WorldWideScience

Sample records for hybrid embryo research

  1. Fearing a non-existing Minotaur? The ethical challenges of research on cytoplasmic hybrid embryos.

    Science.gov (United States)

    Camporesi, S; Boniolo, G

    2008-11-01

    In this paper we address the ethical challenges of research on cytoplasmic hybrid embryos, or "cybrids". The controversial pronouncement of the UK's Human Embryology and Fertilisation Authority of September 2007 on the permissibility of this area of research is the starting point of our discussion, and we argue in its favour. By a rigorous definition of the entities at issue, we show how the terms "chimera" and "hybrid" are improper in the case of cybrids, and how their use can bias the debate creating moral prejudices. After analysing the scientific aspects of cybrids research and sketching out current alternatives, we enter the ethical debate, starting from the premise that research on early human embryos is ethically permissible under some circumstances. We emphasise how research on cybrids has positive consequences in terms of scientific and therapeutic applications, since it allows the derivation of human embryonic stem cells genetically tailored to the somatic cell donor. Such cell lines offer a unique in vitro model both for studies of human pathogenesis and for drug screening and discovery. Research on cybrids also circumvents the problem of the scarcity of human oocytes and their ethically dubious donation. Finally, we object to the most common arguments against cybrids research, that is, moral repugnance, the slippery slope argument, the appeal to "nature", and the unfair distribution of economical resources.

  2. Hybrids of sugar pine by embryo culture

    Science.gov (United States)

    E. C. Stone; J. W. Duffield

    1950-01-01

    A modified embryo culture technique was used to facilitate germination of seed obtained after pollinating sugar pine with pollen from blister rust- resistant Armand and Korean pines. Resulting seedlings appear to be hybrids.

  3. Hybridization between Gossypium herbaceum and Gossypium stochsii through embryo rescue

    Institute of Scientific and Technical Information of China (English)

    GILLMANJEETS; YPSBAJAJ

    1996-01-01

    Nutrient media and culture conditions have been defined for ovules 3 and 5 d after pollination and embryos of Gossypium herbaceum respectively.The technique was then used to produce interspecific hybrids between a cultivated Gossypium herbaceum and a wild species,G.stocksii.The hybrid plants were transferred to field and they exhibited most of the characters of the pollen parent i.e.G.stocksii.

  4. In vitro embryo rescue of interspecific hybrids of oil palm (Elaeis oleifera x Elaeis guineensis)

    OpenAIRE

    Alves, Sergio Augusto Oliveira; de Lemos, Oriel Filgueira; Filho,Benedito Gomes dos Santos; da Silva, André Luís Lopes

    2011-01-01

    The oil palm (Elaeis guineennsis Jacq.) is the plant with major oil yield in tropical areas over the world. Pará state is the major producer of Brazil. However, the production of resistant hybrids (Elaeis oleifera x Elaeis guinennsis) to several diseases is necessary, in spite of less productive, is a viable alternative for areas where occur more aggressive diseases. The aim of this research was to rescue in vitro embryos of four varieties of interspecific hybrids of oil palm (Elaeis oleifera...

  5. Moral qualms, future persons, and embryo research.

    Science.gov (United States)

    Shaw, David Martin

    2008-05-01

    Many people have moral qualms about embryo research, feeling that embryos must deserve some kind of protection, if not so much as is afforded to persons. This paper will show that these qualms serve to camouflage motives that are really prudential, at the cost of also obscuring the real ethical issues at play in the debate concerning embryo research and therapeutic cloning. This in turn leads to fallacious use of the Actions/Omissions Distinction and ultimately neglects the duties that we have towards future persons.

  6. Researchers Create Artificial Mouse 'Embryo'

    Science.gov (United States)

    ... the University of Cambridge explained that in regular reproduction, when a mammal's egg has been fertilized by ... the researchers said, though it's noted research with animal models often fails to produce similar results with ...

  7. Researchers Put Embryo Development 'On Hold' in Mice

    Science.gov (United States)

    ... medlineplus.gov/news/fullstory_162187.html Researchers Put Embryo Development 'On Hold' in Mice Putting stem cells ... were able to halt development of early mouse embryos for up to a month in the lab ...

  8. Potential of human twin embryos generated by embryo splitting in assisted reproduction and research.

    Science.gov (United States)

    Noli, Laila; Ogilvie, Caroline; Khalaf, Yacoub; Ilic, Dusko

    2017-03-01

    Embryo splitting or twinning has been widely used in veterinary medicine over 20 years to generate monozygotic twins with desirable genetic characteristics. The first human embryo splitting, reported in 1993, triggered fierce ethical debate on human embryo cloning. Since Dolly the sheep was born in 1997, the international community has acknowledged the complexity of the moral arguments related to this research and has expressed concerns about the potential for reproductive cloning in humans. A number of countries have formulated bans either through laws, decrees or official statements. However, in general, these laws specifically define cloning as an embryo that is generated via nuclear transfer (NT) and do not mention embryo splitting. Only the UK includes under cloning both embryo splitting and NT in the same legislation. On the contrary, the Ethics Committee of the American Society for Reproductive Medicine does not have a major ethical objection to transferring two or more artificially created embryos with the same genome with the aim of producing a single pregnancy, stating that 'since embryo splitting has the potential to improve the efficacy of IVF treatments for infertility, research to investigate the technique is ethically acceptable'. Embryo splitting has been introduced successfully to the veterinary medicine several decades ago and today is a part of standard practice. We present here an overview of embryo splitting experiments in humans and non-human primates and discuss the potential of this technology in assisted reproduction and research. A comprehensive literature search was carried out using PUBMED and Google Scholar databases to identify studies on embryo splitting in humans and non-human primates. 'Embryo splitting' and 'embryo twinning' were used as the keywords, alone or in combination with other search phrases relevant to the topics of biology of preimplantation embryos. A very limited number of studies have been conducted in humans and non

  9. Research Progress on Technique of Frozen Embryo Transfer in Sheep

    Institute of Scientific and Technical Information of China (English)

    SHE Qiu-sheng; HU Jian-ye; LOU Peng-yan; TAO Jing; XIE Zhao-hui

    2011-01-01

    The paper introduced the research progress on the technique of frozen embryo transfer in sheep, illustrated selection of donors and receptors, superovulation, synchronization of estrus, embryo cryopreservation and embryo transplantation. Frozen embryo transfer in sheep is another breakthrough in the high-quality sheep raising, and this technique in China is in its infancy recommendation stage, but it will be comprehensively popularized in the future.

  10. Identification of the Sex of Earlier Embryos from Generic Hybrids of Chicken-Quail by Wpkci

    Institute of Scientific and Technical Information of China (English)

    QIAO Ai-jun; MA Wen-xia; LI Da-quan; MENG Qing-mei

    2008-01-01

    In this study,a protocol was deveolped the sex of earlier embryos of chicken(♂)-quail(♀)hybrids and successfully tested the sex proportion of each period (66-120 h). We acquired cross bred eggs by artificial insemination, hatched them in the same batch according to the standard hatching condition of chicken, and collected earlier living embryos at 66,72,78, 84,90,96,102,108,114, and 120 h randomly. We adopted RT-PCR protocol and multiple PCR, made the known sex quail as the external control, employed β-actin as the internal control, and used primers that were designed according to conservative area of gene Wpkci of quail to identify the sex of earlier hybrid embryos. The results indicated that the primer of Wpkci can be used to identify the sex of hybrid embryos accurately; there were more male than female in earlier embryos, the sex proportion of earlier embryos compared with academic numerical value was significantly different (P0.05). In the present study, we concluded that a simple, fast, credible and stable protocol to identify the sex of earlier hybrids embryos had been established by using primer of Wpkci; in earlier embryos, the death rate of female was higher than that of male and there was no fluctuant peak.

  11. Plant Regeneration and Somatic Embryogenesis from Immature Embryos Derived through Interspecific Hybridization among Different Carica Species

    Directory of Open Access Journals (Sweden)

    Latifah Amin

    2012-12-01

    Full Text Available Plant regeneration and somatic embryogenesis through interspecific hybridization among different Carica species were studied for the development of a papaya ringspot virus-resistant variety. The maximum fruit sets were recorded from the cross of the native variety C. papaya cv. Shahi with the wild species C. cauliflora. The highest hybrid embryos were recorded at 90 days after pollination and the embryos were aborted at 150 days after pollination. The immature hybrid embryos were used for plant regeneration and somatic embryogenesis. The 90-day-old hybrid embryos from the cross of C. papaya cv. Shahi × C. cauliflora showed the highest percentage of germination, as well as plant regeneration on growth regulators free culture medium after 7 days pre-incubation on half-strength MS medium supplemented with 0.2 mg/L BAP, 0.5 mg/L NAA and 60 g/L sucrose. The 90-day-old hybrid embryos from the cross of C. papaya cv. Shahi × C. cauliflora produced maximum callus, as well as somatic embryos when cultured on half-strength MS medium containing 5 mg/L 2,4-D, 100 mg/L glutamine, 100 mg/L casein hydrolysate and 60 g/L sucrose. The somatic embryos were transferred into half-strength MS medium containing 0.5 mg/L BAP and 0.2 mg/L NAA and 60 g/L sucrose for maturation. The highest number of regenerated plants per hybrid embryo (10.33 was recorded from the cross of C. papaya cv. Shahi × C. cauliflora. Isoenzyme and dendrogram cluster analysis using UPGMA of the regenerated F1 plantlets confirmed the presence of the hybrid plantlets.

  12. Interspecific hybridization of Trifolium alexandrinum with T. constantinopolitanum using embryo rescue.

    Science.gov (United States)

    Roy, A K; Malaviya, D R; Kaushal, P; Kumar, B; Tiwari, A

    2004-04-01

    The embryo rescue technique was successfully used to raise hybrids between Trifolium alexandrinum and T. constantinopolitanum. As a result of its narrow genetic base, genetic improvement in Egyptian clover (syn. Berseem; T. alexandrinum), an important fodder crop in tropical and subtropical countries, is hampered, thereby making it imperative to introduce alien genes from related species. In a conventional interspecific hybridization program, hybrids could not be raised due to post-fertilization barriers. Of the several combinations tried, pollination 2 days after emasculation was found to be the best. Globular embryos were observed 5-7 days after pollination (DAP), followed by heart-shaped embryos 10-12 DAP. Embryos excised at the heart-shaped stage responded well to EC3 culture medium. Of 612 crosses, 33 healthy embryos could be excised and cultured on EC3 medium. The plumule emerged 8-12 days following inoculation. The embryo-rescued plants were hardened, inoculated with Rhizobium and transferred to the field. The hybrids showed intermediate morphological features with reduced pollen fertility (55-65%) and a chromosomal complement of 2n = 16. Biochemical characterization using isozymes confirmed hybridity.

  13. Embryogenic calli induced in interspecific (Elaeis guineensis x E. oleifera hybrid zygotic embryos

    Directory of Open Access Journals (Sweden)

    Paula Cristina da Silva Angelo

    2009-01-01

    Full Text Available The hybridization between oil palm (Elaeis guineensis and caiaué (E. oleifera plants is directed to obtainprogenies presenting high yields like oil palm but with reduced shoot height and resistance to lethal yellowing like caiaué.Cloning F1, BC1 and BC2 progenies can make the replication of selection trials easier. The objective of this work was to inducesomatic embryogenesis in interspecific zygotic embryos collected 100 days after pollination. Three progenies were cultivatedin an induction medium developed for Tenera (E. guineensis tp. dura x pisifera embryos. The number of embryos bearing calliand germinating was recorded and submitted to the Z test. Calli were weighted and submitted to histological analysis.Progenies differed in the number of embryos presenting plumules and calli simultaneously. By the ninth month, the apices ofincompletely developed somatic embryos were observed protruding from the surfaces of nodular calli. Highly embryogenicand friable secondary calli producing globular somatic embryos were not observed.

  14. Genetic modification of preimplantation embryos: toward adequate human research policies.

    Science.gov (United States)

    Dresser, Rebecca

    2004-01-01

    Citing advances in transgenic animal research and setbacks in human trials of somatic cell genetic interventions, some scientists and others want to begin planning for research involving the genetic modification of human embryos. Because this form of genetic modification could affect later-born children and their offspring, the protection of human subjects should be a priority in decisions about whether to proceed with such research. Yet because of gaps in existing federal policies, embryo modification proposals might not receive adequate scientific and ethical scrutiny. This article describes current policy shortcomings and recommends policy actions designed to ensure that the investigational genetic modification of embryos meets accepted standards for research on human subjects.

  15. Creating New Germplasm by Distant Hybridization in Stone Fruits:Ⅱ-Embryo Rescue and Hybrid Identification Between Plum and Apricot

    Institute of Scientific and Technical Information of China (English)

    YANG Hong-hua; CHEN Xue-sen; FENG Bao-chun; LIU Huan-fang; ZHENG Zhou

    2004-01-01

    Embryo abortion stage and rescue system of hybrids were studied in the distant hybridization between plum and apricot. Identification of the hybrids was also made. The results showed:(1)Embryo abortion started from three weeks after pollination.(2)The germination and growth of embryos were different at different growth stages,which could germinate and grow with PF value> 0.5,but failed with PF value< 0.5. In embryo rescue system of hybrids,the best germination and differentiation medium was MS + 6-BA 2 mg L-1+ IAA 0.3 mg L-1,the rate of germination and differentiation reached up to 80%,bud induction and multiplication medium was MS + 6-BA 1.5 mg L-1+ IAA 0.3 mg L-1,rooting medium was 1/2 MS + IAA0.8mgL-1. Some hybrids were transplanted into the field successfully.(3)Leaf shape investigation and identification by S allele-specific PCR and RAPDs showed that the hybrids were true ones.

  16. Genetic Modification of Preimplantation Embryos: Toward Adequate Human Research Policies

    OpenAIRE

    Dresser, Rebecca

    2004-01-01

    Citing advances in transgenic animal research and setbacks in human trials of somatic cell genetic interventions, some scientists and others want to begin planning for research involving the genetic modification of human embryos. Because this form of genetic modification could affect later-born children and their offspring, the protection of human subjects should be a priority in decisions about whether to proceed with such research. Yet because of gaps in existing federal policies, embryo mo...

  17. New Tools for Embryo Selection: Comprehensive Chromosome Screening by Array Comparative Genomic Hybridization

    Directory of Open Access Journals (Sweden)

    Lorena Rodrigo

    2014-01-01

    Full Text Available The objective of this study was to evaluate the usefulness of comprehensive chromosome screening (CCS using array comparative genomic hybridization (aCGH. The study included 1420 CCS cycles for recurrent miscarriage (n=203; repetitive implantation failure (n=188; severe male factor (n=116; previous trisomic pregnancy (n=33; and advanced maternal age (n=880. CCS was performed in cycles with fresh oocytes and embryos (n=774; mixed cycles with fresh and vitrified oocytes (n=320; mixed cycles with fresh and vitrified day-2 embryos (n=235; and mixed cycles with fresh and vitrified day-3 embryos (n=91. Day-3 embryo biopsy was performed and analyzed by aCGH followed by day-5 embryo transfer. Consistent implantation (range: 40.5–54.2% and pregnancy rates per transfer (range: 46.0–62.9% were obtained for all the indications and independently of the origin of the oocytes or embryos. However, a lower delivery rate per cycle was achieved in women aged over 40 years (18.1% due to the higher percentage of aneuploid embryos (85.3% and lower number of cycles with at least one euploid embryo available per transfer (40.3%. We concluded that aneuploidy is one of the major factors which affect embryo implantation.

  18. Embryo development and corresponding factors affecting in vitro germination of Cymbidium faberi × C. sinense hybrid seeds

    OpenAIRE

    Li Fengtong; Bao Jianzhong; Sun Ye; Liu Chungui; Ma Hui; Zhang Tian; Chen Xiulan

    2016-01-01

    A better understanding of embryo development would provide insights into seed quality and subsequent germination events in the interspecific hybridization of Cymbidium faberi ‘Jiepeimei’ × C. sinense ‘Qijianheimo’. At the mature stage, 26.1% of the ovules were abnormal. Most of the hybrid embryos could develop normally. Abortions mainly occurred at the zygote (9.5%) and 2-4-celled embryo (15.1%) stages. No germination was observed at 90 and 105 days after p...

  19. Flat mount preparation for observation and analysis of zebrafish embryo specimens stained by whole mount in situ hybridization.

    Science.gov (United States)

    Cheng, Christina N; Li, Yue; Marra, Amanda N; Verdun, Valerie; Wingert, Rebecca A

    2014-07-17

    The zebrafish embryo is now commonly used for basic and biomedical research to investigate the genetic control of developmental processes and to model congenital abnormalities. During the first day of life, the zebrafish embryo progresses through many developmental stages including fertilization, cleavage, gastrulation, segmentation, and the organogenesis of structures such as the kidney, heart, and central nervous system. The anatomy of a young zebrafish embryo presents several challenges for the visualization and analysis of the tissues involved in many of these events because the embryo develops in association with a round yolk mass. Thus, for accurate analysis and imaging of experimental phenotypes in fixed embryonic specimens between the tailbud and 20 somite stage (10 and 19 hours post fertilization (hpf), respectively), such as those stained using whole mount in situ hybridization (WISH), it is often desirable to remove the embryo from the yolk ball and to position it flat on a glass slide. However, performing a flat mount procedure can be tedious. Therefore, successful and efficient flat mount preparation is greatly facilitated through the visual demonstration of the dissection technique, and also helped by using reagents that assist in optimal tissue handling. Here, we provide our WISH protocol for one or two-color detection of gene expression in the zebrafish embryo, and demonstrate how the flat mounting procedure can be performed on this example of a stained fixed specimen. This flat mounting protocol is broadly applicable to the study of many embryonic structures that emerge during early zebrafish development, and can be implemented in conjunction with other staining methods performed on fixed embryo samples.

  20. Induction and Histology of Primary and Secondary Somatic Embryos of Phalaenopsis Hybrid Classic Spotted Pink (Orquidaceae

    Directory of Open Access Journals (Sweden)

    Cláudia Ulisses de Carvalho Silva

    2016-09-01

    Full Text Available The present work had as objectives to induce the formation of somatic embryos in vitro on Phalaenopsis hybrid Classic Spotted Pink, using different nutrient medium and assess the internal morphology of these embryos by means of histological and histochemical analysis. Young leaves of plants grown in vitro were used as explants for induction of somatic embryos in different nutrient medium: New Dogashima Medium, containing ANA (0.537 mM and BAP (4.440 mM plus phytagel and with pH 5.8 (NDM and the Murashige & Skoog with half the concentration of salts, plus NNA (0.537 mM and TDZ (13.621 mM, jellied with gelrite and pH 5.2 (0.5 MS. Primary somatic embryos were obtained to 90 days of cultivation in half MS and have been transferred to the same means for obtaining of secondary embryos. The primary and secondary somatic embryos were subcultived for MS with half the concentration of salts, without fitoregulator subjected to photoperiod of 16 hours, which stimulated the production of chlorophyll in primary embryos as secondary, promoting the development of those in protocorms and later in plants. The histological analysis showed that the somatic embryos were formed directly from the epidermal layers of the explants, without going through the phase of callus, featuring direct somatic embryogenesis. The histochemical methods used made it possible to highlight the deposition of starch and lipids in cells embriogenics as a result of physiological mechanisms, enabling the development of primary and secondary embryos in plants. Therefore, the medium 0.5 MS Plus ANA (0.537 mM and TDZ (13.621 mM, jellied with gelrite and pH 5.2 promoted to obtain primary and secondary embryos with ability to regenerate plants showing morphological similar the mother plant.

  1. Detection of Embryo Sex Chromosome by Dual Color Fluorescent In-Situ Hybridization

    Institute of Scientific and Technical Information of China (English)

    刘群; 朱桂金

    2003-01-01

    Summary: In order to evaluate the effects of sex chromosomal mosaicism on the accuracy of single-cell gender diagnosis, sex chromosomes of 21 normal fertilized embryos were detected by dual colorfluorescent in-situ hybridization (FISH). The results showed that 4 embryos had sex chromosomalmosaicism (19%) and the remaining 17 showed uniformly XX or XY signals in all blastomeres. Inconclusion, identification of sex by dual color FISH analysis of a single cell was accurate and efficient,and sex chromosomal mosaicism would not affect preimplantation gender diagnosis.

  2. The embryo rescue derived intergeneric hybrid between chrysanthemum and Ajania przewalskii shows enhanced cold tolerance.

    Science.gov (United States)

    Deng, Yanming; Chen, Sumei; Chen, Fadi; Cheng, Xi; Zhang, Fei

    2011-12-01

    Five intergeneric hybrids between the chrysanthemum cultivar 'Zhongshanjingui' (as female) and Ajania przewalskii (as male) were obtained with the help of embryo culture. While 'Zhongshanjingui' bears a standard anemone type flower and A. przewalskii a non-anemone type one, the inflorescence type of the hybrids varied. The diameter of the hybrids' flowers was intermediate between those of the parents. The chromosome number of the hybrids was 2n = 45, of which GISH analysis was able to establish that 27 were inherited from 'Zhongshanjingui' and the other 18 from A. przewalskii. A combination of various assays was used to show that the cold tolerance of the hybrids was equivalent to that of the highly tolerant A. przewalskii parent. Enhanced cold tolerance was correlated with an increase in free proline and a decrease in malondialdehyde content.

  3. Embryo development and corresponding factors affecting in vitro germination of Cymbidium faberi × C. sinense hybrid seeds

    National Research Council Canada - National Science Library

    Li, Fengtong; Bao, Jianzhong; Sun, Ye; Liu, Chungui; Ma, Hui; Zhang, Tian; Chen, Xiulan

    2016-01-01

    A better understanding of embryo development would provide insights into seed quality and subsequent germination events in the interspecific hybridization of Cymbidium faberi ‘Jiepeimei’ × C. sinense ‘Qijianheimo...

  4. Differentially expressed genes implicated in embryo abortion of mango identified by suppression subtractive hybridization.

    Science.gov (United States)

    He, J H; Ma, F W; Chen, Y Y; Shu, H R

    2012-11-14

    Embryo abortion in mango severely damages mango production worldwide. The mechanisms by which the mango embryos abort have long been an intriguing question. We used subtractive suppression hybridization to investigate the differentially expressed genes involved in this process. We generated 2 cDNA libraries from normal seed and aborted seed embryos of mango cultivar 'Jinhuang'. One thousand five hundred and seventy-two high-quality expressed sequence tags (ESTs) were obtained, with 1092 from the normal seed tester library and 480 from the aborted seed tester library. These ESTs were assembled into 783 unigenes, including 147 contigs and 636 singletons in contigs; 297 singletons in gene ontology (GO) indicated coverage of a broad range of GO categories. Seven candidate genes from different categories were selected for semi-quantitative PCR analysis, and their possible functions in embryo abortion are discussed. These data provide new insight into the genetic regulation of embryo abortion in mango and may aid in further identification of novel genes and their functions.

  5. Ethical questions concerning research on human embryos, embryonic stem cells and chimeras.

    Science.gov (United States)

    Bobbert, Monika

    2006-12-01

    Research using human embryos and embryonic stem cells is viewed as important for various reasons. Apart from questions concerning legal regulations, numerous ethical objections are raised pertaining to the use of surplus embryos from reproductive medicine as well as the creation of embryos and stem cells through cloning. In the hopes of avoiding ethical problems, alternatives have been proposed including the extraction of egg cells from "dead" embryos derived from in vitro fertilization procedures, the extraction of pluripotent stem cells from blastocysts, technologies such as "altered nuclear transfer" (ANT) and "oocyte-assisted reprogramming" (ANT-OAR) as well as parthenogenesis. Initial ethical assessments show that certain questions pertaining to such strategies have remained unanswered. Furthermore, with the help of new or more differentiated biotechnological procedures, it is possible to create chimeras and hybrids in which human and non-human cells are combined. Human-animal chimeras, in which gametes or embryonic tissue have been mixed with embryonic or adult stem cells, demonstrate a different "quality" and "degree of penetration" from those produced in previous experiments. Not only does this have consequences regarding questions of patentability, this situation also raises fundamental questions concerning the human being's self image, the concept of person, identity and species and the moral rights and duties that are connected with such concepts. There is a need for legal regulation, on the national as well as the international level.

  6. The ethics of cloning and human embryo research.

    Science.gov (United States)

    Saran, Madeleine

    2002-01-01

    The successful cloning experiments that led to Dolly in 1997 have raised many ethical and policy questions. This paper will focus on cloning research in human embryonic cells. The possible gains of the research will be judged against the moral issues of doing research on a person. This paper concludes that while the embryo has some moral status, its moral status is outweighed by the multitude of benefits that embryonic stem cell research will bring to humanity. Policy suggestions are given for dealing with this new and developing field of stem cell research.

  7. Use of "excess" human embryos for stem cell research: protecting women's rights and health.

    Science.gov (United States)

    Cohen, C B

    2000-01-01

    Proposed National Institutes of Health guidelines for stem cell research are too narrowly drawn and do not adequately protect the freedom of choice and health of women who donate embryos. They need to be expanded to cover not only the point of embryo donation, but also that of embryo creation. Guidelines are provided to ensure that donors undergoing hyperstimulation and egg retrieval gave voluntary informed consent to the production of embryos that might later prove in excess. A standard for determining when embryos have been overproduced is presented to address the possibility that additional embryos will be created for stem cell research in violation of the guidelines and at risk to women's health.

  8. Early embryo and larval development of inviable intergeneric hybrids derived from Crassostrea angulata and Saccostrea cucullata

    Science.gov (United States)

    Su, Jiaqi; Wang, Zhaoping; Zhang, Yuehuan; Yan, Xiwu; Li, Qiongzhen; Yu, Ruihai

    2016-06-01

    To detect the intergeneric hybridization between the oyster Crassostrea angulata and Saccostrea cucullata coexisting along the southern coast of China, reciprocal crosses were conducted between the two species. Barriers for sperm recognizing, binding, penetrating the egg, and forming the pronucleus were detected by fluorescence staining. From the results, although fertilization success was observed in hybrid crosses, the overall fertilization rate was lower than that of intraspecific crosses. A large number of hybrid larvae died at 6-8 d after hatching, and those survived could not complete metamorphosis. C. angulata ♀× S. cucullata ♂ larvae had a growth rate similar to that of the maternal species, whereas S. cucullata ♀ × C. angulata ♂ larvae grew the slowest among all crosses. Molecular genetics analysis revealed that hybrid progeny were amphimixis hybrids. This study demonstrated that hybrid embryos generated by crossing C. angulata and S. cucullata could develop normally to the larval state, but could not complete metamorphosis and then develop to the spat stage. Thus, there is a post-reproductive isolation between C. angulata and S. cucullata.

  9. Embryo development and corresponding factors affecting in vitro germination of Cymbidium faberi × C. sinense hybrid seeds

    Directory of Open Access Journals (Sweden)

    Li Fengtong

    2016-01-01

    Full Text Available A better understanding of embryo development would provide insights into seed quality and subsequent germination events in the interspecific hybridization of Cymbidium faberi ‘Jiepeimei’ × C. sinense ‘Qijianheimo’. At the mature stage, 26.1% of the ovules were abnormal. Most of the hybrid embryos could develop normally. Abortions mainly occurred at the zygote (9.5% and 2-4-celled embryo (15.1% stages. No germination was observed at 90 and 105 days after pollination (DAP, when the embryo was at the early globular stage, with abundant organelles but no storage materials. During 110-130 DAP, the globular embryo was formed and the starch grains began to accumulate in plastids. The hybrid seeds collected at 120 DAP showed initiation of germination. Germination significantly increased at 135 DAP and was maximal at 150 DAP, during which period the hybrid embryos developed into the late globular stage. The storage materials, i.e. lipid and protein bodies, began to accumulate and the filamentary structures derived from suspensor cells still persisted. After the seeds matured (160 DAP, the germination percentage declined sharply. Safranin staining revealed that the outer seed coat was totally cuticularized and the inner seed coat appeared as a cuticle layer enclosing the embryo proper tightly, which may be the main factor inhibiting the subsequent germination of hybrid seeds. In conclusion, 150 DAP should be the opportune time for the in vitro germination of C. faberi ‘Jiepeimei’ × C. sinense ‘Qijianheimo’ hybrid seeds.

  10. Stem cell research on other worlds, or why embryos do not have a right to life.

    Science.gov (United States)

    Blackford, R

    2006-03-01

    Anxieties about the creation and destruction of human embryos for the purpose of scientific research on embryonic stem cells have given a new urgency to the question of whether embryos have moral rights. This article uses a thought experiment involving two possible worlds, somewhat removed from our own in the space of possibilities, to shed light on whether early embryos have such rights as a right not to be destroyed or discarded (a "right to life"). It is argued that early embryos do not have meaningful interests or any moral rights. Accordingly, claims about the moral rights of embryos do not justify restrictions on stem cell research.

  11. Research on Hybrid Vehicle Drivetrain

    Science.gov (United States)

    Xie, Zhongzhi

    Hybrid cars as a solution to energy saving, emission reduction measures, have received widespread attention. Motor drive system as an important part of the hybrid vehicles as an important object of study. Based on the hybrid electric vehicle powertrain control system for permanent magnet synchronous motor as the object of study. Can be applied to hybrid car compares the characteristics of traction motors, chose permanent magnet synchronous Motors as drive motors for hybrid vehicles. Building applications in hybrid cars in MATLAB/Simulink simulation model of permanent-magnet synchronous motor speed control system and analysis of simulation results.

  12. Comprehensive embryo analysis of advanced maternal age-related aneuploidies and mosaicism by short comparative genomic hybridization.

    Science.gov (United States)

    Rius, Mariona; Daina, Gemma; Obradors, Albert; Ramos, Laia; Velilla, Esther; Fernández, Sílvia; Martínez-Passarell, Olga; Benet, Jordi; Navarro, Joaquima

    2011-01-01

    The short comparative genomic hybridization (short-CGH) method was used to perform a comprehensive cytogenetic study of isolated blastomeres from advanced maternal age embryos, discarded after fluorescent in situ hybridization (FISH) preimplantation genetic screening (PGS), detecting aneuploidies (38.5% of which corresponded to chromosomes not screened by 9-chromosome FISH), structural aberrations (31.8%), and mosaicism (77.3%). The short-CGH method was subsequently applied in one PGS, achieving a twin pregnancy.

  13. Donating embryos for human embryonic stem cell (hESC) research: a committee opinion.

    Science.gov (United States)

    2013-10-01

    hESC research is an ethically acceptable use of human embryos that are in excess of those needed to meet the fertility goals of patients. The ethical basis for this view and issues to be considered during the informed consent process for the donation of embryos are developed in this document. This report replaces the Committee's 2009 report, "Donating spare embryos for stem cell research" (Fertil Steril 2009;91:667-70).

  14. Abnormalities occurring during female gametophyte development result in the diversity of abnormal embryo sacs and leads to abnormal fertilization in indica/japonica hybrids in rice.

    Science.gov (United States)

    Zeng, Yu-Xiang; Hu, Chao-Yue; Lu, Yong-Gen; Li, Jin-Quan; Liu, Xiang-Dong

    2009-01-01

    Embryo sac abortion is one of the major reasons for sterility in indica/japonica hybrids in rice. To clarify the causal mechanism of embryo sac abortion, we studied the female gametophyte development in two indica/japonica hybrids via an eosin B staining procedure for embryo sac scanning using confocal laser scanning microscope. Different types of abnormalities occurred during megasporogenesis and megagametogenesis were demonstrated. The earliest abnormality was observed in the megasporocyte. A lot of the chalazal-most megaspores were degenerated before the mono-nucleate embryo sac stage. Disordered positioning of nucleus and abnormal nucellus tissue were characteristics of the abnormal female gametes from the mono-nucleate to four-nucleate embryo sac stages. The abnormalities that occurred from the early stage of the eight-nucleate embryo sac development to the mature embryo sac stage were characterized by smaller sizes and wrinkled antipodals. Asynchronous nuclear migration, abnormal positioning of nucleus, and degeneration of egg apparatus were also found at the eight-nucleate embryo sac stage. The abnormalities that occurred during female gametophyte development resulted in five major types of abnormal embryo sacs. These abnormal embryo sacs led to abnormal fertilization. Hand pollination using normal pollens on the spikelets during anthesis showed that normal pollens could not exclude the effect of abnormal embryo sac on seed setting.

  15. Abnormalities Occurring during Female Gametophyte Development Result in the Diversity of Abnormal Embryo Sacs and Leads to Abnormal Fertilization in indicaljaponica Hybrids in Rice

    Institute of Scientific and Technical Information of China (English)

    Yu-Xiang Zeng; Chao-Yue Hu; Yong-Gen Lu; Jin-Quan Li; Xiang-Dong Liu

    2009-01-01

    Embryo sac abortion is one of the major masons for sterility in indicaljaponica hybrids In rice. To clarify the causal mechanism of embryo sac abortion, we studied the female gametophyte development in two indicaljaponica hybrids via an eosin B staining procedure for embryo sac scanning using confocal laser scanning microscope. Different types of abnormalities occurred during megasporogenesis and megagamatogenesis were demonstrated. The earliest abnormality was observed in the megasporocyte. A lot of the chalazal-most megaspores were degenerated before the mono-nucleate embryo sac stage. Disordered positioning of nucleus and abnormal nucallus tissue were characteristics of the abnormal female gametes from the mono-nucleate to four-nucleate embryo sac stages. The abnormalities that occurred from the early stage of the eight-nucleate embryo sac development to the mature embryo sac stage were characterized by smaller sizes and wrinkled antipodals. Asynchronous nuclear migration, abnormal positioning of nucleus, and degeneration of egg apparatus were also found at the eight-nucleate embryo sac stage. The abnormalities that occurred during female gametophyte development resulted in five major types of abnormal embryo sacs. These abnormal embryo sacs led to abnormal fertilization. Hand pollination using normal pollens on the spikelets during anthesis showed that normal pollens could not exclude the effect of abnormal embryo sac on seed setting.

  16. Embryo and endosperm development in caryopses of hybrids from crosses between tetraploid wheats and their alloplasmic lines with rye

    Directory of Open Access Journals (Sweden)

    Wijciech Sodkiewicz

    2014-01-01

    Full Text Available Data concerning the embryo and endosperm development in twenty-day-old caryopses of hybrids obtained as the result of pollination with rye pollen of tetraploid wheats (Triticum dicoccoides, T. dicoccum, T. durum and T. polonicum, their alloplasmic lines with T. timopheevi plasma and aIlaplasmic T. timopheevi lines with cytoplasma of the above mentioned tetraploid wheats and hexaploid wheat (T. macha were analysed. A high variability was noted between the tetraploid wheats as regards the degree of development of the embryo and of the endosperm in the hybrid caryopses and a decisive influence of the wheat genotype on these characters. The data for alloplasmic lines showed that the cytoplasm may have a modifying effect on the expression of these genotype characters.

  17. Development of resistant tomato population with bacterial canker resistance genes from interspecific hybrids by the support of embryo rescue

    Directory of Open Access Journals (Sweden)

    Aylin KABAŞ

    2016-06-01

    Full Text Available Bacterial canker is one of the most important diseases causing economic yield loss in tomato production areas in the world. The best way to control for this disease is to use resistant varieties. However, there are few studies on variety breeding studies of this disease compared with other disease resistant breeding studies. In this study we aimed to improve inbred lines carrying bacterial canker resistance genes to use in the breeding of resistant varieties. Susceptible inbred line AK1 (S. esculentum and resistant LA2157 (S. peruvianum were crossed. Embryo rescue and ovule culture techniques were applied in 30 fruits to get F1 hybrids. Rescued embryos and immature ovules were cultured in petri dishes containing solidified MS medium without hormone. 30 healty embryos were excised and cultured from 30 fruits 27-61 day old (1 embryo fruit-1 in embryo rescue method. The two surviving plants from acclimatization were transferred to the greenhouse to get their BC1 progenies. Resistance tests were performed according to the stem inoculation method in the BC1 and BC2 progenies. The mixture of 14 aggressive Turkish Cmm strains were used to confirm the resistance. The plants were valued by 0-4 scale. Plants with 0 and 1 scale values were used to obtain next progenies. A total of 80 BC3 resistant progenies were transferred to our variety breeding programme.

  18. Use of fluorescence in situ hybridization to assess the chromosomal status of embryos obtained from cryopreserved oocytes.

    Science.gov (United States)

    Cobo, A; Rubio, C; Gerli, S; Ruiz, A; Pellicer, A; Remohí, J

    2001-02-01

    To analyze the chromosomal status of human embryos obtained from frozen-thawed oocytes. Fluorescence in situ hybridization analysis of embryos obtained after oocyte cryopreservation. Department of Obstetrics and Gynecology at the University of Perugia, Italy, and the Instituto Valenciano de Infertilidad, Spain. Oocyte donors (n = 43). Fertilization, development, and chromosomal status of the embryos were compared with a control group (n = 18) of patients undergoing preimplantation genetic diagnosis for sex chromosome-linked diseases. Collection of oocytes after conventional ovarian stimulation and cryopreservation using propanediol as the cryoprotectant and a slow freezing procedure. Microinjection of surviving metaphase II oocytes and evaluation of fertilization and embryo development up to blastocyst stage. Chromosomal analysis after embryo biopsy. Survival, fertilization, and blastocyst rates. Embryo chromosomal analysis employing specific probes for chromosomes 13,18,21, X and Y. The overall survival rate was 59.4%. There was no difference between cryopreservation and control groups in fertilization rates (76.5% vs. 90.5%) or blastocyst development (29.6% vs. 35%). The percentage of blastocysts from the original number of cryopreserved oocytes was only 5.6%, comparable to the 5.9% obtained in the control group. The percentage of embryos with abnormal number of chromosomes in the cryopreservation group (28.6%) was comparable to the 26% observed in the controls. Fertilization and cleavage rates after oocyte freezing are acceptable. Survival is, however, still poor, leading to overall results that make the technique clinically inefficient. There is no increase in the rate of chromosomal abnormalities, indicating that the technique is, nevertheless, safe enough to be further explored and improved.

  19. Proteomic Analysis Reveals Different Involvement of Embryo and Endosperm Proteins during Aging of Yliangyou 2 Hybrid Rice Seeds

    Science.gov (United States)

    Zhang, Ying-Xue; Xu, Heng-Heng; Liu, Shu-Jun; Li, Ni; Wang, Wei-Qing; Møller, Ian M.; Song, Song-Quan

    2016-01-01

    Seed aging is a process that results in a delayed germination, a decreased germination percentage, and finally a total loss of seed viability. However, the mechanism of seed aging is poorly understood. In the present study, Yliangyou 2 hybrid rice (Oryza sativa L.) seeds were artificially aged at 100% relative humidity and 40°C, and the effect of artificial aging on germination, germination time course and the change in protein profiles of embryo and endosperm was studied to understand the molecular mechanism behind seed aging. With an increasing duration of artificial aging, the germination percentage and germination rate of hybrid rice seeds decreased. By comparing the protein profiles from the seeds aged for 0, 10 and 25 days, a total of 91 and 100 protein spots were found to show a significant change of more than 2-fold (P cell defense and rescue (28%), and with storage protein (18%). In endosperms, most of the identified proteins were involved in metabolism (37%), in energy (27%), and in protein synthesis and destination (11%). The most marked change was the increased abundance of many glycolytic enzymes together with the two fermentation enzymes pyruvate decarboxylase and alcohol dehydrogenase in the embryos during aging. We hypothesize that the decreased viability of hybrid rice seeds during artificial aging is caused by the development of hypoxic conditions in the embryos followed by ethanol accumulation.

  20. Researchers and firing squads: questions concerning the use of frozen human embryos.

    Science.gov (United States)

    Tully, Patrick

    2011-10-01

    Is it morally acceptable to use human embryos left over from fertility treatments in research that would harm or destroy them? Many answer "no" to this question on the grounds that all human beings, including human embryos, have a basic moral status that forbids such use. There are some, though, who accept this claim about the basic moral status of human embryos but who believe nevertheless that frozen human embryos which were generated for fertility treatments but which are no longer wanted for that project are a morally acceptable source of human embryonic stem cells and are acceptable subjects of other forms of research that would destroy them in course. The reasoning offered in defense of this position typically employs the claim that since these embryos are going to be discarded anyway, their possibly fruitful use by researchers is a preferable alternative and one that is not inconsistent with their basic moral status. Howard Curzer has offered a well-developed argument of this sort, defending the use of these embryos in the ways mentioned while at the same time allowing for their equal basic moral status. This article challenges Curzer's case and offers reasons to reject the moral acceptability of using even these to-be-discarded embryos as research material.

  1. Embryo research--why the Cardinal is wrong.

    Science.gov (United States)

    Walton

    1990-12-01

    Reasons are given for suggesting that individuation of the human embryo does not begin until the primitive streak forms at about the fourteenth day after conception; this view, though contested by many, is held by very many committed Christians of all denominations. In the conceptus or pre-embryo, after the formation of a blastocyst at about four-five days after fertilisation, biopsy of a single cell from the outer layer of cells (which later can form the membranes and placenta) can be used to determine the sex of the conceptus and will ultimately be used to detect the presence of an abnormal gene such as that for Duchenne-type muscular dystrophy, without detriment to development of the basal cell mass from which the embryo forms. The potential benefits in the prevention of inherited disease are profound.

  2. Political interventions in U.S. human embryo research: an ethical assessment.

    Science.gov (United States)

    Green, Ronald M

    2010-01-01

    For more than 30 years, beginning with the Reagan administration's refusal to support and provide oversight for embryo research, and continuing to the present in congressionally imposed limits on funding for such research, progress in infertility medicine and the development of stem cell therapies has been seriously delayed by a series of political interventions. In almost all cases, these interventions result from a view of the moral status of human embryo premised largely on religious assumptions. Although some believe that these interventions are valid expressions of religious values in the public sector, it is argued here that they, in fact, contradict Rawls's conception of public reasoning. Both the prohibition of research involving the human embryo as well as bans on federal funding for embryo-related research place the particular religious views of some citizens above the pressing health needs of almost all, and thus violate the ideal of civility implicit in the Rawlsian standard.

  3. Fresh or frozen? Classifying 'spare' embryos for donation to human embryonic stem cell research.

    Science.gov (United States)

    Ehrich, Kathryn; Williams, Clare; Farsides, Bobbie

    2010-12-01

    United Kingdom (UK) funding to build human embryonic stem cell (hESC) derivation labs within assisted conception units (ACU) was intended to facilitate the 'In-vitro fertilisation (IVF)-stem cell interface', including the flow of fresh 'spare' embryos to stem cell labs. However, in the three sites reported on here, which received this funding, most of the embryos used for hESC research came from long term cryopreservation storage and/or outside clinics. In this paper we explore some of the clinical, technical, social and ethical factors that might help to explain this situation. We report from our qualitative study of the ethical frameworks for approaching women/couples for donation of embryos to stem cell research. Members of staff took part in 44 interviews and six ethics discussion groups held at our study sites between February 2008 and October 2009. We focus here on their articulations of social and ethical, as well as scientific, dimensions in the contingent classification of 'spare' embryos, entailing uncertainty, fluidity and naturalisation in classifying work. Social and ethical factors include acknowledging and responding to uncertainty in classifying embryos; retaining 'fluidity' in the grading system to give embryos 'every chance'; tensions between standardisation and variation in enacting a 'fair' grading system; enhancement of patient choice and control, and prevention of regret; and incorporation of patients' values in construction of ethically acceptable embryo 'spareness' ('frozen' embryos, and embryos determined through preimplantation genetic diagnosis (PGD) to be genetically 'affected'). We argue that the success of the 'built moral environment' of ACU with adjoining stem cell laboratories building projects intended to facilitate the 'IVF-stem cell interface' may depend not only on architecture, but also on the part such social and ethical factors play in configuration of embryos as particular kinds of moral work objects.

  4. The moral status of the embryo: the human embryo in the UK Human Fertilisation and Embryology (Research Purposes) Regulation 2001 debate.

    Science.gov (United States)

    Bahadur, G

    2003-01-01

    The use of the embryo in research into birth defects, infertility and the possible therapeutic value of embryonic stem cells, has given rise to vigorous discussion of the ethical, moral and legal status of the embryo. This paper considers the parliamentary debate that surrounded the passing of legislation in the UK in 2000 governing the use of the embryo in research. Underlying disagreement by members of Parliament as to whether embryo research was permissible, were considerable differences regarding when life was thought to begin--whether at the moment of fertilization of the egg, or whether after 14 days, at the time of the beginnings of cell differentiation, and the point after which the embryo can no longer split to form twins. Those who favoured the latter view argued that, while the conceptus might possess a unique genetic formula, it had only the potential for life before 14 days, the development of human life being a gradual and continuous process. They considered it mistaken to accord the embryo full human rights. Those who adopted an opposed standpoint insisted that life was present and actual from the moment of conception and therefore sacrosanct and inviolable. The notion of the pre-embryo, they maintained, merely serves to disguise the embryo's humanity.

  5. Reporting of embryo transfer methods in IVF research: a cross-sectional study.

    Science.gov (United States)

    Gambadauro, Pietro; Navaratnarajah, Ramesan

    2015-02-01

    The reporting of embryo transfer methods in IVF research was assessed through a cross-sectional analysis of randomized controlled trials (RCTs) published between 2010 and 2011. A systematic search identified 325 abstracts; 122 RCTs were included in the study. Embryo transfer methods were described in 42 out of 122 articles (34%). Catheters (32/42 [76%]) or ultrasound guidance (31/42 [74%]) were most frequently mentioned. Performer 'blinding' (12%) or technique standardization (7%) were seldom reported. The description of embryo transfer methods was significantly more common in trials published by journals with lower impact factor (less than 3, 39.6%; 3 or greater, 21.5%; P = 0.037). Embryo transfer methods were reported more often in trials with pregnancy as the main end-point (33% versus 16%) or with positive outcomes (37.8% versus 25.0%), albeit not significantly. Multivariate logistic regression confirmed that RCTs published in higher impact factor journals are less likely to describe embryo transfer methods (OR 0.371; 95% CI 0.143 to 0.964). Registered trials, trials conducted in an academic setting, multi-centric studies or full-length articles were not positively associated with embryo transfer methods reporting rate. Recent reports of randomized IVF trials rarely describe embryo transfer methods. The under-reporting of research methods might compromise reproducibility and suitability for meta-analysis.

  6. Comparative proteomic analysis of embryos between a maize hybrid and its parental lines during early stages of seed germination.

    Directory of Open Access Journals (Sweden)

    Baojian Guo

    Full Text Available In spite of commercial use of heterosis in agriculture, the molecular basis of heterosis is poorly understood. It was observed that maize hybrid Zong3/87-1 exhibited an earlier onset or heterosis in radicle emergence. To get insights into the underlying mechanism of heterosis in radicle emergence, differential proteomic analysis between hybrid and its parental lines was performed. In total, the number of differentially expressed protein spots between hybrid and its parental lines in dry and 24 h imbibed seed embryos were 134 and 191, respectively, among which 47.01% (63/134 and 34.55% (66/191 protein spots displayed nonadditively expressed pattern. Remarkably, 54.55% of nonadditively accumulated proteins in 24 h imbibed seed embryos displayed above or equal to the level of the higher parent patterns. Moreover, 155 differentially expressed protein spots were identified, which were grouped into eight functional classes, including transcription & translation, energy & metabolism, signal transduction, disease & defense, storage protein, transposable element, cell growth & division and unclassified proteins. In addition, one of the upregulated proteins in F1 hybrids was ZmACT2, a homolog of Arabidopsis thaliana ACT7 (AtACT7. Expressing ZmACT2 driven by the AtACT7 promoter partially complemented the low germination phenotype in the Atact7 mutant. These results indicated that hybridization between two parental lines can cause changes in the expression of a variety of proteins, and it is concluded that the altered pattern of gene expression at translational level in the hybrid may be responsible for the observed heterosis.

  7. A Research on Airborne Squint Hybrid SAR

    Institute of Scientific and Technical Information of China (English)

    BIANYong; ZHOUYinqing; LIChunsheng

    2004-01-01

    In this paper, we establish the squint mode hybrid SAR (Synthetic aperture radar) geometry. Based on the squint mode SAR geometry, the hybrid SAR signal model in squint case is derived. Based on this signal model, the hybrid SAR imaging process parameter is discussed. Aimed at the squint case, we analyze not only the relationship between the resolution and SAR system parameters, but also the relation between the time extension of the maximum azimuth signal and SAR system parameters. This research establishes the theoretical foundation for the design of squint hybrid SAR and serves as a good guide for the future work of improving the resolution of squint hybrid SAR. Based on the two-step algorithm, by considering the squint angle and cubic phase term, we are going to use the deramp SC-Chirp Scaling algorithm for squint hybrid SAR imaging. This algorithm uses the deramp method for the first step processing, and the SC-Chirp Scaling algorithm for the second step processing. The process procedure of this algorithm includes the squint angle, has the explicit physical meaning, therefore is convenient for analysis. The computer simulation result proves the validity of the analysis.

  8. Human cloning and embryo research: the 2003 John J. Conley Lecture on medical ethics.

    Science.gov (United States)

    George, Robert P

    2004-01-01

    The author, a member of the U.S. President's Council on Bioethics, discusses ethical issues raised by human cloning, whether for purposes of bringing babies to birth or for research purposes. He first argues that every cloned human embryo is a new, distinct, and enduring organism, belonging to the species Homo sapiens, and directing its own development toward maturity. He then distinguishes between two types of capacities belonging to individual organisms belonging to this species, an immediately exerciseable capacity and a basic natural capacity that develops over time. He argues that it is the second type of capacity that is the ground for full moral respect, and that this capacity (and its concomitant degree of respect) belongs to cloned human embryos no less than to adult human beings. He then considers and rejects counter-arguments to his position, including the suggestion that the capacity of embryos is equivalent to the capacity of somatic cells, that full human rights are afforded only to human organisms with functioning brains, that the possibility of twinning diminishes the moral status of embryos, that the fact that people do not typically mourn the loss of early embryos implies that they have a diminished moral status, that the fact that early spontaneous abortions occur frequently diminishes the moral status of embryos, and that his arguments depend upon a concept of ensoulment. He concludes that if the moral status of cloned human embryos is equivalent to that of adults, then public policy should be based upon this assumption.

  9. Ultralight Solar Powered Hybrid Research Drone

    CERN Document Server

    Singer, Csaba

    2013-01-01

    A planetary research drone is proposed, which is capable for vertical takeoff and landing. A hybrid flight concept utilizing static lift enables the exploration over ground. The static lift is achieved with a lighter than CO2 gas like air, He or H2.

  10. Attitudes of patients, healthcare professionals and ethicists towards embryonic stem cell research and donation of gametes and embryos in Germany.

    Science.gov (United States)

    Krones, T; Neuwohner, E; Bock, K; Manolopoulos, K; Tinneberg, H R; Richter, G

    2006-11-01

    Due to the Embryo Protection Act, creation of supernumerary embryos, as well as egg and embryo donation, is prohibited in Germany. Human stem cell research is regulated through the Act on stem cells that came into force in 2002. A cross-sectional survey of 101 IVF couples (n=202) in two fertility centres, and representative samples of healthcare professionals and ethicists (n=879), was carried out, and their attitudes towards embryonic stem cell research and donation of gametes and embryos compared. A clear majority of IVF couples favoured legalization of egg and embryo donation and embryonic stem cell research for various purposes. The willingness of couples to donate was related to purpose and to other independent influences. The majority of physicians voted for legalization of embryonic stem cell production from surplus embryos. Most human geneticists and obstetricians approved egg, but not embryo, donation to other couples. Ethicists and midwives were opposed to every kind of donation and research on surplus embryos. The IVF couples surveyed have positive attitudes towards donation and research using surplus embryos, whereas the healthcare professionals and ethicists are predominantly sceptical about most research activities destroying human embryos. This difference should be considered carefully in legal and ethical discussions on reprogenetics.

  11. Pollen Viability, Pistil Receptivity, and Embryo Development in Hybridization of Nelumbo nucifera Gaertn

    Directory of Open Access Journals (Sweden)

    Yan-Li Wang

    2012-01-01

    Full Text Available Seed set is usually low and differs for different crosses of flower lotus (Nelumbo nucifera Gaertn.. The reasons remain unknown, and this has a negative impact on lotus breeding. To determine the causes, we carried out two crosses of flower lotus, that is, “Jinsenianhua” × “Qinhuaihuadeng” and “Qinhuaihuadeng” × “Jinsenianhua” and pollen viability, pistil receptivity, and embryo development were investigated. The pollen grains collected at 05:00-06:00 hrs had the highest viability, and the viabilities of “Jinsenianhua” and “Qinhuaihuadeng” were 20.6 and 15.7%, respectively. At 4 h after artificial pollination, the number of pollen grains germinating on each stigma reached a peak: 63.0 and 17.2 per stigma in “Jinsenianhua” × “Qinhuaihuadeng” and “Qinhuaihuadeng” × “Jinsenianhua”, respectively. At 1 d after artificial pollination, the percentages of normal embryos in the two crosses were 55.0 and 21.9%, respectively; however, at 11 d after pollination, the corresponding percentages were 20.8 and 11.2%. Seed sets of the two crosses were 17.9 and 8.0%, respectively. The results suggested that low pistil receptivity and embryo abortion caused low seed set in “Qinhuaihuadeng” × “Jinsenianhua”, whereas low fecundity of “Jinsenianhua” × “Qinhuaihuadeng” was mainly attributable to embryo abortion.

  12. Research on Growth Behavior of Embryos for Bovine and Murine on Primary Murine Embryos Fibroblast Cell Feeder Layer

    Institute of Scientific and Technical Information of China (English)

    AN Li-long; XIAO Mei; FENG Xiu-Liang; DOU Zhong-ying; QIU Huai; YANG Qi; LEI An-min; YANG Chun-rong; GAO Zhi-min

    2002-01-01

    The difference in growth behavior between bovine embryos and murine embryos was studied on PMEF(primary murine embryos fibroblast)feeder layer. The results showed as follows: With embryos having attached, bovine embryonic trophoblast formed a transparent membranous structure covering on inner cell mass (ICM), however, murine embryonic trophoblast formed disc structure. Bovine embryos formed four kinds of ICM colonies with different morphology including the mass-like, the net-like, the stream-like and the mixture-like colonies. Compared with Murine ICM, the bovine ICM grew more fast. So, the bovine ICM was passaged at first after a culture of approximately 5 - 6 days in vitro, but murine ICM was passaged at first after an attachment of 3 - 4 days on PMEF feeder layer. The mixture colonies of bovine ICM differentiated very early, while the others differentiated very late. Most ICM-like mass of Bovine grew in a defined spot, but bovine ICMs like stream and ICMs like net proliferated fast and dispersed quickly. We found that the single blastomeres derived from late bovine morula and late murine morula formed sub-blastophere; moreover, the bovine ICM cell would differentiate rapidly if the trophoblast was removed.

  13. Ethical and policy issues surrounding the donation of cryopreserved and fresh embryos for human embryonic stem cell research.

    Science.gov (United States)

    Cohen, Cynthia B

    2009-06-01

    The use of human embryos in human embryonic stem cell (hESC) research raises significant ethical and policy issues associated with their donation. Recent research conducted in several countries assesses the percent of persons with cryopreserved and fresh supernumerary embryos willing to donate them for research, their reasons for considering this option, and the concerns they raise about its personal import. Such research provides new insights into rising ethical and policy questions associated with embryo donation for hESC research that should be addressed. In response to such questions, it is argued here that consent to the donation of supernumerary embryos for hESC research should be sought in two or three stages, depending on whether fresh or frozen embryos are at issue, in order to provide patients and their partners with sufficient time and information before they make a final decision. In addition, steps should be taken to support the voluntariness of their decisions by having personnel other than the treating reproductive specialist or stem cell investigators solicit their consent. Prospective embryo donors should also be given a choice about the uses to which hESCs derived from their donated embryos will be put in order to honor their ethical convictions and ensure that there are sufficient embryos for this research. The well-being and rights of those who donate embryos for this research require the sort of support and protection that can be provided by an ethical and policy framework that allows hESC investigations to move forward according to standards that are transparent and that resound with public values.

  14. Hybrid vigor, fetal overgrowth, and viability of mice derived by nuclear cloning and tetraploid embryo complementation.

    Science.gov (United States)

    Eggan, K; Akutsu, H; Loring, J; Jackson-Grusby, L; Klemm, M; Rideout, W M; Yanagimachi, R; Jaenisch, R

    2001-05-22

    To assess whether heterozygosity of the donor cell genome was a general parameter crucial for long-term survival of cloned animals, we tested the ability of embryonic stem (ES) cells with either an inbred or F(1) genetic background to generate cloned mice by nuclear transfer. Most clones derived from five F(1) ES cell lines survived to adulthood. In contrast, clones from three inbred ES cell lines invariably died shortly after birth due to respiratory failure. Comparison of mice derived from nuclear cloning, in which a complete blastocyst is derived from a single ES cell, and tetraploid blastocyst complementation, in which only the inner cell mass is formed from a few injected ES cells, allows us to determine which phenotypes depend on the technique or on the characteristics of the ES cell line. Neonatal lethality also has been reported in mice entirely derived from inbred ES cells that had been injected into tetraploid blastocysts (ES cell-tetraploids). Like inbred clones, ES cell-tetraploid pups derived from inbred ES cell lines died shortly after delivery with signs of respiratory distress. In contrast, most ES cell-tetraploid neonates, derived from six F(1) ES cell lines, developed into fertile adults. Cloned pups obtained from both inbred and F(1) ES cell nuclei frequently displayed increased placental and birth weights whereas ES cell-tetraploid pups were of normal weight. The potency of F(1) ES cells to generate live, fertile adults was not lost after either long-term in vitro culture or serial gene targeting events. We conclude that genetic heterozygosity is a crucial parameter for postnatal survival of mice that are entirely derived from ES cells by either nuclear cloning or tetraploid embryo complementation. In addition, our results demonstrate that tetraploid embryo complementation using F(1) ES cells represents a simple, efficient procedure for deriving animals with complex genetic alterations without the need for a chimeric intermediate.

  15. Research and application of hybrid wheat in China

    Institute of Scientific and Technical Information of China (English)

    Zhao Changping

    2013-01-01

    Hybrid wheat is recognized as a preferred approach to improve wheat yield,and it will be a competi-tion focus in high-tech seed industry in the future. We have made a breakthrough for the first time in creation of two-line hybrid wheat system,which reaches the world leading level in wheat research and has laid an important foundation for the future direction of the world wheat research. Similar to hybrid rice,the innovation of two-line hybrid wheat system is another achievement in science and technology. The application of hybrid wheat in China will greatly increase the food production,and make a great significance to food production and food security. This paper introduces the development process and major breakthrough of hybrid wheat in China,and the main bottle-neck and countermeasures in the application of hybrid wheat.

  16. Hybrid soft computing approaches research and applications

    CERN Document Server

    Dutta, Paramartha; Chakraborty, Susanta

    2016-01-01

    The book provides a platform for dealing with the flaws and failings of the soft computing paradigm through different manifestations. The different chapters highlight the necessity of the hybrid soft computing methodology in general with emphasis on several application perspectives in particular. Typical examples include (a) Study of Economic Load Dispatch by Various Hybrid Optimization Techniques, (b) An Application of Color Magnetic Resonance Brain Image Segmentation by ParaOptiMUSIG activation Function, (c) Hybrid Rough-PSO Approach in Remote Sensing Imagery Analysis,  (d) A Study and Analysis of Hybrid Intelligent Techniques for Breast Cancer Detection using Breast Thermograms, and (e) Hybridization of 2D-3D Images for Human Face Recognition. The elaborate findings of the chapters enhance the exhibition of the hybrid soft computing paradigm in the field of intelligent computing.

  17. Parental exposure to environmental concentrations of diuron leads to aneuploidy in embryos of the Pacific oyster, as evidenced by fluorescent in situ hybridization

    Energy Technology Data Exchange (ETDEWEB)

    Barranger, Audrey, E-mail: audrey.barranger@ifremer.fr [Ifremer, SG2M, Laboratory of Genetics and Pathology of Marine Molluscs, Avenue de Mus du Loup, 17390 La Tremblade (France); Ifremer, Department of Biogeochemistry and Ecotoxicology, Laboratory of Ecotoxicology, Rue de l’Ile d’Yeu, BP 21105, 44311 Nantes Cedex 03 (France); Benabdelmouna, Abdellah, E-mail: abdellah.benabdelmouna@ifremer.fr [Ifremer, SG2M, Laboratory of Genetics and Pathology of Marine Molluscs, Avenue de Mus du Loup, 17390 La Tremblade (France); Dégremont, Lionel [Ifremer, SG2M, Laboratory of Genetics and Pathology of Marine Molluscs, Avenue de Mus du Loup, 17390 La Tremblade (France); Burgeot, Thierry; Akcha, Farida [Ifremer, Department of Biogeochemistry and Ecotoxicology, Laboratory of Ecotoxicology, Rue de l’Ile d’Yeu, BP 21105, 44311 Nantes Cedex 03 (France)

    2015-02-15

    Highlights: • FISH was realized on oyster embryos from diuron-exposed genitors. • rDNA genes were used as probes on the interphase nuclei of embryo preparations. • Higher aneuploidy level was observed in embryos from diuron-exposed genitors. • Hypo- and hyperdiploid (triploid) nuclei were detected. - Abstract: Changes in normal chromosome numbers (i.e. aneuploidy) due to abnormal chromosome segregation may arise either spontaneously or as a result of chemical/radiation exposure, particularly during cell division. Coastal ecosystems are continuously subjected to various contaminants originating from urban, industrial and agricultural activities. Genotoxicity is common to several families of major environmental pollutants, including pesticides, which therefore represent a potential important environmental hazard for marine organisms. A previous study demonstrated the vertical transmission of DNA damage by subjecting oyster genitors to short-term exposure to the herbicide diuron at environmental concentrations during gametogenesis. In this paper, Fluorescent in situ hybridization (FISH) was used to further characterize diuron-induced DNA damage at the chromosomal level. rDNA genes (5S and 18-5.8-28S), previously mapped onto Crassostrea gigas chromosomes 4, 5 and 10, were used as probes on the interphase nuclei of embryo preparations. Our results conclusively show higher aneuploidy (hypo- or hyperdiploidy) level in embryos from diuron-exposed genitors, with damage to the three studied chromosomal regions. This study suggests that sexually developing oysters are vulnerable to diuron exposure, incurring a negative impact on reproductive success and oyster recruitment.

  18. Production, morphology, and cytogenetics of Triticum aestivum (L.) Thell × Elymus scabrus (R. Br.) Love intergeneric hybrids obtained by in ovulo embryo culture.

    Science.gov (United States)

    Ahmad, F; Comeau, A

    1991-06-01

    Intergeneric hybrids were produced between common wheat, Triticum aestivum (2n=6x=42, AABBDD), and an apomictic Triticeae species, Elymus scabrus (syn. Agropyron scabrum) (2n=6x=42, HHSSSS), the first successful report of this cross. Nine tiny, underdeveloped, and structureless embryos were obtained in vitro only by in ovulo embryo culture at 4 days after pollination, which gave rise to five mature hybrid plants. All the hybrid plants were vigorous and possessed a phenotype intermediate to the two parents. There were 2n=6x=42 (ABDHSS) somatic chromosomes in the hybrids. There was little or no homology between the parental genomes, as shown by an overall meiotic chromosome association of 32.83 I + 4.08 rod II + 0.21 ring II + 0.18 III + 0.02 IV. The hybrids were completely sterile and so far backcrosses to wheat parent have not been successful. Alternate approaches to induce gene transfer(s) from E. scabrus to wheat are being attempted.

  19. Recovery of citrus triploid hybrids by embryo rescue and flow cytometry from 2x x 2x sexual hybridisation and its application to extensive breeding programs.

    Science.gov (United States)

    Aleza, P; Juárez, J; Cuenca, J; Ollitrault, P; Navarro, Luis

    2010-09-01

    Seedlessness is one of the most important characteristics for mandarins for the fresh-fruit market and mandarin triploid hybrids have this trait. Citrus triploid plants can be recovered by 2x x 2x sexual hybridisations as a consequence of the formation of unreduced gametes at low frequency. Triploid embryos are found in small seeds that do not germinate under greenhouse conditions. Extensive breeding programs based on this type of hybridisation require very effective methodologies for embryo rescue and ploidy evaluation. In this work, we describe an effective methodology to recover triploid hybrids from 2x x 2x hybridisations based on in vitro embryo rescue and ploidy level determination by means of flow cytometry. The influence of parents and environmental conditions on obtaining triploid hybrids has been analysed. The strongest effect was associated with the genotype of the female parent while a strong interaction was found between the male parent genotype and environmental conditions. The effect of the female parent genotype on the length of the juvenile phase was also demonstrated by observing a large number of progenies over the last 10 years. The methodology described here has enabled us to obtain over 4,000 triploid hybrids so far, of which 13 have been protected in the European Union and two are being extensively planted by citrus growers to establish new commercial plots. These triploid hybrids have been analysed with simple sequence repeats markers to differentiate all the new triploid varieties and their parents, and thus molecular identification will help defend plant breeders' rights.

  20. Preferential recruitment of the maternal centromere-specific histone H3 (CENH3) in oat (Avena sativa L.) × pearl millet (Pennisetum glaucum L.) hybrid embryos.

    Science.gov (United States)

    Ishii, Takayoshi; Sunamura, Naohiro; Matsumoto, Ayaka; Eltayeb, Amin Elsadig; Tsujimoto, Hisashi

    2015-12-01

    Chromosome elimination occurs frequently in interspecific hybrids between distantly related species in Poaceae. However, chromosomes from both parents behave stably in a hybrid of female oat (Avena sativa L.) pollinated by pearl millet (Pennisetum glaucum L.). To analyze the chromosome behavior in this hybrid, we cloned the centromere-specific histone H3 (CENH3) genes of oat and pearl millet and produced a pearl millet-specific anti-CENH3 antibody. Application of this antibody together with a grass species common anti-CENH3 antibody revealed the dynamic CENH3 composition of the hybrid cells before and after fertilization. Despite co-expression of CENH3 genes encoded by oat and pearl millet, only an oat-type CENH3 was incorporated into the centromeres of both species in the hybrid embryo. Oat CENH3 enables a functional centromere in pearl millet chromosomes in an oat genetic background. Comparison of CENH3 genes among Poaceae species that show chromosome elimination in interspecific hybrids revealed that the loop 1 regions of oat and pearl millet CENH3 exhibit exceptionally high similarity.

  1. Influences of different factors on the germination of encapsulated somatic embryos of Saccharum spp hybrid var C 87-51

    Directory of Open Access Journals (Sweden)

    Elisa Quiala

    2001-04-01

    Full Text Available With the objective to regenerate plants from sugarcane somatic embryos encapsulated in sodium alginate hidrogel different factors was studied. The addition of coconut water, GA3 (0.5 mg.l-1 and 6-BAP (0.2 mg.l-1 to the synthetic endosperm increased the velocity and germination percentage of somatic embryos encapsulated. The immersion treatment in 50mM solution of KNO3 during five hours improved the encapsulated somatic embryos germination percentage. ABBREVIATOR: AG3- Giberelic Acid; 6-BAP- 6-Bencilaminopurine; MS- Murashige and Skoog (1962 Key Words: sodium alginate, sugar cane, synthetic seed

  2. 鸡与鹌鹑属间杂交早期胚胎性别的DNA分子鉴定%DNA Molecular Sex Identification for Chicken(Gallus gallus)-quail (Coturnix coturnix) Hybrids Early Embryos

    Institute of Scientific and Technical Information of China (English)

    郑炜; 范丽娜; 翟曼君; 赵宗胜; 李青峰; 梁耀伟; 米拉

    2013-01-01

    According to our previous research, there was an obvious relationship between the early death of chicken(Gallus gallus)-quail(Cotumix cotunux) hybrids and sex differentiation. Meanwhile, current widespread adapted methods to indentify sex differentiation stayed at RNA level, experimental steps complicated and easy to make mistakes, and RNA samples, which are needed to be measured, was quite difficult to preserved longer, but could not be simply employed. So it is necessary to find a more simple and accurate way to identify the early embryo's sexing. In this study, there were two sections for CHD (chromobox-helicase-DNA binding) gene DNA level sex determination, at first,a total of 116 chicken-quail hybrid embryos at different incubate stages (2.5~5 d) was treated as experiment group and 10 mg embryonic organs were used to DNA extraction; then the DNA extraction from blood of 60 sex-known quails (male and female were half-and-half) was regarded as control. Wpkci (W-linked protein kinase C inhibitor) for mRNA level was known as a mature method to identify sexing, and then it is used to check the result of embryos' sex determination in our research. The result showed that CHD 2550F/2718R could identify the sex of chicken-quail hybrid embryos accurately. The amplication size of male embryo tissues was 613 bp and two bands in female were 613 and 446 bp, respectively. The experimental results provide basic data for the chicken-quail hybrids sex determination mechanism.%鸡(Gallus gallus)与鹌鹑(Coturnix coturnix)属间杂交胚胎早期死亡与性别分化存在着一定的关系,寻找简单、准确的早期胚胎性别鉴定方法是深入研究其死亡分子机制的前提.本实验室前期使用Wpkci引物从mRNA水平对早期胚胎进行准确的性别鉴定,而RNA提取对样品质量要求较高,鉴定程序较复杂.因此需要建立更加简单快捷的方法,对鸡与鹌鹑属间杂交早期胚胎进行准确性别鉴定.本

  3. Are human embryos Kantian persons?: Kantian considerations in favor of embryonic stem cell research.

    Science.gov (United States)

    Manninen, Bertha Alvarez

    2008-01-31

    One argument used by detractors of human embryonic stem cell research (hESCR) invokes Kant's formula of humanity, which proscribes treating persons solely as a means to an end, rather than as ends in themselves. According to Fuat S. Oduncu, for example, adhering to this imperative entails that human embryos should not be disaggregated to obtain pluripotent stem cells for hESCR. Given that human embryos are Kantian persons from the time of their conception, killing them to obtain their cells for research fails to treat them as ends in themselves. This argument assumes two points that are rather contentious given a Kantian framework. First, the argument assumes that when Kant maintains that humanity must be treated as an end in itself, he means to argue that all members of the species Homo sapiens must be treated as ends in themselves; that is, that Kant regards personhood as co-extensive with belonging to the species Homo sapiens. Second, the argument assumes that the event of conception is causally responsible for the genesis of a Kantian person and that, therefore, an embryo is a Kantian person from the time of its conception. In this paper, I will present challenges against these two assumptions by engaging in an exegetical study of some of Kant's works. First, I will illustrate that Kant did not use the term "humanity" to denote a biological species, but rather the capacity to set ends according to reason. Second, I will illustrate that it is difficult given a Kantian framework to denote conception (indeed any biological event) as causally responsible for the creation of a person. Kant ascribed to a dualistic view of human agency, and personhood, according to him, was derived from the supersensible capacity for reason. To argue that a Kantian person is generated due to the event of conception ignores Kant's insistence in various aspects of his work that it is not possible to understand the generation of a person qua a physical operation. Finally, I will end the

  4. Are human embryos Kantian persons?: Kantian considerations in favor of embryonic stem cell research

    Directory of Open Access Journals (Sweden)

    Manninen Bertha

    2008-01-01

    Full Text Available Abstract One argument used by detractors of human embryonic stem cell research (hESCR invokes Kant's formula of humanity, which proscribes treating persons solely as a means to an end, rather than as ends in themselves. According to Fuat S. Oduncu, for example, adhering to this imperative entails that human embryos should not be disaggregated to obtain pluripotent stem cells for hESCR. Given that human embryos are Kantian persons from the time of their conception, killing them to obtain their cells for research fails to treat them as ends in themselves. This argument assumes two points that are rather contentious given a Kantian framework. First, the argument assumes that when Kant maintains that humanity must be treated as an end in itself, he means to argue that all members of the species Homo sapiens must be treated as ends in themselves; that is, that Kant regards personhood as co-extensive with belonging to the species Homo sapiens. Second, the argument assumes that the event of conception is causally responsible for the genesis of a Kantian person and that, therefore, an embryo is a Kantian person from the time of its conception. In this paper, I will present challenges against these two assumptions by engaging in an exegetical study of some of Kant's works. First, I will illustrate that Kant did not use the term "humanity" to denote a biological species, but rather the capacity to set ends according to reason. Second, I will illustrate that it is difficult given a Kantian framework to denote conception (indeed any biological event as causally responsible for the creation of a person. Kant ascribed to a dualistic view of human agency, and personhood, according to him, was derived from the supersensible capacity for reason. To argue that a Kantian person is generated due to the event of conception ignores Kant's insistence in various aspects of his work that it is not possible to understand the generation of a person qua a physical

  5. Direction and Policies Needed to Support Hybrid Electric Car Research

    Directory of Open Access Journals (Sweden)

    Ridwan Arief Subekti

    2012-07-01

    Full Text Available The rising number of vehicles over the years has driven the increase of air pollution and fuel consumption. One of the solutions to overcome this problem is using hybrid electric car because it is environmentally friendly and efficient in fuel consumption. LIPI has conducted electric car research since 1997, but there were so many problems in its development that electric car can not be developed into a national industry scale. Therefore, it is important to conduct a study that maps the problems and finds the solutions to prevent the same failure of electric car commercialization process from happening to hybrid electric car . This study was done by collecting and analyzing the primary and secondary data through interviews, discussing electric hybrid car with stakeholders, and examining earlier study results and regulations. Based on this study, several policies to support sustainability research of hybrid electric car were proposed. Some recommendations were the making of national roadmap and regulation for the usage of hybrid electric car on the road. For policy makers at LIPI, a research focus, research coordination, and pre-commercialization program were recommended.

  6. On Women, Egg Cells and Embryos Gender in the Regulatory Debates on Embryonic Research in the Netherlands

    NARCIS (Netherlands)

    Kirejczyk, Marta

    2008-01-01

    In contrast to many countries, the political debates in the Netherlands on reproductive technologies and embryo research have paid particular attention to the issue of health risks to women. This article focuses on the question to what extent the discourse of gender has contributed to shaping the

  7. Astronomy Education: Becoming a Hybrid Researcher

    Directory of Open Access Journals (Sweden)

    Erik Brogt

    2007-01-01

    Full Text Available This article describes the experiences of a former astronomer who is making the transition to astronomy education research as an international graduate student in the United States. The article describes the author’s encounters with education research, its methodologies, and his changing research interests as he progresses through the graduate program. It also describes his experiences with the busy life of a graduate student in American academia and his experiences as an international student.

  8. Study on Germination of Somatic Embryos of Liriodendrom Hybrids%杂交鹅掌楸体细胞胚萌发培养的研究

    Institute of Scientific and Technical Information of China (English)

    程强强; 戴小英; 宋晓琛; 江香梅; 肖复明

    2014-01-01

    The influences of development period of somatic embryos, major element and vitamin C, genotypes, different combinations with plant growth regulators and transplant medium on germination and transplanting survival for somatic embryos of Liriodendrom hybrids were studied. The results showed that the optimal developement phase of germination was torpedo-shaped embryos, and the base cultural medium of 3/4 MS and with the vitamin C used of keeping normal form from somatic embryos. The somatic embryo germination among different genotypes at the same cultural condition was different significantly, for example, the genotype 1×5002 was the highest, up to 82.46%, the genotype 1×4088 just was to 13.24%. The medium KT 0.1 mg/L+IBA 0.1mg/L can help to promote the germination of somatic embryogenesis. There were differences of seedling transplanting survival rate between the yellow subsoil and mixed peat soil, and the former was more suitable for transplanting than the later.%以杂交鹅掌楸体细胞胚为材料,研究体胚不同发育阶段、大量元素和维生素C、基因型、激素组合以及移栽基质对体胚苗萌发和移栽存活的影响。结果表明:鱼雷型胚萌发效果最好;3/4 MS培养基较适合体胚苗的萌发;Vc有利用保持体胚苗维持正常形态。不同基因型体胚苗萌发差异较大,基因型1×5002萌发效果最好,成苗率为84.26%;而1×4088仅有13.24%。 KT 0.1 mg/L+IBA 0.1 mg/L有利于促进体细胞胚的萌发。不同基因型体胚苗移栽存活率有差异,黄心土较混合泥炭土更适合体胚苗移栽。

  9. Retracing liberalism and remaking nature: designer children, research embryos, and featherless chickens.

    Science.gov (United States)

    Fox, Dov

    2010-05-01

    Liberal theory seeks to achieve toleration, civil peace, and mutual respect in pluralistic societies by making public policy without reference to arguments arising from within formative ideals about what gives value to human life. Does it make sense to set aside such conceptions of the good when it comes to controversies about stem cell research and the genetic engineering of people or animals? Whether it is reasonable to bracket our world-views in such cases depends on how we answer the moral questions that the use of these biotechnologies presuppose. I argue that the moral language of liberal justice - of rights and duties, interests and opportunities, freedom and consent, equality and fairness - cannot speak to these underlying concerns about what the human embryo is, why the natural lottery matters to us, and whether 'animal nature' is worth preserving. I conclude that liberal theory is incapable of furnishing a coherent or desirable account to govern the way we use our emerging powers of biotechnology.

  10. Rationality and religion in the public debate on embryo stem cell research and prenatal diagnostics.

    Science.gov (United States)

    Myskja, Bjørn K

    2009-06-01

    Jürgen Habermas has argued that religious views form a legitimate background for contributions to an open public debate, and that religion plays a particular role in formulating moral intuitions. Translating religious arguments into "generally accessible language" (Habermas, Eur J Philos 14(1):1-25, 2006) to enable them to play a role in political decisions is a common task for religious and non-religious citizens. The article discusses Habermas' view, questioning the particular role of religion, but accepting the significance of including such counter-voices to the predominant views. Furthermore it is pointed out that not only religious but also numerous secular views stand in need of translation to be able to bear on policy matters. Accepting Habermas' general framework, I raise the question whether experts (such as clinicians working in relevant specialised areas of care) participating in political debates on biomedical issues have a duty to state their religious worldview, and to what extent the American government decision to restrict embryo stem cell research is an illegitimate transgression of the State-Church divide.

  11. 阿月浑子杂种幼胚培养技术的研究%Study on hybrid immature embryo culture technology of Pistacia vera L.

    Institute of Scientific and Technical Information of China (English)

    庞曼; 王洁; 董倩; 李旭新; 白志英; 路丙社

    2012-01-01

    以阿月浑子杂种果实和人工授粉后120 d的杂种幼胚为试材,对杂种果实生长发育规律及幼胚培养进行了研究,探讨了冷藏处理时间、不同光照条件和培养时间对幼胚萌发和成苗的影响.结果表明:阿月浑子人工授粉80 d后,单果鲜重和PF值仅为1.27 g和0.24;授粉后100 d,单果鲜重和PF值为1.57g和0.43;授粉后120 d,单果鲜重和PF值为2.81 g和0.80;3种冷藏处理中,以冷藏处理90 d时幼胚萌发及生长效果最好,幼胚萌率为91.67%,平均真叶数为6.09个,平均苗高为4.14 cm;在培养方式上,以黑暗处理后培养20 d效果最好,幼胚萌发率为86.67%,平均真叶数为5.38,平均苗高为4.23 cm.%In this experiment, hybrid fruits and immature embryos of Pistacia vera L.growing for 120 d after artificial pollination, were used as materials,The growth rule and immature embryo culture of pistachio's hybrid fruit were studied. The effects of cold treatment time, different light conditions and culture time on immature embryo development and normal seedling rate were also investigated, indicating that the single-fruit fresh weight and PF value were only 1. 27 g and 0. 24 when growing for 80 d after artificial pollination, reaching 1.57 g and 0. 43 in 100 d after, with the average fruit fresh weight and PF value being 2.81 g and 0. 80 respectively, in 120 d after. The suitable cold treatment time for immature embryo germination and growth is 90 d.the rate of embryo germination is 91. 67%, the average leaf number is 6. 09 and the average seedling height is 4. 14 cm. It was suggested that the best culture way is the dark treatment for 20 d, the rate of embryo germination is 86. 67%, the average leaf number is 5. 38 and the average seedling height is 4. 23 cm.

  12. Embryo splitting

    Directory of Open Access Journals (Sweden)

    Karl Illmensee

    2010-04-01

    Full Text Available Mammalian embryo splitting has successfully been established in farm animals. Embryo splitting is safely and efficiently used for assisted reproduction in several livestock species. In the mouse, efficient embryo splitting as well as single blastomere cloning have been developed in this animal system. In nonhuman primates embryo splitting has resulted in several pregnancies. Human embryo splitting has been reported recently. Microsurgical embryo splitting under Institutional Review Board approval has been carried out to determine its efficiency for blastocyst development. Embryo splitting at the 6–8 cell stage provided a much higher developmental efficiency compared to splitting at the 2–5 cell stage. Embryo splitting may be advantageous for providing additional embryos to be cryopreserved and for patients with low response to hormonal stimulation in assisted reproduction programs. Social and ethical issues concerning embryo splitting are included regarding ethics committee guidelines. Prognostic perspectives are presented for human embryo splitting in reproductive medicine.

  13. Subtractive and differential hybridization molecular analyses of Ceratitis capitata XX/XY versus XX embryos to search for male-specific early transcribed genes.

    Science.gov (United States)

    Salvemini, Marco; D'Amato, Rocco; Petrella, Valeria; Ippolito, Domenica; Ventre, Giuseppe; Zhang, Ying; Saccone, Giuseppe

    2014-01-01

    The agricultural pest Ceratitis capitata, also known as the Mediterranean fruit fly or Medfly, is a fruit crop pest of very high economic relevance in different continents. The strategy to separate Ceratitis males from females (sexing) in mass rearing facilities is a useful step before the sterilization and release of male-only flies in Sterile Insect Technique control programs (SIT). The identification of genes having early embryonic male-specific expression, including Y-linked genes, such as the Maleness factor, could help to design novel and improved methods of sexing in combination with transgenesis, aiming to confer conditional female-specific lethality or female-to-male sexual reversal. We used a combination of Suppression Subtractive Hybrydization (SSH), Mirror Orientation Selection (MOS) anddifferential screening hybridization (DSH) techniques to approach the problem of isolating corresponding mRNAs expressed in XX/XY embryos versus XX-only embryos during a narrow developmental window (8-10 hours after egg laying, AEL ). Here we describe a novel strategy we have conceived to obtain relatively large amounts of XX-only embryos staged at 8-10 h AEL and so to extract few micrograms of polyA+ required to apply the complex technical procedure. The combination of these 3 techniques led to the identification of a Y-linked putative gene, CcGm2, sharing high sequence identity to a paralogous gene, CcGm1, localized either on an autosome or on the X chromosome. We propose that CcGm2 is a first interesting putative Y-linked gene which could play a role in sex determination. The function exterted by this gene should be investigated by novel genetic tools, such as CRISPR-CAS9, which will permit to target only the Y-linked paralogue, avoiding to interfere with the autosomal or X-linked paralogue function.

  14. Endogenous expression of ASLV viral proteins in specific pathogen free chicken embryos: relevance for the developmental biology research field

    Directory of Open Access Journals (Sweden)

    Canto-Soler M Valeria

    2010-10-01

    Full Text Available Abstract Background The use of Specific Pathogen Free (SPF eggs in combination with RCAS retrovirus, a member of the Avian Sarcoma-Leukosis Virus (ASLV family, is of standard practice to study gene function and development. SPF eggs are certified free of infection by specific pathogen viruses of either exogenous or endogenous origin, including those belonging to the ASLV family. Based on this, SPF embryos are considered to be free of ASLV viral protein expression, and consequently in developmental research studies RCAS infected cells are routinely identified by immunohistochemistry against the ASLV viral proteins p19 and p27. Contrary to this generally accepted notion, observations in our laboratory suggested that certified SPF chicken embryos may endogenously express ASLV viral proteins p19 and p27. Since these observations may have significant implications for the developmental research field we further investigated this possibility. Results We demonstrate that certified SPF chicken embryos have transcriptionally active endogenous ASLV loci (ev loci capable of expressing ASLV viral proteins, such as p19 and p27, even when those loci are not capable of producing viral particles. We also show that the extent of viral protein expression in embryonic tissues varies not only among flocks but also between embryos of the same flock. In addition, our genetic screening revealed significant heterogeneity in ev loci composition even among embryos of the same flock. Conclusions These observations have critical implications for the developmental biology research field, since they strongly suggest that the current standard methodology used in experimental studies using the chick embryo and RCAS vectors may lead to inaccurate interpretation of results. Retrospectively, our observations suggest that studies in which infected cells have been identified simply by pan-ASLV viral protein expression may need to be considered with caution. For future studies, they

  15. Use of a hybrid computer in engineering-seismology research

    Science.gov (United States)

    Park, R.B.; Hays, W.W.

    1977-01-01

    A hybrid computer is an important tool in the seismological research conducted by the U.S. Geological Survey in support of the Energy Research and Development Administration nuclear explosion testing program at the Nevada Test Site and the U.S. Geological Survey Earthquake Hazard Reduction Program. The hybrid computer system, which employs both digital and analog computational techniques, facilitates efficient seismic data processing. Standard data processing operations include: (1) preview of dubbed magnetic tapes of data; (2) correction of data for instrument response; (3) derivation of displacement and acceleration time histories from velocity recordings; (4) extraction of peak-amplitude data; (5) digitization of time histories; (6) rotation of instrumental axes; (7) derivation of response spectra; and (8) derivation of relative transfer functions between recording sites. Catalog of time histories and response spectra of ground motion from nuclear explosions and earthquakes that have been processed by the hybrid computer are used in the Earthquake Hazard Research Program to evaluate the effects of source, propagation path, and site effects on recorded ground motion; to assess seismic risk; to predict system response; and to solve system design problems.

  16. Detection of isoform-specific fibroblast growth factor receptors by whole-mount in situ hybridization in early chick embryos.

    Science.gov (United States)

    Nishita, Junko; Ohta, Sho; Bleyl, Steven B; Schoenwolf, Gary C

    2011-06-01

    We have developed "b" and "c" isoform-specific chicken fibroblast growth factor (FGF) receptor 1-3 probes for in situ hybridization. We rigorously demonstrate the specificity of these probes by using both dot blot hybridization and whole-mount in situ hybridization during neurulation and early postneurulation stages, and we compare expression patterns of each of the three isoform-specific probes to one another and to generic probes to each of the three (non-isoform-specific) FGF receptors. We show that the expression pattern of each receptor is represented by the collective expression of each of its two isoforms, with the expression of each FGF receptor being most similar to that of its "c" isoform at two of the three stages studied, and that tissue and stage differences exist in the patterns of expression of the six isoforms. We demonstrate the usefulness of these probes for defining the differential tissue expression of FGF receptor 1-3 isoforms.

  17. The fish embryo toxicity test as an animal alternative method in hazard and risk assessment and scientific research

    Energy Technology Data Exchange (ETDEWEB)

    Embry, Michelle R., E-mail: membry@ilsi.org [ILSI Health and Environmental Sciences Institute, 1156 15th Street, NW, Suite 200, Washington, DC 20005 (United States); Belanger, Scott E., E-mail: belanger.se@pg.com [Procter and Gamble, Central Product Safety, PO Box 538707, Miami Valley Innovation Center, Cincinnati, OH 45253-8707 (United States); Braunbeck, Thomas A., E-mail: braunbeck@zoo.uni-heidelberg.de [University of Heidelberg, Im Neuenheimer Feld 230, Heidelberg D -69120 (Germany); Galay-Burgos, Malyka, E-mail: malyka.galay-burgos@ecetoc.org [European Centre for Ecotoxicology and Toxicology of Chemicals (ECETOC), 4 Avenue E. Van Nieuwenhuyse B-1160, Brussels (Belgium); Halder, Marlies, E-mail: marlies.halder@jrc.ec.europa.eu [European Commission, Joint Research Centre, Institute for Health and Consumer Protection, In-Vitro Methods Unit TP-580 Ispra 21027 (Italy); Hinton, David E., E-mail: dhinton@duke.edu [Duke University, Nicholas School of the Environment, PO Box 90328, Durham, NC 27708, Unites States (United States); Leonard, Marc A., E-mail: mleonard@rd.loreal.com [L' Oreal Recherche Avancee, Unite d' Ecotoxicologie, 1 av. E. Schueller, 93601 Aulnay sous bois (France); Lillicrap, Adam, E-mail: Adam.lillicrap@niva.no [AstraZeneca, Freshwater Quarry, Brixham TQ5 8BA (United Kingdom); Norberg-King, Teresa, E-mail: norberg-king.teresa@epa.gov [U.S. EPA, Mid-Continent Ecology Division, 6201 Congdon Boulevard, Duluth, MN 55804-1636 (United States); Whale, Graham, E-mail: graham.whale@shell.com [Shell Global Solutions, Analytical Technology, P.O. Box 1, Chester CH1 3SH (United Kingdom)

    2010-04-15

    Animal alternatives research has historically focused on human safety assessments and has only recently been extended to environmental testing. This is particularly for those assays that involve the use of fish. A number of alternatives are being pursued by the scientific community including the fish embryo toxicity (FET) test, a proposed replacement alternative to the acute fish test. Discussion of the FET methodology and its application in environmental assessments on a global level was needed. With this emerging issue in mind, the ILSI Health and Environmental Sciences Institute (HESI) and the European Centre for Ecotoxicology and Toxicology of Chemicals (ECETOC) held an International Workshop on the Application of the Fish Embryo Test as an Animal Alternative Method in Hazard and Risk Assessment and Scientific Research in March, 2008. The workshop included approximately 40 scientists and regulators representing government, industry, academia, and non-governmental organizations from North America, Europe, and Asia. The goal was to review the state of the science regarding the investigation of fish embryonic tests, pain and distress in fish, emerging approaches utilizing fish embryos, and the use of fish embryo toxicity test data in various types of environmental assessments (e.g., hazard, risk, effluent, and classification and labeling of chemicals). Some specific key outcomes included agreement that risk assessors need fish data for decision-making, that extending the FET to include eluethereombryos was desirable, that relevant endpoints are being used, and that additional endpoints could facilitate additional uses beyond acute toxicity testing. The FET was, however, not yet considered validated sensu OECD. An important action step will be to provide guidance on how all fish tests can be used to assess chemical hazard and to harmonize the diverse terminology used in test guidelines adopted over the past decades. Use of the FET in context of effluent assessments

  18. The fish embryo toxicity test as an animal alternative method in hazard and risk assessment and scientific research.

    Science.gov (United States)

    Embry, Michelle R; Belanger, Scott E; Braunbeck, Thomas A; Galay-Burgos, Malyka; Halder, Marlies; Hinton, David E; Léonard, Marc A; Lillicrap, Adam; Norberg-King, Teresa; Whale, Graham

    2010-04-15

    Animal alternatives research has historically focused on human safety assessments and has only recently been extended to environmental testing. This is particularly for those assays that involve the use of fish. A number of alternatives are being pursued by the scientific community including the fish embryo toxicity (FET) test, a proposed replacement alternative to the acute fish test. Discussion of the FET methodology and its application in environmental assessments on a global level was needed. With this emerging issue in mind, the ILSI Health and Environmental Sciences Institute (HESI) and the European Centre for Ecotoxicology and Toxicology of Chemicals (ECETOC) held an International Workshop on the Application of the Fish Embryo Test as an Animal Alternative Method in Hazard and Risk Assessment and Scientific Research in March, 2008. The workshop included approximately 40 scientists and regulators representing government, industry, academia, and non-governmental organizations from North America, Europe, and Asia. The goal was to review the state of the science regarding the investigation of fish embryonic tests, pain and distress in fish, emerging approaches utilizing fish embryos, and the use of fish embryo toxicity test data in various types of environmental assessments (e.g., hazard, risk, effluent, and classification and labeling of chemicals). Some specific key outcomes included agreement that risk assessors need fish data for decision-making, that extending the FET to include eluethereombryos was desirable, that relevant endpoints are being used, and that additional endpoints could facilitate additional uses beyond acute toxicity testing. The FET was, however, not yet considered validated sensu OECD. An important action step will be to provide guidance on how all fish tests can be used to assess chemical hazard and to harmonize the diverse terminology used in test guidelines adopted over the past decades. Use of the FET in context of effluent assessments

  19. Lessons from Embryos: Haeckel's Embryo Drawings, Evolution, and Secondary Biology Textbooks

    Science.gov (United States)

    Wellner, Karen L.

    2014-01-01

    In 1997, developmental biologist Michael Richardson compared his research team's embryo photographs to Ernst Haeckel's 1874 embryo drawings and called Haeckel's work "noncredible". "Science" soon published "Haeckel's Embryos: Fraud Rediscovered," and Richardson's comments further reinvigorated criticism of Haeckel by…

  20. Lessons from Embryos: Haeckel's Embryo Drawings, Evolution, and Secondary Biology Textbooks

    Science.gov (United States)

    Wellner, Karen L.

    2014-01-01

    In 1997, developmental biologist Michael Richardson compared his research team's embryo photographs to Ernst Haeckel's 1874 embryo drawings and called Haeckel's work "noncredible". "Science" soon published "Haeckel's Embryos: Fraud Rediscovered," and Richardson's comments further reinvigorated criticism of Haeckel by…

  1. Comment on a proposed draft protocol for the European Convention on Biomedicine relating to research on the human embryo and fetus.

    Science.gov (United States)

    Lebech, M M

    1998-10-01

    Judge Christian Byk renders service to the Steering Committee on Bioethics of the Council of Europe (CDBI) by proposing a draft of the protocol destined to fill in a gap in international law on the status of the human embryo. This proposal, printed in a previous issue of the Journal of Medical Ethics deserves nevertheless to be questioned on important points. Is Christian Byk proposing to legalise research on human embryos not only in vitro but also in utero?

  2. Comparison of tetraploid blastocyst microinjection of outbred Crl:CD1(ICR), hybrid B6D2F1/Tac, and inbred C57BL/6NTac embryos for generation of mice derived from embryonic stem cells.

    Science.gov (United States)

    Kirchain, Sharron M; Hayward, Alison M; Mkandawire, John M; Qi, Peimin; Burds, Aurora A

    2008-04-01

    Embryo electrofusion and tetraploid blastocyst microinjection is a modification of the traditional embryonic stem cell (ES cell)-based method to generate targeted mutant mice. Viability of tetraploid embryos is reportedly lower than with diploid embryos, with considerable interstrain variation. Here we assessed fetus and pup viability after ES cell microinjection of tetraploid blastocysts derived from outbred, hybrid, and inbred mice. Two-cell mouse embryos (C57BL/6NTac [B6], n = 788; B6D2F1/Tac [BDF1], n = 1871; Crl:CD1(ICR) [CD1], n = 1308) were electrofused; most resultant tetraploid blastocysts were injected with ES cells and surgically transferred into pseudopregnant recipient mice. Reproductive tracts were examined at midgestation for embryologic studies using B6 and BDF1 blastocysts; implantation sites and viable fetuses were counted. Pregnancies were carried to term for studies of targeted mutant mice using BDF1 and CD1 blastocysts, and pup yield was evaluated. Electrofusion rates of 2-cell embryos did not differ among B6, BDF1, and CD1 mice (overall mean, 92.8% +/- 5.4%). For embryologic studies, 244 B6 blastocysts were surgically transferred and 1 fetus was viable (0.41%), compared with 644 BDF1 blastocysts surgically transferred and 88 viable fetuses (13.7%). For targeted mutant mouse studies, 259 BDF1 blastocysts were surgically transferred yielding 10 pups (3.9%); 569 CD1 blastocysts yielded 44 pups (7.7%).

  3. ‘奥迪亚’葡萄杂交后代胚挽救及无核性状分子鉴定%Embryo rescue and seedlessness molecular identification of hybrid off- springs of ‘Otilia' grape

    Institute of Scientific and Technical Information of China (English)

    程和禾; 吴雅琴; 吴永杰; 李玉生; 陈龙; 周锡明; 赵艳华

    2012-01-01

    【目的】为了研究影响杂交后代胚挽救萌发率的主要因素,并对其无核性状进行早期鉴定,【方法】以无核、抗病葡萄品种‘奥迪亚’为母本,‘玫瑰香’、‘摩尔多瓦’和‘红地球’3个主栽品种为父本进行杂交,通过L9(3^3)正交试验,建立简单高效的胚挽救体系,并用分子标记对杂交苗无核性状进行鉴定。【结果】结果表明,影响胚挽救萌发率的最关键因素为接种时期,其次为培养基种类和NAA浓度;以‘奥迪亚’为母本的杂交胚其适宜接种程序为授粉后49~56d剥取胚珠,接种在B5或NN69培养基上充分发育70d,再转入1/2B5培养基上萌芽,‘奥迪亚’ב摩尔多瓦’杂交胚通过此程序萌发率达到了50.48%;经分子标记鉴定,各组合后代的无核株系均超过50%。【结论】利用胚挽救方法以‘奥迪亚’为杂交母本可高效创新葡萄无核种质。%[Objective]What was the main factor which influenced the embryo germination rate and whether the hybrid off-springs were seedless or not were studied in this test. [Method ]Three hybrid combi- nations were set up which were ‘Otilia' בMuscat Hamburg', ‘ Otilia' בMoldova' and ‘Otilia' × ‘Red Globe', and the female parent ‘Otilia' was seedless and disease-resistant. L9 (33) orthogonal test were designed to establish simple and efficient embryo rescue progress, and using molecular marker to identify whether the hybrid off-springs were seedless or not. [Result] The results were as follows: the most important factor that influenced the embryo germination rate was inoculation period, which is followed by the medium type and NAA concentration; the suitable embryo rescue progress for hybrid embryos, whose female parents was Otilia, was that the embryos were first inoculated at 49-56 DAF (days after fertiliza- tion), and after developed on the B5 or NN69 medium for 70 d

  4. Research on Modulation Strategies Based on Multilevel Inverter Universal Hybrid Topology

    Institute of Scientific and Technical Information of China (English)

    Zhou Jinghua; Su Yanmin; Shen Chuanwen; Zhang Lin

    2005-01-01

    Based on multi-module-cascaded inverter topology, this study presented a universal multilevel inverter hybrid topology and unified the researches on multilevel inverter topology. According to the freedom of this universal topology, several new hybrid topologies were constructed. Also, based on conventional modulation strategies- multi-carrier SPWM (Sinusoidal Pulse Width Modulation), hybrid modulation strategies were introduced corresponding to hybrid topologies, and a multilevel SVPWM (Space Vector Pulse Width Modulation) technique based on phase-shifted theory was naturally produced. Simulation and experiment results prove that hybrid topologies and corresponding modulation strategies are valid, which lay a foundation for practical application of hybrid multilevel inverter topologies.

  5. The impact of commercialisation on public perceptions of stem cell research: exploring differences across the use of induced pluripotent cells, human and animal embryos.

    Science.gov (United States)

    Critchley, Christine R; Bruce, Gordana; Farrugia, Matthew

    2013-10-01

    The development of pluripotent cells that enable stem cell research (SCR) without destroying human embryos is now a leading priority for science. Public and political controversies associated with human embryonic SCR experienced in the recent past should be alleviated if scientists no longer need to harvest cells from human embryos. This research suggests however additional issues needing attention in order to gain the public's trust and support: the use of mouse embryos and the commercialisation of research. Using a representative sample of 2,800 Australians, and an experimental telephone survey design, this research compared levels and predictors of public support for stem cell research across three cell source conditions: human embryo (HE), mouse embryo (ME) and induced pluripotent cells (iPSCs). The results revealed that the public were significantly more likely to support research using iPSCs than HE and ME cells and public compared to private research (regardless of the cell source). There was no significant difference in support for HE compared to ME research, but the former was viewed as more likely to lead to accessible health care benefits and to be associated with more trustworthy scientists. The results of a multimediation structural equation model showed that the primary reason support for SCR significantly dropped in a private compared to public context (i.e., the commercialisation effect) was because public scientists were trusted more than private scientists. This effect was consistent across all three SCR materials, suggesting that the use of mouse embryos or even iPSCs will not reduce the publics' concern with commercialised science. The implications these results have for public acceptance of stem cell and animal research are discussed in relation to possible solutions such as increasing public awareness of the regulation of animal research and benefit sharing.

  6. Ethical consideration of experimentation using living human embryos: the Catholic Church's position on human embryonic stem cell research and human cloning.

    Science.gov (United States)

    Ohara, N

    2003-01-01

    Although the potential applications of human embryonic stem cells and therapeutic cloning hold promise for the alleged medical benefits, these technologies have posed profound ethical issues because they necessitate the destruction of human embryos. A fundamental point in the issues is the concept of the moral status of human embryos. The Catholic Church has held that human life begins at the moment of conception and therefore, has defended the dignity, inviolable right to life and integrity of human embryos. The Catholic Church has opposed human embryonic stem cell research and any kind of human cloning because they are contrary to the dignity of procreation, of conjugal union and of human embryos. Moreover, these techniques have the risk of creating a sub-category of human beings that are destined basically for the convenience of others. In conclusion, science and technology can never be independent of the criterion of morality, since technology exists for man and must respect his finality.

  7. The Evolution of Legislation in the Field of Medically Assisted Reproduction and Embryo Stem Cell Research in European Union Members

    Directory of Open Access Journals (Sweden)

    Francesco Paolo Busardò

    2014-01-01

    Full Text Available Medically Assisted Reproduction (MAR, involving in vitro fertilisation (IVF, and research on embryos have created expectation to many people affected by infertility; at the same time it has generated a surplus of laws and ethical and social debates. Undoubtedly, MAR represents a rather new medical field and constant developments in medicine and new opportunities continue to defy the attempt to respond to those questions. In this paper, the authors reviewed the current legislation in the 28 EU member states trying to evaluate the different legislation paths adopted over the last 15 years and highlighting those EU countries with no specific legislation in place and MAR is covered by a general health Law and those countries in which there are no laws in this field but only “guidelines.” The second aim of this work has been to compare MAR legislation and embryo research in EU countries, which derive from different origins ranging from an extremely prohibitive approach versus a liberal one, going through a cautious regulatory approach.

  8. Non-surgical embryo transfer in pigs

    NARCIS (Netherlands)

    Hazeleger, W.

    1999-01-01

    Embryo transfer in pigs has been performed surgically for a long time. However, a less invasive, non-surgical, procedure of embryo transfer could be a valuable tool for research (to study embryo survival and embryo-uterus interactions) and practical applications (export, prevention of

  9. Cytogenetic characterization and fluorescence in situ hybridization of (GATA)10 repeats on established primary cell cultures from Indian water snake (Natrix piscator) and Indian mugger (Crocodylus palustris) embryos.

    Science.gov (United States)

    Rao, L; Turlapati, R; Patel, M; Panda, B; Tosh, D; Mangalipalli, S; Tiwari, A; Orunganti, V P; Rose, D; Anand, A; Kulashekaran, M K; Priya, S R; Mishra, R K; Majumdar, K; Aggarwal, R K; Singh, L

    2009-01-01

    Sex determination among reptiles has continued to draw the attention of geneticists and the mechanisms involved have been extensively studied and documented in the past 3 decades. The setting up of primary cell lines of reptilian tissues is an important tool in the present study which is a unique aspect not applied in earlier studies. Establishing the cell lines from various species of reptiles would help in our understanding of the mechanisms of evolution and differentiation of sex chromosomes. Therefore, in the present study, we have established for the first time primary cell cultures from Indian water snake (Natrix piscator) and Indian mugger (Crocodylus palustris) embryos. In the preliminary growth stage, 2 types of cells, fibroblast- and epithelial-like, were found to be attached and proliferating in vitro. These fibroblast-like cell cultures were later overtaken by epithelial cells. The cell lines were grown in minimal essential medium supplemented with fetal bovine serum and subcultured for a period of 8-10 months. The morphology of cell types was kept under constant observation microscopically. Interestingly, at a subsequent passage of the cells sporadically scattered neuronal-like and beating cells were observed. The suitable temperature for growth of these cell cultures was 28-30 degrees C. Chromosome analysis was performed from the actively proliferating cells, which revealed 5 pairs of macrochromosomes and 15 pairs of microchromosomes in Natrix piscator, and 15 pairs of only macrochromosomes in Crocodylus palustris. (GATA)(n) repeats are well known to be associated with sex chromosomes. Fluorescence in situ hybridization performed with (GATA)(10) repeats delineated the W chromosome in the cells of Natrix piscator which has so far not been reported. This cell culture method has presently only been applied to water snakes and crocodile embryos in the current study, but it will be employed in other reptilian species and could go a long way to being a

  10. Building a Hybrid Experimental Platform for Mobile Botnet Research

    Directory of Open Access Journals (Sweden)

    Apostolos Malatras

    2016-03-01

    Full Text Available Mobile botnets are an emerging security threat that aims at exploiting the wide penetration of mobile devices and systems and their vulnerabilities in the same spirit of traditional botnets. Mobile botmasters take advantage of infected mobile devices and issue command and control operations on them to extract personal information, cause denial of service or gain financially. To date, research on countering such attacks or studying their effects has been conducted in a sporadic manner that hinders the repetition of experiments and thus limits their validity. We present here our work on a hybrid experimental platform for mobile botnets that supports the execution and monitoring of related scenarios concerning their infection, attack vectors, propagation, etc. The platform is based on principles of flexibility, extensibility and facilitates the setup of scalable experiments utilising both real and emulated mobile systems. We also discuss a novel method of estimating the active bot population in a botnet and illustrate its deployment on the experimental platform.

  11. Viability of bovine demi embryo after splitting of fresh and frozen thawed embryo derived from in vitro embryo production

    Directory of Open Access Journals (Sweden)

    M Imron

    2007-06-01

    Full Text Available In vivo embryo production was limited by number of donor, wide variability respond due to superovulation program and also immunoactifity of superovulation hormone (FSH. Splitting technology could be an alternative to increase the number of transferrable embryos into recipien cows. Splitting is done with cutting embryo becoming two equal pieces (called demi embrio base on ICM orientation. The objective of this research was to determine the viability of demi embryo obtained from embryo splitting of fresh and frozen thawed embryo. The results showed that demi embryos which performed blastocoel reexpansion 3 hours after embryo splitting using fresh and frozen thawed embryos were 76.9 and 76.2% respectively. Base on existention of inner cell mass (ICM, the number of demi embryos developed with ICM from fresh and frozen thawed embryos were not significantly different (90.6 and 85.7% respectively. The cell number of demi embryo from fresh embryos splitting was not different compared with those from frozen thawed embryos (36.1 and 35.9 respectively. These finding indicated that embryo splitting can be applied to frozen thawed embryos with certain condition as well as fresh embryos.

  12. Experimental cloning of embryos through human-rabbit inter-species nuclear transfer

    Institute of Scientific and Technical Information of China (English)

    JI Jingjuan; GUO Tonghang; TONG Xianhong; LUO Lihua; ZHOU Guixiang; FU Yingyun; LIU Yusheng

    2007-01-01

    Therapeutic cloning,which is based on human somatic cell nuclear transfer,is one of our major research objectives.Though inter-species nuclear transfer has been introduced to construct human somatic cell cloned embryos,the effects of type,passage,and preparation method of donor cells on embryo development remain unclear.In our experiment,cloned embryos were reconstructed with different passage and preparation methods of ossocartilaginous cell,skin fibroblast,and cumulus cells.The cumulus cell embryos showed significantly higher development rates than the other two (P<0.05).The development rate of embryos reconstructed with skin fibroblasts of different passage number and somatic cells of different chilling durations showed no significant difference.Also,fluorescence in situ hybridization (FISH)was conducted to detect nuclear derivation of the embryos.The result showed that the nuclei of the inter-species cloned embryo cells came from human.We conclude that (1)cloned embryos can be constructed through human-rabbit interspecies nuclear transfer;(2)different kinds of somatic cells result in different efficiency of nuclear transfer,while in vitro passage of the donor does not influence embryo development;(3)refrigeration is a convenient and efficient donor cell preparation method.Finally,it is feasible to detect DNA gcnotype through FISH.

  13. Whole mount in situ hybridization of E8.5 to E12.5 rat embryos%E8.5-E12.5大鼠胚胎整体原位杂交技术

    Institute of Scientific and Technical Information of China (English)

    张吉霞; 蔡玉瑾; 谢耀丽; 李海荣; 乔从进; 崔慧林

    2013-01-01

    目的:通过优化实验条件,建立大鼠胚胎整体原位杂交方法.方法:E8.5-E10.5大鼠胚胎4%多聚甲醛固定6h,不经蛋白酶K消化;E11.5-E12.5胚胎4%多聚甲醛固定过夜,蛋白酶K系列稀释实验确定消化浓度和时间.E8.5-E12.5胚胎预杂交2h,地高辛标记的甘油二酯激酶ζ(DGKζ)寡核苷酸探针杂交24h,山羊血清封闭2.5~3h,地高辛抗体4℃过夜,冷TBST和NTMT漂洗1~2h,NBT/BCIP避光显色.应用免疫组织化学方法观察DGKζ在E12.5大鼠胚胎组织的表达.结果:DGKζ在不同胚龄大鼠胚胎均有清晰的杂交信号,主要集中在神经系统;E12.5大鼠胚胎脑泡、背根神经节有较强表达,与免疫组化结果一致.结论:本研究建立了简便、可行、重复性高的E8.5-E12.5大鼠胚胎整体原位杂交方法.%Objective:To establish a method for whole mount in situ hybridization of rat embryos by optimizing experimental conditions.Methods:E8.5-E10.5 rat embryos were fixed in 4% paraformaldehyde for 6 hours,and had no proteinase K digestion.E11.5-E12.5 rat embryos were fixed in 4% paraformaldehyde overnight.The concentration and time of proteinase K digestion were analyzed by serial dilution.E8.5-E12.5 embryos were pre-hybridized for 2 hours and hybridized with digoxigenin-labeled diacylglycerol kinase ζ (DGKζ) oligonucleotide probe for 24 hours,blocked by goat serum for 2.5-3 hours,and incubated anti-digoxigenin antibody overnight at 4℃.Then the embryos were rinsed in cool TBST and NTMT for 1-2 hours and developed with NBT/BCIP in dark.The expression of DGKζ protein in E12.5 embryos was observed by using immunohistochemistry.Results:DGKζ positive signals mainly located in nervous system of rat embryos at different ages and were viewed obviously.DGKζ positive signals were observed strongly in cephalic vesicles,dorsal root ganglions of E12.5 rat embryos,which was consistent with the immunohistochemical results.Conclusion:The present study has established

  14. Research on the Interior Sound Quality in Hybrid Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Liao Lian Ying

    2016-01-01

    Full Text Available Even the overall level of vehicle interior noise of hybrid electric vehicle (HEV reduced to a certain degree, the vibration and noise generated by the engine, motor, generator and power split have made greater effect on the vehicle interior sound quality in HEV. In order to research the feature of vehicle interior sound quality in HEV, the HEV is used to be the research object, the binaural noise sample of the driver when playing different kinds of music in the vehicle with the speed of sixty kilometers per hour is collected. ArtemiS is used to conduct frequency division processing, so as to obtain the relative weight of each frequency band and the overall noise. The tone, roughness and sharpness of sound quality subjective evaluation parameters are quantified, the SPSS is used to establish the linear regression model of the sample, and the best masking music tracks are found out. Then, the sound samples that contains the best music tracks and the simple vehicle interior noise are re-collected, the regression model and ArtemiS are used to predict the subjective evaluation value. The research results show that when adding the music, the tone degree rises and the lowering degree decreases, thus the disturbing degree reduces, which significantly improves the sound quality in the HEV.

  15. Research on a New Hybrid System of a Tyre Crane Using Supercapacitors

    Institute of Scientific and Technical Information of China (English)

    XU Li; GAO Xiao-hong; HU Yi

    2008-01-01

    Research on a hybrid system of a crane is a focus which considers environmental protection and energy saving.A new environmental protection and energy saving hybrid system of tyre crane.which utilizes supercapacitors as the energy store device,is presented.Analyzing the pdneiple of supercapacitors,the model of the crane's hybrid system is set up in this paper,and the model of main blocks are established.Through simulation analyzing,the energy saving result of the new hybrid system is obtained,and the good application value of the new hybrid system is explained.

  16. Research of IDSS Architecture Based on Hybrid Systems

    Institute of Scientific and Technical Information of China (English)

    MA Biao; YANG Bao-an

    2005-01-01

    This paper discusses the necessity of building IDSS on hybrid systems, and adopts XML technology to manage isomeric knowledge in hybrid systems. The paper proposes a new architecture of hybrid systems based IDSS whose core system is isomeric knowledge system. The architecture is composed of knowledge component, problems processing system, data component and intelligent user interface. This new architecture aims to enhance the capability of integrating hybrid systems, to improve the supporting effectiveness of decision-making and the intelligent level of IDSS, and tries a new way to elevate the system's ability of handling and learning knowledge.

  17. Electric and Hybrid Vehicle System Research and Development Project: Hybrid Vehicle Potential Assessment. Volume 1. Summary

    Energy Technology Data Exchange (ETDEWEB)

    Surber, F.T.

    1979-09-30

    The results of investigations conducted under Ce Hybrid Vehicle Potential Assessment Task are reported in 10 volumes. This volume contains an overview of the study and its results. The purpose of the overall study was to determine if the petroleum fuel savings achievable through the use of hybrid electric vehicles is worth the R and D expenditures needed to develop the hybrid vehicles and to determine R and D priorities. It was concluded that by the year 2010 hybrid vehicles could replace 80% of the automotive power that would otherwise be produced from petroleum fuels; the public should not suffer any mobility loss through the use of hybrid vehicles; high initial and life-cycle costs are a limiting factor; and R and D funds should be spent for systems design and the development of low-cost batteries and controllers. (LCL)

  18. Cultivo de embriões em retrocruzamentos entre Triticum aestivum Thell. e Agropyron elongatum host. & beauv. Embryo culture of backcrosses between hybrids of Triticum aestivum Thell. and Agropyron elongatum host. & beauv.

    Directory of Open Access Journals (Sweden)

    Dilma Cristina Angra

    1999-02-01

    Full Text Available A resistência a diversas moléstias fúngicas do trigo tem sido transferida de espécies perenes da tribo Triticeae, mas o híbrido produzido pelo cruzamento intergenérico apresenta embrião abortivo. Embora a técnica de resgate e cultivo in vitro destes embriões já seja amplamente utilizada, sua eficiência ainda é muito baixa. Este trabalho objetivou a obtenção de progênies de retrocruzamentos em híbrido F1 (2n=56, proveniente do cruzamento de trigo (Triticum aestivum (2n=42 com Agropyron elongatum (2n=70, utilizando-se a técnica de cultivo in vitro dos embriões imaturos. Partindo-se do material perene na geração F1, utilizou-se o trigo como parental recorrente nos retrocruzamentos. A eficiência da polinização foi de 6% no primeiro retrocruzamento (RC1 e de 12,4% no segundo (RC2. As plantas do RC1 foram viabilizadas pelo resgate e cultivo in vitro dos embriões imaturos utilizando- se o meio batata-regeneração, com adição de vitaminas. De 22 sementes, 18 embriões foram resgatados e cultivados in vitro, originando 12 plântulas. Desses embriões, 50% foram normais, 27,8% apresentaram tamanho reduzido, 16,7% foram deformados e 5,5% apresentaram desenvolvimento retardado. A eficiência do cultivo dos embriões na regeneração de plântulas foi de 66,6%. Tal resultado indica que a técnica de resgate e o meio de cultura utilizados foram eficientes para o cultivo e regeneração dos embriões híbridos, obtendo progênies viáveis de retrocruzamentos a partir de híbridos intergenéricos, nas condições realizadas.Resistance to fungal diseases of wheat has been transferred from perennial species of tribe Triticeae, but the hybrid so formed presents immature embryos. Although rescue and in vitro culture of these embryos has been widely utilized, its efficiency is still very low. This work aimed to obtain backcrossing progenies in hybrid F1 (2n=56, derived from crossing between wheat (Triticum aestivum (2n=42 and Agropyron

  19. Current Challenges and Prospective Research for Upscaling Hybrid Perovskite Photovoltaics.

    Science.gov (United States)

    Williams, Spencer T; Rajagopal, Adharsh; Chueh, Chu-Chen; Jen, Alex K-Y

    2016-03-01

    Organic-inorganic hybrid perovskite photovoltaics (PSCs) are poised to push toward technology translation, but significant challenges complicating commercialization remain. Though J-V hysteresis and ecotoxicity are uniquely imposing issues at scale, CH3NH3PbI3 degradation is by far the sharpest limitation to the technology's potential market contribution. Herein, we offer a perspective on the practical market potential of PSCs, the nature of fundamental PSC challenges at scale, and an outline of prospective solutions for achieving module scale PSC production tailored to intrinsic advantages of CH3NH3PbI3. Although integrating PSCs into the energy grid is complicated by CH3NH3PbI3 degradation, the ability of PSCs to contribute to consumer electronics and other niche markets like those organic photovoltaics have sought footing in rests primarily upon the technology's price point. Thus, slot die, roll-to-roll processing has the greatest potential to enable PSC scale-up, and herein, we present a perspective on the research necessary to realize fully printable PSCs at scale.

  20. Zebrafish embryos and larvae as a complementary model for behavioural research

    NARCIS (Netherlands)

    Ahmad, Farooq

    2014-01-01

    The main focus of the research that makes up this thesis was to translate rodent behavioural assays to larval zebrafish for better time and resource management in biomedical research, pharmaceutical research and development. •The larval zebrafish is a useful model in toxicology and drug discovery. H

  1. Phaseolus immature embryo rescue technology.

    Science.gov (United States)

    Geerts, Pascal; Toussaint, André; Mergeai, Guy; Baudoin, Jean-Pierre

    2011-01-01

    Predominant among the production constraints of the common bean Phaseolus vulgaris are infestation of Ascochyta blight, Bean Golden Mosaic virus (BGMV), and Bean Fly. Interbreeding with Phaseolus -coccineus L. and/or Phaseolus polyanthus Greenm has been shown to provide P. vulgaris with greater resistance to these diseases. For interspecific crosses to be successful, it is important to use P. coccineus and P. polyanthus as female parents; this prevents rapid reversal to the recurrent parent P. vulgaris. Although incompatibility barriers are post-zygotic, early hybrid embryo abortion limits the success of F1 crosses. While rescue techniques for globular and early heart-shaped embryos have improved in recent years, -success in hybridization remains very low. In this study, we describe six steps that allowed us to rescue 2-day-old P. vulgaris embryos using a pod culture technique. Our methods consisted of (i) pod culture, (ii) extraction and culture of immature embryos, (iii) dehydration of embryos, (iv) germination of embryos, (v) rooting of developed shoots, and (vi) hardening of plantlets.

  2. Admixed human embryos and stem cells: legislative, ethical and scientific advances.

    Science.gov (United States)

    Bahadur, G; Iqbal, M; Malik, S; Sanyal, A; Wafa, R; Noble, R

    2008-01-01

    This paper examines the regulatory framework currently governing the creation of animal-human hybrids and chimera embryos in stem cell research, and some of the ethical implications of such research. It discusses the findings of a recent government select committee that considered the topic. It considers the debate around the precise definition of a human embryo, and whether such hybrids therefore fall within the remit of the Human Fertilisation and Embryology Authority. It outlines the advantages of such hybrids, in lessening the need for human egg donors, as well as the moral objections to species boundary violation. It calls for an examination of the scientific benefits of such research to inform debate on the question, and argues for the need to take genuine account of the public's views on this matter.

  3. RESEARCHES REGARDING THE INFLUENCE OF RECOVERY MEDIA ON THE IN VITRO DEVELOPMENT CAPACITY OF THE PREIMPLANTATIONAL MOUSE EMBRYO

    Directory of Open Access Journals (Sweden)

    ADA CEAN

    2009-05-01

    Full Text Available Phosphate Bufered Saline with 0.4% BSA and M2 medium are one of the most common media used in embryorecovery. The aim of our paper was to investigate if the recovery media used for the recovery of the mouseembryo is influencing in vitro developmental capacity. As biological material we used 10 used were mousefemales, age 2 months superovulated with 5UI PMSG (Pregnant Mare Serum Gonadotropine and 5 UI hCG(human Corionic Gonadotropine. The embryos used were recovered, by oviduct flushing, at 24 hours from theidentification of the vaginal plug. The majority of the embryos (78.3% were in two cells stage. A total of 123, 2cells embryos were cultivated in M16 medium. The evolution of the embryos was examined at 24, 48 and 72hours interval. The proportion of hatched blastocyst was higher at the embryos recovered with M2 (53.7%compared with the embryos recovered with PBS 0.4% BSA. The difference is statistically very significant(p<0.001. Embryos recovered in M2 media have a higher in vitro developmental capacity compared with theembryos recovered in PBS media supplemented with 0,4% BSA, possibly because of the sodium bicarbonate andlactate used in M2 media for pH regulation.

  4. Animal eggs for stem cell research: a path not worth taking.

    Science.gov (United States)

    Baylis, Francoise

    2008-12-01

    In January 2008, the Human Fertilisation and Embryology Authority (HFEA) (London, UK) issued two 1-year licenses for cytoplasmic hybrid embryo research. This article situates the HFEA's decision in its wider scientific and political context in which, until quite recently, the debate about human embryonic stem cell research has focused narrowly on the moral status of the developing human embryo. Next, ethical arguments against crossing species boundaries with humans are canvassed. Finally, a new argument about the risks of harm to women egg providers resulting from research involving the creation of humanesque cytoplasmic hybrid embryos is elaborated. Taken together these ethical concerns about the moral status of the human embryo, about the ethics of crossing species boundaries with humans, and about the potential harms to women (concerns that independently are more or less weighty for different constituencies), provide good reason to eschew humanesque cytoplasmic hybrid embryo research in favor of less ethically controversial means to the laudable end of successful regenerative medicine.

  5. Assisted reproduction with gametes and embryos: what research is needed and fundable?

    Science.gov (United States)

    Seidel, George E

    2016-01-01

    Principles for selecting future research projects include interests of investigators, fundability, potential applications, ethical considerations, being able to formulate testable hypotheses and choosing the best models, including selection of the most appropriate species. The following 10 areas of assisted reproduction seem especially appropriate for further research: efficacious capacitation of bovine spermatozoa in vitro; improved in vitro bovine oocyte maturation; decreasing variability and increasing efficacy of bovine superovulation; improved fertility of sexed semen; improving equine IVF; improving cryopreservation of rooster spermatozoa; understanding differences between males in success of sperm cryopreservation and reasons for success in competitive fertilisation; mechanisms of reprogramming somatic cell nuclei after nuclear transfer; regulation of differentiation of ovarian primordial follicles; and means by which spermatozoa maintain fertility during storage in the epididymis. Issues are species specific for several of these topics, in most cases because the biology is species specific.

  6. Research on the progress of juvenile in vitro embryo technology%幼羔胚胎体外生产技术研究进展

    Institute of Scientific and Technical Information of China (English)

    赵金红; 黄勇富; 任航行; 高立芳

    2012-01-01

    幼羔胚胎体外生产技术(JIVET)是全球草食类动物繁殖技术中最先进的生物工程技术。国内外对幼羔经激素诱导后生产胚胎已作了许多研究,并取得一定的成果,本文就其研究进展作一综述。%Juvenile in vitro embryo technology is the most advanced bio-engineering technology of grazing animal breeding techniques around the world. There have a lot of research about young lambs′ embryos production after hormone-induced at home and abroad, and have achieved certain success. So this paper reviewed the research progress about JIVET.

  7. Transfer of Dicamba Tolerance from Sinapis arvensis to Brassica napus via Embryo Rescue and Recurrent Backcross Breeding.

    Directory of Open Access Journals (Sweden)

    M Jugulam

    Full Text Available Auxinic herbicides (e.g. dicamba are extensively used in agriculture to selectively control broadleaf weeds. Although cultivated species of Brassicaceae (e.g. Canola are susceptible to auxinic herbicides, some biotypes of Sinapis arvensis (wild mustard were found dicamba resistant in Canada. In this research, dicamba tolerance from wild mustard was introgressed into canola through embryo rescue followed by conventional breeding. Intergeneric hybrids between S. arvensis (2n = 18 and B. napus (2n = 38 were produced through embryo rescue. Embryo formation and hybrid plant regeneration was achieved. Transfer of dicamba tolerance from S. arvensis into the hybrid plants was determined by molecular analysis and at the whole plant level. Dicamba tolerance was introgressed into B. napus by backcrossing for seven generations. Homozygous dicamba-tolerant B. napus lines were identified. The ploidy of the hybrid progeny was assessed by flow cytometry. Finally, introgression of the piece of DNA possibly containing the dicamba tolerance gene into B. napus was confirmed using florescence in situ hybridization (FISH. This research demonstrates for the first time stable introgression of dicamba tolerance from S. arvensis into B. napus via in vitro embryo rescue followed by repeated backcross breeding. Creation of dicamba-tolerant B. napus varieties by this approach may have potential to provide options to growers to choose a desirable herbicide-tolerant technology. Furthermore, adoption of such technology facilitates effective weed control, less tillage, and possibly minimize evolution of herbicide resistant weeds.

  8. Numerical Research on Hybrid Fuel Locking Device for Upward Flow Core-Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Huh, Hyung; Cho, Yeong-Garp; Yoo, Yeon-Sik; Ryu, Jeong-Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    The assembly must be held firmly against these forces, but cannot be permanently attached to the support stand because periodic refueling of the reactor requires removal or relocation of each assembly. There are so many kinds of fuel locking device, but they are operated manually. As a part of a new project, we have investigated a hybrid fuel locking device (HFLD) for research reactor which is operated automatically. Prior method of holding down the fuel assembly includes a hybrid zero electromagnet consisting of an electromagnet and a permanent magnet. The role of an electromagnet is converged to zero power for overcoming the lifting power of a permanent magnet by controlling the coil current. At this time, a HFLD is an unlocking state. On the contrary, it is locking state that only a permanent magnet works when the power of an electromagnet is off. The results of a FEM in this work lead to the following conclusions: (1) It is possible that an electromagnet is converged to zero power for overcoming the lifting power of a permanent magnet by remote controlling the coil current. (2) At this time, it is able to detect remotely using proximity sensor whether a HFLD is latched or not.

  9. Subsonic Ultra Green Aircraft Research: Phase 2. Volume 2; Hybrid Electric Design Exploration

    Science.gov (United States)

    Bradley, Marty K.; Droney, Christopher K.

    2015-01-01

    This report summarizes the hybrid electric concept design, analysis, and modeling work accomplished by the Boeing Subsonic Ultra Green Aircraft Research (SUGAR) team, consisting of Boeing Research and Technology, Boeing Commercial Airplanes, General Electric, and Georgia Tech.Performance and sizing tasks were conducted for hybrid electric versions of a conventional tube-and-wing aircraft and a hybrid wing body. The high wing Truss Braced Wing (TBW) SUGAR Volt was updated based on results from the TBW work (documented separately) and new engine performance models. Energy cost and acoustic analyses were conducted and technology roadmaps were updated for hybrid electric and battery technology. NOx emissions were calculated for landing and takeoff (LTO) and cruise. NPSS models were developed for hybrid electric components and tested using an integrated analysis of superconducting and non-superconducting hybrid electric engines. The hybrid electric SUGAR Volt was shown to produce significant emissions and fuel burn reductions beyond those achieved by the conventionally powered SUGAR High and was able to meet the NASA goals for fuel burn. Total energy utilization was not decreased but reduced energy cost can be achieved for some scenarios. The team was not able to identify a technology development path to meet NASA's noise goals

  10. Generation and developmental characteristics of porcine tetraploid embryos and tetraploid/diploid chimeric embryos.

    Science.gov (United States)

    He, Wenteng; Kong, Qingran; Shi, Yongqian; Xie, Bingteng; Jiao, Mingxia; Huang, Tianqing; Guo, Shimeng; Hu, Kui; Liu, Zhonghua

    2013-10-01

    The aim of this study was to optimize electrofusion conditions for generating porcine tetraploid (4n) embryos and produce tetraploid/diploid (4n/2n) chimeric embryos. Different electric field intensities were tested and 2 direct current (DC) pulses of 0.9 kV/cm for 30 μs was selected as the optimum condition for electrofusion of 2-cell embryos to produce 4n embryos. The fusion rate of 2-cell embryos and the development rate to blastocyst of presumably 4n embryos, reached 85.4% and 28.5%, respectively. 68.18% of the fused embryos were found to be 4n as demonstrated by fluorescent in situ hybridization (FISH). Although the number of blastomeres in 4n blastocysts was significantly lower than in 2n blastocysts (P0.05), suggesting that the blastocyst forming capacity in 4n embryos is similar to those in 2n embryos. Moreover, 4n/2n chimeric embryos were obtained by aggregation of 4n and 2n embryos. We found that the developmental rate and cell number of blastocysts of 4-cell (4n)/4-cell (2n) chimeric embryos were significantly higher than those of 2-cell (4n)/4-cell (2n), 4-cell (4n)/8-cell (2n), 4-cell (4n)/2-cell (2n) chimeric embryos (P<0.05). Consistent with mouse chimeras, the majority of 4n cells contribute to the trophectoderm (TE), while the 2n cells are mainly present in the inner cell mass (ICM) of porcine 4n/2n chimeric embryos. Our study established a feasible and efficient approach to produce porcine 4n embryos and 4n/2n chimeric embryos.

  11. Wide crossing in lentil through embryo rescue.

    Science.gov (United States)

    Fratini, Richard; Ruiz, Maria L

    2011-01-01

    Lentil seeds have provided an appreciated source of protein, carbohydrates and fibre to the diet of humans since the dawn of agriculture. Low amounts of variation have been detected in the cultivated lentil germplasm collections. Interspecific crosses allow for the introgression of important alleles of agricultural interest from wild species, such as the resistance or tolerance to abiotic and biotic stresses. Interspecific crosses within the genus Lens generally abort and embryo rescue techniques are necessary to recover hybrids. The in vitro culture procedure to rescue interspecific hybrids of Lens consists of at least four different stages: (1) in ovulo embryo culture (2), embryo culture, (3) plantlet development and finally, (4) the gradual habituation to ex vitro conditions of the recovered interspecific hybrid plantlets. In this chapter, the approach to rescue interspecific hybrids in the genus Lens is outlined.

  12. Visit and course at Hunan Hybrid Rice Research Ceater ( HHRRC )

    Institute of Scientific and Technical Information of China (English)

    TANZhijun

    1992-01-01

    Invited by Prof YUAN Longping 3 Japanese scientists of the delegation of National Federation of Agricultural Cooperative Association (ZEN-NOH) led by Hibino, came to visit HHRRC. During their visit, HHRRC experts introduced to them the advances in hybrid rice research in China and the Japanese guests reported the recent progresses on improvement of grain quality and cultivation techniques for indica/japonica hybrid rice.

  13. The research of controller area network on hybrid electrical vehicle

    Institute of Scientific and Technical Information of China (English)

    Wu Hongxing; Song Liwei; Kou Baoquan; Cheng Shukang

    2006-01-01

    It is of increasing importance to design and implement vehicle networks for transferring information between electrical control units on Hybrid Electrical Vehicle (HEV). This paper presents a scheme of using Controller Area Network (CAN) technology to realize communication and datasharing between the electrical units on the HEV. The principle and communication protocol of Electrical Control Units (ECU) CAN node are introduced. By considering different sensitivity of the devices to the latency of data transportation, a new design procedure is proposed for the purpose of simplifying network codes and wiring harness, reducing assembly space and weight, improving assembly efficiency, and enhancing fault-diagnose in auto networks.

  14. Research on stellarator-mirror fission-fusion hybrid

    Science.gov (United States)

    Moiseenko, V. E.; Kotenko, V. G.; Chernitskiy, S. V.; Nemov, V. V.; Ågren, O.; Noack, K.; Kalyuzhnyi, V. N.; Hagnestål, A.; Källne, J.; Voitsenya, V. S.; Garkusha, I. E.

    2014-09-01

    The development of a stellarator-mirror fission-fusion hybrid concept is reviewed. The hybrid comprises of a fusion neutron source and a powerful sub-critical fast fission reactor core. The aim is the transmutation of spent nuclear fuel and safe fission energy production. In its fusion part, neutrons are generated in deuterium-tritium (D-T) plasma, confined magnetically in a stellarator-type system with an embedded magnetic mirror. Based on kinetic calculations, the energy balance for such a system is analyzed. Neutron calculations have been performed with the MCNPX code, and the principal design of the reactor part is developed. Neutron outflux at different outer parts of the reactor is calculated. Numerical simulations have been performed on the structure of a magnetic field in a model of the stellarator-mirror device, and that is achieved by switching off one or two coils of toroidal field in the Uragan-2M torsatron. The calculations predict the existence of closed magnetic surfaces under certain conditions. The confinement of fast particles in such a magnetic trap is analyzed.

  15. A gene encoding a protein with a proline-rich domain (MtPPRD1), revealed by suppressive subtractive hybridization (SSH), is specifically expressed in the Medicago truncatula embryo axis during germination.

    Science.gov (United States)

    Bouton, Sophie; Viau, Laure; Lelièvre, Eric; Limami, Anis M

    2005-03-01

    A gene MtPPRD1, encoding a protein of 132 amino acids containing a proline-rich domain (PRD), has been revealed by suppressive subtractive hybridization (SSH) with two mRNA populations of embryo axes harvested immediately before and after radicle emergence. Although at the protein level MtPPRD1 showed low homology with plant lipid transfer proteins (LTPs), it did exhibit the eight cysteine residues conserved in all plant LTPs, a characteristic signature that allows the formation of a hydrophobic cavity adapted for loading hydrophobic molecules. Expression studies of MtPPRD1 have been carried out by quantitative real time RT-PCR throughout germination and post-germination processes in control seeds and seeds in which germination was delayed by abscisic acid (ABA) or the glutamine synthetase inhibitor methionine sulphoximine (MSX) treatments. The results showed that MtPPRD1 expression is developmentally regulated, induced in the embryo axis immediately before radicle emergence, reaches its maximum expression and declines during the early post-germination phase. Organ specificity studies showed that, except for a low and probably constitutive expression in roots, MtPPRD1 is specifically expressed in the embryo axis. Based on both experimental and in silico studies several putative roles are proposed for MtPPRD1 in Medicago truncatula, this protein can intervene (i) as an LTP in membrane biogenesis and regulation of the intracellular fatty acid pool by binding and transferring fatty acids and phospholipids between membranes, (ii) in the control of a developmental process specific to late germination and to early phases of post-germination, and (iii) and/or pathogen defence.

  16. Suppression Subtractive Hybridization (SSH) and its modifications in microbiological research.

    Science.gov (United States)

    Huang, Xiaowei; Li, Yunxia; Niu, Qiuhong; Zhang, Keqin

    2007-09-01

    Suppression subtractive hybridization (SSH) is an effective approach to identify the genes that vary in expression levels during different biological processes. It is often used in higher eukaryotes to study the molecular regulation in complex pathogenic progress, such as tumorigenesis and other chronic multigene-associated diseases. Because microbes have relatively smaller genomes compared with eukaryotes, aside from the analysis at the mRNA level, SSH as well as its modifications have been further employed to isolate specific chromosomal locus, study genomic diversity related with exceptional bacterial secondary metabolisms or genes with special microbial function. This review introduces the SSH and its associated methods and focus on their applications to detect specific functional genes or DNA markers in microorganisms.

  17. Morphological analysis of Japanese quail embryos developed onboard orbital station "Mir" during NASA-"Mir" research program experiments (1990-1996)

    Science.gov (United States)

    Gusev, O.; Gyrieva, T.; Dadasheva, O.; Pahomov, A.; Pirt, C.

    From 1990 to 1996, 5 experiments onboard "MIR" space station which allowed to receive important data dynamics of embryonic development of birds in micro gravitational conditions was carried out by NASA-"MIR" research program, using fertilized eggs of Japanese quail, as convenient object for space experiments. Here we represent the comparative morphomethrical analysis of incubation modes influence on a morphogenesis of Japanese quail. The data allowed us to make the conclusion that the embryonic development of Japanese quail in weightlessness conditions results in authentic decrease of length and body mass parameters in comparison with the embryos, developed in the ground laboratory conditions. The development of a skeleton and extremities, in general developing in normal way, demonstrates decreasing of legs length (10-12%) and body mass (8-12%), but there are no differences in wings length. At the same time we didn't find any significant differences in extremities length in laboratory and synchronic experimental groups of embryos. Analysis didn't show any significant influence of location of eggs in the incubator on mortality of the embryos. The main results of experiments have shown presence of morphometrical changes connected first of all with presence of weightlessness in the surrounded environment. In general, the data a alysis oncen again confirms the assumption that the changed gravity is not an interrupt factor for development of Japanese quail nestlings from fertilized eggs, but further experiments are required for detailed understanding of weightless influence on birds development.

  18. Research Update: Hybrid energy devices combining nanogenerators and energy storage systems for self-charging capability

    Science.gov (United States)

    Kim, Jeonghun; Lee, Ju-Hyuck; Lee, Jaewoo; Yamauchi, Yusuke; Choi, Chang Ho; Kim, Jung Ho

    2017-07-01

    The past decade has been especially creative for nanogenerators as energy harvesting devices utilizing both piezoelectric and triboelectric properties. Most recently, self-charging power units using both nanogenerators and energy storage systems have begun to be investigated for portable and wearable electronics to be used in our daily lives. This review focuses on these hybrid devices with self-charging combined with energy harvesting storage systems based on the most recent reports. In this research update, we will describe the materials, device structures, integration, applications, and research progress up to the present on hybrid devices.

  19. Data Mining: A Hybrid Methodology for Complex and Dynamic Research

    Science.gov (United States)

    Lang, Susan; Baehr, Craig

    2012-01-01

    This article provides an overview of the ways in which data and text mining have potential as research methodologies in composition studies. It introduces data mining in the context of the field of composition studies and discusses ways in which this methodology can complement and extend our existing research practices by blending the best of what…

  20. Data Mining: A Hybrid Methodology for Complex and Dynamic Research

    Science.gov (United States)

    Lang, Susan; Baehr, Craig

    2012-01-01

    This article provides an overview of the ways in which data and text mining have potential as research methodologies in composition studies. It introduces data mining in the context of the field of composition studies and discusses ways in which this methodology can complement and extend our existing research practices by blending the best of what…

  1. Identification of the glycerol kinase gene and its role in diapause embryo restart and early embryo development of Artemia sinica.

    Science.gov (United States)

    Cheng, Cheng; Yao, Feng; Chu, Bing; Li, Xuejie; Liu, Yan; Wu, Yang; Mei, Yanli; Wang, Peisheng; Hou, Lin; Zou, Xiangyang

    2014-03-01

    Glycerol kinase (GK) catalyzes the rate-limiting step in glycerol utilization by transferring a phosphate from ATP to glycerol, yielding glycerol 3-phosphate, which is an important intermediate for both energy metabolism and glycerolipid production. Artemia sinica has an unusual diapause process under stress conditions of high salinity, low temperature and lack of food. In the process, diapause embryos of A. sinica (brine shrimp) accumulate high concentrations of glycerol as a cryoprotectant to prevent low temperature damage to embryos. Upon embryo restart, glycerol is converted into glucose and other carbohydrates. Therefore, GK plays an important role in the diapause embryo restart process. However, the role of GK in diapause termination of embryo development in A. sinica remains unknown. In the present study, a 2096 bp full-length cDNA of gk from A. sinica (As-gk) was obtained, encoding putative 551 amino acids, 60.6 kDa protein. As a crucial enzyme in glycerol uptake and metabolism, GK has been conserved structurally and functionally during evolution. The expression pattern of As-gk was investigated by quantitative real-time PCR and Western blotting. Expression locations of As-gk were analyzed using in situ hybridization. As-gk was widely distributed in the early embryo and several main parts of Artemia after differentiation. The expression of As-GK was also induced by stresses such as cold exposure and high salinity. This initial research into the expression pattern and stress response of GK in Artemia provides a sound basis for further understanding of the function and regulation of genes in early embryonic development in A. sinica and the stress response.

  2. Research on Hybrid Input Mechanical Press Driven by Two Motors

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Given the speed requirements of a mechanical press slider, a differential gear train is adopted instead of the belt and gear drive of a general mechanical press. Two electric motors are used to drive the differential gear train with hybrid input. Based on the working principle of a differential gear train, the angular speed equations and the power distribution equations of the input-output system are established. By controlling the angular speeds of the two motors, the slider can move at different speeds. Taken a JH23-100 type mechanical press as example, the driving system is designed and the power of two motors determined. The simulated results show that the highest slider speed in the mechanical press approaches 39 mm/s only at the forging-punching stage, far less than the 232 mm/s of a general JH23-100 type mechanical press. This provides a new scheme to realize low-speed forging-punching technology from a mechanical press.

  3. Research of the incubation and hybridization instrument with vibration for nanoparticles.

    Science.gov (United States)

    Liu, Zheng; Deng, Yan; Li, Qihua; Liu, Bin; Xia, Yun; Du, Yuhang; He, Nongyue

    2012-11-01

    Nanoparticles are the largest and most widely used nanomaterial in biomedical research nowadays, which are always used in solution. However, traditional techniques, such as hybridization oven are not appropriate for the incubation and hybridization of nanoparticles. Thus designing and developing an effective method and instrument for hybridization of nanoparticles is very essential to solve these present problems. This paper introduced and successfully designed a hybridization instrument, including insulated and closed chamber, temperature control system, motion control system input and output control system. The instrument can not only control temperature precisely to meet various requirements for chemical and biological molecule's incubation and hybridization on nanomaterials, but also make liquid flow slowly and shake according to a certain frequency for mixing to improve hybridization efficiency significantly. The control algorithm of temperature applied PID and fuzzy-PID, the accuracy is improved and stable. Vibration is the most obvious and advantageous feature of the instrument. Furthermore the core control system was improved whose core is C8051F060 MCU and designed into panel.

  4. Evaluation of Bovine Embryo Biopsy Techniques according to Their Ability to Preserve Embryo Viability

    Directory of Open Access Journals (Sweden)

    M. Cenariu

    2012-01-01

    Full Text Available The purpose of this research was to evaluate three embryo biopsy techniques used for preimplantation genetic diagnosis (PGD in cattle and to recommend the least invasive one for current use, especially when PGD is followed by embryo cryopreservation. Three hundred bovine embryos were biopsied by either one of the needle, aspiration or microblade method, and then checked for viability by freezing/thawing and transplantation to recipient cows. The number of pregnancies obtained after the transfer of biopsied frozen/thawed embryos was assessed 30 days later using ultrasounds. The results were significantly different between the three biopsy methods: the pregnancy rate was of 57% in cows that received embryos biopsied by needle, 43% in cows that received embryos biopsied by aspiration, and 31% in cows that received embryos biopsied by microblade. Choosing an adequate biopsy method is therefore of great importance in embryos that will undergo subsequent cryopreservation, as it significantly influences their viability after thawing.

  5. Research Experience with a Plug-In Hybrid Electric Vehicle: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Markel, T.; Pesaran, A.; Kelly, K.; Thornton, M.; Nortman, P.

    2007-12-01

    This technical document reports on the exploratory research conducted by NREL on PHEV technology using a Toyota Prius that has been converted to a plug-in hybrid electric vehicle. The data includes both controlled dynamometer and on-road test results, particularly for hilly driving. The results highlight the petroleum savings and benefits of PHEV technology.

  6. Preliminary Design Study of a Hybrid Airship for Flight Research

    Science.gov (United States)

    Browning, R. G. E.

    1981-01-01

    The feasibility of using components from four small helicopters and an airship envelope as the basis for a quad-rotor research aircraft was studied. Preliminary investigations included a review of candidate hardware and various combinations of rotor craft/airship configurations. A selected vehicle was analyzed to assess its structural and performance characteristics.

  7. Influence of strain of sire on channel x blue F1 hybrid catfish embryo production and fingerling performance under commercial farm conditions.

    Science.gov (United States)

    Channel x blue hybrid catfish is presently the desired aquaculture species in US farm-raised catfish industry. Even though production and performance has improved over the last two decades, several production and performance parameters needs to be improved to maximize the genetic potential of this ...

  8. European Research and Development in Hybrid Flexible Electronics

    Science.gov (United States)

    2010-07-01

    quenching, trapping and annihilation rates of excitons, quantum and conversion efficiencies, photodegradation and device lifetimes, and device...technologies that reduce the production process and cost. Konarka researchers have investigated a variety of systems: dye - sensitized titania solar cells...driven by using pH to modulate metal complexation and decomplexation with optical readout. She also described Grätzel dye -sensitized solar cells in

  9. Novel hybrid FRP tubular columns for sustainable mining infrastructure:Recent research at University of Wollongong

    Institute of Scientific and Technical Information of China (English)

    Yu Tao; Remennikov Alex M.

    2014-01-01

    This paper introduces, for applications in the mining industry, an innovative hybrid column form which consists of an inner steel tube, an outer fibre-reinforced polymer (FRP) tube and an annular concrete infill between them. The two tubes may be concentrically placed to produce a section form more suitable for columns, or eccentrically placed to produce a section form more suitable for beams. The FRP is combined with steel and concrete in these hybrid structural members in such a way that the advantages of FRP are appropriately exploited while its disadvantages are minimized. As a result, these hybrid members pos-sess excellent corrosion resistance as well as excellent ductility and seismic resistance. This paper sum-marizes existing research on this new form of structural members, and discusses their potential applications in mining infrastructure before presenting a summary of the recent and current studies at University of Wollongong (UOW) on their structural behaviour and design.

  10. Inducing chromosome doubling of embryo sac in Populus tomentosa with high temperature exposure for hybrid triploids%高温诱导胚囊染色体加倍获得毛白杨杂种三倍体

    Institute of Scientific and Technical Information of China (English)

    康宁; 白凤莹; 张平冬; 康向阳

    2015-01-01

    advantageous over other methods of breeding in Populus. Given the problem that cross breeding was very difficult in P. tomentosa when using those serious abortive gametes as female parents, P. tomentosa clones 3119, 3532 and 8212 with higher seed setting rate from many years of field observations were selected as female parents, and P. alba × P. glandulosa YX1 as male parent. Before chromosome doubling was carried out, female flower branches should be cultured in water while their pistil development was approaching receptive period, which can overcome the problem that gamete abortion was likely to happen because of malnutrition. During chromosome doubling of embryo sac, female catkins, 4, 16, 28 and 52 h after pollination, were treated for continuous 2 and 4 h by 39 and 42 ℃ high temperature exposure, respectively. And control groups were set without high temperature treatment. In addition, female catkins of P. tomentosa clone 3119 with the same conditions were fixed for paraffin sectioning, sections were observed and the percentages of embryo sac at different developmental stages were statistically counted for determining the correlation between chromosome doubling in embryo sac of P. tomentosa clone 3119 and the development of embryo sac. The results showed that, in total, 458 triploids were produced from the treatments of three cross breeding. Among them, 211 triploids were derived from the cross breeding between clone 3119 and P. alba × P. glandulosa, and the average rate of triploid production was 57. 97% with a total of 230 triploids came from the cross breeding between clone 3532 and P. alba × P. glandulosa, and the average rate of triploid production reached 65. 71%. However, only 17 triploids were screened from the cross breeding between clone 8212 and P. alba × P. glandulosa, with an average rate of triploid production of 70. 83%. No hybrid triploids were obtained in control groups. From the view of effective treating period, P. tomentosa clone 3119 female

  11. The Dark Snow Project: a hybrid research communication program

    Science.gov (United States)

    Box, J. E.; Sinclair, P.

    2015-12-01

    The Dark Snow Project, to crowd fund and communicate Greenland ice-climate interactions expedition research, was a baptism by fire climate communications venture. We did it without a guide book and ran on pure inspiration. Along the way, we acquired quite some of the communication skill set: marketing; social psychology; crowd funding; conventional media; video production; social media.The aim of this presentation is to inventory lessons learned, experience, and resolve recommendations how to do it better for those adventurous enough to do a crowd funded actvity. Key themes are amplifying basic research, engagement in citizen science, outreach, communication.Quickly, one begins thinking of success tactics, like launching news on a Monday instead of a Saturday or keeping the conversation going by telling the story from different and evolving perspectives. The experience taught that unconventional funding is harder won than conventional funding. Yet, because the support came from unconventional sources, the public, we began tapping a large resource in citizen science engagement. If having a compelling call to action such a campaign can be a significant source of sustain. What had also proven difficult was doing it with a small team when each of the following skills demands a larger group; running a media campaign; logistics; video recording and editing; social media promotion; conventional media engagement. The issue and brand awareness grows in a snowball effect encouraging us to run successive annual campaigns.Now in third year, the project can be more effective if upscaling from a single to a multi-cell organization.

  12. Scientists Create Part-Human, Part-Pig Embryo

    Science.gov (United States)

    ... 163262.html Scientists Create Part-Human, Part-Pig Embryo One goal of this stem cell research is ... have successfully used human stem cells to create embryos that are part-human, part-pig. Scientists said ...

  13. Research Regarding the Hybrids Resulted from the Domestic Pig and the Wild Boar

    Directory of Open Access Journals (Sweden)

    Marcel Matiuti

    2010-05-01

    Full Text Available Research was conducted between 2005-2009 in Barzava, Arad county. The villagers breed pigs traditionally, the animals having the freedom to roam the outskirts of the villages. Over the years the domestic sows (Sus scrofa domesticus which had been let by their owners to roam the forests for mast and acorn, have mated with wild boars (Sus scrofa ferus, thus obtaining crossbreeds in various colours – either resembling the female or the male. In Bazava the total number of swine is 1820 specimens out of which 546 is formed by hybrids or crossbreeds in 2009. In the case of these hybrids the length of the head together with that of the trunk can reach 150-170 cm. An adult male can have a weight of 150-200 kg and the female 100-150 kg. These specimens are easily recognizable by the fact that they have the trunk covered in thick, long, spiky hairs. There are also other external characteristics of these crossbreeds. Data has been gathered on what concerns the colour and the length of the hair, external features, maintenance and feeding. Behavioural observations have been made also. The local people appreciate a lot these hybrids because of their qualitative meat, out of which they obtain traditional dishes, combining this meat with that from domestic pigs and veal. Moreover, the maintenance of these hybrids is very low-cost, the only conditions which have to be met being simple shelters during the night and during the winter. The demand for such animals is great. These hybrids are being bought by the Zoos or are used for repopulating the areas in which the wild boars are on the verge of extinction because of excessive poaching. Foreign buyers are also interested in these hybrids, wanting to breed them in special parks and then to organize hunting outings.

  14. Patients' Attitudes towards the Surplus Frozen Embryos in China

    Directory of Open Access Journals (Sweden)

    Xuan Jin

    2013-01-01

    Full Text Available Background. Assisted reproductive techniques have been used in China for more than 20 years. This study investigates the attitudes of surplus embryo holders towards embryos storage and donation for medical research. Methods. A total of 363 couples who had completed in vitro fertilization (IVF treatment and had already had biological children but who still had frozen embryos in storage were invited to participate. Interviews were conducted by clinics in a narrative style. Results. Family size was the major reason for participants’ (discontinuation of embryo storage; moreover, the moral status of embryos was an important factor for couples choosing embryo storage, while the storage fee was an important factor for couples choosing embryo disposal. Most couples discontinued the storage of their embryos once their children were older than 3 years. In our study, 58.8% of the couples preferred to dispose of surplus embryos rather than donate them to research, citing a lack of information and distrust in science as significant reasons for their decision. Conclusions. Interviews regarding frozen embryos, including patients’ expectations for embryo storage and information to assist them with decisions regarding embryo disposal, are beneficial for policies addressing embryo disposition and embryo donation in China.

  15. Research Update: The electronic structure of hybrid perovskite layers and their energetic alignment in devices

    Directory of Open Access Journals (Sweden)

    Selina Olthof

    2016-09-01

    Full Text Available In recent years, the interest in hybrid organic–inorganic perovskites has increased at a rapid pace due to their tremendous success in the field of thin film solar cells. This area closely ties together fundamental solid state research and device application, as it is necessary to understand the basic material properties to optimize the performances and open up new areas of application. In this regard, the energy levels and their respective alignment with adjacent charge transport layers play a crucial role. Currently, we are lacking a detailed understanding about the electronic structure and are struggling to understand what influences the alignment, how it varies, or how it can be intentionally modified. This research update aims at giving an overview over recent results regarding measurements of the electronic structure of hybrid perovskites using photoelectron spectroscopy to summarize the present status.

  16. A digital-analog hybrid system and its application to the automatic flight control system simulation research

    Science.gov (United States)

    1981-01-01

    The characteristics of a digital-analog hybrid system composed of a DJS-8 digital computer and a HMJ-200 analog computer are described as well as its applications to simulation research for an automatic flight control system. A hybrid computational example is included to illustrate the application.

  17. Cryopreservation of manipulated embryos: tackling the double jeopardy.

    Science.gov (United States)

    Dinnyes, A; Nedambale, T L

    2009-01-01

    The aim of the present review is to provide information to researchers and practitioners concerning the reasons for the altered viability and the medium- and long-term consequences of cryopreservation of manipulated mammalian embryos. Embryo manipulation is defined herein as the act or process of manipulating mammalian embryos, including superovulation, AI, IVM, IVF, in vitro culture, intracytoplasmic sperm injection, embryo biopsy or splitting, somatic cell nuclear transfer cloning, the production of sexed embryos (by sperm sexing), embryo cryopreservation, embryo transfer or the creation of genetically modified (transgenic) embryos. With advances in manipulation technologies, the application of embryo manipulation will become more frequent; the proper prevention and management of the resulting alterations will be crucial in establishing an economically viable animal breeding technology.

  18. A new research tool for hybrid Bayesian networks using script language

    Science.gov (United States)

    Sun, Wei; Park, Cheol Young; Carvalho, Rommel

    2011-06-01

    While continuous variables become more and more inevitable in Bayesian networks for modeling real-life applications in complex systems, there are not much software tools to support it. Popular commercial Bayesian network tools such as Hugin, and Netica etc., are either expensive or have to discretize continuous variables. In addition, some free programs existing in the literature, commonly known as BNT, GeNie/SMILE, etc, have their own advantages and disadvantages respectively. In this paper, we introduce a newly developed Java tool for model construction and inference for hybrid Bayesian networks. Via the representation power of the script language, this tool can build the hybrid model automatically based on a well defined string that follows the specific grammars. Furthermore, it implements several inference algorithms capable to accommodate hybrid Bayesian networks, including Junction Tree algorithm (JT) for conditional linear Gaussian model (CLG), and Direct Message Passing (DMP) for general hybrid Bayesian networks with CLG structure. We believe this tool will be useful for researchers in the field.

  19. MULTICRITERIA HYBRID FLOW SHOP SCHEDULING PROBLEM: LITERATURE REVIEW, ANALYSIS, AND FUTURE RESEARCH

    Directory of Open Access Journals (Sweden)

    Marcia de Fatima Morais

    2014-12-01

    Full Text Available This research focuses on the Hybrid Flow Shop production scheduling problem, which is one of the most difficult problems to solve. The literature points to several studies that focus the Hybrid Flow Shop scheduling problem with monocriteria functions. Despite of the fact that, many real world problems involve several objective functions, they can often compete and conflict, leading researchers to concentrate direct their efforts on the development of methods that take consider this variant into consideration. The goal of the study is to review and analyze the methods in order to solve the Hybrid Flow Shop production scheduling problem with multicriteria functions in the literature. The analyses were performed using several papers that have been published over the years, also the parallel machines types, the approach used to develop solution methods, the type of method develop, the objective function, the performance criterion adopted, and the additional constraints considered. The results of the reviewing and analysis of 46 papers showed opportunities for future research on this topic, including the following: (i use uniform and dedicated parallel machines, (ii use exact and metaheuristics approaches, (iv develop lower and uppers bounds, relations of dominance and different search strategies to improve the computational time of the exact methods,  (v develop  other types of metaheuristic, (vi work with anticipatory setups, and (vii add constraints faced by the production systems itself.

  20. Fetos anencefálicos e embriões para pesquisa: sujeitos de direitos? Anencephalic fetuses and research embryos: subjects of rights?

    Directory of Open Access Journals (Sweden)

    Naara Luna

    2009-08-01

    Full Text Available O artigo analisa a emergência de sujeitos sociais em seres antes embutidos na figura materna, depois definidos e circunscritos pela biomedicina: os embriões extracorporais formados por fertilização in vitro e os fetos anencefálicos. Os embriões estiveram no centro de controvérsia nos debates para a aprovação da Lei de Biossegurança, que autorizou o seu uso em pesquisa. Já os fetos anencefálicos foram objeto do debate quanto à possibilidade de ampliação dos permissivos para o aborto. Analisando notícias da grande imprensa, principalmente em levantamento sistemático do jornal O Globo, entre 2000 e 2005, o objetivo é retratar os argumentos que integraram esses debates. Os argumentos que justificam ou recusam o uso de embriões para pesquisa e a antecipação de parto de anencéfalo coincidem em vários pontos porque são tributários da mesma configuração de valores e se fundamentam na figura de pessoa: o indivíduo como valor segundo Dumont.The present article analyzes the emergence of social subjects in the form of beings which had previously been embedded in mother's bodies and which have later become defined and circumscribed by biomedicine: extracorporal embryos, created by in vitro fertilization, and anencephalic fetuses. The embryos were at the center of the controversy regarding their use in scientific research during the debates for the approval of Brazil's new biosecurity law. Anencephalic fetuses became the center of a debate regarding the relaxing of Brazil's abortion laws. This article analyzes mass media news stories provided mostly by a systematic review of articles published in O Globo newspaper between 2000 and 2005 in order to recover the arguments presented in these debates. The arguments to justify or ban embryo research or to anticipate the birth of anencephalic fetuses coincide, in large part, because they are derived from the same value configuration and are founded upon the person: Dumont's individual-as-value.

  1. Electric and Hybrid Vehicle System Research and Development Project: Hybrid Vehicle Potential Assessment. Volume VI. Cost analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, K.S.

    1979-09-30

    The purpose of the cost analysis is to determine the economic feasibility of a variety of hybrid vehicles with respect to conventional vehicles specifically designed for the same duty cycle defined by the mission analysis. Several different hybrid configurations including parallel, parallel-flywheel, and series vehicles were evaluated. The ramifications of incorporating examples of advanced batteries, these being the advanced lead-acid, nickel-zinc, and sodium sulfur were also investigated. Vehicles were specifically designed with these batteries and for the driving cycles specified by the mission. Simulated operation on the missions yielded the energy consumption (petroleum and/or electricity) over the driving cycles. It was concluded that: in the event that gasoline prices reach $2.50 to $3.00/gal, hybrid vehicles in many applications will become economically competitive with conventional vehicles without subsidization; in some commercial applications hybrid vehicles could be economically competitive, when the gasoline price ranges from $1.20 to $1.50/gal. The cost per kWh per cycle of the advanced batteries is much more important economically than the specific energy; the series hybrid vehicles were found to be more expensive in comparison to the parallel or parallel-flywheel hybrids when designed as passenger vehicles; and hybrid vehicles designed for private use could become economically competitive and displace up to 50% of the fuel normally used on that mission if subsidies of $500 to $2000 were supplied to the owner/operator. (LCL)

  2. Formestane、17β-estradiol诱导鸡、鹌鹑胚胎性反转后bcl-2、p53基因的表达差异性研究%On the Expression Differences between bcl-2 and p53 Genes after Sex Reverse in Chicken,Quail and Hybrid Embryos Induced by Formestane and 17β-estradiol

    Institute of Scientific and Technical Information of China (English)

    陈丹盈; 梁耀伟; 赵宗胜; 冯欣璐; 班谦

    2012-01-01

    In this study, using exogenous hormones Formestane and 17β-eslradiol,sex reversal experiments were conducted a-mong chicken, quail and their hybrids embryos,and live embryos of 6 time points (72,96,120,144,168 and 192 h) were then sampled correspondingly. By quantitative PCR.we analyzed expressional differences of bcl-2 and p53 genes of different embryos at different stages after hormone treatment. The results revealed that bcl-2 and p53 gene expression showed no significant difference between normal chicken and quail embryos within heterosexual groups,but compared with chicken and quail embryos,there was significantly difference in hybrid embryos(P<0. 05) ;At 72 h,p53/bcl-2 of male and female embryos of chicken and quail both appeared low gene expression,and meantime, the p53 mRNA expressional quantity fell to relative low point, which indicated that the most embryos' death might happen at this period:gene expressions of bcl-2 and p53 of the chicken and quail embryos injected with Formestane and 17-estradiol were quite different from normal chicken and quail embryos (P<0. 05). But hybrid embryos were all dead at 72 h after they were injected exogenous hormones.%利用外源激素Formestane和17β-estradiol对鸡、鹌鹑及其属间杂交种胚胎进行了性反转实验,并分别采集了72、96、120、144、168、192 h等6个时间点活胚,运用荧光定量PCR法分析了外源激素处理后的不同种胚胎不同时期的bcl-2和p53基因的表达量差异和变化.结果表明:正常鸡和鹌鹑胚种内异性间相比bcl-2和p53基因表达量差异不显著,杂交种胚分别与鸡胚、鹌鹑胚相比,2个基因表达量均差异显著(P<0.05);72 h雌、雄鸡和鹌鹑的胚胎p53/bcl-2表达均出现低谷,此时p53表达同样降至低谷,推测胚胎大批死亡可能是在这个时间段;注射Formestane和17β-estradiol的鸡、鹌鹑胚bcl-2和p53基因表达量分别与未经处理的雌雄鸡胚、雌雄鹌鹑胚比较,差异显著(P<0.0S

  3. Access to global health research. Prevalence and cost of gold and hybrid open access

    Energy Technology Data Exchange (ETDEWEB)

    Haustein, S.; Smith, E.; Mongeon, P.; Shu, F.; Lariviere, V.

    2016-07-01

    As it is a priority of global health research (GHR) to achieve equity in health worldwide, there is an increased demand and expectation that knowledge be shared freely and without barriers. Making research findings available for free to readers by publishing open access (OA) is thus central to GHR. Several studies have assessed the extent to which different forms of OA prevail but despite the importance of free access to knowledge in GHR, particular empirical evidence is missing. This paper aims to fill this gap by analyzing the extent to which GHR papers indexed in PubMed are published OA and how much it costs to publish in gold and hybrid OA journals. Findings show that between 2010 and 2014 as few as 18% of papers were published in gold OA journals, 7% published as hybrid OA (i.e., OA papers in subscription journals), while more than 60% were behind paywalls. Costs for gold OA amounted to $990,619 for 404 papers, whereas $722,631 were spent on article processing charges (APCs) of 223 hybrid papers. The majority of APCs were obtained by large commercial publishing houses known for exorbitant profit margins. (Author)

  4. Teachers Learning to Research Climate: Development of hybrid teacher professional development to support climate inquiry and research in the classroom

    Science.gov (United States)

    Odell, M. R.; Charlevoix, D. J.; Kennedy, T.

    2011-12-01

    The GLOBE Program is an international science and education focused on connecting scientists, teachers and students around relevant, local environmental issues. GLOBE's focus during the next two years in on climate, global change and understanding climate from a scientific perspective. The GLOBE Student Climate Research Campaign (SCRFC) will engage youth from around the world in understanding and researching climate through investigations of local climate challenges. GLOBE teachers are trained in implementation of inquiry in the classroom and the use of scientific data collection protocols to develop inquiry and research projects of the Earth System. In preparation for the SCRC, GLOBE teachers will need additional training in climate science, global change and communicating climate science in the classroom. GLOBE's reach to 111 countries around the world requires development of scalable models for training teachers. In June GLOBE held the first teacher professional development workshop (Learning to Research Summer Institute) in a hybrid format with two-thirds of the teachers participating face-to-face and the remaining teachers participating virtually using Adobe Connect. The week long workshop prepared teachers to integrate climate science inquiry and research projects in the classrooms in the 2011-12 academic year. GLOBE scientists and other climate science experts will work with teachers and their students throughout the year in designing and executing a climate science research project. Final projects and research results will be presented in May 2012 through a virtual conference. This presentation will provide the framework for hybrid teacher professional development in climate science research and inquiry projects as well as summarize the findings from this inaugural session. The GLOBE Program office, headquartered in Boulder, is funded through cooperative agreements with NASA and NOAA with additional support from NSF and the U.S. Department of State. GLOBE

  5. A Hybrid Model Ranking Search Result for Research Paper Searching on Social Bookmarking

    Directory of Open Access Journals (Sweden)

    pijitra jomsri

    2015-11-01

    Full Text Available Social bookmarking and publication sharing systems are essential tools for web resource discovery. The performance and capabilities of search results from research paper bookmarking system are vital. Many researchers use social bookmarking for searching papers related to their topics of interest. This paper proposes a combination of similarity based indexing “tag title and abstract” and static ranking to improve search results. In this particular study, the year of the published paper and type of research paper publication are combined with similarity ranking called (HybridRank. Different weighting scores are employed. The retrieval performance of these weighted combination rankings are evaluated using mean values of NDCG. The results suggest that HybridRank and similarity rank with weight 75:25 has the highest NDCG scores. From the preliminary result of experiment, the combination ranking technique provide more relevant research paper search results. Furthermore the chosen heuristic ranking can improve the efficiency of research paper searching on social bookmarking websites.

  6. Evaluation of hybrid inverters for strategic environmental research and development program applications

    Energy Technology Data Exchange (ETDEWEB)

    Ginn, J.W. [Sandia National Laboratory, Albuquerque, NM (United States)

    1995-11-01

    The photovoltaic systems test facility at Sandia National Laboratories is evaluating the performance of large hybrid power-processing centers (PPC`s). The primary customer for this work has been the Strategic Environmental Research and Development Program (SERDP) of the Department of Defense. One of the goals of SERDP is to develop power-processing hardware to be used in photovoltaic-hybrid power systems at remote military installations. Power for these installations is presently provided by engine-generators. Currently, hardware for twelve such sites is in various stages of procurement. The subject of this talk is testing of the PPC for the first SERDP system, a 300-kW unit for Superior Valley, a US Navy site at China Lake, California.

  7. Research on the Critical Speed of a Mixed-Flow Turbocharger with Hybrid Ceramic Ball Bearing

    Institute of Scientific and Technical Information of China (English)

    HUANG Ruo; GE Xin-bin; MA Chao-chen

    2009-01-01

    The critical speeds for a vehicle turbocharger with hybrid ceramic ball bearing are researched. The ball bearing-rotor system produces resonance when it working in critical speed and that makes the turbocharger injury working for a long time. The calculation and analysis methods of the critical speed for the vehicle turbocharger are described. The critical speed is computed by two methods including Riccati transfer matrix and DyRoBeS finite element method for a vehicle turbocharger with hybrid ceramic ball bearing. The vibration experiment had been taken to validate the calculating result. Comparison between the results by two calculation methods and the test results show that the first critical speed differences are 6.47% and 5.66%, the second critical speed differences are 2.87% and 2.94% respectively. And then, the primary factors which influence the critical speed are analyzed, the conclusions will be helpful for the vehicle turbocharger bearing-rotor system design.

  8. Correlation between embryo morphology and development and chromosomal complement

    Institute of Scientific and Technical Information of China (English)

    Vy Phan; Eva Littman; Dee Harris; Antoine La

    2014-01-01

    Objective: To analyze the correlation between embryo morphology and the chromosomal status using the array comparative genomic hybridization [array comparative genomic hybridization (a-CGH)] technique for screening 23 chromosome pairs in a single blastomere biopsy from Day 3 embryos. Methods: One thousand five hundred and fifty seven embryos were included from 203 cycle ICSI patients undergoing preimplantation genetic screening. The 23 chromosome pairs were analyzed by blastomere biopsy from day 3 embryos using a-CGH array method. Embryo development rate, fragmentation rate and chromosome status of the analyzed blastomeres were recorded and correlated with the aCGH results. Results: The incidence of chromosomal abnormalities was significantly higher in slow-and fast cleaving embryos at day 3 after insemination. The incidence of fragmentation and the type of fragmentation was associated with an increased incidence of chromosomal abnormalities. The symmetry of the blastomeres also correlated with the aneuploidy rates. Conclusions:Embryo development rate and morphological parameter such as degree, type of fragmentation and the symmetry of the blastomeres to a large extent reflect the cytogenetic status of the embryo and thus are important in the selection of embryos with the highest implantation potential.

  9. 文昌鱼胚胎整装荧光原位杂交技术的建立%Whole - mounted fluorescent in situ hybridization of amphioxus embryos

    Institute of Scientific and Technical Information of China (English)

    喻丹; 张培军

    2005-01-01

    文昌鱼(Branchiostoma belcheri tsingtauense)是进化发育生物学研究的重要模式生物,文昌鱼胚胎整装荧光原位杂交(WFISH,whole-mounted fluorescent in situ hybridization)技术将有助于鉴定文昌鱼胚胎发育过程中具有重要调控作用的功能基因.报告了文昌鱼胚胎整装荧光原位杂交技术,用以快速灵敏分析特定基因在文昌鱼胚胎发育过程中的时空表达图式.用体外转录合成的地高辛标记文昌鱼FGFR基因的反义RNA探针,检测到FGFR在文昌鱼原肠胚中表达于发生内陷的中内胚层细胞中,而预定发育为外胚层的细胞不表达FGFR.

  10. Identification of chromosomal errors in human preimplantation embryos with oligonucleotide DNA microarray.

    Directory of Open Access Journals (Sweden)

    Lifeng Liang

    Full Text Available A previous study comparing the performance of different platforms for DNA microarray found that the oligonucleotide (oligo microarray platform containing 385K isothermal probes had the best performance when evaluating dosage sensitivity, precision, specificity, sensitivity and copy number variations border definition. Although oligo microarray platform has been used in some research fields and clinics, it has not been used for aneuploidy screening in human embryos. The present study was designed to use this new microarray platform for preimplantation genetic screening in the human. A total of 383 blastocysts from 72 infertility patients with either advanced maternal age or with previous miscarriage were analyzed after biopsy and microarray. Euploid blastocysts were transferred to patients and clinical pregnancy and implantation rates were measured. Chromosomes in some aneuploid blastocysts were further analyzed by fluorescence in-situ hybridization (FISH to evaluate accuracy of the results. We found that most (58.1% of the blastocysts had chromosomal abnormalities that included single or multiple gains and/or losses of chromosome(s, partial chromosome deletions and/or duplications in both euploid and aneuploid embryos. Transfer of normal euploid blastocysts in 34 cycles resulted in 58.8% clinical pregnancy and 54.4% implantation rates. Examination of abnormal blastocysts by FISH showed that all embryos had matching results comparing microarray and FISH analysis. The present study indicates that oligo microarray conducted with a higher resolution and a greater number of probes is able to detect not only aneuploidy, but also minor chromosomal abnormalities, such as partial chromosome deletion and/or duplication in human embryos. Preimplantation genetic screening of the aneuploidy by DNA microarray is an advanced technology used to select embryos for transfer and improved embryo implantation can be obtained after transfer of the screened normal

  11. Assessment of aneuploidy in human oocytes and preimplantation embryos by chromosome painting

    Energy Technology Data Exchange (ETDEWEB)

    Rougier, N.; Viegas-Pequignot, E.; Plachot, M. [Hospital Necker, Paris (France)] [and others

    1994-09-01

    The poor quality of chromosome preparations often observed after fixation of oocytes and embryos did not usually allow accurate identification of chromosomes involved in non-disjunctions. We, therefore, used chromosome painting to determine the incidence of abnormalities for chromosomes 1 and 7. A total of 50 oocytes inseminated for IVF and showing no signs of fertilization as well as 37 diploid embryos donated for research were fixed according to the Dyban`s technique. Fluorescence in situ hybridization was carried out using whole chromosome painting DNA probes specific for human chromosome 1 and 7. The incidence of aneuploidy was 28%, 10% and 60% for metaphase II, polar body and sperm chromosomes, respectively. The high incidence of aneuploidy observed in sperm prematurely condensed sperm chromosomes is due to the fact that usually far less than 23 sperm chromatids are observed, maybe as a consequence of incomplete chromosome condensation. Thirty seven embryos were analyzed with the same probes. 48% of early embryos were either monosomic 1 or 7 or mosaics comprising blastomeres with 1, 2 or 3 signals. Thus, 8 among the 11 abnormal embryos had hypodiploid cells (25 to 37 chromosomes) indicating either an artefactual loss of chromosomes or a complex anomaly of nuclear division (maltinucleated blastomeres, abnormal migration of chromosomes at anaphase). We therefore calculated a {open_quotes}corrected{close_quotes} incidence of aneuploidy for chromosomes 1 or 7 in early embryos: 18%. 86% of the blastocysts showed mosaicism 2n/3 or 4n as a consequence of the formation of the syncitiotrophoblast. To conclude, chromosome painting is an efficient method to accurately identify chromosomes involved in aneuploidy. This technique should allow us to evaluate the incidence of non-disjunction for all chromosome pairs. Our results confirm the high incidence of chromosome abnormalities occurring as a consequence of meiotic or mitotic non-disjunctions in human oocytes and embryos.

  12. On the possibility of embryo donation in Hispanic America

    OpenAIRE

    Álvarez-Díaz, Jorge Alberto; Médico sexólogo clínico, magíster en bioética. Doctorando en el Programa de Ciencias Sociosanitarias y Humanidades Médicas, Facultad de Medicina, Universidad Complutense de Madrid- España. Becario del Consejo Nacional de Ciencia y Tecnología (CONACYT), México.

    2012-01-01

    Empirical studies regarding embryo donation in developed countries show that the most probable action would be to discard surplus embryos and, if they would donate them, the preferred option would be for research, and eventually to other couples. There are not enough studies in Hispanic America about the opinions of those who have participated in assisted reproductive technologies (ART) regarding embryo disposition of surplus embryos. Moreover, there are scarce specific laws regulating ART in...

  13. Proteomics of early zebrafish embryos

    Directory of Open Access Journals (Sweden)

    Heisenberg Carl-Philipp

    2006-01-01

    Full Text Available Abstract Background Zebrafish (D. rerio has become a powerful and widely used model system for the analysis of vertebrate embryogenesis and organ development. While genetic methods are readily available in zebrafish, protocols for two dimensional (2D gel electrophoresis and proteomics have yet to be developed. Results As a prerequisite to carry out proteomic experiments with early zebrafish embryos, we developed a method to efficiently remove the yolk from large batches of embryos. This method enabled high resolution 2D gel electrophoresis and improved Western blotting considerably. Here, we provide detailed protocols for proteomics in zebrafish from sample preparation to mass spectrometry (MS, including a comparison of databases for MS identification of zebrafish proteins. Conclusion The provided protocols for proteomic analysis of early embryos enable research to be taken in novel directions in embryogenesis.

  14. Culture systems: embryo density.

    Science.gov (United States)

    Reed, Michael L

    2012-01-01

    Embryo density is defined as the embryo-to-volume ratio achieved during in vitro culture; in other words, it is the number of embryos in a defined volume of culture medium. The same density can be achieved by manipulating either the number of embryos in a given volume of medium, or manipulating the volume of the medium for a given number of embryos: for example, a microdrop with five embryos in a 50 μl volume under oil has the same embryo-to-volume ratio (1:10 μl) as a microdrop with one embryo in a 10 μl volume under oil (1:10 μl). Increased embryo density can improve mammalian embryo development in vitro; however, the mechanism(s) responsible for this effect may be different with respect to which method is used to increase embryo density.Standard, flat sterile plastic petri dishes are the most common, traditional platform for embryo culture. Microdrops under a mineral oil overlay can be prepared to control embryo density, but it is critical that dish preparation is consistent, where appropriate techniques are applied to prevent microdrop dehydration during preparation, and results of any data collection are reliable, and repeatable. There are newer dishes available from several manufacturers that are specifically designed for embryo culture; most are readily available for use with human embryos. The concept behind these newer dishes relies on fabrication of conical and smaller volume wells into the dish design, so that embryos rest at the lowest point in the wells, and where putative embryotrophic factors may concentrate.Embryo density is not usually considered by the embryologist as a technique in and of itself; rather, the decision to culture embryos in groups or individually is protocol-driven, and is based more on convenience or the need to collect data on individual embryos. Embryo density can be controlled, and as such, it can be utilized as a simple, yet effective tool to improve in vitro development of human embryos.

  15. Thoughts and Practice on Some Problems about Research and Application of Two-Line Hybrid Rice

    Directory of Open Access Journals (Sweden)

    Li-yun CHEN

    2011-06-01

    Full Text Available The main problems about research and application of two-line hybrid rice were reviewed, including the confusing nomenclature and male sterile lines classification, the unclear characteristics of photoperiod and temperature responses and the unsuitable site selection for male sterile line and hybrid rice seed production. In order to efficiently and accurately use dual-purpose genic male sterile lines, four types, including PTGMS (photo-thermo-sensitive genic male sterile rice, TGMS (thermo-sensitive genic male sterile rice, reverse PTGMS and reverse TGMS, were proposed. A new idea for explaining the mechanism of sterility in dual-purpose hybrid rice was proposed. The transition from sterile to fertile was involved in the cooperative regulation of major-effect sterile genes and photoperiod and/or temperature sensitive ones. The minor-effect genes with accumulative effect on sterility were important factors that affected the critical temperature of sterility transfer. In order to make better use of dual-purpose lines, the characterization of responses to photoperiod and temperature of PTGMS should be made and the identification method for the characterization of photoperiod and temperature responses of PTGMS should also be put forward. The optimal ecological site for seed production could be determined according to the historical climate data and the requirements for the meteorological conditions during the different periods of seed production.

  16. Thoughts and Practice on Some Problems about Research and Application of Two-Line Hybrid Rice

    Institute of Scientific and Technical Information of China (English)

    CHEN Li-yun; LEI Dong-yang; TANG Wen-bang; XIAO Ying-hui

    2011-01-01

    The main problems about research and application of two-line hybrid rice were reviewed,including the confusing nomenclature and male sterile lines classification,the unclear characteristics of photoperiod and temperature responses and the unsuitable site selection for male sterile line and hybrid rice seed production.In order to efficiently and accurately use dual-purpose genic male sterile lines,four types,including PTGMS (photo-thermo-sensitive genic male sterile rice),TGMS (thermo-sensitive genic male sterile rice),reverse PTGMS and reverse TGMS,were proposed.A new idea for explaining the mechanism of sterility in dual-purpose hybrid rice was proposed.The transition from sterile to fertile was involved in the cooperative regulation of major-effect sterile genes and photoperiod and/or temperature sensitive ones.The minor-effect genes with accumulative effect on sterility were important factors that affected the critical temperature of sterility transfer.In order to make better use of dual-purpose lines,the charecterization of responses to photoperiod and temperature of PTGMS should be made and the identification method for the characterization of photoperiod and temperature responses of PTGMS should also be put forward.The optimal ecological site for seed production could be determined according to the historical climate data and the requirements for the meteorological conditions during the different periods of seed production.

  17. siRNA Specific to Pdx-1 Disturbed the Formation of the Islet in Early Zebrafish Embryos

    Institute of Scientific and Technical Information of China (English)

    CHEN Shen; HUANG Jintao; YUAN Guangnfing; CHEN Qian; HUANG Nannan; XIE Fukang

    2007-01-01

    Pdx-1, an important transcription factor highlighting in the early pancreatic development,islet functions and pancreatic disorders, needs to be more investigated in zebrafish, and siRNA is still seldom applied in zebrafish embryo-related research.Our aim was to explore the role of pdx-1 in pan-creatic development of zebrafish embryos by using siRNA approach. Microinjection, reverse tran-scriptase-PCR (RT-PCR), in situ hybridization and immunofluorescent staining were used in this re-search, and the morphology of the islet in normal zebrafish embryos, and in those treated with the siRNA specific to pdx-1 (siPDX-1) or siGFP was observed and compared. The expression of pdx-1 was detected in the stages of 1-cell, 2-cell, 4-cell, 8-cell, 16-cell, 16-hour by RT-PCT. The in situ hy-bridization and immunofluorescent staining results showed that siPDX-I disturbed the formation of the islet in zebrafish embryos. Pdx-1 played multiple roles in maintaining the phenotype of the islet during embryogenesis in zebrafish.

  18. Aspect of Dynamic Simulation and Experimental Research Studies on Hybrid Pneumatic Power System

    Directory of Open Access Journals (Sweden)

    K. David Huang

    2010-01-01

    Full Text Available A Hybrid Pneumatic Power System (HPPS has been developed for several years with the major aim of reducing the vehicle fuel consumption, environment pollution and enhancing the vehicle performance as well. Comparing with the conventional hybrid system, HPPS replaces the battery's electrochemical energy with a high-pressure air storage tank and enables the internal combustion engine (ICE to function at its sweet spot. Besides, the HPPS, which effectively merges both the high-pressure air flow from the storage tank and the recycled exhaust flow from the ICE, thereby increases the thermal efficiency of the ICE and transforms the merged flow energy into mechanical energy using a high-efficiency turbine. This paper focuses on the major research process into HPPSs, including overall dynamic simulation and experimental validation. By using the simulation tool ITI-Sim, this research demonstrates an experiment which can be operated precisely according to the requirements of various driving conditions under which a car actually runs on the road in accordance with the regulated running vehicle test mode. HPPS is expected to increase the performance of the entire system from 15% to 39%, and is likely to replace the traditional system in the coming years.

  19. Bovine in vitro embryo production : An overview

    Directory of Open Access Journals (Sweden)

    V. S. Suthar

    Full Text Available Dairy industry perfected the application of the first reproductive biotechnology, i.e. artificial insemination (AI - a great success story and also remains the user of embryo transfer technology (ETT. In addition, recently the researchers taking interest to embraced the field of Transvaginal OocyteRecovery (TVOR and in vitro production (IVEP of embryos. IVF provides the starting point for the generation of reproductive material for a number of advanced reproduction techniques including sperm microinjection and nuclear transfer (cloning. In several countries commercial IVF facilities are already being employed by cattle ET operators. Various research groups have reported on modification of TVOR technique to give greater efficiency. Much research is still needed in domestic animal (Especially Indian species on mechanisms controlling embryo development and on development of totally in vitro system for embryo culture. [Vet World 2009; 2(12.000: 478-479`

  20. Software Development Technologies for Reactive, Real-Time, and Hybrid Systems: Summary of Research

    Science.gov (United States)

    Manna, Zohar

    1998-01-01

    This research is directed towards the implementation of a comprehensive deductive-algorithmic environment (toolkit) for the development and verification of high assurance reactive systems, especially concurrent, real-time, and hybrid systems. For this, we have designed and implemented the STCP (Stanford Temporal Prover) verification system. Reactive systems have an ongoing interaction with their environment, and their computations are infinite sequences of states. A large number of systems can be seen as reactive systems, including hardware, concurrent programs, network protocols, and embedded systems. Temporal logic provides a convenient language for expressing properties of reactive systems. A temporal verification methodology provides procedures for proving that a given system satisfies a given temporal property. The research covered necessary theoretical foundations as well as implementation and application issues.

  1. A Hybrid EAV-Relational Model for Consistent and Scalable Capture of Clinical Research Data.

    Science.gov (United States)

    Khan, Omar; Lim Choi Keung, Sarah N; Zhao, Lei; Arvanitis, Theodoros N

    2014-01-01

    Many clinical research databases are built for specific purposes and their design is often guided by the requirements of their particular setting. Not only does this lead to issues of interoperability and reusability between research groups in the wider community but, within the project itself, changes and additions to the system could be implemented using an ad hoc approach, which may make the system difficult to maintain and even more difficult to share. In this paper, we outline a hybrid Entity-Attribute-Value and relational model approach for modelling data, in light of frequently changing requirements, which enables the back-end database schema to remain static, improving the extensibility and scalability of an application. The model also facilitates data reuse. The methods used build on the modular architecture previously introduced in the CURe project.

  2. The Jet Propulsion Laboratory Electric and Hybrid Vehicle System Research and Development Project, 1977-1984: A Review

    Science.gov (United States)

    Kurtz, D.; Roan, V.

    1985-01-01

    The JPL Electric and Hybrid Vehicle System Research and Development Project was established in the spring of 1977. Originally administered by the Energy Research and Development Administration (ERDA) and later by the Electric and Hybrid Vehicle Division of the U.S. Department of Energy (DOE), the overall Program objective was to decrease this nation's dependence on foreign petroleum sources by developing the technologies and incentives necessary to bring electric and hybrid vehicles successfully into the marketplace. The ERDA/DOE Program structure was divided into two major elements: (1) technology research and system development and (2) field demonstration and market development. The Jet Propulsion Laboratory (JPL) has been one of several field centers supporting the former Program element. In that capacity, the specific historical areas of responsibility have been: (1) Vehicle system developments (2) System integration and test (3) Supporting subsystem development (4) System assessments (5) Simulation tool development.

  3. Research on Operation Principle and Control of Novel Hybrid Excitation Bearingless Permanent Magnet Generator

    Directory of Open Access Journals (Sweden)

    Huangqiu Zhu

    2016-08-01

    Full Text Available Under the condition of load changing, the magnetic field of traditional permanent magnet generators (PMG is hard to be adjusted, and the mechanical bearings are significantly worn. To overcome the drawbacks above, a novel hybrid excitation bearingless permanent magnet generator (HEBPMG is proposed in this paper, which has integrated the merits of hybrid excitation permanent magnet generators and magnetic bearings. Firstly, the structure and winding configuration of the HEBPMG are introduced, and then the principles of radial suspension and power generation are presented. The suspension principle as well as power generation principle is analyzed in this paper. Then, the flux linkage and induced voltage equations are derived, and the accurate mathematical model of radial suspension force is built based on the Maxwell tensor method. Subsequently, by means of the finite element analysis software-ANSYS Maxwell, the corresponding electromagnetic characteristics are analyzed to verify the correctness of the mentioned models. In addition, a compensation control strategy based on flux-linkage observation is proposed to solve the problems of unstable suspension force and generating voltage under variable load condition in this paper. Meanwhile, the corresponding control system is constructed and its feasibility is validated by simulation results. Finally, an experimental prototype of a 2.2 kW HEBPMG is tested. Experimental researches show that the HEBPMG can operate steadily under variable load condition and possess good suspension performance and power generation quality.

  4. Review and Prospect on Japonica Hybrid Rice Research in Anhui Province, China

    Institute of Scientific and Technical Information of China (English)

    LI Cheng-quan; WANG Shou-hai; WANG De-zheng; LUO Yan-chang; ZHANG Pei-jiang; WU Shuang; DU Shi-yun; XU Chuan-wan

    2005-01-01

    The breeding history and commercial exploitation of japonica hybrid rice in Anhui Province, China over the last threedecades were reviewed. Besides, the bottleneck problems restricting the development of japonica hybrid rice in China weresummarized, and corresponding technological countermeasures were proposed.

  5. Donation of surplus frozen embryos for stem cell research or fertility treatment-should medical professionals and healthcare institutions be allowed to exercise undue influence on the informed decision of their former patients?

    Science.gov (United States)

    Heng, Boon Chin

    2006-01-01

    The increasing availability of clinical assisted reproduction has led to an accumulated surplus of frozen embryos within fertility clinics worldwide. Couples that have attained success in clinical assisted reproduction, and have no further desire to reproduce; are often faced with an agonizing dilemma on what to do with their surplus frozen embryos-whether to simply discard them, or donate either for scientific research or to other infertile couples. There is a risk that persons or institutions directly involved in procuring donated embryos will prioritize their own interests over the informed choice of the patient to donate either for scientific research or to other infertile couples. Very often, formerly infertile couples who have attained reproductive success feel an overwhelming sense of gratitude to the fertility doctor handling their treatment. Hence, there is a risk of medical professionals exercising undue influence on their former patients, to sway the final decision to their preferred outcome. In the private practice setting, the preferred outcome would likely be donation for the treatment of other infertile couples; whilst in the case of medical professionals affiliated with research or academic institutions, the preferred outcome would likely be donation for stem cell research.

  6. Fusion-Fission Research Facility (FFRF) as a Practical Step Toward Hybrids

    Energy Technology Data Exchange (ETDEWEB)

    L. Zakharov, J. Li and Y. Wu

    2010-11-18

    The project of ASIPP (with PPPL participation), called FFRF, (R/a=4/1 m/m, Ipl=5 MA, Btor=4-6 T, PDT=50-100 MW, Pfission=80-4000 MW, 1 m thick blanket) is outlined. FFRF stands for the Fusion-Fission Research Facility with a unique fusion mission and a pioneering mission of merging fusion and fission for accumulation of design, experimental, and operational data for future hybrid applications. The design of FFRF will use as much as possible the EAST and ITER design experience. On the other hand, FFRF strongly relies on new, Lithium Wall Fusion plasma regimes, the development of which has already started in the US and China.

  7. 预防OHSS行全胚冷冻的临床研究%Clinical research of all embryo freezing to prevent OHSS

    Institute of Scientific and Technical Information of China (English)

    任建枝; 沙爱国; 李萍; 韩冬梅; 耿洁; 马彩辉

    2012-01-01

    目的 探讨在辅助生育技术过程中出现卵巢过度刺激综合征(OHSS)倾向患者进行全胚冷冻,以预防OHSS发生,后进行冷冻胚胎移植的应用价值.方法 选择2009年1月至2010年12月在本中心进行ART患者,共取卵1722周期,其中具有OHSS倾向患者201周期,占总取卵周期的11.67%,分极高危OHSS倾向组和高危OHSS倾向组两组.极高危OHSS倾向组给予全部胚胎冷冻,以后再安排冷冻胚胎移植,对于高危OHSS倾向组给予新鲜胚胎移植.比较促排卵药的使用总量及使用天数、HCG日E2水平、平均获卵数、平均胚胎数、平均优质胚胎数、OHSS发生率情况.比较全部胚胎冷冻进行复苏后移植与新鲜胚胎移植比较平均移植胚胎数、平均移植优质胚胎数、妊娠率、着床率、早期流产率等.结果1.两组患者的平均年龄、不孕年限、促排卵药的使用总量和天数无显著性差异;但全胚冷冻组HCG日E2水平、平均获卵数、平均胚胎数、平均优质胚胎数及OHSS发生率均高于新鲜周期移植组.2.全胚冷冻后行冷冻胚胎移植组与新鲜周期移植组的平均移植胚胎数、平均移植优质胚胎数、妊娠率、着床率、早期流产率均无显著性差异.结论 1.全胚冷冻不能减少早发型OHSS发生;2.为预防OHSS行全胎冷冻后,再行冷冻胚移植不影响不孕症患者治疗结局.%Objective: To explore utilisation of elective cryopreservation of all embryos for the patients at high risk of ovarian hy-perstimulation syndrome (OHSS) to prevent OHSS in assisted reproduction therapy (ART) , and report on reproductive outcome following transfer of thawed embryos. Methods: A retrospective analysis of all ART cycles carried out between January 2009 and December 2010. 1722 oocyte retrievals were performed, all high risk for OHSS from 201 retrievals ( 11. 67% ) were divided into critical or severe risk OHSS group. All embryos were electively cryopreserved and

  8. Heteroparental blastocyst production from microsurgically corrected tripronucleated human embryos.

    Science.gov (United States)

    Escribá, María-José; Martín, Julio; Rubio, Carmen; Valbuena, Diana; Remohí, José; Pellicer, Antonio; Simón, Carlos

    2006-12-01

    To prove the efficiency of identification and removal of one of the surplus paternal pronuclei in dispermic IVF zygotes to obtain heteroparental blastocysts. Experimental. One hundred fourteen tripronucleated (3PN) embryos from conventional IVF. After informed and signed consent, the patients from Instituto Valenciano Infertilidad (IVI), Valencia, donated their abnormally fertilized embryos. Seventy-two embryos were diploidized by microsurgical removal of the pronucleus located at the farthest position to the second polar body. Forty-two 3PN embryos served as controls. Survival and correction rate; in vitro development up to the blastocyst stage; X, Y, and 18 chromosome determination by triple fluorescent in situ hybridization and, inheritance analysis for 10 polymorphic repeat regions using polymerase chain reaction (PCR) amplification and sequencing. Seventy-eight percent of 3PN zygotes (56/72) survived manipulation and eventually 51 zygotes had two pronuclei (71%). Forty-one percent of manipulated embryos progressed in vitro to the blastocyst stage (21/51). Fluorescent in situ hybridization analysis performed on eight manipulated embryos confirmed their diploid state; all four controls were triploid. Heteroparental inheritances were also confirmed in four of six manipulated embryos. Heteroparental blastocysts can be derived from corrected dispermic zygotes.

  9. The HFEA public consultation process on hybrids and chimeras: informed, effective, and meaningful?

    Science.gov (United States)

    Baylis, Françoise

    2009-03-01

    In September 2007, the Human Fertilisation and Embryology Authority (HFEA) in the United Kingdom concluded that "there is no fundamental reason to prevent cytoplasmic hybrid research ... this area of research can, with caution and careful scrutiny, be permitted." Later, in January 2008, HFEA issued two research licenses to create humanesque cytoplasmic hybrid embryos from which stem cells could be derived. This article critically examines the public consultation process that preceded these decisions, concluding that the process was flawed and demonstrating how the HFEA documents summarizing the findings of the public consultation process misrepresent the public's contributions to this policymaking initiative.

  10. Optimization of the core configuration design using a hybrid artificial intelligence algorithm for research reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hedayat, Afshin, E-mail: ahedayat@aut.ac.i [Department of Nuclear Engineering and Physics, Amirkabir University of Technology (Tehran Polytechnic), 424 Hafez Avenue, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Reactor Research and Development School, Nuclear Science and Technology Research Institute (NSTRI), End of North Karegar Street, P.O. Box 14395-836, Tehran (Iran, Islamic Republic of); Davilu, Hadi [Department of Nuclear Engineering and Physics, Amirkabir University of Technology (Tehran Polytechnic), 424 Hafez Avenue, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Barfrosh, Ahmad Abdollahzadeh [Department of Computer Engineering, Amirkabir University of Technology (Tehran Polytechnic), 424 Hafez Avenue, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Sepanloo, Kamran [Reactor Research and Development School, Nuclear Science and Technology Research Institute (NSTRI), End of North Karegar Street, P.O. Box 14395-836, Tehran (Iran, Islamic Republic of)

    2009-12-15

    To successfully carry out material irradiation experiments and radioisotope productions, a high thermal neutron flux at irradiation box over a desired life time of a core configuration is needed. On the other hand, reactor safety and operational constraints must be preserved during core configuration selection. Two main objectives and two safety and operational constraints are suggested to optimize reactor core configuration design. Suggested parameters and conditions are considered as two separate fitness functions composed of two main objectives and two penalty functions. This is a constrained and combinatorial type of a multi-objective optimization problem. In this paper, a fast and effective hybrid artificial intelligence algorithm is introduced and developed to reach a Pareto optimal set. The hybrid algorithm is composed of a fast and elitist multi-objective genetic algorithm (GA) and a fast fitness function evaluating system based on the cascade feed forward artificial neural networks (ANNs). A specific GA representation of core configuration and also special GA operators are introduced and used to overcome the combinatorial constraints of this optimization problem. A software package (Core Pattern Calculator 1) is developed to prepare and reform required data for ANNs training and also to revise the optimization results. Some practical test parameters and conditions are suggested to adjust main parameters of the hybrid algorithm. Results show that introduced ANNs can be trained and estimate selected core parameters of a research reactor very quickly. It improves effectively optimization process. Final optimization results show that a uniform and dense diversity of Pareto fronts are gained over a wide range of fitness function values. To take a more careful selection of Pareto optimal solutions, a revision system is introduced and used. The revision of gained Pareto optimal set is performed by using developed software package. Also some secondary operational

  11. The Two Faces of Security in Hybrid Political Orders: A Framework for Analysis and Research

    Directory of Open Access Journals (Sweden)

    Robin Luckham

    2013-09-01

    authority and capacity to deliver security are weak, disputed or compromised by special interests; and (iii “securitised policy spaces” in which international actors collaborate to ensure peace and fulfil their responsibility to protect vulnerable end-users in unsecured regions. In making these distinctions we argue that similar analytical lenses can be turned upon international actors in securitised policy spaces as well as upon state and non-state security actors. The concluding section argues that such a reframing of the security and development debate demands not just new modes of analysis but also fresh approaches to research designed both to provide insights into the vernacular understandings, coping strategies and potential agency of end-users and to uncover the informal networks, alliances and covert strategies of the multiple actors determining their security in hybrid political orders. This paper builds upon a systematic literature search undertaken by the Justice and Security Research Programme (JSRP at the London School of Economics (LSE funded by the UK’s Department for International Development (DFID. The search itself and its main findings are discussed in Luckham and Kirk (2012 and Luckham and Kirk (2013.

  12. Electroporation into Cultured Mammalian Embryos

    Science.gov (United States)

    Nomura, Tadashi; Takahashi, Masanori; Osumi, Noriko

    Over the last century, mammalian embryos have been used extensively as a common animal model to investigate fundamental questions in the field of developmental biology. More recently, the establishment of transgenic and gene-targeting systems in laboratory mice has enabled researchers to unveil the genetic mechanisms under lying complex developmental processes (Mak, 2007). However, our understanding of cell—cell interactions and their molecular basis in the early stages of mammalian embryogenesis is still very fragmentary. One of the major problems is the difficulty of precise manipulation and limited accessibility to mammalian embryos via uterus wall. Unfortunately, existing tissue and organotypic culture systems per se do not fully recapitulate three-dimensional, dynamic processes of organogenesis observed in vivo. Although transgenic animal technology and virus-mediated gene delivery are useful to manipulate gene expression, these techniques take much time and financial costs, which limit their use.

  13. Research on Hybrid Isolation System for Micro-Nano-Fabrication Platform

    Directory of Open Access Journals (Sweden)

    Jie Fu

    2014-06-01

    Full Text Available In order to obtain better vibration suppression effect, this paper designs a semiactive/fully active hybrid isolator by using magnetorheological elastomer (MRE and piezoelectric material. Combined with multimode control scheme, full frequency vibration suppression is achieved. Firstly, series type structure is determined for the hybrid isolator, and the structure of hybrid isolator is designed. Next, the dynamic model of hybrid isolator is derived, the dynamic characteristics measurement for MRE isolator and piezoelectric stack actuator (PSA is established, and parameters such as voltage-displacement coefficient, stiffness and damping constant are identified from the experimental results, respectively. Meanwhile, the switch frequency is determined by experimental results of PSA and MRE isolator. Lastly, influence of the stiffness of MRE, control voltage of PSA, and intermediate mass on hybrid isolator system is analyzed by simulations, and the results show that the hybrid isolator proposed is effective.

  14. Hybrid Rice Research and Development in China and Its New Progress

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Hybrid rice's history and its development up to date are described in the paper. Compared with the conventional rice, hybrid rice can increase grain yield by about 20%. Hybrid rice breeding in China has been advancing along the three-line method, to two-line method, to super high-yielding rice application strategically and its success in higher degree will be seen by the utilization of distant heterosis cooperated with biotechnology.

  15. Promising sour cherry hybrids (Prunus cerasus L. developed at Fruit Research Institute Čačak

    Directory of Open Access Journals (Sweden)

    Radičević Sanja

    2010-01-01

    Full Text Available At Fruit Research Institute in Čačak, major objectives of the work on breeding new sour cherry (Prunus cerasus L. cultivars are high cropping, large, high-quality fruits and resistance to causal agents of diseases and pests. As a result of the planned hybridization, more than 10,000 hybrid seedlings have been developed from about 40 cultivars within more than 110 parental combinations, among which are 'Čačanski rubin' ('Shasse Morello' x 'Köröser Weichsel' and 'Šumadinka' ('Köröser Weichsel' x 'Heimanns Konserven Weichsel' which have been named and released. Ten-year study of 11 hybrids, selected from the population of about 3,000 hybrid seedlings, gave four hybrids which have been singled out as elite (III/23, III/31, II/40 i XII/57. These hybrids are currently under procedure of being released as new cultivars. The paper presents two-year results of the study of ripening time, pomological properties, biochemical composition of fruits, and field resistance to causal agents of diseases and pests attacking the above named genotypes which were compared to standard cultivar 'Heimanns Konserven Weichsel'. In the studied hybrids, fruit weight, soluble solids content and sugars content were higher than in standard cultivar. In addition, they exhibit substantial field resistance to causal agents of brown rot (Monilinia laxa /Ader et Ruhl./ Honey ex Whetz., cherry leaf spot (Blumeriella jaapii (Rehm. v. Arx., shot-hole (Clasterosporium carpophilum (Lév. Aderh. and cherry fruit fly (Rhagoletis cerasi L. attack.

  16. Electric and Hybrid Vehicle System Research and Development Project: Hybrid Vehicle Potential Assessment. Volume IV. Series systems

    Energy Technology Data Exchange (ETDEWEB)

    Popinski, Z.

    1979-09-30

    In the Hybrid Vehicle Potential Assessment Task three major powertrain configurations (parallel, parallel with flywheel, and series) were studied. An evaluation of the series configuration is presented. The series configuration has the advantage that the engine is mechanically uncoupled from the wheels and can be operated at its best economy point much of the time. The mechanical energy produced by the engine is converted through a generator into electrical energy which is used to drive the motor or charge the batteries. This configuration offers a good degree of flexibility. It has the disadvantage that substantial losses of energy occur since the mechanical energy from the engine passes through several components before being used to drive the wheels. The energy produced by the engine is reduced by the product of efficiencies of components connected in series. Trade-offs involved in the study of the series configuration were directed toward establishing the size of the engine, motor and generator to meet vehicle acceleration performance; determining what level to operate the engine, and determining when to use the battery. These results were then used in the electric range simulation.

  17. Embryo-maternal communication

    DEFF Research Database (Denmark)

    Østrup, Esben; Hyttel, Poul; Østrup, Olga

    2011-01-01

    Communication during early pregnancy is essential for successful reproduction. In this review we address the beginning of the communication between mother and developing embryo; including morphological and transcriptional changes in the endometrium as well as epigenetic regulation mechanisms...... directing the placentation. An increasing knowledge of the embryo-maternal communication might not only help to improve the fertility of our farm animals but also our understanding of human health and reproduction....

  18. Manipulation and imaging of Kryptolebias marmoratus embryos.

    Science.gov (United States)

    Mourabit, Sulayman; Kudoh, Tetsuhiro

    2012-12-01

    The self-fertilizing mangrove killifish, Kryptolebias marmoratus, is an upcoming model species for a range of biological disciplines. To further establish this model in the field of developmental biology, we examined several techniques for embryonic manipulation and for imaging that can be used in an array of experimental designs. These methodological approaches can be divided into two categories: handling of embryos with and without their chorionic membrane. Embryos still enclosed in their chorion can be manipulated using an agarose bed or a methyl cellulose system, holding them in place and allowing their rotation to more specific angles and positions. Using these methods, we demonstrate microinjection of embryos and monitoring of fluorescent yolk syncytial nuclei (YSN) using both stereo and compound microscopes. For higher magnification imaging using compound microscopes as well as time-lapse analyses, embryos were dechorionated and embedded in low-melting-point agarose. To demonstrate this embedding technique, we further examined fluorescent YSN and also analyzed the yolk surface of K. marmoratus embryos. The latter was observed to provide an excellent imaging platform for study of the behavior and morphology of cells during embryonic development, for various types of cells. Our data demonstrate that K. marmoratus is an excellent model species for research in developmental biology, as methodological approaches for the manipulation and imaging of embryos are efficient and readily available.

  19. Embryo disposition and the new death scene

    Directory of Open Access Journals (Sweden)

    Ellison, David

    2011-01-01

    Full Text Available In the IVF clinic - a place designed principally for the production and implantation of embryos - scientists and IVF recipients are faced with decisions regarding the disposition of frozen embryos. At this time there are hundred of thousands of cryopreserved embryos awaiting such determinations. They may be thawed for transfer to the woman herself, they may be donated for research or for use by other infertile couples, they may remain in frozen storage, or they may variously be discarded by being allowed to 'succumb', or 'perish'. Where the choice is discard, some IVF clients have chosen to formalise the process through ceremony. A new language is emerging in response to the desires of the would-be-parents who might wish to characterise the discard experience as a ‘good death’. This article examines the procedure known as ‘compassionate transfer’ where the embryo to be discarded is placed in the woman’s vagina where it is clear that it will not develop further. An alternate method has the embryo transferred in the usual manner but without the benefit of fertility-enhancing hormones at a point in the cycle unreceptive to implantation. The embryo destined for disposal is thus removed from the realm of technological possibility and ‘returned’ to the female body for a homely death. While debates continue about whether or not embryos constitute life, new practices are developing in response to the emotional experience of embryo discard. We argue that compassionate transfer is a death scene taking shape. In this article, we take the measure of this new death scene’s fabrication, and consider the form, significance, and legal complexity of its ceremonies.

  20. Microfluidic system with integrated microinjector for automated Drosophila embryo injection.

    Science.gov (United States)

    Delubac, Daniel; Highley, Christopher B; Witzberger-Krajcovic, Melissa; Ayoob, Joseph C; Furbee, Emily C; Minden, Jonathan S; Zappe, Stefan

    2012-11-21

    Drosophila is one of the most important model organisms in biology. Knowledge derived from the recently sequenced 12 genomes of various Drosophila species can today be combined with the results of more than 100 years of research to systematically investigate Drosophila biology at the molecular level. In order to enable automated, high-throughput manipulation of Drosophila embryos, we have developed a microfluidic system based on a Pyrex-silicon-Pyrex sandwich structure with integrated, surface-micromachined silicon nitride injector for automated injection of reagents. Our system automatically retrieves embryos from an external reservoir, separates potentially clustered embryos through a sheath flow mechanisms, passively aligns an embryo with the integrated injector through geometric constraints, and pushes the embryo onto the injector through flow drag forces. Automated detection of an embryo at injection position through an external camera triggers injection of reagents and subsequent ejection of the embryo to an external reservoir. Our technology can support automated screens based on Drosophila embryos as well as creation of transgenic Drosophila lines. Apart from Drosophila embryos, the layout of our system can be easily modified to accommodate injection of oocytes, embryos, larvae, or adults of other species and fills an important technological gap with regard to automated manipulation of multicellular organisms.

  1. Determination of gene expression patterns using high-throughput RNA in situ hybridizaion to whole-mount Drosophila embryos

    Energy Technology Data Exchange (ETDEWEB)

    Weiszmann, R.; Hammonds, A.S.; Celniker, S.E.

    2009-04-09

    We describe a high-throughput protocol for RNA in situ hybridization (ISH) to Drosophila embryos in a 96-well format. cDNA or genomic DNA templates are amplified by PCR and then digoxigenin-labeled ribonucleotides are incorporated into antisense RNA probes by in vitro transcription. The quality of each probe is evaluated before ISH using a RNA probe quantification (dot blot) assay. RNA probes are hybridized to fixed, mixed-staged Drosophila embryos in 96-well plates. The resulting stained embryos can be examined and photographed immediately or stored at 4oC for later analysis. Starting with fixed, staged embryos, the protocol takes 6 d from probe template production through hybridization. Preparation of fixed embryos requires a minimum of 2 weeks to collect embryos representing all stages. The method has been used to determine the expression patterns of over 6,000 genes throughout embryogenesis.

  2. Transgenic manipulation of plant embryo sacs tracked through cell-type-specific fluorescent markers: cell labeling, cell ablation, and adventitious embryos.

    Science.gov (United States)

    Lawit, Shai J; Chamberlin, Mark A; Agee, April; Caswell, Eric S; Albertsen, Marc C

    2013-06-01

    Expression datasets relating to the Arabidopsis female gametophyte have enabled the creation of a tool set which allows simultaneous visual tracking of each specific cell type (egg, synergids, central cell, and antipodals). This cell-specific, fluorescent labeling tool-set functions from gametophyte cellularization through fertilization and early embryo development. Using this system, cell fates were tracked within Arabidopsis ovules following molecular manipulations, such as the ablation of the egg and/or synergids. Upon egg cell ablation, it was observed that a synergid can switch its developmental fate to become egg/embryo-like upon loss of the native egg. Also, manipulated was the fate of the somatic ovular cells, which can become egg- and embryo-like, reminiscent of adventitious embryony. These advances represent initial steps toward engineering synthetic apomixis resulting in seed derived wholly from the maternal plant. The end goal of applied apomixis research, fixing important agronomic traits such as hybrid vigor, would be a key benefit to agricultural productivity.

  3. Membrane/distillation hybrid process research and development. Final report, phase II

    Energy Technology Data Exchange (ETDEWEB)

    Mazanec, T.J.

    1997-07-01

    This report covers work conducted under the grant awarded to BP by DOE in late 1991 entitled {open_quotes}Membrane/Distillation Hybrid Process Research and Development.{close_quotes} The program was directed towards development and commercialization of the BP process for separation of vapor phase olefins from non-olefins via facilitated transport using an aqueous facilitator. The program has come to a very successful conclusion, with formation of a partnership between BP and Stone and Webster Engineering Corporation (SWEC) to market and commercialize the technology. The focus of this report is the final portion of the program, during which engineering re-design, facilitator optimization, economic analysis, and marketing have been the primary activities. At the end of Phase II BP was looking to partner with an engineering firm to advance the selective olefin recovery (SOR) technology from the lab/demo stage to full commercialization. In August 1995 BP and SWEC reached an agreement to advance the technology by completing additional Phase III work with DOE and beginning marketing activities.

  4. Comparative genome research between maize and rice using genomic in situ hybridization

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Using the genomic DNAs of maize and rice as probes respectively,the homology of maize and rice genomes was assessed by genomic in situ hybridization. When rice genomic DNAs were hybridized to maize, all chromosomes displayed many multiple discrete regions, while each rice chromosome delineated a single consecutive chromosomal region after they were hybridized with maize genomic DNAs. The results indicate that the genomes of maize and rice share high homology, and confirm the proposal that maize and rice are diverged from a common ancestor.

  5. Development of a new clinically applicable device for embryo evaluation which measures embryo oxygen consumption.

    Science.gov (United States)

    Kurosawa, Hiroki; Utsunomiya, Hiroki; Shiga, Naomi; Takahashi, Aiko; Ihara, Motomasa; Ishibashi, Masumi; Nishimoto, Mitsuo; Watanabe, Zen; Abe, Hiroyuki; Kumagai, Jin; Terada, Yukihiro; Igarashi, Hideki; Takahashi, Toshifumi; Fukui, Atsushi; Suganuma, Ryota; Tachibana, Masahito; Yaegashi, Nobuo

    2016-10-01

    Does a new system-the chip-sensing embryo respiration monitoring system (CERMs)-enable evaluation of embryo viability for potential application in a clinical IVF setting? The system enabled the oxygen consumption rate of spheroids, bovine embryos and frozen-thawed human embryos to be measured, and this rate corresponded to the developmental potential of embryos. To date, no reliable and clinically suitable objective evaluation methods for embryos are available, which circumvent the differences in inter-observer subjective view. Existing systems such as the scanning electrochemical microscopy (SECM) technique, which enables the measurement of oxygen consumption rate in embryos, need improvement in usability before they can be applied to a clinical setting. This is a prospective original research study. The feasibility of measuring the oxygen consumption rate was assessed using CERMs for 9 spheroids, 9 bovine embryos and 30 redundant frozen-thawed human embryos. The endpoints for the study were whether CERMs could detect a dissolved oxygen gradient with high sensitivity, had comparable accuracy to the SECM measuring system with improved usability, and could predict the development of an embryo to a blastocyst by measuring the oxygen consumption rate. The relationship between the oxygen consumption rate and standard morphological evaluation was also examined. We developed a new CERMs, which enables the oxygen consumption rate to be measured automatically using an electrochemical method. The device was initially used for measuring a dissolved oxygen concentration gradient in order to calculate oxygen consumption rate using nine spheroids. Next, we evaluated data correlation between the CERMs and the SECM measuring systems using nine bovine embryos. Finally, the oxygen consumption rates of 30 human embryos, which were frozen-thawed on 2nd day after fertilization, were measured by CERMs at 6, 24, 48, 72 and 96 h after thawing with standard morphological evaluation

  6. 进口奶牛胚胎移植效果的研究%Research on the Embryos Transfer Effect of Imported Dairy Cattle

    Institute of Scientific and Technical Information of China (English)

    薛建华; 吴胜权; 麻柱; 赵鹏; 宣柏华; 朱玉林; 李艳华; 吕小青

    2011-01-01

    2007年5月8日至2010年11月9日以来,笔者在北京奶牛中心良种场及中国农机院小王庄牛场移植进口奶牛胚胎.引进美、加系优质荷斯坦奶牛胚胎的目的是选育优秀后备种公牛和建立种子母牛群.截止2010年11月,累计使用胚胎369枚,移植受体牛367头,妊娠212头,平均移植妊娠率为60.40%.移植结果说明,本研究成功建立了一套先进的进口胚胎移植方法.%From May 8, 2007 to November 9, 2010, we transferred imported dairy cattle embryos in Breeding Farm of Beijing Dairy Cattle Center and Xiao Wang Zhuang of China Agricultural Machinery Institute. The entrance of holstein embryos from the United States and Canada were used to cultivate and breed superior bulls and cows of Holstein. Up to November 2010, total 369 embryos were used and 367 receptor cows were transplanted(with 15 cows not yet reached the pregnancy examination time), of which 212 were pregnant, so the average pregnancy rate was 60.40%. The transplantation results illustrated that we have established a set of advanced technology for imported embryo transfer technology.

  7. Fertilization and Embryo Development in Hybridization between Avena magna and Avena nuda%四倍体大燕麦与六倍体裸燕麦的受精作用和胚胎发育

    Institute of Scientific and Technical Information of China (English)

    赵云云; 刘家熙; 杨才

    2001-01-01

    用石蜡切片法,对四倍体大燕麦(Avena magna L.)和六倍体裸燕麦(Avena nuda L.)杂交的受精作用和胚胎发育进行了观察。结果表明,六倍体裸燕麦花粉在四倍体大燕麦柱头上萌发良好,花粉管可顺利长入花柱和胚囊。观察的168个四倍体大燕麦子房中,2.38%发生了双受精,产生了胚和胚乳;1.79%发生了单卵受精,只产生胚乳而无胚;总受精率为5.36%;成胚率为4.17%。由于胚乳的缺乏或发育异常及败育,最终难以获得有生活力的种子。为四倍体大燕麦和六倍体裸燕麦杂交提供了细胞胚胎学证据。%Observations were made on the fertilization and early embryo development in intergeneric cross between Avena magna and Avena nuda. The pollen germination of Avena nada appeared to be normal on the stigma of Avena magna and the pollen tubes grew into the style and entered the embryo sacs. In 168 florets fixed after pollination, 2.38% had double fertilization and produced embryo and endosperm, but the endosperm development was slower than that of the embryo, 1.79% had only embryo and 1.19% had only endosperm. The frequency of fertilization and embryo formation were 5.36% and 4.17% respectively. Due to the lack of endosperm or its abnormal development and abortion, no viable seeds were poduced. Cytoembryological evidence was provided for crosses between Avena magna and Avena nuda.

  8. Investigative Research, FMECA and PHM Modeling of Hybrid-Electric Distributed Propulsion System Architectures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Hybrid-Electric distributed propulsion (HEDP) is becoming widely accepted and new tools will be required for future development with validation and demonstrations...

  9. The human embryo in the Christian tradition: a reconsideration.

    Science.gov (United States)

    Jones, D A

    2005-12-01

    Recent claims that the Christian tradition justifies destructive research on human embryos have drawn upon an article by the late Professor Gordon Dunstan which appeared in this journal in 1984. Despite its undoubted influence, this article was flawed and seriously misrepresented the tradition of Christian reflection on the moral status of the human embryo.

  10. [First birth after preimplantation genetic diagnosis performed on thawed embryos].

    Science.gov (United States)

    Frydman, N; Ray, P; Romana, S; Fanchin, R; Lelorc'h, M; Kerbrat, V; Frydman, R; Tachdjian, G

    2003-06-01

    To report the birth of the first infant conceived after preimplantation genetic diagnosis (PGD) performed on frozen-thawed embryos in our PGD center. Three couples (C1, C2 and C3) who had frozen embryos from a previous in vitro fertilization attempt were enrolled in our PGD program. Embryos were thawed one day before the biopsy procedure for the couples C1 and C3 and the day of the biopsy for the couple C2. The single cell genetic analysis was performed by a multiplex PCR for the couple C1 and by fluorescent in situ hybridization for the couples C2 and C3. The embryos transfers were carried out on the third or fourth day. Out of ten thawed embryos, eight were biopsied and five were transferred during three embryos transfers. Two biochemical and one ongoing pregnancy were obtained yielded one birth. PGD may be offered to couples at risk of transmission of a serious and incurable genetic disease and having frozen embryos.

  11. Hybrid upper surface blown flap propulsive-lift concept for the Quiet Short-Haul Research Aircraft

    Science.gov (United States)

    Cochrane, J. A.; Carros, R. J.

    1975-01-01

    The hybrid upper surface blowing concept consists of wing-mounted turbofan engines with a major portion of the fan exhaust directed over the wing upper surface to provide high levels of propulsive lift, but with a portion of the fan airflow directed over selected portions of the airframe to provide boundary layer control. NASA-sponsored preliminary design studies identified the hybrid upper surface blowing concept as the best propulsive lift concept to be applied to the Quiet Short-Haul Research Aircraft (QSRA) that is planned as a flight facility to conduct flight research at low noise levels, high approach lift coefficients, and steep approaches. Data from NASA in-house and NASA-sponsored small and large-scale wind tunnel tests of various configurations using this concept are presented.

  12. Oxygen diffusion in fish embryos

    NARCIS (Netherlands)

    Kranenbarg, S.

    2002-01-01

    All vertebrate embryos pass through a developmental period of remarkably low morphological variability. This period has been called phylotypic period. During the phylotypic period, organogenesis takes place, including blood vessel development. Before the phylotypic period, the embryos

  13. The First Human Cloned Embryo.

    Science.gov (United States)

    Cibelli, Jose B.; Lanza, Robert P.; West, Michael D.; Ezzell, Carol

    2002-01-01

    Describes a process known as parthenogenesis which produces cloned, early-stage embryos and human embryos generated only from eggs. Speculates that this technology puts therapeutic cloning within reach. (DDR)

  14. Multiplex detection of RNA expression in Drosophila embryos.

    Science.gov (United States)

    Kosman, Dave; Mizutani, Claudia M; Lemons, Derek; Cox, W Gregory; McGinnis, William; Bier, Ethan

    2004-08-06

    We present a fluorescence-based, multiplex in situ hybridization method that permits the simultaneous detection of five differently labeled antisense RNA probes and up to seven differ-ent transcripts in a single Drosophila embryo. We also show that it should be possible to increase the number of detected transcripts substantially with nascent transcript multiplex fluorescent in situ hybridization. These multiplex methods fill a current technological gap between high-resolution in situ hybridization with one or two fluorescently labeled probes and low-resolution but genome-wide microarray RNA profiling and should be of great utility in establishing gene networks.

  15. Biosensors for detecting stress in developing embryos

    Science.gov (United States)

    Purdey, Malcolm S.; Saini, Avishkar; McLennan, Hanna J.; Pullen, Benjamin J.; Schartner, Erik P.; Sutton-McDowall, Melanie L.; Thompson, Jeremy G.; Monro, Tanya M.; Nicholls, Stephen J.; Abell, Andrew D.

    2016-12-01

    Reactive Oxygen Species (ROS) cause DNA damage and defective function in sperm and also affects the developmental competence of embryos. It is therefore critical to monitor ROS in sperm, oocytes and developing embryos. In particular, hydrogen peroxide (H2O2) is a ROS important to normal cell function and signalling as well as its role in oxidative stress. Here we report the development of a fluorescent sensor for H2O2 using carboxyperoxyfluor-1 (CPF1) in solution and attached to a glass slide or multi-mode optical fibre. CPF1 increases in fluorescence upon reaction with H2O2 to non-invasively detect H2O2 near developing embryos. These probes are constructed by immobilising CPF1 to the optical fibre tip a polyacrylamide layer. Also reported is a new dual optical fibre sensor for detecting both H2O2 and pH that is functional at biologically concentrations of H2O2 and can sense pH to 0.1 units. This research shows promise for the use of optical fibre sensors for monitoring the health of developing embryos. Furthermore, these sensors are applicable for use beyond embryos such as detecting stress in endothelial cells involved in cardiovascular dysfunction.

  16. Ovarian stimulation and embryo quality

    NARCIS (Netherlands)

    Baart, Esther; Macklon, Nick S.; Fauser, Bart J. C. M.

    2009-01-01

    To Study the effects of different ovarian stimulation approaches on oocyte and embryo quality, it is imperative to assess embryo quality with a reliable and objective method. Embryos rated as high quality by standardized morphological assessment are associated with higher implantation and pregnancy

  17. Research on performance of hybrid organic dyes-sensitized solar cell

    Institute of Scientific and Technical Information of China (English)

    Lei Sun; Weizheng Yuan; Dayong Qiao

    2006-01-01

    The hybrid sensitizer rhodamine B and coumarin or eosin and coumarin is used to sensitize nanocrystalline porous films. Absorption of the nanocrystalline photovoltaic cell (NPC) is improved in visible light. The performance of these cells is more effective than that of cells sensitized only by sensitizer rhodamine B or eosin. In the simulative solar light, cell sensitized by hybrid sensitizer rhodamine B and coumarin can get open circuit voltage (Voc) of 550 mV and short circuit current (Isc) of 0.1375 mA/cm2.

  18. Research on Fuel Consumption of Hybrid Bulldozer under Typical Duty Cycle

    Science.gov (United States)

    Song, Qiang; Wang, Wen-Jun; Jia, Chao; Yao, You-Liang; Wang, Sheng-Bo

    The hybrid drive bulldozer adopts a dual-motor independent drive system with engine-generator assembly as its power source. The mathematical model of the whole system is constructed on the software platform of MATLAB/Simulink. And then according to the velocity data gained from a real test experiment, a typical duty cycle is build up. Finally the fuel consumption of the bulldozer is calculated under this duty-cycle. Simulation results show that, compared with the traditional mechanical one, the hybrid electric drive system can save fuel up to 16% and therefore indicates great potential for lifting up fuel economy.

  19. A Qualitative Experiment: Research on Mediated Meaning Construction Using a Hybrid Approach

    Science.gov (United States)

    Robinson, Sue; Mendelson, Andrew L.

    2012-01-01

    This article presents a hybrid methodological technique that fuses elements of experimental design with qualitative strategies to explore mediated communication. Called the "qualitative experiment," this strategy uses focus groups and in-depth interviews "within" randomized stimulus conditions typically associated with…

  20. Researching Hybrid Learning Communities in the Digital Age through Educational Ethnography

    Science.gov (United States)

    James, Nalita; Busher, Hugh

    2013-01-01

    This paper discusses the complexities of investigating the experiences of participants in hybrid (online/offline) learning communities through educational ethnography. In these communities, people construct small cultures in the liminal spaces or "border crossings" between the virtually real and "actually" real, using computer-mediated and…

  1. Hybrid striped bass National Breeding Program: Research towards genetic improvement of a non-model species

    Science.gov (United States)

    The hybrid striped bass (HSB) farming industry at present relies almost totally on wild broodstock for annual production of larvae and fingerlings, and industry efforts to domesticate the parent species of the HSB (white bass: WB, Morone chrysops; striped bass: SB, M. saxatilis) have been fairly lim...

  2. The integrated HIV-1 provirus in patient sperm chromosome and its transfer into the early embryo by fertilization.

    Directory of Open Access Journals (Sweden)

    Dian Wang

    Full Text Available Complete understanding of the route of HIV-1 transmission is an important prerequisite for curbing the HIV/AIDS pandemic. So far, the known routes of HIV-1 transmission include sexual contact, needle sharing, puncture, transfusion and mother-to-child transmission. Whether HIV can be vertically transmitted from human sperm to embryo by fertilization is largely undetermined. Direct research on embryo derived from infected human sperm and healthy human ova have been difficult because of ethical issues and problems in the collection of ova. However, the use of inter-specific in vitro fertilization (IVF between human sperm and hamster ova can avoid both of these problems. Combined with molecular, cytogenetical and immunological techniques such as the preparation of human sperm chromosomes, fluorescent in situ hybridization (FISH, and immunofluorescence assay (IFA, this study mainly explored whether any integrated HIV provirus were present in the chromosomes of infected patients' sperm, and whether that provirus could be transferred into early embryos by fertilization and maintain its function of replication and expression. Evidence showed that HIV-1 nucleic acid was present in the spermatozoa of HIV/AIDS patients, that HIV-1 provirus is present on the patient sperm chromosome, that the integrated provirus could be transferred into early embryo chromosomally integrated by fertilization, and that it could replicate alongside the embryonic genome and subsequently express its protein in the embryo. These findings indicate the possibility of vertical transmission of HIV-1 from the sperm genome to the embryonic genome by fertilization. This study also offers a platform for the research into this new mode of transmission for other viruses, especially sexually transmitted viruses.

  3. Research on the aerodynamic characteristics of a lift drag hybrid vertical axis wind turbine

    Directory of Open Access Journals (Sweden)

    Xiaojing Sun

    2016-01-01

    Full Text Available Compared with a drag-type vertical axis wind turbines, one of the greatest advantages for a lift-type vertical axis wind turbines is its higher power coefficient (Cp. However, the lift-type vertical axis wind turbines is not a self-starting turbine as its starting torque is very low. In order to combine the advantage of both the drag-type and the lift-type vertical axis wind turbines, a lift drag hybrid vertical axis wind turbines was designed in this article and its aerodynamics and starting performance was studied in detail with the aid of computational fluid dynamics simulations. Numerical results indicate that the power coefficient of this lift drag hybrid vertical axis wind turbines declines when the distance between its drag-type blades and the center of rotation of the turbine rotor increases, whereas its starting torque can be significantly improved. Studies also show that unlike the lift-type vertical axis wind turbines, this lift drag hybrid-type vertical axis wind turbines could be able to solve the problem of low start-up torque. However, the installation position of the drag blade is very important. If the drag blade is mounted very close to the spindle, the starting torque of the lift drag hybrid-type vertical axis wind turbines may not be improved at all. In addition, it has been found that the power coefficient of the studied vertical axis wind turbines is not as good as expected and possible reasons have been provided in this article after the pressure distribution along the surfaces of the airfoil-shaped blades of the hybrid turbine was analyzed.

  4. Research progress of hybrid UV curing%混杂紫外光固化研究进展

    Institute of Scientific and Technical Information of China (English)

    刘红波; 吴宗南

    2009-01-01

    The recent research progress and application of hybrid UV curing at home and abroad were reviewed.The free radical-cationic hybrid UV curing of acrylate-epoxy and acrylate-vinyl ether system,free radical-free radical hybrid UV curing,UV-heat, UV-air and UV-moisture curing were included.The cured products had better comprehensive properties by the hybird curing methods.%综述了近年国内外混杂紫外光固化研究的进展和应用情况.其中包括丙烯酸酯-环氧树脂体系、丙烯酸酯-乙烯基醚体系的自由基-阳离子混杂光固化,自由基-自由基体系混杂固化,光-热、光-空气及光-潮气混杂固化等.这些混杂固化方式使固化产物的综合性能更为优异.

  5. In vivo embryo production in buffalo: present and perspectives

    Directory of Open Access Journals (Sweden)

    S. Tyagi

    2010-02-01

    Full Text Available Buffaloes constitute a significant part of the domestic stock and contribute very significantly in the rural economy, especially in South and South-East Asia. Embryo transfer technique (ETT, a proven tool for faster multiplication of desired genetic resource has been satisfactorily used for cattle and is being adopted for buffalo. Following very limited research in buffalo, the viable embryo production has increased significantly from less than 1 per flushing to 2.5-3.0 in general and over 4 in isolated cases and conception rate following embryo transfer improved from about 10% to about 30-40%. However, response to superovulatory treatments and recovery of viable embryos following superovulation is still low compared to cattle due to various factors. This paper deals with the present success rate and information on some of the factors affecting in vivo embryo production, and future possibilities to make this technique more efficient and economic for wider use, in buffalo.

  6. Splitting embryos on the slippery slope: ethics and public policy.

    Science.gov (United States)

    Macklin, Ruth

    1994-09-01

    Neither the George Washington University embryo splitting experiment nor the technique of embryo splitting itself has ethical flaws. The experiment harmed or wronged no one, and the investigators followed intramural review procedures for the experiment, although some might fault them for failing to seek extramural consultation or for not waiting until national guidelines for research on preembryos were developed. Ethical objections to such cloning on the basis of possible loss of individuality, possible lessening of individual worth, and concern about potential harm to the resulting children are discussed and challenged, as are objections to the creation of embryos for the purpose of genetic diagnosis. Many of the ethical questions raised by the George Washington experiment are similar to those posed by existing reproductive technologies that allow the simultaneous production of several embryos. A multidisciplinary group should consider whether regulation of cloning is needed, and laws should be enacted to prohibit a commercial market for all frozen embryos.

  7. Debating elective single embryo transfer after in vitro fertilization: a ...

    African Journals Online (AJOL)

    Debating elective single embryo transfer after in vitro fertilization: a plea for a context sensitive approach. ... Annals of Medical and Health Sciences Research ... and create an ethical dilemma for physicians: Should the physician do as the ...

  8. Sexing bovine pre-implantation embryos using the polymerase ...

    African Journals Online (AJOL)

    Yomi

    2012-03-06

    Mar 6, 2012 ... polymerase chain reaction: A model for human embryo ... Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine ... obtain and there is no ethical issue related to their use for research.

  9. Hybrid simulation research on formation mechanism of tungsten nanostructure induced by helium plasma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Atsushi M., E-mail: ito.atsushi@nifs.ac.jp [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan); Takayama, Arimichi; Oda, Yasuhiro [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan); Tamura, Tomoyuki; Kobayashi, Ryo; Hattori, Tatsunori; Ogata, Shuji [Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Ohno, Noriyasu; Kajita, Shin [Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Yajima, Miyuki [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan); Noiri, Yasuyuki [Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Yoshimoto, Yoshihide [University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Saito, Seiki [Kushiro National College of Technology, Kushiro, Hokkaido 084-0916 (Japan); Takamura, Shuichi [Aichi Institute of Technology, 1247 Yachigusa, Yakusa-cho, Toyota 470-0392 (Japan); Murashima, Takahiro [Tohoku University, 6-3, Aramaki-Aza-Aoba, Aoba-Ward, Sendai 980-8578 (Japan); Miyamoto, Mitsutaka [Shimane University, Matsue, Shimane 690-8504 (Japan); Nakamura, Hiroaki [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan); Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)

    2015-08-15

    The generation of tungsten fuzzy nanostructure by exposure to helium plasma is one of the important problems for the use of tungsten material as divertor plates in nuclear fusion reactors. In the present paper, the formation mechanisms of the helium bubble and the tungsten fuzzy nanostructure were investigated by using several simulation methods. We proposed the four-step process which is composed of penetration step, diffusion and agglomeration step, helium bubble growth step, and fuzzy nanostructure formation step. As the fourth step, the formation of the tungsten fuzzy nanostructure was successfully reproduced by newly developed hybrid simulation combining between molecular dynamics and Monte-Carlo method. The formation mechanism of tungsten fuzzy nanostructure observed by the hybrid simulation is that concavity and convexity of the surface are enhanced by the bursting of helium bubbles in the region around the concavity.

  10. Research on hybrid power filter of 6 kV power grid in coal mine

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-feng; LI Jian

    2010-01-01

    Studied the harmonic control of the 6 kV power grid in a coal mine substation.Taking harmonic suppression and reactive power compensation into account, and complying with the economic and efficient technical line of the smart grid, a new hybrid active filter was proposed and applied to the power grid in the coal mine with the advantages such as large capacity, low cost and low loss. In order to improve detection speed and reduce the succeeding errors to improve the filtering performance of the active power filter,the DFT (Discrete Fourier Transform) sliding window algorithm based on coordinate transformation and improved hysteresis control method was proposed. The Matlab simulation results show that the hybrid active filter is satisfactory, can improve the grid power factor and can meet the requirements of improving the power quality in the coal mine.

  11. Hybrid simulation research on formation mechanism of tungsten nanostructure induced by helium plasma irradiation

    Science.gov (United States)

    Ito, Atsushi M.; Takayama, Arimichi; Oda, Yasuhiro; Tamura, Tomoyuki; Kobayashi, Ryo; Hattori, Tatsunori; Ogata, Shuji; Ohno, Noriyasu; Kajita, Shin; Yajima, Miyuki; Noiri, Yasuyuki; Yoshimoto, Yoshihide; Saito, Seiki; Takamura, Shuichi; Murashima, Takahiro; Miyamoto, Mitsutaka; Nakamura, Hiroaki

    2015-08-01

    The generation of tungsten fuzzy nanostructure by exposure to helium plasma is one of the important problems for the use of tungsten material as divertor plates in nuclear fusion reactors. In the present paper, the formation mechanisms of the helium bubble and the tungsten fuzzy nanostructure were investigated by using several simulation methods. We proposed the four-step process which is composed of penetration step, diffusion and agglomeration step, helium bubble growth step, and fuzzy nanostructure formation step. As the fourth step, the formation of the tungsten fuzzy nanostructure was successfully reproduced by newly developed hybrid simulation combining between molecular dynamics and Monte-Carlo method. The formation mechanism of tungsten fuzzy nanostructure observed by the hybrid simulation is that concavity and convexity of the surface are enhanced by the bursting of helium bubbles in the region around the concavity.

  12. Embryo implantation: A time for recalling and forwarding

    Institute of Scientific and Technical Information of China (English)

    CHEN Qi; PENG HongYing; ZHANG Ying; LEI Li; CAO YuJing; Duan EnKui

    2009-01-01

    The success of embryo implantation is a critical step towards further embryo development and pregnancy outcome.The observations and investigations on embryo implantation have been over a century.A huge body of knowledge has been accumulated in anatomy,histology,ultrastructure and hormonal regulation; as well as recently in depth information about molecular signaling pathways got from studies of genomic wide gene screening and specific gene deletion.The knowledge from basic research has also substantially helped to initiate and improve the Artificial Reproductive Technology (ART) in clinical applications.Now we've known that the normal embryo implantation involves the embryo's development into an implantation-competent blastocyst and the synchronized transformation of uteri into a receptive stage.The interdependent relationship between the blastocyst and uterus involves complicated hormonal regulation and local paracrine,juxtacrine interactions.In this paper,we review some important historical findings regarding uterine receptivity and blastocyst activation,as well as some less discussed topics such as embryo spacing,embryo orientation.Further understandings on detailed mechanisms during the process of embryo implantation will help cure women infertility as well as develop new generation of non-steroids contraceptives.

  13. Mouse embryo manipulations with OCT guidance

    Science.gov (United States)

    Garcia, Monica D.; Syed, Saba H.; Coughlin, Andrew J.; Wang, Shang; West, Jennifer L.; Larin, Kirill V.; Larina, Irina V.

    2014-03-01

    Optical coherence tomography (OCT) is a three-dimensional, non-invasive optical imaging technique that relies on low-coherence interferometry. OCT has the capability of imaging 2 - 3 mm into tissue, which enables imaging of deeper structures within the embryo with a relatively high spatial resolution (2 - 15μm). Within the past decade, OCT has been increasingly used as a live imaging tool for embryonic cardiovascular research in several animal models. Research in our lab has recently shown that OCT can be used in combination with embryo culture for the visualization of early mammalian cardiovascular development (E7.5 - E10.0). Here, we demonstrate that OCT can be used for the guided microinjection of gold-silica nanoshell suspension into the cardiovascular system in live embryos without deleterious effect. This approach shows a promising application for the OCT guided delivery of contrast agents, viral vectors, therapeutic or pharmacological agents, signaling molecules or dyes to specific organ systems or tissues in live embryos and demonstrates a great potential for gold-silica nanoshells as a contrast agent in embryonic studies.

  14. Research Update: Hybrid organic-inorganic perovskite (HOIP thin films and solar cells by vapor phase reaction

    Directory of Open Access Journals (Sweden)

    Po-Shen Shen

    2016-09-01

    Full Text Available With the rapid progress in deposition techniques for hybrid organic-inorganic perovskite (HOIP thin films, this new class of photovoltaic (PV technology has achieved material quality and power conversion efficiency comparable to those established technologies. Among the various techniques for HOIP thin films preparation, vapor based deposition technique is considered as a promising alternative process to substitute solution spin-coating method for large-area or scale-up preparation. This technique provides some unique benefits for high-quality perovskite crystallization, which are discussed in this research update.

  15. Research Update: Hybrid organic-inorganic perovskite (HOIP) thin films and solar cells by vapor phase reaction

    Science.gov (United States)

    Shen, Po-Shen; Chiang, Yu-Hsien; Li, Ming-Hsien; Guo, Tzung-Fang; Chen, Peter

    2016-09-01

    With the rapid progress in deposition techniques for hybrid organic-inorganic perovskite (HOIP) thin films, this new class of photovoltaic (PV) technology has achieved material quality and power conversion efficiency comparable to those established technologies. Among the various techniques for HOIP thin films preparation, vapor based deposition technique is considered as a promising alternative process to substitute solution spin-coating method for large-area or scale-up preparation. This technique provides some unique benefits for high-quality perovskite crystallization, which are discussed in this research update.

  16. Application of Hybrid Real-Time Power System Simulator for Designing and Researching of Relay Protection and Automation

    Science.gov (United States)

    Borovikov, Yu S.; Sulaymanov, A. O.; Andreev, M. V.

    2015-10-01

    Development, research and operation of smart grids (SG) with active-adaptive networks (AAS) are actual tasks for today. Planned integration of high-speed FACTS devices greatly complicates complex dynamic properties of power systems. As a result the operating conditions of equipment of power systems are significantly changing. Such situation creates the new actual problem of development and research of relay protection and automation (RPA) which will be able to adequately operate in the SGs and adapt to its regimes. Effectiveness of solution of the problem depends on using tools - different simulators of electric power systems. Analysis of the most famous and widely exploited simulators led to the conclusion about the impossibility of using them for solution of the mentioned problem. In Tomsk Polytechnic University developed the prototype of hybrid multiprocessor software and hardware system - Hybrid Real-Time Power System Simulator (HRTSim). Because of its unique features this simulator can be used for solution of mentioned tasks. This article introduces the concept of development and research of relay protection and automation with usage of HRTSim.

  17. Arts-Based Research: Trojan Horses and Shibboleths. The Liabilities of a Hybrid Research Approach. "What Hath Eisner Wrought?"

    Science.gov (United States)

    Pariser, David

    2009-01-01

    The term "arts-based research" has been debated for some time now. In an article strongly in favor of this approach Bean (2007) identifies three species: "Research on the arts (italics in the original) (art history, visual and cultural studies, media studies etc.)...Research for the arts, refers to research into applied techniques, materials and…

  18. Research Needs for Fusion-Fission Hybrid Systems. Report of the Research Needs Workshop (ReNeW) Gaithersburg, Maryland, September 30 - October 2, 2009

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-09-30

    Largely in anticipation of a possible nuclear renaissance, there has been an enthusiastic renewal of interest in the fusion-fission hybrid concept, driven primarily by some members of the fusion community. A fusion-fission hybrid consists of a neutron-producing fusion core surrounded by a fission blanket. Hybrids are of interest because of their potential to address the main long-term sustainability issues related to nuclear power: fuel supply, energy production, and waste management. As a result of this renewed interest, the U.S. Department of Energy (DOE), with the participation of the Office of Fusion Energy Sciences (OFES), Office of Nuclear Energy (NE), and National Nuclear Security Administration (NNSA), organized a three-day workshop in Gaithersburg, Maryland, from September 30 through October 2, 2009. Participants identified several goals. At the highest level, it was recognized that DOE does not currently support any R&D in the area of fusion-fission hybrids. The question to be addressed was whether or not hybrids offer sufficient promise to motivate DOE to initiate an R&D program in this area. At the next level, the workshop participants were asked to define the research needs and resources required to move the fusion-fission concept forward. The answer to the high-level question was given in two ways. On the one hand, when viewed as a standalone concept, the fusion-fission hybrid does indeed offer the promise of being able to address the sustainability issues associated with conventional nuclear power. On the other hand, when participants were asked whether these hybrid solutions are potentially more attractive than contemplated pure fission solutions (that is, fast burners and fast breeders), there was general consensus that this question could not be quantitatively answered based on the known technical information. Pure fission solutions are based largely on existing both fusion and nuclear technology, thereby prohibiting a fair side-by-side comparison

  19. Design and Preparation of RF System for the Lower Hybrid Fast Wave Heating and Current Drive Research on VEST

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Ho; Jeong, Seung Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, Hyun Woo; Lee, Byung Je [Kwang Woon University, Chuncheon (Korea, Republic of); Jo, Jong Gab; Lee, Hyun Young; Hwang, Yong Seok [Seoul National University, Seoul (Korea, Republic of)

    2015-10-15

    Continuous current drive is one of the key issues for tokamak to be a commercial fusion reactor. As a part of new and efficient current drive concept research by using a Lower Hybrid Fast Wave (LHFW), the experimental study is planned on Versatile Experiment Spherical Torus (VEST) and a RF system is being developed in collaboration with Kwang Woon University (KWU), Korea Accelerator Plasma Research Association (KAPRA) and Seoul National University (SNU). The LHFW RF system includes UHF band klystron, inter-digital antenna, RF diagnostics and power transmission sub components such as circulator, DC breaker, vacuum feed-thru. The design and preparation status of the RF system will be presented in the meeting in detail. A RF system has been designed and prepared for the experimental study of efficient current drive by using Lower Hybrid Fast Wave. Overall LHFW RF system including diagnostics is designed to deliver about 10 kW in UHF band. And the key hardware components including klystron and antenna are being prepared and designed through the collaboration with KWU, KAPRA and SNU.

  20. Research on consistency measurement and weight estimation approach of hybrid uncertain comparison matrix

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The consistency measurement and weight estimation approach of the hybrid uncertain comparison matrix in the analytic hierarchy process (AHP) are studied. First, the decision-making satisfaction membership function is defined based on the decision making's allowable error. Then, the weight model based on the maximal satisfactory consistency idea is suggested, and the consistency index is put forward. Moreover, the weight distributing value model is developed to solve the decision making misleading problem since the multioptimization solutions in the former model. Finally, the weights are ranked based on the possibility degree approach to obtain the ultimate order.

  1. High Efficiency and Long Life Hybrid Photovoltaic Research for Space Applications

    Science.gov (United States)

    2007-07-05

    fabrication, a thin active layer is deposited onto ZnO nanorods by using spin coating . The thin active layer was used as hole transporting and light...absorbing material. The device was then fabricated by spin - coating a layer of PEDOT:PSS with an effective thickness of 50 nm before thermal...P3HT) and Sample C (ZnO/P3HT:TiO2) represent the composites by spin coating neat P3HT and P3HT:TiO2 nanorods hybrid thin active layers onto the

  2. Gender determination of avian embryo

    Science.gov (United States)

    Daum, Keith A.; Atkinson, David A.

    2002-01-01

    Disclosed is a method for gender determination of avian embryos. During the embryo incubation process, the outer hard shells of eggs are drilled and samples of allantoic fluid are removed. The allantoic fluids are directly introduced into an ion mobility spectrometer (IMS) for analysis. The resulting spectra contain the relevant marker peaks in the positive or negative mode which correlate with unique mobilities which are sex-specific. This way, the gender of the embryo can be determined.

  3. Intraply Hybrid Composite Design

    Science.gov (United States)

    Chamis, C. C.; Sinclair, J. H.

    1986-01-01

    Several theoretical approaches combined in program. Intraply hybrid composites investigated theoretically and experimentally at Lewis Research Center. Theories developed during investigations and corroborated by attendant experiments used to develop computer program identified as INHYD (Intraply Hybrid Composite Design). INHYD includes several composites micromechanics theories, intraply hybrid composite theories, and integrated hygrothermomechanical theory. Equations from theories used by program as appropriate for user's specific applications.

  4. Frequency of chromosomal aneuploidy in high quality embryos from young couples using preimplantation genetic screening

    Directory of Open Access Journals (Sweden)

    Farzaneh Fesahat

    2017-09-01

    Full Text Available Background: Selection of the best embryo for transfer is very important in assisted reproductive technology (ART. Using morphological assessment for this selection demonstrated that the correlation between embryo morphology and implantation potential is relatively weak. On the other hand, aneuploidy is a key genetic factor that can influence human reproductive success in ART. Objective: The aim of this lab trial study was to evaluate the incidence of aneuploidies in five chromosomes in the morphologically high-quality embryos from young patients undergoing ART for sex selection. Materials and Methods: A total of 97 high quality embryos from 23 women at the age of 37or younger years that had previously undergone preimplantation genetic screening for sex selection were included in this study. After washing, the slides of blastomeres from embryos of patients were reanalyzed by fluorescence in-situ hybridization for chromosomes 13, 18 and 21. Results: There was a significant rate of aneuploidy determination in the embryos using preimplantation genetic screening for both sex and three evaluated autosomal chromosomes compared to preimplantation genetic screening for only sex chromosomes (62.9% vs. 24.7%, p=0.000. The most frequent detected chromosomal aneuploidy was trisomy or monosomy of chromosome 13. Conclusion: There is considerable numbers of chromosomal abnormalities in embryos generated in vitro which cause in vitro fertilization failure and it seems that morphological characterization of embryos is not a suitable method for choosing the embryos without these abnormalities

  5. Who abandons embryos after IVF?

    LENUS (Irish Health Repository)

    Walsh, A P H

    2010-04-01

    This investigation describes features of in vitro fertilisation (IVF) patients who never returned to claim their embryos following cryopreservation. Frozen embryo data were reviewed to establish communication patterns between patient and clinic; embryos were considered abandoned when 1) an IVF patient with frozen embryo\\/s stored at our facility failed to make contact with our clinic for > 2 yrs and 2) the patient could not be located after a multi-modal outreach effort was undertaken. For these patients, telephone numbers had been disconnected and no forwarding address was available. Patient, spouse and emergency family contact\\/s all escaped detection efforts despite an exhaustive public database search including death records and Internet directory portals. From 3244 IVF cycles completed from 2000 to 2008, > or = 1 embryo was frozen in 1159 cases (35.7%). Those without correspondence for > 2 yrs accounted for 292 (25.2%) patients with frozen embryos; 281 were contacted by methods including registered (signature involving abandoned embryos did not differ substantially from other patients. The goal of having a baby was achieved by 10\\/11 patients either by spontaneous conception, adoption or IVF. One patient moved away with conception status unconfirmed. The overall rate of embryo abandonment was 11\\/1159 (< 1%) in this IVF population. Pre-IVF counselling minimises, but does not totally eliminate, the problem of abandoned embryos. As the number of abandoned embryos from IVF accumulates, their fate urgently requires clarification. We propose that clinicians develop a policy consistent with relevant Irish Constitutional provisions to address this medical dilemma.

  6. Research Update: Relativistic origin of slow electron-hole recombination in hybrid halide perovskite solar cells

    Science.gov (United States)

    Azarhoosh, Pooya; McKechnie, Scott; Frost, Jarvist M.; Walsh, Aron; van Schilfgaarde, Mark

    2016-09-01

    The hybrid perovskite CH3NH3PbI3 (MAPI) exhibits long minority-carrier lifetimes and diffusion lengths. We show that slow recombination originates from a spin-split indirect-gap. Large internal electric fields act on spin-orbit-coupled band extrema, shifting band-edges to inequivalent wavevectors, making the fundamental gap indirect. From a description of photoluminescence within the quasiparticle self-consistent GW approximation for MAPI, CdTe, and GaAs, we predict carrier lifetime as a function of light intensity and temperature. At operating conditions we find radiative recombination in MAPI is reduced by a factor of more than 350 compared to direct gap behavior. The indirect gap is retained with dynamic disorder.

  7. Research on Hybrid Power System with Dual Stator-winding and Its Decoupled Control Strategy

    Institute of Scientific and Technical Information of China (English)

    WEI Shu-guang; MA Xiao-jun; KE Rong-shuo; LIU Qiu-li

    2012-01-01

    For the bi-power system adopted widely in future armored vehicles,a hybrid power generator with dual stator-winding was proposed.Its structure and working principle were analyzed first,and its main parameters were determined and verified according to the power requirements.The system's mathematical model was established,and a decoupled control method was put forward on the basis of the instantaneous reactive power theory.For the voltage building-up,a voltage control strategy was designed on the basis of mixed reactive power compensation to implement stabilized 28V and 270V outputs simultaneously.The simulation results show that the stabilization accuracy and disturbance rejection ability of the system are improved much more than other ordinary generators.

  8. Research Update: Relativistic origin of slow electron-hole recombination in hybrid halide perovskite solar cells

    Directory of Open Access Journals (Sweden)

    Pooya Azarhoosh

    2016-09-01

    Full Text Available The hybrid perovskite CH3NH3PbI3 (MAPI exhibits long minority-carrier lifetimes and diffusion lengths. We show that slow recombination originates from a spin-split indirect-gap. Large internal electric fields act on spin-orbit-coupled band extrema, shifting band-edges to inequivalent wavevectors, making the fundamental gap indirect. From a description of photoluminescence within the quasiparticle self-consistent GW approximation for MAPI, CdTe, and GaAs, we predict carrier lifetime as a function of light intensity and temperature. At operating conditions we find radiative recombination in MAPI is reduced by a factor of more than 350 compared to direct gap behavior. The indirect gap is retained with dynamic disorder.

  9. Research and practice of designing hydro/photovoltaic hybrid power system in microgrid

    Institute of Scientific and Technical Information of China (English)

    Wang Yibo; Xu Honghua

    2013-01-01

    Small-hydro power station is often used in remote areas beside a river,but it doesn't match electricity demand so well,especially in dry seasons.A photovoltaic (PV) system with battery is a suitable option to complement the electricity gap.In this paper,a new structure of megawatt-class PV system integrating battery at DC-bus (DC:direct current) is proposed to be used in hydro/PV hybrid power system,and 4 main designing considerations and several key equipments are discussed.In 2011,a 2 MWp PV station with the proposed structure was built up in Yushu,China.From stability analysis,the station shows a strong stability under load cut-in/off and solar irradiance' s fluctuation.

  10. Research on the adaptive hybrid search tree anti-collision algorithm in RFID system

    Institute of Scientific and Technical Information of China (English)

    靳晓芳

    2016-01-01

    Due to more tag-collisions result in failed transmissions, tag anti-collision is a very vital issue in the radio frequency identification ( RFID) system.However, so far decreases in communication time and increases in throughput are very limited.In order to solve these problems, this paper presents a novel tag anti-collision scheme, namely adaptive hybrid search tree ( AHST) , by combining two al-gorithms of the adaptive binary-tree disassembly ( ABD) and the combination query tree ( CQT) , in which ABD has superior tag identification velocity and CQT has optimum performance in system throughput and search timeslots.From the theoretical analysis and numerical simulations, the pro-posed algorithm can colligate the advantages of above algorithms, improve the system throughput and reduce the searching timeslots dramatically.

  11. Neutron transport-burnup code MCORGS and its application in fusion fission hybrid blanket conceptual research

    Science.gov (United States)

    Shi, Xue-Ming; Peng, Xian-Jue

    2016-09-01

    Fusion science and technology has made progress in the last decades. However, commercialization of fusion reactors still faces challenges relating to higher fusion energy gain, irradiation-resistant material, and tritium self-sufficiency. Fusion Fission Hybrid Reactors (FFHR) can be introduced to accelerate the early application of fusion energy. Traditionally, FFHRs have been classified as either breeders or transmuters. Both need partition of plutonium from spent fuel, which will pose nuclear proliferation risks. A conceptual design of a Fusion Fission Hybrid Reactor for Energy (FFHR-E), which can make full use of natural uranium with lower nuclear proliferation risk, is presented. The fusion core parameters are similar to those of the International Thermonuclear Experimental Reactor. An alloy of natural uranium and zirconium is adopted in the fission blanket, which is cooled by light water. In order to model blanket burnup problems, a linkage code MCORGS, which couples MCNP4B and ORIGEN-S, is developed and validated through several typical benchmarks. The average blanket energy Multiplication and Tritium Breeding Ratio can be maintained at 10 and 1.15 respectively over tens of years of continuous irradiation. If simple reprocessing without separation of plutonium from uranium is adopted every few years, FFHR-E can achieve better neutronic performance. MCORGS has also been used to analyze the ultra-deep burnup model of Laser Inertial Confinement Fusion Fission Energy (LIFE) from LLNL, and a new blanket design that uses Pb instead of Be as the neutron multiplier is proposed. In addition, MCORGS has been used to simulate the fluid transmuter model of the In-Zinerater from Sandia. A brief comparison of LIFE, In-Zinerater, and FFHR-E will be given.

  12. Clinical doubt on embryo implantation%胚胎植入的临床疑惑

    Institute of Scientific and Technical Information of China (English)

    庄广伦

    2013-01-01

    Comparing to the research on potential development of oocyte and embryo,endometrium receptivity is less and slowly understood,because there is no good implantation research model in human. The paper discusses the following questions in clinical embryo implantation: the clinical accident ectopic pregnancy,the importance of decidualization, the proper location of embryo invasion, and the effect of curettage of endometrium on implantation.

  13. Self-correction in human embryos%胚胎自我修复

    Institute of Scientific and Technical Information of China (English)

    徐艳文

    2013-01-01

    Reanalysis of aneuploid embryos diagnosed by preimplantation genetic screening (PGS) using fluorescence in situ hybridization(FISH) showed that part or all cells in some human cleavage-stage embryos may undergo self-correction during preimplantation development. Putative embryo self-correction mechanisms include embryonic mosaicism, preferential segregation of chromosomal abnormalities to the trophectoderm and extrusion or duplication of aneuploid chromosomes resulting in uniparental disomy. However, embryo self-correction has not been proved in the study using a single nucleotide polymorphism (SNP)microarray-based 24 chromosome aneuploidy screening technology. Neither preferential segregation of aneuploidy to trophectoderm nor uniparental disomy was found. Further study to improve the accuracy of karyotyping on cleavage-stage embryos is definitely needed.

  14. Research Progress of Galectin-3,Bcl-2 and Embryo Development Termination%Galectin-3和Bcl-2与胚胎停育研究进展

    Institute of Scientific and Technical Information of China (English)

    徐耀辉

    2012-01-01

    Galectin-3 is a member of galectin family,which interacts with intracellular glycoprotein,cell surface molecules and extracellular matrix proteins by its carbohydrate recognition domains, participates the progress of embryo implantation,embryogenesis and placenta formation,and establishes and maintains a close relationship with pregnancy. Inhibitors of apoptosis protein Bcl-2 and Galectin-3 have significant sequence similarity,and may have the same apoptosis pathway,which participates in the growth and differentiation of villous trophoblast cells in people's earlier pregnancy and the process of decidualization of endometrium,in addition,playing a critical role in the villous production,growth,placenta formation and in its tissue structure rebuilding and functional perfection.%Galectin-3 是半乳糖凝集素家族中的一员,能通过其糖识别域与细胞内糖蛋白、细胞表面分子和细胞外基质蛋白相互作用,参与胚胎着床、胚胎发生和胎盘形成等过程,与妊娠成功建立和维持密切相关.凋亡抑制蛋白Bcl-2与Galectin-3有明显的序列相似性,可能存在共同细胞凋亡通路,在人早孕过程中参与了绒毛滋养层细胞的增殖和分化、子宫内膜蜕膜化的过程,在绒毛的发生、发育、胎盘形成和组织结构改建及功能完善等方面发挥着重要作用.

  15. Aneuploidy analysis of non-pronuclear embryos from IVF with use of array CGH: a case report.

    Science.gov (United States)

    Lixin, Deng; Zhifeng, Xiang; Cong, He; Jinzhou, Zhang; Hongbin, Xie

    2014-06-01

    By using array comparative genomic hybridization (array CGH), to analyze the aneuploidy of the single blastomeres from non-pronuclear embryos on cleavage-stage in IVF cycle. Four non-pronuclear embryos were got from an IVF cycle, and the each single cell was biopsied from the four cleavage-stage embryos on the third day after the insemination which was investigated by using array CGH. After the biopsy, all the embryos continued to cleave, and lately entered the morula stage on the fifth day, just one embryo 3 was developed to early blastocyst stage on the sixth day. The four blastomere 24 chromosomes showed one X monomer and three normal XY diploids; the autosome chromosomes of blastomeres were abnormally gained or lost at different chromosome from four embryos, such as Embryo 1 : 49,X (-1, -5, -11, -19, -20, -21, -Y, +3, +6, +7, +8, +10, +13, +14, +16, +17, +18); Embryo 2 : 44,XY (-12, -15); Embryo 3: 47,XY (-3, -8, -9, -21, +7, +17, +18, +19, +20); Embryo 4 : 54,XY (+4, +7, +10, +12, +13, +16, +17, +22). With the use of the array CGH, the aneuploidy analysis could review the abnormal chromosomes of single blastomere from the non-pronuclear embryos, which can harbor the risk of abnormal sex chromosome and autosome chromosomes.

  16. Enhancement of NMRI Mouse Embryo Development In vitro

    Directory of Open Access Journals (Sweden)

    Abedini, F.

    2013-12-01

    Full Text Available Most of the systematic studies used in the development of human embryo culture media have been done first on mouse embryos. The general use of NMRI outbred mice is a model for toxicology, teratology and pharmacology. NMRI mouse embryo exhibit the two-cell block in vitro. The objective of this study was to evaluate and compare the effects of four kinds of culture media on the development of zygotes (NMRI after embryo vitrification. One-cell mouse embryos were obtained from NMRI mice after superovulation and mating with adult male NMRI mice. And then randomly divided into 4 groups for culture in four different cultures media including: M16 (A, DMEM/Ham, F-12 (B, DMEM/Ham's F-12 co-culture with Vero cells(C and DMEM/Ham's F-12 co-culture with MEF cells (D. Afterward all of the embryos were vitrified in EFS40 solution and collected. Results of our study revealed, more blastocysts significantly were developed with co-culture with MEF cells in DMEM/Ham's F-12 medium. More research needed to understand the effect of other components of culture medium, and co-culture on NMRI embryo development.

  17. Shaping the norms that regulate international commerce of embryos.

    Science.gov (United States)

    Gard, Julie A; Stringfellow, David A

    2014-01-01

    As various embryo technologies in livestock were developed and evolved to a state of usefulness over the past 40 years, scientists with a specific interest in infectious diseases sought to determine the epidemiologic consequences of movement, especially international movement, of increasing numbers of embryos. Many of the foundational studies in this area were reported in Theriogenology, beginning in the 1970s and especially throughout the 1980s and 1990s. Unquestionably, Theriogenology has been a widely used venue for dissemination of basic information on this subject, which ultimately led to the development of the now universally accepted techniques for certification of embryo health. Today it is well-recognized that movement in commerce of embryos, especially in vivo-derived embryos, is a very low-risk method for exchange of animal germ plasm. This paper chronicles the evolution of strategies for health certification of embryos. An overview is provided of the calculated efforts of practitioners, scientists, and regulators to organize, forge necessary partnerships, stimulate needed research, provide purposeful analysis of the results, and, through these processes, guarantee the universal acceptance of efficient protocols for certifying the health of embryos intended for movement in international commerce.

  18. Blastocyst Morphology Holds Clues Concerning The Chromosomal Status of The Embryo

    Directory of Open Access Journals (Sweden)

    Rita de Cassia Savio Figueira

    2015-07-01

    Full Text Available Background: Embryo morphology has been proposed as an alternative marker of chromosomal status. The objective of this retrospective cohort study was to investigate the association between the chromosomal status on day 3 of embryo development and blastocyst morphology. Materials and Methods: A total of 596 embryos obtained from 106 cycles of intracytoplasmic sperm injection (ICSI followed by preimplantation genetic aneuploidy screening (PGS were included in this retrospective study. We evaluated the relationship between blastocyst morphological features and embryonic chromosomal alteration. Results: Of the 564 embryos with fluorescent in situ hybridization (FISH results, 200 reached the blastocyst stage on day 5 of development. There was a significantly higher proportion of euploid embryos in those that achieved the blastocyst stage (59.0% compared to embryos that did not develop to blastocysts (41.2% on day 5 (P<0.001. Regarding blastocyst morphology, we observed that all embryos that had an abnormal inner cell mass (ICM were aneuploid. Embryos with morphologically normal ICM had a significantly higher euploidy rate (62.1%, P<0.001. As regards to the trophectoderm (TE morphology, an increased rate of euploidy was observed in embryos that had normal TE (65.8% compared to embryos with abnormal TE (37.5%, P<0.001. Finally, we observed a two-fold increase in the euploidy rate in high-quality blastocysts with both high-quality ICM and TE (70.4% compared to that found in low-quality blastocysts (31.0%, P<0.001. Conclusion: Chromosomal abnormalities do not impair embryo development as aneuploidy is frequently observed in embryos that reach the blastocyst stage. A high-quality blastocyst does not represent euploidy of chromosomes 13, 14, 15, 16, 18, 21, 22, X and Y. However, aneuploidy is associated with abnormalities in the ICM morphology. Further studies are necessary to confirm whether or not the transfer of blastocysts with low-quality ICM should be

  19. 人早期胚胎解冻后氨基酸代谢变化的研究%Research on amino acid metabolism of human early embryo after frozen-thawed

    Institute of Scientific and Technical Information of China (English)

    唐杰; 方丛; 李婷婷; 张敏芳; 梁晓燕

    2011-01-01

    Objective: To study the amino acid metabolism of human early frozen-thawed embryo.Methods: Eighteen spare human embryos obtained from 13 patients undergoing in vitro ferbilization (IVF) were researched.Spare human embryos on day 3 of development were cultured individually in 20 μl drops of pre-equilibrated blastocyst culture medium for 2 hours before vitrification.Embryo-free drops were incubated in the same dish as the controls.The remaining 15 μl mediums from the drops were collected before freezing, 1/2,1,2,4,6 and 24 hours after thawing, and were analyzed for 20 free amino acids level by high performance liquid chromatography ( HPLC).Results: The levels of glutamine, histidine, tryptophan and lysine in blank controls were different among different time points.However, they were not increased or decreased gradually.The concentrations of other 16 amino acids remained same at different time points.One hour after thawing, concentrations of 20 free amino acids were all increased comparing with the blank control at same time point; the amino acid appearance and turnover was significant higher than that pre-freezing ( P < 0.05).The amino acid appearance had no significant difference betweem 2, 6 or 24 hours after thawing and pre-freezing ( P > 0.05).The amino acid depletion pre-freezing was significant lower than that 1/2, 4, 6 and 24 hours after thawing (P <0.05).The amino acid appearance 1/2 and 4 hours after thawing was significant lower than that pre-freezing ( P < 0.05).There was no significant difference in amino acid turnover between 1/2,4 hours after thawing and pre-freezing (P > 0.05).The amino acid turnover 24 hours after thawing was significant higher than that pre-freezing (P < 0.05).The amino acid turnover 1/2,4 and 6 hours after thawing were significant lower than that 1 hour after thawing (P <0.05).Conclusion: Human early embryo begins amino acid metabolism and recovers from metabolism stasis 1/2 hour after embryo thawing , and the amino

  20. Regulation of somatic embryo development in Norway spruce (Picea abies). A molecular approach to the characterization of specific developmental stages

    Energy Technology Data Exchange (ETDEWEB)

    Sabala, I. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Genetics

    1998-12-31

    Embryo development is a complex process involving a set of strictly regulated events. The regulation of these events is poorly understood especially during the early stages of embryo development. Somatic embryos go through the same developmental stages as zygotic embryos making them an ideal model system for studying the regulation of embryo development. We have used embryogenic cultures of Picea abies to study some aspects of the regulation of embryo development in gymnosperms. The bottle neck during somatic embryogenesis is the switch from the proliferation stage to the maturation stage. This switch is initiated by giving somatic embryos a maturation treatment i.e. the embryos are treated with abscisic acid (ABA). Somatic embryos which respond to ABA by forming mature somatic embryos were stimulated to secret a 70 kDa protein, AF70. The af70 gene was isolated and characterised. The expression of the af70 gene was constitutive in embryos but was highly ABA-induced in seedlings. Moreover, expression of this gene was stimulated during cold acclimation of Picea abies seedlings. A full length Picea abies cDNA clone Pa18, encoding a protein with the characteristics of plant lipid transfer proteins (LTPs), was isolated and characterised. The Pa18 gene is constitutively expressed in embryogenic cultures of Picea abies representing different stages of development as well as in nonembryogenic callus and seedlings. In situ hybridization showed that Pa18 gene is expressed in all embryonic cells of proliferating somatic embryos but the expression of the gene in mature somatic and zygotic embryos is restricted to the outer cell layer. Southern blot analysis at different stringencies was consistent with a single gene. An alteration in expression of Pa18 causes disturbance in the formation of the proper outer cell layer in the maturing somatic embryos. In addition to its influence on embryo development the Pa18 gene product also inhibits growth of Agrobacterium tumefaciens 195

  1. Hybrid FOSS Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Armstrong researchers are continuing their efforts to further develop FOSS technologies. A hybrid FOSS technique (HyFOSS) employs conventional continuous grating...

  2. TNF-alpha expression in embryos exposed to a teratogen.

    Science.gov (United States)

    Ivnitsky, I; Torchinsky, A; Gorivodsky, M; Zemliak, I; Orenstein, H; Savion, S; Shepshelovich, J; Carp, H; Fein, A; Toder, V

    1998-12-01

    The role of tumor necrosis factor (TNF)-alpha produced by embryonic cells in normal and abnormal development is poorly understood. To assess to what extent TNF-alpha may be involved in the process of induced dysmorphogenesis, the expression of TNF-alpha and TNF-alpha receptor (TNFRI) mRNA as well as TNF-alpha protein was evaluated in embryos responding to a cyclophosphamide (CP)-induced teratogenic insult. The effect of maternal immunostimulation increasing the embryo's tolerance to CP on TNF-alpha expression was also investigated. ICR female mice were treated intraperitoneally with 40 mg/kg CP on day 12 of pregnancy. The immunostimulator, xenogeneic rat splenocytes, was injected intrauterine 21 days before mating. Embryos were collected on days 13, 14, or 15 of pregnancy. TNF-alpha mRNA, TNFRI mRNA, and TNF-alpha protein expression were evaluated by in situ hybridization and immunostaining techniques in control, teratogen-treated, and immuno-stimulated teratogen-treated embryos. CP-treated embryos showed severe external brain and craniofacial anomalies already visible on day 14 of pregnancy. TNF-alpha mRNA transcripts were detected in cells of the brain and the head of 13-day embryos, which preceded the occurrence of CP-induced external craniofacial anomalies. On day 15 of pregnancy, when severe craniofacial anomalies increased, a significant increase in the intensity of TNF-alpha, TNFR1 mRNA transcripts, and TNF-alpha protein expression were observed in cells of the malformed regions of the head and the brain. In other nonmalformed organs of CP-treated embryos such as the liver (not macroscopically different from controls), neither TNF-alpha nor TNFR1 transcripts were detected. Immunostimulation substantially diminished the severity of CP-induced brain and craniofacial anomalies, decreased the resorption rate, and was associated with decreased intensity of TNF-alpha mRNA transcripts detected on day 15 of pregnancy in the head and the brain of CP-treated embryos

  3. Hybrid Connections: An Immigrant Researcher Maneuvering' Access to a Refugee Community

    Directory of Open Access Journals (Sweden)

    Eleni Oikonomidoy

    2009-03-01

    Full Text Available Reflecting on the journey of a novice immigrant researcher trying to negotiate access to members of a refugee community, this essay proposes the undeniable value of exploratory stages in cross-cultural research. Drawing insights from the researcher's field notes, it describes snapshots of the multiple ethical and practical dilemmas, which shaped the route of the researcher's journey. It proposes that interactions in extra-research spaces provide fertile ground for identification through flexible forms of belonging, which in turn endorse intercultural understanding. Nonetheless, nothing is decisive. The novice international cross-cultural researcher juggles continually between the roles of a pirate and a fellow traveler. URN: urn:nbn:de:0114-fqs090277

  4. 混合驱动机构研究进展与发展趋势%Research Progress and Development Trend of Hybrid-driven Mechanism

    Institute of Scientific and Technical Information of China (English)

    李瑞琴; 王英; 王明亚; 赵耀虹; 宋杰

    2016-01-01

    混合驱动机构是可控机构的一种,其适度柔性以及降低驱动与控制成本的特性与优势使其成为现代机构学的重要研究分支之一。随着对混合驱动机构研究的深入,混合驱动机构理论和应用也不断地发展和创新。对现有的研究成果加以分析和总结将有利于促进混合驱动机构理论和应用的进一步发展。分析混合驱动机构的内涵,分别论述双自由度和多自由度混合驱动机构的研究进展,主要包括:混合驱动机构的构型设计与可动性、混合驱动机构的轨迹特征、混合驱动机构的运动学、混合驱动机构的动力学及混合驱动机构的应用等方面的研究进展。提出混合驱动机构研究的关键问题,总结了混合驱动机构的未来发展趋势。研究成果对拓展混合驱动机构的设计空间、开辟混合驱动机构新的应用领域具有重要意义。%Hybrid-driven mechanism is one kind of controllable mechanism. The characteristics and advantages of moderate flexibility and reducing the cost of driving and controlling of hybrid-driven mechanism make it become one of the important branches of modern mechanisms. The theory and application of hybrid-driven mechanism are constantly developing and innovating along with the further research of hybrid driving mechanism. Analyzing and summarizing the existing research results will be beneficial to promote the further development of the theory and application of hybrid-driven mechanism. The connotation of hybrid-driven mechanism is analyzed. The research progress of two-DOF and multi-DOF hybrid-driven mechanism is discussed, respectively. The main contents are follows: type synthesis and mobility of hybrid-driven mechanism, trajectory characteristics of hybrid-driven mechanism, kinematics and dynamics of hybrid-driven mechanism, applications of hybrid-driven mechanism, etc. The key issues of in the research of hybrid-driven mechanism are

  5. Study on the in vitro culture of cut plants in wheat haploid embryo induction by a wheat × maize cross

    Institute of Scientific and Technical Information of China (English)

    Jian GU; Kun LIU; Shaoxiang LI; Yuxian TIAN; Hexian YANG; Mujun YANG

    2008-01-01

    The wheat × maize system is one of the most effective ways to produce haploids in wheat. Whether and how it could be successfully applied in practical breeding mostly depends upon the efficiency of haploid embryo pro-duction. To perfect the protocols of haploid embryo induc-tion, the efficiency of haploid embryo production between in vitro culture of cut plant and intact plant growth for hybrid spikes with two F1 wheat hybrids and two maize varieties was compared. Effects of different cutting plant times and formulas of nutrient solutions for cut plant cul-ture on haploid embryo formation were also studied. Results indicated that the embryo rate of in vitro culture was 3.29 times that of intact plant growth, with the figures of 31.6% vs 9.6%, respectively. The optimal time for cut plant culture was 24 h after pollination. Formulas of nutri-ent solutions significantly affected the efficiency of haploid embryo induction. With an embryo rate of 0-35.5%, add-could raise the caryopsis and embryo rates. According to this study, the best medium for cut plant culture was: phate, with which a caryopsis rate of 95% and an embryo rate of about 30% could be obtained.

  6. Influence of embryo handling and transfer method on pig cloning efficiency.

    Science.gov (United States)

    Shi, Junsong; Zhou, Rong; Luo, Lvhua; Mai, Ranbiao; Zeng, Haiyu; He, Xiaoyan; Liu, Dewu; Zeng, Fang; Cai, Gengyuan; Ji, Hongmei; Tang, Fei; Wang, Qinglai; Wu, Zhenfang; Li, Zicong

    2015-03-01

    The somatic cell nuclear transfer (SCNT) technique could be used to produce genetically superior or genetically engineered cloned pigs that have wide application in agriculture and bioscience research. However, the efficiency of porcine SCNT currently is very low. Embryo transfer (ET) is a key step for the success of SCNT. In this study, the effects of several ET-related factors, including cloned embryo culture time, recipient's ovulation status, co-transferred helper embryos and ET position, on the success rate of pig cloning were investigated. The results indicated that transfer of cloned embryos cultured for a longer time (22-24h vs. 4-6h) into pre-ovulatory sows decreased recipient's pregnancy rate and farrowing rate, and use of pre-ovulatory and post-ovulatory sows as recipients for SCNT embryos cultured for 22-24h resulted in a similar porcine SCNT efficiency. Use of insemination-produced in vivo fertilized, parthenogenetically activated and in vitro fertilized embryos as helper embryos to establish and/or maintain pregnancy of SCNT embryos recipients could not improve the success rate of porcine SCNT. Transfer of cloned embryos into double oviducts of surrogates significantly increased pregnancy rate as well as farrowing rate of recipients, and the developmental rate of transferred cloned embryos, as compared to unilateral oviduct transfer. This study provided useful information for optimization of the embryo handling and transfer protocol, which will help to improve the ability to generate cloned pigs.

  7. Industrial and Academic Collaboration: Hybrid Models for Research and Innovation Diffusion

    Science.gov (United States)

    de Freitas, Sara; Mayer, Igor; Arnab, Sylvester; Marshall, Ian

    2014-01-01

    This paper explores how, in the light of global economic downturn and rising student populations, new academic-industrial models for research collaboration based upon specific technological expertise and knowledge can be developed as potential mechanisms for preserving and extending central university research infrastructure. The paper explores…

  8. Industrial and Academic Collaboration: Hybrid Models for Research and Innovation Diffusion

    Science.gov (United States)

    de Freitas, Sara; Mayer, Igor; Arnab, Sylvester; Marshall, Ian

    2014-01-01

    This paper explores how, in the light of global economic downturn and rising student populations, new academic-industrial models for research collaboration based upon specific technological expertise and knowledge can be developed as potential mechanisms for preserving and extending central university research infrastructure. The paper explores…

  9. Research of hail impact on aircraft wheel door with lattice hybrid structure

    Science.gov (United States)

    Li, Shengze; Jin, Feng; Zhang, Weihua; Meng, Xuanzhu

    2016-09-01

    Aimed at a long lasting issue of hail impact on aircraft structures and aviation safety due to its high speed, the resistance performance of hail impact on the wheel door of aircraft with lattice hybrid structure is investigated. The proper anti-hail structure can be designed both efficiency and precision based on this work. The dynamic responses of 8 different sandwich plates in diverse impact speed are measured. Smoothed Particle Hydrodynamic (SPH) method is introduced to mimic the speciality of solid-liquid mixture trait of hailstone during the impact process. The deformation and damage degree of upper and lower panel of sandwich plate are analysed. The application range and failure mode for the relevant structure, as well as the energy absorbing ratio between lattice structure and aluminium foam are summarized. Results show that the tetrahedral sandwich plate with aluminium foam core is confirmed the best for absorbing energy. Furthermore, the high absorption characteristics of foam material enhance the capability of the impact resistance for the composition with lattice structure without increasing the structure surface density. The results of study are of worth to provide a reliable basis for reduced weight aircraft wheel door.

  10. Research of Ant Colony Optimized Adaptive Control Strategy for Hybrid Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Linhui Li

    2014-01-01

    Full Text Available Energy management control strategy of hybrid electric vehicle has a great influence on the vehicle fuel consumption with electric motors adding to the traditional vehicle power system. As vehicle real driving cycles seem to be uncertain, the dynamic driving cycles will have an impact on control strategy’s energy-saving effect. In order to better adapt the dynamic driving cycles, control strategy should have the ability to recognize the real-time driving cycle and adaptively adjust to the corresponding off-line optimal control parameters. In this paper, four types of representative driving cycles are constructed based on the actual vehicle operating data, and a fuzzy driving cycle recognition algorithm is proposed for online recognizing the type of actual driving cycle. Then, based on the equivalent fuel consumption minimization strategy, an ant colony optimization algorithm is utilized to search the optimal control parameters “charge and discharge equivalent factors” for each type of representative driving cycle. At last, the simulation experiments are conducted to verify the accuracy of the proposed fuzzy recognition algorithm and the validity of the designed control strategy optimization method.

  11. The Hybrid KICA-GDA-LSSVM Method Research on Rolling Bearing Fault Feature Extraction and Classification

    Directory of Open Access Journals (Sweden)

    Jiyong Li

    2015-01-01

    Full Text Available Rolling element bearings are widely used in high-speed rotating machinery; thus proper monitoring and fault diagnosis procedure to avoid major machine failures is necessary. As feature extraction and classification based on vibration signals are important in condition monitoring technique, and superfluous features may degrade the classification performance, it is needed to extract independent features, so LSSVM (least square support vector machine based on hybrid KICA-GDA (kernel independent component analysis-generalized discriminate analysis is presented in this study. A new method named sensitive subband feature set design (SSFD based on wavelet packet is also presented; using proposed variance differential spectrum method, the sensitive subbands are selected. Firstly, independent features are obtained by KICA; the feature redundancy is reduced. Secondly, feature dimension is reduced by GDA. Finally, the projected feature is classified by LSSVM. The whole paper aims to classify the feature vectors extracted from the time series and magnitude of spectral analysis and to discriminate the state of the rolling element bearings by virtue of multiclass LSSVM. Experimental results from two different fault-seeded bearing tests show good performance of the proposed method.

  12. Research on Hybrid Seismic Response Control System for Motion Control of Two Span Bridge

    Science.gov (United States)

    Heo, G.; Kim, C.; Jeon, S.; Seo, S.; Jeon, J.

    2016-09-01

    In this paper, a hybrid seismic response control (HSRC) system was developed to control bridge motion caused by seismic load. It was aimed at optimum vibration control, composed of a rubber bearing of passive type and a MR-damper of semi-active type. The bridge model was built for experiment, a two-span bridge of 8.3 meters in length with the HSRC system put up on it. Then, inflicting El-centro seismic load on it, shaking table tests were carried out to confirm the system's validity. The experiments were conducted under the basic structure state (without an MR-damper applied) first, and then under the state with an MR-damper applied. It was also done under the basic structure state with a reinforced rubber bearing applied, then the passive on/off state of the HSRC system, and finally the semi-active state where the control algorithm was applied to the system. From the experiments, it was observed that collision rather increased when the MR-damper alone was applied, and also that the application of the HSRC system effectively prevented it from occurring. As a result, the HSRC system was proven to be effective in mitigating responses of the two-span bridge under seismic load.

  13. Oviduct: roles in fertilization and early embryo development.

    Science.gov (United States)

    Li, Shuai; Winuthayanon, Wipawee

    2017-01-01

    Animal oviducts and human Fallopian tubes are a part of the female reproductive tract that hosts fertilization and pre-implantation development of the embryo. With an increasing understanding of roles of the oviduct at the cellular and molecular levels, current research signifies the importance of the oviduct on naturally conceived fertilization and pre-implantation embryo development. This review highlights the physiological conditions within the oviduct during fertilization, environmental regulation, oviductal fluid composition and its role in protecting embryos and supplying nutrients. Finally, the review compares different aspects of naturally occurring fertilization and assisted reproductive technology (ART)-achieved fertilization and embryo development, giving insight into potential areas for improvement in this technology. © 2017 Society for Endocrinology.

  14. Human embryo cloning prohibited in Hong Kong.

    Science.gov (United States)

    Liu, Athena

    2005-12-01

    Since the birth of Dolly (the cloned sheep) in 1997, debates have arisen on the ethical and legal questions of cloning-for-biomedical-research (more commonly termed "therapeutic cloning") and of reproductive cloning using human gametes. Hong Kong enacted the Human Reproductive Technology Ordinance (Cap 561) in 2000. Section 15(1)(e) of this Ordinance prohibits the "replacing of the nucleus of a cell of an embryo with a nucleus taken from any other cell," i.e., nucleus substitution. Section 15(1)(f) prohibits the cloning of any embryo. The scope of the latter, therefore, is arguably the widest, prohibiting all cloning techniques such as cell nucleus replacement, embryo splitting, parthenogenesis, and cloning using stem cell lines. Although the Human Reproductive Technology Ordinance is not yet fully operative, this article examines how these prohibitions may adversely impact on basic research and the vision of the Hong Kong scientific community. It concludes that in light of recent scientific developments, it is time to review if the law offers a coherent set of policies in this area.

  15. Activation of ribosomal RNA genes in porcine embryos produced in vitro or by somatic cell nuclear transfer

    DEFF Research Database (Denmark)

    Bjerregaard, Bolette; Pedersen, Hanne Gervi; Jakobsen, Anne Sørig

    2007-01-01

    The onset of ribosomal RNA (rRNA) synthesis occurs during the second half of the third cell cycle, that is, at the four-cell stage, in porcine embryos developed in vivo. In the present study the onset of rRNA synthesis was investigated in porcine embryos produced in vitro (IVP) or by somatic cell...... nuclear transfer (SCNT) using fluorescence in situ hybridization (FISH) with an rDNA probe and subsequent visualization of the nucleolar proteins by silver staining. In the 205 IVP embryos investigated, all two-cell embryos (n = 34) were categorized as transcriptionally inactive. At the late four......-cell stage (n = 45), 38% of the embryos contained 1-3 nuclei with signs of rRNA transcription, indicating an asynchronous transcription initiation. This pattern continued in the following stages, as 78% (n = 47), 47% (n = 42) and 83% (n = 37) of the embryos revealed a mixture of transcriptionally inactive...

  16. EMBRYO RESCUE Dendrobium anosmum Lindl. USING IN VITRO CULTURE

    Directory of Open Access Journals (Sweden)

    Putu Yuni Astriani Dewi

    2016-09-01

    Full Text Available The aim of the research is to analyse germination percentage, effect of coconut water addition in the media to number of last stage embryos and development of final stage D. anosmum Lindl. embryo. Research was conducted at Plant Structure and Development of Laboratory, Department of Biology, Faculty of Mathematics and Natural Sciences University of Udayana and UPT. Balai Benih Induk Tanaman Pangan dan Hortikultura Provinsi Bali from February 2015 to July 2015. Three type of media were employed, i.e. PDA, Organic, MS. Three different concentration of coconut was added to media, i.e. 0 ml/L 50 ml/L, 100 ml/L. Results showed that seed D. anosmum Lindl. on PDA, Organic and MS has not germinated yet on all media, only swollen cells observed. Seed dormancy and maturity of seed were the main factors affecting seed germination. Addition of 100 ml / L coconut water in MS showed that media is capable to increase the formation of final stages embryos (> 32 cells. Embryo development on PDA and Organic largely showed cell stage embryos 1 to 8 cells, while MS media already showed embryo development stages of > 32 cells.

  17. Research and development of a high-performance differential-hybrid charge sensitive preamplifier.

    Science.gov (United States)

    Zeng, Guoqiang; Hu, Chuanhao; Wei, Shilong; Yang, Jian; Li, Qiang; Ge, Liangquan; Tan, Chengjun

    2017-02-01

    A differential-hybrid charge sensitive preamplifier (CSP) was designed by taking a monolithic dual N-Channel Junction Field-effect Transistor (JFET) and a high-speed, low-noise, operational amplifier as the core parts. Input-stage of the circuit employs low-noise differential dual JFET, which ensures high input impedance and low noise. The differential dual transistor makes the quiescent point of the first-stage differential output stable, which is convenient for connecting with the post stage high-speed operational amplifier. Broadband could be amplified by connecting to the double differential dual transistors through the folded cascode-bootstrap. The amplifying circuit which replaces the interstage and post stage discrete components of a traditional CSP with integrated operational amplifier is simpler and more reliable. It simplifies the design of the quiescent point, gives full play to advantages of releasing large open-loop gain, and improves charge-voltage conversion gain stability. Particularly, the charge-voltage conversion gain is larger under a smaller feedback capacitor, thus enabling to gain better signal-noise ratio. The designed CSP was tested, reporting 3.3×10(13) V/C charge sensitivity, about 90ns rise time of signals, 35:1 signal-noise ratio to gamma-rays of (137)Cs (662keV) and a 0.023 fC/pF noise slope. Gamma-rays of (241)Am (59.5keV) were measured by the BPX66 detector and the designed CSP under room temperature, providing 1.97% energy resolution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Perkembangan Praimplantasi Embrio Mencit dengan Materi Genetik yang Berasal dari Parental, Maternal, dan Inti Sel Somatik (PRE-IMPLANTATION DEVELOPMENT OF MOUSE EMBRYO WITH GENETIC MATERIAL DERIVED FROM PARENTAL, MATERNAL AND SOMATIC CELL NUCLEUS

    Directory of Open Access Journals (Sweden)

    Harry Murti

    2014-05-01

    Full Text Available Cloned embryo and parthenogenetic embryo are a potential source of stem cells for regenerativemedicine. Stem cells derived from those embryos are expected to overcome the ethical issues to the use offertilization embryos for therapeutic purposes. The pre-implantation development is a critical step fordeveloping embryos reach the blastocyst stage. The objectives in vivo of this research are to produce mousecloned embryo, parthenogenetic embryo, and fertilized embryo and to study stages of  in vitro pre-implantation development culture. In vivo fertilized embryos, mouse oocytes, and cumulus cells were usedin this study. Treatment was performed on female mice superovulated with PMSG and hCG injections.Two-cell stage of in vivo fertilized embryos were collected on the second day post hCG injection. Clonedembryos were produced through Somatic Cell Nuclear Transfer (SCNT, which included enucleation, nucleartransfer and artificial activation. Parthenogenetic embryos were produced with artificial activationtechnique. The result of the research indicated that SCNT application was able to produce cloned embryos which could develop to blastocyst stage (3,2%. In addition, artificial activation of oocytes could produceparthenogenetic embryos which were able to develop up to the blastocyst stage (8,6%. In conclusion,efficiency level of parthenogenetic embryos that is able to reach the blastocyst stage was higher than in thecloned embryos. Fertilized embryos shows a better development and more efficient compared to in vitrocloned embryos and parthenogenetic embryos cultures.

  19. Genomic imprinting in the Arabidopsis embryo is partly regulated by PRC2.

    Science.gov (United States)

    Raissig, Michael T; Bemer, Marian; Baroux, Célia; Grossniklaus, Ueli

    2013-01-01

    Genomic imprinting results in monoallelic gene expression in a parent-of-origin-dependent manner and is regulated by the differential epigenetic marking of the parental alleles. In plants, genomic imprinting has been primarily described for genes expressed in the endosperm, a tissue nourishing the developing embryo that does not contribute to the next generation. In Arabidopsis, the genes MEDEA (MEA) and PHERES1 (PHE1), which are imprinted in the endosperm, are also expressed in the embryo; whether their embryonic expression is regulated by imprinting or not, however, remains controversial. In contrast, the maternally expressed in embryo 1 (mee1) gene of maize is clearly imprinted in the embryo. We identified several imprinted candidate genes in an allele-specific transcriptome of hybrid Arabidopsis embryos and confirmed parent-of-origin-dependent, monoallelic expression for eleven maternally expressed genes (MEGs) and one paternally expressed gene (PEG) in the embryo, using allele-specific expression analyses and reporter gene assays. Genetic studies indicate that the Polycomb Repressive Complex 2 (PRC2) but not the DNA METHYLTRANSFERASE1 (MET1) is involved in regulating imprinted expression in the embryo. In the seedling, all embryonic MEGs and the PEG are expressed from both parents, suggesting that the imprint is erased during late embryogenesis or early vegetative development. Our finding that several genes are regulated by genomic imprinting in the Arabidopsis embryo clearly demonstrates that this epigenetic phenomenon is not a unique feature of the endosperm in both monocots and dicots.

  20. Genomic imprinting in the Arabidopsis embryo is partly regulated by PRC2.

    Directory of Open Access Journals (Sweden)

    Michael T Raissig

    Full Text Available Genomic imprinting results in monoallelic gene expression in a parent-of-origin-dependent manner and is regulated by the differential epigenetic marking of the parental alleles. In plants, genomic imprinting has been primarily described for genes expressed in the endosperm, a tissue nourishing the developing embryo that does not contribute to the next generation. In Arabidopsis, the genes MEDEA (MEA and PHERES1 (PHE1, which are imprinted in the endosperm, are also expressed in the embryo; whether their embryonic expression is regulated by imprinting or not, however, remains controversial. In contrast, the maternally expressed in embryo 1 (mee1 gene of maize is clearly imprinted in the embryo. We identified several imprinted candidate genes in an allele-specific transcriptome of hybrid Arabidopsis embryos and confirmed parent-of-origin-dependent, monoallelic expression for eleven maternally expressed genes (MEGs and one paternally expressed gene (PEG in the embryo, using allele-specific expression analyses and reporter gene assays. Genetic studies indicate that the Polycomb Repressive Complex 2 (PRC2 but not the DNA METHYLTRANSFERASE1 (MET1 is involved in regulating imprinted expression in the embryo. In the seedling, all embryonic MEGs and the PEG are expressed from both parents, suggesting that the imprint is erased during late embryogenesis or early vegetative development. Our finding that several genes are regulated by genomic imprinting in the Arabidopsis embryo clearly demonstrates that this epigenetic phenomenon is not a unique feature of the endosperm in both monocots and dicots.

  1. Efficient and rapid isolation of early-stage embryos from Arabidopsis thaliana seeds.

    Science.gov (United States)

    Raissig, Michael T; Gagliardini, Valeria; Jaenisch, Johan; Grossniklaus, Ueli; Baroux, Célia

    2013-06-07

    In flowering plants, the embryo develops within a nourishing tissue - the endosperm - surrounded by the maternal seed integuments (or seed coat). As a consequence, the isolation of plant embryos at early stages (1 cell to globular stage) is technically challenging due to their relative inaccessibility. Efficient manual dissection at early stages is strongly impaired by the small size of young Arabidopsis seeds and the adhesiveness of the embryo to the surrounding tissues. Here, we describe a method that allows the efficient isolation of young Arabidopsis embryos, yielding up to 40 embryos in 1 hr to 4 hr, depending on the downstream application. Embryos are released into isolation buffer by slightly crushing 250-750 seeds with a plastic pestle in an Eppendorf tube. A glass microcapillary attached to either a standard laboratory pipette (via a rubber tube) or a hydraulically controlled microinjector is used to collect embryos from droplets placed on a multi-well slide on an inverted light microscope. The technical skills required are simple and easily transferable, and the basic setup does not require costly equipment. Collected embryos are suitable for a variety of downstream applications such as RT-PCR, RNA sequencing, DNA methylation analyses, fluorescence in situ hybridization (FISH), immunostaining, and reporter gene assays.

  2. itFISH: Enhanced Staining by Iterative Fluorescent In Situ Hybridization.

    Science.gov (United States)

    Row, Richard H; Martin, Benjamin L

    2017-03-20

    Fluorescent in situ hybridization (FISH) is an important tool for zebrafish research, particularly when observing the expression of two different genes in the same embryo. Peroxidase-catalyzed deposition of tyramide-conjugated dyes is a widely used and cost-effective approach to performing FISH. A major limitation of the technique is that it does not work well for weakly expressed genes. Here we present a method adapted from planarian research for use in zebrafish that provides a dramatic enhancement of weak staining. By iterating the antibody staining and development steps, a strong signal can be obtained from probes that were previously too weak to detect.

  3. Physical influences on embryo development.

    Science.gov (United States)

    Deeming, D C; Rowlett, K; Simkiss, K

    1987-01-01

    There is a critical period between 3 and 7 days of incubation when the absence of turning in eggs of the domestic fowl leads to increased mortality and decreased embryo growth. This critical period coincides with the time of subembryonic fluid formation, and it is suggested that the absence of turning leads to the presence of unstirred layer effects in fluid secretion. This fluid deficiency persists throughout the subsequent development of the embryo. Experiments on shell-less culture systems support this interpretation in preference to other explanations of embryo death in unturned eggs, which usually refer to chorion adhesion to shell membranes.

  4. New techniques on embryo manipulation.

    Science.gov (United States)

    Escribá, M J; Valbuena, D; Remohí, J; Pellicer, A; Simón, C

    2002-01-01

    For many years, experience has been accumulated on embryo and gamete manipulation in livestock animals. The present work is a review of these techniques and their possible application in human embryology in specific cases. It is possible to manipulate gametes at different levels, producing paternal or maternal haploid embryos (hemicloning), using different techniques including nuclear transfer. At the embryonic stage, considering practical, ethical and legal issues, techniques will be reviewed that include cloning and embryo splitting at the cleavage stage, morula, or blastocyst stage.

  5. Development of globular embryos from the hybridization between 'Pêra Rio' sweet orange and 'Poncã' mandarin Desenvolvimento de embriões globulares de citros provenientes de hibridação entre laranjeira 'Pêra Rio' x tangerineira 'Poncã'

    Directory of Open Access Journals (Sweden)

    Edvan Alves Chagas

    2003-12-01

    Full Text Available This research was undertaken to study the influence of different concentrations of the MT medium, sucrose, vitamins, activated charcoal and gibberellic acid (GA3 on the culture of immature embryos from the crossing between 'Pêra Rio' sweet orange and 'PONCÃ' mandarin. The embryos were excised under aseptic conditions and inoculated in 15 mL of the MT medium according to the following experiments: 1 MT concentrations (0%, 50%, 100%, 150% and 200% supplemented with 0, 30, 60 and 90 g.L-1 of sucrose; 2 vitamins concentrations of the MT (0%, 50%, 100%, 150% and 200% supplemented with 0, 30, 60 and 90 g.L-1 of sucrose; 3 activated charcoal concentrations (0, 0.5, 1, 1.5 and 2 g.L-1 supplemented with GA3 (0, 0.01, 0.1; 1 and 10 mg.L-1. After the inoculation, the embryos were kept in a growth room for 90 days at 27 ± 1ºC, in a 16-hour photoperiod with 32 µmol.m-2.s-1 of irradiance. The best development of embryos at the globular stage was achieved using 50% and 100% of the MT medium plus 60 g.L-1 and 90 g.L-1 of sucrose, respectively, supplemented with 0.01 mg.L-1 of GA3. The addition of activated charcoal or vitamins in the MT medium has shown to be unnecessary to the development of globular embryos.Objetivou-se estudar a influência de diversas concentrações do meio MT, sacarose, vitaminas, carvão ativado e ácido giberélico no cultivo de embriões imaturos oriundos do cruzamento entre laranjeira 'Pêra Rio' x tangerineira 'PONCÃ' . Os embriões foram excisados sob condições assépticas e inoculados em 15 mL do meio de cultura MT, de acordo com cada experimento a seguir: 1 concentrações do meio de cultura MT (0%, 50%, 100%, 150% e 200% combinados com 0, 30, 60 e 90 g.L-1 de sacarose; 2 concentrações de vitaminas do meio MT (0%, 50%, 100%, 150% e 200% combinados com 0, 30, 60 e 90 g.L-1 de sacarose e; 3 concentrações de carvão ativado (0; 0.5; 1; 1.5 e 2 g.L-1 combinados com GA3 (0; 0.01; 0.1; 1 e 10 mg.L-1. Após a inoculação, os

  6. Evidence of Hybrid Institutional Logics in the US Public Research University

    Science.gov (United States)

    Upton, Stevie; Warshaw, Jarrett B.

    2017-01-01

    While the ascendancy of market behaviours in public research universities is well documented, the extent to which universities have transformed themselves into industry-like organisations has been called into question. So to what extent are universities displaying transformation in their core values? The concept of institutional logics, with its…

  7. Evidence of Hybrid Institutional Logics in the US Public Research University

    Science.gov (United States)

    Upton, Stevie; Warshaw, Jarrett B.

    2017-01-01

    While the ascendancy of market behaviours in public research universities is well documented, the extent to which universities have transformed themselves into industry-like organisations has been called into question. So to what extent are universities displaying transformation in their core values? The concept of institutional logics, with its…

  8. Hybrid Separations/Distillation Technology. Research Opportunities for Energy and Emissions Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Eldridge, R. Bruce [Univ. of Texas, Austin, TX (United States); Seibert, A. Frank [Univ. of Texas, Austin, TX (United States); Robinson, Sharon [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rogers, Jo [American Inst. of Chemical Engineers, New York, NY (United States)

    2005-04-01

    This report focuses on improving the existing separations systems for the two largest energy-consuming sectors: the chemicals and petroleum refining industries. It identifies the technical challenges and research needs for improving the efficiency of distillation systems. Areas of growth are also highlighted.

  9. MYRRHA: a Multipurpose Hybrid Research Reactor for high-tech applications

    Energy Technology Data Exchange (ETDEWEB)

    Ait Abderrahim, A

    2002-04-01

    The objective of the MYRRHA project is to develop a multipurpose neutron source for research and development applications on the basis of an Accelerator Driven System (ADS). Main achievements within the MYRRHA project include the completion of the pre-design study of the MYRRHA device, the consolidation of the R and D support programme including hydraulic flow design of the windowless target, the LM corrosion, the material research under irradiation conditions, the visualisation under Pb-Bi; and the development of a solid R and D network around the MYRRHA project via bilateral collaborations and the Fifth Framework Programme by the European Commission. Main achievements in these topical areas in 2001 are summarised.

  10. DAPI Staining of Drosophila Embryos.

    Science.gov (United States)

    Rothwell, Wendy F; Sullivan, William

    2007-10-01

    INTRODUCTIONDrosophila embryos can be stained with specific fluorescent probes or antibodies through either direct or indirect immunofluorescence. In particular, several effective probes exist for visualizing DNA. 4',6-diamidino-2-phenylindole (DAPI) is a commonly used DNA-binding dye. Because it is specific for double-stranded DNA, no prior RNase treatment is required. While the embryo staining method described here uses DAPI, other fluorescent DNA probes can be processed similarly.

  11. In vitro culture of coconut (Cocos nucifera L.) zygotic embryos.

    Science.gov (United States)

    Engelmann, Florent; Malaurie, Bernard; N'Nan, Oulo

    2011-01-01

    Coconut is a very important crop for millions of people in tropical countries. With coconut, in vitro culture protocols have been developed with two main objectives, viz. the large scale production of particular types of coconuts and the international exchange and conservation of coconut germplasm. The methods described in this chapter have been developed in the framework of collaborative activities between research institutes in Côte d'Ivoire and France. Two coconut embryo in vitro collecting protocols have been established, one consisting of storing the disinfected embryos in a KCl solution until they are brought back to the laboratory, where they are re-disinfected and inoculated in vitro under sterile conditions, and the other including in vitro inoculation of the embryos in the field. For international germplasm exchange, zygotic embryos inoculated in vitro in plastic test tubes or endosperm cylinders containing embryos in plastic bags are used. For in vitro culture, embryos are inoculated on semi-solid medium supplemented with sucrose and activated charcoal and placed in the dark, and then transferred to light conditions with the same (solid or liquid) medium once the first true leaf is visible and the root system has started developing.

  12. Live-cell imaging of mitosis in Caenorhabditis elegans embryos.

    Science.gov (United States)

    Powers, James A

    2010-06-01

    Caenorhabditis elegans is a wonderful model system for live imaging studies of mitosis. A huge collection of research tools is readily available to facilitate experimentation. For imaging, C. elegans embryos provide large clear cells, an invariant pattern of cell division, only six chromosomes, a very short cell cycle, and remain healthy and happy at room temperature. Mitosis is a complicated process and the types of research questions being asked about the mechanisms involved are continuously expanding. For each experiment, the details of imaging methods need to be tailored to the question. Specific imaging methods will depend on the microscopy hardware and software available to each researcher. This article presents points to consider when choosing a microscope, designing an imaging experiment, or selecting appropriate worm strains for imaging. A method for mounting C. elegans embryos and guidelines for fluorescence and differential interference contrast imaging of mitosis in live embryos are presented.

  13. Integration of thermal photovoltaic hybrid sensors to the building. Final report july 2004. Integrated research project 6.2; Integration de capteurs hybrides photovoltaiques thermiques au bati. Rapport final juillet 2004. Projet de recherche integre 6.2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    The electricity and the heat are two complementary energies necessary for the accommodation. A thermal solar installation needs the electric power for the coolant fluid flow. This research project concerns the optimization of integrated solutions to the building, providing simultaneously these two energies. This document presents the proposed researches programs: analysis of the socio-economic aspects, the physical phenomena knowledge, simulation of the behavior, experimentation, hybrid components integration, simulation of the photovoltaic modules operating and thermal simulation of an electric converter. (A.L.B.)

  14. Leveraging a clinical research information system to assist biospecimen data and workflow management: a hybrid approach

    Science.gov (United States)

    2011-01-01

    Background Large multi-center clinical studies often involve the collection and analysis of biological samples. It is necessary to ensure timely, complete and accurate recording of analytical results and associated phenotypic and clinical information. The TRIBE-AKI Consortium http://www.yale.edu/tribeaki supports a network of multiple related studies and sample biorepository, thus allowing researchers to take advantage of a larger specimen collection than they might have at an individual institution. Description We describe a biospecimen data management system (BDMS) that supports TRIBE-AKI and is intended for multi-center collaborative clinical studies that involve shipment of biospecimens between sites. This system works in conjunction with a clinical research information system (CRIS) that stores the clinical data associated with the biospecimens, along with other patient-related parameters. Inter-operation between the two systems is mediated by an interactively invoked suite of Web Services, as well as by batch code. We discuss various challenges involved in integration. Conclusions Our experience indicates that an approach that emphasizes inter-operability is reasonably optimal in allowing each system to be utilized for the tasks for which it is best suited. PMID:21884570

  15. SU-E-T-20: A Novel Hybrid CBCT, Bioluminescence and Fluorescence Tomography System for Preclinical Radiation Research

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, B; Eslami, S; Iordachita, I [Johns Hopkins University, Baltimore, Maryland (United States); Yang, Y [University of Miami School of Medicine, Miami, FL (United States); Patterson, M [Hamilton Regional Cancer Ctr., Hamilton, ON (Canada); Wong, J [Johns Hopkins University, Baltimore, MD (United States); Wang, K [Johns Hopkins Hospital, Baltimore, MD (United States)

    2014-06-01

    Purpose: A novel standalone bioluminescence and fluorescence tomography (BLT and FT) system equipped with high resolution CBCT has been built in our group. In this work, we present the system calibration method and validate our system in both phantom and in vivo environment. Methods: The CBCT is acquired by rotating the animal stage while keeping the x-ray source and detector panel static. The optical signal is reflected by the 3-mirror system to a multispectral filter set and then delivered to the CCD camera with f/1.4 lens mounted. Nine fibers passing through the stage and in contact with the mouse skin serve as the light sources for diffuse optical tomography (DOT) and FT. The anatomical information and optical properties acquired from the CBCT and DOT, respectively, are used as the priori information to improve the BLT/FT reconstruction accuracy. Flat field correction for the optical system was acquired at multiple wavelengths. A home-built phantom is used to register the optical and CBCT coordinates. An absolute calibration relating the CCD photon counts rate to the light fluence rate emitted at animal surface was developed to quantify the bioluminescence power or fluorophore concentration. Results: An optical inhomogeneous phantom with 2 light sources (3mm separation) imbedded is used to test the system. The optical signal is mapped onto the mesh generated from CBCT for optical reconstruction. Our preliminary results show that the center of mass can be reconstructed within 2.8mm accuracy. A live mouse with the light source imbedded is also used to validate our system. Liver or lung metastatic luminescence tumor model will be used for further testing. Conclusion: This hybrid system transforms preclinical research to a level that even sub-palpable volume of cells can be imaged rapidly and non-invasively, which largely extends the scope of radiobiological research. The research is supported by the NCI grant R01CA158100-01.

  16. Type II cytokeratin gene expression is indicative of early cell differentiation in the chick embryo

    Energy Technology Data Exchange (ETDEWEB)

    Charlebois, T.S.

    1988-01-01

    Embryonic development in vertebrates appears to involve a series of inductive tissue interactions that lead to regional specializations, which eventually become elaborated in the basic body plan of the embryo. The inductive interactions leading to early regionalization of the embryo are often particularly difficult to evaluate because of the absence of available morphological or biochemical evidence that such events have occurred. In the 36 hour chick embryo, the regional subdivision of the early ectoderm is evidence by a marked lens-forming bias in the head ectoderm, which is absent in the presumptive dorsal epidermis of the trunk region. As a strategy for isolating genes whose differential expression might reflect this regional subdivision, a cDNA library from 36 hour embryos was prepared and screened for differential hybridization to ({sup 32}P)cDNA probes synthesized using template RNA isolated from 36 hour head ectoderm and trunk ectoderm. A cDNA clone (T4) was isolated which hybridizes to transcripts present at much higher levels in trunk ectoderm than in head ectoderm. Partial nucleotide and deduced amino acid sequences of this clone indicate that it represents a gene encoding a type II cytokeratin. The distribution of transcripts complementary to the T4 probe was evaluated in early embryos using RNA gel blot analysis and in situ hybridization to tissue sections.

  17. The genetic heterozygosity and fitness of tetraploid embryos and embryonic stem cells are crucial parameters influencing survival of mice derived from embryonic stem cells by tetraploid embryo aggregation.

    Science.gov (United States)

    Li, Xiangyun; Wei, Wei; Yong, Jun; Jia, Qing; Yu, Yuansong; Di, Keqian

    2005-07-01

    The aim of this paper was to determine whether the genetic background of tetraploid embryos contributed to the survival of mice derived from embryonic stem (ES) cells by tetraploid embryo complementation. Twenty-five newborns were produced by aggregation of hybrid ES cells and tetraploid embryos with different genetic backgrounds. These newborns were entirely derived from ES cells judged by microsatellite DNA (A specific sequence of DNA bases or nucleotides that contains mono, di, tri or tetra repeats) and coat colour phenotype and germline transmission. Fifteen survived to adulthood while seven died of respiratory failure. All newborns were derived from outbred or hybrid tetraploid aggregates and no newborns were from the inbreds. Our results demonstrate that the genetic heterozygosity, fitness of tetraploid embryos and fitness of ES cells are crucial parameters influencing survival of mice derived from ES cells by tetraploid embryo aggregation. In addition, this method represents a simple and efficient procedure for immediate generation of targeted mouse mutants from genetically modified ES cell clones, in contrast to the standard protocol, which involves the production of chimeras and several breeding steps.

  18. Embryo density may affect embryo quality during in vitro culture in a microwell group culture dish.

    Science.gov (United States)

    Lehner, Adam; Kaszas, Zita; Murber, Akos; Rigo, Janos; Urbancsek, Janos; Fancsovits, Peter

    2017-08-01

    Culturing embryos in groups is a common practice in mammalian embryology. Since the introduction of different microwell dishes, it is possible to identify oocytes or embryos individually. As embryo density (embryo-to-volume ratio) may affect the development and viability of the embryos, the purpose of this study was to assess the effect of different embryo densities on embryo quality. Data of 1337 embryos from 228 in vitro fertilization treatment cycles were retrospectively analyzed. Embryos were cultured in a 25 μl microdrop in a microwell group culture dish containing 9 microwells. Three density groups were defined: Group 1 with 2-4 (6.3-12.5 μl/embryo), Group 2 with 5-6 (4.2-5.0 μl/embryo), and Group 3 with 7-9 (2.8-3.6 μl/embryo) embryos. Proportion of good quality embryos was higher in Group 2 on both days (D2: 18.9 vs. 31.5 vs. 24.7%; p Culturing 5-6 embryos together in a culture volume of 25 μl may benefit embryo quality. As low egg number, position, and distance of the embryos may influence embryo quality, results should be interpreted with caution.

  19. Activation of the ribosomal RNA genes late in the third cell cycle of porcine embryos

    DEFF Research Database (Denmark)

    Viuff, Dorthe; Greve, Torben; Holm, Peter

    2002-01-01

    In porcine embryos, nucleoli are first observed during the third postfertilization cell cycle, i.e., at the 4-cell stage. However, direct studies of the initiation of rRNA transcription have not been reported. This transcription was investigated in the present study by simultaneous visualization...... of the rRNA genes and the rRNA by fluorescent in situ hybridization using a porcine 28S rDNA probe and subsequent visualization of argyrophilic nucleolar proteins by silver staining of extracted and fixed nuclei from in vivo-derived porcine embryos (n = 229). Nucleologenesis was observed by transmission...... electron microscopy. In general, the 2-cell and 4-cell embryos fixed at 10 and 20 h postcleavage (hpc) showed no signs of rRNA transcription. Four small clusters of fluorescein isothiocyanate (FITC) labeling were visible in interphase nuclei, consistent with hybridization to the rRNA gene clusters only...

  20. In-ovulo embryo culture and seedling development of cotton (Gossypium hirsutum L.).

    Science.gov (United States)

    Stewart, J M; Hsu, C L

    1977-01-01

    A convenient and reliable method for culturing cotton embryos is needed to obtain interspecific hybrids of this genus. C.A. Beasley and I.P. Ting (Amer. J. Bot. 60, 130, 1973) developed a phytohormone-supplemented medium (BTP) upon which the growth of ovules was similar that of in situ ovules. This medium was examined for in-ovulo embryo culture. Although good ovule growth occurred on BTP no embryos developed to maturity. However, when the medium was supplemented with NH 4 (+) , more than 50% of the ovules produced mature embryos, and many of these germinated precociously after 8-10 weeks of culture. After germination seedlings were established on a separate medium designed to give balanced root and shoot growth. Subsequently young plants could be transferred to pots for greenhouse culture.

  1. Activation of the ribosomal RNA genes late in the third cell cycle of porcine embryos

    DEFF Research Database (Denmark)

    Viuff, Dorthe; Greve, Torben; Holm, Peter

    2002-01-01

    electron microscopy. In general, the 2-cell and 4-cell embryos fixed at 10 and 20 h postcleavage (hpc) showed no signs of rRNA transcription. Four small clusters of fluorescein isothiocyanate (FITC) labeling were visible in interphase nuclei, consistent with hybridization to the rRNA gene clusters only...

  2. Pavia symposium on embryos and stem cells

    Directory of Open Access Journals (Sweden)

    M Boiani

    2009-08-01

    Full Text Available Stem cells occur in very small numbers in adult tissues, in higher numbers in the fetus and its annexes and they can be derived from whole embryos or parts thereof. For a couple of years, stem cells can also be derived straight from somatic cells by retrovirus-mediated transfer of selected genes in culture. Stem cells have varying capacities for self-renewal and differentiation according to their origin, up to the point that they can be propagated in vitro for years and give rise to a wide range of cell types. This makes them suitable means for cell and tissue-replacement therapies. Gaining access to stem cells involves manipulation of living organisms i.e. human beings or animal models. The extent of manipulation ranges from the mere biopsy and culture of body cells in vitro, to their genetic manipulation and back-grafting in vivo.This raises bioethical issues as to whether we should manipulate animal and in particular human life. Many scientific meetings have been organized to present research findings on stem cells and on their potency, differentiation and therapeutic applications for treating disease. In many of these meetings, the ‘mother’ of all stem cells - the embryo - has often been ignored, because embryonic stem cells do not exist as such in the embryo and because the manipulation of the embryo brings up ethical concerns.To make up for this omission, the theme of our meeting was ‘Pluripotency and differentiation in embryos and stem cells’.With a strong sense of purpose and commitment, we managed to hold a two-day symposium concerned with three major topics: 1 natural and induced pluripotency; 2 mechanisms of cell fate control; 3 adult and cancer stem cells. The meeting took place on January 17th-18th 2008 in the beautiful, frescoed halls of Collegio Ghislieri and Borromeo, two foremost colleges in the Pavia campus. A small but prominent group of scientists took part in the meeting – James Adjaye (Germany, Anne Grete Byskov

  3. The NCAR Research Data Archive's Hybrid Approach for Data Discovery and Access

    Science.gov (United States)

    Schuster, D.; Worley, S. J.

    2013-12-01

    The NCAR Research Data Archive (RDA http://rda.ucar.edu) maintains a variety of data discovery and access capabilities for it's 600+ dataset collections to support the varying needs of a diverse user community. In-house developed and standards-based community tools offer services to more than 10,000 users annually. By number of users the largest group is external and access the RDA through web based protocols; the internal NCAR HPC users are fewer in number, but typically access more data volume. This paper will detail the data discovery and access services maintained by the RDA to support both user groups, and show metrics that illustrate how the community is using the services. The distributed search capability enabled by standards-based community tools, such as Geoportal and an OAI-PMH access point that serves multiple metadata standards, provide pathways for external users to initially discover RDA holdings. From here, in-house developed web interfaces leverage primary discovery level metadata databases that support keyword and faceted searches. Internal NCAR HPC users, or those familiar with the RDA, may go directly to the dataset collection of interest and refine their search based on rich file collection metadata. Multiple levels of metadata have proven to be invaluable for discovery within terabyte-sized archives composed of many atmospheric or oceanic levels, hundreds of parameters, and often numerous grid and time resolutions. Once users find the data they want, their access needs may vary as well. A THREDDS data server running on targeted dataset collections enables remote file access through OPENDAP and other web based protocols primarily for external users. In-house developed tools give all users the capability to submit data subset extraction and format conversion requests through scalable, HPC based delayed mode batch processing. Users can monitor their RDA-based data processing progress and receive instructions on how to access the data when it is

  4. Addressing the ethical issues raised by synthetic human entities with embryo-like features

    NARCIS (Netherlands)

    Aach, John; Lunshof, Jeantine; Iyer, Eswar; Church, George M.

    2017-01-01

    The "14-day rule" for embryo research stipulates that experiments with intact human embryos must not allow them to develop beyond 14 days or the appearance of the primitive streak. However, recent experiments showing that suitably cultured human pluripotent stem cells can self organize and recapitul

  5. Comparative study of Msx-1 expression in early normal and vitamin A-deficient avian embryos.

    Science.gov (United States)

    Chen, Y; Kostetskii, I; Zile, M H; Solursh, M

    1995-07-01

    Homeobox-containing genes may play an important role in establishing embryonic patterns during development of vertebrates. Retinoic acid is able to induce expression of Hox genes in cells in culture and to alter expression patterns in the developing vertebrate embryos. Using wholemount in situ hybridization, we have examined and compared the expression patterns of a homeobox-containing gene, Msx-1, in early normal and vitamin A-deficient quail embryos. At gastrulation stage, Msx-1 is primarily expressed in the posterior half of both normal and vitamin A-deficient embryos. However, the gene is expressed wider and stronger in the vitamin A-deficient embryos. At neurulation stages, Msx-1 is continuously expressed in the posterior region up to Hensen's node and in the edge of the neural fold in both normal and vitamin A-deficient embryos. Notably, in the vitamin A-deficient embryos, Msx-1 is expressed more strongly and is also expressed ectopically in the anterior and precardiac regions. These results provide evidence that endogenous retinoids are involved in the normal expression of Msx-1 in avian embryo and that the expression of Msx-1 is downregulated by endogenous and physiological retinoids in vivo during early avian embryogenesis.

  6. Biopsy of human morula-stage embryos: outcome of 215 IVF/ICSI cycles with PGS.

    Directory of Open Access Journals (Sweden)

    Elena E Zakharova

    Full Text Available Preimplantation genetic diagnosis (PGD is commonly performed on biopsies from 6-8-cell-stage embryos or blastocyst trophectoderm obtained on day 3 or 5, respectively. Day 4 human embryos at the morula stage were successfully biopsied. Biopsy was performed on 709 morulae from 215 ICSI cycles with preimplantation genetic screening (PGS, and 3-7 cells were obtained from each embryo. The most common vital aneuploidies (chromosomes X/Y, 21 were screened by fluorescence in situ hybridization (FISH. No aneuploidy was observed in 72.7% of embryos, 91% of those developed to blastocysts. Embryos were transferred on days 5-6. Clinical pregnancy was obtained in 32.8% of cases, and 60 babies were born. Patients who underwent ICSI/PGS treatment were compared with those who underwent standard ICSI treatment by examining the percentage of blastocysts, pregnancy rate, gestational length, birth height and weight. No significant differences in these parameters were observed between the groups. Day 4 biopsy procedure does not adversely affect embryo development in vitro or in vivo. The increased number of cells obtained by biopsy of morulae might facilitate diagnostic screening. There is enough time after biopsy to obtain PGD results for embryo transfer on day 5-6 in the current IVF cycle.

  7. Impact of different patterns of sperm chromosomal abnormalities on the chromosomal constitution of preimplantation embryos.

    Science.gov (United States)

    Rodrigo, Lorena; Peinado, Vanessa; Mateu, Emilia; Remohí, José; Pellicer, Antonio; Simón, Carlos; Gil-Salom, Manuel; Rubio, Carmen

    2010-09-01

    To evaluate the effect of sperm chromosome abnormalities--disomy for sex chromosomes and diploidy--in the chromosomal constitution of preimplantation embryos. Retrospective cohort study. Infertility clinic. Three groups: 46,XY infertile men with increased incidence of sex chromosome disomy in sperm; 46,XY infertile men with increased diploidy rates in sperm; 47,XYY infertile men with increased sex chromosome disomy and diploidy rates in sperm. Sperm collection for fluorescence in situ hybridization analysis. Embryo biopsy for preimplantation genetic screening. Frequencies of numerical abnormalities in sperm for chromosomes 13, 18, 21, X, and Y, and in embryos for chromosomes 13, 16, 18, 21, 22, X, and Y. A significant increase of chromosomally abnormal and mosaic embryos was observed in the three study groups compared with controls. Those sperm samples with increased sex chromosome disomy rates produced significantly higher percentages of aneuploid embryos, with a threefold increase for sex chromosomes. Sperm samples with increased diploidy rates were mainly associated to the production of triploid embryos. A strong correlation between sperm and embryo chromosomal constitution has been shown in infertile men with 46,XY and 47,XYY karyotypes. Copyright (c) 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  8. Chromosomal mosaicism in mouse two-cell embryos after paternal exposure to acrylamide

    Energy Technology Data Exchange (ETDEWEB)

    Marchetti, Francesco; Bishop, Jack; Lowe, Xiu; Wyrobek, Andrew J

    2008-10-14

    Chromosomal mosaicism in human preimplantation embryos is a common cause ofspontaneous abortions, however, our knowledge of its etiology is limited. We used multicolor fluorescence in situ hybridization (FISH) painting to investigate whether paternally-transmitted chromosomal aberrations result in mosaicism in mouse 2-cell embryos. Paternal exposure to acrylamide, an important industrial chemical also found in tobacco smoke and generated during the cooking process of starchy foods, produced significant increases in chromosomally defective 2-cell embryos, however, the effects were transient primarily affecting the postmeiotic stages of spermatogenesis. Comparisons with our previous study of zygotes demonstrated similar frequencies of chromosomally abnormal zygotes and 2-cell embryos suggesting that there was no apparent selection against numerical or structural chromosomal aberrations. However, the majority of affected 2-cell embryos were mosaics showing different chromosomal abnormalities in the two blastomeric metaphases. Analyses of chromosomal aberrations in zygotes and 2-cell embryos showed a tendency for loss of acentric fragments during the first mitotic division ofembryogenesis, while both dicentrics and translocations apparently underwent propersegregation. These results suggest that embryonic development can proceed up to the end of the second cell cycle of development in the presence of abnormal paternal chromosomes and that even dicentrics can persist through cell division. The high incidence of chromosomally mosaic 2-cell embryos suggests that the first mitotic division of embryogenesis is prone to missegregation errors and that paternally-transmitted chromosomal abnromalities increase the risk of missegregation leading to embryonic mosaicism.

  9. The research of clean bottle and bottle embryo recycle in the PP bottle infusion production%洁净瓶胚料在塑瓶大输液生产中回收利用的研究

    Institute of Scientific and Technical Information of China (English)

    崔良峰; 黄桂华

    2015-01-01

    Objective Crush the clean plastic bottles and bottle embryos into a certain size of particles,add new pp ag-gregate mixed according to certain proportion,blow them into PP bottles again,the pp bottles will be used in the production of pp bottle infusions. Through the identification of the risk and influence factor during the recycle of the pp materials,take corresponding control measures to ensure the quality of the final products not be affected. Methods ①Identify the risk,re-search in the risk control and production process according the risk point. ②Select pp aggregate from 3 different manufactur-ers,research the different proportions of making pp bottles. ③Use the pp bottles in the production of 0. 9% sodium chloride injection and 5% glucose injection,test,research the accelerated stability study and the package material compatibili-ty. Make sure if there is quality difference between the new products which uses mixing aggregate and original products. Re-sults and Conclusion Recycle the homogeneous clean plastic bottles and bottle embryos with a certain propor-tion. Research the accelerated stability study and the package material compatibility,and compared with normal production, there is no obvious difference in the data,and the biological experiments meet the requirement at the same time. This method can ensure the product safety and stability.%目的:将塑瓶大输液生产中灌装药液前产生的洁净瓶、胚,重新粉碎成一定粒径的颗粒后,与新 PP 粒料按一定比例混合后,重新吹制成 PP 输液瓶,用于 PP 塑瓶大输液产品的生产。通过对回收利用过程中的各种风险和影响因素进行识别,采取针对性的控制措施,确保最终产品质量不受影响。方法①进行风险识别,确定风险点并据此进行风险控制与工艺研究;②选取3个不同厂家的 PP 粒料,进行不同混合比例的制瓶研究;③将不同混合比例的 PP 瓶分别用于0.9%

  10. What is the preimplantation embryo?

    Science.gov (United States)

    Krones, Tanja; Schlüter, Elmar; Neuwohner, Elke; El Ansari, Susan; Wissner, Thomas; Richter, Gerd

    2006-07-01

    We present results from our 'bioethical field studies', which explore and compare the views of experts, patients and the general public on the beginning of human life and the status of the preimplantation embryo in Germany. Using a qualitative and quantitative multi-method approach, we found crucial differences in the categorization of the beginning of human life within the expert group (representative samples of human geneticists n=104, ethicists n=168, midwives n=294, obstetricians n=147, paediatricians n=166), and between expert and lay samples (IVF couples n=108, high genetic risk couples n=324, general population n=1017). The majority of lay respondents as well as paediatricians and obstetricians chose nidation, the moment when the implantation of the fertilized egg into the uterus takes place, as the crucial boundary that marks the beginning of human life, whereas the majority of (female) human geneticists, ethicists and midwives voted for conception as the decisive point in time. The views of all groups on the status of the preimplantation embryo differed from the assumptions underlying German legislation (Embryo Protection Act). Religiousness and religious affiliation, gender, attitudes towards disabled people, post-material values and a present desire for a child were identified as independent factors influencing attitudes towards the preimplantation embryo in the population sample. The results are discussed within a broader philosophical and social science perspective of constructivism versus essentialism, proposing a truly interdisciplinary approach to such bioethical core issues as new reproductive technologies and the status of the preimplantation embryo.

  11. Effect of the size of zona pellucida opening on hatching in the common marmoset monkey (Callithrix jacchus) embryo.

    Science.gov (United States)

    Ishibashi, Hidetoshi; Motohashi, Hideyuki H; Kumon, Mami; Yamamoto, Kazuhiro; Okada, Hironori; Okada, Takashi; Seki, Kazuhiko

    2013-11-01

    The use of the common marmoset monkey in biomedical research has increased recently, and further attention has been devoted to this model after the successful production of transgenic marmosets. To extend genetic engineering approaches to widespread biomedical research fields, efficient prolonged in vitro culturing of embryo development is necessary. We aimed to evaluate the effects of the size of the zona pellucida opening on promoting the hatching process in the marmoset embryo. Piezo-microdrilling of a 6-μm opening in eight embryos resulted in four partially hatched embryos and one hatched embryo after 5 days of culture. Piezo-microdrilling a 20-μm opening in 11 embryos resulted in nine partial hatchings and no hatched embryos. Piezo-scraping an 80-μm opening in six embryos resulted in no partially hatched embryos and five hatched embryos. These results suggest that an 80-μm opening, rather than 6-μm or 20-μm openings, is suitable to complete the hatching process in the marmoset embryo.

  12. Principles guiding embryo selection following genome-wide haplotyping of preimplantation embryos.

    Science.gov (United States)

    Dimitriadou, Eftychia; Melotte, Cindy; Debrock, Sophie; Esteki, Masoud Zamani; Dierickx, Kris; Voet, Thierry; Devriendt, Koen; de Ravel, Thomy; Legius, Eric; Peeraer, Karen; Meuleman, Christel; Vermeesch, Joris Robert

    2017-03-01

    genome-wide methods for PGD in many different centers world-wide as well as the results of ongoing scientific research. Our embryo selection principles have a profound impact on the organization of PGD operations and on the information that is transferred among the genetic unit, the fertility clinic and the patients. These principles are also important for the organization of pre- and post-counseling and influence the interpretation and reporting of preimplantation genotyping results. As novel genome-wide approaches for embryo selection are revolutionizing the field of reproductive genetics, national and international discussions to set general guidelines are warranted. The European Union's Research and Innovation funding programs FP7-PEOPLE-2012-IAPP SARM: 324509 and Horizon 2020 WIDENLIFE: 692065 to J.R.V., T.V., E.D. and M.Z.E. J.R.V., T.V. and M.Z.E. have patents ZL910050-PCT/EP2011/060211-WO/2011/157846 ('Methods for haplotyping single cells') with royalties paid and ZL913096-PCT/EP2014/068315-WO/2015/028576 ('Haplotyping and copy-number typing using polymorphic variant allelic frequencies') with royalties paid, licensed to Cartagenia (Agilent technologies). J.R.V. also has a patent ZL91 2076-PCT/EP20 one 3/070858 ('High throughout genotyping by sequencing') with royalties paid. N/A.

  13. EFFICIENCY IN THE FORMATION OF STABLE EMBRYOGENIC LINES AND SOMATIC EMBRYO REGENERATION IN NORWAY SPRUCE AND HYBRID LARCH%挪威云杉及杂种落叶松稳定胚性细胞系及体胚再生系统的建立

    Institute of Scientific and Technical Information of China (English)

    DietrichEwald; 胡建军

    2003-01-01

    授粉袋)的相比较,发现人工授粉袋的使用延迟了合子胚的发育.我们的实验中成熟合子胚没有形成胚性细胞系,只有未成熟合子胚形成了胚性细胞系.1995年用落叶松未成熟合子胚建立的胚性细胞系没有形成体胚,而1996年建立的4个胚性细胞系得到了可以移栽到温室中的再生植株.1.5 a的连续继代培养以后,大多数的杂种落叶松和挪威云杉的胚性细胞系的再生能力都下降.导致这种现象可能有多种原因包括培养物的老化以及出现难以检测到的内生细菌.尽管一组实验从最初培养即用了抗生素,但没有收效.因此目前只得到少量的稳定胚性细胞系(<5%),长期继代后丧失再生能力及无法成功移栽到土壤都是植株再生的重要的限制因素,有待进一步研究克服这些困难.%The induction of embryogenic cultures from controlled pollinated seeds was tested for Norway Spruce and hybrid Larch in different years. The amount of established stable lines in both species was determined. A reduction in the regeneration potential of the lines was observed after a few years. In Norway Spruce, contrary to hybrid Larch, only some established lines were able to grow in suspension culture. Established embryogenic lines of both species not in all cases were able to regenerate somatic embryos. The use of polyethyleneglycoll and the mode of abscisic acid sterilisation were found to be factors responsible for the number of mature somatic embryos formed. The transfer of somatic embryos into germinating plants and later on to the soil was possible for hybrid Larch lines. Insufficient root formation in Norway Spruce somatic embryos influenced the transfer to the soil negatively. The low number of stable embryogenic lines (<5%) formed in both species confirmed that this step is the most limiting one within this plant regeneration method at present.

  14. Can a genetically-modified organism-containing diet influence embryo development? A preliminary study on pre-implantation mouse embryos

    Directory of Open Access Journals (Sweden)

    B Cisterna

    2009-08-01

    Full Text Available In eukaryotic cells, pre-mRNAs undergo several transformation steps to generate mature mRNAs. Recent studies have demonstrated that a diet containing a genetically modified (GM soybean can induce modifications of nuclear constituents involved in RNA processing in some tissues of young, adult and old mice. On this basis, we have investigated the ultrastructural and immunocytochemical features of pre-implantation embryos from mice fed either GM or non- GM soybean in order to verify whether the parental diet can affect the morpho-functional development of the embryonic ribonucleoprotein structural constituents involved in premRNA pathways. Morphological observations revealed that the general aspect of embryo nuclear components is similar in the two experimental groups. However, immunocytochemical and in situ hybridization results suggest a temporary decrease of pre-mRNA transcription and splicing in 2-cell embryos and a resumption in 4-8-cell embryos from mice fed GM soybean; moreover, pre-mRNA maturation seems to be less efficient in both 2-cell and 4-8-cell embryos from GM-fed mice than in controls. Although our results are still preliminary and limited to the pre-implantation phases, the results of this study encourage deepening on the effects of food components and/or contaminants on embryo development.

  15. Preparation of ZnO/CdS/BC Photocatalyst Hybrid Fiber and Research of Its Photocatalytic Properties

    Directory of Open Access Journals (Sweden)

    Beibei Dai

    2015-01-01

    Full Text Available An environment-friendly biomaterial bacterial cellulose (BC is introduced to substitute general organic polymers to assist the preparation of ZnO/CdS/BC photocatalyst hybrid nanofiber through coprecipitation method under the low-temperature condition. The XRD, XPS, and SEM results show that high load of ZnO/CdS/BC ternary hybrid fiber can be produced. TGA curves scan shows that ZnO/CdS/BC hybrid fiber has better thermal properties than bacterial cellulose. The UV-Vis spectra of the ZnO/CdS/BC hybrid nanofiber (0, 10, 20, and 50 wt%, resp. show that photocatalytic activities of ZnO/CdS/BC are influenced by the added amount of CdS. The degradation curve of methyl shows that ZnO/CdS/BC nanohybrid fibers exhibit excellent photocatalytic efficiency.

  16. Cell adhesion in embryo morphogenesis.

    Science.gov (United States)

    Barone, Vanessa; Heisenberg, Carl-Philipp

    2012-02-01

    Visualizing and analyzing shape changes at various scales, ranging from single molecules to whole organisms, are essential for understanding complex morphogenetic processes, such as early embryonic development. Embryo morphogenesis relies on the interplay between different tissues, the properties of which are again determined by the interaction between their constituent cells. Cell interactions, on the other hand, are controlled by various molecules, such as signaling and adhesion molecules, which in order to exert their functions need to be spatiotemporally organized within and between the interacting cells. In this review, we will focus on the role of cell adhesion functioning at different scales to organize cell, tissue and embryo morphogenesis. We will specifically ask how the subcellular distribution of adhesion molecules controls the formation of cell-cell contacts, how cell-cell contacts determine tissue shape, and how tissue interactions regulate embryo morphogenesis.

  17. Research Update: Challenges for high-efficiency hybrid lead-halide perovskite LEDs and the path towards electrically pumped lasing

    OpenAIRE

    Guangru Li; Michael Price; Felix Deschler

    2016-01-01

    Hybrid lead-halide perovskites have emerged as promising solution-processed semiconductor materials for thin-film optoelectronics. In this review, we discuss current challenges in perovskite LED performance, using thin-film and nano-crystalline perovskite as emitter layers, and look at device performance and stability. Fabrication of electrically pumped, optical-feedback devices with hybrid lead halide perovskites as gain medium is a future challenge, initiated by the demonstration of optical...

  18. Overview of initial research into the effects of strong vortex flow on hybrid rocket combustion and performance

    Science.gov (United States)

    Gloyer, P.; Knuth, William H.; Goodman, J.

    1993-01-01

    An examination of the effect of vortex flow on hybrid rocket combustion and performance is underway. Emphasis is on response of the fuel regression rate when subjected to vortex flow. Initial results show that there is a definite effect of the vortex on fuel regression rate. Future work will focus on quantitatively measuring this regression rate. This work is part of an overall program to develop an ultra low cost fuel system for hybrid rocket engines.

  19. A simple method for producing tetraploid porcine parthenogenetic embryos.

    Science.gov (United States)

    Sembon, S; Fuchimoto, D; Iwamoto, M; Suzuki, S; Yoshioka, K; Onishi, A

    2011-09-01

    The objective was to produce porcine tetraploid parthenogenetic embryos using cytochalasin B, which inhibits polar body extrusion. Porcine cumulus-enclosed oocytes aspirated from antral follicles were cultured for 51 h, and treated with cytochalasin B from 35 h to 42 h after the start of culture. After maturation culture, 74.7% (2074/2775) of oocytes treated with cytochalasin B did not extrude a polar body (0PB oocytes). In contrast, 80.4% (1931/2403) of control oocytes extruded a polar body (1PB oocytes). The 0PB oocytes were electrically stimulated, treated with cytochalasin B again for 3 h, and then cultured without cytochalasin B. Six days after electrical stimulation, 49.8% (321/644) reached the blastocyst stage. The number of cells in these blastocysts derived from 0PB oocytes was significantly lower than that from 1PB oocytes (0PB: 24.9 ± 10.6; 1PB: 43.0 ± 17.1; mean ± SD). A porcine chromosome 1-specific sequence was detected in parthenogenetic 0PB embryos by fluorescence in situ hybridization (FISH) analysis. Typical pronucleus-stage samples derived from 0PB embryos had two pronuclei, each with two signals. In two-cell and blastocyst-stage embryos, four signals were detected in each nucleus derived from 0PB embryos. We inferred that 0PB oocytes, which had a tetraploid number of chromosomes, started to develop as tetraploid parthenotes after electrical stimulation, and that tetraploid status was stably maintained during early embryonic development, at least until the blastocyst stage.

  20. In amnio MRI of mouse embryos.

    Directory of Open Access Journals (Sweden)

    Thomas A Roberts

    Full Text Available Mouse embryo imaging is conventionally carried out on ex vivo embryos excised from the amniotic sac, omitting vital structures and abnormalities external to the body. Here, we present an in amnio MR imaging methodology in which the mouse embryo is retained in the amniotic sac and demonstrate how important embryonic structures can be visualised in 3D with high spatial resolution (100 µm/px. To illustrate the utility of in amnio imaging, we subsequently apply the technique to examine abnormal mouse embryos with abdominal wall defects. Mouse embryos at E17.5 were imaged and compared, including three normal phenotype embryos, an abnormal embryo with a clear exomphalos defect, and one with a suspected gastroschisis phenotype. Embryos were excised from the mother ensuring the amnion remained intact and stereo microscopy was performed. Embryos were next embedded in agarose for 3D, high resolution MRI on a 9.4T scanner. Identification of the abnormal embryo phenotypes was not possible using stereo microscopy or conventional ex vivo MRI. Using in amnio MRI, we determined that the abnormal embryos had an exomphalos phenotype with varying severities. In amnio MRI is ideally suited to investigate the complex relationship between embryo and amnion, together with screening for other abnormalities located outside of the mouse embryo, providing a valuable complement to histology and existing imaging methods available to the phenotyping community.

  1. PCOS胚胎着床障碍中西医病因研究进展%Progress of Traditional Chinese and Western Medicine Research in Embryo Implantation Disorders Cause about PCOS

    Institute of Scientific and Technical Information of China (English)

    安洁; 周惠芳

    2012-01-01

    多囊卵巢综合征(PCOS)是一种发病多因性、临床表现多态性的内分泌综合征,也是导致育龄期女性月经紊乱及不孕最常见的原因之一.临床PCOS患者在内分泌紊乱纠正、自然排卵或促排后仍出现低妊娠率、高流产率的现象.而胚胎着床又是一复杂的生理过程,受诸多因素调节.近年来,众多医家从传统医学的理、法、方、药及现代医学的角度联合分析了胚胎着床障碍的特点.文章就相关研究进展进行了综述.%Polyeystio ovary syndrome endocrine ( PCOS ) is a kind of syndrome caused by more reasons, and has mutiple clinical manifestations, also is the cause of reproductive age women's menstrual disorder and one of the most common cause of infertility.Clinical PCOS patients in the endocrine disorder correct process, natural ovulation could appear low pregnancy rate, high abortion rate. And embryo implantation is a complex physiological process, which is influenced by many factors. In recent years, many physicians analyzed the characteristics of embryonic implantation obstacles from traditional medical science, principle and modern medicine the characteristics of embryonic implantation obstacles.This paper summarized the related research progress.

  2. Successful cloning of the Yucatan minipig using commercial/occidental breeds as oocyte donors and embryo recipients.

    Science.gov (United States)

    Estrada, Jose L; Collins, Bruce; York, Abby; Bischoff, Steve; Sommer, Jeff; Tsai, Shengdar; Petters, Robert M; Piedrahita, Jorge A

    2008-06-01

    The widespread application of porcine SCNT to biomedical research is being hampered by the large adult size (300-600 lbs) of the commercial breeds commonly used for SCNT. The Yucatan minipig, in contrast, has an adult weight of 140-150 lbs and a long history of utility in biomedical research. In order to combine the wide availability of commercial swine with the biomedical value of the Yucatan minipig, we utilized SCNT using the Yucatan as nuclear donors and commercial swine as both oocyte donors and recipients. Of six recipient gilts receiving 631 SCNT embryos, three went to term and delivered seven piglets, four of which survived to adulthood. Additionally, we obtained fetal fibroblasts from a cloned Yucatan and used them for a second round of SCNT. Of three recipients receiving 315 reconstructed embryos, one went to term and delivered three piglets, one of which survived to adulthood. Both microsatellite and D-loop sequence analysis confirmed that all of the piglets generated were nuclear-mitochondrial hybrids carrying Yucatan nuclear DNA and commercial breed mitochondrial DNA. This report shows that it is possible to produce viable Yucatan SCNT clones and opens up the possibility of developing valuable biomedical models in this porcine breed.

  3. Marine Fish Hybridization

    KAUST Repository

    He, Song

    2017-04-01

    Natural hybridization is reproduction (without artificial influence) between two or more species/populations which are distinguishable from each other by heritable characters. Natural hybridizations among marine fishes were highly underappreciated due to limited research effort; it seems that this phenomenon occurs more often than is commonly recognized. As hybridization plays an important role in biodiversity processes in the marine environment, detecting hybridization events and investigating hybridization is important to understand and protect biodiversity. The first chapter sets the framework for this disseration study. The Cohesion Species Concept was selected as the working definition of a species for this study as it can handle marine fish hybridization events. The concept does not require restrictive species boundaries. A general history and background of natural hybridization in marine fishes is reviewed during in chapter as well. Four marine fish hybridization cases were examed and documented in Chapters 2 to 5. In each case study, at least one diagnostic nuclear marker, screened from among ~14 candidate markers, was found to discriminate the putative hybridizing parent species. To further investigate genetic evidence to support the hybrid status for each hybrid offspring in each case, haploweb analysis on diagnostic markers (nuclear and/or mitochondrial) and the DAPC/PCA analysis on microsatellite data were used. By combining the genetic evidences, morphological traits, and ecological observations together, the potential reasons that triggered each hybridization events and the potential genetic/ecology effects could be discussed. In the last chapter, sequences from 82 pairs of hybridizing parents species (for which COI barcoding sequences were available either on GenBank or in our lab) were collected. By comparing the COI fragment p-distance between each hybridizing parent species, some general questions about marine fish hybridization were discussed: Is

  4. Embryo malposition as a potential mechanism for mercury-induced hatching failure in bird eggs

    Science.gov (United States)

    Herring, G.; Ackerman, J.T.; Eagles-Smith, C. A.

    2010-01-01

    We examined the prevalence of embryo malpositions and deformities in relation to total mercury (THg) and selenium (Se) concentrations in American avocet (Recurvirostra americana), black-necked stilt (Himantopus mexicanus), and Forster's tern (Sterna forsteri) eggs in San Francisco Bay (CA, USA) during 2005 to 2007. Overall, 11% of embryos were malpositioned in eggs ???18 d of age (n=282) and 2% of embryos were deformed in eggs ???13 d of age (n=470). Considering only those eggs that failed to hatch (n=62), malpositions occurred in 24% of eggs ???18 d of age and deformities occurred in 7% of eggs ???13 d of age. The probability of an embryo being malpositioned increased with egg THg concentrations in Forster's terns, but not in avocets or stilts. The probability of embryo deformity was not related to egg THg concentrations in any species. Using a reduced dataset with both Se and THg concentrations measured in eggs (n=87), we found no interaction between Se and THg on the probability of an embryo being malpositioned or deformed. Results of the present study indicate that embryo malpositions were prevalent in waterbird eggs that failed to hatch and the likelihood of an embryo being malpositioned increased with egg THg concentrations in Forster's terns. We hypothesize that malpositioning of avian embryos may be one reason for mercury-related hatching failure that occurs late in incubation, but further research is needed to elucidate this potential mechanism. ?? 2010 SETAC.

  5. Future aspects of micromanipualtion with embryos for

    African Journals Online (AJOL)

    Embryo micromanipulation techniques and their potential genetic impact in dairy cattle ... bovine embryos and the subsequent transfer of halfembryos has reached a .... (e) to provide synchronously developing pronuclear srage ova for nuclear ...

  6. Embryo splitting: a role in infertility?

    Science.gov (United States)

    Wood, C

    2001-01-01

    Embryo splitting may be used to increase the potential fertility of couples requiring IVF. Using cattle as a model, it is possible to increase pregnancy rates from 70% per transfer of good quality in-vivo-produced embryos, to 110% by transferring the two demi-embryos resulting from the bisection of one embryo. The 30-40% greater chance of conception would reduce costs for the government, health authorities and patients, and reduce stress, time and complications for women having IVF treatment. Embryo splitting may also provide donor embryos for infertile couples that cannot conceive naturally or with IVF. The shortage of children for adoption and donor embryos may be overcome by the production of demi-embryos.

  7. Cloning in cattle: from embryo splitting to somatic nuclear transfer.

    Science.gov (United States)

    Heyman, Y; Vignon, X; Chesné, P; Le Bourhis, D; Marchal, J; Renard, J P

    1998-01-01

    The ability to obtain genetically identical offspring in cattle (clones) is useful for research and for potential applications to breeding schemes. Experimental possibilities for generating such animals have evolved considerably in the last two decades. Embryo splitting has become a relatively simple technique but is limited to twinning. Embryonic nuclear transfer has improved and is associated with sexing to generate sets of clones despite a great variability of results between parent embryos. The factors of progress are reviewed here. Recently, somatic cells used as a source of nuclei in bovine nuclear transfer has been demonstrated. Here we present the results of the developmental potential of nuclei from skin and muscle cells.

  8. Macroevolutionary developmental biology: Embryos, fossils, and phylogenies.

    Science.gov (United States)

    Organ, Chris L; Cooper, Lisa Noelle; Hieronymus, Tobin L

    2015-10-01

    The field of evolutionary developmental biology is broadly focused on identifying the genetic and developmental mechanisms underlying morphological diversity. Connecting the genotype with the phenotype means that evo-devo research often considers a wide range of evidence, from genetics and morphology to fossils. In this commentary, we provide an overview and framework for integrating fossil ontogenetic data with developmental data using phylogenetic comparative methods to test macroevolutionary hypotheses. We survey the vertebrate fossil record of preserved embryos and discuss how phylogenetic comparative methods can integrate data from developmental genetics and paleontology. Fossil embryos provide limited, yet critical, developmental data from deep time. They help constrain when developmental innovations first appeared during the history of life and also reveal the order in which related morphologies evolved. Phylogenetic comparative methods provide a powerful statistical approach that allows evo-devo researchers to infer the presence of nonpreserved developmental traits in fossil species and to detect discordant evolutionary patterns and processes across levels of biological organization.

  9. Developmental imaging: the avian embryo hatches to the challenge.

    Science.gov (United States)

    Kulesa, Paul M; McKinney, Mary C; McLennan, Rebecca

    2013-06-01

    The avian embryo provides a multifaceted model to study developmental mechanisms because of its accessibility to microsurgery, fluorescence cell labeling, in vivo imaging, and molecular manipulation. Early two-dimensional planar growth of the avian embryo mimics human development and provides unique access to complex cell migration patterns using light microscopy. Later developmental events continue to permit access to both light and other imaging modalities, making the avian embryo an excellent model for developmental imaging. For example, significant insights into cell and tissue behaviors within the primitive streak, craniofacial region, and cardiovascular and peripheral nervous systems have come from avian embryo studies. In this review, we provide an update to recent advances in embryo and tissue slice culture and imaging, fluorescence cell labeling, and gene profiling. We focus on how technical advances in the chick and quail provide a clearer understanding of how embryonic cell dynamics are beautifully choreographed in space and time to sculpt cells into functioning structures. We summarize how these technical advances help us to better understand basic developmental mechanisms that may lead to clinical research into human birth defects and tissue repair.

  10. An in vivo culture system for human embryos using an encapsulation technology: a pilot study

    Science.gov (United States)

    Blockeel, C.; Mock, P.; Verheyen, G.; Bouche, N.; Le Goff, Ph.; Heyman, Y.; Wrenzycki, C.; Höffmann, K.; Niemann, H.; Haentjens, P.; de Los Santos, M.J.; Fernandez-Sanchez, M.; Velasco, M.; Aebischer, P.; Devroey, P.; Simón, C.

    2009-01-01

    BACKGROUND Animal studies have demonstrated better embryo development in vivo than in vitro. This pilot study tested the feasibility of using a novel in utero culture system (IUCS) to obtain normal human fertilization and embryo development. METHODS The IUCS device comprised a perforated silicone hollow tube. The study included 13 patients (<36 years) undergoing a first intracytoplasmic sperm injection (ICSI) treatment and 167 metaphase II oocytes in three groups. In Group 1, 1–2 h after ICSI, sibling oocytes were assigned to IUCS or conventional in vitro culture. The device was retrieved on Day 1, and all zygotes were cultured in vitro till Day 5. In Group 2, fertilized oocytes were assigned on Day 1, embryos retrieved on Day 3 and all embryos cultured till Day 5. In Group 3, after Day 0 assignment, embryos were retrieved on Day 3 for blastomere biopsy and fluorescence in situ hybridization (FISH) and cultured until Day 5. The highest quality blastocysts were transferred on Day 5. RESULTS Fertilization and embryo development were comparable in the in vitro and IUCS arms, with a tendency towards better embryo quality in the IUCS. FISH analysis in Group 3 revealed more normal embryos using the IUCS (P = 0.049). Three clinical pregnancies and live births were obtained: two from the IUCS arm and one from the in vitro arm. CONCLUSIONS Our pilot study shows that this new IUCS appears to be feasible and safe, supporting normal fertilization, embryo development and normal chromosomal segregation. Furthermore, live births are possible after the transient presence of a silicone device in the uterus.Clinicaltrials.gov: NCT00480103. PMID:19273881

  11. The science, fiction, and reality of embryo cloning.

    Science.gov (United States)

    Cohen, Jacques; Tomkin, Giles

    1994-09-01

    Although many scientists view cloning as a useful procedure for scientific research into early embryo development -- one that cannot currently be used to produce multiple copies of humans -- the popular literature has led some individuals to view it as sinister. To address the concerns of the public, various conceptions of cloning are distinguished and their basis in fact analyzed. The possible uses, benefits, and detriments of both embryo splitting and nuclear transplantation are explained. Once the nature and purposes of cloning are understood, and the distinctive ethical dilemmas created by embryo splitting and nuclear transplantation are sorted out, these procedures should be clinically implemented to assist in vitro fertilization treatment for those who are infertile and to further other therapeutic and investigational efforts in medicine.

  12. Embryo growth in mature celery seeds

    NARCIS (Netherlands)

    Toorn, van der P.

    1989-01-01

    Germination of celery seeds is slow, due to the need for embryo growth before radicle protrusion can occur. Germination rate was correlated with embryo growth rate. Celery seeds with different embryo growth rates were obtained with fluid density separation of a seed lot. Low density seeds g

  13. Embryo temperature during incubation: practice and theory

    NARCIS (Netherlands)

    Lourens, A.

    2008-01-01

    (Key words: incubation, embryo temperature, embryonic development, heat production, heat loss) Until recently, all incubator studies were performed using a constant machine temperature (MT). But it is embryo temperature (ET) that is of importance to the embryo, and not MT. In practice, MT is often

  14. Improving embryo quality in assisted reproduction

    NARCIS (Netherlands)

    Mantikou, E.

    2013-01-01

    The goal of this thesis was to improve embryo quality in assisted reproductive technologies by gaining more insight into human preimplantation embryo development and by improving in vitro culture conditions. To do so, we investigated an intriguing feature of the human preimplantation embryo, i.e. it

  15. Embryo growth in mature celery seeds

    NARCIS (Netherlands)

    Toorn, van der P.

    1989-01-01

    Germination of celery seeds is slow, due to the need for embryo growth before radicle protrusion can occur. Germination rate was correlated with embryo growth rate. Celery seeds with different embryo growth rates were obtained with fluid density separation of a seed lot. Low density seeds

  16. Developmental potential of embryonic cells in a nucleocytoplasmic hybrid formed using a goldfish haploid nucleus and loach egg cytoplasm.

    Science.gov (United States)

    Fujimoto, Takafumi; Saito, Taiju; Sakao, Suzu; Arai, Katsutoshi; Yamaha, Etsuro

    2010-01-01

    In teleosts, viable nucleocytoplasmic hybrids, formed by combining a nucleus from one species with the egg cytoplasm of another, have been used as one of the methods for breed improvement in aquaculture, but have been little exploited for developmental biology studies. Here, we used an artificial androgenesis technique to form nucleocytoplasmic hybrids comprising a goldfish haploid nucleus and loach egg cytoplasm. These hybrids were used to investigate interactions between the nucleus and cytoplasm during embryonic development. Additionally, the developmental characteristics of embryonic cells of nucleocytoplasmic hybrids were examined in chimeras produced by transplantation of blastomeres into recipient loach or goldfish embryos. We found that the nucleocytoplasmic hybrids arrested at the dome stage of embryonic development and did not form any gastrula structures. The goosecoid (gsc) and no tail (ntl) genes were expressed normally before gastrulation in nucleocytoplasmic hybrids, similar to diploid loach. However, expression of the gsc and ntl genes was not maintained in nucleocytoplasmic hybrids. In chimeric embryos, blastomeres derived from nucleocytoplasmic hybrids were found to mix with the cells of recipient loach embryos at the gastrula stage. The transplanted blastomeres formed small clusters at the somitogenesis stage and, finally, small spots at the hatching stage. In contrast, when the blastomeres were transplanted into goldfish embryos, the transplanted blastomeres aggregated in the chimeric embryos. Thus, embryonic cells from nucleocytoplasmic hybrids that arrest before gastrulation could survive beyond the somitogenesis stage depending on the cytoplasmic environment in the recipient embryos.

  17. Hybrid Baryons

    CERN Document Server

    Page, P R

    2003-01-01

    We review the status of hybrid baryons. The only known way to study hybrids rigorously is via excited adiabatic potentials. Hybrids can be modelled by both the bag and flux-tube models. The low-lying hybrid baryon is N 1/2^+ with a mass of 1.5-1.8 GeV. Hybrid baryons can be produced in the glue-rich processes of diffractive gamma N and pi N production, Psi decays and p pbar annihilation.

  18. Research Update: Challenges for high-efficiency hybrid lead-halide perovskite LEDs and the path towards electrically pumped lasing

    Science.gov (United States)

    Li, Guangru; Price, Michael; Deschler, Felix

    2016-09-01

    Hybrid lead-halide perovskites have emerged as promising solution-processed semiconductor materials for thin-film optoelectronics. In this review, we discuss current challenges in perovskite LED performance, using thin-film and nano-crystalline perovskite as emitter layers, and look at device performance and stability. Fabrication of electrically pumped, optical-feedback devices with hybrid lead halide perovskites as gain medium is a future challenge, initiated by the demonstration of optically pumped lasing structures with low gain thresholds. We explain the material parameters affecting optical gain in perovskites and discuss the challenges towards electrically pumped perovskite lasers.

  19. Research Update: Challenges for high-efficiency hybrid lead-halide perovskite LEDs and the path towards electrically pumped lasing

    Directory of Open Access Journals (Sweden)

    Guangru Li

    2016-09-01

    Full Text Available Hybrid lead-halide perovskites have emerged as promising solution-processed semiconductor materials for thin-film optoelectronics. In this review, we discuss current challenges in perovskite LED performance, using thin-film and nano-crystalline perovskite as emitter layers, and look at device performance and stability. Fabrication of electrically pumped, optical-feedback devices with hybrid lead halide perovskites as gain medium is a future challenge, initiated by the demonstration of optically pumped lasing structures with low gain thresholds. We explain the material parameters affecting optical gain in perovskites and discuss the challenges towards electrically pumped perovskite lasers.

  20. Research related to improved computer aided design software package. [comparative efficiency of finite, boundary, and hybrid element methods in elastostatics

    Science.gov (United States)

    Walston, W. H., Jr.

    1986-01-01

    The comparative computational efficiencies of the finite element (FEM), boundary element (BEM), and hybrid boundary element-finite element (HVFEM) analysis techniques are evaluated for representative bounded domain interior and unbounded domain exterior problems in elastostatics. Computational efficiency is carefully defined in this study as the computer time required to attain a specified level of solution accuracy. The study found the FEM superior to the BEM for the interior problem, while the reverse was true for the exterior problem. The hybrid analysis technique was found to be comparable or superior to both the FEM and BEM for both the interior and exterior problems.

  1. Interface design recommendations for computerised clinical audit and feedback: Hybrid usability evidence from a research-led system.

    Science.gov (United States)

    Brown, Benjamin; Balatsoukas, Panos; Williams, Richard; Sperrin, Matthew; Buchan, Iain

    2016-10-01

    Audit and Feedback (A&F) is a widely used quality improvement technique that measures clinicians' clinical performance and reports it back to them. Computerised A&F (e-A&F) system interfaces may consist of four key components: (1) Summaries of clinical performance; (2) Patient lists; (3) Patient-level data; (4) Recommended actions. There is a lack of evidence regarding how to best design e-A&F interfaces; establishing such evidence is key to maximising usability, and in turn improving patient safety. To evaluate the usability of a novel theoretically-informed and research-led e-A&F system for primary care (the Performance Improvement plaN GeneratoR: PINGR). (1) Describe PINGR's design, rationale and theoretical basis; (2) Identify usability issues with PINGR; (3) Understand how these issues may interfere with the cognitive goals of end-users; (4) Translate the issues into recommendations for the user-centred design of e-A&F systems. Eight experienced health system evaluators performed a usability inspection using an innovative hybrid approach consisting of five stages: (1) Development of representative user tasks, Goals, and Actions; (2) Combining Heuristic Evaluation and Cognitive Walkthrough methods into a single protocol to identify usability issues; (3) Consolidation of issues; (4) Severity rating of consolidated issues; (5) Analysis of issues according to usability heuristics, interface components, and Goal-Action structure. A final list of 47 issues were categorised into 8 heuristic themes. The most error-prone heuristics were 'Consistency and standards' (13 usability issues; 28% of the total) and 'Match between system and real world' (n=10, 21%). The recommended actions component of the PINGR interface had the most usability issues (n=21, 45%), followed by patient-level data (n=5, 11%), patient lists (n=4, 9%), and summaries of clinical performance (n=4, 9%). The most error-prone Actions across all user Goals were: (1) Patient selection from a list; (2) Data

  2. Ways of Developing Plants in Interspecific Hybridization of Cotton

    Institute of Scientific and Technical Information of China (English)

    RAKHMANKULOV; S; DAMINOVA; D; RAKHMANKULOV; M

    2008-01-01

    It is known,that there are various barriers to fertilization,development of embryos,and endosperm because of different number of chromosomes in parents in the interspecific hybridization of cotton.Thus the factors providing normal cell fission of a germ and endosperm are necessary.It is necessary to culture embryos in vitro on the artificial environments containing various phytohormones,or to

  3. Separation of an anterior inducing activity from development of dorsal axial mesoderm in large-headed frog embryos.

    Science.gov (United States)

    Elinson, R P

    1991-05-01

    The body of a vertebrate arises through a series of inductive interactions in the embryo. Macrocephaly is a distortion of the body in which a disproportionate amount of tissue is devoted to the head. This syndrome occurs in certain hybrids between frog species and appears to be due to an alteration of inductive relationships. Chimeric blastulae between normal and hybrid embryos developed macrocephaly when the marginal zone was derived from the hybrid. In these cases, a large cement gland, characteristic of the hybrid head, was induced to form from normal ectoderm. When hybrid zygotes were irradiated with ultraviolet (uv) light, all dorsoanterior structures, including notochord, somites, and central nervous system, were eliminated, but the most anterior-induced structure, the cement gland, remained. Embryos without dorsoanterior structures but with cement glands were also produced by injecting germinal vesicle extracts into the blastocoel of uv-irradiated nonhybrid embryos. These results demonstrate that an anterior inducing activity can be uncoupled from development of the neural tube and dorsal axial mesoderm.

  4. STUDY REGARDING THE LIGHT INFLUENCES ON EMBRYO DEVELOPMENT IN ZEBRA FISH (Danio rerio

    Directory of Open Access Journals (Sweden)

    MIHAELA BĂDILIŢĂ

    2013-12-01

    Full Text Available The aim of this paper is to emphasize the main aspects of the ways in which lightinfluences the development of zebra fish (Danio rerio embryos.During the experiments 3 variants with natural light, continuous light and totally darkwere used to monitor the development of zebra fish embryos in 40 ml Nunk culturedishes at optimum density (1 embryo/ 3 ml and at 28,5oC temperature.It could be noticed that most embryos died in continuous light medium (57%. Thismeans that such mediums are not suitable to embryos’ development. For the controlvariant (natural light it was recorded the lowest mortality rate of only 17% and intotally dark variant the mortality was of 40%.Researches on the influence of light on zebra fish embryo development showed that themost suited medium for supporting, growing and developing the Danio rerio embryosit the medium having natural light.

  5. Embryo culture in teratological surveillance and serum proteins in development. Progress report, 1979-1980

    Energy Technology Data Exchange (ETDEWEB)

    Klein, N.W.

    1980-07-01

    Research progress for the period 1979-1980 is reported. The feasibility of using rat embryo cultures to test the teratogenic activity of serum was studied. The mechanisms regulating the synthesis of serum proteins were investigated. (ACR)

  6. Relationship Between Morphology, Euploidy and Implantation Potential of Cleavage and Blastocyst Stage Embryos

    Directory of Open Access Journals (Sweden)

    Gaurav Majumdar

    2017-01-01

    Full Text Available Aim: The aim of this study was to investigate the relationship between the morphology, euploidy and implantation rate of cleavage stage and blastocyst stage embryos. Setting: Institution-based, tertiary care in-vitro fertilization centre. Study Design: This study included a retrospective data analysis of 306 embryos: 154 cleavage stage embryos and 152 blastocysts that underwent biopsy on day 3 and day 5/6, respectively, which were subsequently screened for aneuploidy by array comparative genomic hybridization analysis. Materials and Methods: Both cleavage stage and blastocyst stage embryos were categorized according to their morphology into the following three groups: good, average and poor. In addition, blastocysts were categorized into day 5 and day 6 embryos on the basis of their developmental rate. Results: The euploidy rate was found to be significantly higher for blastocysts with good morphology as compared to those with poor morphology, with 73.2, 50 and 40.5% euploid embryos in the good, average and poor morphology groups, respectively (P = 0.001. No significant association was found between day 3 embryo morphology and euploidy rates with 40.6, 29.3 and 25.8% euploid embryos in the three groups, respectively (P = 0.254. The implantation rates, as per morphology, for the transferred euploid cleavage stage and blastocyst stage embryos were 43.8, 37.5 and 0% (P = 0.354 and 51.7, 71.4 and 66.7% (P = 0.562 in the good, average and poor morphology groups, respectively. The euploidy rate for day 5 blastocysts was significantly higher (70% vs. 34.1%, P < 0.001 than that of day 6 blastocysts, but the implantation rate was similar in both the groups (58.8 and 50%, respectively. The miscarriage rates for the euploid cleavage stage and the blastocysts stage embryos were 18.2 and 8.3% (P = 0.575, respectively. Conclusion: Blastocyst morphology and the rate of development were found to be significantly associated with euploidy

  7. Bessel beam fluorescence lifetime tomography of live embryos (Conference Presentation)

    Science.gov (United States)

    Xu, Dongli; Peng, Leilei

    2016-03-01

    Optical tomography allows isotropic 3D imaging of embryos. Scanning-laser optical tomography (SLOT) has superior light collecting efficiency than wide-field optical tomography, making it ideal for fluorescence imaging of live embryos. We previously reported an imaging system that combines SLOT with a novel Fourier-multiplexed fluorescence lifetime imaging (FmFLIM) technique named FmFLIM-SLOT. FmFLIM-SLOT performs multiplexed FLIM-FRET readout of multiple FRET sensors in live embryos. Here we report a recent effort on improving the spatial resolution of the FmFLIM-SLOT system in order to image complex biochemical processes in live embryos at the cellular level. Optical tomography has to compromise between resolution and the depth of view. In SLOT, the commonly-used focused Gaussian beam diverges quickly from the focal plane, making it impossible to achieve high resolution imaging in a large volume specimen. We thus introduce Bessel beam laser-scanning tomography, which illuminates the sample with a spatial-light-modulator-generated Bessel beam that has an extended focal depth. The Bessel beam is scanned across the whole specimen. Fluorescence projection images are acquired at equal angular intervals as the sample rotates. Reconstruction artifacts due to annular-rings of the Bessel beam are removed by a modified 3D filtered back projection algorithm. Furthermore, in combination of Fourier-multiplexing fluorescence lifetime imaging (FmFLIM) method, the Bessel FmFLIM-SLOT system is capable of perform 3D lifetime imaging of live embryos at cellular resolution. The system is applied to in-vivo imaging of transgenic Zebrafish embryos. Results prove that Bessel FmFLIM-SLOT is a promising imaging method in development biology research.

  8. Rhesus monkey embryos produced by nuclear transfer from embryonic blastomeres or somatic cells.

    Science.gov (United States)

    Mitalipov, Shoukhrat M; Yeoman, Richard R; Nusser, Kevin D; Wolf, Don P

    2002-05-01

    Production of genetically identical nonhuman primates would reduce the number of animals required for biomedical research and dramatically impact studies pertaining to immune system function, such as development of the human-immunodeficiency-virus vaccine. Our long-term goal is to develop robust somatic cell cloning and/or twinning protocols in the rhesus macaque. The objective of this study was to determine the developmental competence of nuclear transfer (NT) embryos derived from embryonic blastomeres (embryonic cell NT) or fetal fibroblasts (somatic cell NT) as a first step in the production of rhesus monkeys by somatic cell cloning. Development of cleaved embryos up to the 8-cell stage was similar among embryonic and somatic cell NT embryos and comparable to controls created by intracytoplasmic sperm injection (ICSI; mean +/- SEM, 81 +/- 5%, 88 +/- 7%, and 87 +/- 4%, respectively). However, significantly lower rates of development to the blastocyst stage were observed with somatic cell NT embryos (1%) in contrast to embryonic cell NT (34 +/- 15%) or ICSI control embryos (46 +/- 6%). Development of somatic cell NT embryos was not markedly affected by donor cell treatment, timing of activation, or chemical activation protocol. Transfer of embryonic, but not of somatic cell NT embryos, into recipients resulted in term pregnancy. Future efforts will focus on optimizing the production of somatic cell NT embryos that develop in high efficiency to the blastocyst stage in vitro.

  9. Accurate and Phenol Free DNA Sexing of Day 30 Porcine Embryos by PCR.

    Science.gov (United States)

    Blanes, Milena S; Tsoi, Stephen C M; Dyck, Michael K

    2016-02-14

    Research into prenatal programming in the pig has shown that the sex of the developing embryo or fetus can influence the developmental outcome. Therefore, the ability to determine an embryo's sex is necessary in many experiments particularly regarding early development. The present protocol demonstrates an inexpensive, rapid and non-toxic preparation of pig genomic DNA for use with PCR. Day 30 embryos must be humanely collected according to the guidelines established by Institutional Animal Policy and Welfare Committees for the present protocol. The preparation of the whole embryo for this PCR based sexing technique simply involves grinding the frozen embryo to a fine powder using a pre-chilled mortar and pestle. PCR-quality DNA is released from a small amount of embryo powder by applying a hot incubation in an alkaline lysis reagent. Next, the DNA solution is mixed with neutralization buffer and used directly for PCR. Two primer pairs are generated to detect specific sex determining region of the Y- chromosome (SRY) and ZFX region of the X- chromosome with high accuracy and specificity. The same protocol can be applied to other elongated embryos (Day 10 to Day 14) earlier than Day 30. Also, this protocol can be carried with 96-welled plates when screening a large number of embryos, making it feasible for automation and high-throughput sex typing.

  10. COMPARATIVE RESEARCHE REGARDING METABOLIC PROFILE OF THE CALIFORNIAN, NEW ZEALAND WHITE, GRAND CHINCHILLA MEAT RABIT BREEDS AND THE F1 NZCH HYBRIDS

    Directory of Open Access Journals (Sweden)

    DANIELA-MARCELA TOBĂ (GOINA

    2013-12-01

    Full Text Available Precious biological characteristics of rabbits make their breeding a very profitable occupation. The rabbit meat, organoleptically same to the white meat, is rich in proteins, but low in fats. Biological researched done in direction to elucidate the biochemical systems that are the basis for organism physiological processes, have revealed that the level in which this process are develop directly influence the rabbits productivity capacity. 60 rabbit’s heads was used as biological material, distributed in: 15 Californian, 15 New Zeeland White, 15 Grand Chinchilla and 15 F1NZCH hybrids obtained from cross-breeding the New Zeeland White as maternal form and Grand Chinchilla as paternal form. Blood was sampled from the rabbit and was biochemical analyzed. The studied indices were: total protein, albumin, urea, uric acid, creatinine, total bilirubine, cholesterol, triglyceride and glucose. The experimental lot formed from F1 NZCH hybrids registered a concentration of 2.1 mg/dl uric acid, and in the other three lots the concentration was under 2 mg/dl. In all four lots, uric acid value was in normal limits. The determined creatinine registered very low values, under 1 mg/dl, at the low limit of reference values. At hybrids from New Zeeland White as maternal form and Grand Chinchilla as paternal form, in equal environmental conditions, the serum biochemical analysis haven’t registered significant differences compared to pure breeds individuals.

  11. Tiger, Bengal and Domestic Cat Embryos Produced by Homospecific and Interspecific Zona-Free Nuclear Transfer.

    Science.gov (United States)

    Moro, L N; Jarazo, J; Buemo, C; Hiriart, M I; Sestelo, A; Salamone, D F

    2015-10-01

    The aim of this study was to evaluate three different cloning strategies in the domestic cat (Felis silvestris) and to use the most efficient to generate wild felid embryos by interspecific cloning (iSCNT) using Bengal (a hybrid formed by the cross of Felis silvestris and Prionailurus bengalensis) and tiger (Panthera tigris) donor cells. In experiment 1, zona-free (ZP-free) cloning resulted in higher fusion and expanded blastocyst rates with respect to zona included cloning techniques that involved fusion or injection of the donor cell. In experiment 2, ZP-free iSCNT and embryo aggregation (2X) were assessed. Division velocity and blastocyst rates were increased by embryo aggregation in the three species. Despite fewer tiger embryos than Bengal and cat embryos reached the blastocyst stage, Tiger 2X group increased the percentage of blastocysts with respect to Tiger 1X group (3.2% vs 12.1%, respectively). Moreover, blastocyst cell number was almost duplicated in aggregated embryos with respect to non-aggregated ones within Bengal and tiger groups (278.3 ± 61.9 vs 516.8 ± 103.6 for Bengal 1X and Bengal 2X groups, respectively; 41 vs 220 ± 60 for Tiger 1X and Tiger 2X groups, respectively). OCT4 analysis also revealed that tiger blastocysts had higher proportion of OCT4-positive cells with respect to Bengal blastocysts and cat intracytoplasmic sperm injection blastocysts. In conclusion, ZP-free cloning has improved the quality of cat embryos with respect to the other cloning techniques evaluated and was successfully applied in iSCNT complemented with embryo aggregation.

  12. Characterization of a diverse secretome generated by the mouse preimplantation embryo in vitro

    Directory of Open Access Journals (Sweden)

    O'Neill Chris

    2010-06-01

    Full Text Available Abstract This study investigates the suitability of surface-enhanced laser desorption and ionization time-of-flight (SELDI-TOF and electrospray ionization (ESI mass spectrometry for analysis of the proteins released by the mouse preimplantation embryo in vitro. SELDI-TOF analysis with CM10 or IMAC30 (but not Q10 protein chips detected a protein peak at m/z ~8570 released by both C57BL6 and hybrid embryos. No other peaks unique to the presence of the embryo were identified with this method. ESI mass spectrometry of tryptic digests of embryo-conditioned media identified a total of 20 proteins released during development from the zygote to blastocyst stage. Four proteins were expressed in at least 7 out of 8 cultures tested, one of these (lactate dehydrogenase B was in all cultures. A further five proteins were in at least half of the cultures and 11 more proteins were in at least one culture. The expression of two of these proteins is essential for preimplantation embryo development (NLR family, pyrin domain containing 5 and peptidyl arginine deiminase, type VI. A further four proteins detected have roles in redox regulation of cells, and three others are capable of inducing post-translational modifications of proteins. This study shows the feasibility of ESI mass spectrometry for identifying the proteins secreted by the preimplantation embryo in vitro. This analysis identifies a range of targets that now require detailed functional analysis to assess whether their release by the embryo is an important property of early embryo development.

  13. In vitro embryo rescue culture of F1 progenies from crosses between different ploidy grapes.

    Science.gov (United States)

    Ji, W; Li, G R; Luo, Y X; Ma, X H; Wang, M; Ren, R

    2015-12-29

    Crossing different ploidy grapes is an effective way to obtain new seedless cultivars. Although embryo rescue has been extensively applied in breeding seedless and triploid grapes, only a few improved cultivars have been developed. Based on preliminary studies, we set five crosses between tetraploid and diploid grape varieties to obtain new hybrid triploid germplasms. Additionally, we compared two different methods of performing in vitro embryo rescue and sowing in the development of hybrid triploid grape plants. The results showed that the germination rate of hybrid seeds was much lower (0-22.8%) than that of the self-pollinated seeds (50.9-61.2%) obtained though the same method of in vitro culture. Meanwhile, the seed germination rates of all crosses obtain through in vitro culture (0-61.2%) were higher than those obtained through sowing (0-42.0%). Identification of ploidy level confirmed that three lines obtained from the crosses of 'Ruby Seedless (2x) x Black Olympia (4x)' and 'Big black (2x) x Kyoho (4x)' were triploid, and one line from the cross of 'Big black (2x) x Kyoho (4x)' was haploid, and the others were diploid, tetraploid, or aneuploidy plants. Moreover, 4 haploid and 42 triploid surviving grape seedlings were planted in a vineyard after propagation. Therefore, an efficient system of breeding triploid seedless grapes using embryo rescue was established and 42 hybrid triploid germplasms were obtained for use in future studies.

  14. Enhance beef cattle improvement by embryo biotechnologies.

    Science.gov (United States)

    Wu, B; Zan, L

    2012-10-01

    Embryo biotechnology has become one of the prominent high businesses worldwide. This technology has evolved through three major changes, that is, traditional embryo transfer (in vivo embryo production by donor superovulation), in vitro embryo production by ovum pick up with in vitro fertilization and notably current cloning technique by somatic cell nuclear transfer and transgenic animal production. Embryo biotechnology has widely been used in dairy and beef cattle industry and commercial bovine embryo transfer has become a large international business. Currently, many developed biotechnologies during the period from early oocyte stage to pre-implantation embryos can be used to create new animal breeds and accelerate genetic progression. Based on recent advances in embryo biotechnologies and authors current studies, this review will focus on a description of the application of this technology to beef cattle improvement and discuss how to use this technology to accelerate beef cattle breeding and production. The main topics of this presentation include the following: (i) how to increase calf production numbers from gametes including sperm and oocyte; (ii) multiple ovulation and embryo transfer breeding schemes; (iii) in vitro fertilization and intracytoplasm sperm injection in bovine; (iv) pronuclear development and transgenic animals; (v) sex selection from sperm and embryos; (vi) cloning and androgenesis; (vii) blastocyst development and embryonic stem cells; (viii) preservation of beef cattle genetic resources; and (ix) conclusions. © 2011 Blackwell Verlag GmbH.

  15. Aberrant DNA methylation in cloned ovine embryos

    Institute of Scientific and Technical Information of China (English)

    LIU Lei; HOU Jian; LEI TingHua; BAI JiaHua; GUAN Hong; AN XiaoRong

    2008-01-01

    By using the approach of immunofluorescence staining with an antibody against 5-methylcytosine (5MeC), the present study detected the DNA methylation patterns of cloned ovine embryos. The em-bryos derived from in vitro fertilization were also examined for reference purpose. The results showed that: (1) during the pre-implantation development, cloned embryos displayed a similar demethylation profile to the fertilized embryos; that is, the methylation level decreased to the lowest at 8-cell stage, and then increased again at morulae stage. However, methylation level was obviously higher in cloned embryos than in stage-matched fertilized embryos, especially at 8-cell stage and afterwards; (2) at blastocyst stage, the methylation pattern in cloned embryos was different from that in fertilized em-bryos. In cloned blastocyst, inner cell mass (ICM) exhibited a comparable level to trophectoderm cells (TE), while in in-vitro fertilized blastocyst the methylation level of ICM was lower than that of TE, which is not consistent with that reported by other authors. These results indicate that DNA methylation is abnormally reprogrammed in cloned embryos, implying that aberrant DNA methylation reprogramming may be one of the factors causing cloned embryos developmental failure.

  16. Embryo donation in Iran: an ethical review.

    Science.gov (United States)

    Afshar, Leila; Bagheri, Alireza

    2013-12-01

    Iran is the only Muslim country that has legislation on embryo donation, adopted in 2003. With an estimated 10-15% of couples in the country that are infertile, there are not any legal or religious barriers that prohibit an infertile couple from taking advantage of Assisted Reproductive Technologies (ARTs). Although all forms of ARTs available in Iran have been legitimized by religious authorities, there is a lack of legislation in all ARTs except embryo donation. By highlighting ethical issues in embryo donation, the paper presents a critical review of the Act of Embryo Donation in Iran. The paper argues that the Act does not provide enough safeguards for the future child and assurance for the safety of the donated embryos. It also does not restrict embryo donation to surplus embryos from infertile couples and is silent about the number of embryos that could be donated by each couple as well as the number of recipients for donated embryos by a couple. The Act is also silent about the issues of genetic linkage (nasab) and heritage which are challenging issues, especially in a conservative Islamic society. As a result, the future child may not inherit from their birth parents, as it is not required by the Act, or from the genetically related parents under the anonymity policy. Finally there is no standard national protocol or guidelines to evaluate the safety of the donated embryos. The paper concludes that despite its benefits, the Act lacks clarity, and it is subject to misunderstanding and confusion.

  17. Research on the filtering characteristic of single phase series hybrid active power filter based on fundamental magnetic flux compensation

    Science.gov (United States)

    Tian, Jun; Chen, Qiaofu; Zhang, Yuqi

    2012-12-01

    In this article, the PWM inverter works as a controlled fundamental current source in the single phase series hybrid active power filter (APF) based on fundamental magnetic flux compensation (FMFC). The series transformer can exhibit the self-impedance of primary winding to harmonic current, which forces harmonic current to flow into passive power filter. With the influence of harmonic current, the voltage of primary winding of transformer is a harmonic voltage, which makes the inverter output currents have a certain harmonic component, and it degrades the filtering characteristics. On the basis of PWM inverter, the mathematical model of series hybrid APF is established, and the filtering characteristics of single phase APF are analysed in detail. Three methods are gained to improve filtering characteristics: reasonably designing the inverter output filter inductance, increasing series transformer ratio and adopting voltage feed-forward control. Experimental results show that the proposed APF has greater validity.

  18. Research on a Novel Exciting Method for a Sandwich Transducer Operating in Longitudinal-Bending Hybrid Modes.

    Science.gov (United States)

    Liu, Yingxiang; Shen, Qiangqiang; Shi, Shengjun; Deng, Jie; Chen, Weishan; Wang, Liang

    2017-06-27

    A novel exciting method for a sandwich type piezoelectric transducer operating in longitudinal-bending hybrid vibration modes is proposed and discussed, in which the piezoelectric elements for the excitations of the longitudinal and bending vibrations share the same axial location, but correspond to different partitions. Whole-piece type piezoelectric plates with three separated partitions are used, in which the center partitions generate the first longitudinal vibration, while the upper and lower partitions produce the second bending vibration. Detailed comparisons between the proposed exciting method and the traditional one were accomplished by finite element method (FEM) calculations, which were further verified by experiments. Compared with the traditional exciting method using independent longitudinal ceramics and bending ceramics, the proposed method achieves higher electromechanical coupling factors and larger vibration amplitudes, especially for the bending vibration mode. This novel exciting method for longitudinal-bending hybrid vibrations has not changed the structural dimensions of the sandwich transducer, but markedly improves the mechanical output ability, which makes it very helpful and meaningful in designing new piezoelectric actuators operated in longitudinal-bending hybrid vibration modes.

  19. Cardiac hybrid imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gaemperli, Oliver [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); University Hospital Zurich, Nuclear Cardiology, Cardiovascular Center, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland)

    2014-05-15

    Hybrid cardiac single photon emission computed tomography (SPECT)/CT imaging allows combined assessment of anatomical and functional aspects of cardiac disease. In coronary artery disease (CAD), hybrid SPECT/CT imaging allows detection of coronary artery stenosis and myocardial perfusion abnormalities. The clinical value of hybrid imaging has been documented in several subsets of patients. In selected groups of patients, hybrid imaging improves the diagnostic accuracy to detect CAD compared to the single imaging techniques. Additionally, this approach facilitates functional interrogation of coronary stenoses and guidance with regard to revascularization procedures. Moreover, the anatomical information obtained from CT coronary angiography or coronary artery calcium scores (CACS) adds prognostic information over perfusion data from SPECT. The use of cardiac hybrid imaging has been favoured by the dissemination of dedicated hybrid systems and the release of dedicated image fusion software, which allow simple patient throughput for hybrid SPECT/CT studies. Further technological improvements such as more efficient detector technology to allow for low-radiation protocols, ultra-fast image acquisition and improved low-noise image reconstruction algorithms will be instrumental to further promote hybrid SPECT/CT in research and clinical practice. (orig.)

  20. Stolen twin: fascination and curiosity/twin research reports: evolution of sleep length; dental treatment of craniopagus twins; cryopreserved double embryo transfer; gender options in multiple pregnancy/current events: appendectomy in one twin; autistic twin marathon runners; 3D facial recognition; twin biathletes.

    Science.gov (United States)

    Segal, Nancy L

    2014-02-01

    The story of her allegedly stolen twin brother in Armenia is recounted by a 'singleton twin' living in the United States. The behavioral consequences and societal implications of this loss are considered. This case is followed by twin research reports on the evolution of sleep length, dental treatment of craniopagus conjoined twins, cryopreserved double embryo transfer (DET), and gender options in multiple pregnancy. Current events include the diagnosis of appendectomy in one identical twin, the accomplishments of autistic twin marathon runners, the power of three-dimensional (3D) facial recognition, and the goals of twin biathletes heading to the 2014 Sochi Olympics in Russia.

  1. [Transfer of genetic constructions through the transplacental barrier into mice embryos].

    Science.gov (United States)

    Efremov, A M; Buglaeva, A O; Orlov, S V; Burov, S V; Ignatovich, I A; Dizhe, E B; Shavva, V S; Perevozchikov, A P

    2010-01-01

    Genetic modification of mammalian embryos is an important way to model various changes in human development; also, it is an instrument for studying the functions of certain genes in mammals. Using our own experience in developing modes of delivery of genetic constructions to mammals in a nonviral way, we present here data on the delivery of a eukaryotic expression vector to mice embryos through the transplacental barrier with the use of hydrodynamic intravenous injections of DNA-hybrid peptide complexes to pregnant females. The peptide has a cationic part for interaction with DNA and includes a ligand structure towards receptors of the releasing factor of luteinizing hormone (RFLH, luliberin). Advantages of the suggested method are simplicity, economy, nonimmunogenicity for females, and the ability to multiply repeat the procedure. On the basis of the method, systemic gene delivery into tissues of mammalian embryos may be developed.

  2. Nucleolar remodeling in nuclear transfer embryos

    DEFF Research Database (Denmark)

    Laurincik, Jozef; Maddox-Hyttel, Poul

    2007-01-01

    the developmental potential of embryos originating from varied nuclear transfer protocols. In bovine in vivo developed embryos, functional ribosome-synthesizing nucleoli become structurally distinct toward the end of the 4th post-fertilization cell cycle. In embryonic cell nuclear transfer embryos, fully developed...... nucleoli are not apparent until the 5th cell cycle, whereas in somatic cell nuclear transfer embryos the functional nucleoli emerge already during the 3rd cell cycle. Intergeneric reconstructed embryos produced by the fusion of bovine differentiated somatic cell to a nonactivated ovine cytoplast fail...... is completed toward the end of the 4th cell cycle. A substantial proportion of bovine embryos produced by nuclear transfer of embryonic or somatic cells to bovine ooplasts display aberrations in protein localization in one or more blastomers. This information is indicative of underlying aberrations in genomic...

  3. Nucleolar remodeling in nuclear transfer embryos

    DEFF Research Database (Denmark)

    Laurincik, Jozef; Maddox-Hyttel, Poul

    2007-01-01

    nucleoli are not apparent until the 5th cell cycle, whereas in somatic cell nuclear transfer embryos the functional nucleoli emerge already during the 3rd cell cycle. Intergeneric reconstructed embryos produced by the fusion of bovine differentiated somatic cell to a nonactivated ovine cytoplast fail...... the developmental potential of embryos originating from varied nuclear transfer protocols. In bovine in vivo developed embryos, functional ribosome-synthesizing nucleoli become structurally distinct toward the end of the 4th post-fertilization cell cycle. In embryonic cell nuclear transfer embryos, fully developed...... is completed toward the end of the 4th cell cycle. A substantial proportion of bovine embryos produced by nuclear transfer of embryonic or somatic cells to bovine ooplasts display aberrations in protein localization in one or more blastomers. This information is indicative of underlying aberrations in genomic...

  4. Nucleolar remodeling in nuclear transfer embryos

    DEFF Research Database (Denmark)

    Laurincik, Jozef; Maddox-Hyttel, Poul

    2007-01-01

    nucleoli are not apparent until the 5th cell cycle, whereas in somatic cell nuclear transfer embryos the functional nucleoli emerge already during the 3rd cell cycle. Intergeneric reconstructed embryos produced by the fusion of bovine differentiated somatic cell to a nonactivated ovine cytoplast fail...... the developmental potential of embryos originating from varied nuclear transfer protocols. In bovine in vivo developed embryos, functional ribosome-synthesizing nucleoli become structurally distinct toward the end of the 4th post-fertilization cell cycle. In embryonic cell nuclear transfer embryos, fully developed...... is completed toward the end of the 4th cell cycle. A substantial proportion of bovine embryos produced by nuclear transfer of embryonic or somatic cells to bovine ooplasts display aberrations in protein localization in one or more blastomers. This information is indicative of underlying aberrations in genomic...

  5. Hybrid systems with constraints

    CERN Document Server

    Daafouz, Jamal; Sigalotti, Mario

    2013-01-01

    Control theory is the main subject of this title, in particular analysis and control design for hybrid dynamic systems.The notion of hybrid systems offers a strong theoretical and unified framework to cope with the modeling, analysis and control design of systems where both continuous and discrete dynamics interact. The theory of hybrid systems has been the subject of intensive research over the last decade and a large number of diverse and challenging problems have been investigated. Nevertheless, many important mathematical problems remain open.This book is dedicated mainly to

  6. Hybrid silicon evanescent devices

    Directory of Open Access Journals (Sweden)

    Alexander W. Fang

    2007-07-01

    Full Text Available Si photonics as an integration platform has recently been a focus of optoelectronics research because of the promise of low-cost manufacturing based on the ubiquitous electronics fabrication infrastructure. The key challenge for Si photonic systems is the realization of compact, electrically driven optical gain elements. We review our recent developments in hybrid Si evanescent devices. We have demonstrated electrically pumped lasers, amplifiers, and photodetectors that can provide a low-cost, scalable solution for hybrid integration on a Si platform by using a novel hybrid waveguide architecture, consisting of III-V quantum wells bonded to Si waveguides.

  7. Hybrid vehicles

    Energy Technology Data Exchange (ETDEWEB)

    West, J.G.W. [Electrical Machines (United Kingdom)

    1997-07-01

    The reasons for adopting hybrid vehicles result mainly from the lack of adequate range from electric vehicles at an acceptable cost. Hybrids can offer significant improvements in emissions and fuel economy. Series and parallel hybrids are compared. A combination of series and parallel operation would be the ideal. This can be obtained using a planetary gearbox as a power split device allowing a small generator to transfer power to the propulsion motor giving the effect of a CVT. It allows the engine to run at semi-constant speed giving better fuel economy and reduced emissions. Hybrid car developments are described that show the wide range of possible hybrid systems. (author)

  8. Embryo forming cells in carrot suspension cultures.

    OpenAIRE

    Toonen, M.A.J.

    1997-01-01

    Somatic cells of many plant species can be cultured in vitro and induced to form embryos that are able to develop into mature plants. This process, termed somatic embryogenesis, was originally described in carrot (Daucus carota L.). Somatic embryos develop through the same characteristic morphological stages, i.e. the globular-, heartand torpedo-stage respectively, as their zygotic counterparts. Due to the different cellular origin of somatic embryos, it is less clear to what extent the earli...

  9. Facial Transplants in Xenopus laevis Embryos

    OpenAIRE

    Jacox, Laura A.; Dickinson, Amanda J.; Sive, Hazel

    2014-01-01

    Craniofacial birth defects occur in 1 out of every 700 live births, but etiology is rarely known due to limited understanding of craniofacial development. To identify where signaling pathways and tissues act during patterning of the developing face, a 'face transplant' technique has been developed in embryos of the frog Xenopus laevis. A region of presumptive facial tissue (the "Extreme Anterior Domain" (EAD)) is removed from a donor embryo at tailbud stage, and transplanted to a host embryo ...

  10. 9 CFR 98.16 - The embryo collection unit.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false The embryo collection unit. 98.16... CERTAIN ANIMAL EMBRYOS AND ANIMAL SEMEN Ruminant and Swine Embryos From Regions Where Rinderpest or Foot-and-Mouth Disease Exists § 98.16 The embryo collection unit. Ruminant and swine embryos may...

  11. Influence of carbon nanotube length on toxicity to zebrafish embryos

    Directory of Open Access Journals (Sweden)

    Cheng J

    2012-07-01

    Full Text Available Jinping Cheng,1,2 Shuk Han Cheng11Department of Biology and Chemistry, City University of Hong Kong, Hong Kong; 2State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, ChinaAbstract: There is currently a large difference of opinion in nanotoxicology studies of nanomaterials. There is concern about why some studies have indicated that there is strong toxicity, while others have not. In this study, the length of carbon nanotubes greatly affected their toxicity in zebrafish embryos. Multiwalled carbon nanotubes (MWCNTs were sonicated in a nitric acid solution for 24 hours and 48 hours. The modified MWCNTs were tested in early developing zebrafish embryo. MWCNTs prepared with the longer sonication time resulted in severe developmental toxicity; however, the shorter sonication time did not induce any obvious toxicity in the tested developing zebrafish embryos. The cellular and molecular changes of the affected zebrafish embryos were studied and the observed phenotypes scored. This study suggests that length plays an important role in the in vivo toxicity of functionalized CNTs. This study will help in furthering the understanding on current differences in toxicity studies of nanomaterials.Keywords: length, carbon nanotubes, sonication, developmental toxicity, zebrafish

  12. Proteomic analysis of zebrafish embryos exposed to simulated-microgravity

    Science.gov (United States)

    Hang, Xiaoming; Ma, Wenwen; Wang, Wei; Liu, Cong; Sun, Yeqing

    Microgravity can induce a serial of physiological and pathological changes in human body, such as cardiovascular functional disorder, bone loss, muscular atrophy and impaired immune system function, etc. In this research, we focus on the influence of microgravity to vertebrate embryo development. As a powerful model for studying vertebrate development, zebrafish embryos at 8 hpf (hour past fertilization) and 24 hpf were placed into a NASA developed bioreac-tor (RCCS) to simulate microgravity for 64 and 48 hours, respectively. The same number of control embryos from the same parents were placed in a tissue culture dish at the same temper-ature of 28° C. Each experiment was repeated 3 times and analyzed by two-dimensional (2-D) gel electrophoresis. Image analysis of silver stained 2-D gels revealed that 64 from total 292 protein spots showed quantitative and qualitative variations that were significantly (Pprotein spots with significant expression alteration (Pproteins, 3 down-regulated proteins were identified as bectin 2, centrosomal protein of 135kDa and tropomyosin 4, while the up-regulated protein was identified as creatine kinase muscle B. Other protein spots showed significant expression alteration will be identified successively and the corresponding genes expression will also be measured by Q-PCR method at different development stages. The data presented in this study illustrate that zebrafish embryo can be significantly induced by microgravity on the expression of proteins involved in bone and muscle formation. Key Words: Danio rerio; Simulated-microgravity; Proteomics

  13. Transmission OF Campylobacter coli in chicken embryos

    Science.gov (United States)

    Rossi, Daise Aparecida; Fonseca, Belchiolina Beatriz; de Melo, Roberta Torres; Felipe, Gutembergue da Silva; da Silva, Paulo Lourenço; Mendonça, Eliane Pereira; Filgueiras, Ana Luzia Lauria; Beletti, Marcelo Emilio

    2012-01-01

    Campylobacter coli is an important species involved in human cases of enteritis, and chickens are carriers of the pathogen mainly in developing country. The current study aimed to evaluate the transmission of C. coli and its pathogenic effects in chicken embryos. Breeder hens were inoculated intra-esophageally with C. coli isolated from chickens, and their eggs and embryos were analyzed for the presence of bacteria using real-time PCR and plate culture. The viability of embryos was verified. In parallel, SPF eggs were inoculated with C. coli in the air sac; after incubation, the embryos were submitted to the same analysis as the embryos from breeder hens. In embryos and fertile eggs from breeder hens, the bacterium was only identified by molecular methods; in the SPF eggs, however, the bacterium was detected by both techniques. The results showed no relationship between embryo mortality and positivity for C. coli in the embryos from breeder hens. However, the presence of bacteria is a cause of precocious mortality for SPF embryos. This study revealed that although the vertical transmission is a possible event, the bacteria can not grow in embryonic field samples. PMID:24031861

  14. Nano-nutrition of chicken embryos

    DEFF Research Database (Denmark)

    Sawosz, Filip; Pineda, Lane Manalili; Hotowy, Anna

    2013-01-01

    It has been suggested that the quantity and quality of nutrients stored in the egg might not be optimal for the fast rate of chicken embryo development in modern broilers, and embryos could be supplemented with nutrients by in ovo injection. Recent experiments showed that in ovo feeding reduces...... broiler eggs was randomly divided into a Control group without injection and injected groups with hydrocolloids of Nano-Ag, ATP or a complex of Nano-Ag and ATP (Nano-Ag/ATP). The embryos were evaluated on day 20 of incubation. The results indicate that the application of ATP to chicken embryos increases...

  15. Transmission of Campylobacter coli in chicken embryos

    Directory of Open Access Journals (Sweden)

    Daise Aparecida Rossi

    2012-06-01

    Full Text Available Campylobacter coli is an important species involved in human cases of enteritis, and chickens are carriers of the pathogen mainly in developing country. The current study aimed to evaluate the transmission of C. coli and its pathogenic effects in chicken embryos. Breeder hens were inoculated intra-esophageally with C. coli isolated from chickens, and their eggs and embryos were analyzed for the presence of bacteria using real-time PCR and plate culture. The viability of embryos was verified. In parallel, SPF eggs were inoculated with C. coli in the air sac; after incubation, the embryos were submitted to the same analysis as the embryos from breeder hens. In embryos and fertile eggs from breeder hens, the bacterium was only identified by molecular methods; in the SPF eggs, however, the bacterium was detected by both techniques. The results showed no relationship between embryo mortality and positivity for C. coli in the embryos from breeder hens. However, the presence of bacteria is a cause of precocious mortality for SPF embryos. This study revealed that although the vertical transmission is a possible event, the bacteria can not grow in embryonic field samples.

  16. Cytological mechanisms of interspecific incrossability and hybrid sterility between Oryza sativa L. and O.alta Swallen

    Institute of Scientific and Technical Information of China (English)

    FU XueLin; LU YongGen; LIU XiangDong; Li JinQuan; Feng JiuHuan

    2007-01-01

    Oryza sativa and O. alta belong to AA and CCDD genomes in Oryza, respectively. Interspecific reproductive isolation limits the transfer of favorable genes from O. alta into O. sativa. The cytological mechanisms of interspecific incrossability and hybrid sterility between O. sativa and O. alta were studied systematically in this paper. We indentified two cytological causes of interspecific incrossability. First, we observed embryo sac incompatibility that caused fertilization barriers of variable severity such as non-fertilization, fertilization stagnation and egg cell single-fertilization. Second, we observed hybrid inviability, the major cause for incrossability, apparent from hybrid embryo developmental stagnation and embryo abortion. Hybrid sterility included both embryo sac sterility and pollen sterility.The hybrid embryo sac was completely sterile and exhibited mainly embryo sac degeneration. Hybrid pollen was also sterile and mainly typical abortive. Hybrid sterility was mainly caused by severely abnormal meioses of megasporocytes and pollen mother cells; it is the most important abnormality, being chromosome sterility. Several methods are suggested to overcome the interspecific reproductive isolation between O. sativa and O. alta.

  17. High frequency somatic embryogenesis and plant regeneration from zygotic embryo-derived callus cultures of three Allium species

    NARCIS (Netherlands)

    Valk, P. van der; Scholten, O.E.; Verstappen, F.; Jansen, R.C.; Dons, J.J.M.

    1992-01-01

    The plant regeneration ability of zygotic embryo-derived callus cultures was studied for 12 A. cepa varieties and accessions, two A. fistulosum varieties, one A. fistulosum × A. cepa interspecific hybrid and two A. porrum varieties. Compact embryogenic callus was induced on Murashige and Skoog (MS)

  18. High frequency somatic embryogenesis and plant regeneration from zygotic embryo-derived callus cultures of three Allium species

    NARCIS (Netherlands)

    Valk, P. van der; Scholten, O.E.; Verstappen, F.; Jansen, R.C.; Dons, J.J.M.

    1992-01-01

    The plant regeneration ability of zygotic embryo-derived callus cultures was studied for 12 A. cepa varieties and accessions, two A. fistulosum varieties, one A. fistulosum × A. cepa interspecific hybrid and two A. porrum varieties. Compact embryogenic callus was induced on Murashige and Skoog (MS)

  19. Research Progress on Organic/Inorganic Hybrid Solar Cells%有机无机杂化太阳能电池的研究进展

    Institute of Scientific and Technical Information of China (English)

    冷明哲; 宋箭叶; 刘建强

    2013-01-01

    The structure and working mechanism of organic/inorganic hybrid solar cells, as well as the prepara tion method, are briefly introduced. The influence of the specific form of inorganic materials and types of organic mate rials on the integral transformation efficiency are reviewed,and the research progress on hybrid solar cells which per formance improved by other methods are discovered. The research direction of improvement of organic/inorganic hy brid battery performance is also pointed out.%概括介绍了有机无机杂化太阳能电池的结构、原理及制备方法,从无机材料的具体形态和有机材料种类的选择入手阐述其对电池整体转化效率的影响,探索了其他方法完善杂化电池性能的研究进展,指出了改进有机无机杂化太阳能电池性能的相关途径.

  20. The Hybrid Threat: Crime, Terrorism and Insurgency in Mexico. Proceedings of the Joint Policy and Research Forum

    Science.gov (United States)

    2011-12-01

    Foreword Frank J. Cilluffo and Bert B. Tussing THE HYBRID THREAT of crime, terrorism and insurgency is presently understudied as a matter of policy...brave men and women in Mexico – to include the media , local police, local mayors, business leaders – all of whom now stand on the edge. A Joint CSL...unnamed television media inquiry having to do with the situation on the border, by saying: “I’m sorry we can’t take you out there....We’re not allowed

  1. The impact of array genomic hybridization on mental retardation research: a review of current technologies and their clinical utility.

    Science.gov (United States)

    Zahir, F; Friedman, J M

    2007-10-01

    Our understanding of the causes of mental retardation is benefiting greatly from whole-genome scans to detect submicroscopic pathogenic copy number variants (CNVs) that are undetectable by conventional cytogenetic analysis. The current method of choice for performing whole-genome scans for CNVs is array genomic hybridization (AGH). Several platforms are available for AGH, each with its own strengths and limitations. This review discusses considerations that are relevant to the clinical use of whole-genome AGH platforms for the diagnosis of pathogenic CNVs in children with mental retardation. Whole-genome AGH studies are a maturing technology, but their high diagnostic utility assures their increasing use in clinical genetics.

  2. Legal Hybrids

    DEFF Research Database (Denmark)

    Herrmann, Janne Rothmar

    2009-01-01

    The article discusses the inadequacy of traditional theory on legal personhood in relation to embryos and foetuses. To challenge the somewhat binary view of legal personhood according to which the ‘born alive' criterion is paramount the article demonstrates that the number of legal categories...... in which embryos and foetuses are placed are much more complex. These categories are identified using Danish legislation as an example and on that basis the article extracts and identifies the different parameters that play a part in the legal categorisation of the human conceptus....

  3. Localization of HstI transcripts to the apical ectodermal ridge in the mouse embryo.

    Science.gov (United States)

    Suzuki, H R; Sakamoto, H; Yoshida, T; Sugimura, T; Terada, M; Solursh, M

    1992-03-01

    The HstI gene is a transforming gene, coding for a protein of the fibroblast growth factor family (Sakamoto et al., 1986). Previous RNA hybridization studies with the mouse homolog demonstrated the presence of a 3.0-kb transcript in Day 11 and 14 mouse embryos. Here we detect a 3.0-kb transcript in the limb and body of the dissected Day 11 mouse embryo. PCR amplification using HstI-specific primers also showed comparable results. In order to localize the HstI transcripts during development, corresponding HstI cDNA was isolated, and an HstI-specific region was used as a probe for in situ hybridization analysis. Serial sections of embryos from Day 8 (early-somite stages) through Days 9, 10, 11, and 12 of gestation were examined. With the antisense probe, a signal was detected in the Day 11 and 12 embryo, where it was localized to the apical ectodermal ridge (AER) of the limb bud. This structure is well known for its role in promoting the distal outgrowth of the developing limb bud. Signal was detected in both fore- and hindlimbs during the period of rapid distal growth. This restricted localization suggests a role for HstI in normal embryogenesis, including outgrowth of the limb bud.

  4. Research and Development of Hybrid Electric Vehicles CAN-Bus Data Monitor and Diagnostic System through OBD-II and Android-Based Smartphones

    Directory of Open Access Journals (Sweden)

    Yalian Yang

    2013-01-01

    Full Text Available With the rapid development of the smartphone market, future cars seem to have more connections with intelligent cell phone and Internet. Intelligent transportation system (ITS and telematics system have become research focus in recent years. There is an increasing demand for remote monitoring and diagnostic system as the further research of hybrid electric vehicle (HEV goes on. In this paper, a remote controller area network bus (CAN-Bus data monitor and diagnostic system for HEV is presented using on board diagnostic version-II (OBD-II and Android-based smartphone. It is low-cost, convenient, and extensible with smartphone used in the system to realize communication with ELM327 and remote monitoring center wirelessly. The prototype of client and server is developed in Java language, and it is proved by the test that the system works stably and the collected data have practical values.

  5. Conception and development of the Second Life® Embryo Physics Course.

    Science.gov (United States)

    Gordon, Richard

    2013-06-01

    The study of embryos with the tools and mindset of physics, started by Wilhelm His in the 1880s, has resumed after a hiatus of a century. The Embryo Physics Course convenes online allowing interested researchers and students, who are scattered around the world, to gather weekly in one place, the virtual world of Second Life®. It attracts people from a wide variety of disciplines and walks of life: applied mathematics, artificial life, bioengineering, biophysics, cancer biology, cellular automata, civil engineering, computer science, embryology, electrical engineering, evolution, finite element methods, history of biology, human genetics, mathematics, molecular developmental biology, molecular biology, nanotechnology, philosophy of biology, phycology, physics, self-reproducing systems, stem cells, tensegrity structures, theoretical biology, and tissue engineering. Now in its fifth year, the Embryo Physics Course provides a focus for research on the central question of how an embryo builds itself.

  6. Simulative Study into the Development of a Hybrid HVDC System Through a Comparative Research with HVAC: a Futuristic Approach

    Directory of Open Access Journals (Sweden)

    R. S. Narayan

    2017-06-01

    Full Text Available High Voltage Direct Current Transmission (HVDC is considered a better solution for bulk long distance transmissions. The increased use of HVDC is a result of its advantages over the HVAC systems and especially of its fault stability nature. A better solution is proposed by using a Voltage Source Controlled–HVDC as one of the infeed for the Multi-Infeed HVDC (MIDC or MI-HVDC systems. The main advantage with the VSC converter is its flexible power control which enhances the stability of the MIDC systems. In this paper, the behavior of an HVDC system is compared with that of an HVAC during faults. A Hybrid HVDC system that includes a LCC as a rectifier unit and a VSC converter as the inverter is being proposed. It is considered suitable for MIDC systems and particularly for supplying a weak AC system. The performance of the system during steady state and transient conditions for all the proposed topologies including HVDC, HVAC and Hybrid HVDC are studied in MATLAB/SIMULINK. All of the proposed control strategies are evaluated via a series of simulation case studies.

  7. Research on beam characteristics in a large-Fresnel-number unstable-waveguide hybrid resonator with parabolic mirrors.

    Science.gov (United States)

    Wang, Wei; Qin, Yingxiong; Xiao, Yu; Zhong, Lijing; Wu, Chao; Wang, Zhen; Wan, Wen; Tang, Xiahui

    2016-07-20

    Large-Fresnel-number unstable-waveguide hybrid resonators employing spherical resonator mirrors suffer from spherical aberration, which adversely affects beam quality and alignment sensitivity. In this paper, we present experimental and numerical wave-optics simulations of the beam characteristics of a negative-branch hybrid resonator having parabolic mirrors with a large equivalent Fresnel number in the unstable direction. These results are compared with a resonator using spherical mirrors. Using parabolic mirrors, the output beam has a smaller beam spot size and higher power density at the focal plane. We found that the power extraction efficiency is 3.5% higher when compared with a resonator using spherical mirrors as the cavity length was varied between -1 and 1 mm from the ideal confocal resonator. In addition, the power extraction efficiency is 5.6% higher for mirror tilt angles varied between -6 and 6 mrad. Furthermore, the output propagating field is similar to a converging wave for a spherical mirror resonator and the output beam direction deviates 3.5 mrad from the optical axis. The simulation results are in good agreement with the experimental results.

  8. Embryonic stem cells from blastomeres maintaining embryo viability.

    Science.gov (United States)

    Klimanskaya, Irina

    2013-01-01

    A wide variety of cell and tissue types that are sought in regenerative medicine can be generated from embryonic stem cells (ESCs), and currently two derivatives of human embryonic stem cells (hESCs) have entered human clinical trials. However, the ethical controversy surrounding this technology, which uses preimplantation human embryos to generate cell lines, is limiting research and the development of new therapies. Several new technologies such as induced pluripotent cells or parthenogenetically derived pluripotent cells hold great promise, but more research is needed before their derivatives can be proven to be safe and functional for use in human patients. The blastomere biopsy-based technique allows the derivation of human ESClines without sacrificing a human embryo and was shown to be robust and produce safe and functional derivatives of therapeutic value.

  9. Research and development on power coupling device of hybrid electric tractor%混合动力拖拉机动力耦合装置的研制

    Institute of Scientific and Technical Information of China (English)

    邓晓亭; 朱思洪; 钱忠祥; 张莹

    2012-01-01

    近年来,农用车辆特别是拖拉机对环境和资源造成的压力逐年增大,开展节能环保拖拉机特别是混合动力拖拉机的研发已成为迫在眉睫的重要课题,而动力耦合装置是混合动力拖拉机的核心.该文根据拖拉机工作特性和传动特性要求,对混合动力拖拉机动力耦合装置传动比、特征参数和齿数匹配等进行了设计.根据传动载荷需求和制造工艺要求进行了结构设计和强度校核,研制了适用于并联式混合动力拖拉机的动力耦合装置.在自行搭建的混合动力拖拉机试验台上对该耦合装置进行了测试.试验结果表明,该装置能够满足拖拉机工作状态下的工作特性要求,输出端转速对动力源的转速变化很敏感,实时变化性能优,而输出端转矩对动力源转速变化不敏感.该耦合装置的研制为混合动力拖拉机的研发提供了基础.%In recent years, effects of agricultural vehicles, especially tractors on the environment and resources are increasing year by year, so carrying out the research and development of energy-conservation and environmental protection tractors, especially hybrid electric tractors has become the imminent important subject. And the power coupling is the core of hybrid electric drive system. According to the requirements of working properties and transmission characteristics of tractors, the transmission ratio, characteristic parameters and matching number of gear teeth of power coupling device for hybrid electric tractor were designed. Based on the requirement of transmission load and manufacturing technology, the structure design and strength check were processed. Then a new power coupling for parallel hybrid electric tractor was developed, which was also tested on self-developed hybrid electric tractor test-bed. The results showed that the power coupling device can meet the needs of working characteristic under working condition. In addition, the output speeds were

  10. Transformation of frog embryos with a rabbit beta-globin gene.

    OpenAIRE

    Rusconi, S; Schaffner, W

    1981-01-01

    In order to study the fate and possible expression of foreign DNA during embryogenesis of the frog Xenopus laevis, we have injected a rabbit beta-globin gene into fertilized Xenopus eggs. Frog embryo DNA was extracted at various stages of development, fractionated by agarose gel electrophoresis, transferred to nitrocellulose filters, and hybridized to labeled beta-globin recombinant plasmid DNA. It was found that the injected DNA replicated extrachromosomally, reaching, at gastrula stage, a l...

  11. Building the giant planet cores by convergent migration of pebble-accreting embryos

    Science.gov (United States)

    Chrenko, Ondrej; Broz, Miroslav

    2016-10-01

    An explanation of the accretion buildup of giant planet cores on rather short (~Myr) time scales remains a long-standing challenge for scenarios of planetary system formation. One of the recently proposed processes that can take part during this evolutionary stage is the convergent Type I migration of Earth-sized embryos towards the zero-torque radius, occurring at an opacity transition within the dusty-gaseous protoplanetary disk (e.g. Pierens et al. 2013). Inconveniently, simulations show that such groups of embryos do not merge easily because they often get locked in mutual mean-motion resonances and consequently form an inward-migrating convoy.We revise this possibility of merging embryos while taking into account their ongoing growth by pebble accretion. Our aim is to check whether the rapid changes of masses combined with the migration of embryos through the feeding zone can break the resonant chain and allow for the giant planet core formation.The environment of the protoplanetary disk is modeled with the 2D FARGO code (Masset 2000), which we modified in order to perform non-isothermal hydrodynamic simulations, assuming flux-limited radiative diffusion (Levermore & Pomraning 1981). The embedded massive bodies are evolved simultaneously in 3D using the hybrid Wisdom-Holman/Gauss-Radau integrator from the Rebound package (Rein & Spiegel 2015). A semi-analytic method is used to evolve the masses of embryos by pebble accretion (e.g. Levison et al. 2015).

  12. STUDIES REGARDING CULTURE MEDIUM INFLUENCE ON IN VITRO REGENERATION FROM WHEAT IMATURE EMBRYOS

    Directory of Open Access Journals (Sweden)

    M. DANCI

    2013-12-01

    Full Text Available Surnamed „embryos’ saving method”, embryos culture is an in vitro technique used for over half of the century for saving the distant hybridization products, that would have degenerate in other conditions. Immature embryos culture is used for initiation of in vitro cultures imposed by the impossibility of using other explants for some of the plant species. Wheat is one of the crops that immature embryos culture technique is suitable for. This methods principle is based on aseptic embryos excision and their inoculation to an adequate culture medium. In vitro culture results depend in a greater manner of the basic culture medium and the hormonal balance used. Immature embryos isolated from two Romanian wheat cultivars – Dropia and Lovrin 41 – were inoculated for callus production on two types of basic media added with 2,4 D. The selected calluses were transferred on MS basic medium and several parameters were registered. Both cultivars emphasized a good callusing capacity, in a different percentage depending on the culture media used, such as 71,09 – 94,45%.. big differences between the cultivars regarding embriogenic callus frequency, shooting callus frequency and regenerated plants percentage were registered.

  13. Overexpression of Fyn tyrosine kinase causes abnormal development of primary sensory neurons in Xenopus laevis embryos.

    Science.gov (United States)

    Saito, R; Fujita, N; Nagata, S

    2001-06-01

    The expression and function of the Src family protein tyrosine kinase Fyn in Xenopus laevis embryos have been examined. In situ hybridization analysis demonstrated nervous system-specific expression of Fyn mRNA in tail-bud embryos. However, a class of primary sensory neurons; that is, Rohon-Beard (RB) neurons, which is positive for immunoglobulin superfamily cell adhesion molecules (CAM), neural cell adhesion molecule (N-CAM) and contactin, is devoid of Fyn expression. Injection of Fyn mRNA into one of the blastomeres at the 2-cell stage led to overexpression of Fyn in the injected half of the tail-bud embryos. Immunolabeling of the embryos with anti-HNK-1 antibody revealed that the peripheral axons of RB neurons were partially misguided and bound to each other to form abnormal subcutaneous fascicles. Similar abnormality was induced by injection of the Fyn overexpression vector. The incidence of abnormality appeared dose-dependent, being 68-92% of the injected embryos at 50-400 pg of mRNA. Co-injection of the contactin antisense vector depleted contactin mRNA accumulation without affecting Fyn overexpression and reduced the incidence of the abnormal RB-cell phenotype. However, the N-CAM antisense was ineffective in reducing this abnormality. These results suggest that Fyn can modify signals regulating axonal guidance or fasciculation in the developing X. laevis nervous system and that contactin may affect this action of Fyn.

  14. Transcriptional Responses and Mechanisms of Copper-Induced Dysfunctional Locomotor Behavior in Zebrafish Embryos.

    Science.gov (United States)

    Zhang, Ting; Xu, Lian; Wu, Jun-Jie; Wang, Wei-Min; Mei, Jie; Ma, Xu-Fa; Liu, Jing-Xia

    2015-11-01

    Copper-induced delayed hatching and dysfunctional movement had been reported previously, and unbalanced free copper was found in the body of humans with Alzheimer's disease and other neural diseases, but details of the underlying mechanisms are still unknown. In this study, zebrafish (Danio rerio) embryos exposed to over 3.9 μM of copper-exhibited delayed hatching and significantly dysfunctional movement. Using high-throughput in situ hybridization screening and by conducting an in-depth analysis of gene characterization in embryos exposed to copper, we found that copper caused neural crest defects from the initiation stage of neurogenesis, and embryos younger than the 70% epiboly stage were sensitive to copper toxicity. The myelination of Schwann cells, other than melanophores, cartilage, and neurons, was inhibited by copper during neurogenesis. In addition, axon guidance was blocked by copper. Downregulated cdx4-hox might have contributed to the neurogenesis-related defects. Moreover, copper inhibited the differentiation of muscle fibers and myotomes but not the specification of muscle progenitors. In summary, our data reveal a novel molecular mechanism for copper-inhibited locomotor behavior in embryos, in which copper blocks functional muscle fiber specification during myogenesis and inhibits the specification of axons and Schwann cell myelination during neurogenesis. A combination of these processes results in dysfunctional locomotor behavior in zebrafish embryos exposed to copper. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  15. Developmental potential and behavior of tetraploid cells in the mouse embryo.

    Science.gov (United States)

    Eakin, Guy S; Hadjantonakis, Anna-Katerina; Papaioannou, Virginia E; Behringer, Richard R

    2005-12-01

    Tetraploid (4n) mouse embryos die at variable developmental stages. By examining 4n embryos from F2 hybrid and outbred mice, we show that 4n developmental potential is influenced by genetic background. The imprinted inactivation of an X chromosome-linked eGFP transgene in extraembryonic tissues occurred correctly in 4n embryos. A decrease of the cleavage rate in 4n preimplantation embryos compared to diploid (2n) embryos was revealed by real-time imaging, using a histone H2b:eGFP reporter. It has previously been known that mouse chimeras produced by the combination of diploid (2n) embryos with embryonic stem (ES) cells result in mixtures of the two components in epiblast-derived tissues. In contrast, the use of 4n host embryos with ES cells restricts 4n cells from the embryonic regions of chimeras, resulting in mice that are believed to be completely ES-derived. Using H2b:eGFP transgenic mice and ES cells, the behavior of 4n cells was determined at single cell resolution in 4n:2n injection and aggregation chimeras. We found a significant contribution of 4n cells to the embryonic ectoderm at gastrulation in every chimera analyzed. We show that the transition of the embryonic regions from a chimeric tissue to a predominantly 2n tissue occurs after gastrulation and that tetraploid cells may persist to midgestation. These findings suggest that the results of previously published tetraploid complementation assays may be influenced by the presence of tetraploid cells in the otherwise diploid embryonic regions.

  16. Nuclear and mitochondrial DNA in blastocoele fluid and embryo culture medium: evidence and potential clinical use.

    Science.gov (United States)

    Hammond, Elizabeth R; Shelling, Andrew N; Cree, Lynsey M

    2016-08-01

    The ability to screen embryos for aneuploidy or inherited disorders in a minimally invasive manner may represent a major advancement for the future of embryo viability assessment. Recent studies have demonstrated that both blastocoele fluid and embryo culture medium contain genetic material, which can be isolated and subjected to downstream genetic analysis. The blastocoele fluid may represent an alternative source of nuclear DNA for aneuploidy testing, although the degree to which the isolated genetic material is solely representative of the developing embryo is currently unclear. In addition to nuclear DNA, mitochondrial DNA (mtDNA) can be detected in the embryo culture medium. Currently, the origin of this nuclear and mtDNA has not been fully evaluated and there are several potential sources of contamination that may contribute to the genetic material detected in the culture medium. There is however evidence that the mtDNA content of the culture medium is related to embryo fragmentation levels and its presence is predictive of blastulation, indicating that embryo development may influence the levels of genetic material detected. If the levels of genetic material are strongly related to aspects of embryo quality, then this may be a novel biomarker of embryo viability. If the genetic material does have an embryo origin, the mechanisms by which DNA may be released into the blastocoele fluid and embryo culture medium are unknown, although apoptosis may play a role. While the presence of this genetic material is an exciting discovery, the DNA in the blastocoele fluid and embryo culture medium appears to be of low yield and integrity, which makes it challenging to study. Further research aimed at assessing the methodologies used for both isolating and analysing this genetic material, as well as tracing its origin, are needed in order to evaluate its potential for clinical use. Should such methodologies prove to be routinely successful and the DNA recovered

  17. Splitting of IVP bovine blastocyst affects morphology and gene expression of resulting demi-embryos during in vitro culture and in vivo elongation.

    Science.gov (United States)

    Velasquez, Alejandra E; Castro, Fidel O; Veraguas, Daniel; Cox, Jose F; Lara, Evelyn; Briones, Mario; Rodriguez-Alvarez, Lleretny

    2016-02-01

    Embryo splitting might be used to increase offspring yield and for molecular analysis of embryo competence. How splitting affects developmental potential of embryos is unknown. This research aimed to study the effect of bovine blastocyst splitting on morphological and gene expression homogeneity of demi-embryos and on embryo competence during elongation. Grade I bovine blastocyst produced in vitro were split into halves and distributed in nine groups (3 × 3 setting according to age and stage before splitting; age: days 7-9; stage: early, expanded and hatched blastocysts). Homogeneity and survival rate in vitro after splitting (12 h, days 10 and 13) and the effect of splitting on embryo development at elongation after embryo transfer (day 17) were assessed morphologically and by RT-qPCR. The genes analysed were OCT4, SOX2, NANOG, CDX2, TP1, TKDP1, EOMES, and BAX. Approximately 90% of split embryos had a well conserved defined inner cell mass (ICM), 70% of the halves had similar size with no differences in gene expression 12 h after splitting. Split embryos cultured further conserved normal and comparable morphology at day 10 of development; this situation changes at day 13 when embryo morphology and gene expression differed markedly among demi-embryos. Split and non-split blastocysts were transferred to recipient cows and were recovered at day 17. Fifty per cent of non-split embryos were larger than 100 mm (33% for split embryos). OCT4, SOX2, TP1 and EOMES levels were down-regulated in elongated embryos derived from split blastocysts. In conclusion, splitting day-8 blastocysts yields homogenous demi-embryos in terms of developmental capability and gene expression, but the initiation of the filamentous stage seems to be affected by the splitting.

  18. [Progress in proteomics of mammalian oocyte and early embryo].

    Science.gov (United States)

    Chen, Lingsheng; Xu, Ping; Shi, Deshun; Li, Xiangping

    2014-07-01

    The development of female germ cell is the cornerstone for animal reproduction. Mammalian oocyte and early embryo have many distinct phenomena and mechanisms during their growth and development, involving series dynamic changes of protein synthesis/degradation and phosphorylation. Research on the regulatory mechanism of oocyte division, maturation, and developmental principle of pre-implantation embryo is an important topic in the field of animal developmental biology. Proteomics using all of proteins expressed by a cell or tissue as research object, systematically identify, quantify and study the function of all these proteins. With the rapid development of protein separation and identification technology, proteomics provide some new methods and the research contents on fields of oogenesis, differentiation, maturation and quality control, such as protein quantification, modification, location and interaction important information which other omics technology can not provide. These information will contribute to uncover the molecular mechanisms of mammalian oocyte maturation and embryonic development. And it is great significant for improving the culture system of oocyte in vitro maturation, the efficiency of embryo production in vitro, somatic cell clone and transgenic animal production.

  19. Generating chimeric zebrafish embryos by transplantation.

    Science.gov (United States)

    Kemp, Hilary A; Carmany-Rampey, Amanda; Moens, Cecilia

    2009-07-17

    One of the most powerful tools used to gain insight into complex developmental processes is the analysis of chimeric embryos. A chimera is defined as an organism that contains cells from more than one animal; mosaics are one type of chimera in which cells from more than one genotype are mixed, usually wild-type and mutant. In the zebrafish, chimeras can be readily made by transplantation of cells from a donor embryo into a host embryo at the appropriate embryonic stage. Labeled donor cells are generated by injection of a lineage marker, such as a fluorescent dye, into the one-cell stage embryo. Labeled donor cells are removed from donor embryos and introduced into unlabeled host embryos using an oil-controlled glass pipette mounted on either a compound or dissecting microscope. Donor cells can in some cases be targeted to a specific region or tissue of the developing blastula or gastrula stage host embryo by choosing a transplantation site in the host embryo based on well-established fate maps.

  20. Efficient embryo transfer in the common marmoset monkey (Callithrix jacchus) with a reduced transfer volume: a non-surgical approach with cryopreserved late-stage embryos.

    Science.gov (United States)

    Ishibashi, Hidetoshi; Motohashi, Hideyuki H; Kumon, Mami; Yamamoto, Kazuhiro; Okada, Hironori; Okada, Takashi; Seki, Kazuhiko

    2013-05-01

    Among primates, the common marmoset is suitable for primate embryology research. Its small body size, however, has delayed the technical development of efficient embryo transfer. Furthermore, three factors have been determined to adversely affect the performance of marmoset embryo transfer: nonsurgical approaches, the use of cryopreserved embryos, and the use of late-stage embryos. Here we performed embryo transfer under conditions that included the above three factors and using either a small (1 μl or less) or a large volume (2-3 μl) of medium. The pregnancy and birth rates were 50% (5/10) and 27% (3/11), respectively, when using the large volume, and 80% (8/10) and 75% (9/12), respectively, when using the small volume. The latter scores exceed those of previous reports using comparable conditions. Thus, it appears that these three previously considered factors could be overcome, and we propose that reducing the transfer volume to 1 μl or less is essential for successful marmoset embryo transfer.

  1. Supplement of autologous ooplasm into porcine somatic cell nuclear transfer embryos does not alter embryo development.

    Science.gov (United States)

    Lee, W-J; Lee, J-H; Jeon, R-H; Jang, S-J; Lee, S-C; Park, J-S; Lee, S-L; King, W-A; Rho, G-J

    2017-02-13

    Somatic cell nuclear transfer (SCNT) is considered as the technique in which a somatic cell is introduced into an enucleated oocyte to make a cloned animal. However, it is unavoidable to lose a small amount of the ooplasm during enucleation step during SCNT procedure. The present study was aimed to uncover whether the supplement of autologous ooplasm could ameliorate the oocyte competence so as to improve low efficiency of embryo development in porcine SCNT. Autologous ooplasm-transferred (AOT) embryos were generated by the supplementation with autologous ooplasm into SCNT embryos. They were comparatively evaluated with respect to embryo developmental potential, the number of apoptotic body formation and gene expression including embryonic lineage differentiation, apoptosis, epigenetics and mitochondrial activity in comparison with parthenogenetic, in vitro-fertilized (IVF) and SCNT embryos. Although AOT embryos showed perfect fusion of autologous donor ooplasm with recipient SCNT embryos, the supplement of autologous ooplasm could not ameliorate embryo developmental potential in regard to the rate of blastocyst formation, total cell number and the number of apoptotic body. Furthermore, overall gene expression of AOT embryos was presented with no significant alterations in comparison with that of SCNT embryos. Taken together, the results of AOT demonstrated inability to make relevant values improved from the level of SCNT embryos to their IVF counterparts.

  2. Research of IGPC Control Strategy Based-on Hybrid Optimization for Power Station Boiler Superheated Steam Temperature

    Directory of Open Access Journals (Sweden)

    Benxian Xiao

    2014-01-01

    Full Text Available Implicit Generalized Predictive Control (IGPC algorithm can directly identify controller parameters without the need of solving Diophantine equation, thus can reduce the on-line algorithm computation time. In order to improve IGPC performance and extend its application, modified Particle Swarm Optimization (PSO algorithm is introduced into IGPC rolling horizon optimization, combined with general IGPC gradient optimization method under unconstrained condition, a new hybrid optimization method is obtained, this modified IGPC can be used to both of the non-constraint industry process control and the constraint industry process control. Aiming at the superheated steam temperature control of sub-critical 600MW boiler, a new cascade compound control strategy that combines an outer loop IGPC master adjuster and an inner loop PID auxiliary adjuster is adopted. Finally the simulation results have shown that the proposed method can constrain the control action, prevent dramatic change of the input signal, thus can achieve good static and dynamic performances.

  3. Research on Gear Shifting Process without Disengaging Clutch for a Parallel Hybrid Electric Vehicle Equipped with AMT

    Directory of Open Access Journals (Sweden)

    Hui-Long Yu

    2014-01-01

    Full Text Available Dynamic models of a single-shaft parallel hybrid electric vehicle (HEV equipped with automated mechanical transmission (AMT were described in different working stages during a gear shifting process without disengaging clutch. Parameters affecting the gear shifting time, components life, and gear shifting jerk in different transient states during a gear shifting process were deeply analyzed. The mathematical models considering the detailed synchronizer working process which can explain the gear shifting failure, long time gear shifting, and frequent synchronizer failure phenomenon in HEV were derived. Dynamic coordinated control strategy of the engine, motor, and actuators in different transient states considering the detailed working stages of synchronizer in a gear shifting process of a HEV is for the first time innovatively proposed according to the state of art references. Bench test and real road test results show that the proposed control strategy can improve the gear shifting quality in all its evaluation indexes significantly.

  4. The Use of Whole-Mount "in Situ" Hybridization to Illustrate Gene Expression Regulation

    Science.gov (United States)

    Llamusí, Beatriz; Muñoz-Soriano, Verónica; Paricio, Nuria; Artero, Rubén

    2014-01-01

    "In situ" hybridization is a widely used technique for studying gene expression. Here, we describe two experiments addressed to postgraduate genetics students in which the effect of transcription factors on gene expression is analyzed in "Drosophila embryos of different genotypes by whole-mount in situ hybridization. In one of the…

  5. Migration and Growth of Protoplanetary Embryos I: Convergence of Embryos in Protoplanetary Disks

    CERN Document Server

    Zhang, Xiaojia; Lin, Douglas N C; Li, Hui

    2014-01-01

    According to the core-accretion scenario, planets form in protostellar disks through the condensation of dust, coagulation of planetesimals, and emergence of protoplanetary embryos. At a few AU in a minimum mass nebula, embryos' growth is quenched by dynamical isolation due to the depletion of planetesimals in their feeding zone. However, embryos with masses ($M_p$) in the range of a few Earth masses ($M_\\oplus$) migrate toward a transition radius between the inner viscously heated and outer irradiated regions of their natal disk. Their limiting isolation mass increases with the planetesimals surface density. When $M_p > 10 M_\\oplus$, embryos efficiently accrete gas and evolve into cores of gas giants. We use numerical simulation to show that, despite streamline interference, convergent embryos essentially retain the strength of non-interacting embryos' Lindblad and corotation torque by their natal disks. In disks with modest surface density (or equivalently accretion rates), embryos capture each other in the...

  6. Embryo culture and rapid propagation of Syringa

    Institute of Scientific and Technical Information of China (English)

    ZHOU Li; DAI Li-min; SU Bao-ling

    2003-01-01

    Embryo of lilacs (Syringa L) culture in vitro and the rapid propagation were studied. The orthogonal experiments, including the selection of basal medium, embryo age and other factors such as sugar, benzyladenine (BA), naphthalene acetic acid (NAA) and glutamine (Gln), were carried out. The results indicated that the optimal medium for embryo culture was Monnier medium supplemented with NAA (0.001 mg@L-1), BA (0.1 mg@L-1), sugar (50 g@L-1), and Gln (400 mg@L-1), with a germination rate of 91.7% at least; the optimal embryo age was 50 d; and Gln had significant effects on the germination rate of embryo. Moreover, the optimal medium for subculture was MS+BA (2 mg@L-1)+NAA (0.001 mg@L-1)+Gln (0.5 mg@L-1), with the propagation coefficient of 3.6 at least.

  7. Nucleolar ultrastructure in bovine nuclear transfer embryos

    DEFF Research Database (Denmark)

    Kaňka, Jiří; Smith, Steven Dale; Soloy, Eva

    1999-01-01

    (nonactivated) or S phase (activated) cytoplasts. Control embryos were fixed at the two-, four-, early eight- and late eight-cell stages; nuclear transfer embryos were fixed at 1 and 3 hr post fusion and at the two-, four-, and eight-cell stages. Control embryos possessed a nucleolar precursor body throughout...... at 1 hr after fusion and, by 3 hr after fusion, it was restored again. At this time, the reticulated fibrillo-granular nucleolus had an almost round shape. The nucleolar precursor body seen in the two-cell stage nuclear transfer embryos consisted of intermingled filamentous components and secondary...... time intervals after fusion. In the two-cell stage nuclear transfer embryo, the originally reticulated nucleolus of the donor blastomere had changed into a typical nucleolar precursor body consisting of a homogeneous fibrillar structure. A primary vacuole appeared in the four-cell stage nuclear...

  8. Nucleolar ultrastructure in bovine nuclear transfer embryos

    DEFF Research Database (Denmark)

    Kaňka, Jiří; Smith, Steven Dale; Soloy, Eva

    1999-01-01

    (nonactivated) or S phase (activated) cytoplasts. Control embryos were fixed at the two-, four-, early eight- and late eight-cell stages; nuclear transfer embryos were fixed at 1 and 3 hr post fusion and at the two-, four-, and eight-cell stages. Control embryos possessed a nucleolar precursor body throughout...... at 1 hr after fusion and, by 3 hr after fusion, it was restored again. At this time, the reticulated fibrillo-granular nucleolus had an almost round shape. The nucleolar precursor body seen in the two-cell stage nuclear transfer embryos consisted of intermingled filamentous components and secondary...... time intervals after fusion. In the two-cell stage nuclear transfer embryo, the originally reticulated nucleolus of the donor blastomere had changed into a typical nucleolar precursor body consisting of a homogeneous fibrillar structure. A primary vacuole appeared in the four-cell stage nuclear...

  9. Microfluidics for mammalian embryo culture and selection: where do we stand now?

    Science.gov (United States)

    Le Gac, Séverine; Nordhoff, Verena

    2016-09-27

    The optimization of in-vitro culture conditions and the selection of the embryo(s) with the highest developmental competence are essential components in an ART program. Culture conditions are manifold and they underlie not always evidence-based research but also trends entering the IVF laboratory. At the moment, the idea of using sequential media according to the embryo requirements has been given up in favor of the use of single step media in an uninterrupted manner due to practical issues such as time-lapse incubators. The selection of the best embryo is performed using morphological and, recently, also morphokinetic criteria. In this review, we aim to demonstrate how the ART field may benefit from the use of microfluidic technology, with a particular focus on specific steps, namely the embryo in-vitro culture, embryo scoring and selection, and embryo cryopreservation. We first provide an overview of microfluidic and microfabricated devices, which have been developed for embryo culture, characterization of pre-implantation embryos (or in some instances a combination of both steps) and embryo cryopreservation. Building upon these existing platforms and the various capabilities offered by microfluidics, we discuss how this technology could provide integrated and automated systems, not only for real-time and multi-parametric monitoring of embryo development, but also for performing the entire ART procedure. Although microfluidic technology has been around for a couple of decades already, it has still not made its way into the clinics and IVF laboratories, which we discuss in terms of: (i) a lack of user-friendliness and automation of the microfluidic platforms, (ii) a lack of robust and convincing validation using human embryos and (iii) some psychological threshold for embryologists and practitioners to test and use microfluidic technology. In spite of these limitations, we envision that microfluidics is likely to have a significant impact in the field of ART, for

  10. Plug and Play Solar Power: Simplifying the Integration of Solar Energy in Hybrid Applications; Cooperative Research and Development Final Report, CRADA Number CRD-13-523

    Energy Technology Data Exchange (ETDEWEB)

    Lundstrom, Blake R. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-07-05

    The Commonwealth Scientific and Industrial Research Organisation (CSIRO) is Australia's national science agency. CSIRO received funding from the Australian Solar Institute (ASI) for the United States-Australia Solar Energy Collaboration (USASEC) project 1-USO032 Plug and Play Solar Power: Simplifying the Integration of Solar Energy in Hybrid Applications (Broader Project). The Australian Solar Institute (ASI) operated from August 2009 to December 2012 before being merged into the Australian Renewable Energy Agency (ARENA). The Broader Project sought to simplify the integration, accelerate the deployment, and lower the cost of solar energy in hybrid distributed generation applications by creating plug and play solar technology. CSIRO worked with the National Renewable Energy Laboratory (NREL) as set out in a Joint Work Statement to review communications protocols relevant to plug-and-play technology and perform prototype testing in its Energy System Integration Facility (ESIF). For the avoidance of doubt, this CRADA did not cover the whole of the Broader Project and only related to the work described in the Joint Work Statement, which was carried out by NREL.

  11. Undernutrition affects embryo quality of superovulated ewes.

    Science.gov (United States)

    Abecia, J A; Forcada, F; Palacín, I; Sánchez-Prieto, L; Sosa, C; Fernández-Foren, A; Meikle, A

    2015-02-01

    To determine the effect of undernutrition on embryo production and quality in superovulated sheep, 45 ewes were allocated into two groups to be fed diets that provided 1.5 (control, C; n = 20) or 0.5 (low nutrition, L; n = 25) times daily requirements for maintenance, from oestrous synchronization with intravaginal sponges to embryo collection. Embryos were collected 7 days after the onset of oestrus (day 0). Low nutrition resulted in lower live weight and body condition at embryo collection (P < 0.05). Diet (P < 0.01) and day of sampling (P < 0.001) significantly affected plasma non-esterified fatty acid (NEFA) and insulin concentrations. Plasma leptin concentrations decreased on day 7 only in L ewes. A significant effect of dietary treatment (P < 0.05) and day (P < 0.0001) was observed on plasma insulin-like growth factor (IGF)-I concentrations. The number of recovered oocytes and embryos did not differ between the groups (L: 15.4 ± 0.4; C: 12.4 ± 0.4). Recovery rate was lower (P < 0.05) in the L (60%) than in the C group (73%). The total number of embryos and number of viable-transferable embryos (5.0 ± 0.3 and 3.4 ± 0.3 embryos, respectively) of the L group were lower (P < 0.1) when compared with controls (8.4 ± 0.4 and 6.2 ± 0.4 embryos, respectively). Undernutrition during the period of superovulation and early embryonic development reduced total and viable number of embryos. These effects might be mediated by disruption of endocrine homeostasis, oviduct environment and/or oocyte quality.

  12. Research report for fiscal 1998. Research concerning studies for development of thermochemical solar hybrid fuel production system; 1998 nendo chosa hokokusho. Netsukagakuteki solar hybrid nenryo seisan system no kaihatsu kenkyu ni kakawaru chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    A solar heat-aided system is investigated, in which CO2 is recycled, with methanol, dimethyl ether, etc., serving as carriers of the solar heat energy. In the evaluation of validity of the system as a whole, the system scale and economy and technologies necessary for the system were studied, which was to find out whether solar methanol production was commercially feasible in the sun belt. It was concluded that solar methanol was capable of competing against LNG (liquefied natural gas) in cost, that Japan was able to establish its own technologies for developing coal gasification solar reactors using overseas technologies for information, and that therefore such a system was technologically and economically valid. In the study of related technologies as is, surveys were conducted on coal gasification, natural gas reforming furnaces, methanol synthesis, dimethyl ether synthesis, light condensing technology, current state and cost of solar reactors, etc. Also investigated were the marketability of solar hybrid fuel, CO2 reduction efficiency, and the construction cost at the assumed site of construction (Australia). (NEDO)

  13. Ants exhibit asymmetric hybridization in a mosaic hybrid zone.

    Science.gov (United States)

    Purcell, Jessica; Zahnd, Sacha; Athanasiades, Anouk; Türler, Rebecca; Chapuisat, Michel; Brelsford, Alan

    2016-10-01

    Research on hybridization between species provides unparalleled insights into the pre- and postzygotic isolating mechanisms that drive speciation. In social organisms, colony-level incompatibilities may provide additional reproductive barriers not present in solitary species, and hybrid zones offer an opportunity to identify these barriers. Here, we use genotyping-by-sequencing to sequence hundreds of markers in a hybrid zone between two socially polymorphic ant species, Formica selysi and Formica cinerea. We characterize the zone, determine the frequency of hybrid workers, infer whether hybrid queens or males are produced and investigate whether hybridization is influenced by colony social organization. We also compare cuticular hydrocarbon profiles and aggression levels between the two species. The hybrid zone exhibits a mosaic structure. The asymmetric distribution of hybrids skewed towards F. cinerea suggests a pattern of unidirectional nuclear gene flow from F. selysi into F. cinerea. The occurrence of backcrossed individuals indicates that hybrid queens and/or males are fertile, and the presence of the F. cinerea mitochondrial haplotype in 97% of hybrids shows that successful F1 hybrids will generally have F. cinerea mothers and F. selysi fathers. We found no evidence that social organization contributes to speciation, because hybrids occur in both single-queen and multiple-queen colonies. Strongly differentiated cuticular hydrocarbon profiles and heightened interspecific aggression further reveal that species recognition cues are both present and perceived. The discovery of fertile hybrids and asymmetrical gene flow is unusual in ants, and this hybrid zone will therefore provide an ideal system with which to investigate speciation in social insects.

  14. 杂交玉米研究中的自交系选育技术%Methods and Ways of Developing Inbred Lines in Hybrid Maize Research

    Institute of Scientific and Technical Information of China (English)

    杨峻芸; 谭静

    2001-01-01

    杂交玉米研究中,自交系选育是一个十分重要的环节。完成自交系选育,可以有多种不同的方法和途径,本文介绍了几种重要的选育方法,可供玉米育种工作者参考。%Development of inbred lines is very important in hybrid maize research.There are a lot of methods and ways to develop inbred lines.In this article,the authors introduced some methods and ways which are useful to breeders in their studies.

  15. TD-LTE和LTE FDD混合组网的互操作研究%Research on Interoperability of TD-LTE/LTE FDD Hybrid Networking

    Institute of Scientific and Technical Information of China (English)

    李佳俊; 宋甲英

    2015-01-01

    The optimum selection strategy of TD-LTE in TD-LTE/LTE FDD hybrid networking was researched in this paper. On the premise of user experience guaranteed, the strategy fully utilizes 2G/3G/4G network resources. In addition, the strategic recommendations on corresponding parameter conifguration of interoperability for TD-LTE, LTE FDD and WCDMA base stations were presented.%主要研究了TD-LTE和LTE FDD混合组网下的优选TD-LTE策略,在保障用户体验的同时充分利用2G/3G/4G网络资源,并给出了TD-LTE、LTE FDD以及WCDMA基站互操作相关参数配置策略建议。

  16. [Scientific ethics and frozen embryos].

    Science.gov (United States)

    Valenzuela, C Y

    2001-05-01

    Scientific Ethics is the theory and praxis of decisions. Philosophical Ethics is presented as the theory and praxis of the good. As the good differs among cultures, Philosophical Ethics is dependent on the endo-cultural good conception. The decision (included that one of adhesion or not to a world vision) depends on neuro-psychic specific factors: i) cognitive factors that include mostly the knowledge of the alternatives and their consequences and the ideological or religious conception of good in relation to the alternatives; ii) affective factors that make alternatives pleasant, unpleasant or neutral, attractive, repulsive or neutral; iii) emotional factors that associate to alternatives anger, peace or neutrality, sadness, happiness or neutrality; iv) value factors that assign importance, triviality or neutrality to alternatives, or assign them significance, irrelevancy or neutrality. There are unspecific factors such as the psychic energy, desire or others. Mixed factors such as attitude, motivation, intention and others. Scientific Ethics deals with the mind as a materio-energetic process which is different from the soul, eggs and embryos of any species are full individuals of that species, because, they have initiated a copy of their genome that specify, give autonomy and define them as individuals. For Scientific Ethics to leave frozen embryos like that for ever, to defrost and get rid of them or to use their cells for science are synonymous of killing them. To defrost them to use their cells as stem cells for somatic cell therapy or to implant them into uteri to continue their development is to maintain alive their cells, but only the implantation allows their maintenance as individuals, thus, being the only compatible with the Christian ethics. The compatibility of these alternatives with other ethics is discussed.

  17. Deciphering the mechanisms of developmental disorders: phenotype analysis of embryos from mutant mouse lines.

    Science.gov (United States)

    Wilson, Robert; McGuire, Christina; Mohun, Timothy

    2016-01-01

    The Deciphering the Mechanisms of Developmental Disorders (DMDD) consortium is a research programme set up to identify genes in the mouse, which if mutated (or knocked-out) result in embryonic lethality when homozygous, and initiate the study of why disruption of their function has such profound effects on embryo development and survival. The project uses a combination of comprehensive high resolution 3D imaging and tissue histology to identify abnormalities in embryo and placental structures of embryonic lethal lines. The image data we have collected and the phenotypes scored are freely available through the project website (http://dmdd.org.uk). In this article we describe the web interface to the images that allows the embryo data to be viewed at full resolution in different planes, discuss how to search the database for a phenotype, and our approach to organising the data for an embryo and a mutant line so it is easy to comprehend and intuitive to navigate.

  18. Myomaker mediates fusion of fast myocytes in zebrafish embryos

    Energy Technology Data Exchange (ETDEWEB)

    Landemaine, Aurélie; Rescan, Pierre-Yves; Gabillard, Jean-Charles, E-mail: Jean-charles.gabillard@rennes.inra.fr

    2014-09-05

    Highlights: • Myomaker is transiently expressed in fast myocytes during embryonic myogenesis. • Myomaker is essential for fast myocyte fusion in zebrafish. • The function of myomaker is conserved among Teleostomi. - Abstract: Myomaker (also called Tmem8c), a new membrane activator of myocyte fusion was recently discovered in mice. Using whole mount in situ hybridization on zebrafish embryos at different stages of embryonic development, we show that myomaker is transiently expressed in fast myocytes forming the bulk of zebrafish myotome. Zebrafish embryos injected with morpholino targeted against myomaker were alive after yolk resorption and appeared morphologically normal, but they were unable to swim, even under effect of a tactile stimulation. Confocal observations showed a marked phenotype characterized by the persistence of mononucleated muscle cells in the fast myotome at developmental stages where these cells normally fuse to form multinucleated myotubes. This indicates that myomaker is essential for myocyte fusion in zebrafish. Thus, there is an evolutionary conservation of myomaker expression and function among Teleostomi.

  19. ETHICS, EMBRYOS, AND EVIDENCE: A LOOK BACK AT WARNOCK.

    Science.gov (United States)

    Hammond-Browning, Natasha

    2015-01-01

    The Report of the Committee of Inquiry into Human Fertilisation and Embryology, the Warnock Report, forms the basis of the UK legislation on embryo research, and its influence continues to be felt, even though over 30 years have passed since its publication. The Warnock Committee was the first of its kind to consider how advancements in human fertilisation and embryology should be regulated. This article examines the evidence submitted to the Warnock Committee, upon which its members ultimately reached their conclusions. With ongoing debate as to the status of the human embryo, it is important to recognise that the legislative position is one that was reached after extensive consultation and consideration of submitted evidence by the Warnock Committee. This article considers the differing ethical viewpoints that were expressed by organisations both prior and post-publication of the Warnock Report, and how the Committee used that evidence to reach their conclusions, and ultimately calls for a new Warnock-style committee.

  20. Recent microfluidic devices for studying gamete and embryo biomechanics.

    Science.gov (United States)

    Lai, David; Takayama, Shuichi; Smith, Gary D

    2015-06-25

    The technical challenges of biomechanic research such as single cell analysis at a high monetary cost, labor, and time for just a small number of measurements is a good match to the strengths of microfluidic devices. New scientific discoveries in the fertilization and embryo development process, of which biomechanics is a major subset of interest, is crucial to fuel the continual improvement of clinical practice in assisted reproduction. The following review will highlight some recent microfluidic devices tailored for gamete and embryo biomechanics where biomimicry arises as a major theme of microfluidic device design and function, and the application of fundamental biomechanic principles are used to improve outcomes of cryopreservation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Factors influencing the outcome of embryo freezing and thawing program

    Institute of Scientific and Technical Information of China (English)

    叶英辉; 金帆; 徐晨明; 邢兰凤

    2002-01-01

    Objective: To investigate the factors that might influence the succ ess of an embryo freezing and thawing program. Method: The relationship betwee n the pregnancy rate in 73 cycles of embryo freezing and thawing program and the following factors was analyzed: maternal age, E2 level at the time of HCG trigg er, embryo storage time, number of thawed embryos transferred, presence of spons oring embryos and intact embryos. And the survival rate of thawed embryos with d ifferent morphology, cell stage and storage time was evaluated. Result: Tra nsfer with three or more than three thawed embryos resulted in pregnancy rates o f 38.5% and 35.7%, respectively, compared with 5.3% for transfer of fewer th an t hree embryos. The presence of sponsoring embryos and intact embryos significantl y increases pregnancy rate in embryo freezing and thawing program. No other fact or examined had any effect on pregnancy outcome. The survival rate of good morph ology embryos was higher than poor ones, but was not influenced by cell stage an d storage time. Conclusion: Embryo morphology before freezing, number of thaw ed embryos transferred and the presence of intact embryos are important to the o utcome of embryo freezing and thawing program.

  2. Fluid-particle hybrid simulation on the transports of plasma, recycling neutrals, and carbon impurities in the Korea Superconducting Tokamak Advanced Research divertor region

    Science.gov (United States)

    Kim, Deok-Kyu; Hong, Sang Hee

    2005-06-01

    A two-dimensional simulation modeling that has been performed in a self-consistent way for analysis on the fully coupled transports of plasma, recycling neutrals, and intrinsic carbon impurities in the divertor domain of tokamaks is presented. The numerical model coupling the three major species transports in the tokamak edge is based on a fluid-particle hybrid approach where the plasma is described as a single magnetohydrodynamic fluid while the neutrals and impurities are treated as kinetic particles using the Monte Carlo technique. This simulation code is applied to the KSTAR (Korea Superconducting Tokamak Advanced Research) tokamak [G. S. Lee, J. Kim, S. M. Hwang et al., Nucl. Fusion 40, 575 (2000)] to calculate the peak heat flux on the divertor plate and to explore the divertor plasma behavior depending on the upstream conditions in its base line operation mode for various values of input heating power and separatrix plasma density. The numerical modeling for the KSTAR tokamak shows that its full-powered operation is subject to the peak heat loads on the divertor plate exceeding an engineering limit, and reveals that the recycling zone is formed in front of the divertor by increasing plasma density and by reducing power flow into the scrape-off layer. Compared with other researchers' work, the present hybrid simulation more rigorously reproduces severe electron pressure losses along field lines by the presence of recycling zone accounting for the transitions between the sheath limited and the detached divertor regimes. The substantial profile changes in carbon impurity population and ionic composition also represent the key features of this divertor regime transition.

  3. Comparison of clinical outcomes between fresh embryo transfers and frozen-thawed embryo transfers.

    Science.gov (United States)

    Shen, Chunjuan; Shu, Defeng; Zhao, Xiaojie; Gao, Ying

    2014-06-01

    Advances in embryo culture technology and cryopreservation have led to a shift in in vitro fertilization (IVF) from early fresh or frozen-thawed cleavage embryo transfer to fresh or frozen-thawed blastocyst stage transfer. To compare the clinical outcomes of fresh embryo transfers and frozen-thawed embryo transfers. In this retrospective case control study, patients undergoing IVF cycles from January 2012 to December 2012 were enrolled in Assisted Reproduction of Wuhan Union Hospital were enrolled. A total of 1891 cycle contains 1150 fresh embryo transfers and 741 frozen-thawed embryo transfers were studied. All data were transferred directly to SPSS 18 and analyzed. Clinical pregnancy rates of fresh cleavage-stage embryo transfers compared with fresh blastocyst transfers, frozen-thawed cleavage-stage embryo transfers, post thaw cleavage-stage extended blastocyst culture transfers and frozen-thawed blastocyst transfers were 52.7%, 35.88%, 35.29%, 47.75%, 59.8% in patients under 35 years of ages and 41.24%, 26.92%, 11.32%, 46.15%, 55.8% in patients older than 35 years old, respectively. The multiple pregnancy rates, abortion rates and ectopic pregnancy rates did not differ significantly among the five groups. The clinical pregnancy rates were not different significantly between fresh cleavage-stage embryo transfers and fresh blastocyst transfers. But the clinical pregnancy rate of frozen-thawed blastocyst transfer was the highest among fresh/frozen-thawed embryo transfers.

  4. Research on Theories and Techniques of Irrigation for Safeguarding Seed Production of Two-Line Hybrid Rice

    Institute of Scientific and Technical Information of China (English)

    ZOU Jiang-shi; L(U) Chuan-gen; YAO Ke-min; HU Ning; XIA Shi-jian

    2006-01-01

    By inducing frequency, intensity and duration of lower temperature in the middle and last ten-day periods in August in the rice-growing areas of southern China, increasing temperature for safe seed production was defined as 2℃. During the sensitive period of fertility, characters of panicle height and canopy structure of TGMS rice, Pei'ai64S, were measured.Results showed that temperature changes caused by irrigation in fields were below 40 cm of rice plant, and heating effect was significant at 20 cm when the temperature was increased by 3.1℃. For the present study, the following irrigation techniques were put forth: the water depth of 15-20 cm, current water used, irrigating after 17:00 and bailing at 10:00 in sunny or cloudy weather, irrigating on whole day, in shady or rainy weather, increasing inflows and outflows in large fields. In the present experiment, pollen fertility and self-fertilized seed setting rate accepted that the techniques were feasible and effective for against lower temperature and safeguarding seed production of two-line hybrid rice.

  5. In-vivo centrifugation of Drosophila embryos.

    Science.gov (United States)

    Tran, Susan L; Welte, Michael A

    2010-06-23

    A major strategy for purifying and isolating different types of intracellular organelles is to separate them from each other based on differences in buoyant density. However, when cells are disrupted prior to centrifugation, proteins and organelles in this non-native environment often inappropriately stick to each other. Here we describe a method to separate organelles by density in intact, living Drosophila embryos. Early embryos before cellularization are harvested from population cages, and their outer egg shells are removed by treatment with 50% bleach. Embryos are then transferred to a small agar plate and inserted, posterior end first, into small vertical holes in the agar. The plates containing embedded embryos are centrifuged for 30 min at 3000 g. The agar supports the embryos and keeps them in a defined orientation. Afterwards, the embryos are dug out of the agar with a blunt needle. Centrifugation separates major organelles into distinct layers, a stratification easily visible by bright-field microscopy. A number of fluorescent markers are available to confirm successful stratification in living embryos. Proteins associated with certain organelles will be enriched in a particular layer, demonstrating colocalization. Individual layers can be recovered for biochemical analysis or transplantation into donor eggs. This technique is applicable for organelle separation in other large cells, including the eggs and oocytes of diverse species.

  6. Hybrid2 - The hybrid power system simulation model

    Energy Technology Data Exchange (ETDEWEB)

    Baring-Gould, E.I.; Green, H.J.; Dijk, V.A.P. van [National Renewable Energy Lab., Golden, CO (United States); Manwell, J.F. [Univ. of Massachusetts, Amherst, MA (United States)

    1996-12-31

    There is a large-scale need and desire for energy in remote communities, especially in the developing world; however the lack of a user friendly, flexible performance prediction model for hybrid power systems incorporating renewables hindered the analysis of hybrids as options to conventional solutions. A user friendly model was needed with the versatility to simulate the many system locations, widely varying hardware configurations, and differing control options for potential hybrid power systems. To meet these ends, researchers from the National Renewable Energy Laboratory (NREL) and the University of Massachusetts (UMass) developed the Hybrid2 software. This paper provides an overview of the capabilities, features, and functionality of the Hybrid2 code, discusses its validation and future plans. Model availability and technical support provided to Hybrid2 users are also discussed. 12 refs., 3 figs., 4 tabs.

  7. Mechanisms of cadmium-caused eye hypoplasia and hypopigmentation in zebrafish embryos

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ting, E-mail: zting@webmail.hzau.edu.cn; Zhou, Xin-Ying, E-mail: 290356082@qq.com; Ma, Xu-Fa, E-mail: xufama@mail.hzau.edu.cn; Liu, Jing-Xia, E-mail: ichliu@mail.hzau.edu.cn

    2015-10-15

    Highlights: Using high-throughput in situ hybridization screening, we found that genes labeling the neural crest and its derivative pigment cells were sensitive to cadmium toxicity during zebrafish organogenesis, which might contribute to the molecular mechanisms underlying the phenotype defects of head and eye hypoplasia and hypopigmentation in cadmium-exposed embryos. Based on neural crest markers, we identified the doses and times of cadmium exposure that cause damage to the zebrafish organogenesis, and we also found that compounds BIO or RA could neutralize the toxic effects of cadmium. - Abstract: Cadmium-caused head and eye hypoplasia and hypopigmentation has been recognized for a long time, but knowledge of the underlying mechanisms is limited. In this study, we found that high mortality occurred in exposed embryos after 24 hpf, when cadmium (Cd) dosage was above 17.8 μM. Using high-throughput in situ hybridization screening, we found that genes labelling the neural crest and its derivative pigment cells exhibited obviously reduced expression in Cd-exposed embryos from 24 hpf, 2 days earlier than head and eye hypoplasia and hypopigmentation occurred. Moreover, based on expression of crestin, a neural crest marker, we found that embryos before the gastrula stage were more sensitive to cadmium toxicity and that damage caused by Cd on embryogenesis was dosage dependent. In addition, by phenotype observation and detection of neural crest and pigment cell markers, we found that BIO and retinoic acid (RA) could neutralize the toxic effects of Cd on zebrafish embryogenesis. In this study, we first determined that Cd blocked the formation of the neural crest and inhibited specification of pigment cells, which might contribute to the molecular mechanisms underlying the phenotype defects of head and eye hypoplasia and hypopigmentation in Cd-exposed embryos. Moreover, we found that compounds BIO or RA could neutralize the toxic effects of Cd.

  8. Development and characterization of interspecific hybrids between Oryza sativa and O. latifolia by in situ hybridization

    Institute of Scientific and Technical Information of China (English)

    YI ChuanDeng; TANG ShuZhu; ZHOU Yong; LIANG GuoHua; GONG ZhiYun; GU MingHong

    2008-01-01

    Oryza sativa and O. latifolia belong to the AA and CCDD genomes of Oryza, respectively. In this study, interspecific hybrids of these species were obtained using the embryo rescue technique. Hybrid pani-cle traits, such as long awns, small grain, exoteric large purple stigma, grain shattering and dispersed panicles, resemble that of the paternal parent, O. latifolia, whereas there is obvious heterosis in such respects as plant height, tillering ability and vegetative vigor. Chromosome pairing and the genomic components of the hybrid were subsequently investigated using genomic in situ hybridization (GISH) and fluorescent in situ hybridization (FISH) analysis. Based on the mitotic metaphase chromosome numbers of the root tips investigated, the hybrid is a triploid with 36 chromosomes. The genomic con-stitution of the hybrid is ACD. In the meiotic metaphase I of the hybrid pollen mother cell, poor chro-mosome pairing was identified and most of the chromosomes were univalent, which resulted in com-plete male sterility in the hybrid.

  9. Comparative Embryological Studies on Infertility of Interspecific Hybridizations Between Oryza sativa with Different Ploidy Levels and O.officinalis

    Institute of Scientific and Technical Information of China (English)

    FU Xue-lin; LU Yong-gen; LIU Xiang-dong; LI Jin-quan; ZHAO Xing-juan

    2009-01-01

    As maternal parents, diploid (L202-2x) and autotetraploid (L202-4x) of Oryza sativa cv. L202 were crossed with O. officinalis. Embryo development and fertilization in these two crosses were comparatively studied. There were no mature hybrid seeds obtained because all the hybridized spikelets died 30 days after pollination. The main reasons for no seed set were abnormal fertilization and development of the embryos and endosperms in the interspecific hybrids. There were double- fertilization, egg cell single-fertilization and non-fertilization in these crosses. Although 59.45% and 54.87% of hybrid embryos produced in the crosses of L202-2x/O. officinalis and L202-4x/O. officinalis, respectively, hybrid embryos ceased to develop or degenerated and plenty of free endosperm nuclei were in disaggregating state without developing cellular endosperms three days after pollination. Besides, some embryological differences in these two crosses were found, that is, the rate of double-fertilization and total rate of double- and single-fertilization in L202-2x/O. officinalis were higher than those in L202-4x/O. officinalis. The embryo and endosperm of hybrids developed more slowly, and embryos and free endosperm nuclei were more severely degenerated in L202-4x/O. officinalis than in L202-2x/O. officinalis. Five days after pollination, a few of embryos in L202-2x/O. officinalis developed into pear-shaped ones, however, embryos in L202-4x/O. officinalis were all degenerated. Therefore, it is more difficult to obtain interspecific hybrids by wide crosses between autotetraploid of O. sativa and O. officinalis.

  10. Biofluid Flow Simulations of Embryo Transfer

    Science.gov (United States)

    Shi, W. P.; Ding, D. L.

    2011-09-01

    The investigation of the fluid flow for embryo transfer (ET) procedure may find the way to increase the success rate of the assisted reproductive technologies. In this paper, the transferred liquid flow in the uterine cavity during ET procedure is simulated by a two dimensional multiphase flow model, and the discrete phase model is adopted to trace the embryo motion. Through the investigation on the transferred liquid outline and the track of each embryo in ET cases with different parameters, we summarize the effect of transferred liquid viscosity and distance between catheter tip and uterine fundus. According to the numerical results, we recommend the optimizing standard to perform the ET procedure.

  11. Association between Number of Formed Embryos, Embryo Morphology and Clinical Pregnancy Rate after Intracytoplasmic Sperm Injection.

    Science.gov (United States)

    Luz, Caroline Mantovani da; Giorgi, Vanessa Silvestre Innocenti; Coelho Neto, Marcela Alencar; Martins, Wellington de Paula; Ferriani, Rui Alberto; Navarro, Paula Andrea

    2016-09-01

    Introduction Infertility has a high prevalence in the general population, affecting ∼ 5 to 15% of couples in reproductive age. The assisted reproduction techniques (ART) include in vitro manipulation of gametes and embryos and are an important treatment indicated to these couples. It is well accepted that the implantation rate is positively influenced by the morphology of transferred embryos. However, we question if, apart from the assessment of embryo morphology, the number of produced embryos per cycle is also related to pregnancy rates in the first fresh transfer cycle. Purpose To evaluate the clinical pregnancy rate according to the number of formed embryos and the transfer of top quality embryos (TQEs). Methods In a retrospective cohort study, between January 2011 and December 2012, we evaluated women who underwent intracytoplasmic sperm injection (ICSI), aged < 40 years, and with at least 1 formed embryo fresh transferred in cleavage stage. These women were stratified into 3 groups according to the number of formed embryos (1 embryo, 2-3 and ≥ 4 embryos). Each group was divided into 2 subgroups according to the presence or not of at least 1 transferred TQE (1 with TQE; 1 without TQE; 2-3 with TQE, 2-3 without TQE; ≥ 4 with TQE; ≥ 4 without TQE). The clinical pregnancy rates were compared in each subgroup based on the presence or absence of at least one transferred TQE. Results During the study period, 636 women had at least one embryo to be transferred in the first fresh cycle (17.8% had 1 formed embryo [32.7% with TQE versus 67.3% without TQE], 42.1% of women had 2-3 formed embryos [55.6% with TQE versus 44.4% without TQE], and 40.1% of patients had ≥ 4 formed embryos [73.7% with TQE versus 26.3% without TQE]). The clinical pregnancy rate was significantly higher in the subgroup with ≥ 4 formed embryos with at least 1 transfered TQE (45.2%) compared with the subgroup without TQE (28.4%). Conclusions Having at

  12. Research aimed at improving both mood and weight (RAINBOW) in primary care: A type 1 hybrid design randomized controlled trial.

    Science.gov (United States)

    Ma, Jun; Yank, Veronica; Lv, Nan; Goldhaber-Fiebert, Jeremy D; Lewis, Megan A; Kramer, M Kaye; Snowden, Mark B; Rosas, Lisa G; Xiao, Lan; Blonstein, Andrea C

    2015-07-01

    Effective interventions targeting comorbid obesity and depression are critical given the increasing prevalence and worsened outcomes for patients with both conditions. RAINBOW is a type 1 hybrid design randomized controlled trial. The objective is to evaluate the clinical and cost effectiveness and implementation potential of an integrated, technology-enhanced, collaborative care model for treating comorbid obesity and depression in primary care. Obese and depressed adults (n = 404) will be randomized to usual care enhanced with the provision of a pedometer and information about the health system's services for mood or weight management (control) or with the Integrated Coaching for Better Mood and Weight (I-CARE) program (intervention). The 12-month I-CARE program synergistically integrates two proven behavioral interventions: problem-solving therapy with as-needed intensification of pharmacotherapy for depression (PEARLS) and standardized behavioral treatment for obesity (Group Lifestyle Balance(™)). It utilizes traditional (e.g., office visits and phone consults) and emerging care delivery modalities (e.g., patient web portal and mobile applications). Follow-up assessments will occur at 6, 12, 18, and 24 months. We hypothesize that compared with controls, I-CARE participants will have greater improvements in weight and depression severity measured by the 20-item Depression Symptom Checklist at 12 months, which will be sustained at 24 months. We will also assess I-CARE's cost-effectiveness and use mixed methods to examine its potential for reach, adoption, implementation, and maintenance. This study offers the potential to change how obese and depressed adults are treated-through a new model of accessible and integrative lifestyle medicine and mental health expertise-in primary care.

  13. Combining stated and revealed choice research to simulate the neighbor effect: The case of hybrid-electric vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Axsen, Jonn [Institute of Transportation Studies, Univ. of California at Davis, 2028 Academic Surge, One Shields Avenue, Davis, CA 95616 (United States); Mountain, Dean C. [DeGroote School of Business, McMaster Univ., 1280 Main Street West, Hamilton, ON L8S 4M4 (Canada); Jaccard, Mark [School of Resource and Environmental Management, Simon Fraser Univ., 8888 Univ. Drive, Burnaby, BC V5A 1S6 (Canada)

    2009-08-15

    According to intuition and theories of diffusion, consumer preferences develop along with technological change. However, most economic models designed for policy simulation unrealistically assume static preferences. To improve the behavioral realism of an energy-economy policy model, this study investigates the ''neighbor effect'', where a new technology becomes more desirable as its adoption becomes more widespread in the market. We measure this effect as a change in aggregated willingness to pay under different levels of technology penetration. Focusing on hybrid-electric vehicles (HEVs), an online survey experiment collected stated preference (SP) data from 535 Canadian and 408 Californian vehicle owners under different hypothetical market conditions. Revealed preference (RP) data was collected from the same respondents by eliciting the year, make and model of recent vehicle purchases from regions with different degrees of HEV popularity: Canada with 0.17% new market share, and California with 3.0% new market share. We compare choice models estimated from RP data only with three joint SP-RP estimation techniques, each assigning a different weight to the influence of SP and RP data in coefficient estimates. Statistically, models allowing more RP influence outperform SP influenced models. However, results suggest that because the RP data in this study is afflicted by multicollinearity, techniques that allow more SP influence in the beta estimates while maintaining RP data for calibrating vehicle class constraints produce more realistic estimates of willingness to pay. Furthermore, SP influenced coefficient estimates also translate to more realistic behavioral parameters for CIMS, allowing more sensitivity to policy simulations. (author)

  14. Hybrid Metaheuristics

    CERN Document Server

    2013-01-01

    The main goal of this book is to provide a state of the art of hybrid metaheuristics. The book provides a complete background that enables readers to design and implement hybrid metaheuristics to solve complex optimization problems (continuous/discrete, mono-objective/multi-objective, optimization under uncertainty) in a diverse range of application domains. Readers learn to solve large scale problems quickly and efficiently combining metaheuristics with complementary metaheuristics, mathematical programming, constraint programming and machine learning. Numerous real-world examples of problems and solutions demonstrate how hybrid metaheuristics are applied in such fields as networks, logistics and transportation, bio-medical, engineering design, scheduling.

  15. Factors influencing the outcome of embryo freezing and Ihawing program

    Institute of Scientific and Technical Information of China (English)

    叶英辉; 金帆; 徐晨明; 邢兰凤

    2002-01-01

    Objective: To investigate the factors that might influence the sucess of an ernbryo freezing and thawing program.Method: The relationship between the pregnancy rate in 73 cycles of embryo freezing and thewing program and the following factors was analyzed;matermal age,E2 level at the time of HCG trigger,embryo storage time,number of thawed embryos transferred,presence of sponsoring embryos and intact embryos.And the suvival rate of thawed embryos with different morphology,cell stage and storage time was evaluated.Result:Transfer with three of more than three thawed embryos resulted in pragnancy rates of 38.5% and 35.7%,respectively.compared with 5.3% for transfer of fewer than three embryos.The presence of sponsoring embryos and intact embryos significantly incresses pregnancy rate in embryo freezing and thawing program .No other factor examined had any effect on pregnancy outcome.The survival rate of good morphology embryos was higher than poor ones,but was not influenced by cell stage and storage time.Conclusion:Embryo morphology before freezing , number of thawed embryos transferred and the presence of intact embryos are important to the outcome of embryo freezing and thawing program.

  16. Developmental competence of porcine chimeric embryos produced by aggregation

    DEFF Research Database (Denmark)

    Li, Juan; Jakobsen, Jannik E.; Xiong, Qiang

    2015-01-01

    The purpose of our study was to compare the developmental competence and blastomere allocation of porcine chimeric embryos formed by micro-well aggregation. Chimeras were created by aggregating either two blastomeres originating from 2-cell embryos or two whole embryos, where embryos were produced...

  17. Analysis of the meiosis in the F1 hybrids of Longiflorum x Asiatic(LA) of lilies (Lilium) using genomic in situ hybridization

    Institute of Scientific and Technical Information of China (English)

    Shujun Zhou; Munikote S. Ramanna; Richard G.F.Visser; Jaap M. van Tuyl

    2008-01-01

    Longiflorum and Asiatic lilies of the genus Lilium of the family Liliaeeae are two important groups of modern lily eultivars. One of the main trends of lily breeding is to realize introgression between these groups. With cut style pollination and embryo rescue, distant hybrids between the two groups have been obtained. However, the F1hybrids are highly sterile or some of them could produce a small number of 2n gametes, and their BC1 progenies are usually triploids. Dutch lily breeders have selected many cultivars from these BC1 progenies based on their variation. It is presumably suggested that such variation could be caused by intergenomic recombination and abnormal meiosis during gamete formation in F1 hybrids of Longiflorum x Asiatic (LA) hybrids in Lilium. Therefore, the meiotic process of ten F1 LA hybrids was cytologically investigated using genomic in situ hybridization and traditional cytological methods in the present research.The results showed that: at metaphase I, the homoeologous chromosome pairing among different F1hybrids ranged from 2.0 to 11.4 bi-valents formed by homoeologous chromosomes per pollen mother cell (PMC), and very few multivalents, and even very few bivalents were formed by two chromosomes within one genome rather than homoeologous chromosomes in some PMCs; at anaphase I, all biva-lents were disjoined and most univalents were divided. Both the disjoined bivalents (half-bivalents) and the divided univalents (sister chromatids) moved to the opposite poles, and then formed two groups of chromosomes; because the two resulting half-bivalents retained their axes in the cell undisturbed, many crossover types, including single crossovers, three strand double crossovers, four strand double crossovers, four strand triple crossovers, and four strand multiple crossovers between the non-sister chromatids in the tetrads of bivalents,were clearly inferred by analyzing the breakpoints on the disjoined bivalents. The present investigation not only

  18. Aberrant gene expression patterns in extraembryonic tissue from cloned porcine embryos.

    Science.gov (United States)

    Park, Mi-Ryung; Im, Gi-Sun; Kim, Sung Woo; Hwang, Seongsoo; Park, Jae-Hong; Kim, Hyun; Do, Yoon Jung; Park, Soo Bon; Yang, Bo-Suck; Song, Young Min; Cho, Jae-Hyeon; Ko, Yeoung-Gyu

    2013-06-01

    The abnormal development of embryos reconstructed by somatic cell nuclear transfer (SCNT) is considered to be associated with consequent changes in gene expression following errors in epigenetic reprogramming. In this study, we carried out SCNT using donor fibroblast cells derived from 3-way hybrids (Landrace×Duroc×Yorkshire). A total of 655 SCNT embryos were transferred, and 6.97±2.3 cloned fetuses were successfully recovered from three surrogates at gestational day 30. An analysis of the 6.97±2.3 cloned embryos revealed that most had severe extraembryonic defects. The extraembryonic tissue from the SCNT embryos was abnormally small compared with that of the control. To investigate the differentially expressed genes between the SCNT and control extraembryonic tissues, we compared the gene expression profiles of the extraembryonic tissues from gestational day 30 cloned pig embryos with those from the control using an annealing control primer-based GeneFishing polymerase chain reaction. As a result, we found that a total of 50 genes were differentially expressed by utilizing 120 ACPs, 38 genes of which were known. Among them, 26 genes were up-regulated, whereas 12 genes were down-regulated. Real-time RT-PCR showed that apoptosis-related genes were expressed significantly higher in SCNT extraembryonic tissue than in the control, whereas metabolism-related genes were expressed at significantly lower levels in the SCNT extraembryonic tissue. These observations strongly indicate that early gestational death of SCNT embryo is caused, at least in part, by the disruption of developing extraembryonic tissues as a result of aberrant gene expression, which results in abnormal apoptosis and metabolism.

  19. Identification and characterization of a novel gene differentially expressed in zebrafish cross-subfamily cloned embryos

    Directory of Open Access Journals (Sweden)

    Wang Ya-Ping

    2008-03-01

    Full Text Available Abstract Background Cross-species nuclear transfer has been shown to be a potent approach to retain the genetic viability of a certain species near extinction. However, most embryos produced by cross-species nuclear transfer were compromised because that they were unable to develop to later stages. Gene expression analysis of cross-species cloned embryos will yield new insights into the regulatory mechanisms involved in cross-species nuclear transfer and embryonic development. Results A novel gene, K31, was identified as an up-regulated gene in fish cross-subfamily cloned embryos using SSH approach and RACE method. K31 complete cDNA sequence is 1106 base pairs (bp in length, with a 342 bp open reading frame (ORF encoding a putative protein of 113 amino acids (aa. Comparative analysis revealed no homologous known gene in zebrafish and other species database. K31 protein contains a putative transmembrane helix and five putative phosphorylation sites but without a signal peptide. Expression pattern analysis by real time RT-PCR and whole-mount in situ hybridization (WISH shows that it has the characteristics of constitutively expressed gene. Sub-cellular localization assay shows that K31 protein can not penetrate the nuclei. Interestingly, over-expression of K31 gene can cause lethality in the epithelioma papulosum cyprinid (EPC cells in cell culture, which gave hint to the inefficient reprogramming events occurred in cloned embryos. Conclusion Taken together, our findings indicated that K31 gene is a novel gene differentially expressed in fish cross-subfamily cloned embryos and over-expression of K31 gene can cause lethality of cultured fish cells. To our knowledge, this is the first report on the determination of novel genes involved in nucleo-cytoplasmic interaction of fish cross-subfamily cloned embryos.

  20. Splitting and biopsy for bovine embryo sexing under field conditions.

    Science.gov (United States)

    Lopes, R F; Forell, F; Oliveira, A T; Rodrigues, J L

    2001-12-01

    Improvements on embryo micromanipulation techniques led to the use of embryo bisection technology in commercial embryo transfer programs, and made possible the direct genetic analysis of preimplantation bovine embryos by biopsy. For example, aspiration and microsection, allow bovine embryos sexing by detection of male-specific Y-chromosome in a sample of embryonic cells. We report on the application of the methodologies of splitting and biopsy of bovine embryos in field conditions, and on the results of embryo sex determination by the polymerase chain reaction (PCR). Pregnancy rates achieved with fresh bisected or biopsied embryos (50 to 60%) were similar to the fresh intact embryos (55 to 61%). The PCR protocol used for embryo sexing showed 92% to 94% of efficiency and 90 to 100% of accuracy. These results demonstrate these procedures are suitable for use in field conditions.

  1. Steroidal alkaloid toxicity to fish embryos.

    Science.gov (United States)

    Crawford, L; Kocan, R M

    1993-02-01

    Embryos of two species of fish were evaluated for their suitability as model systems for steroidal alkaloid toxicity, the Japanese rice fish, medaka (Oryzius latipes) and the rainbow trout (Oncorhynchus mykiss). Additionally, the equine neurotoxic sesquiterpene lactone repin, was also tested. A PROBIT program was used to evaluate the EC1, EC50 and EC99 as well as the associated confidence limits. The steroidal alkaloids tested were the Solanum potato glycoalkaloids alpha-chaconine, alpha-solanine, the aglyclones solanidine and solasodine and the Veratrum alkaloid, jervine. Embryo mortality, likely due to structural or functional abnormalities in the early development stages of the embryo, were the only response observed in both species. The rainbow trout exhibited a toxic response to chaconine, solasidine, repin and solanine but the medaka embryos were only affected by the compounds, chaconine and solanine. Rainbow trout may indeed serve as a good lower vertebrate model for studying the toxicity of steroidal alkaloids.

  2. Laser fusion of mouse embryonic cells and intra-embryonic fusion of blastomeres without affecting the embryo integrity.

    Directory of Open Access Journals (Sweden)

    Alexander Krivokharchenko

    Full Text Available Manipulation with early mammalian embryos is the one of the most important approach to study preimplantation development. Artificial cell fusion is a research tool for various biotechnological experiments. However, the existing methods have various disadvantages, first of them impossibility to fuse selected cells within multicellular structures like mammalian preimplantation embryos. In our experiments we have successfully used high repetition rate picosecond near infrared laser beam for fusion of pairs of oocytes and oocytes with blastomeres. Fused cells looked morphologically normal and keep their ability for further divisions in vitro. We also fused two or three blastomeres inside four-cell mouse embryos. The presence of one, two or three nuclei in different blastomeres of the same early preimplantation mouse embryo was confirmed under UV-light after staining of DNA with the vital dye Hoechst-33342. The most of established embryos demonstrated high viability and developed in vitro to the blastocyst stage. We demonstrated for the first time the use of laser beam for the fusion of various embryonic cells of different size and of two or three blastomeres inside of four-cell mouse embryos without affecting the embryo's integrity and viability. These embryos with blastomeres of various ploidy maybe unique model for numerous purposes. Thus, we propose laser optical manipulation as a new tool for investigation of fundamental mechanisms of mammalian development.

  3. Laser fusion of mouse embryonic cells and intra-embryonic fusion of blastomeres without affecting the embryo integrity.

    Science.gov (United States)

    Krivokharchenko, Alexander; Karmenyan, Artashes; Sarkisov, Oleg; Bader, Michael; Chiou, Arthur; Shakhbazyan, Avetik

    2012-01-01

    Manipulation with early mammalian embryos is the one of the most important approach to study preimplantation development. Artificial cell fusion is a research tool for various biotechnological experiments. However, the existing methods have various disadvantages, first of them impossibility to fuse selected cells within multicellular structures like mammalian preimplantation embryos. In our experiments we have successfully used high repetition rate picosecond near infrared laser beam for fusion of pairs of oocytes and oocytes with blastomeres. Fused cells looked morphologically normal and keep their ability for further divisions in vitro. We also fused two or three blastomeres inside four-cell mouse embryos. The presence of one, two or three nuclei in different blastomeres of the same early preimplantation mouse embryo was confirmed under UV-light after staining of DNA with the vital dye Hoechst-33342. The most of established embryos demonstrated high viability and developed in vitro to the blastocyst stage. We demonstrated for the first time the use of laser beam for the fusion of various embryonic cells of different size and of two or three blastomeres inside of four-cell mouse embryos without affecting the embryo's integrity and viability. These embryos with blastomeres of various ploidy maybe unique model for numerous purposes. Thus, we propose laser optical manipulation as a new tool for investigation of fundamental mechanisms of mammalian development.

  4. Hybrid solar cells of conjugated polymers metal-oxide nanocrystals blends; state of the art and future research challenges in Indonesia

    Science.gov (United States)

    Bahtiar, Ayi

    2013-09-01

    Ever-increasing world energy demand, depleting non-renewable energy resources and disruptive climate change due to greenhouse gases has aroused much interest in alternative renewable energy sources. Solar energy is one of the best available alternatives, for it is both abundant and clean. Solar cell is an effective device for converting solar energy into electricity. Indonesia is located on the equator where the sunlight is always available in abundance throughout the year; therefore solar cell would become the main source of electrical energy in Indonesia. However, the high cost of inorganic solar cells in spite of their high power conversion efficiency (PCE) has been a major constrain for their mass utilization in Indonesia. The only way to reduce the cost of production and installation is to find other materials which offer low-cost and easy processing into solar cells. Polymer solar cells have been intensively investigated for high performance and low-cost solar cells. Today, 9-11% power conversion efficiency (PCE) of small area polymer solar cells and 2-4% PCE of large area or module solar cells are already achieved. However, for practical application and mass production, 10% or higher PCE of module solar cells is highly required. The main strategic issue for improving the PCE is to use blend of conjugated polymer-metal oxide nanocrystals as active materials for hybrid solar cells, due to the good combination of the versatile solution processability of conjugated polymers and high charge carrier mobility of metal-oxide nanocrystals. In this paper, current development of hybrid solar cells worldwide and future research challenges in Indonesia will be discussed.

  5. Workshop on hybrid rice

    Institute of Scientific and Technical Information of China (English)

    TANZhijun

    1994-01-01

    FAO, in collaboration with FEDEARROZ in Colombia and EMBRAPA / CNPAF in Brail, organized a workshop on the Establishment of a Coorperative Research Network on Hybrid Rice in Latin America and the Caribbean held from Mar 16 to 18, 1994 at EMBRAPA/CNPAF in Brazil. Dr MAO Changxiang,

  6. 混合场景中光照一致性研究%Research of illumination consistency in hybrid scene

    Institute of Scientific and Technical Information of China (English)

    叶东文; 陈国栋

    2015-01-01

    在基于本地与远程绘制的混合场景中,为了实现本地绘制场景与远程绘制场景的无缝融合,光照一致性是必须解决的问题。在服务器端绘制所需的复杂背景,在移动终端绘制交互对象,并在场景中使用相同的光照模型。在融合阶段利用服务器端所传递的光照参数对本地移动终端的光照模型进行光照重计算。利用时间插值的方法来模拟一天中环境光的变化情况,并对本地移动终端中的光照模型进行二次重计算。实验结果表明,通过上述方法,在移动终端上实现了不同场景的无缝融合。该方法用于移动终端的场景融合时具有较高的绘制效率与可行性。%Illumination consistency is a problem that must be addressed to reach the seamless integration of local rendering scene and remote rendering scene in a hybrid scene of local and remote rendering.This paper was aim to address the illumina-tion consistency problem.Firstly,it drawn the complex background on the server and drawn the interactive objects on the mo-bile terminal.While drawing the same illumination model was used.Secondly,it used the illumination parameters transmitted by the server to recalculate the illumination parameters for the illumination model on the local mobile terminal in the integration phase.Lastly,used the time interpolation method to simulate the changes of the ambient light during the day and recalculate the illumination model on the local mobile terminal.The experimental results show that,through the above method,the seamless in-tegration of scene can be realized on the mobile terminal.The mothed used for the integration of scene has the high rendering efficiency and feasibility.

  7. Transcriptome analysis of mouse stem cells and early embryos.

    Directory of Open Access Journals (Sweden)

    Alexei A Sharov

    2003-12-01

    Full Text Available Understanding and harnessing cellular potency are fundamental in biology and are also critical to the future therapeutic use of stem cells. Transcriptome analysis of these pluripotent cells is a first step towards such goals. Starting with sources that include oocytes, blastocysts, and embryonic and adult stem cells, we obtained 249,200 high-quality EST sequences and clustered them with public sequences to produce an index of approximately 30,000 total mouse genes that includes 977 previously unidentified genes. Analysis of gene expression levels by EST frequency identifies genes that characterize preimplantation embryos, embryonic stem cells, and adult stem cells, thus providing potential markers as well as clues to the functional features of these cells. Principal component analysis identified a set of 88 genes whose average expression levels decrease from oocytes to blastocysts, stem cells, postimplantation embryos, and finally to newborn tissues. This can be a first step towards a possible definition of a molecular scale of cellular potency. The sequences and cDNA clones recovered in this work provide a comprehensive resource for genes functioning in early mouse embryos and stem cells. The nonrestricted community access to the resource can accelerate a wide range of research, particularly in reproductive and regenerative medicine.

  8. Transcriptome Analysis of Mouse Stem Cells and Early Embryos

    Science.gov (United States)

    Sharov, Alexei A; Piao, Yulan; Matoba, Ryo; Dudekula, Dawood B; Qian, Yong; VanBuren, Vincent; Falco, Geppino; Martin, Patrick R; Stagg, Carole A; Bassey, Uwem C; Wang, Yuxia; Carter, Mark G; Hamatani, Toshio; Aiba, Kazuhiro; Akutsu, Hidenori; Sharova, Lioudmila; Tanaka, Tetsuya S; Kimber, Wendy L; Yoshikawa, Toshiyuki; Jaradat, Saied A; Pantano, Serafino; Nagaraja, Ramaiah; Boheler, Kenneth R; Taub, Dennis; Hodes, Richard J; Longo, Dan L; Schlessinger, David; Keller, Jonathan; Klotz, Emily; Kelsoe, Garnett; Umezawa, Akihiro; Vescovi, Angelo L; Rossant, Janet; Kunath, Tilo; Hogan, Brigid L. M; Curci, Anna; D'Urso, Michele; Kelso, Janet; Hide, Winston

    2003-01-01

    Understanding and harnessing cellular potency are fundamental in biology and are also critical to the future therapeutic use of stem cells. Transcriptome analysis of these pluripotent cells is a first step towards such goals. Starting with sources that include oocytes, blastocysts, and embryonic and adult stem cells, we obtained 249,200 high-quality EST sequences and clustered them with public sequences to produce an index of approximately 30,000 total mouse genes that includes 977 previously unidentified genes. Analysis of gene expression levels by EST frequency identifies genes that characterize preimplantation embryos, embryonic stem cells, and adult stem cells, thus providing potential markers as well as clues to the functional features of these cells. Principal component analysis identified a set of 88 genes whose average expression levels decrease from oocytes to blastocysts, stem cells, postimplantation embryos, and finally to newborn tissues. This can be a first step towards a possible definition of a molecular scale of cellular potency. The sequences and cDNA clones recovered in this work provide a comprehensive resource for genes functioning in early mouse embryos and stem cells. The nonrestricted community access to the resource can accelerate a wide range of research, particularly in reproductive and regenerative medicine. PMID:14691545

  9. Somatic embryogenesis from zygotic embryos of Euterpe oleracea Mart.

    Directory of Open Access Journals (Sweden)

    Ledo Ana da Silva

    2002-01-01

    Full Text Available The aim of this work was to study the morphogenetic responses of zygotic embryos of açai palm (Euterpe oleracea Mart. submitted to several conditions of in vitro culture. Several research experiments were conducted, in laboratory, using vegetable material collected from açai palm plants at Embrapa Amazon Oriental, Belém-PA, Brazil. It was possible to verify the expression of a direct, repetitive and no-synchronized model of somatic embryogenesis in mature zygotic embryos cultivated in primary MS medium supplemented with 2,4-D (339.36 muM and transferred to a secondary MS medium in the presence of NAA (0.537 muM and 2iP (12.30 muM. The conversion of somatic embryos into seedlings was reached after 210 days with the transfer of the cultures to a third medium with sucrose and mineral salts concentrations reduced to a half, without growth regulators.

  10. The fate of the mosaic embryo : chromosomal constitution and development of Day 4, 5 and 8 human embryos

    NARCIS (Netherlands)

    Santos, Margarida Avo; Teklenburg, Gijs; Macklon, Nick S.; Van Opstal, Diane; Schuring-Blom, G. Heleen; Krijtenburg, Pieter-Jaap; de Vreeden-Elbertse, Johanna; Fauser, Bart C.; Baart, Esther B.

    2010-01-01

    Post-zygotic chromosome segregation errors are very common in human embryos after in vitro fertilization, resulting in mosaic embryos. However, the significance of mosaicism for the developmental potential of early embryos is unknown. We assessed chromosomal constitution and development of embryos f

  11. Culture systems: embryo culture and monozygotic twinning.

    Science.gov (United States)

    Sparks, Amy E

    2012-01-01

    The incidence of monozygotic twinning in pregnancies achieved with assisted reproductive technologies (ART) is significantly higher than spontaneously conceived pregnancies. The factors associated with ART that predispose the embryos to splitting are not well-characterized. Assisted hatching and extended embryo culture are two ART laboratory methods that have been risk factors for monozygotic twinning. The methods and strategies that may be employed to avoid monozygotic twinning are discussed in this chapter.

  12. In-vivo Centrifugation of Drosophila Embryos

    OpenAIRE

    Tran, Susan L.; Welte, Michael A.

    2010-01-01

    A major strategy for purifying and isolating different types of intracellular organelles is to separate them from each other based on differences in buoyant density. However, when cells are disrupted prior to centrifugation, proteins and organelles in this non-native environment often inappropriately stick to each other. Here we describe a method to separate organelles by density in intact, living Drosophila embryos. Early embryos before cellularization are harvested from population cages, an...

  13. Generation of Transgenic Hydra by Embryo Microinjection

    Science.gov (United States)

    Juliano, Celina E.; Lin, Haifan; Steele, Robert E.

    2014-01-01

    As a member of the phylum Cnidaria, the sister group to all bilaterians, Hydra can shed light on fundamental biological processes shared among multicellular animals. Hydra is used as a model for the study of regeneration, pattern formation, and stem cells. However, research efforts have been hampered by lack of a reliable method for gene perturbations to study molecular function. The development of transgenic methods has revitalized the study of Hydra biology1. Transgenic Hydra allow for the tracking of live cells, sorting to yield pure cell populations for biochemical analysis, manipulation of gene function by knockdown and over-expression, and analysis of promoter function. Plasmid DNA injected into early stage embryos randomly integrates into the genome early in development. This results in hatchlings that express transgenes in patches of tissue in one or more of the three lineages (ectodermal epithelial, endodermal epithelial, or interstitial). The success rate of obtaining a hatchling with transgenic tissue is between 10% and 20%. Asexual propagation of the transgenic hatchling is used to establish a uniformly transgenic line in a particular lineage. Generating transgenic Hydra is surprisingly simple and robust, and here we describe a protocol that can be easily implemented at low cost. PMID:25285460

  14. Hybrid intermediaries

    OpenAIRE

    Cetorelli, Nicola

    2014-01-01

    I introduce the concept of hybrid intermediaries: financial conglomerates that control a multiplicity of entity types active in the "assembly line" process of modern financial intermediation, a system that has become known as shadow banking. The complex bank holding companies of today are the best example of hybrid intermediaries, but I argue that financial firms from the "nonbank" space can just as easily evolve into conglomerates with similar organizational structure, thus acquiring the cap...

  15. Hybrid composites

    CSIR Research Space (South Africa)

    Jacob John, Maya

    2009-04-01

    Full Text Available effect was observed for the elongation at break of the hybrid composites. The impact strength of the hybrid composites increased with the addition of glass fibres. The tensile and impact properties of thermoplastic natural rubber reinforced short... panels made from conventional structural materials. Figure 3 illustrates the performance of cellular biocomposite panels against conventional systems used for building and residential construction, namely a pre- cast pre-stressed hollow core concrete...

  16. Toward embedded laboratory automation for smart Lab-on-a-Chip embryo arrays.

    Science.gov (United States)

    Wang, Kevin I-Kai; Salcic, Zoran; Yeh, Johnny; Akagi, Jin; Zhu, Feng; Hall, Chris J; Crosier, Kathryn E; Crosier, Philip S; Wlodkowic, Donald

    2013-10-15

    Lab-on-a-Chip (LOC) biomicrofluidic technologies are rapidly emerging bioanalytical tools that can miniaturize and revolutionize in situ research on embryos of small vertebrate model organisms such as zebrafish (Danio rerio) and clawed African frog (Xenopus laevis). Despite considerable progress being made in fabrication techniques of chip-based devices, they usually still require excessive and manual actuation and data acquisition that significantly reduce throughput and introduce operator-related analytical bias. This work describes the development of a proof-of-concept embedded platform that integrates an innovative LOC zebrafish embryo array technology with an electronic interface to provide higher levels of laboratory automation for in situ biotests. The integrated platform was designed to perform automatic immobilization, culture and treatment of developing zebrafish embryos during fish embryo toxicity (FET) biotests. The system was equipped with a stepper motor driven stage, solenoid-actuated pinch valves, miniaturized peristaltic pumps as well as Peltier heating module. Furthermore, a Field Programmable Gate Array (FPGA) was used to implement an embedded hardware/software solution and interface to enable real-time control over embryo loading and immobilization; accurate microfluidic flow control; temperature stabilization and also automatic time-resolved image acquisition of developing zebrafish embryos. This work presents evidence that integration of embedded electronic interfaces with microfluidic chip-based technologies can bring the Lab-on-a-Chip a step closer to fully automated analytical systems.

  17. A system for investigation of biological effects of diagnostic ultrasound on development of zebrafish embryos.

    Science.gov (United States)

    Miller, Douglas L; Zhou, Weibin

    2013-12-01

    A system for scanning zebrafish embryos with diagnostic ultrasound was developed for research into possible biological effects during development. Two troughs for holding embryos were formed from agarose in a rectangular dish and separated by an ultrasound absorber. A 4.9 MHz linear array ultrasound probe was positioned to uniformly scan all the embryos at the bottom of one trough, with the other used for controls. Zebrafish embryos were scanned continuously from 10-24 h post fertilization (hpf) during the segmentation period and gross morphological parameters were measured at 30 hpf, including viability, length, number of visible axons, and the progression of the lateral line primordium (LLP). Our initial tests were encumbered by the thermal effects of probe self-heating, which resulted in accelerated development of the zebrafish embryos. After subsequent optimization, our test revealed a significant retardation of primary motor axons and the migration of the LLP in embryos scanned with ultrasound, which indicated a potential for nonthermal effects on neuronal development. This diagnostic ultrasound exposure system is suitable for further investigation of possible subtle bioeffects, such as perturbation of neuronal migration.

  18. Forebrain neurogenesis: From embryo to adult

    Science.gov (United States)

    Dennis, Daniel; Picketts, David; Slack, Ruth S.; Schuurmans, Carol

    2017-01-01

    A satellite symposium to the Canadian Developmental Biology Conference 2016 was held on March 16–17, 2016 in Banff, Alberta, Canada, entitled Forebrain Neurogenesis: From embryo to adult. The Forebrain Neurogenesis symposium was a focused, high-intensity meeting, bringing together the top Canadian and international researchers in the field. This symposium reported the latest breaking news, along with ‘state of the art’ techniques to answer fundamental questions in developmental neurobiology. Topics covered ranged from stem cell regulation to neurocircuitry development, culminating with a session focused on neuropsychiatric disorders. Understanding the underlying causes of neurodevelopmental disorders such as autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD) is of great interest as diagnoses of these conditions are climbing at alarming rates. For instance, in 2012, the Centers for Disease Control reported that the prevalence rate of ASD in the U.S. was 1 in 88; while more recent data indicate that the number is as high as 1 in 68 (Centers for Disease Control and Prevention MMWR Surveillance Summaries. Vol. 63. No. 2). Similarly, the incidence of ASD is on the rise in Canada, increasing from 1 in 150 in 2000 to 1 in 63 in 2012 in southeastern Ontario (Centers for Disease Control and Prevention). Currently very little is known regarding the deficits underlying these neurodevelopmental conditions. Moreover, the development of effective therapies is further limited by major gaps in our understanding of the fundamental processes that regulate forebrain development and adult neurogenesis. The Forebrain Neurogenesis satellite symposium was thus timely, and it played a key role in advancing research in this important field, while also fostering collaborations between international leaders, and inspiring young researchers.

  19. Why two arguments from probability fail and one argument from Thomson's analogy of the violinist succeeds in justifying embryo destruction in some situations.

    Science.gov (United States)

    Deckers, J

    2007-03-01

    The scope of embryo research in the UK has been expanded by the Human Fertilisation and Embryology (Research Purposes) Regulations 2001. Two advisory bodies--the Chief Medical Officer's Expert Group and the House of Lords' Select Committee--presented various arguments in favour of embryo research. One of these is the view that, just as lottery tickets have relatively little value before the draw because of the low probability of their being the winning ticket, early embryos have relatively little value because of the presumed low probability that they will mature into more developed embryos. This (first) argument from probability is questioned in this paper, as well as the contention that allowing embryo destruction is incompatible with the view that embryos have full moral status. Although I challenge Savulescu's view that early embryos should be entered into a lottery in which they are subjected to the probability of being destroyed (the second argument from probability), a revised version of Thomson's analogy of the famous violinist defies the view that the position that the embryo has full moral status is incompatible with qualified support for embryo destruction.

  20. Zebrafish embryo model of Bartonella henselae infection.

    Science.gov (United States)

    Lima, Amorce; Cha, Byeong J; Amin, Jahanshah; Smith, Lisa K; Anderson, Burt

    2014-10-01

    Bartonella henselae (Bh) is an emerging zoonotic pathogen that has been associated with a variety of human diseases, including bacillary angiomatosis that is characterized by vasoproliferative tumor-like lesions on the skin of some immunosuppressed individuals. The study of Bh pathogenesis has been limited to in vitro cell culture systems due to the lack of an animal model. Therefore, we wanted to investigate whether the zebrafish embryo could be used to model human infection with Bh. Our data showed that Tg(fli1:egfp)(y1) zebrafish embryos supported a sustained Bh infection for 7 days with >10-fold bacterial replication when inoculated in the yolk sac. We showed that Bh recruited phagocytes to the site of infection in the Tg(mpx:GFP)uwm1 embryos. Infected embryos showed evidence of a Bh-induced angiogenic phenotype and an increase in the expression of genes encoding pro-inflammatory factors and pro-angiogenic markers. However, infection of zebrafish embryos with a deletion mutant in the major adhesin (BadA) resulted in little or no bacterial replication and a diminished host response, providing the first evidence that BadA is critical for in vivo infection. Thus, the zebrafish embryo provides the first practical model of Bh infection that will facilitate efforts to identify virulence factors and define molecular mechanisms of Bh pathogenesis.

  1. Advanced Digital Signal Processing for Hybrid Lidar

    Science.gov (United States)

    2014-10-30

    Technical 4. TITLE AND SUBTITLE Advance Digital Signal Processing for Hybrid Lidar 6. AUTHOR(S) William D. Jemison 7. PERFORMING ORGANIZATION NAME(S...development of signed processing algorithms for hybrid lidar - radar designed to improve detection performance. 15. SUBJECT TERMS Hybrid Lidar - Radar 16...Award Number N000141110371 Title of Research Advanced Digital Signal Processing for Hybrid Lidar Principal Investigator William D. Jemison

  2. Human embryo twinning with applications in reproductive medicine.

    Science.gov (United States)

    Illmensee, Karl; Levanduski, Mike; Vidali, Andrea; Husami, Nabil; Goudas, Vasilios T

    2010-02-01

    To assess the efficacy of human embryo twinning by blastomere biopsy at different early embryonic stages (splitting efficiency) and to determine the in vitro developmental capacity of twinned human embryos (developmental efficiency). Randomized comparative study. Private IVF centers. Couples undergoing IVF donating triploid embryos. Embryos at the 2- to 5- and 6- to 8-cell stage were split into twin embryos. Half the number of blastomeres from donor embryos were removed and inserted into recipient empty zonae pellucidae. After embryo splitting, donor and recipient embryos were cultured in vitro. Development of twinned embryos to the blastocyst stage. The number of developing embryos obtained after splitting could be increased in comparison with the number of embryos available before splitting at the 6- to 8-cell stage but not at the 2- to 5-cell stage (splitting efficiency). Splitting of 6- to 8-cell embryos yielded superior rates of twin embryos developing to blastocysts (developmental efficiency). Twinning success was related to the superior morphological quality of embryos used for splitting. This is the first report on twinned human embryos developing to blastocysts. This study exhibits the potential for novel applications in human assisted reproduction. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  3. Toyota hybrid synergy drive

    Energy Technology Data Exchange (ETDEWEB)

    Gautschi, H.

    2008-07-01

    This presentation made at the Swiss 2008 research conference on traffic by Hannes Gautschi, director of service and training at the Toyota company in Switzerland, takes a look at Toyota's hybrid drive vehicles. The construction of the vehicles and their combined combustion engines and electric generators and drives is presented and the combined operation of these components is described. Braking and energy recovery are discussed. Figures on the performance, fuel consumption and CO{sub 2} output of the hybrid vehicles are compared with those of conventional vehicles.

  4. Toyota hybrid synergy drive

    Energy Technology Data Exchange (ETDEWEB)

    Gautschi, H.

    2008-07-01

    This presentation made at the Swiss 2008 research conference on traffic by Hannes Gautschi, director of service and training at the Toyota company in Switzerland, takes a look at Toyota's hybrid drive vehicles. The construction of the vehicles and their combined combustion engines and electric generators and drives is presented and the combined operation of these components is described. Braking and energy recovery are discussed. Figures on the performance, fuel consumption and CO{sub 2} output of the hybrid vehicles are compared with those of conventional vehicles.

  5. Comparison of pregnancy rate between fresh embryo transfers and frozen-thawed embryo transfers following ICSI treatment

    Directory of Open Access Journals (Sweden)

    Zahra Basirat

    2016-01-01

    Full Text Available Background: The use of assisted reproductive technology (ART is increasing in the world. The rate, efficacy and safety of ART are very different among countries. There is an increase in the use of intra cytoplasmic sperm injection (ICSI, single fresh embryo transfer (ET and frozen-thawed embryo transfer (FET. Objective: The objective of this study was to compare pregnancy rate in fresh ET and FET. Materials and Methods: In this retrospective cross-sectional study 1014 ICSI-ET cycles (426 fresh ET and 588 FET from 753 women undergoing ICSI treatment referred to Fatemezahra Infertility and Reproductive Health Research Center in Babol, Iran from 2008 to 2013 were reviewed. Results: There were no significant differences between biochemical pregnancy rate (23% versus 18.8%, OR 1.301; 95% CI .95-1.774, gestational sac (95.6% versus 100% in FET, OR 0.60; 95% CI 0.54-0.67, and fetal heart activity (87.2% versus 93.6% OR .46; 95% CI .16-1.32 in fresh ET and FET cycles, respectively. P< 0.05 was considered statistically significant for all measures. Conclusion: Although, the result showed no significantly difference between the fresh ET and the FET cycles, however the embryos are able to be stored for subsequent ART. Therefore, we recommend FET cycles as an option alongside the fresh ET.

  6. Predictive Battery Management System for Commercial Hybrid Vehicles: Cooperative Research and Development Final Report, CRADA Number CRD-13-520

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Kandler [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-08-01

    NREL and Eaton Corporation will perform work together on DOE Advanced Research Projects Agency-Energy (ARPA-E) 'Advanced Management and Protection of Energy Storage Devices' program (DE-FOA0000675). NREL will experimentally characterize aging behavior of Eaton cells and packs. Eaton and NREL will implement NREL's prognostic life model in Eaton HEV supervisory controllers and demonstrate the algorithms in accelerated life hardware-in-the loop testing conducted at NREL.

  7. Speciation and reduced hybrid female fertility in house mice.

    Science.gov (United States)

    Suzuki, Taichi A; Nachman, Michael W

    2015-09-01

    In mammals, intrinsic postzygotic isolation has been well studied in males but has been less studied in females, despite the fact that female gametogenesis and pregnancy provide arenas for hybrid sterility or inviability that are absent in males. Here, we asked whether inviability or sterility is observed in female hybrids of Mus musculus domesticus and M. m. musculus, taxa which hybridize in nature and for which male sterility has been well characterized. We looked for parent-of-origin growth phenotypes by measuring adult body weights in F1 hybrids. We evaluated hybrid female fertility by crossing F1 females to a tester male and comparing multiple reproductive parameters between intrasubspecific controls and intersubspecific hybrids. Hybrid females showed no evidence of parent-of-origin overgrowth or undergrowth, providing no evidence for reduced viability. However, hybrid females had smaller litter sizes, reduced embryo survival, fewer ovulations, and fewer small follicles relative to controls. Significant variation in reproductive parameters was seen among different hybrid genotypes, suggesting that hybrid incompatibilities are polymorphic within subspecies. Differences in reproductive phenotypes in reciprocal genotypes were observed and are consistent with cyto-nuclear incompatibilities or incompatibilities involving genomic imprinting. These findings highlight the potential importance of reduced hybrid female fertility in the early stages of speciation.

  8. Selection of in vitro produced, transgenic embryos by nested PCR for efficient production of transgenic goats.

    Science.gov (United States)

    Huang, S Z; Huang, Y; Chen, M J; Zeng, F Y; Ren, Z R; Zeng, Y T

    2001-09-01

    The production of valuable pharmaceutical proteins using transgenic animals as bioreactors has become one of the goals of biotechnology. However, the efficiency of producing transgenic animals by means of pronuclear microinjection is low. This may be attributed in part to the low integration rate of foreign DNA. Therefore, a large number of recipients are required to produce transgenic animals. We recently developed a transgenic procedure that combined the techniques of goat oocyte in vitro maturation (IVM), in vitro fertilization (IVF), microinjection, preimplantation selection of the transgenic embryos with nested PCR and transferring the transgenic embryos into the recipient goat uterus to produce transgenic goats. Thirty-seven transgenic embryos determined by nested PCR were transferred to thirty-two recipient goats. In the end, four live-born kids were produced. As predicted, all the live kids were transgenic as identified by PCR as well as Southern blot hybridization, The integration rate was 100% (4/4) which was completely in accordance with the results of embryo preimplantation detection. The results showed a significant decrease in the number of recipients required as only 8 recipients (32/4) were needed to obtain one live transgenic goat. We suggest that the transgenic system described herein may provide an improved way to efficiently produce transgenic goats on a large scale.

  9. Transcription of ribosomal RNA genes is initiated in the third cell cycle of bovine embryos

    DEFF Research Database (Denmark)

    Jakobsen, Anne Sørig; Avery, Birthe; Dieleman, Steph J.

    2006-01-01

    of the embryonic genome. In the present study, ribosomal RNA (rRNA) transcription was investigated by visualization of the rRNA by fluorescent in situ hybridization, and subsequent visualization of the argyrophilic nucleolar proteins by silver staining. A total of 145 in vivo developed and 200 in vitro produced...... bovine embryos were investigated to allow comparison of transcription initiation. Signs of active transcription of rRNA were observed in the third cell cycle in 29% of the in vitro produced embryos (n=35) and in 58% of the in vivo developed embryos (n=11). Signs of active transcription of rRNA were...... not apparent in the early phase of the fourth cell cycle but restarted later on. All embryos in the fifth or later cell cycles were all transcribing rRNA. The signs of rRNA synthesis during the third and fourth embryonic cell cycles could be blocked by actinomycin D, which is a strong inhibitor of RNA...

  10. The parental origin correlates with the karyotype of human embryos developing from tripronuclear zygotes.

    Science.gov (United States)

    Joergensen, Mette Warming; Labouriau, Rodrigo; Hindkjaer, Johnny; Stougaard, Magnus; Kolevraa, Steen; Bolund, Lars; Agerholm, Inge Errebo; Sunde, Lone

    2015-03-01

    It has previously been suggested that embryos developing from intracytoplasmic sperm-injected (ICSI) zygotes with three pronuclei (3PN) are endowed with a mechanism for self-correction of triploidy to diploidy. 3PN are also observed in zygotes after conventional in vitro fertilization (IVF). The parental origin, however, differs between the two fertilization methods. Whereas the vast majority of 3PN IVF zygotes are of dispermic origin and thus more likely to have two centrioles, the 3PN ICSI zygotes are digynic in origin and therefore, more likely to have one centriole. In the present study, we examine whether the parental origin of 3PN embryos correlates with the karyotype. The karyotype of each nucleus was estimated using four sequential fluorescence in situ hybridizations-each with two probes-resulting in quantitative information of 8 different chromosomes. The karyotypes were then compared and correlated to the parental origin. 3PN ICSI embryos displayed a significantly larger and more coordinated reduction from the assumed initial 3 sets of chromosomes than 3PN IVF embryos. The differences in the parental origin-and hence the number of centrioles-between the 3PN IVF and the 3PN ICSI zygotes are likely to be the cause of the differences in karyotypes.

  11. The Effect of Prolonged Culture of Chromosomally Abnormal Human Embryos on The Rate of Diploid Cells

    Directory of Open Access Journals (Sweden)

    Masood Bazrgar

    2016-12-01

    Full Text Available Background: A decrease in aneuploidy rate following a prolonged co-culture of human blastocysts has been reported. As co-culture is not routinely used in assisted reproductive technology, the present study aimed to evaluate the effect of the prolonged single culture on the rate of diploid cells in human embryos with aneuploidies. Materials and Methods: In this cohort study, we used fluorescence in situ hybridization (FISH to reanalyze surplus blastocysts undergoing preimplantation genetic diagnosis (PGD on day 3 postfertilization. They were randomly studied on days 6 or 7 following fertilization. Results: Of the 30 analyzed blastocysts, mosaicism was observed in 26(86.6%, while 2(6.7% were diploid, and 2(6.7% were triploid. Of those with mosaicism, 23(88.5% were determined to be diploid-aneuploid and 3(11.5% were aneuploid mosaic. The total frequency of embryos with more than 50% diploid cells was 33.3% that was lower on day 7 in comparison with the related value on day 6 (P<0.05; however, there were no differences when the embryos were classified according to maternal age, blastocyst developmental stage, total cell number on day 3, and embryo quality. Conclusion: Although mosaicism is frequently observed in blastocysts, the prolonged single culture of blastocysts does not seem to increase the rate of normal cells.

  12. Miniaturized embryo array for automated trapping, immobilization and microperfusion of zebrafish embryos.

    Directory of Open Access Journals (Sweden)

    Jin Akagi

    Full Text Available Zebrafish (Danio rerio has recently emerged as a powerful experimental model in drug discovery and environmental toxicology. Drug discovery screens performed on zebrafish embryos mirror with a high level of accuracy the tests usually performed on mammalian animal models, and fish embryo toxicity assay (FET is one of the most promising alternative approaches to acute ecotoxicity testing with adult fish. Notwithstanding this, automated in-situ analysis of zebrafish embryos is still deeply in its infancy. This is mostly due to the inherent limitations of conventional techniques and the fact that metazoan organisms are not easily susceptible to laboratory automation. In this work, we describe the development of an innovative miniaturized chip-based device for the in-situ analysis of zebrafish embryos. We present evidence that automatic, hydrodynamic positioning, trapping and long-term immobilization of single embryos inside the microfluidic chips can be combined with time-lapse imaging to provide real-time developmental analysis. Our platform, fabricated using biocompatible polymer molding technology, enables rapid trapping of embryos in low shear stress zones, uniform drug microperfusion and high-resolution imaging without the need of manual embryo handling at various developmental stages. The device provides a highly controllable fluidic microenvironment and post-analysis eleuthero-embryo stage recovery. Throughout the incubation, the position of individual embryos is registered. Importantly, we also for first time show that microfluidic embryo array technology can be effectively used for the analysis of anti-angiogenic compounds using transgenic zebrafish line (fli1a:EGFP. The work provides a new rationale for rapid and automated manipulation and analysis of developing zebrafish embryos at a large scale.

  13. Embryo quality and transcervical technique are not the limiting factors in donkey embryo transfer outcome.

    Science.gov (United States)

    Panzani, D; Rota, A; Crisci, A; Kindahl, H; Govoni, N; Camillo, F

    2012-02-01

    Embryo transfer (ET) in the donkey resulted in a very low recipient pregnancy rates. The aim of these studies was to investigate if nonsurgical transfer techniques or donkey embryo quality affect donkey recipient pregnancy failure. In Study 1, the impact of transfer technique was investigated by evaluating if cervical catheterization is associated with prostaglandin release and suppression of luteal function and if donkey recipients would become pregnant after nonsurgical transfer of horse embryos. Four jennies, from 5 to 8 d after ovulation, were submitted to a sham transcervical ET and to evaluation of PGFM and progesterone plasma concentrations. Five 8 d horse embryos were nonsurgically transferred into synchronized donkey recipients (HD). Cervical stimulation caused a transient PGF(2α) release in two of four jennies in the absence of a significant decrease in progesterone plasma concentration. All transferred horse embryos resulted in pregnancies in the jenny recipients. In Study 2, donkey embryo viability was investigated by 1.2 meters, 6-diamidino-2-phenylindole (DAPI) staining of 10 embryos and by the transfer of 6 and 12 donkey embryos in synchronized mare (DH) and donkey (DD) recipients, respectively, of known fertility. The estimated proportion of dead cells in DAPI stained embryos was 0.9% (range 0-3.9%) and below what is considered normal (20%) for horse embryos. Three of six and six of 12 of the DH and DD ETs, respectively resulted in pregnancies at 14 and 25 d (50%), a higher pregnancy rate than previously reported after DD ET. The overall results of this study suggest that the transcervical technique for ET and donkey embryo viability are not the reasons for the low pregnancy rates that have previously been described in donkey recipients, and that nonsurgical ET in donkeys can result in acceptable results.

  14. Low serum concentration in bovine embryo culture enhances early blastocyst rates on Day-6 with quality traits in the expanded blastocyst stage similar to BSA-cultured embryos.

    Science.gov (United States)

    Murillo, A; Muñoz, M; Martín-González, D; Carrocera, S; Martínez-Nistal, A; Gómez, E

    2017-06-01

    In bovine, single in vitro embryo culture in protein-free medium from Day-6 to Day-7 leads to expanded blastocyst (XB) with improved pregnancy and birth rates after cryopreservation. Under these conditions, early blastocysts (EB) progress to the XB stage at higher rates than morulae (M). However, embryo production with BSA in culture prior to Day-6 leads to low EB rates. We investigated whether a very low FCS concentration (0.1%) in culture from Day-1 to Day-6 would improve EB rates and, subsequently, increase XB rates on Day-7 after single culture in protein-free medium. The quality of embryos produced was evaluated in terms of survival to cryopreservation, apoptosis percentage, lipid accumulation and transfer to recipients. On Day-6, EB rates from embryos cultured with FCS were higher than with BSA (P=0.022). On Day-7, XB rates were higher in embryos from Day-6 EB than from Day-6M, both with and without FCS (Pcultured individually, led to pregnancies after ET. In conclusion, minute FCS concentration improves EB rates on Day-6 leading, after one-day single culture without protein, to more XBs. The quality of XB produced with FCS compares well with XB produced with BSA in terms of apoptosis, lipid accumulation and pregnancy. Copyright © 2017 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  15. Screening of biotechnical parameters for production of bovine inter-subspecies embryonic chimeras by the aggregation of tetraploid Bos indicus and diploid crossbred Bos taurus embryos.

    Science.gov (United States)

    Razza, Eduardo M; Satrapa, Rafael A; Emanuelli, Isabele P; Barros, Ciro M; Nogueira, Marcelo F G

    2016-03-01

    The aggregation of a tetraploid zebu embryo (Bos indicus, a thermotolerant breed) with a diploid taurine embryo (Bos taurus, a thermosensitive breed) should create a complete taurine fetus, whose extra-embryonic components, e.g., the chorion, is derived mainly from the zebu embryo. These zebu-derived extra-embryonic components may interact positively with the taurine embryo/fetus during pregnancy in a tropical environment. We tested different parameters for the production of tetraploid Nelore (Bos indicus) embryos to be combined via aggregation with crossbred Bos taurus (diploid) embryos in order to produce viable chimeric blastocysts. Bovine (Bos indicus or crossbred Bos taurus) embryos were produced in vitro according to standard procedures. Two-cell Bos indicus embryos were submitted to electrofusion with varying numbers of pulses (1 or 2), voltages (0.4, 0.5, 0.75, 1.0, 1.4 and 5.0 kV/cm) and time (20, 25, 50 and 60 μs) to produce tetraploid embryos. Electrofused embryos were cultured with crossbred non-fused embryos to form chimeras that developed until the blastocyst stage. The best fusion parameter was 0.75 kV/cm for 60 μs. Four chimeric blastocysts (tetraploid Nelore with diploid crossbred Holstein) were formed after 31 attempts in 4 replicates (13%). We established an optimal procedure for the production of tetraploid Bos indicus (4n) embryos and embryonic chimeras by aggregation of crossbred Bos taurus (2n) with Bos indicus (4n) embryos. This technique would be valid in applied research, by producing exclusively taurine calves, but with placental elements from the Bos indicus breed, following transfer of these chimeras into recipient cows.

  16. Improving post-transfer survival of bovine embryos produced in vitro: actions of insulin-like growth factor-1, colony stimulating factor-2 and hyaluronan.

    Science.gov (United States)

    Block, J; Hansen, P J; Loureiro, B; Bonilla, L

    2011-12-01

    Technologies for in vitro embryo production have the potential to enhance the efficiency of cattle production systems. However, utilization of in vitro-produced embryos for transfer remains limited throughout much of the world. Despite improvements over the past two decades, problems associated with the production of bovine embryos in vitro still exist which limit the widespread commercial application of this technology. In particular, bovine embryos produced in vitro have a reduced capacity to establish and maintain pregnancy as compared with their in vivo-derived counterparts. Embryo competence for survival following transfer is improved by in vivo culture in the sheep oviduct, thus indicating that standard embryo culture conditions are sub-optimal. Therefore, one strategy to improve post-transfer survival is to modify embryo culture media to more closely mimic the in vivo microenvironment. The maternal environment in which the bovine embryo develops in vivo contains various growth factors, cytokines, hormones, and other regulatory molecules. In addition to affecting bovine embryo development in vitro, recent research indicates that embryo competence for survival following transfer can also be improved when such molecules are added to embryo culture medium. Among the specific molecules that can increase post-transfer embryo survival are insulin-like growth factor-1 (IGF-1), colony stimulating factor-2 (CSF-2) and hyaluronan. This paper will review the effects IGF-1, CSF-2 and hyaluronan on post-culture embryo viability and discuss the potential mechanisms through which each of these molecules improves post-transfer survival. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. A Hybrid Integrated Laboratory and Inquiry-Based Research Experience: Replacing Traditional Laboratory Instruction with a Sustainable Student-Led Research Project

    Science.gov (United States)

    Hartings, Matthew R.; Fox, Douglas M.; Miller, Abigail E.; Muratore, Kathryn E.

    2015-01-01

    The Department of Chemistry at American University has replaced its junior- and senior-level laboratory curriculum with two, two-semester long, student-led research projects as part of the department's American Chemical Society-accredited program. In the first semester of each sequence, a faculty instructor leads the students through a set of…

  18. Ploidy Variation in Hybrids from Interploid 3x X 2x Crosses in Musa

    OpenAIRE

    Osuji, JO.; Vuylsteke, D.; Ortiz, R.

    1997-01-01

    Hybrids were obtained after in vitro germination of embryos from interploid crosses between triploid 'French' plantain cultivars (Musa spp. AAB group) 'Ntanga 2' and 'Bobby Tannap' with diploid banana (Ivlusa acuminata subsp. burmannicoidesj 'Calcutta 4'. Cross-pollinated bunches were harvested at full maturity and ripened with acetylene in a room for 4 days. Seeds were extracted from peeled ripe fruits by squashing. Embryos from the seeds were excised aseptically after 2 days and germinated ...

  19. Expression of proposed implantation marker genes CDX2 and HOXB7 in the blastocyst does not distinguish viable from non-viable human embryos

    DEFF Research Database (Denmark)

    Kirkegaard, Kirstine; Hindkjær, Johnny Juhl; Ingerslev, Hans Jakob

    2012-01-01

    Introduction: Selection of the most competent embryo challenges the credo of promoting single embryo transfer (SET) while maintaining high pregnancy rates, thus intensifying the need to introduce techniques that can improve embryo selection. Recent studies have demonstrated that blastocyst gene....... After 4-5 hours of continued culture 5-10 herniating TE cells were aspirated into a biopsy pipette and dissected free of the blastocyst mass using a laser (ZilosTM, Hamilton Thorne Research, wavelength 1480 nm). Biopsied embryos were cultured overnight prior to re-assessment and transfer early on day 6...

  20. Research on inverse, hybrid and optimization problems in engineering sciences with emphasis on turbomachine aerodynamics: Review of Chinese advances

    Science.gov (United States)

    Liu, Gao-Lian

    1991-01-01

    Advances in inverse design and optimization theory in engineering fields in China are presented. Two original approaches, the image-space approach and the variational approach, are discussed in terms of turbomachine aerodynamic inverse design. Other areas of research in turbomachine aerodynamic inverse design include the improved mean-streamline (stream surface) method and optimization theory based on optimal control. Among the additional engineering fields discussed are the following: the inverse problem of heat conduction, free-surface flow, variational cogeneration of optimal grid and flow field, and optimal meshing theory of gears.

  1. Application of in situ Hybridization in Plant Molecular Cytogenetics Research%DNA分子原位杂交(in situ hybridization)在植物分子细胞遗传学研究中的应用

    Institute of Scientific and Technical Information of China (English)

    别同德; 张伯桥; 高德荣; 程顺和; 马谈斌

    2008-01-01

    DNA分子原位杂交(in situ hybridization,ISH)是植物分子细胞遗传学研究的重要工具.简要回顾了DNA分子原位杂交的起源和发展,详细综述了基因组原位杂交(genomic in situ hybridization, GISH)在植物细胞遗传学研究中的应用以及荧光原位杂交(Fluorescence in situ hybridization, FISH)在植物物理作图和染色体识别中的应用.还介绍了Fiber-FISH、BAC-FISH以及Immuno-FISH等新兴技术,最后对FISH技术进行了展望.

  2. A novel hybrid MCDM model for performance evaluation of research and technology organizations based on BSC approach.

    Science.gov (United States)

    Varmazyar, Mohsen; Dehghanbaghi, Maryam; Afkhami, Mehdi

    2016-10-01

    Balanced Scorecard (BSC) is a strategic evaluation tool using both financial and non-financial indicators to determine the business performance of organizations or companies. In this paper, a new integrated approach based on the Balanced Scorecard (BSC) and multi-criteria decision making (MCDM) methods are proposed to evaluate the performance of research centers of research and technology organization (RTO) in Iran. Decision-Making Trial and Evaluation Laboratory (DEMATEL) are employed to reflect the interdependencies among BSC perspectives. Then, Analytic Network Process (ANP) is utilized to weight the indices influencing the considered problem. In the next step, we apply four MCDM methods including Additive Ratio Assessment (ARAS), Complex Proportional Assessment (COPRAS), Multi-Objective Optimization by Ratio Analysis (MOORA), and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) for ranking of alternatives. Finally, the utility interval technique is applied to combine the ranking results of MCDM methods. Weighted utility intervals are computed by constructing a correlation matrix between the ranking methods. A real case is presented to show the efficacy of the proposed approach.

  3. Meanings of the embryo in Japan: narratives of IVF experience and embryo ownership

    NARCIS (Netherlands)

    Kato, M.; Sleeboom-Faulkner, M.

    2011-01-01

    This article explores the sociocultural meanings of the embryo implied in the narratives of 58 women who have undergone in vitro fertilisation in Japan over a period from 2006 to 2008. We argue that a lack of sufficient analysis of the sociocultural meanings of the embryo result in a situation where

  4. Meanings of the embryo in Japan: narratives of IVF experience and embryo ownership.

    Science.gov (United States)

    Kato, Masae; Sleeboom-Faulkner, Margaret

    2011-03-01

    This article explores the sociocultural meanings of the embryo implied in the narratives of 58 women who have undergone in vitro fertilisation in Japan over a period from 2006 to 2008. We argue that a lack of sufficient analysis of the sociocultural meanings of the embryo result in a situation where the use of reproductive technologies in Japan advances without reflecting upon the voices of women and couples that use them. Additionally, we argue that the often-heard view that pre-implantation genetic diagnosis causes less pain to women and couples than selective abortion in which foetuses are discarded, should be reviewed in the light of the new empirical evidence offered in this article. Furthermore, this article shows that the view often expounded by Japanese scientists that in Japan the cultural meanings attached to the embryo are insignificant, is incorrect. Consequently, the argument that Japan has no need for an active national debate on the status of embryos should be questioned. Though agreeing with some feminist views on the embryo debate, this article is also critical of feminist views that discuss embryo donation in terms of the loss of ownership of the embryo and the alienation of the embryo due to commodification. © 2011 The Authors. Journal compilation © 2011 Foundation for the Sociology of Health & Illness/Blackwell Publishing Ltd.

  5. Meanings of the embryo in Japan: narratives of IVF experience and embryo ownership

    NARCIS (Netherlands)

    Kato, M.; Sleeboom-Faulkner, M.

    2011-01-01

    This article explores the sociocultural meanings of the embryo implied in the narratives of 58 women who have undergone in vitro fertilisation in Japan over a period from 2006 to 2008. We argue that a lack of sufficient analysis of the sociocultural meanings of the embryo result in a situation where

  6. Hybrid Lethal Systems in the Drosophila Melanogaster Species Complex. I. the Maternal Hybrid Rescue (Mhr) Gene of Drosophila Simulans

    Science.gov (United States)

    Sawamura, K.; Taira, T.; Watanabe, T. K.

    1993-01-01

    Hybrid females from Drosophila simulans females X Drosophila melanogaster males die as embryos while hybrid males from the reciprocal cross die as late larvae. The other two classes are sterile adults. Letting C, X, and Y designate egg cytoplasm, X, and Y chromosomes, respectively, and subscripts m and s stand for melanogaster and simulans, C(m)X(m)Y(s) males are lethal in the larval stage and are rescued by the previously reported genes, Lhr (Lethal hybrid rescue) in simulans or Hmr (Hybrid male rescue) in melanogaster. We report here another rescue gene located on the second chromosome of simulans, mhr (maternal hybrid rescue) that, when present in the mother, rescues C(s)X(m)X(s) females from embryonic lethality. It has been postulated that the hybrids not carrying the X(s) like C(m)X(m)Y(s) males are larval lethal and that the hybrids carrying both the C(s) and the X(m) like C(s)X(m)X(s) females are embryonic lethal. According to these postulates C(s)X(m)Y(s) males (obtained by mating attached-X simulans females to melanogaster males) should be doubly lethal, at both embryo and larval stages. When both rescuing genes are present, Hmr in the father and mhr in the mother, males of this genotype are fully viable, as predicted. PMID:8436276

  7. Comparison of the major malformation rate of children conceived from cryopreserved embryos and fresh embryos

    Institute of Scientific and Technical Information of China (English)

    LI Hong-zhen; QIAO Jie; CHI Hong-bin; CHEN Xin-na; LIU Ping; MA Cai-hong

    2010-01-01

    Background Cryopreserved embryo transfer has become indispensable in reproductive technology. More and more children are conceived from frozen-thawed embryo transfer (FET). The risk of birth defects associated with frozen-thawed embryo transfer has been evaluated and conflict results are obtained. The aim of this study was to compare the rate of major malformations in children conceived from cryopreserved embryos with that of children from fresh embryos. Methods A retrospective analysis was performed on children conceived from frozen-thawed embryos and fresh embryos between January 2005 and December 2008 at the Reproduction Center of the Third Hospital, Peking University.The major malformation rates were compared between two groups for all children, as well as singletons or twins,separately. The frequencies of different subtypes of malformations classified according to different organ system were also compared.Results Thirty-four of 3125 children from cryopreserved embryos had a major malformation. The malformation rate was 1.09%, which was comparable to that for children after fresh embryos transfer (1.53%(55/3604), OR:0.71, 95% CI; 0.46-1.09). The malformation rate was also similar when the analysis was limited to children from cryopreserved embryos resulted from in vitro fertilization (IVF)(1.39%)and fresh IVF(1.3%). However, children from cryopreserved embryos resulted from intracytoplasmic sperm injections (ICSI) had much lower malformation rate than from fresh ICSI(0.63% vs.1.83%, OR: 0.34, 95% CI: 0.16-0.75). No difference was found in the incidence of major malformations in singletons from cryo ICSI (0.73%) and fresh ICS1(1.9%), or from cryo IVF(1.49%) and fresh IVF(1.67%). Similar malformation rate was found in multiples from cryo ICSI(0.52%) and fresh ICSI(1.76%), or cryo IVF(1.30%) and fresh IVF(0.90%). The distribution and risk of the subtype of malformations, such as cardiovascular, gastrointestinal, neural tube, urogenital, rnusculoskeletal and facial

  8. Developmental competence of porcine chimeric embryos produced by aggregation

    DEFF Research Database (Denmark)

    Li, Juan; Jakobsen, Jannik E.; Xiong, Qiang

    2015-01-01

    The purpose of our study was to compare the developmental competence and blastomere allocation of porcine chimeric embryos formed by micro-well aggregation. Chimeras were created by aggregating either two blastomeres originating from 2-cell embryos or two whole embryos, where embryos were produced...... either by parthenogenetic activation (PA) or handmade cloning (HMC). Results showed that the developmental competence of chimeric embryos, evaluated based on their blastocyst rate and total cell number per blastocyst, was increased when two whole 2-cell stage embryos (PA or HMC) were aggregated....... In comparison, when two blastomeres were aggregated, the developmental competence of the chimeric embryos decreased if the blastomeres were either from PA or from HMC embryos, but not if they were from different sources, i.e. one PA and one HMC blastomere. To evaluate the cell contribution in embryo formation...

  9. Development of interspecies cloned embryos in yak and dog.

    Science.gov (United States)

    Murakami, Masao; Otoi, Takeshige; Wongsrikeao, Pimprapar; Agung, Budiyanto; Sambuu, Rentsenkhand; Suzuki, Tatsuyuki

    2005-01-01

    Interspecies nuclear transfer (NT) could be an alternative to replicate animals when supply of recipient oocytes is limited or in vitro embryo production systems are incomplete. In the present study, embryonic development was assessed following interspecies NT of donor cumulus cells derived from yak and dog into the recipient ooplasm of domestic cow. The percentages of fusion and subsequent embryo development to the eight-cell stage of interspecies NT embryos were comparable to those of intraspecies NT embryos (cow-cow NT embryos). The percentage of development to blastocysts was significantly lower (p dog-cow NT embryos, only one embryo (0.4%) developed to the blastocyst stage. These results indicate that interspecies NT embryos possess equally developmental competence to the eight-cell stage as intraspecies NT embryos, but the development to blastocysts is very low when dog somatic cells are used as the donor nuclei.

  10. Developmental competence of porcine chimeric embryos produced by aggregation

    DEFF Research Database (Denmark)

    Li, Juan; Jakobsen, Jannik E.; Xiong, Qiang

    2015-01-01

    The purpose of our study was to compare the developmental competence and blastomere allocation of porcine chimeric embryos formed by micro-well aggregation. Chimeras were created by aggregating either two blastomeres originating from 2-cell embryos or two whole embryos, where embryos were produced...... either by parthenogenetic activation (PA) or handmade cloning (HMC). Results showed that the developmental competence of chimeric embryos, evaluated based on their blastocyst rate and total cell number per blastocyst, was increased when two whole 2-cell stage embryos (PA or HMC) were aggregated....... In comparison, when two blastomeres were aggregated, the developmental competence of the chimeric embryos decreased if the blastomeres were either from PA or from HMC embryos, but not if they were from different sources, i.e. one PA and one HMC blastomere. To evaluate the cell contribution in embryo formation...

  11. A Hybrid Multi-Criteria Decision Model for Technological Innovation Capability Assessment: Research on Thai Automotive Parts Firms

    Directory of Open Access Journals (Sweden)

    Sumrit Detcharat

    2013-01-01

    Full Text Available The efficient appraisal of technological innovation capabilities (TICs of enterprises is an important factor to enhance competitiveness. This study aims to evaluate and rank TICs evaluation criteria in order to provide a practical insight of systematic analysis by gathering the qualified experts’ opinions combined with three methods of multi-criteria decision making approach. Firstly, Fuzzy Delphi method is used to screen TICs evaluation criteria from the recent published researches. Secondly, the Analytic Hierarchy Process is utilized to compute the relative important weights. Lastly, the VIKOR method is used to rank the enterprises based on TICs evaluation criteria. An empirical study is applied for Thai automotive parts firms to illustrate the proposed methods. This study found that the interaction between criteria is essential and influences TICs; furthermore, this ranking development of TICs assessment is also one of key management tools to simply facilitate and offer a new mindset for managements of other related industries.

  12. Bovine pretransfer endometrium and embryo transcriptome fingerprints as predictors of pregnancy success after embryo transfer.

    Science.gov (United States)

    Salilew-Wondim, Dessie; Hölker, Michael; Rings, Franca; Ghanem, Nasser; Ulas-Cinar, Mehmet; Peippo, Jaana; Tholen, Ernst; Looft, Christian; Schellander, Karl; Tesfaye, Dawit

    2010-07-07

    Aberrant gene expression in the uterine endometrium and embryo has been the major causes of pregnancy failure in cattle. However, selecting cows having adequate endometrial receptivity and embryos of better developmental competence based on the gene expression pattern has been a greater challenge. To investigate whether pretransfer endometrial and embryo gene expression pattern has a direct relation with upcoming pregnancy success, we performed a global endometrial and embryo transcriptome analysis using endometrial and embryo biopsy technology and the pregnancy outcome information. For this, endometrial samples were collected from Simmental heifers at day 7 and 14 of the estrous cycle, one cycle prior to embryo transfer. In the next cycle, blastocyst stage embryos were transferred to recipients at day 7 of the estrous cycle after taking 30-40% of the blastocyst as a biopsy for transcriptome analysis. The results revealed that at day 7 of the estrous cycle, the endometrial gene expression pattern of heifers whose pregnancy resulting in calf delivery was significantly different compared with those resulting in no pregnancy. These differences were accompanied by qualitative and quantitative alteration of major biological process and molecular pathways. However, the transcriptome difference was minimal between the two groups of animals at day 14 of the estrous cycle. Similarly, the transcriptome analysis between embryos biopsies that resulted in calf delivery and those resulted in no pregnancy revealed a total of 70 differentially expressed genes. Among these, the transcript levels of 32 genes including SPAG17, PF6, UBE2D3P, DFNB31, AMD1, DTNBP1, and ARL8B were higher in embryo biopsies resulting in calf delivery. Therefore, the present study highlights the potential of pretransfer endometrial and embryo gene expression patterns as predictors of pregnancy success in cattle.

  13. Embedding, serial sectioning and staining of zebrafish embryos using JB-4 resin.

    Science.gov (United States)

    Sullivan-Brown, Jessica; Bisher, Margaret E; Burdine, Rebecca D

    2011-01-01

    Histological techniques are critical for observing tissue and cellular morphology. In this paper, we outline our protocol for embedding, serial sectioning, staining and visualizing zebrafish embryos embedded in JB-4 plastic resin-a glycol methacrylate-based medium that results in excellent preservation of tissue morphology. In addition, we describe our procedures for staining plastic sections with toluidine blue or hematoxylin and eosin, and show how to couple these stains with whole-mount RNA in situ hybridization. We also describe how to maintain and visualize immunofluorescence and EGFP signals in JB-4 resin. The protocol we outline-from embryo preparation, embedding, sectioning and staining to visualization-can be accomplished in 3 d. Overall, we reinforce that plastic embedding can provide higher resolution of cellular details and is a valuable tool for cellular and morphological studies in zebrafish.

  14. Passage number affects the pluripotency of mouse embryonic stem cells as judged by tetraploid embryo aggregation.

    Science.gov (United States)

    Li, Xiang-Yun; Jia, Qing; Di, Ke-Qian; Gao, Shu-Min; Wen, Xiao-Hui; Zhou, Rong-Yan; Wei, Wei; Wang, Li-Ze

    2007-03-01

    The aim of this study was to determine whether the number of passages affected the developmental pluripotency of embryonic stem (ES) cells as measured by the attainment of adult fertile mice derived from embryonic stem (ES) cell/tetraploid embryo complementation. Thirty-six newborns were produced by the aggregation of tetraploid embryos and hybrid ES cells after various numbers of passages. These newborns were entirely derived from ES cells as judged by microsatellite DNA, coat-color phenotype, and germline transmission. Although 15 survived to adulthood, 17 died of respiratory failure, and four were eaten by their foster mother. From the 15 mice that reached adulthood and that could reproduce, none arose from ES cells at passage level 15 or more. All 15 arose from cells at passages 3-11. Our results demonstrate that the number of passages affects the developmental pluripotency of ES cells.

  15. Hybrid zone and its genetic analysis: implication for conservation

    Institute of Scientific and Technical Information of China (English)

    ZHENGDong; LIUXue-dong; MAJian-zhang

    2003-01-01

    Hybrid zone is a very critical concept within the evolutionary biology, because it would offer us a better insight to understand the evolutionary role of gene flow and hybridization based on the cline model. This minireview presents an expatia-tion of history perspectives and research developments upon basic concepts including hybrid zones, hybridization, hybrid and its the genetic cline model. Moreover, by figuring out the existing problem around the hybrids within conservative theory and prac-tices, it suggests that the theory of hybrid zone be introduced into conservation biology and it would be provide a broader and more open theoretical background for conservative research and practices.

  16. Generation of targeted mouse mutants by embryo microinjection of TALENs.

    Science.gov (United States)

    Wefers, Benedikt; Ortiz, Oskar; Wurst, Wolfgang; Kühn, Ralf

    2014-08-15

    Gene engineering for generating targeted mouse mutants is a key technology for biomedical research. Using TALENs as nucleases to induce targeted double-strand breaks, the mouse genome can be directly modified in zygotes in a single step, without the need for embryonic stem cells. Thereby, knockout and knockin alleles can be generated fast and efficiently by embryo microinjection of TALEN mRNAs and targeting vectors. In this article we present an introduction into the TALEN technology and provide protocols for the application of TALENs in mouse zygotes.

  17. A Study on the Electromagnet Thrust force Characteristics of Newly Proposed Hybrid Bottom-mounted Control Rod Drive Mechanism for Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Huh, Hyung; Cho, Yeong Garp; Choi, Myoung Hwan; Yu, Je Yong; Kim, Ji Ho; Kim, Jong In [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-05-15

    The control rod drive mechanism (CRDM) is the part of reactor regulating system (RRS), which is located in the reactor pool top (Top-mounted) or the room below the reactor pool (Bottom-mounted). The function of the CRDM is to insert, withdraw or maintain neutron absorbing material at any required position within the reactor core, in order to the reactivity control of the core. There are so many kinds of CRDM, such as magneticjack type, hydraulic type, rack and pinion type, chain type and linear or rotary step motor and so on. As a part of a new project, we have investigated the movable coil electromagnetic drive mechanism (MCEDM) which is new scheme for the reactor control rod adopted by China Advanced Research Reactor (CARR) as shown in Fig.1. To improve a better function of the electromagnetic and magnetic characteristics, new model CRDM, which is named a hybrid bottommounted CRDM (HBCRDM), is proposed. Especially in order to achieve improved thrust force, numerical magnetic field calculations between MCEDM and HBCRDM have been carried out and the HBCRDM FEM results have been compared with the MCEDM FEM results, and FEM results are summarized in the following sections

  18. Modeling and analysis using hybrid Petri nets

    CERN Document Server

    Ghomri, Latéfa

    2007-01-01

    This paper is devoted to the use of hybrid Petri nets (PNs) for modeling and control of hybrid dynamic systems (HDS). Modeling, analysis and control of HDS attract ever more of researchers' attention and several works have been devoted to these topics. We consider in this paper the extensions of the PN formalism (initially conceived for modeling and analysis of discrete event systems) in the direction of hybrid modeling. We present, first, the continuous PN models. These models are obtained from discrete PNs by the fluidification of the markings. They constitute the first steps in the extension of PNs toward hybrid modeling. Then, we present two hybrid PN models, which differ in the class of HDS they can deal with. The first one is used for deterministic HDS modeling, whereas the second one can deal with HDS with nondeterministic behavior. Keywords: Hybrid dynamic systems; D-elementary hybrid Petri nets; Hybrid automata; Controller synthesis

  19. ROCK inhibition prevents early mouse embryo development.

    Science.gov (United States)

    Duan, Xing; Chen, Kun-Lin; Zhang, Yu; Cui, Xiang-Shun; Kim, Nam-Hyung; Sun, Shao-Chen

    2014-08-01

    ROCK is a Rho-GTPase effector that is important for actin assembly and is involved in various cellular functions, including cell contraction, migration, motility, and tumor cell invasion. In this study, we investigated ROCK expression and function during early mouse embryo development. Inhibiting ROCK by Y-27632 treatment at the zygote stage resulted in first cleavage failure, and most embryos failed to develop to the 8-cell stage. When adding Y-27632 at the 8-cell stage, embryos failed to undergo compaction and could not develop into blastocysts. In addition, fluorescence staining intensity analysis indicated that actin expression at blastomere membranes was significantly reduced. After ROCK inhibition, two or more nuclei were observed in a cell, which indicated possible cytokinesis failure. Moreover, after ROCK inhibition with Y-27632, the phosphorylation levels of LIMK1/2, a downstream molecule of ROCK, were decreased at blastomere membranes. Thus, our results showed conserved roles for ROCK in this mammalian embryo model and indicated that a ROCK-LIMK1/2-actin pathway might regulate cleavage and blastocyst formation during early mouse embryo development.

  20. Endoplasmic reticulum stress in periimplantation embryos.

    Science.gov (United States)

    Michalak, Marek; Gye, Myung Chan

    2015-03-01

    Stress coping mechanisms are critical to minimize or overcome damage caused by ever changing environmental conditions. They are designed to promote cell survival. The unfolded protein response (UPR) pathway is mobilized in response to the accumulation of unfolded proteins, ultimately in order to regain endoplasmic reticulum (ER) homeostasis. Various elements of coping responses to ER stress including Perk, Ask1, Bip, Chop, Gadd34, Ire1, Atf4, Atf6, and Xbp1 have been identified and were found to be inducible in oocytes and preimplantation embryos, suggesting that, as a normal part of the cellular adaptive mechanism, these coping responses, including the UPR, play a pivotal role in the development of preimplantation embryos. As such, the UPR-associated molecules and pathways may become useful markers for the potential diagnosis of stress conditions for preimplantation embryos. After implantation, ER stress-induced coping responses become physiologically important for a normal decidual response, placentation, and early organogenesis. Attenuation of ER stress coping responses by tauroursodeoxycholate and salubrinal was effective for prevention of cell death of cultured embryos. Further elucidation of new and relevant ER stress coping responses in periimplantation embryos might contribute to a comprehensive understanding of the regulation of normal development of embryonic development and potentiation of embryonic development in vitro.

  1. In vitro culture of individual mouse preimplantation embryos: the role of embryo density, microwells, oxygen, timing and conditioned media.

    Science.gov (United States)

    Kelley, Rebecca L; Gardner, David K

    2017-02-15

    Single embryo culture is suboptimal compared with group culture, but necessary for embryo monitoring, and culture systems should be improved for single embryos. Pronucleate mouse embryos were used to assess the effect of culture conditions on single embryo development. Single culture either before or after compaction reduced cell numbers (112.2 ± 3.1; 110.2 ± 3.5) compared with group culture throughout (127.0 ± 3.4; P media volume from 20 µl to 2 µl increased blastocyst cell numbers in single embryos cultured in 5% oxygen (84.4 ± 3.2 versus 97.8 ± 2.8; P media to single embryos increased hatching rate and blastocyst cell number (91.5 ± 4.7 versus 113.1 ± 4.4; P media volume and microwells influence single embryo development; and embryo-conditioned media may substitute for group culture.

  2. The presence of a sponsoring embryo in a batch of poor quality thawed embryos significantly increases pregnancy and implantation rate.

    Science.gov (United States)

    Lightman, A; Kol, S; Wayner, V; Vertman, D; Manor, D; Itskovitz-Eldor, J

    1997-04-01

    To evaluate quantitatively the effect of one good-quality (sponsoring) embryo in a batch of low-quality thawed embryos on the implantation and pregnancy rates (PR). Retrospective analysis of data. Tertiary care center IVF clinic affiliated with a university medical school. Between March 1988 and April 1995, 392 IVF patients underwent a total of 440 thawing and ET cycles of 1,436 multicellular embryos. Implantation, clinical pregnancy, and multiple pregnancy rates. In the absence of sponsoring embryos in the thawed batch of embryos, a PR of 9.8% with an implantation rate of 3.1% was achieved. In the presence of a single sponsoring embryo, the PR nearly doubled (18.2%), with a significantly higher implantation rate of 7.0%. Only singleton pregnancies were achieved in the absence of sponsoring embryos compared with 21.7% multiple pregnancies in the single sponsoring embryo group. The presence of a sponsoring embryo in a batch of poor quality thawed embryos is an important factor that significantly increased pregnancy and implantation rates. The optimal strategy for planning batches of multicellular frozen embryos is to include at least one sponsoring embryo in each batch when possible. We speculate that the sponsoring embryo may favorably influence the chances of low-quality embryos to undergo successful implantation.

  3. MORPHOLOGICAL CHANGES DURING THE DEVELOPMENT OF SOMATIC EMBRYOS OF SAGO (Metroxylon sagu Rottb.

    Directory of Open Access Journals (Sweden)

    Pauline D. Kasi

    2016-10-01

    Full Text Available Development of somatic embryos of sago (Metroxylon sagu Rottb. on agar-solidified medium are highly varied producing heterogeneous seedlings. Understanding of this phenomenon may help in improving the cultural procedures and conditions of sagosomatic embryogenesis to obtain uniform seedlings in a large scale. This experiment was conducted at the laboratory for plant cell culture and micropropagation, Indonesian Biotechnology Research Institute for Estate Crops from January to March 2006 to examine morphological changes i.e. color and development stages of sago during their somatic embryo development on an agar-solidified medium. Twenty single globular somatic embryos of sago with specific color (yellowish, greenish, and reddish were cultured in a Petri dish supplemented with a solid medium. The medium was a micronutrients-modified MS (MMS with half strength of macronutrients containing 0.01 mg l-1 ABA, 2 mg l-1 kinetin, 20 g l-1 sucrose, 0.5 g l-1 activated charcoal, and 2 g l-1 gelrite. Parameter observed was the percentage of embryo’s number based on color and developmental stage. The result showed that at the end of 6-week culture passage, most originally greenish (80.8% and reddish (95.8% embryos remained unchanged in their colors, whereas almost half of the originally yellowish embryos turned to greenish and only 30%remained yellowish. At the same time, single globular embryos have changed gradually into the next developmental stages, although not all of the embryos were germinated. The initial color of embryo affected the rate of the developmental stage changes. Yellowish and greenish globular embryos developed more rapidly into cotyledon or germinant stages at 58% and 55% respectively, in 6 weeks than the reddish ones (41%. Therefore, the yellowish and greenish embryos are the best sources of material for in vitro mass propagation and synthetic seed production of sago.

  4. Embryos-the evolutionary boundary of kingdoms of organisms

    Institute of Scientific and Technical Information of China (English)

    FU Da-li

    2005-01-01

    Bioevolution is still a main puzzle and attracts many scientists to research on it. Here I present that organisms have two important properties, definite structure and self-reproduction. Based on the number and connection of the structural units, organisms can be divided into three groups, unicellular, particellular and polycellular organisms. It can be called polycellular evolution that organisms evolve from unicellular, particellular to polycellular. Also it can be called diploid evolution that organisms evolve from haplobes to diplobes, two groups based on the reproductive differences. Some concepts like spore, zygote and embryos are redefined in the paper. Moreover, I present that embryos are the most important boundary of bioevolution and organisms can be divided into two evolutionary phases, the lower and the higher. The lower organisms, Kingdom Microbia (kingd. nov.), are inembryonate, which include Acytophyla (phyl. nov.), bacteria, protozoa, fungi and inembryonate algae. The higher organisms are embryonate and have two branches, Kingdom Plantae and Kingdom Animalia. Plantae are sessile and, autotrophic or sporogenic, which include higher plants and Nudembryophyta (phyl. nov.). Animalia are heterotrophic and, motile or gametogenic, which include all multicellular animals. The new system, which reflects the two important phases of bioevolution and two branches of higher organisms, can really correct the problem of different kingdoms in different researches or by different researchers.

  5. Simple and efficient production of mice derived from embryonic stem cells aggregated with tetraploid embryos.

    Science.gov (United States)

    Li, Xiangyun; Yu, Yuansong; Wei, Wei; Yong, Jun; Yang, Jie; You, Jiefang; Xiong, Xiaoran; Qing, Tingting; Deng, Hongkui

    2005-06-01

    Six newly derived hybrid mouse embryonic stem (ES) cell lines and two inbred ES cell lines were tested for their ability to produce completely ES cell-derived mice by aggregation of ES cells with tetraploid embryos. Forty-five ES cell-tetraploid pups were generated from six hybrid ES cell lines and no pups from two inbred ES cell lines. These pups were found to have increased embryonic and placental weights than control mice. Twenty-two pups survived to adulthood and produced normal offsprings, and the other 23 pups died of several reasons including respiratory distress, abdomen ulcer-like symptoms, and foster failure. The 22 adult ES cell-tetraploid mice were completely ES cell-derived as judged by coat color and germline transmission, only two of them was found to have tetraploid component in liver, blood, and lung as analyzed by microsatellite loci. Our data suggested that genetic heterozygosity is a crucial factor for postnatal survival of ES cell-tetraploid mice, and tetraploid embryo aggregation using hybrid ES cells is a simple and efficient procedure for immediate generation of targeted mouse mutants from genetically modified ES cell clones, in contrast to the standard protocol, which involves the production of chimeras and several breeding steps.

  6. Accuracy of a combined score of zygote and embryo morphology for selecting the best embryos for IVF

    Institute of Scientific and Technical Information of China (English)

    Yu-li QIAN; Ying-hui YE; Chen-ming XU; Fan JIN; He-feng HUANG

    2008-01-01

    Objective:To evaluate the accuracy of a scoring system combining zygote and embryo morphology in predicting the outcome of in vitro fertilization(IVF)treatment.Methods:In a study group,117 consecutive IVF or intracytoplasmic sperm injection(ICSI) cycles with embryo transfer were carried out and 312 embryos were scored Using a combmed scoring system(CSS)of zygote and embryo morphology before transplantation.In a control group,a total of 420 IVF or ICSI cycles were carried out and 1176 embryos were scored using a cumulative embryo score(CES).The effects of the combined scoring system on the embryo implantation rate and pregnancy rate per cycle were analyzed.Results:Using the combined scoring system,the embryo implantation rate(27.6%)and the clinical pregnancy rate(48.7%)were significantly higher than those in the control group(20.8%and 38.6%,respectively).Also,the implantation rate of embryos scoring≥70 (38.5%:82 sacs/213 embryos)was significantly higher (P<0.001)than that of embryos scoring<70(4%:4 sacs/99 embryos).The pregnancy rate of patients with embryos scoring≥70 using the combined scoring system(66.7%)Was significantly higher(P<0.001)than that of patients with embryos scoring≥20 using the cumulative embryo score(59.0%).Conclusion:The results suggest that selecting embryos with a high Score(≥70)using the combined scoring system could inerease the implantation rate and pregnancy rate,and that using a scoring system combining assessments of human zygotes and pre-implantation embryos might predict IVF outcomes more accurately than using a cumulafive embryo score.

  7. Arrested human embryos are more likely to have abnormal chromosomes than developing embryos from women of advanced maternal age.

    Science.gov (United States)

    Qi, Shu-Tao; Liang, Li-Feng; Xian, Ye-Xing; Liu, Jian-Qiao; Wang, Weihua

    2014-01-01

    Aneuploidy is one of the major factors that result in low efficiency in human infertility treatment by in vitro fertilization (IVF). The development of DNA microarray technology allows for aneuploidy screening by analyzing all 23 pairs of chromosomes in human embryos. All chromosome screening for aneuploidy is more accurate than partial chromosome screening, as errors can occur in any chromosome. Currently, chromosome screening for aneuploidy is performed in developing embryos, mainly blastocysts. It has not been performed in arrested embryos and/or compared between developing embryos and arrested embryos from the same IVF cycle. The present study was designed to examine all chromosomes in blastocysts and arrested embryos from the same cycle in patients of advanced maternal ages. Embryos were produced by routine IVF procedures. A total of 90 embryos (45 blastocysts and 45 arrested embryos) from 17 patients were biopsied and analyzed by the Agilent DNA array platform. It was found that 50% of the embryos developed to blastocyst stage; however, only 15.6% of the embryos (both blastocyst and arrested) were euploid, and most (84.4%) of the embryos had chromosomal abnormalities. Further analysis indicated that 28.9% of blastocysts were euploid and 71.1% were aneuploid. By contrast, only one (2.2%) arrested embryo was euploid while others (97.8%) were aneuploid. The prevalence of multiple chromosomal abnormalities in the aneuploid embryos was also higher in the arrested embryos than in the blastocysts. These results indicate that high proportions of human embryos from patients of advanced maternal age are aneuploid, and the arrested embryos are more likely to have abnormal chromosomes than developing embryos.

  8. Efficacy of in vitro embryo transfer in lactating dairy cows using fresh or vitrified embryos produced in a novel embryo culture medium.

    Science.gov (United States)

    Block, J; Bonilla, L; Hansen, P J

    2010-11-01

    Objectives were to determine whether pregnancy success could be improved in lactating cows with timed embryo transfer when embryos were produced in vitro using a medium designed to enhance embryo development and survival after cryopreservation. In experiment 1, embryos (n=569 to 922) were cultured in either modified synthetic oviduct fluid or a serum-free medium, Block-Bonilla-Hansen-7 (BBH7). Development to the blastocyst stage was recorded at d 7, and selected blastocysts (n=79 to 114) were vitrified using open pulled straws. Culture of embryos in BBH7 increased development to the blastocyst stage (41.9±2.0 vs. 14.7±2.0%) and advanced blastocyst stages (expanded, hatching, hatched; 31.1±1.3 vs. 6.4±1.3%) at d 7 and resulted in higher hatching rates at 24h postwarming compared with embryos cultured in modified synthetic oviduct fluid (59.0±0.5 vs. 26.7±0.5%). In experiment 2, embryos were produced using X-sorted semen and cultured in BBH7. At d 7 after insemination, embryos were transferred fresh or following vitrification. Lactating Holstein cows were either subjected to timed artificial insemination (TAI) on the day of presumptive ovulation or used as embryo recipients 7 d later. Embryo recipients received an embryo if a corpus luteum was present. The percentage of cows pregnant at d 32, 46, and 76 of gestation was higher among cows that received fresh embryos compared with TAI cows or cows that received vitrified embryos. At d 76, for example, the proportion and percentage pregnant was 47/150 (31.3%) for cows subjected to TAI, 48/95 (50.5%) for cows receiving fresh embryos, and 39/141 (27.7%) for cows receiving a vitrified embryo. No difference was observed in the percentage of cows pregnant among TAI cows and those that received vitrified embryos. There was a service or transfer number × treatment interaction because differences in pregnancy rate between embryo transfer recipients and cows bred by TAI were greater for cows with more than 3 services or

  9. Human embryos in the original position?

    Science.gov (United States)

    DiSilvestro, Russell

    2005-06-01

    Two different discussions in John Rawls' A Theory of Justice lead naturally to a rather conservative position on the moral status of the human embryo. When discussing paternalism, he claims that the parties in the original position would seek to protect themselves in case they end up as incapacitated or undeveloped human beings when the veil of ignorance is lifted. Since human embryos are examples of such beings, the parties in the original position would seek to protect themselves from their embryonic stages onward. When discussing the basis of equality, Rawls claims that the parties in the original position would guarantee basic rights for all those with the capacity to take part in this original position. To guarantee the basic rights of infants and young children, he goes on to interpret this capacity as a "potentiality that is ordinarily realized in due course." Since human embryos have this potentiality, they too should have basic rights.

  10. Embryos in evolution: evo-devo at the Naples Zoological Station in 1874.

    Science.gov (United States)

    Hall, Brian K

    2009-03-01

    Eighteen seventy-four was a high point in evolutionary embryology. Thanks to Charles Darwin, the theory of evolution by natural selection provided a revolutionary new way of viewing the relationships and origins of organisms on Earth. Thanks to Ernst Haeckel, embryos were the way to study evolution (Haeckel in Generelle morphologie der organismen, vols 1, 2. Verlag Georg Reimer, Berlin, 1866)-it really was embryos in evolution-and recapitulation was in the air. Thanks to Anton Dohrn, a new research facility was on the ground, designed, located and structured to facilitate the study of embryos in evolution. Anton Dohrn devised, designed, financed, supervised the construction and then administered the Naples Zoological Station specifically so that researchers from all nations would have a facility where Darwin's theory of evolution by natural selection could be tested. The zoologists who took advantage of the brand new facility within weeks of its opening late in 1873 established lines of research into evolutionary embryology, the field we now know as evolutionary developmental biology (evo-devo), the study of embryos in evolution. I examine the approach taken by Ambrosius Hubrecht, the first Dutch embryologist to undertake research at the station, and then evaluate the research of three British zoologists-E. Ray Lankester, Albert Dew-Smith, and Francis Maitland (Frank) Balfour. All four sought insights into origins, especially vertebrate origins that rested on comparative embryology, homology, germ layers, and a Darwinian approach to origins.

  11. Folic acid protects against arsenic-mediated embryo toxicity by up-regulating the expression of Dvr1.

    Science.gov (United States)

    Ma, Yan; Zhang, Chen; Gao, Xiao-Bo; Luo, Hai-Yan; Chen, Yang; Li, Hui-hua; Ma, Xu; Lu, Cai-Ling

    2015-11-05

    As a nutritional factor, folic acid can prevent cardiac and neural defects during embryo development. Our previous study showed that arsenic impairs embryo development by down-regulating Dvr1/GDF1 expression in zebrafish. Here, we investigated whether folic acid could protect against arsenic-mediated embryo toxicity. We found that folic acid supplementation increases hatching and survival rates, decreases malformation rate and ameliorates abnormal cardiac and neural development of zebrafish embryos exposed to arsenite. Both real-time PCR analysis and whole in-mount hybridization showed that folic acid significantly rescued the decrease in Dvr1 expression caused by arsenite. Subsequently, our data demonstrated that arsenite significantly decreased cell viability and GDF1 mRNA and protein levels in HEK293ET cells, while folic acid reversed these effects. Folic acid attenuated the increase in subcellular reactive oxygen species (ROS) levels and oxidative adaptor p66Shc protein expression in parallel with the changes in GDF1 expression and cell viability. P66Shc knockdown significantly inhibited the production of ROS and the down-regulation of GDF1 induced by arsenite. Our data demonstrated that folic acid supplementation protected against arsenic-mediated embryo toxicity by up-regulating the expression of Dvr1/GDF1, and folic acid enhanced the expression of GDF1 by decreasing p66Shc expression and subcellular ROS levels.

  12. Laser confers less embryo exposure than acid tyrode for embryo biopsy in preimplantation genetic diagnosis cycles: a randomized study

    Directory of Open Access Journals (Sweden)

    Valle Marcelo

    2011-04-01

    Full Text Available Abstract We compared two methods of zona pellucida drilling. 213 embryos were biopsied with acid Tyrode. Each biopsy took 3 minutes and the entire procedure ~29 minutes. 5% of blastomeres lysed, 49% of embryos became blastocyst and 36% of patients became pregnant. 229 embryos were biopsied with laser. Each biopsy took 30 seconds and the entire procedure ~7 minutes. 2.5% of blastomeres lysed, 50.6% of embryos became blastocyst and 47% of patients became pregnant. We can conclude that laser can be used for embryo biopsy. Reduction of embryo exposure and of removed blastomeres is associated with increased blastocysts available for transfer and a better clinical outcome.

  13. Embryo aggregation does not improve the development of interspecies somatic cell nuclear transfer embryos in the horse.

    Science.gov (United States)

    Gambini, Andrés; De Stéfano, Adrián; Jarazo, Javier; Buemo, Carla; Karlanian, Florencia; Salamone, Daniel Felipe

    2016-09-01

    The low efficiency of interspecies somatic cell nuclear transfer (iSCNT) makes it necessary to investigate new strategies to improve embryonic developmental competence. Embryo aggregation has been successfully applied to improve cloning efficiency in mammals, but it remains unclear whether it could also be beneficial for iSCNT. In this study, we first compared the effect of embryo aggregation over in vitro development and blastocyst quality of porcine, bovine, and feline zona-free (ZF) parthenogenetic (PA) embryos to test the effects of embryo aggregation on species that were later used as enucleated oocytes donors in our iSCNT study. We then assessed whether embryo aggregation could improve the in vitro development of ZF equine iSCNT embryos after reconstruction with porcine, bovine, and feline ooplasm. Bovine- and porcine-aggregated PA blastocysts had significantly larger diameters compared with nonaggregated embryos. On the other hand, feline- and bovine-aggregated PA embryos had higher blastocyst cell number. Embryo aggregation of equine-equine SCNT was found to be beneficial for embryo development as we have previously reported, but the aggregation of three ZF reconstructed embryos did not improve embryo developmental rates on iSCNT. In vitro embryo development of nonaggregated iSCNT was predominantly arrested around the stage when transcriptional activation of the embryonic genome is reported to start on the embryo of the donor species. Nevertheless, independent of embryo aggregation, equine blastocyst-like structures could be obtained in our study using domestic feline-enucleated oocytes. Taken together, these results reported that embryo aggregation enhance in vitro PA embryo development and embryo quality but effects vary depending on the species. Embryo aggregation also improves, as expected, the in vitro embryo development of equine-equine SCNT embryos; however, we did not observe positive effects on equine iSCNT embryo development. Among oocytes

  14. RECYCLING OF CATHETER FOR EMBRYO RECOVERY: A TOOL FOR COSTS REDUCTION IN EQUINE EMBRYO TRANSFER

    Directory of Open Access Journals (Sweden)

    Alberto Lopes Gusmao

    2010-06-01

    Full Text Available The embryo transfer is becoming a widespread practice.Most embryos are collected from spontaneous single ovulatingmares and result in 50% of embryo recovery, increasing the costsof production. To illustrate, the price of a catheter for embryosrecovery range from US$ 194.00 to US$ 250.00 (R$ 350.00 to R$450.00. Therefore, the aim of this work was to verify if catheterwith damaged balloon can be recuperated and reused withoutaltering its efficiency. For this study, two groups were used: acontrol group (GI, n=10, on which the nonsurgical recovery of theembryos of mares was performed with the catheter with originalballoon; and another group (GII, n=20, in which a restored catheterwas utilized. The mares of GI had an embryo recovery rate of60%, and GII mares had an embryo recovery rate of 55%. Therewas not statistical difference between groups I and II (P>0.05.Considering that the material used to restore the catheter costsUS$16.66 (R$30.00, this data show that the recuperation of thecatheters for embryo recovery in mares may reduce costs withoutcompromising the rates of embryo recovery.

  15. Arabidopsis mitochondrial protein slow embryo development1 is essential for embryo development

    Energy Technology Data Exchange (ETDEWEB)

    Ju, Yan; Liu, Chunying; Lu, Wenwen; Zhang, Quan; Sodmergen, E-mail: sodmergn@pku.edu.cn

    2016-05-27

    The plant seeds formation are crucial parts in reproductive process in seed plants as well as food source for humans. Proper embryo development ensure viable seed formation. Here, we showed an Arabidopsis T-DNA insertion mutant slow embryo development1 (sed1) which exhibited retarded embryogenesis, led to aborted seeds. Embryo without SED1 developed slower compared to normal one and could be recognized at early globular stage by its white appearance. In later development stage, storage accumulated poorly with less protein and lipid body production. In vitro culture did not rescue albino embryo. SED1 encoded a protein targeted to mitochondria. Transmission electron microscopic analysis revealed that mitochondria developed abnormally, and more strikingly plastid failed to construct grana in time in sed1/sed1 embryo. These data indicated that SED1 is indispensable for embryogenesis in Arabidopsis, and the mitochondria may be involved in the regulation of many aspects of seed development. -- Highlights: •Arabidopsis SED1 is essential for embryo development. •The sed1 embryo accumulates less storage and has abnormal ultrastructure. •SED1 localizes to the mitochondrion.

  16. Offspring from mouse embryos developed using a simple incubator-free culture system with a deoxidizing agent.

    Science.gov (United States)

    Itoi, Fumiaki; Tokoro, Mikiko; Terashita, Yukari; Yamagata, Kazuo; Fukunaga, Noritaka; Asada, Yoshimasa; Wakayama, Teruhiko

    2012-01-01

    To culture preimplantation embryos in vitro, water-jacketed CO(2) incubators are used widely for maintaining an optimal culture environment in terms of gas phase, temperature and humidity. We investigated the possibility of mouse embryo culture in a plastic bag kept at 37°C. Zygotes derived from in vitro fertilization or collected from naturally mated B6D2F1 female mice were put in a drop of medium on a plastic culture dish and then placed in a commercially available plastic bag. When these were placed in an oven under air at 37°C for 96 h, the rate of blastocyst development and the cell numbers of embryos decreased. However, when the concentration of O(2) was reduced to 5% using a deoxidizing agent and a small oxygen meter, most zygotes developed into blastocysts. These blastocysts were judged normal according to their cell number, Oct3/4 and Cdx2 gene expression levels, the apoptosis rate and the potential for full-term development after embryo transfer to pseudopregnant recipients. Furthermore, using this system, normal offspring were obtained simply by keeping the bag on a warming plate. This culture method was applied successfully to both hybrid and inbred strains. In addition, because the developing embryos could be observed through the transparent wall of the bag, it was possible to capture time-lapse images of live embryos until the blastocyst stage without needing an expensive microscope-based incubation chamber. These results suggest that mouse zygotes are more resilient to their environment than generally believed. This method might prove useful in economical culture systems or for the international shipment of embryos.

  17. Offspring from mouse embryos developed using a simple incubator-free culture system with a deoxidizing agent.

    Directory of Open Access Journals (Sweden)

    Fumiaki Itoi

    Full Text Available To culture preimplantation embryos in vitro, water-jacketed CO(2 incubators are used widely for maintaining an optimal culture environment in terms of gas phase, temperature and humidity. We investigated the possibility of mouse embryo culture in a plastic bag kept at 37°C. Zygotes derived from in vitro fertilization or collected from naturally mated B6D2F1 female mice were put in a drop of medium on a plastic culture dish and then placed in a commercially available plastic bag. When these were placed in an oven under air at 37°C for 96 h, the rate of blastocyst development and the cell numbers of embryos decreased. However, when the concentration of O(2 was reduced to 5% using a deoxidizing agent and a small oxygen meter, most zygotes developed into blastocysts. These blastocysts were judged normal according to their cell number, Oct3/4 and Cdx2 gene expression levels, the apoptosis rate and the potential for full-term development after embryo transfer to pseudopregnant recipients. Furthermore, using this system, normal offspring were obtained simply by keeping the bag on a warming plate. This culture method was applied successfully to both hybrid and inbred strains. In addition, because the developing embryos could be observed through the transparent wall of the bag, it was possible to capture time-lapse images of live embryos until the blastocyst stage without needing an expensive microscope-based incubation chamber. These results suggest that mouse zygotes are more resilient to their environment than generally believed. This method might prove useful in economical culture systems or for the international shipment of embryos.

  18. Differential pattern of Xist RNA accumulation in single blastomeres isolated from 8-cell stage mouse embryos following laser zona drilling.

    Science.gov (United States)

    Hartshorn, Cristina; Rice, John E; Wangh, Lawrence J

    2003-01-01

    Xist gene expression begins at the late 2-cell stage in female mouse embryos and by the third division results in the accumulation of an average 100 copies of Xist RNA per cell, as measured by real-time reverse transcription-polymerase chain reaction (RT-PCR). In the blastocyst, the trophectoderm maintains the paternally imprinted pattern of Xist expression present during early development, while either the maternal or the paternal X chromosome can express Xist among cells of the inner mass. Fluorescent in situ hybridization (FISH) has previously established that Xist transcripts are localized on the silenced X chromosome, forming aggregates of variable dimensions in blastomeres of 8-cell embryos. This observation and the fact that Xist RNA accumulation per cell sharply decreases after morula stage raise the possibility that cells of cleaving embryos contain different levels of Xist RNA, perhaps linked to their subsequent developmental fates. We show here that Xist RNA is efficiently recovered from single blastomeres isolated from 8-cell embryos following laser zona drilling. Sexing of the samples and simultaneous quantification of Xist RNA in individual cells is achieved with a multiplex Xist/Sry real-time RT-PCR assay sensitive to the single-copy level. This analysis reveals that Xist RNA is indeed accumulated to substantially different levels in individual blastomeres of the same 8-cell embryo and that two blastomeres contain most of the molecules per embryo. These results support the conclusion that cells of the early mammalian embryo are not all functionally equivalent. Differential Xist gene expression could arise from differences in DNA methylation, or the order in which cells divide. Copyright 2003 Wiley-Liss, Inc.

  19. Effects of steroidal glycoalkaloids from potatoes (Solanum tuberosum) on in vitro bovine embryo development.

    Science.gov (United States)

    Wang, S; Panter, K E; Gaffield, W; Evans, R C; Bunch, T D

    2005-02-01

    alpha-Solanine and alpha-chaconine are two naturally occurring steroidal glycoalkaloids in potatoes (Solanum tuberosum), and solanidine-N-oxide is a corresponding steroidal aglycone. The objective of this research was to screen potential cyto-toxicity of these potato glycoalkaloids using bovine oocyte maturation, in vitro fertilization techniques and subsequent embryonic development as the in vitro model. A randomized complete block design with four in vitro oocyte maturation (IVM) treatments (Experiment 1) and four in vitro embryo culture (IVC) treatments (Experiment 2) was used. In Experiment 1, bovine oocytes (n=2506) were matured in vitro in medium supplemented with 6 microM of alpha-solanine, alpha-chaconine, solanidine-N-oxide or IVM medium only. The in vitro matured oocytes were then subject to routine IVF and IVC procedures. Results indicated that exposure of bovine oocytes to the steroidal glycoalkaloids during in vitro maturation inhibited subsequent pre-implantation embryo development. Potency of the embryo-toxicity varied between these steroidal glycoalkaloids. In Experiment 2, IVM/IVF derived bovine embryos (n=2370) were cultured in vitro in medium supplemented with 6 microM of alpha-solanine, alpha-chaconine, solanidine-N-oxide or IVC medium only. The results showed that the pre-implantation embryo development is inhibited by exposure to these glycoalkaloids. This effect is significant during the later pre-implantation embryo development period as indicated by fewer numbers of expanded and hatched blastocysts produced in the media containing these alkaloids. Therefore, we conclude that in vitro exposure of oocytes and fertilized ova to the steroidal glycoalkaloids from potatoes inhibits pre-implantation embryo development. Furthermore, we suggest that ingestion of Solanum species containing toxic amounts of glycoalkaloids may have negative effects on pre-implantation embryonic survival.

  20. Transfer of auxinic herbicide resistance from Brassica kaber to Brassica juncea and Brassica rapa through embryo rescue.

    Science.gov (United States)

    Mithila, J; Hall, J Christopher

    2013-01-01

    Auxinic herbicides are widely used in agriculture to selectively control broadleaf weeds. Prolonged use of auxinic herbicides has resulted in the evolution of resistance to these herbicides in some biotypes of Brassica kaber (wild mustard), a common weed in agricultural crops. In this study, auxinic herbicide resistance from B. kaber was transferred to Brassica juncea and Brassica rapa, two commercially important Brassica crops, by traditional breeding coupled with in vitro embryo rescue. A high frequency of embryo regeneration and hybrid plant establishment was achieved. Transfer of auxinic herbicide resistance from B. kaber to the hybrids was assessed by whole-plant screening of hybrids with dicamba, a widely used auxinic herbicide. Furthermore, the hybrids were tested for fertility (both pollen and pistil) and their ability to produce backcross progeny. The auxinic herbicide-resistant trait was introgressed into B. juncea by backcross breeding. DNA ploidy of the hybrids as well as of the backcross progeny was estimated by flow cytometry. Creation of auxinic herbicide-resistant Brassica crops by non-transgenic approaches should facilitate effective weed control, encourage less tillage, provide herbicide rotation options, minimize occurrence of herbicide resistance, and increase acceptance of these crops.