutionary origins of these skills are unknown. Here we compare children at 3 and 6 years of age with one of humans' two nearest relatives, chimpanzees, on a battery of reactivity and self-control tasks. Three-year-old children and chimpanzees were very similar in their abilities to…

  11. Uniquely Human Self-Control Begins at School Age

    Science.gov (United States)

    Herrmann, Esther; Misch, Antonia; Hernandez-Lloreda, Victoria; Tomasello, Michael

    2015-01-01

    Human beings have remarkable skills of self-control, but the evolutionary origins of these skills are unknown. Here we compare children at 3 and 6 years of age with one of humans' two nearest relatives, chimpanzees, on a battery of reactivity and self-control tasks. Three-year-old children and chimpanzees were very similar in their abilities to…

  12. Human control of an inverted pendulum: is continuous control necessary? Is intermittent control effective? Is intermittent control physiological?

    Science.gov (United States)

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

    2011-01-15

    Human motor control is often explained in terms of engineering 'servo' theory. Recently, continuous, optimal control using internal models has emerged as a leading paradigm for voluntary movement. However, these engineering paradigms are designed for high band-width, inflexible, consistent systems whereas human control is low bandwidth and flexible using noisy sensors and actuators. By contrast, engineering intermittent control was designed for bandwidth-limited applications. Our general interest is whether intermittent rather than continuous control is generic to human motor control. Currently, it would be assumed that continuous control is the superior and physiologically natural choice for controlling unstable loads, for example as required for maintaining human balance. Using visuo-manual tracking of an unstable load, we show that control using gentle, intermittent taps is entirely natural and effective. The gentle tapping method resulted in slightly superior position control and velocity minimisation, a reduced feedback time delay, greater robustness to changing actuator gain and equal or greater linearity with respect to the external disturbance. Control was possible with a median contact rate of 0.8±0.3 s(-1). However, when optimising position or velocity regulation, a modal contact rate of 2 s(-1) was observed. This modal rate was consistent with insignificant disturbance-joystick coherence beyond 1-2 Hz in both tapping and continuous contact methods. For this load, these results demonstrate a motor control process of serial ballistic trajectories limited to an optimum rate of 2 s(-1). Consistent with theoretical reasoning, our results suggest that intermittent open loop action is a natural consequence of human physiology.

  13. Soil fertility controls soil–atmosphere carbon dioxide and methane fluxes in a tropical landscape converted from lowland forest to rubber and oil palm plantations

    Directory of Open Access Journals (Sweden)

    E. Hassler

    2015-06-01

    Full Text Available Expansion of palm oil and rubber production, for which global demand is increasing, causes rapid deforestation in Sumatra, Indonesia and is expected to continue in the next decades. Our study aimed to (1 quantify changes in soil CO2 and CH4 fluxes with land-use change, and (2 determine their controlling factors. In Jambi Province, Sumatra, we selected two landscapes on heavily weathered soils that differ mainly in texture: loam and clay Acrisol soils. At each landscape, we investigated the reference land uses: forest and secondary forest with regenerating rubber, and the converted land uses: rubber (7–17 years old and oil palm plantations (9–16 years old. We measured soil CO2 and CH4 fluxes monthly from December 2012 to December 2013. Annual soil CO2 fluxes from the reference land uses were correlated with soil fertility: low extractable phosphorus (P coincided with high annual CO2 fluxes from the loam Acrisol soil that had lower fertility than the clay Acrisol soil (P 2 fluxes from the oil palm decreased compared to the other land uses (P 2 fluxes were positively correlated with soil organic carbon (C and negatively correlated with 15N signatures, extractable P and base saturation. This suggests that the reduced soil CO2 fluxes from oil palm was a result of strongly decomposed soil organic matter due to reduced litter input, and possible reduction in C allocation to roots due to improved soil fertility from liming and P fertilization in these plantations. Soil CH4 uptake in the reference land uses was negatively correlated with net nitrogen (N mineralization and soil mineral N, suggesting N limitation of CH4 uptake, and positively correlated with exchangeable aluminum (Al, indicating decrease in methanotrophic activity at high Al saturation. Reduction in soil CH4 uptake in the converted land uses compared to the reference land uses (P 2 and CH4 in a tropical landscape, a mechanism that we were able to detect by conducting this study at the

  14. A case-control study to estimate the effects of acute clinical infection with the Schmallenberg virus on milk yield, fertility and veterinary costs in Swiss dairy herds.

    Science.gov (United States)

    Wüthrich, M; Lechner, I; Aebi, M; Vögtlin, A; Posthaus, H; Schüpbach-Regula, G; Meylan, M

    2016-04-01

    Schmallenberg virus (SBV) was first detected in Switzerland in July 2012 and many Swiss dairy farmers reported acute clinical signs in dairy cattle during the spread of the virus until December 2012. The objectives of the present study were to investigate the effects of an acute infection with SBV on milk yield, fertility and veterinary costs in dairy farms with clinical signs of SBV infection (case farms), and to compare those farms to a matched control group of dairy farms in which cattle did not show clinical signs of SBV infection. Herd size was significantly (pcase farms (33 cows, n=77) than in control farms (25 cows, n=84). Within case herds, 14.8% (median) of the cows showed acute clinical signs. Managers from case farms indicated to have observed a higher abortion rate during the year with SBV (6.5%) than in the previous year (3.7%). Analysis of fertility parameters based on veterinary bills and data from the breeding associations showed no significant differences between case and control farms. The general veterinary costs per cow from July to December 2012 were significantly higher (p=0.02) in case (CHF 19.80; EUR 16.50) than in control farms (CHF 15.90; EUR 13.25). No differences in milk yield were found between groups, but there was a significant decrease in milk production in case farms in the second half year in 2012 compared to the same period in 2011 (pclinical signs (n=461) were treated by a veterinarian. The average calculated loss after SBV infection for a standardized farm was CHF 1606 (EUR 1338), which can be considered as low at the national level, but the losses were subject to great fluctuations between farms, so that individual farms could have very high losses (>CHF 10,000, EUR 8333).

  15. Comparison of Human and Humanoid Robot Control of Upright Stance

    OpenAIRE

    Peterka, Robert J.

    2009-01-01

    There is considerable recent interest in developing humanoid robots. An important substrate for many motor actions in both humans and biped robots is the ability to maintain a statically or dynamically stable posture. Given the success of the human design, one would expect there are lessons to be learned in formulating a postural control mechanism for robots. In this study we limit ourselves to considering the problem of maintaining upright stance. Human stance control is compared to a sugges...

  16. Effects of Controlled-release Fertilizer on Rhizosphere Soil Microoganisms, Soil Fertility and Agronomic Characters of Soybean%控释肥对大豆根际土壤微生物数目、肥力及大豆农艺性状的影响

    Institute of Scientific and Technical Information of China (English)

    孟庆英; 于忠和; 贾会彬; 张春峰; 朱宝国; 王囡囡; 高雪冬

    2011-01-01

    The objective of current study was to investigate the effects of controlled-release fertilizer treatments on rhizosphere soil microorganisms,soil fertility and agronomic characters of soybean. Four fertilizer treatments,including no fertilizer(CK) , conventional fertilizer(CF) ,controlled-release urea(CRU) and controlled-release compound fertilizer(CRF)were adopted. The numbers of bacteria,fungi,actinomycetes of rhizosphere soil at pre-sowing and maturity were determined through colony counting method;the change of rhizosphere soil microorganisms,soil nutrient content,soybean agronomic characters as well as yield components were investigated. Compared with CK and CF,the numbers of bacteria,fungi,actinomycetes as well as soil fertility were obviously increased under CRU and CRF. The effect of CRF was better than CRU in terms of soil bacteria number and soil fertility. CRU and CRF didn't show significant advantage for agronomic characters and yield components of soybean. Compared with conventional fertilizer,controlled-release fertilizer could increase the numbers of soil microoganisms,improve soil fertility and fertilizer efficiency,hence reduce fertilizer pollution on the environment.%采用无肥、常规肥、控释尿素和控释复合肥4种肥料处理,于大豆播种前和成熟期对大豆根际土壤的细菌、真菌、放线菌采用平板计数法进行测定;并对大豆成熟期根际土壤微生物数量变化、土壤养分含量变化及大豆农艺性状及产量相关因素进行分析.结果表明:与无肥和常规肥比较,控释尿素和控释复合肥可明显增加土壤中细菌、真菌及放线菌数目,并且控释复合肥处理的细菌数目、土壤养分含量等项目优于控释尿素处理;在大豆农艺性状及产量相关因素方面,控释尿素及控释复合肥未表现出显著优势.与常规肥相比,施用控释肥可以增加土壤中微生物数量、提高供肥能力,从而提高肥料利用率,减少化肥对环境的污染.

  17. 不同类型玉米控释肥的应用效果研究%Study on Application Effect of Different Types of Controlled-Release Fertilizer on Maize

    Institute of Scientific and Technical Information of China (English)

    王友平; 李宗新; 张书良; 郭建军; 高春华; 张慧; 朱金英

    2014-01-01

    Based on the equal amount of phosphorus and potassium , Ludan 818 was used to study the in-fluence of controlled-release fertilizer on maize yield , soil nutrient contents and fertilizer use efficiency in the application mode of full and 80%nitrogen.The results showed that the application of controlled -release fer-tilizer improved the dry matter accumulation , maize yield and fertilizer use efficiency .It could increase the yield by 17.61%~24.39%and 0.59%~6.38%respectively compared with the CK and conventional fertili-zation .The maize yield was the highest when the controlled -release fertilizer A was full used .But in compre-hensive consider, it was optimum to use the controlled -release fertilizer A at 80%amount (192 kg/hm2).%以鲁单818为供试品种,在磷钾量相等、氮量分别为全量和80%模式下,研究了控释肥对玉米产量、土壤养分含量以及肥料利用效率的影响。结果表明,控释肥处理有助于玉米物质积累,提高玉米的产量和肥料利用率,比CK增产17.61%~24.39%,比习惯施肥增产0.59%~6.38%;全量A控释肥的产量最高,但综合衡量,本试验条件下,以控释肥A 80%施氮量即192 kg/hm2水平最为合理。

  18. Effects of Bag-controlled Slow Release Fertilizer on the Yield and Quality of Crimson Seedless%袋控缓释肥对克瑞森葡萄产量和品质的影响

    Institute of Scientific and Technical Information of China (English)

    孙占育; 郭春会; 刘小菊

    2011-01-01

    采用4个不同施肥处理,通过田间试验,研究了袋控缓释肥时克瑞森葡萄产量和品质的影响.结果表明:袋控缓释肥可提高克瑞森葡萄的产量和品质,产量达到37 257.4 kg.hm-2,比不施肥提高了51.2%,可溶性固形物含量达22.23%,高于其他处理;袋控缓释肥处理提高了叶片N、P、K含量、叶绿素含量及光合速率.袋控缓释肥简单易行,省工节肥,减少污染,有效解决了葡萄施肥中养分的平衡供应问题,是一种理想的施肥方式.%Field trial was conducted to study the effect of the bag-controlled slow release fertilizer on the yield and quality of Crimson seedless by the four treatments. The results showed that bag-controlled slow release fertilizer could improve the yield and quality of Crimson seedless. The yield was 37 257. 4 kg ? Hm~2 by applying the paper-bag-controlled slow release fertilizer, increased by 51. 2% compared with CK. Sugar content reached to 22. 23%, which was better than other treatments. The contents of N, P, K and chlorophyll and photosynthetic rate of the leaves were relatively increased by the bag-controlled slow release fertilizer. It is an ideal way of fertilization that could simply save labor and fertilizer and reduce pollution, which could effective solve the supply of nutrient balance of grape of fertilization.

  19. 作物控效肥效果初步评价%Preliminary Evaluation on Effect of Crops Controlled-Release Fertilizers

    Institute of Scientific and Technical Information of China (English)

    任仕伟; 罗微

    2012-01-01

    采用水浸泡法对5种包膜控效肥(不包括对照)试样的养分溶出率进行了比较测定,测得各种肥料的初期溶出率、微分溶出率分别为,自行研制控效CAF1:1.14、1.78;CAF4:1.59、1.84;CAF5:1.37、1.76;国外肥料FB:1.01、1.24;FZ:1.24、1.27,自行研制的肥料的初期溶出率平均值为1.37,微分溶出率为1.79;国外肥料为1.13、1.25,自行研制的肥料的初期溶出率与微分溶出率分别高于国外肥料,但都达到了国际标准(初期溶出率小于15%、微分溶出率在0.25%~2.5%之间)。同时用土壤淋溶法对自制的2种控效肥和1种进口肥进行了N溶出量的测定,结果表明:控效肥土壤淋溶出量与对照比较为显著,6d内CAF1、CAF5溶出N总量分别为对照的33.3%、36.1%,同时将两种方法所得出的结果进行了综合分析,对控效效果作出初步评价,为作物合理施肥提供参考。%Five kinds of controlled-release fertilizers (except for the CK),coated by organic polymer,were used in this study.The soluble properties of fertilizers were tested and compared in water.The preliminary solubility and differential solubility,are respectively:CAF1:1.14,1.78; CAF4:1.59,1.84; CAF5:1.37,1.76; FB:1.01,1.24; FZ:1.24,1.27.Among the five kinds of controlled-release fertilizers,CAF1,CAF4 and CAF5 were prepared by ourselves,while FB and FZ were imported fertilizers.The average of preliminary solubility of CAF1,CAF4 and CAF5 is 1.37,differential solubility is 1.79.However,the average of preliminary solubility is 1.25.Compared with the latter,the preliminary solubility of the former exceeds 0.26,and the differential solubility exceeds 0.54,but they all reach the international standards——-the preliminary solubility less than 15%,differential solubility is 0.25% to 2.5%.Meanwhile,we determinated the quantity of N release of CAF1,CAF5 and FB by soil dissolution rate method.The total quantity of N release in six days of CAF1 was

  20. Study of Applying Coated Controlled Blend Bulk Fertilizers on Apple%控释BB肥在苹果上的应用研究

    Institute of Scientific and Technical Information of China (English)

    陈琛; 王丽霞; 赵海永; 邵蕾

    2012-01-01

    A field experiment was conducted to study the effects of controlled release fertilizers blended with common fertilizers on yield,quality,and economic benefit of apple in order to provide scientific evidence and technical advice for applying controlled release fertilizers on apple. The result showed that the available nutrient in soil of SF treatment decreased gradually in a growing season. The controlled release fertilizers blended with common fertilizers solved the problem of nutrient's slow release in a short time after being applied and met with the nutrient requirement of plant in a growing season. The application rate of CRF1 was the same as that of SF,but the yield,quality and economic benefit of CRF1 were better than that of SF. The application rate of CRF2 and CRF3 was lower than that of SF, but the yield, quality and economic benefit of CRF2 and CRF3 weren't lower. Considering prompting the palate of fruit,decreasing the application and increasing the economic benefit,the CRF3 was the optimal treatment.%通过田间试验,探讨了施用包膜肥料与普通肥料的控释BB肥对土壤养分和苹果产量、品质、经济效益的影响,以期为控释肥在苹果上合理施用提供依据和技术指导.结果表明,普通肥料由于其速溶性,施肥后土壤速效养分变化曲线在一个生长期内表现为逐渐下降趋势;将控释肥与普通肥料掺混后,既解决了控释肥施用前期养分释放缓慢的问题,又满足了作物整个生长期内养分的需求.施肥量相同的SF与CRF1处理相比较,CRF1处理的苹果产量、品质、经济效益显著高于SF处理;即使减少肥料的施用量,CRF2、CRF3处理的苹果产量、品质、经济效益仍不低于SF处理.从提高果实的口感、减少肥料的投入、增加经济效益的角度考虑,本试验的最佳施肥处理为减氮控释肥CRF3处理.

  1. Comparison of Nutrient Release Characteristics from Coated Controlled/Slow-release Fertilizers%包膜缓/控肥氮释放特性比较研究

    Institute of Scientific and Technical Information of China (English)

    陆乐峰; 王殿武; 李晓欣; 张芮华

    2011-01-01

    [Objective] The study aimed at comparing the characteristics of nutrient release from coated controlled/slow-release fertilizers, so as to provide theoretical reference for improving the farming practice and fertilizer application, reducing pollution in Baiyangdian Lake and the surrounding area. [Method] Soil column leaching method was used to study NH4-N and NO3-N leaching characteristics from five kinds of nitrogen fertilizers including three coated controlled/slow-release fertilizers. [Result] Resin and sulfur coated controlled/slow-release urea decreased NH4-N concentration obviously, controlled NO3-N release in early term of experiment, while increased the content of NH4-N + NO3-N in middlelate periods. Compared with that of common urea, the NH4-N of resin and sulfur coated controlled/slow-release urea decreased by 98.5%,98.7% in early period, 96.5%, 97.4% in middle period, and 59.1%, 81.75% in last period. [Conclusion] Resin and sulfur coated controlled/slow-release urea significantly reduced the NH4-N concentration, effectively controlled the NO3-N release in early stage and increased the supply of NO3-N in last period.%[目的]比较包膜缓/控肥氮释放特性,为改善白洋淀及周边地区农业耕作施肥习惯和减轻白洋淀污染状况提供理论依据.[方法]采用"土柱淋溶法"室内模拟试验,研究了 5种肥料在白洋淀地区土壤中铵态氮和硝态氮释放淋溶情况.[结果]树脂包衣和硫包衣尿素在试验前期淋溶液中铵态氮含量较普通尿素分别减少了98.5%和98.7%,在试验中期分别减少了96.5%和97.4%,在试验后期分别减少了38.7%和76.7%;而硝态氮含量在试验前期较普通尿素分别减少了59.1%和81.7%,在试验中期分别增加了414.7%和40.7%,在试验后期分别增加了1 702.8%和642.3%.[结论]树脂包衣和硫包农尿素明显减少了易挥发的铵态氮含量,有效控制了作物易吸收利用的硝态氮在前期的释放,并增加了在中后期易吸收氮的供应.

  2. 包膜缓/控肥氮释放特性比较研究%Comparison of Nutrient Release Characteristics from Coated controlled/slow-release Fertilizers

    Institute of Scientific and Technical Information of China (English)

    陆乐峰; 王殿武; 李晓欣; 张芮华

    2011-01-01

    [目的]比较包膜缓/控肥氮释放特性,为改善白洋淀及周边地区农业耕作施肥习惯和减轻白洋淀污染状况提供理论依据.[方法]采用“土柱淋溶法”室内模拟试验,研究了5种肥料在白洋淀地区土壤中铵态氮和硝态氮释放淋溶情况.[结果]树脂包衣和硫包衣尿素在试验前期淋溶液中铵态氮含量较普通尿素分别减少了98.5%和98.7%,在试验中期分别减少了96.5%和97.4%,在试验后期分别减少了38.7%和76.7%;而硝态氮含量在试验前期较普通尿素分别减少了59.1%和81.8%,在试验中期分别增加了414.7%和40.7%,在试验后期分别增加了1 702.8%和642.3%.[结论]树脂包衣和硫包衣尿素明显减少了易挥发的铵态氮含量,有效控制了作物易吸收利用的硝态氯在前期的释放,并增加了在中后期易吸收氮的供应.%[Objective ] The study aimed at comparing the characteristics of nutrient release from coated controlled/slow-release fertilizers, so as to provide theoretical reference for improving the farming practice and fertilizer application, reducing pollution in Baiyangdian Lake and the . Surrounding area. [ Method] Soil column leaching method was used to study NH4-N and NO3-N leaching characteristics from five kinds of ni trogen fertilizers including three coated controlled/slow-release fertilizers. [ Result ] Resin and sulfur coated controlled/slow-release urea de creased NH4-N concentration obviously, controlled NO3-N release in early term of experiment, while increased the content of NH4-N + NO3-N in middle-late periods. Compared with that of common urea, the NH4-N of resin and sulfur coated controlled/slow-release urea decreased by 98.5% , 98.7% in early period, 96.5% , 97.4% in middle period, and 59. 1% , 81.8% in last period. [Conclusion] Resin and sulfur coa ted controlled/slow-release urea significantly reduced the NH4-N concentration, effectively controlled the NO3-N release in early

  3. A computer simulation approach to measurement of human control strategy

    Science.gov (United States)

    Green, J.; Davenport, E. L.; Engler, H. F.; Sears, W. E., III

    1982-01-01

    Human control strategy is measured through use of a psychologically-based computer simulation which reflects a broader theory of control behavior. The simulation is called the human operator performance emulator, or HOPE. HOPE was designed to emulate control learning in a one-dimensional preview tracking task and to measure control strategy in that setting. When given a numerical representation of a track and information about current position in relation to that track, HOPE generates positions for a stick controlling the cursor to be moved along the track. In other words, HOPE generates control stick behavior corresponding to that which might be used by a person learning preview tracking.

  4. Determination of Nitrogen, Phosphorus, and Potassium Release Rates of Slow- and Controlled-Release Fertilizers: Single-Laboratory Validation, First Action 2015.15.

    Science.gov (United States)

    Thiex, Nancy

    2016-01-01

    A previously validated method for the determination of nitrogen release patterns of slow- and controlled-release fertilizers (SRFs and CRFs, respectively) was submitted to the Expert Review Panel (ERP) for Fertilizers for consideration of First Action Official Method(SM) status. The ERP evaluated the single-laboratory validation results and recommended the method for First Action Official Method status and provided recommendations for achieving Final Action. The 180 day soil incubation-column leaching technique was demonstrated to be a robust and reliable method for characterizing N release patterns from SRFs and CRFs. The method was reproducible, and the results were only slightly affected by variations in environmental factors such as microbial activity, soil moisture, temperature, and texture. The release of P and K were also studied, but at fewer replications than for N. Optimization experiments on the accelerated 74 h extraction method indicated that temperature was the only factor found to substantially influence nutrient-release rates from the materials studied, and an optimized extraction profile was established as follows: 2 h at 25°C, 2 h at 50°C, 20 h at 55°C, and 50 h at 60°C.

  5. 我国缓/控释肥料的应用效应研究进展%Research Advances on the Use Efficiency of Slow/Controlled Release Fertilizer

    Institute of Scientific and Technical Information of China (English)

    古慧娟; 石元亮; 于阁杰; 王晶

    2011-01-01

    世界缓/控释肥的消耗最逐年增长,越来越多的学者对缓/控释肥的应用效应进行了研究.在前人研究的基础上,从肥料效应、作物效应、环境效应、生物学效应四个方面对缓/控释肥的应用效应作一综述,并提出我国缓/控释肥所存在的问题及展望.%The consumption of the slow/controlled release fertilizer in the world is increasing year after year, and more and more scientists have studied the use efficiency of the slow/controlled release fertilizer. Based on many results of studies, the use efficiency of the slow/controlled release fertilizer were summarized in the paper from four aspects which are fertilizer, crop and environment and biology. The problems of the slow/controlled release fertilizer and further directions were also brought forward.

  6. In vitro fertilization and stem cell harvesting from human embryos: the law and practice in the United States.

    Science.gov (United States)

    Hook, C Christopher

    2010-07-01

    The challenges before science and medicine are these: science must explore the natural world as thoroughly as possible, while still honoring, protecting, serving and preserving the subject of its investigations, and the human beings for whom it is a tool; medicine must confront disease and disability as effectively as possible, while also honoring, protecting, and preserving those beings for whom it serves - all of those beings, not just some, or even most, at the potential expense of others. These goals are challenged by embryo-destructive human embryonic stem cell research. The human embryo is a human being as clearly defined by embryology, and as such should be protected by the codes governing human subject research. However, because of the "potential" benefits offered by pluripotent stem cells, coupled with abortion politics and a very poorly regulated infertility industry, United States governmental advisory commissions and the scientific, medical, and political communities have attempted to define away the humanity of the human embryo, with a few notable exceptions. Because infertility treatments in the United States are poorly regulated, there are large numbers of supernumerary embryos in cryopreservation. However, only a tiny portion of these will ever be potentially available for research, and thus are not a realistic source of the cells necessary to provide treatments to the millions who might benefit from proposed stem cell based therapies. Cloning will not be the answer either, given the millions of women who must be exploited to provide sufficient numbers of eggs to generate the cloned cell lines. Moreover, the disposition decisions parents must make for their extra embryos are often agonizing, and not uncommonly change. The use of supernumerary embryos as a source for human embryonic stem cells is unethical, will never be a sufficient source for the medical treatments expected from stem cell research, and is often a source of great distress for the

  7. In vitro fertilization and stem cell harvesting from human embryos: the law and practice in the United States

    Directory of Open Access Journals (Sweden)

    C. Christopher Hook

    2010-07-01

    Full Text Available The challenges before science and medicine are these: science must explore the natural world as thoroughly as possible, while still honoring, protecting, serving and preserving the subject of its investigations, and the human beings for whom it is a tool; medicine must confront disease and disability as effectively as possible, while also honoring, protecting, and preserving those beings for whom it serves – all of those beings, not just some, or even most, at the potential expense of others. These goals are challenged by embryo-destructive human embryonic stem cell research. The human embryo is a human being as clearly defined by embryology, and as such should be protected by the codes governing human subject research. However, because of the “potential” benefits offered by pluripotent stem cells, coupled with abortion politics and a very poorly regulated infertility industry, United States governmental advisory commissions and the scientific, medical, and political communities have attempted to define away the humanity of the human embryo, witha few notable exceptions. Because infertility treatments in the United States are poorly regulated, there are large numbersof supernumerary embryos in cryopreservation. However, only a tiny portion of these will ever be potentially available for research, and thus are not a realistic source of the cells necessary to provide treatments to the millions who might benefit from proposed stem cell based therapies. Cloning willnot be the answer either, given the millions of women who must be exploited to provide sufficient numbers of eggs to generate the cloned cell lines. Moreover, the disposition decisions parents must make for their extra embryos are often agonizing, and not uncommonly change.The use of supernumerary embryos as a source for human embryonic stem cells is unethical, will never be a sufficient source for the medical treatments expected from stem cell research, and is often a source of

  8. Adaptive Human Control Gains During Precision Grip

    Directory of Open Access Journals (Sweden)

    Erik D. Engeberg

    2013-03-01

    Full Text Available Eight human test subjects attempted to track a desired position trajectory with an instrumented manipulandum (MN. The test subjects used the MN with three different levels of stiffness. A transfer function was developed to represent the human application of a precision grip from the data when the test subjects initially displaced the MN so as to learn the position mapping from the MN onto the display. Another transfer function was formed from the data of the remainder of the experiments, after significant displacement of the MN occurred. Both of these transfer functions accurately modelled the system dynamics for a portion of the experiments, but neither was accurate for the duration of the experiments because the human grip dynamics changed while learning the position mapping. Thus, an adaptive system model was developed to describe the learning process of the human test subjects as they displaced the MN in order to gain knowledge of the position mapping. The adaptive system model was subsequently validated following comparison with the human test subject data. An examination of the average absolute error between the position predicted by the adaptive model and the actual experimental data yielded an overall average error of 0.34mm for all three levels of stiffness.

  9. 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...

  10. 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.

  11. Issues in human/computer control of dexterous remote hands

    Science.gov (United States)

    Salisbury, K.

    1987-01-01

    Much research on dexterous robot hands has been aimed at the design and control problems associated with their autonomous operation, while relatively little research has addressed the problem of direct human control. It is likely that these two modes can be combined in a complementary manner yielding more capability than either alone could provide. While many of the issues in mixed computer/human control of dexterous hands parallel those found in supervisory control of traditional remote manipulators, the unique geometry and capabilities of dexterous hands pose many new problems. Among these are the control of redundant degrees of freedom, grasp stabilization and specification of non-anthropomorphic behavior. An overview is given of progress made at the MIT AI Laboratory in control of the Salisbury 3 finger hand, including experiments in grasp planning and manipulation via controlled slip. It is also suggested how we might introduce human control into the process at a variety of functional levels.

  12. Comparison of human and humanoid robot control of upright stance.

    Science.gov (United States)

    Peterka, Robert J

    2009-01-01

    There is considerable recent interest in developing humanoid robots. An important substrate for many motor actions in both humans and biped robots is the ability to maintain a statically or dynamically stable posture. Given the success of the human design, one would expect there are lessons to be learned in formulating a postural control mechanism for robots. In this study we limit ourselves to considering the problem of maintaining upright stance. Human stance control is compared to a suggested method for robot stance control called zero moment point (ZMP) compensation. Results from experimental and modeling studies suggest there are two important subsystems that account for the low- and mid-frequency (DC to approximately 1Hz) dynamic characteristics of human stance control. These subsystems are (1) a "sensory integration" mechanism whereby orientation information from multiple sensory systems encoding body kinematics (i.e. position, velocity) is flexibly combined to provide an overall estimate of body orientation while allowing adjustments (sensory re-weighting) that compensate for changing environmental conditions and (2) an "effort control" mechanism that uses kinetic-related (i.e., force-related) sensory information to reduce the mean deviation of body orientation from upright. Functionally, ZMP compensation is directly analogous to how humans appear to use kinetic feedback to modify the main sensory integration feedback loop controlling body orientation. However, a flexible sensory integration mechanism is missing from robot control leaving the robot vulnerable to instability in conditions where humans are able to maintain stance. We suggest the addition of a simple form of sensory integration to improve robot stance control. We also investigate how the biological constraint of feedback time delay influences the human stance control design. The human system may serve as a guide for improved robot control, but should not be directly copied because the

  13. Kisspeptin and the hypothalamic control of reproduction: lessons from the human.

    Science.gov (United States)

    George, Jyothis T; Seminara, Stephanie B

    2012-11-01

    The hypothalamic hormone GnRH is a central driver of pituitary gonadotropin secretion, controlling pulsatile gonadotropin secretion, modulating gonadal steroid feedback, and bringing about full fertility in the adult. Thus, understanding GnRH neuronal regulation is essential to understanding the neurohumoral control of human reproduction. Genetic tools were used in patients with GnRH deficiency (i.e. idiopathic hypogonadotropic hypogonadism), a clinical syndrome that results from the failure of a normal pattern of pulsatile GnRH, to discover upstream modulators of GnRH secretion (1). In 2003, homozygosity mapping of two consanguineous pedigrees led to the identification of loss of function mutations in KISS1R (a G protein coupled receptor) by two groups (2, 3). In parallel, the Kiss1r(-/-) mouse was shown to be a phenocopy of the human GnRH-deficient state, demonstrating that the function of KISS1R/Kiss1r is conserved across mammalian species (4). Just before these human genetic discoveries, the ligand for kisspeptin-1 receptor [KISS1R; also known as G protein coupled receptor 54 (GPR54)], was discovered to be kisspeptin. Soon thereafter a large array of experimental studies began assembling genetic, expression, physiologic, transgenic, knockdown, and electrophysiological data to characterize the physiology of kisspeptin and its seminal role in modulating GnRH release.

  14. Brief Talk on Technique Progress of Slow-controlled-release Fertilizer in China Based on Corporate Patent Application%从企业专利申请浅谈我国缓/控释肥料的技术发展

    Institute of Scientific and Technical Information of China (English)

    余爱丽

    2011-01-01

    From the definition,classification of slow/controlled-release fertilizer,based on situation of the patent application by corporations,the technique progress of slow-controlled-release fertilizer are introduced,furthermore,from the angle of corporate patent applications,the development trend of slow controlled release fertilizer at present are analysised briefly.%从缓/控释肥料的定义、分类,根据缓/控释肥料在我国的企业专利申请状况,简单地介绍了我国缓/控释肥料的技术发展;另外从企业专利申请的角度,对目前我国缓/控释肥料的发展趋势进行了简要的分析。

  15. 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.

  16. Human response to an individually controlled microenvironment

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Knudsen, G.L.

    2007-01-01

    The response of 48 subjects to an individually controlled microenvironment was studied at room air temperatures of 20 degrees C, 22 degrees C, and 26 degrees C An individually controlled system (ICS) comprising personalized ventilation, an under-desk air terminal device supplying cool air, a chair...... who are comfortable with their microenvironment....

  17. 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.

  18. The effect of dressing controlled release fertilizer on sugarcane yield and benefit in difference growth period%不同生育期追施控释肥料对甘蔗产量及效益的影响

    Institute of Scientific and Technical Information of China (English)

    周柳强; 黄金生; 黄美福; 谢如林; 谭宏伟

    2012-01-01

    Based on the contrast of the sugarcane conventional fertilization (base fertilizer, tillering fertilizer, elongation fertilizer) period, reducing fertilization times of 1-2, the equal fertilization amount, the test results of the two different location show: in tillering to elongation period dressing one-time controlled release fertilizer can keep a certain amount of productive tiller, which is also beneficial to elongation and improving diameter, high sugarcane yield, low labor cost, and worthy to be applied and popularized.%以甘蔗常规施肥(基肥、分蘖肥、伸长肥)为对照,减少1-2次施肥次数,施肥总量不变,两个不同地点的试验结果表明,在分蘖至伸长期间追施一次控释肥料,既可保持一定量的有效茎数,又对甘蔗茎的伸长、增粗有利,并可获得较好的产量,人工费用低,值得推广应用。

  19. Cryopreservation and autotransplantation of human ovarian tissue prior to cytotoxic therapy--a technique in its infancy but already successful in fertility preservation

    DEFF Research Database (Denmark)

    von Wolff, Michael; Donnez, Jacques; Hovatta, Outi

    2009-01-01

    available for fertility preservation in these patients. A new promising method is cryopreservation and transplantation of ovarian cortex. Ovarian tissue can be extracted by laparoscopy without any significant delay of gonadotoxic therapy. The tissue can be cryopreserved by specialised centres...... pregnancies. It emphasises that fertility preservation by the cryopreservation of ovarian tissue is a new but already a successful clinical option, which can be considered for selected cancer patients.......Increasing survival rates in young cancer patients, new reproductive techniques and the growing interest in quality of life after gonadotoxic cancer therapies have placed fertility preservation as an important issue to oncologists, fertility specialists and patients. Several techniques are now...

  20. How chaosity and randomness control human health

    Science.gov (United States)

    Yulmetyev, Renat M.; Yulmetyeva, Dinara; Gafarov, Fail M.

    2005-08-01

    We discuss the fundamental role that chaosity and randomness play in the determination of quality and efficiency of medical treatment. The statistical parameter of non-Markovity from non-equilibrium statistical physics of condensed matters is offered as a quantitative information measure of chaosity and randomness. The role of chaosity and randomness is determined by the phenomenological property, which includes quantitative informational measures of chaosity and randomness and pathology (disease) in a covariant form. Manifestations of the statistical informational behavior of chaosity and randomness are examined while analyzing the chaotic dynamics of RR intervals from human ECG's, the electric signals of a human muscle's tremor of legs in a normal state and at Parkinson disease, the electric potentials of the human brain core from EEG's during epileptic seizure and a human hand finger tremor in Parkinson's disease. The existence of the above stated informational measure allows to introduce the quantitative factor of the quality of treatment. The above-stated examples confirm the existence of new phenomenological property, which is important not only for the decision of medical problems, but also for the analysis of the wide range of problems of physics of complex systems of life and lifeless nature.

  1. Alternative Control Technologies: Human Factors Issues

    Science.gov (United States)

    1998-10-01

    vertical vibration to the 29,4, 1980, pp 462-466. head and shoulders of seated men", Royal Aircraft Lee, J. M.; Chartier , V. L.; Hartmann, D. P.; Lee, G...Suarez, P. F., Rogers , S., K., Ruck, D. W., for Effective Human-Computer Interaction", 2nd edition, Arndt, C., and Kabrisky, M., "A facial feature

  2. Design and experiment of automatic mixing apparatus for liquid fertilizer based on fuzzy control%基于模糊控制的肥液自动混合装置设计与试验

    Institute of Scientific and Technical Information of China (English)

    李加念; 洪添胜; 冯瑞珏; 倪慧娜

    2013-01-01

      为提高混肥精度,该文在基于脉宽调制的文丘里变量施肥装置的基础上,对其结构进行了改进,并利用电导电极设计了一个电导率测量仪用以实时反馈肥液浓度,使之构成一个闭环控制的自动混肥装置。该装置采用粗细2级调节的控制策略,首先根据检测的入口水压调用对应的函数关系,自动调节电磁阀 PWM(pulse width modulation)控制的占空比进行混肥;然后以电导率测量仪实时反馈混肥浓度,并采用模糊控制算法进一步细调PWM的占空比,使混肥浓度尽量逼近目标浓度。试验结果表明,电导率测量仪的有效测量范围为0~12.64 mS/cm,它所测量的电导率与肥液浓度呈显著的线性关系,其决定系数 R2为0.997。对混肥装置进行了实测验证,结果表明混肥时的最大浓度误差为0.04%,控制装置达到稳态的响应时间为7.8~10.4 s,能满足实际应用的要求。%Fertigation is an irrigation technology of integration of water and fertilizer, and has been widely used in micro-irrigation systems, because of uniform fertilization, high utilization of water and fertilizer, and effectively reducing the pollution of soil and environment. The venturi fertilizer injector has become one of the main means and important equipment to achieve fertigation due to its simple structure, economy, and practicability, but the liquid fertilizer concentration could not be easily adjusted automatically. In order to realize variable rate fertilization with a venturi fertilizer injector, a variable fertilizer apparatus based on PWM (pulse width modulation) technology has been developed, but the apparatus belongs to open-loop control from the perspective of automatic control, and its accuracy and stability is difficult to guarantee. Therefore, a closed-loop control automatic fertilizer-mixing device was developed to improve the liquid fertilizer concentration mixing accuracy and

  3. Fertilization potential and qualitative characteristics of human spermatozoa after short-term cryostorage at 5 degrees C in two different TEST-yolk buffer preparations.

    Science.gov (United States)

    Zavos, P M; Correa, J R; Foster, C L; Massey, J B; Zarmakoupis-Zavos, P N

    1998-02-01

    preparations and further prepared via filtration, was assessed by the sperm penetration assay (SPA) using zona-free hamster oocytes. The average penetration rate (PR) and penetration index (PI) were significantly better for the NT-TYB than for the T-TYB. The PR was 54% vs. 25%, and the PI 0.78 and 0.27 for spermatozoa incubated in the NT-TYB vs. T-TYB. The range of penetration was also much lower for the T-TYB (6 to 100%) preparation when compared to the NT-TYB (22 to 100%). The highest penetrator showed 100% for both preparations. However, the lowest penetrator showed 6% for the T-TYB and 22% for the NT-TYB. The data obtained in this study suggest that both TYB preparations can be employed in short-term cryostorage (5 degrees C) of human spermatozoa and can adequately maintain the qualitative characteristics of those spermatozoa. The data also showed that the NT-TYB preparation yielded sperm samples of higher fertilization potential, thus possibly establishing the superior usefulness of the NT-TYB in an ART program.

  4. Human response to an individually controlled microenvironment

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Knudsen, G.L.

    2007-01-01

    The response of 48 subjects to an individually controlled microenvironment was studied at room air temperatures of 20 degrees C, 22 degrees C, and 26 degrees C An individually controlled system (ICS) comprising personalized ventilation, an under-desk air terminal device supplying cool air, a chair...... with convectively heated backrest, an under-desk radiant heating panel, and a floor-heating panel were used. The temperature of the air supplied from the personalized ventilation and the under-desk device was 20 degrees C The subjects were provided with control of the flow rate and direction of the personalized air...... at a room temperature of 22 degrees C without ICS. Thus, ICS will increase the number of satisfied occupants when applied in practice. The design and control of the ICS, as well as the background air distribution in a room, should be carefully considered in order to obtain the maximum number of occupants...

  5. Plant Modeling for Human Supervisory Control

    DEFF Research Database (Denmark)

    Lind, Morten

    1999-01-01

    This paper provides an overview of multilevel flow modelling (MFM) and its application for design of displays for the supervisory control of industrial plant. The problem of designing the inforrrzatian content of sacpervisory displays is discussed and plant representations like MFM using levels...... is also provided by an analysis of the relations between levels of abstraction. It is also described how MFM supparts reazsonin about control actions by defining levels of intervention and by modal distinctions between function enablement and initiation....

  6. Bioremediation of residual fertilizer nitrate: I. Laboratory demonstration of an on-farm in situ pollution control system.

    Science.gov (United States)

    Ugwuegbu, B U; Prasher, S O; Ahmad, D

    2001-01-01

    This exploratory laboratory study was undertaken to develop and test an in situ bioremediation system intended to point the way toward a possible field application. The proposed method uses a water table management (WTM) system to deliver nutrients or other amendments to subsoil microorganisms for biostimulation and subsequent biodegradation of pollutants in the saturated and unsaturated zones of the soil. The study was carried out on packed soil columns and bioremediation of residual fertilizer nitrate was attempted. Different levels of organic carbon supplement (glucose C) were introduced into these columns via subirrigation in order to supplement the readily available organic carbon levels in the soil. The study was carried out in two experimental setups. The first setup investigated (i) the effect of addition of a high (970 mg L(-1)) and a low (120 mg L(-1)) glucose C level and (ii) the efficacy of using the subirrigation system as a method for nutrient delivery in bioremediation of leached nitrate. This setup was monitored with time, depth, and with reference to the nitrate residue in the soil solution. Leached nitrate was denitrified to less than 10 mg L(-1) nitrate N at both glucose levels. The second setup investigated the effect of a range of low levels of glucose C on nitrate decontamination, soil pH, and total microbial count in order to find out an optimal glucose C level that reduced the most nitrate and maintained the pH homeostasis of soil.

  7. Effects of bag-controlled fertilization on contents of soil nutrients and soil enzymes activities of sugarcane land%袋控施肥对甘蔗地土壤养分含量和酶活性的影响

    Institute of Scientific and Technical Information of China (English)

    汪帆; 林德喜; 袁照年; 张华

    2016-01-01

    为了提高肥料利用率和节约劳动力,通过2年田间试验探讨了袋控施肥对甘蔗产量、蔗地土壤养分含量和土壤酶活性的影响。结果表明:在总养分一致、两季甘蔗只施1次肥料条件下,3种复混肥(复混肥A、B分别为60%包膜、30%包膜缓释肥与尿素和氯化钾的混合肥,复混肥F为常规复合肥)均为袋控施用处理蔗茎产量高于常规施用处理,其中以 CB2处理(2孔复混肥B袋控处理)蔗茎平均产量最高(114�44 t/hm2)。蔗茎产量和土壤有效磷、速效钾含量,以及脲酶、蔗糖酶活性在宿根年均表现为复混肥A、B处理高于复混肥F处理,且在相同的施肥量下以2孔袋控施肥最佳。复混肥B处理宿根年土壤碱解氮含量最少,均低于70 mg/kg。3种复混肥处理磷酸酶活性均表现为常规施肥处理高于袋控施肥处理。可见,袋控施肥的蔗茎产量高于常规施肥,复混肥A、B的袋控施肥处理能保证养分稳定释放,并在一定程度上提高甘蔗产量、土壤养分含量和酶活性,其中以复混肥B的2孔袋控施肥处理效果最好。%Field experiments were carried out for two years to investigate the effects of bag controlled fertilization on sugarcane yield, soil nutrient content and soil enzymes activities for improving fertilizer use efficiency and saving labor. Three kinds of compound fertilizers were tested. Compound fertilizer A and B were 60% and 30% of coated fertilizer mixed with urea and potassium chloride respectively, and fertilizer F was the conventional compound fertilizer. Fertilizers A, B and F were packed in bags with 2 holes or 4 holes. Treatments with bag controlled fertilizers A, B and F had higher sugar⁃cane yield than the treatments with conventional fertilization ( no bag). The treatment CB2 (fertilizer B packed in a 2⁃hole bag) showed the highest yield of 114�44 t/hm2 . Cane yield, soil a⁃vailable phosphorus

  8. A matched case-control study comparing udder health, production and fertility parameters in dairy farms before and after the eradication of Bovine Virus Diarrhoea in Switzerland.

    Science.gov (United States)

    Tschopp, A; Deiss, R; Rotzer, M; Wanda, S; Thomann, B; Schüpbach-Regula, G; Meylan, M

    2017-09-01

    An obligatory eradication programme for Bovine Virus Diarrhoea (BVD) was implemented in Switzerland in 2008. Between 2008 and 2012, all bovines were tested for antigen or antibodies against BVDV. By the year 2012, eradication was completed in the majority of farms. A decrease of the prevalence of persistently infected (PI) newborn calves was observed from 1.4% in 2008 to animal health, production and fertility in Swiss dairy herds which had completed the eradication programme. A matched case-control study was carried out using data from two periods, before (Period 1) and after (Period 2) the active phase of eradication. Case farms had at least two PI animals detected before or during the eradication; controls were BVD-free and matched for region, herd size and use of alpine pasture. A total of 110 farmers (55 pairs) were recruited. During a phone interview, a questionnaire about farm characteristics, animal health and appreciation of the BVD eradication programme was filled in. Breeding data and milk test day records were also analyzed. Parameters were first compared between (i) case and control herds before eradication, and (ii) Period 1 and Period 2 for case herds only. Milk yield (MY), bulk milk somatic cell count (BMSCC), prevalence of subclinical mastitis (SCM), and non-return rate (NRR) showed a p-value<0.25 in at least one of the univariable comparisons and were thus further analyzed with a multilevel mixed-effects model to account for repeated measures over time. In order to assess whether changes in health status over time were due to BVD eradication, an interaction variable between period and group (case-control) was created (IA). Except for MY, the IA was significant for all parameters modelled. Despite an overall p-value of 0.27, case herds tended to have a higher MY after eradication (β=0.53, p=0.050). For BMSCC and SCM, case herds had higher values than controls in both periods; udder health was significantly improved in control herds and it remained

  9. 掺混型缓/控释肥对杂交晚稻产量的影响%Effect of slow/controlled-release fertilizer on yield of late hybrid rice

    Institute of Scientific and Technical Information of China (English)

    王玉军; 邹应斌; 张夫道

    2009-01-01

    Field experiment was trialed to study effect of slow/controlled-release fertilizer on yield of late hybrid rice and CK1 was no fertilizer and CK2 was same amount of NPK. The results showed that yields of slow/controlled-release fertilizer treatments were higher than NPK treatment Compared to NPK treatment, in Changsha normal fertility paddy soil, the effect was best for 35%polyethylene alcohol mixing for adhesive (CF2) felted fertilizer+65% wasted foam (PS) mixed and coated fertilizer (for short CF2 + PS) that increased yield by 27. 68% , and the second was 35% kaolin-polyesterfelted fertilizer + 65% PS coated fertilizer and yield increased by 24. 70%. In Ningxiang low fertility paddy soil, the effect was best for 35% kaolin-polyesterfelted fertilizer +65% PS coated fertilizer and yield increased by 37. 25% , effect of increasing yield for treatments in Ningxiang were better than that of treatments in Changsha. The lower fertility of soil and the higher of increasing rate of fertilizer. Compared to NPK treatment, yield was higher when amount of blend slow release fertilizer decreased by 20%. According to crop grow period, the effects of blending slow release fertilizer with different nutrient release period in some percentage were better.%采用田间小区试验,以不施肥(CK1)和施用等量NPK化肥(CK2)为对照,研究掺混型缓/控释肥对水稻产量的影响.结果表明,各缓释肥处理的产量均高于等量NPK处理.其中,在长沙点中肥力水稻土上,35%聚乙烯醇混聚物(CF2)胶结复混肥+65%废弃泡沫塑料(PS)混聚物包膜复混肥(简称CF2+PS)效果最好,比等量NPK处理增产27.68%,其次是35%高岭土-聚酯胶结肥+65%PS包膜肥,比等量NPK处理增产24.70%;在宁乡点低肥力水稻土上,35%高岭土-聚酯胶结肥+65%PS包膜肥处理效果最好,比等量NPK处理增产37.25%;宁乡试验点各施肥处理的增产效果均高于长沙点,说明土壤肥力越低,肥料的增产率越高;减少20%掺

  10. Effects of Controlled-release N Fertilizers on Maize and Cabbage Growth%控释氮肥对玉米和大白菜生长发育的影响

    Institute of Scientific and Technical Information of China (English)

    刘安勋; 廖宗文

    2011-01-01

    [Objective] The research aimed to study the controlled-release character of controlled-release N fertilizer. [ Method] Effects of con-trolled-release N fertilizers on the growth of maize and Chinese' cabbage and soil N content were studied through a field experiment. [Result] All controlled-release N fertilizers were basal applied,which were better than conventional fertilizer used,and the same as more 10% N used. And corn biological yield were 8.8% and 5.2% higher respectively. Controlled-release effect of PK were better than that of MFSU-Xin. PK and MFSU-Xin could significantly increase relative fertilizer efficiency by 89.2% and 53. 2% respectively. [Conclusion] Controlled-release N fertilizer increased soil N and it could provide more N to future crop.%[目的]为了研究控释氮肥的控释性能.[方法]通过田间试验,研究2种控释氮肥在玉米和大白菜上的施用效果和对土壤氮素养分的影响.[结果]控释肥一次施入肥效明显地优于常规施肥,与多追施10%氯效果相近,玉米生物产量分别比常规施氮增加8.8%和5.2%,PK包膜尿素的控释效果比MFSU-Xin包膜尿素好.控释肥可明显提高氮肥的利用率,PK和MFSU-Xin控释肥利用率分别比常施肥提高89.2%和53.2%.[结论]控释肥可以增加土壤后效,为下季作物提供较多氮素.

  11. Effect of Organic and Inorganic Fertilizers on Growth and Yield of Tef ...

    African Journals Online (AJOL)

    toshiba

    over inorganic fertilizers mainly because these materials decompose, and hence release .... Nitrogen and P fertilizers were applied in the form of Urea and DAP .... vermicompost plus 50% N and P fertilizers, where as the control treatment (no.

  12. Comparison of nutrient release characteristics between 2 kinds of controlled-release BB fertilizer%2种控释BB肥养分控释性能的比较

    Institute of Scientific and Technical Information of China (English)

    张秀玮; 王全辉; 董元杰; 刘春生

    2012-01-01

    The nutrient release characteristics of two different controlled-release BB fertilizers in the 25 water are studied. The results show that 2 kinds of controlled-release BB fertilizers have the effect of nutrient controlled release, which is better in nitrogen, and is poor in phosphorus and potassium. Nitrogen controlled release effect of controlled-release BB fertilizer 1 is better than that of controlled-release BB fertilizer 2, which is opposite to phosphorus and potassium.%在25℃静水释放试验条件下,对2种控释BB肥的控释性能进行了研究。结果表明:2种控释BB肥对养分均有一定的控释性能,对氮素的控释效果最好,磷、钾控释效果较差。两种控释BB肥相比,控释BB肥1对氮的控释效果优于控释BB肥2,而控释BB肥2对磷、钾的控释效果优于控释BB肥1。

  13. Effects of Controlled-release Fertilizer on Potato Growth and Soil Enzyme Activities%控释肥对马铃薯生长及土壤酶活性的影响

    Institute of Scientific and Technical Information of China (English)

    刘飞; 诸葛玉平; 王会; 朱利

    2011-01-01

    Field experiment was conducted to study the effects of controlled-release fertilizer on potato growth and soil enzyme activities. The results indicated that:Compared with ordinary fertilizer, the plant height, stem diameter and chlorophyll were significantly increased by the application of controlled-release fertilizer, which respectively increased by 5.94%, 9.04% and 5. 55%. Furthermore, when the amount of controlled-release fertilizer was reduced by 20%, there was no significant change on the promotion effect. Both of the two fertilizers could improve the activities of phosphatase and sucrase, but the promotion effect of controlled-release fertilizer was significantly better than ordinary fertilizer, respectively increased by 10.2% and 14.62%. The controlled-release fertilizer increased the activity of urease by an average of 15.7%,while the ordinary fertilizer inhibited it. The controlled-release fertilizer could also cause some degree of inhibition on catalase activity which was decreased by an average of 11.13%. Compared with other controlled-release fertilization processing, a reduction to the controlled-release fertilization by 20% could decrease the promotion of the urease activity by 9.41 % ,and the promotion of the phosphatase activity by 9.02% ,increase the promotion of sucrase activity by 5. 56 %, and decrease the inhibition of catalase activity by 5.2%.%通过马铃薯田间试验,研究了控释肥对马铃著生长和土壤酶活性的影响.结果表明,与普通肥料相比,控释肥有利于提高马铃薯的株高、茎粗和叶绿索含量,分别提高5.94%,9.04%,5.55%,且控释肥减量20%仍不影响其促进作用.施用控释肥和普通化肥都可以促进土壤酸性磷酸酶和蔗糖酶活性,但控释肥平均比普通肥料的促进作用分别提高10.2%和14.62%,控释肥显著优于普通肥料;控释肥可促进脲酶活性,平均提高15.7%,而普通肥料会对其产生抑制;控释肥处理会对土壤

  14. The Effect of a Two-Hour, Room Temperature Incubation of Human Spermatozoa in TEST-Yolk Buffer on the Rate of Fertilization in Vitro

    OpenAIRE

    Jensen, Julie R.; Walker, John H.; Milki, Amin A.; Westphal, Lynn; Behr, Barry

    2004-01-01

    Patients: To reassess the use of TEST-yolk buffer (TYB) in an in vitro fertilization (IVF) program by comparing fertilization rates achieved in a glucose-free cleavage medium by the standard IVF preparation of sperm versus a 2-h, room temperature incubation of sperm in TYB.

  15. Not All Sperm Are Equal: Functional Mitochondria Characterize a Subpopulation of Human Sperm with Better Fertilization Potential

    OpenAIRE

    Ana Paula Sousa; Alexandra Amaral; Marta Baptista; Renata Tavares; Pedro Caballero Campo; Pedro Caballero Peregrín; Albertina Freitas; Artur Paiva; Teresa Almeida-Santos; João Ramalho-Santos

    2011-01-01

    Human sperm samples are very heterogeneous and include a low amount of truly functional gametes. Distinct strategies have been developed to characterize and isolate this specific subpopulation. In this study we have used fluorescence microscopy and fluorescence-activated cell sorting to determine if mitochondrial function, as assessed using mitochondrialsensitive probes, could be employed as a criterion to obtain more functional sperm from a given ejaculate. We first determined th...

  16. Adubo de liberação lenta na produção de mudas de mamoeiro Controlled-release fertilizer in papaya seedlings production

    Directory of Open Access Journals (Sweden)

    Luiz Augusto Lopes Serrano

    2010-09-01

    Full Text Available O objetivo deste trabalho foi definir as doses adequadas de um adubo de liberação lenta para a produção de mudas dos principais genótipos de mamoeiro cultivados no Estado do Espírito Santo. O experimento foi realizado em estufa agrícola, na Empresa Caliman Agrícola S.A., em Linhares-ES, sob delineamento de blocos casualizados, em esquema fatorial 5x6. Foram avaliados cinco genótipos de mamoeiro 'Golden', 'Calimosa', 'Tainung 01', 'INCAPER 09' e 'INCAPER 39', cultivados em substrato comercial fertilizado com seis doses de um adubo de liberação lenta, fórmula NPK + (Mg 13-06-16 + (1,4: 0,0; 2,5; 5,0; 7,5; 10,0 e 12,5 kg m-3. Houve diferenças no crescimento e no estado nutricional das mudas de mamoeiro em relação ao genótipo e às doses do adubo de liberação lenta utilizados. As doses do adubo que proporcionaram os maiores valores para altura e massa seca total das mudas de mamoeiro foram: 11,2 e 11,3 kg m-3 para o 'Golden'; 7,7 e 7,9 kg m-3 para o 'Calimosa'; 11,6 e 10,9 kg m-3 para o 'Tainung 01'; 10,5 e 10,6 kg m-3 para o 'INCAPER 09', e 11,0 e 9,6 kg m-3 para o 'INCAPER 39', respectivamente. Nessas mesmas doses do adubo, as mudas apresentaram adequado nível nutricional.The objective of this work was to define the appropriate doses of a controlled-release fertilizer to production of papaya seedlings, in Espirito Santo State, Brazil. The research was realized in greenhouse in Caliman Agricola Company, Linhares- ES, Brazil. The experimental design was a randomized complete block in a factorial scheme 5x6. It was evaluated five papaya genotypes 'Golden', 'Calimosa', 'Tainung 01', 'INCAPER 09' and 'INCAPER 39', cultivated in commercial substrate (constituted of pinus bark and vermiculite fertilized with six doses of controlled-release fertilizer formula NPK + (Mg 13-06-16 + (1.4: 0.0; 2.5; 5.0; 7.5; 10.0 and 12.5 kg m-3. Differences in growth and nutritional status of papaya seedlings were observed according to the genotype and

  17. Effect of Application of Base Controlled Release Fertilizers and Top Dressing of Various Proportions of Ordinary Urea on Yield of Summer Corn and Utilization Ratio of Nitrogenous Fertilizers%控释肥料基施及普通尿素不同基追比对夏玉米产量及氮肥利用率的影响

    Institute of Scientific and Technical Information of China (English)

    孙克刚; 张欣; 李丙奇; 刘京宝; 和爱玲

    2011-01-01

    研究了控释尿素和控释BB肥一次性基施后的肥料效果,以及普通尿素不同基追比对玉米产量和氮肥利用率的影响.研究结果表明:以33.3%普通尿素基施+33.3%大喇叭口期追施+33.3%抽雄期追施的处理最佳,产量最高达8 700 kg/hm2,氮肥利用率为34.3%.控释尿素基施处理和控释BB肥基施处理的氮肥利用率分别为41.7%和44.1%,均高于施用普通尿素的各处理,且控释BB肥基施处理的氮肥利用率高于控释尿素基施处理.%A study is made of the fertilizer effect of base application once of controlled release urea and bulk blending ( BB) fertilizers as well as various proportions of top dressing of ordinary urea on corn yield and utilization ratio of nitrogenous fertilizers. The results show that the best treatment method is the use of base application with 33. 3% ordinary urea plus top dressing with 33. 3% at big trumpet period plus top dressing with 33. 3% in tasseling period, the highest yield is 8 700 kg/hm2, and the utilization ratio of the nitrogenous fertilizers is 34. 3%. When controlled release urea and controlled release BB fertilizers are base applied, the nitrogen fertilizer utilization ratio is 41.7% and 44.1% ,respectively, higher than various treatments with ordinary urea, and the utilization of base applied controlled release BB fertilizers is higher than that of base applied controlled release urea.

  18. Fecundidade e diferenciais intra-urbanos de desenvolvimento humano, São Paulo, Brasil, 1997 Fertility and its intra-urban differentials of human development, Brazil, 1997

    Directory of Open Access Journals (Sweden)

    Cláudia Maria Martins

    2001-10-01

    Full Text Available OBJETIVO: Avaliar possíveis divergências no padrão reprodutivo de mulheres residentes em áreas de diferentes níveis de desenvolvimento humano, pela análise de suas taxas de fecundidade total e taxas específicas de fecundidade por idade. MÉTODOS: Foram estudados os 96 distritos do Município de São Paulo, agrupados em cinco áreas segundo ordem crescente dos valores assumidos pelo Indicador de Desenvolvimento Humano. O estudo compreendeu a população feminina de