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Sample records for interspecies nuclear transfer

  1. Two-staged nuclear transfer can enhance the developmental ability of goat-sheep interspecies nuclear transfer embryos in vitro.

    PubMed

    Ma, Li-Bing; Cai, Lu; Li, Jia-Jia; Chen, Xiu-Li; Ji, Feng-Yu

    2011-02-01

    The technique of interspecies somatic cell nuclear transfer, in which interspecies cloned embryos can be reconstructed by using domestic animal oocytes as nuclear recipients and endangered animal or human somatic cells as nuclear donors, can afford more opportunities in endangered animal rescue and human tissue transplantation, but the application of this technique is limited by extremely low efficiency which may be attributed to donor nucleus not fully reprogrammed by xenogenic cytoplasm. In this study, goat fetal fibroblasts (GFFs) were used as nuclear donors, in vitro-matured sheep oocytes were used as nuclear recipients, and a two-stage nuclear transfer procedure was performed to improve the developmental ability of goat-sheep interspecies clone embryos. In the first stage nuclear transfer (FSNT), GFFs were injected into the ooplasm of enucleated sheep metaphase-II oocytes, then non-activated reconstructed embryos were cultured in vitro, so that the donor nucleus could be exposed to the ooplasm for a period of time. Subsequently, in the second stage nuclear transfer, FSNT-derived non-activated reconstructed embryo was centrifuged, and the donor nucleus was then transferred into another freshly enucleated sheep oocyte. Compared with the one-stage nuclear transfer, two-stage nuclear transfer could significantly enhance the blastocyst rate of goat-sheep interspecies clone embryos, and this result indicated that longtime exposure to xenogenic ooplasm benefits the donor nucleus to be reprogrammed. The two-stage nuclear transfer procedure has two advantages, one is that the donor nucleus can be exposed to the ooplasm for a long time, the other is that the problem of oocyte aging can be solved. PMID:21082282

  2. Successful cloning of coyotes through interspecies somatic cell nuclear transfer using domestic dog oocytes.

    PubMed

    Hwang, Insung; Jeong, Yeon Woo; Kim, Joung Joo; Lee, Hyo Jeong; Kang, Mina; Park, Kang Bae; Park, Jung Hwan; Kim, Yeun Wook; Kim, Woo Tae; Shin, Taeyoung; Hyun, Sang Hwan; Jeung, Eui-Bae; Hwang, Woo Suk

    2013-01-01

    Interspecies somatic cell nuclear transfer (iSCNT) is an emerging assisted reproductive technology (ART) for preserving Nature's diversity. The scarcity of oocytes from some species makes utilisation of readily available oocytes inevitable. In the present study, we describe the successful cloning of coyotes (Canis latrans) through iSCNT using oocytes from domestic dogs (Canis lupus familiaris or dingo). Transfer of 320 interspecies-reconstructed embryos into 22 domestic dog recipients resulted in six pregnancies, from which eight viable offspring were delivered. Fusion rate and cloning efficiency during iSCNT cloning of coyotes were not significantly different from those observed during intraspecies cloning of domestic dogs. Using neonatal fibroblasts as donor cells significantly improved the cloning efficiency compared with cloning using adult fibroblast donor cells (P<0.05). The use of domestic dog oocytes in the cloning of coyotes in the present study holds promise for cloning other endangered species in the Canidae family using similar techniques. However, there are still limitations of the iSCNT technology, as demonstrated by births of morphologically abnormal coyotes and the clones' inheritance of maternal domestic dog mitochondrial DNA. PMID:23217630

  3. Function of donor cell centrosome in intraspecies and interspecies nuclear transfer embryos

    SciTech Connect

    Zhong Zhisheng; Zhang Gang; Meng Xiaoqian; Zhang Yanling; Chen Dayuan; Schatten, Heide; Sun Qingyuan . E-mail: sunqy1@yahoo.com

    2005-05-15

    Centrosomes, the main microtubule-organizing centers (MTOCs) in most animal cells, are important for many cellular activities such as assembly of the mitotic spindle, establishment of cell polarity, and cell movement. In nuclear transfer (NT), MTOCs that are located at the poles of the meiotic spindle are removed from the recipient oocyte, while the centrosome of the donor cell is introduced. We used mouse MII oocytes as recipients, mouse fibroblasts, rat fibroblasts, or pig granulosa cells as donor cells to construct intraspecies and interspecies nuclear transfer embryos in order to observe centrosome dynamics and functions. Three antibodies against centrin, {gamma}-tubulin, and NuMA, respectively, were used to stain the centrosome. Centrin was not detected either at the poles of transient spindles or at the poles of first mitotic spindles. {gamma}-tubulin translocated into the two poles of the transient spindles, while no accumulated {gamma}-tubulin aggregates were detected in the area adjacent to the two pseudo-pronuclei. At first mitotic metaphase, {gamma}-tubulin was translocated to the spindle poles. The distribution of {gamma}-tubulin was similar in mouse intraspecies and rat-mouse interspecies embryos. The NuMA antibody that we used can recognize porcine but not murine NuMA protein, so it was used to trace the NuMA protein of donor cell in reconstructed embryos. In the pig-mouse interspecies reconstructed embryos, NuMA concentrated between the disarrayed chromosomes soon after activation and translocated to the transient spindle poles. NuMA then immigrated into pseudo-pronuclei. After pseudo-pronuclear envelope breakdown, NuMA was located between the chromosomes and then translocated to the spindle poles of first mitotic metaphase. {gamma}-tubulin antibody microinjection resulted in spindle disorganization and retardation of the first cell division. NuMA antibody microinjection also resulted in spindle disorganization. Our findings indicate that (1) the

  4. Reprogrammed Transcriptome in Rhesus-Bovine Interspecies Somatic Cell Nuclear Transfer Embryos

    PubMed Central

    Wang, Kai; Otu, Hasan H.; Chen, Ying; Lee, Young; Latham, Keith; Cibelli, Jose B.

    2011-01-01

    Background Global activation of the embryonic genome (EGA), one of the most critical steps in early mammalian embryo development, is recognized as the time when interspecies somatic cell nuclear transfer (iSCNT) embryos fail to thrive. Methodology/Principal Findings In this study, we analyzed the EGA-related transcriptome of rhesus-bovine iSCNT 8- to 16-cell embryos and dissected the reprogramming process in terms of embryonic gene activation, somatic gene silencing, and maternal RNA degradation. Compared with fibroblast donor cells, two thousand and seven genes were activated in iSCNT embryos, one quarter of them reaching expression levels comparable to those found in in vitro fertilized (IVF) rhesus embryos. This suggested that EGA in iSCNT embryos had partially recapitulated rhesus embryonic development. Eight hundred and sixty somatic genes were not silenced properly and continued to be expressed in iSCNT embryos, which indicated incomplete nuclear reprogramming. We compared maternal RNA degradation in bovine oocytes between bovine-bovine SCNT and iSCNT embryos. While maternal RNA degradation occurred in both SCNT and iSCNT embryos, we saw more limited overall degradation of maternal RNA in iSCNT embryos than in SCNT embryos. Several important maternal RNAs, like GPF9, were not properly processed in SCNT embryos. Conclusions/Significance Our data suggested that iSCNT embryos are capable of triggering EGA, while a portion of somatic cell-associated genes maintain their expression. Maternal RNA degradation seems to be impaired in iSCNT embryos. Further understanding of the biological roles of these genes, networks, and pathways revealed by iSCNT may expand our knowledge about cell reprogramming, pluripotency, and differentiation. PMID:21799794

  5. Production of rhesus monkey cloned embryos expressing monomeric red fluorescent protein by interspecies somatic cell nuclear transfer

    SciTech Connect

    Zhu, Hai-Ying; Kang, Jin-Dan; Li, Suo; Jin, Jun-Xue; Hong, Yu; Jin, Long; Guo, Qing; Gao, Qing-Shan; Yan, Chang-Guo; Yin, Xi-Jun

    2014-02-21

    Highlights: • Rhesus monkey cells were electroporated with a plasmid containing mRFP1, and an mRFP1-expressing cell line was generated. • For the first time, mRFP1-expressing rhesus monkey cells were used as donor cells for iSCNT. • The effect of VPA on the development of embryos cloned using iSCNT was determined. - Abstract: Interspecies somatic cell nuclear transfer (iSCNT) is a promising method to clone endangered animals from which oocytes are difficult to obtain. Monomeric red fluorescent protein 1 (mRFP1) is an excellent selection marker for transgenically modified cloned embryos during somatic cell nuclear transfer (SCNT). In this study, mRFP-expressing rhesus monkey cells or porcine cells were transferred into enucleated porcine oocytes to generate iSCNT and SCNT embryos, respectively. The development of these embryos was studied in vitro. The percentage of embryos that underwent cleavage did not significantly differ between iSCNT and SCNT embryos (P > 0.05; 71.53% vs. 80.30%). However, significantly fewer iSCNT embryos than SCNT embryos reached the blastocyst stage (2.04% vs. 10.19%, P < 0.05). Valproic acid was used in an attempt to increase the percentage of iSCNT embryos that developed to the blastocyst stage. However, the percentages of embryos that underwent cleavage and reached the blastocyst stage were similar between untreated iSCNT embryos and iSCNT embryos treated with 2 mM valproic acid for 24 h (72.12% vs. 70.83% and 2.67% vs. 2.35%, respectively). These data suggest that porcine-rhesus monkey interspecies embryos can be generated that efficiently express mRFP1. However, a significantly lower proportion of iSCNT embryos than SCNT embryos reach the blastocyst stage. Valproic acid does not increase the percentage of porcine-rhesus monkey iSCNT embryos that reach the blastocyst stage. The mechanisms underling nuclear reprogramming and epigenetic modifications in iSCNT need to be investigated further.

  6. Full-term development of gaur-bovine interspecies somatic cell nuclear transfer embryos: effect of trichostatin A treatment.

    PubMed

    Srirattana, Kanokwan; Imsoonthornruksa, Sumeth; Laowtammathron, Chuti; Sangmalee, Anawat; Tunwattana, Wanchai; Thongprapai, Thamnoon; Chaimongkol, Chockchai; Ketudat-Cairns, Mariena; Parnpai, Rangsun

    2012-06-01

    Trichostatin A (TSA) has previously been used in somatic cell nuclear transfer (SCNT) to improve the cloning efficiency in several species, which led our team to investigate the effects of TSA on the full-term development of bovine SCNT and gaur-bovine interspecies SCNT (gaur iSCNT; gaur somatic cells as donors and bovine oocytes as recipients) embryos. Treatment with 50 nM TSA for 10 h after fusion had no positive effects on the rates of fusion, cleavage, or the development to eight-cell or morula stages in both bovine SCNT and gaur iSCNT embryos. However, TSA treatment significantly enhanced the blastocyst formation rate in bovine SCNT embryos (44 vs. 32-34% in the TSA-treated and TSA-untreated groups, respectively), but had no effects on gaur iSCNT embryos. The fresh blastocysts derived from bovine SCNT and gaur iSCNT embryos (fresh groups), as well as vitrified bovine SCNT blastocysts (vitrified group), were transferred to bovine recipients. We found that TSA treatment increased the pregnancy rates only in recipients receiving fresh bovine SCNT embryos. In recipients receiving TSA-treated bovine SCNT embryos, three cloned calves from the fresh group and twin cloned calves from the vitrified group were delivered; however, no calf was born from the TSA-untreated bovine SCNT embryos. In contrast, one gaur iSCNT calf was born from a recipient receiving blastocysts from the TSA-untreated group. In summary, TSA improved the preimplantation development and pregnancy rates of bovine SCNT embryos, but did not have any beneficial effect on gaur iSCNT embryos. However, one gaur iSCNT calf reached full-term development. PMID:22578161

  7. Absence of nucleolus formation in raccoon dog-porcine interspecies somatic cell nuclear transfer embryos results in embryonic developmental failure

    PubMed Central

    JEON, Yubyeol; NAM, Yeong-Hee; CHEONG, Seung-A; KWAK, Seong-Sung; LEE, Eunsong; HYUN, Sang-Hwan

    2016-01-01

    Interspecies somatic cell nuclear transfer (iSCNT) can be a solution for preservation of endangered species that have limited oocytes. It has been reported that blastocyst production by iSCNT is successful even if the genetic distances between donors and recipients are large. In particular, domestic pig oocytes can support the development of canine to porcine iSCNT embryos. Therefore, we examined whether porcine oocytes may be suitable recipient oocytes for Korean raccoon dog iSCNT. We investigated the effects of trichostatin A (TSA) treatment on iSCNT embryo developmental patterns and nucleolus formation. Enucleated porcine oocytes were fused with raccoon dog fibroblasts by electrofusion and cleavage, and blastocyst development and nucleolus formation were evaluated. To our knowledge, this study is the first in which raccoon dog iSCNT was performed using porcine oocytes; we found that 68.5% of 158 iSCNT embryos had the ability to cleave. However, these iSCNT embryos did not develop past the 4-cell stage. Treatment with TSA did not affect iSCNT embryonic development; moreover, the nuclei failed to form nucleoli at 48 and 72 h post-activation (hpa). In contrast, pig SCNT embryos of the control group showed 18.8% and 87.9% nucleolus formation at 48 and 72 hpa, respectively. Our results demonstrated that porcine cytoplasts efficiently supported the development of raccoon dog iSCNT embryos to the 4-cell stage, the stage of porcine embryonic genome activation (EGA); however, these embryos failed to reach the blastocyst stage and showed defects in nucleolus formation. PMID:27064112

  8. Absence of nucleolus formation in raccoon dog-porcine interspecies somatic cell nuclear transfer embryos results in embryonic developmental failure.

    PubMed

    Jeon, Yubyeol; Nam, Yeong-Hee; Cheong, Seung-A; Kwak, Seong-Sung; Lee, Eunsong; Hyun, Sang-Hwan

    2016-08-25

    Interspecies somatic cell nuclear transfer (iSCNT) can be a solution for preservation of endangered species that have limited oocytes. It has been reported that blastocyst production by iSCNT is successful even if the genetic distances between donors and recipients are large. In particular, domestic pig oocytes can support the development of canine to porcine iSCNT embryos. Therefore, we examined whether porcine oocytes may be suitable recipient oocytes for Korean raccoon dog iSCNT. We investigated the effects of trichostatin A (TSA) treatment on iSCNT embryo developmental patterns and nucleolus formation. Enucleated porcine oocytes were fused with raccoon dog fibroblasts by electrofusion and cleavage, and blastocyst development and nucleolus formation were evaluated. To our knowledge, this study is the first in which raccoon dog iSCNT was performed using porcine oocytes; we found that 68.5% of 158 iSCNT embryos had the ability to cleave. However, these iSCNT embryos did not develop past the 4-cell stage. Treatment with TSA did not affect iSCNT embryonic development; moreover, the nuclei failed to form nucleoli at 48 and 72 h post-activation (hpa). In contrast, pig SCNT embryos of the control group showed 18.8% and 87.9% nucleolus formation at 48 and 72 hpa, respectively. Our results demonstrated that porcine cytoplasts efficiently supported the development of raccoon dog iSCNT embryos to the 4-cell stage, the stage of porcine embryonic genome activation (EGA); however, these embryos failed to reach the blastocyst stage and showed defects in nucleolus formation. PMID:27064112

  9. Interspecies nuclear transfer using fibroblasts from leopard, tiger, and lion ear piece collected postmortem as donor cells and rabbit oocytes as recipients.

    PubMed

    Yelisetti, Uma Mahesh; Komjeti, Suman; Katari, Venu Charan; Sisinthy, Shivaji; Brahmasani, Sambasiva Rao

    2016-06-01

    Skin fibroblast cells were obtained from a small piece of an ear of leopard, lion, and tiger collected postmortem and attempts were made to synchronize the skin fibroblasts at G0/G1 of cell cycle using three different approaches. Efficiency of the approaches was tested following interspecies nuclear transfer with rabbit oocytes as recipient cytoplasm. Fluorescence-activated cell sorting revealed that the proportion of G0/G1 cells increased significantly (P < 0.05) when cells subjected to serum starvation, contact inhibition, and 3 mM sodium butyrate (NaBu) treatment when compared with cycling cells. However, 3 mM NaBu treatment caused alterations in cell morphology and increase in dead cells. Thus, interspecies nuclear transfer was carried out using fibroblast cells subjected to contact inhibition for 72 h, serum starvation for 48 h, and cells treated with 1.0 mM NaBu for 48 h. The fusion rates, the proportion of fused couplets that cleaved to two-cell and developed to blastocyst, were highest in all three species when the donor cells were treated with 1.0 mM NaBu for 48 h. But, the blastocyst percentage of interspecies nuclear embryos (5-6%) was significantly lower when compared with rabbit-rabbit nuclear transfer embryos (22.9%). In conclusion, fibroblast cells of leopard, lion, and tiger were successfully synchronized and used for the development of blastocysts using rabbit oocytes as recipient cytoplasm. PMID:27071624

  10. Embryo aggregation does not improve the development of interspecies somatic cell nuclear transfer embryos in the horse.

    PubMed

    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

  11. Promoting Interspecies Electron Transfer with Biochar

    PubMed Central

    Chen, Shanshan; Rotaru, Amelia-Elena; Shrestha, Pravin Malla; Malvankar, Nikhil S.; Liu, Fanghua; Fan, Wei; Nevin, Kelly P.; Lovley, Derek R.

    2014-01-01

    Biochar, a charcoal-like product of the incomplete combustion of organic materials, is an increasingly popular soil amendment designed to improve soil fertility. We investigated the possibility that biochar could promote direct interspecies electron transfer (DIET) in a manner similar to that previously reported for granular activated carbon (GAC). Although the biochars investigated were 1000 times less conductive than GAC, they stimulated DIET in co-cultures of Geobacter metallireducens with Geobacter sulfurreducens or Methanosarcina barkeri in which ethanol was the electron donor. Cells were attached to the biochar, yet not in close contact, suggesting that electrons were likely conducted through the biochar, rather than biological electrical connections. The finding that biochar can stimulate DIET may be an important consideration when amending soils with biochar and can help explain why biochar may enhance methane production from organic wastes under anaerobic conditions. PMID:24846283

  12. Plugging in or going wireless: strategies for interspecies electron transfer

    PubMed Central

    Shrestha, Pravin Malla; Rotaru, Amelia-Elena

    2014-01-01

    Interspecies exchange of electrons enables a diversity of microbial communities to gain energy from reactions that no one microbe can catalyze. The first recognized strategies for interspecies electron transfer were those that relied on chemical intermediates that are recycled through oxidized and reduced forms. Well-studied examples are interspecies H2 transfer and the cycling of sulfur intermediates in anaerobic photosynthetic communities. Direct interspecies electron transfer (DIET) in which two species establish electrical contact is an alternative. Electrical contacts documented to date include electrically conductive pili, as well as conductive iron minerals and conductive carbon moieties such as activated carbon and biochar. Interspecies electron transfer is central to the functioning of methane-producing microbial communities. The importance of interspecies H2 transfer in many methanogenic communities is clear, but under some circumstances DIET predominates. It is expected that further mechanistic studies and broadening investigations to a wider range of environments will help elucidate the factors that favor specific forms of interspecies electron exchange under different environmental conditions. PMID:24904551

  13. Hardwiring microbes via direct interspecies electron transfer: mechanisms and applications.

    PubMed

    Cheng, Qiwen; Call, Douglas F

    2016-08-10

    Multicellular microbial communities are important catalysts in engineered systems designed to treat wastewater, remediate contaminated sediments, and produce energy from biomass. Understanding the interspecies interactions within them is therefore essential to design effective processes. The flow of electrons within these communities is especially important in the determination of reaction possibilities (thermodynamics) and rates (kinetics). Conventional models of electron transfer incorporate the diffusion of metabolites generated by one organism and consumed by a second, frequently referred to as mediated interspecies electron transfer (MIET). Evidence has emerged in the last decade that another method, called direct interspecies electron transfer (DIET), may occur between organisms or in conjunction with electrically conductive materials. Recent research has suggested that DIET can be stimulated in engineered systems to improve desired treatment goals and energy recovery in systems such as anaerobic digesters and microbial electrochemical technologies. In this review, we summarize the latest understanding of DIET mechanisms, the associated microorganisms, and the underlying thermodynamics. We also critically examine approaches to stimulate DIET in engineered systems and assess their effectiveness. We find that in most cases attempts to promote DIET in mixed culture systems do not yield the improvements expected based on defined culture studies. Uncertainties of other processes that may be co-occurring in real systems, such as contaminant sorption and biofilm promotion, need to be further investigated. We conclude by identifying areas of future research related to DIET and its application in biological treatment processes. PMID:27349520

  14. Syntrophic growth via quinone-mediated interspecies electron transfer

    PubMed Central

    Smith, Jessica A.; Nevin, Kelly P.; Lovley, Derek R.

    2015-01-01

    The mechanisms by which microbial species exchange electrons are of interest because interspecies electron transfer can expand the metabolic capabilities of microbial communities. Previous studies with the humic substance analog anthraquinone-2,6-disulfonate (AQDS) suggested that quinone-mediated interspecies electron transfer (QUIET) is feasible, but it was not determined if sufficient energy is available from QUIET to support the growth of both species. Furthermore, there have been no previous studies on the mechanisms for the oxidation of anthrahydroquinone-2,6-disulfonate (AHQDS). A co-culture of Geobacter metallireducens and G. sulfurreducens metabolized ethanol with the reduction of fumarate much faster in the presence of AQDS, and there was an increase in cell protein. G. sulfurreducens was more abundant, consistent with G. sulfurreducens obtaining electrons from acetate that G. metallireducens produced from ethanol, as well as from AHQDS. Co-cultures initiated with a citrate synthase-deficient strain of G. sulfurreducens that was unable to use acetate as an electron donor also metabolized ethanol with the reduction of fumarate and cell growth, but acetate accumulated over time. G. sulfurreducens and G. metallireducens were equally abundant in these co-cultures reflecting the inability of the citrate synthase-deficient strain of G. sulfurreducens to metabolize acetate. Evaluation of the mechanisms by which G. sulfurreducens accepts electrons from AHQDS demonstrated that a strain deficient in outer-surface c-type cytochromes that are required for AQDS reduction was as effective at QUIET as the wild-type strain. Deletion of additional genes previously implicated in extracellular electron transfer also had no impact on QUIET. These results demonstrate that QUIET can yield sufficient energy to support the growth of both syntrophic partners, but that the mechanisms by which electrons are derived from extracellular hydroquinones require further investigation. PMID

  15. Incompatibility between Nuclear and Mitochondrial Genomes Contributes to an Interspecies Reproductive Barrier.

    PubMed

    Ma, Hong; Marti Gutierrez, Nuria; Morey, Robert; Van Dyken, Crystal; Kang, Eunju; Hayama, Tomonari; Lee, Yeonmi; Li, Ying; Tippner-Hedges, Rebecca; Wolf, Don P; Laurent, Louise C; Mitalipov, Shoukhrat

    2016-08-01

    Vertebrate cells carry two different genomes, nuclear (nDNA) and mitochondrial (mtDNA), both encoding proteins involved in oxidative phosphorylation. Because of the extensive interactions, adaptive coevolution of the two genomes must occur to ensure normal mitochondrial function. To investigate whether incompatibilities between these two genomes could contribute to interspecies reproductive barriers, we performed reciprocal mtDNA replacement (MR) in zygotes between widely divergent Mus m. domesticus (B6) and conplastic Mus m. musculus (PWD) mice. Transfer of MR1 cybrid embryos (B6nDNA-PWDmtDNA) supported normal development of F1 offspring with reduced male fertility but unaffected reproductive fitness in females. Furthermore, donor PWD mtDNA was faithfully transmitted through the germline into F2 and F3 generations. In contrast, reciprocal MR2 (PWDnDNA-B6mtDNA) produced high embryonic loss and stillborn rates, suggesting an association between mitochondrial function and infertility. These results strongly suggest that functional incompatibility between nuclear and mitochondrial genomes contributes to interspecies reproductive isolation in mammals. PMID:27425585

  16. Natural interspecies transfer of mitochondrial DNA in amphibians.

    PubMed Central

    Spolsky, C; Uzzell, T

    1984-01-01

    mtDNAs of two Central European water frog species, Rana ridibunda and Rana lessonae, were examined by electrophoresis of restriction enzyme fragments. Two types of mtDNA occur in R. ridibunda. One shares with mtDNA of R. lessonae 25.8% of 132 fragments generated by 19 enzymes, corresponding to a nucleotide sequence divergence of 8.1%; the other has diverged from R. lessonae mtDNA by only 0.3%. This latter type is a variant R. lessonae mtDNA that has been transferred into R. ridibunda; the introgression may have occurred via the hybridogenetic hybrid lineages collectively known as Rana esculenta. Of 37 R. ridibunda from Poland, 59% had the typical R. ridibunda mtDNA; 41% had the modified R. lessonae mtDNA as did a single individual from Switzerland (introduced). A single R. ridibunda from Turkey, outside the present range of R. lessonae, had the typical R. ridibunda mtDNA phenotype. Discordancies between inheritance of mitochondrial and nuclear genomes point up the danger of relying on a single molecular feature in reconstructing phylogeny. In addition, studies of mtDNA provide otherwise inaccessible information on complex evolutionary histories of closely related species. A knowledge of these complexities is important to an understanding of phylogenetic relationships and of the genetic processes that underlie the evolution of clonal taxa. Images PMID:6091109

  17. Collisionless inter-species energy transfer and turbulent heating in drift wave turbulence

    SciTech Connect

    Zhao, L.; Diamond, P. H.

    2012-08-15

    We reconsider the classic problems of calculating 'turbulent heating' and collisionless inter-species transfer of energy in drift wave turbulence. These issues are of interest for low collisionality, electron heated plasmas, such as ITER, where collisionless energy transfer from electrons to ions is likely to be significant. From the wave Poynting theorem at steady state, a volume integral over an annulus r{sub 1}=-S{sub r}|{sub r{sub 1}{sup r{sub 2}}}{ne}0. Here S{sub r} is the wave energy density flux in the radial direction. Thus, a wave energy flux differential across an annular region indeed gives rise to a net heating, in contrast to previous predictions. This heating is related to the Reynolds work by the zonal flow, since S{sub r} is directly linked to the zonal flow drive. In addition to net heating, there is inter-species heat transfer. For collisionless electron drift waves, the total turbulent energy source for collisionless heat transfer is due to quasilinear electron cooling. Subsequent quasilinear ion heating occurs through linear ion Landau damping. In addition, perpendicular heating via ion polarization currents contributes to ion heating. Since at steady state, Reynolds work of the turbulence on the zonal flow must balance zonal flow frictional damping ({approx}{nu}{sub ii}{sup 2}{approx}|(e{phi}(tilde sign)/T)|{sup 4}), it is no surprise that zonal flow friction appears as an important channel for ion heating. This process of energy transfer via zonal flow has not previously been accounted for in analyses of energy transfer. As an application, we compare the rate of turbulent energy transfer in a low collisionality plasma with the rate of the energy transfer by collisions. The result shows that the collisionless turbulent energy transfer is a significant energy coupling process for ITER plasma.

  18. Interspecies distances between propionic acid degraders and methanogens in syntrophic consortia for optimal hydrogen transfer.

    PubMed

    Felchner-Zwirello, Monika; Winter, Josef; Gallert, Claudia

    2013-10-01

    A mixed culture from an anaerobic biowaste digester was enriched on propionate and used to investigate interspecies hydrogen transfer in dependence of spatial distances between propionate degraders and methanogens. From 20.3 mM propionate, 20.8 mM acetate and 15.5 mM methane were formed. Maximum specific propionate oxidation and methane formation rates were 49 and 23 mmol mg(-1) day(-1), respectively. Propionate oxidation was inhibited by only 20 mM acetate by about 50 %. Intermediate formate formation during inhibited methanogensis was observed. The spatial distribution and the biovolume fraction of propionate degraders and of methanogens in relation to the total population during aggregate formation were determined. Measurements of interbacterial distances were conducted with fluorescence in situ hybridization by application of group-specific 16S rRNA-targeted probes and 3D image analyses. With increasing incubation time, floc formation and growth up to 54 μm were observed. Propionate degraders and methanogens were distributed randomly in the flocs. The methanogenic biovolume fraction was high at the beginning and remained constant over 42 days, whereas the fraction of propionate degraders increased with time during propionate feeding. Interbacterial distances between propionate degraders and methanogens decreased with time from 5.30 to 0.29 μm, causing an increase of the maximum possible hydrogen flux from 1.1 to 10.3 nmol ml(-1) min(-1). The maximum possible hydrogen flux was always higher than the hydrogen formation and consumption rate, indicating that reducing the interspecies distance by aggregation is advantageous in complex ecosystems. PMID:23233207

  19. Direct interspecies electron transfer accelerates syntrophic oxidation of butyrate in paddy soil enrichments.

    PubMed

    Li, Huijuan; Chang, Jiali; Liu, Pengfei; Fu, Li; Ding, Dewen; Lu, Yahai

    2015-05-01

    Syntrophic interaction occurs during anaerobic fermentation of organic substances forming methane as the final product. H2 and formate are known to serve as the electron carriers in this process. Recently, it has been shown that direct interspecies electron transfer (DIET) occurs for syntrophic CH4 production from ethanol and acetate. Here, we constructed paddy soil enrichments to determine the involvement of DIET in syntrophic butyrate oxidation and CH4 production. The results showed that CH4 production was significantly accelerated in the presence of nanoFe3 O4 in all continuous transfers. This acceleration increased with the increase of nanoFe3 O4 concentration but was dismissed when Fe3 O4 was coated with silica that insulated the mineral from electrical conduction. NanoFe3 O4 particles were found closely attached to the cell surfaces of different morphology, thus bridging cell connections. Molecular approaches, including DNA-based stable isotope probing, revealed that the bacterial Syntrophomonadaceae and Geobacteraceae, and the archaeal Methanosarcinaceae, Methanocellales and Methanobacteriales, were involved in the syntrophic butyrate oxidation and CH4 production. Among them, the growth of Geobacteraceae strictly relied on the presence of nanoFe3 O4 and its electrical conductivity in particular. Other organisms, except Methanobacteriales, were present in enrichments regardless of nanoFe3 O4 amendment. Collectively, our study demonstrated that the nanoFe3 O4 -facilitated DIET occurred in syntrophic CH4 production from butyrate, and Geobacter species played the key role in this process in the paddy soil enrichments. PMID:25059331

  20. Unexpected Specificity of Interspecies Cobamide Transfer from Geobacter spp. to Organohalide-Respiring Dehalococcoides mccartyi Strains

    PubMed Central

    Yan, Jun; Ritalahti, Kirsti M.; Wagner, Darlene D.

    2012-01-01

    Dehalococcoides mccartyi strains conserve energy from reductive dechlorination reactions catalyzed by corrinoid-dependent reductive dehalogenase enzyme systems. Dehalococcoides lacks the ability for de novo corrinoid synthesis, and pure cultures require the addition of cyanocobalamin (vitamin B12) for growth. In contrast, Geobacter lovleyi, which dechlorinates tetrachloroethene to cis-1,2-dichloroethene (cis-DCE), and the nondechlorinating species Geobacter sulfurreducens have complete sets of cobamide biosynthesis genes and produced 12.9 ± 2.4 and 24.2 ± 5.8 ng of extracellular cobamide per liter of culture suspension, respectively, during growth with acetate and fumarate in a completely synthetic medium. G. lovleyi-D. mccartyi strain BAV1 or strain FL2 cocultures provided evidence for interspecies corrinoid transfer, and cis-DCE was dechlorinated to vinyl chloride and ethene concomitant with Dehalococcoides growth. In contrast, negligible increase in Dehalococcoides 16S rRNA gene copies and insignificant dechlorination occurred in G. sulfurreducens-D. mccartyi strain BAV1 or strain FL2 cocultures. Apparently, G. lovleyi produces a cobamide that complements Dehalococcoides' nutritional requirements, whereas G. sulfurreducens does not. Interestingly, Dehalococcoides dechlorination activity and growth could be restored in G. sulfurreducens-Dehalococcoides cocultures by adding 10 μM 5′,6′-dimethylbenzimidazole. Observations made with the G. sulfurreducens-Dehalococcoides cocultures suggest that the exchange of the lower ligand generated a cobalamin, which supported Dehalococcoides activity. These findings have implications for in situ bioremediation and suggest that the corrinoid metabolism of Dehalococcoides must be understood to faithfully predict, and possibly enhance, reductive dechlorination activities. PMID:22773645

  1. Potential for direct interspecies electron transfer in an electric-anaerobic system to increase methane production from sludge digestion

    PubMed Central

    Zhao, Zhiqiang; Zhang, Yaobin; Wang, Liying; Quan, Xie

    2015-01-01

    Direct interspecies electron transfer (DIET) between Geobacter species and Methanosaeta species is an alternative to interspecies hydrogen transfer (IHT) in anaerobic digester, which however has not been established in anaerobic sludge digestion as well as in bioelectrochemical systems yet. In this study, it was found that over 50% of methane production of an electric-anaerobic sludge digester was resulted from unknown pathway. Pyrosequencing analysis revealed that Geobacter species were significantly enriched with electrodes. Fluorescence in situ hybridization (FISH) further confirmed that the dominant Geobacter species enriched belonged to Geobacter metallireducens. Together with Methanosaeta species prevailing in the microbial communities, the direct electron exchange between Geobacter species and Methanosaeta species might be an important reason for the “unknown” increase of methane production. Conductivity of the sludge in this electric-anaerobic digester was about 30% higher than that of the sludge in a control digester without electrodes. This study not only revealed for the first time that DIET might be the important mechanism on the methanogenesis of bioelectrochemical system, but also provided a new method to enhance DIET by means of bioelectric enrichment of Geobacter species. PMID:26057581

  2. Communities stimulated with ethanol to perform direct interspecies electron transfer for syntrophic metabolism of propionate and butyrate.

    PubMed

    Zhao, Zhiqiang; Zhang, Yaobin; Yu, Qilin; Dang, Yan; Li, Yang; Quan, Xie

    2016-10-01

    Direct interspecies electron transfer (DIET) has been considered as an alternative to interspecies H2 transfer (IHT) for syntrophic metabolism, but the microorganisms capable of metabolizing the key intermediates, such as propionate and butyrate, via DIET have yet to be described. A strategy of culturing the enrichments with ethanol as a DIET substrate to stimulate the communities for the syntrophic metabolism of propionate and/or butyrate was proposed in this study. The results showed that the syntrophic propionate and/or butyrate degradation was significantly improved in the ethanol-stimulated reactor when propionate/butyrate was the sole carbon source. The conductivity of the ethanol-stimulated enrichments was as 5 folds (for propionate)/76 folds (for butyrate) as that of the traditional enrichments (never ethanol fed). Microbial community analysis revealed that Geobacter species known to proceed DIET were only detected in the ethanol-stimulated enrichments. Together with the significant increase of Methanosaeta and Methanosarcina species in these enrichments, the potential DIET between Geobacter and Methanosaeta or Methanosarcina species might be established to improve the syntrophic propionate and/or butyrate degradation. Further experiments demonstrated that granular activated carbon (GAC) could improve the syntrophic metabolism of propionate and/or butyrate of the ethanol-stimulated enrichments, while almost no effects on the traditional enrichments. Also, the high H2 partial pressure could inhibit the syntrophic propionate and/or butyrate degradation of the traditional enrichments, but its effect on that of the ethanol-stimulated enrichments was negligible. PMID:27403870

  3. Expanding the Diet for DIET: Electron Donors Supporting Direct Interspecies Electron Transfer (DIET) in Defined Co-Cultures

    PubMed Central

    Wang, Li-Ying; Nevin, Kelly P.; Woodard, Trevor L.; Mu, Bo-Zhong; Lovley, Derek R.

    2016-01-01

    Direct interspecies electron transfer (DIET) has been recognized as an alternative to interspecies H2 transfer as a mechanism for syntrophic growth, but previous studies on DIET with defined co-cultures have only documented DIET with ethanol as the electron donor in the absence of conductive materials. Co-cultures of Geobacter metallireducens and Geobacter sulfurreducens metabolized propanol, butanol, propionate, and butyrate with the reduction of fumarate to succinate. G. metallireducens utilized each of these substrates whereas only electrons available from DIET supported G. sulfurreducens respiration. A co-culture of G. metallireducens and a strain of G. sulfurreducens that could not metabolize acetate oxidized acetate with fumarate as the electron acceptor, demonstrating that acetate can also be syntrophically metabolized via DIET. A co-culture of G. metallireducens and Methanosaeta harundinacea previously shown to syntrophically convert ethanol to methane via DIET metabolized propanol or butanol as the sole electron donor, but not propionate or butyrate. The stoichiometric accumulation of propionate or butyrate in the propanol- or butanol-fed cultures demonstrated that M. harundinaceae could conserve energy to support growth solely from electrons derived from DIET. Co-cultures of G. metallireducens and Methanosarcina barkeri could also incompletely metabolize propanol and butanol and did not metabolize propionate or butyrate as sole electron donors. These results expand the range of substrates that are known to be syntrophically metabolized through DIET, but suggest that claims of propionate and butyrate metabolism via DIET in mixed microbial communities warrant further validation. PMID:26973614

  4. N. elongata produces type IV pili that mediate interspecies gene transfer with N. gonorrhoeae.

    PubMed

    Higashi, Dustin L; Biais, Nicolas; Weyand, Nathan J; Agellon, Al; Sisko, Jennifer L; Brown, Lewis M; So, Magdalene

    2011-01-01

    The genus Neisseria contains at least eight commensal and two pathogenic species. According to the Neisseria phylogenetic tree, commensals are basal to the pathogens. N. elongata, which is at the opposite end of the tree from N. gonorrhoeae, has been observed to be fimbriated, and these fimbriae are correlated with genetic competence in this organism. We tested the hypothesis that the fimbriae of N. elongata are Type IV pili (Tfp), and that Tfp functions in genetic competence. We provide evidence that the N. elongata fimbriae are indeed Tfp. Tfp, as well as the DNA Uptake Sequence (DUS), greatly enhance N. elongata DNA transformation. Tfp allows N. elongata to make intimate contact with N. gonorrhoeae and to mediate the transfer of antibiotic resistance markers between these two species. We conclude that Tfp functional for genetic competence is a trait of a commensal member of the Neisseria genus. Our findings provide a mechanism for the horizontal gene transfer that has been observed among Neisseria species. PMID:21731720

  5. Development of a pheasant interspecies primordial germ cell transfer to chicken embryo: effect of donor cell sex on chimeric semen production.

    PubMed

    Kang, S J; Choi, J W; Park, K J; Lee, Y M; Kim, T M; Sohn, S H; Lim, J M; Han, J Y

    2009-09-01

    This study was conducted to evaluate whether the sex of donor primordial germ cells (PGCs) influences production of chimeric semen from recipient hatchlings produced by interspecies transfer between pheasant (Phasianus colchicus) and chicken (Gallus gallus). Pheasant PGCs were retrieved from 7-d-old embryos and subsequently transferred into circulatory blood of 2.5-d-old (Stage 17) embryos. The sex of embryos was discerned 3 to 6 days after laying, and in preliminary study, overall rate of embryo survival after sexing was 74.6% with male-to-female ratio of 0.49 to 0.51. In Experiment 1, magnetic-activated cell sorting (MACS) using QCR1 antibody was effective for enriching the population of male and female PGCs in gonadal cells (9.2- to 12.5-fold and 10.8- to 19.5-fold increase, respectively). In Experiment 2, an increase in the number of hatchlings producing chimeric semen was detected after the homosexual transfer of male-to-male compared with that after the heterosexual transfer of female-to-male (68% to 88%). Significant increase was found in the frequency of chimeric semen production (0.96 to 1.68 times); production of pheasant progenies by artificial insemination using chimeric semen was also increased in the homosexual transfer (0 to 3 cases). In conclusion, the homosexual PGC transfer of male-to-male yielded better rate of generating pheasant progenies after test cross-reproduction than that of the heterosexual transfer of female-to-male, which could improve the efficiency of interspecies germ cell transfer system. PMID:19515408

  6. Nuclear propulsion for orbital transfer

    SciTech Connect

    Beale, G.A.; Lawrence, T.J. )

    1989-06-01

    The state of the art in nuclear propulsion for orbital transfer is discussed. Cryogenic propulsion, electric propulsion, solar-thermal propulsion and direct nuclear propulsion are examined in this context. New technologies with exceptional promise are addressed, emphasizing the particle test bed nuclear engine.

  7. Transfer reactions in nuclear astrophysics

    NASA Astrophysics Data System (ADS)

    Bardayan, D. W.

    2016-08-01

    To a high degree many aspects of the large-scale behavior of objects in the Universe are governed by the underlying nuclear physics. In fact the shell structure of nuclear physics is directly imprinted into the chemical abundances of the elements. The tranquility of the night sky is a direct result of the relatively slow rate of nuclear reactions that control and determines a star’s fate. Understanding the nuclear structure and reaction rates between nuclei is vital to understanding our Universe. Nuclear-transfer reactions make accessible a wealth of knowledge from which we can extract much of the required nuclear physics information. A review of transfer reactions for nuclear astrophysics is presented with an emphasis on the experimental challenges and opportunities for future development.

  8. Potential enhancement of direct interspecies electron transfer for syntrophic metabolism of propionate and butyrate with biochar in up-flow anaerobic sludge blanket reactors.

    PubMed

    Zhao, Zhiqiang; Zhang, Yaobin; Holmes, Dawn E; Dang, Yan; Woodard, Trevor L; Nevin, Kelly P; Lovley, Derek R

    2016-06-01

    Promoting direct interspecies electron transfer (DIET) to enhance syntrophic metabolism may be a strategy for accelerating the conversion of organic wastes to methane, but microorganisms capable of metabolizing propionate and butyrate via DIET under methanogenic conditions have yet to be identified. In an attempt to establish methanogenic communities metabolizing propionate or butyrate with DIET, enrichments were initiated with up-flow anaerobic sludge blanket (UASB), similar to those that were previously reported to support communities that metabolized ethanol with DIET that relied on direct biological electrical connections. In the absence of any amendments, microbial communities enriched were dominated by microorganisms closely related to pure cultures that are known to metabolize propionate or butyrate to acetate with production of H2. When biochar was added to the reactors there was a substantial enrichment on the biochar surface of 16S rRNA gene sequences closely related to Geobacter and Methanosaeta species known to participate in DIET. PMID:26967338

  9. Nuclear technology transfer to China

    SciTech Connect

    Crane, A.T.

    1987-01-01

    China has severe power shortages and considerable nuclear expertise available from its military programs. These factors led to great expectations of how fast its nuclear power program might expand. The U.S. recently implemented a controversial nuclear cooperation agreement with China, permitting U.S. companies to compete if this market reopens. The major concern over the agreement was that in the past China apparently showed an alarming disregard for the dangers of nuclear proliferation. It is unlikely that China would use nuclear power equipment to further its nuclear weapons program, but the effectiveness of the U.S. nonproliferation stance has been in part dependent on other countries viewing our position as uncompromising. The vagueness of certain provisions in the agreement with China may have weakened this stance. Another concern is that access to U.S. pressurized water reactor technology could improve their submarine reactors, which could be detrimental to U.S. security interests if relations with China deteriorate. However, it appears that the only significant advantage that would accrue would be a general upgrading of management practices and quality control, which would be available from any other nuclear supplier. If the opportunity for the sale of nuclear equipment to China emerges, the nuclear technology transfer that would be involved, if carefully managed, should contribute to the national interest.

  10. Bovine somatic cell nuclear transfer.

    PubMed

    Ross, Pablo J; Cibelli, Jose B

    2010-01-01

    Somatic cell nuclear transfer (SCNT) is a technique by which the nucleus of a differentiated cell is introduced into an oocyte from which its genetic material has been removed by a process called enucleation. In mammals, the reconstructed embryo is artificially induced to initiate embryonic development (activation). The oocyte turns the somatic cell nucleus into an embryonic nucleus. This process is called nuclear reprogramming and involves an important change of cell fate, by which the somatic cell nucleus becomes capable of generating all the cell types required for the formation of a new individual, including extraembryonic tissues. Therefore, after transfer of a cloned embryo to a surrogate mother, an offspring genetically identical to the animal from which the somatic cells where isolated, is born. Cloning by nuclear transfer has potential applications in agriculture and biomedicine, but is limited by low efficiency. Cattle were the second mammalian species to be cloned after Dolly the sheep, and it is probably the most widely used species for SCNT experiments. This is, in part due to the high availability of bovine oocytes and the relatively higher efficiency levels usually obtained in cattle. Given the wide utilization of this species for cloning, several alternatives to this basic protocol can be found in the literature. Here we describe a basic protocol for bovine SCNT currently being used in our laboratory, which is amenable for the use of the nuclear transplantation technique for research or commercial purposes. PMID:20336522

  11. Cytoplasmic Determination of Meiotic Spindle Size Revealed by a Unique Inter-Species Germinal Vesicle Transfer Model

    PubMed Central

    Wang, Zhong-Wei; Zhang, Guang-Li; Schatten, Heide; Carroll, John; Sun, Qing-Yuan

    2016-01-01

    Spindle sizes are different in diverse species and cell types. In frogs, the meiotic spindle size is positively correlated with the egg cell volume. Across species, relatively small mouse oocytes (70–80 μm) have a relatively large spindle while larger pig oocytes (about 120 μm) have a considerably smaller spindle. In this study we investigated whether species-specific oocyte spindle size was determined by cytoplasmic or nuclear factors. By exchanging the germinal vesicle between mouse and pig oocytes, we obtained two kinds of reconstructed oocytes: one with mouse ooplasm and pig GV (mCy-pGV oocyte), and the other with pig ooplasm and mouse GV (pCy-mGV oocyte). We show that the MII spindle size of the mCy-pGV oocyte is similar to that of the mouse meiotic spindle and significantly larger than that of the pig meiotic spindle. The timing of oocyte maturation also followed that of the species from which the oocyte cytoplasm arose, although some impact of the origin of the GV was observed. These data suggest that spindle size and the timing of meiotic progression are governed by cytoplasmic components rather than cytoplasmic volume and GV materials. PMID:26813698

  12. Somatic cell nuclear transfer in zebrafish.

    PubMed

    Siripattarapravat, Kannika; Pinmee, Boonya; Venta, Patrick J; Chang, Chia-Cheng; Cibelli, Jose B

    2009-10-01

    We developed a method for somatic cell nuclear transfer in zebrafish using laser-ablated metaphase II eggs as recipients, the micropyle for transfer of the nucleus and an egg activation protocol after nuclear reconstruction. We produced clones from cells of both embryonic and adult origins, although the latter did not give rise to live adult clones. PMID:19718031

  13. Reproduction of wild birds via interspecies germ cell transplantation.

    PubMed

    Kang, Seok Jin; Choi, Jin Won; Kim, Sun Young; Park, Kyung Je; Kim, Tae Min; Lee, Young Mok; Kim, Heebal; Lim, Jeong Mook; Han, Jae Yong

    2008-11-01

    The present study was conducted to apply an interspecies germ cell transfer technique to wild bird reproduction. Pheasant (Phasianus colchicus) primordial germ cells (PGCs) retrieved from the gonads of 7-day-old embryos were transferred to the bloodstream of 2.5-day-old chicken (Gallus gallus) embryos. Pheasant-to-chicken germline chimeras hatched from the recipient embryos, and 10 pheasants were derived from testcross reproduction of the male chimeras with female pheasants. Gonadal migration of the transferred PGCs, their involvement in spermatogenesis, and production of chimeric semen were confirmed. The phenotype of pheasant progenies derived from the interspecies transfer was identical to that of wild pheasants. The average efficiency of reproduction estimated from the percentage of pheasants to total progenies was 17.5%. In conclusion, interspecies germ cell transfer into a developing embryo can be used for wild bird reproduction, and this reproductive technology may be applicable in conserving endangered bird species. PMID:18685127

  14. Dry Transfer Systems for Used Nuclear Fuel

    SciTech Connect

    Brett W. Carlsen; Michaele BradyRaap

    2012-05-01

    The potential need for a dry transfer system (DTS) to enable retrieval of used nuclear fuel (UNF) for inspection or repackaging will increase as the duration and quantity of fuel in dry storage increases. This report explores the uses for a DTS, identifies associated general functional requirements, and reviews existing and proposed systems that currently perform dry fuel transfers. The focus of this paper is on the need for a DTS to enable transfer of bare fuel assemblies. Dry transfer systems for UNF canisters are currently available and in use for transferring loaded canisters between the drying station and storage and transportation casks.

  15. Heat transfer in a nuclear rocket engine

    SciTech Connect

    Konyukhov, G.V.; Petrov, A.I.

    1995-02-01

    Special features of heat transfer in the reactor of a nuclear rocket engine (NRE) are dealt with. It is shown that the design of the cooling system of the NRE reactor is governed by its stability to small deviations of the parameters from the corresponding calculated values and the possibility of compensating for effects due to nonuniformities and distrubances of various types and scales.

  16. 10 CFR 70.42 - Transfer of special nuclear material.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Transfer of special nuclear material. 70.42 Section 70.42 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL Acquisition, Use and Transfer of Special Nuclear Material, Creditors' Rights § 70.42 Transfer of...

  17. 10 CFR 70.42 - Transfer of special nuclear material.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Transfer of special nuclear material. 70.42 Section 70.42 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL Acquisition, Use and Transfer of Special Nuclear Material, Creditors' Rights § 70.42 Transfer of...

  18. Nuclear transfer and transgenesis in the pig.

    PubMed

    Kurome, Mayuko; Kessler, Barbara; Wuensch, Annegret; Nagashima, Hiroshi; Wolf, Eckhard

    2015-01-01

    Somatic cell nuclear transfer (SCNT) using genetically modified donor cells facilitates the generation of tailored pig models for biomedical research and for xenotransplantation. Up to now, SCNT is the main way to generate gene-targeted pigs, since germ line-competent pluripotent stem cells are not available for this species. In this chapter, we introduce our routine workflow for the production of genetically engineered pigs, especially focused on the genetic modification of somatic donor cells, SCNT using in vitro matured oocytes, and laparoscopic embryo transfer. PMID:25287337

  19. Bovine ooplasm partially remodels primate somatic nuclei following somatic cell nuclear transfer.

    PubMed

    Wang, Kai; Beyhan, Zeki; Rodriguez, Ramon M; Ross, Pablo J; Iager, Amy E; Kaiser, German G; Chen, Ying; Cibelli, Jose B

    2009-03-01

    Interspecies somatic cell nuclear transfer (iSCNT) has the potential to become a useful tool to address basic questions about the nucleus-cytoplasm interactions between species. It has also been proposed as an alternative for the preservation of endangered species and to derive autologous embryonic stem cells. Using chimpanzee/ bovine iSCNT as our experimental model we studied the early epigenetic events that take place soon after cell fusion until embryonic genome activation (EGA). Our analysis suggested partial EGA in iSCNT embryos at the eight-cell stage, as indicated by Br-UTP incorporation and expression of chimpanzee embryonic genes. Oct4, Stella, Crabp1, CCNE2, CXCL6, PTGER4, H2AFZ, c-MYC, KLF4, and GAPDH transcripts were expressed, while Nanog, Glut1, DSC2, USF2, Adrbk1, and Lin28 failed to be activated. Although development of iSCNT embryos did not progress beyond the 8- to 16-cell stage, chromatin remodeling events, monitored by H3K27 methylation, H4K5 acetylation, and global DNA methylation, were similar in both intra- and interspecies SCNT embryos. However, bisulfite sequencing indicated incomplete demethylation of Oct4 and Nanog promoters in eight-cell iSCNT embryos. ATP production levels were significantly higher in bovine SCNT embryos than in iSCNT embryos, TUNEL assays did not reveal any difference in the apoptotic status of the nuclei from both types of embryos. Collectively, our results suggest that bovine ooplasm can partially remodel chimpanzee somatic nuclei, and provides insight into some of the current barriers iSCNT must overcome if further embryonic development is to be expected. PMID:19196039

  20. 48 CFR 970.4402-4 - Nuclear material transfers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Nuclear material transfers... 970.4402-4 Nuclear material transfers. (a) Management and operating contractors, in preparing... nuclear material, shall be required to assure that each such subcontract or agreement contains a—...

  1. 48 CFR 970.4402-4 - Nuclear material transfers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Nuclear material transfers... 970.4402-4 Nuclear material transfers. (a) Management and operating contractors, in preparing... nuclear material, shall be required to assure that each such subcontract or agreement contains a—...

  2. Interspecies Dissemination of a Mobilizable Plasmid Harboring blaIMP-19 and the Possibility of Horizontal Gene Transfer in a Single Patient.

    PubMed

    Yamamoto, Masaki; Matsumura, Yasufumi; Gomi, Ryota; Matsuda, Tomonari; Tanaka, Michio; Nagao, Miki; Takakura, Shunji; Uemoto, Shinji; Ichiyama, Satoshi

    2016-09-01

    Carbapenemase-producing Gram-negative bacilli have been a global concern over the past 2 decades because these organisms can cause severe infections with high mortality rates. Carbapenemase genes are often carried by mobile genetic elements, and resistance plasmids can be transferred through conjugation. We conducted whole-genome sequencing (WGS) to demonstrate that the same plasmid harboring a metallo-β-lactamase gene was detected in two different species isolated from a single patient. Metallo-β-lactamase-producing Achromobacter xylosoxidans (KUN4507), non-metallo-β-lactamase-producing Klebsiella pneumoniae (KUN4843), and metallo-β-lactamase-producing K. pneumoniae (KUN5033) were sequentially isolated from a single patient and then analyzed in this study. Antimicrobial susceptibility testing, molecular typing (pulsed-field gel electrophoresis and multilocus sequence typing), and conjugation analyses were performed by conventional methods. Phylogenetic and molecular clock analysis of K. pneumoniae isolates were performed with WGS, and the nucleotide sequences of plasmids detected from these isolates were determined using WGS. Conventional molecular typing revealed that KUN4843 and KUN5033 were identical, whereas the phylogenetic tree analysis revealed a slight difference. These two isolates were separated from the most recent common ancestor 0.74 years before they were isolated. The same resistance plasmid harboring blaIMP-19 was detected in metallo-β-lactamase-producing A. xylosoxidans and K. pneumoniae Although this plasmid was not self-transferable, the conjugation of this plasmid from A. xylosoxidans to non-metallo-β-lactamase-producing K. pneumoniae was successfully performed. The susceptibility patterns for metallo-β-lactamase-producing K. pneumoniae and the transconjugant were similar. These findings supported the possibility of the horizontal transfer of plasmid-borne blaIMP-19 from A. xylosoxidans to K. pneumoniae in a single patient. PMID:27381397

  3. Passive heat transfer means for nuclear reactors

    DOEpatents

    Burelbach, James P.

    1984-01-01

    An improved passive cooling arrangement is disclosed for maintaining adjacent or related components of a nuclear reactor within specified temperature differences. Specifically, heat pipes are operatively interposed between the components, with the vaporizing section of the heat pipe proximate the hot component operable to cool it and the primary condensing section of the heat pipe proximate the other and cooler component operable to heat it. Each heat pipe further has a secondary condensing section that is located outwardly beyond the reactor confinement and in a secondary heat sink, such as air ambient the containment, that is cooler than the other reactor component. Means such as shrouding normally isolated the secondary condensing section from effective heat transfer with the heat sink, but a sensor responds to overheat conditions of the reactor to open the shrouding, which thereby increases the cooling capacity of the heat pipe. By having many such heat pipes, an emergency passive cooling system is defined that is operative without electrical power.

  4. Somatic Cell Nuclear Transfer in the Mouse

    NASA Astrophysics Data System (ADS)

    Kishigami, Satoshi; Wakayama, Teruhiko

    Somatic cell nuclear transfer (SCNT) has become a unique and powerful tool for epigenetic reprogramming research and gene manipulation in animals since “Dolly,” the first animal cloned from an adult cell was reported in 1997. Although the success rates of somatic cloning have been inefficient and the mechanism of reprogramming is still largely unknown, this technique has been proven to work in more than 10 mammalian species. Among them, the mouse provides the best model for both basic and applied research of somatic cloning because of its abounding genetic resources, rapid sexual maturity and propagation, minimal requirements for housing, etc. This chapter describes a basic protocol for mouse cloning using cumulus cells, the most popular cell type for NT, in which donor nuclei are directly injected into the oocyte using a piezo-actuated micromanipulator. In particular, we focus on a new, more efficient mouse cloning protocol using trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, which increases both in vitro and in vivo developmental rates from twofold to fivefold. This new method including TSA will be helpful to establish mouse cloning in many laboratories.

  5. Somatic cell nuclear transfer in the mouse.

    PubMed

    Kishigami, Satoshi; Wakayama, Teruhiko

    2009-01-01

    Somatic cell nuclear transfer (SCNT) has become a unique and powerful tool for epigenetic reprogramming research and gene manipulation in animals since "Dolly," the first animal cloned from an adult cell was reported in 1997. Although the success rates of somatic cloning have been inefficient and the mechanism of reprogramming is still largely unknown, this technique has been proven to work in more than 10 mammalian species. Among them, the mouse provides the best model for both basic and applied research of somatic cloning because of its abounding genetic resources, rapid sexual maturity and propagation, minimal requirements for housing, etc. This chapter describes a basic protocol for mouse cloning using cumulus cells, the most popular cell type for NT, in which donor nuclei are directly injected into the oocyte using a piezo-actuated micromanipulator. In particular, we focus on a new, more efficient mouse cloning protocol using trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, which increases both in vitro and in vivo developmental rates from twofold to fivefold. This new method including TSA will be helpful to establish mouse cloning in many laboratories. PMID:19085136

  6. 10 CFR 70.42 - Transfer of special nuclear material.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Transfer of special nuclear material. 70.42 Section 70.42 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL... agreement with the Commission or the Atomic Energy Commission under section 274 of the Act, if the...

  7. 10 CFR 70.42 - Transfer of special nuclear material.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Transfer of special nuclear material. 70.42 Section 70.42 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL... agreement with the Commission or the Atomic Energy Commission under section 274 of the Act, if the...

  8. 10 CFR 70.42 - Transfer of special nuclear material.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Transfer of special nuclear material. 70.42 Section 70.42 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL... agreement with the Commission or the Atomic Energy Commission under section 274 of the Act, if the...

  9. Interspecies dosimetry of reactive gases

    SciTech Connect

    Miller, F.J.; Overton, J.H.; Gerrity, T.R.; Graham, R.C.

    1987-03-01

    The development of dosimetry models that can provide a description of the uptake and distribution of inhaled compounds throughout the body and the availability of animal toxicological data are integral components for a full evaluation of potential risks associated with human exposure. Interspecies dosimetric comparisons must be approached using a model conceptualization that incorporates the major factors affecting the uptake of the gas, such as respiratory tract morphology, route of breathing, depth and rate of breathing, physicochemical properties of the gas, etc. Modeling efforts thus far have primarily focused on ozone. A comparison of theoretical predictions of delivered dose of ozone to the lower respiratory tract of man shows good agreement with dose estimates derived from experimental measurements. Applications to ozone toxicological data in animals and man have been examined that incorporate the use of dosimetry models in studying quantitative dose-response relationships.

  10. Electronic and Nuclear Factors in Charge and Excitation Transfer

    SciTech Connect

    Piotr Piotrowiak

    2004-09-28

    We report the and/or state of several subprojects of our DOE sponsored research on Electronic and Nuclear Factors in Electron and Excitation Transfer: (1) Construction of an ultrafast Ti:sapphire amplifier. (2) Mediation of electronic interactions in host-guest molecules. (3) Theoretical models of electrolytes in weakly polar media. (4) Symmetry effects in intramolecular excitation transfer.

  11. Orbital transfer of large space structures with nuclear electric rockets

    NASA Technical Reports Server (NTRS)

    Silva, T. H.; Byers, D. C.

    1980-01-01

    This paper discusses the potential application of electric propulsion for orbit transfer of a large spacecraft structure from low earth orbit to geosynchronous altitude in a deployed configuration. The electric power was provided by the spacecraft nuclear reactor space power system on a shared basis during transfer operations. Factors considered with respect to system effectiveness included nuclear power source sizing, electric propulsion thruster concept, spacecraft deployment constraints, and orbital operations and safety. It is shown that the favorable total impulse capability inherent in electric propulsion provides a potential economic advantage over chemical propulsion orbit transfer vehicles by reducing the number of Space Shuttle flights in ground-to-orbit transportation requirements.

  12. INTERSPECIES MODELING OF INHALED PARTICLE DEPOSITION

    EPA Science Inventory

    To evaluate the potential toxic effects of ambient contaminants or therapeutic effects of airborne drugs, inhalation exposure experiments can be performed with surrogate laboratory animals. erein, an interspecies particle deposition theory is presented for physiologically based p...

  13. INTERSPECIES DOSIMETRY MODELS FOR PULMONARY PHARMACOLOGY

    EPA Science Inventory

    Interspecies Dosimetry Models for Pulmonary Pharmacology

    Ted B. Martonen, Jeffry D. Schroeter, and John S. Fleming

    Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangl...

  14. Handmade cloning: the future way of nuclear transfer?

    PubMed

    Vajta, Gábor

    2007-06-01

    The topic of this review is an alternative technique for somatic cell nuclear transfer. Removal of the zona pellucida facilitates manipulations of mammalian oocytes and early embryos, and problems related to their subsequent culture are commonly overestimated. This approach enables radical modifications to somatic cell nuclear transfer, and the handmade cloning (HMC) technique is now successfully applied to an increasing numbers of species. HMC radically decreases costs and the need for a skilled workforce; furthermore, it increases productivity, enables cryopreservation, and results in birth rates comparable, or even higher, than those achievable by micromanipulation-based traditional cloning (TC). The new technique can accelerate technology transfer and standardization and, eventually, might contribute to the widespread application of cloning. Additionally, HMC offers unique possibilities for the automation of somatic cell nuclear transfer. PMID:17434218

  15. Nuclear interlevel transfer driven by electronic transitions

    SciTech Connect

    Solem, J.C.; Rinker, G.

    1985-01-01

    We show how a gamma-ray laser might be made by optically exciting a transfer of population from a long-lived isomer to an energetically adjacent short-lived state of the same nucleus. We compare the advantages of using transitions of high multipolarity versus transitions of low multi-polarity. Preliminary numerical investigations of the mechanism show it to be somewhat favorable. 35 refs., 4 figs.

  16. Disposal modes for Mars transfer nuclear propulsion

    NASA Technical Reports Server (NTRS)

    Stancati, Michael L.; Friedlander, Alan L.

    1991-01-01

    A managed disposal approach is proposed that would place the nuclear stage or vehicle in a highly stable orbit at modest cost to mission performance. The approach requires only a small increase in initial mass in LEO, but should be included in preliminary trajectory design and performance calculations. The mass penalty is expected to be larger for all-up flight profiles, or in cases of high-thrust propulsion systems for the cargo vehicle.

  17. 48 CFR 970.4402-4 - Nuclear material transfers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Nuclear material transfers. 970.4402-4 Section 970.4402-4 Federal Acquisition Regulations System DEPARTMENT OF ENERGY AGENCY SUPPLEMENTARY REGULATIONS DOE MANAGEMENT AND OPERATING CONTRACTS Management and Operating Contractor...

  18. 48 CFR 970.4402-4 - Nuclear material transfers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Nuclear material transfers. 970.4402-4 Section 970.4402-4 Federal Acquisition Regulations System DEPARTMENT OF ENERGY AGENCY SUPPLEMENTARY REGULATIONS DOE MANAGEMENT AND OPERATING CONTRACTS Management and Operating Contractor...

  19. Human somatic cell nuclear transfer is alive and well.

    PubMed

    Cibelli, Jose B

    2014-06-01

    In this issue, Chung et al. (2014) generate human embryonic stem cells by fusing an adult somatic cell to a previously enucleated human oocyte, in agreement with recent reports by the Mitalipov and Egli groups. We can now safely say that human somatic cell nuclear transfer is alive and well. PMID:24905159

  20. Nuclear Waste Cross Site Transfer Pump Operational Resonance Resolution

    SciTech Connect

    HAUCK, F.M.

    1999-12-01

    Two single-volute, multi-stage centrifugal pumps are installed at a nuclear waste transfer station operated by the Department of Energy in Hanford, WA. The two parallel 100% pumps are Variable Frequency Drive operated and designed to transport waste etc.

  1. 48 CFR 970.4402-4 - Nuclear material transfers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Nuclear material transfers. 970.4402-4 Section 970.4402-4 Federal Acquisition Regulations System DEPARTMENT OF ENERGY AGENCY SUPPLEMENTARY REGULATIONS DOE MANAGEMENT AND OPERATING CONTRACTS Management and Operating Contractor...

  2. Theoretical studies on shaking processes in nuclear transfer reactions

    NASA Astrophysics Data System (ADS)

    Sharma, Prashant; Nandi, Tapan

    2015-09-01

    The probabilities of shaking processes during nuclear transfer reactions have been studied using the Mukoyama formalism after the re-examination of formalism for β-decay processes. Electron shakeoff probabilities have been calculated for the α-transfer reaction in the range of Z = 10- 50. The Z-dependence on the shakeoff probabilities so obtained has been represented by an analytical equation with two parameters. The formalism has been applied on a typical nuclear transfer reaction Fe5626 +C126 →Ni6028 +Be84 and it is found that electron shakeup, shakedown and shakeoff probabilities dominate for low l quantum number of the respective shells of the projectile-like fragment ion. However, for a particular value of l these processes show high probabilities for low values of n quantum number.

  3. Nuclear electric power for multimegawatt orbit transfer vehicles

    NASA Technical Reports Server (NTRS)

    Casagrande, R. D.

    1987-01-01

    Multimegawatt nuclear propulsion is an attractive option for orbit transfer vehicles. The masses of these platforms are expected to exceed the capability of a single launch from Earth necessitating assembly in space in a parking orbit. The OTV would transfer the platform from the parking orbit to the operational orbit and then return for the next mission. Electric propulsion is advantageous because of the high specific impulse achieved by the technology, 1000 to 5000 s and beyond, to reduce the propellant required. Nuclear power is attractive as the power system because of the weight savings over solar systems in the multimegawatt regime, and multimegawatts of power are required. A conceptual diagram is shown of an OTV with a command control module using electric thrusters powered from an SP-100 class nuclear reactor power system.

  4. Human Embryonic Stem Cells Derived by Somatic Cell Nuclear Transfer

    PubMed Central

    Tachibana, Masahito; Amato, Paula; Sparman, Michelle; Gutierrez, Nuria Marti; Tippner-Hedges, Rebecca; Ma, Hong; Kang, Eunju; Fulati, Alimujiang; Lee, Hyo-Sang; Sritanaudomchai, Hathaitip; Masterson, Keith; Larson, Janine; Eaton, Deborah; Sadler-Fredd, Karen; Battaglia, David; Lee, David; Wu, Diana; Jensen, Jeffrey; Patton, Phillip; Gokhale, Sumita; Stouffer, Richard L.; Wolf, Don; Mitalipov, Shoukhrat

    2013-01-01

    SUMMARY Reprogramming somatic cells into pluripotent embryonic stem cells (ESCs) by somatic cell nuclear transfer (SCNT) has been envisioned as an approach for generating patient-matched nuclear transfer (NT)-ESCs for studies of disease mechanisms and for developing specific therapies. Past attempts to produce human NT-ESCs have failed secondary to early embryonic arrest of SCNT embryos. Here, we identified premature exit from meiosis in human oocytes and suboptimal activation as key factors that are responsible for these outcomes. Optimized SCNT approaches designed to circumvent these limitations allowed derivation of human NT-ESCs. When applied to premium quality human oocytes, NT-ESC lines were derived from as few as two oocytes. NT-ESCs displayed normal diploid karyotypes and inherited their nuclear genome exclusively from parental somatic cells. Gene expression and differentiation profiles in human NT-ESCs were similar to embryo-derived ESCs, suggesting efficient reprogramming of somatic cells to a pluripotent state. PMID:23683578

  5. Measurement of heat transfer coefficients by nuclear magnetic resonance.

    PubMed

    Gultekin, David H; Gore, John C

    2008-11-01

    We demonstrate an experimental method for the measurement of heat transfer coefficient for a fluid system by magnetic resonance imaging. In this method, the temporal variation of thermally induced nuclear shielding is monitored and the average heat transfer coefficient is measured as a function of fluid velocity. We examine the cases of natural convection and forced convection at fluid velocity up to 0.8 m s(-1). These cases correspond to low dimensionless Biot (Bi) number where the heat transfer is limited by thermal convection. We demonstrate the NMR method for two simple geometries, a cylinder and a sphere, to experimentally determine the heat transfer coefficient (h) in two NMR imaging and spectroscopy systems through measuring three NMR parameters, the chemical shift, magnetization and spin self diffusion coefficient. PMID:18524523

  6. Nuclear transfer preserves the nuclear genome of freeze-dried mouse cells.

    PubMed

    Ono, Tetsuo; Mizutani, Eiji; Li, Chong; Wakayama, Teruhiko

    2008-12-01

    Mouse spermatozoa can be freeze dried without losing genetic integrity and reproductive potential. However, it is not known if freeze-dried mouse cells similarly maintain their genetic integrity and developmental potential following nuclear transfer. Here, we investigated the developmental capacity and embryonic stem (ES) cell derivation of reconstructed oocytes by nuclear transfer using freeze-dried cumulus or ES cells. Cumulus and ES cells were lyophilized overnight and stored at 4 C for up to 1 week. After rehydration, all cells showed membrane damage and were unviable. However, following nuclear transfer, 1-4% of the reconstructed oocytes developed to the blastocyst stage. A total of five nuclear transfer ES (ntES) cell lines were generated from blastocysts and morulae. All ntES cell lines had normal karyotypes and were positive for the ES-cell-specific markers (alkaline phosphatase, Oct3/4 and Nanog). After aggregation of ntES cells with fertilized embryos, chimeric mice with a high level of coat color chimerism were generated. Our findings show that the genomic integrity of cells can be maintained after freeze-drying and that it is possible to produce offspring from the cells using nuclear transfer techniques. PMID:18854641

  7. Heat Transfer Modeling of Dry Spent Nuclear Fuel Storage Facilities

    SciTech Connect

    Lee, S.Y.

    1999-01-13

    The present work was undertaken to provide heat transfer model that accurately predicts the thermal performance of dry spent nuclear fuel storage facilities. One of the storage configurations being considered for DOE Aluminum-clad Spent Nuclear Fuel (Al-SNF), such as the Material and Testing Reactor (MTR) fuel, is in a dry storage facility. To support design studies of storage options a computational and experimental program has been conducted at the Savannah River Site (SRS). The main objective is to develop heat transfer models including natural convection effects internal to an interim dry storage canister and to geological codisposal Waste Package (WP). Calculated temperatures will be used to demonstrate engineering viability of a dry storage option in enclosed interim storage and geological repository WP and to assess the chemical and physical behaviors of the Al-SNF in the dry storage facilities. The current paper describes the modeling approaches and presents the computational results along with the experimental data.

  8. Nuclear Effects in Neutrino Interactions at Low Momentum Transfer

    SciTech Connect

    Miltenberger, Ethan Ryan

    2015-05-01

    This is a study to identify predicted effects of the carbon nucleus environment on neutrino - nucleus interactions with low momentum transfer. A large sample of neutrino interaction data collected by the MINERvA experiment is analyzed to show the distribution of charged hadron energy in a region with low momentum transfer. These distributions reveal a major discrepancy between the data and a popular interaction model with only the simplest Fermi gas nuclear effects. Detailed analysis of systematic uncertainties due to energy scale and resolution can account for only a little of the discrepancy. Two additional nuclear model effects, a suppression/screening effect (RPA), and the addition of a meson exchange current process (MEC), are shown to improve the description of the data.

  9. Nuclear reactor fuel element having improved heat transfer

    DOEpatents

    Garnier, J.E.; Begej, S.; Williford, R.E.; Christensen, J.A.

    1982-03-03

    A nuclear reactor fuel element having improved heat transfer between fuel material and cladding is described. The element consists of an outer cladding tube divided into an upper fuel section containing a central core of fissionable or mixed fissionable and fertile fuel material, slightly smaller in diameter than the inner surface of the cladding tube and a small lower accumulator section, the cladding tube being which is filled with a low molecular weight gas to transfer heat from fuel material to cladding during irradiation. A plurality of essentially vertical grooves in the fuel section extend downward and communicate with the accumulator section. The radial depth of the grooves is sufficient to provide a thermal gradient between the hot fuel surface and the relatively cooler cladding surface to allow thermal segregation to take place between the low molecular weight heat transfer gas and high molecular weight fission product gases produced by the fuel material during irradiation.

  10. Nuclear reactor power for an electrically powered orbital transfer vehicle

    NASA Technical Reports Server (NTRS)

    Jaffe, L.; Beatty, R.; Bhandari, P.; Chow, E.; Deininger, W.; Ewell, R.; Fujita, T.; Grossman, M.; Kia, T.; Nesmith, B.

    1987-01-01

    To help determine the systems requirements for a 300-kWe space nuclear reactor power system, a mission and spacecraft have been examined which utilize electric propulsion and this nuclear reactor power for multiple transfers of cargo between low earth orbit (LEO) and geosynchronous earth orbit (GEO). A propulsion system employing ion thrusters and xenon propellant was selected. Propellant and thrusters are replaced after each sortie to GEO. The mass of the Orbital Transfer Vehicle (OTV), empty and dry, is 11,000 kg; nominal propellant load is 5000 kg. The OTV operates between a circular orbit at 925 km altitude, 28.5 deg inclination, and GEO. Cargo is brought to the OTV by Shuttle and an Orbital Maneuvering Vehicle (OMV); the OTV then takes it to GEO. The OTV can also bring cargo back from GEO, for transfer by OMV to the Shuttle. OTV propellant is resupplied and the ion thrusters are replaced by the OMV before each trip to GEO. At the end of mission life, the OTV's electric propulsion is used to place it in a heliocentric orbit so that the reactor will not return to earth. The nominal cargo capability to GEO is 6000 kg with a transit time of 120 days; 1350 kg can be transferred in 90 days, and 14,300 kg in 240 days. These capabilities can be considerably increased by using separate Shuttle launches to bring up propellant and cargo, or by changing to mercury propellant.

  11. Technological Transfer from Research Nuclear Reactors to New Generation Nuclear Power Reactors

    SciTech Connect

    Radulescu, Laura; Pavelescu, Margarit

    2010-01-21

    The goal of this paper is the analysis of the technological transfer role in the nuclear field, with particular emphasis on nuclear reactors domain. The presentation is sustained by historical arguments. In this frame, it is very important to start with the achievements of the first nuclear systems, for instant those with natural uranium as fuel and heavy water as moderator, following in time through the history until the New Generation Nuclear Power Reactors.Starting with 1940, the accelerated development of the industry has implied the increase of the global demand for energy. In this respect, the nuclear energy could play an important role, being essentially an unlimited source of energy. However, the nuclear option faces the challenges of increasingly demanding safety requirements, economic competitiveness and public acceptance. Worldwide, a significant amount of experience has been accumulated during development, licensing, construction, and operation of nuclear power reactors. The experience gained is a strong basis for further improvements. Actually, the nuclear programs of many countries are addressing the development of advanced reactors, which are intended to have better economics, higher reliability, improved safety, and proliferation-resistant characteristics in order to overcome the current concerns about nuclear power. Advanced reactors, now under development, may help to meet the demand for energy power of both developed and developing countries as well as for district heating, desalination and for process heat.The paper gives historical examples that illustrate the steps pursued from first research nuclear reactors to present advanced power reactors. Emphasis was laid upon the fact that the progress is due to the great discoveries of the nuclear scientists using the technological transfer.

  12. Method for somatic cell nuclear transfer in zebrafish.

    PubMed

    Siripattarapravat, K; Prukudom, S; Cibelli, J

    2016-01-01

    This chapter presents a detailed methodology for somatic cell nuclear transfer-cloning of zebrafish. We aim to place the reader in a virtual lab experience to assist acquisition of the technical skills required for reproducing the published protocol. All materials, including catalog numbers for reagents and techniques for their preparation, are provided. Our protocols describe laser inactivation of egg chromosomes, the transfer of a cell through the oocyte micropyle, and spontaneous activation of the reconstructed embryo. High-quality eggs are the key to cloning success, and Chinook salmon ovarian fluid is indispensable for keeping eggs arrested at the metaphase of meiosis II. This protocol continues to be refined by our laboratory. However, naive investigators should be able to apply it in its present form to generate cloned zebrafish. PMID:27443929

  13. Method for somatic cell nuclear transfer in zebrafish.

    PubMed

    Siripattarapravat, Kannika; Cibelli, Jose B

    2011-01-01

    Somatic cell nuclear transfer (SCNT) has been a well-known technique for decades and widely applied to generate identical animals, including ones with genetic alterations. The system has been demonstrated successfully in zebrafish. The elaborated requirements of SCNT, however, limit reproducibility of the established model to a few groups in zebrafish research community. In this chapter, we meticulously outline each step of the published protocol as well as preparations of equipments and reagents used in zebrafish SCNT. All describable detailed-tips are elaborated in texts and figures. PMID:21924165

  14. In vitro culture and somatic cell nuclear transfer affect imprinting of SNRPN gene in pre- and post-implantation stages of development in cattle

    PubMed Central

    Suzuki, Joao; Therrien, Jacinthe; Filion, France; Lefebvre, Rejean; Goff, Alan K; Smith, Lawrence C

    2009-01-01

    Background Embryo in vitro manipulations during early development are thought to increase mortality by altering the epigenetic regulation of some imprinted genes. Using a bovine interspecies model with a single nucleotide polymorphism, we assessed the imprinting status of the small nuclear ribonucleoprotein polypeptide N (SNRPN) gene in bovine embryos produced by artificial insemination (AI), in vitro culture (IVF) and somatic cell nuclear transfer (SCNT) and correlated allelic expression with the DNA methylation patterns of a differentially methylated region (DMR) located on the SNRPN promoter. Results In the AI group, SNRPN maternal expression is silenced at day 17 and 40 of development and a third of the alleles analyzed are methylated in the DMR. In the IVF group, maternal transcripts were identified at day 17 but methylation levels were similar to the AI group. However, day-40 fetuses in the IVF group showed significantly less methylation when compared to the AI group and SNRPN expression was mostly paternal in all fetal tissues studied, except in placenta. Finally, the SCNT group presented severe loss of DMR methylation in both day-17 embryos and 40 fetuses and biallelic expression was observed in all stages and tissues analyzed. Conclusion Together these results suggest that artificial reproductive techniques, such as prolonged in vitro culture and SCNT, lead to abnormal reprogramming of imprinting of SNRPN gene by altering methylation levels at this locus. PMID:19200381

  15. Propagation of elite rescue dogs by somatic cell nuclear transfer.

    PubMed

    Oh, Hyun Ju; Choi, Jin; Kim, Min Jung; Kim, Geon A; Jo, Young Kwang; Choi, Yoo Bin; Lee, Byeong Chun

    2016-01-01

    The objective of the present study was to compare the efficiency of two oocyte activation culture media to produce cloned dogs from an elite rescue dog and to analyze their behavioral tendencies. In somatic cell nuclear transfer procedure, fused couplets were activated by calcium ionophore treatment for 4 min, cultured in two media: modified synthetic oviduct fluid (mSOF) with 1.9 mmol/L 6-dimethylaminopyridine (DMAP) (SOF-DMAP) or porcine zygote medium (PZM-5) with 1.9 mmol/L DMAP (PZM-DMAP) for 4 h, and then were transferred into recipients. After embryo transfer, pregnancy was detected in one out of three surrogate mothers that received cloned embryos from the PZM-DMAP group (33.3%), and one pregnancy (25%) was detected in four surrogate mothers receiving cloned embryos from the SOF-DMAP group. Each pregnant dog gave birth to one healthy cloned puppy by cesarean section. We conducted the puppy aptitude test with two cloned puppies; the two cloned puppies were classified as the same type, accepting humans and leaders easily. The present study indicated that the type of medium used in 6-DMAP culture did not increase in cloning efficiency and dogs cloned using donor cells derived from one elite dog have similar behavioral tendencies. PMID:26387964

  16. Factors Affecting the Development of Somatic Cell Nuclear Transfer Embryos in Cattle

    PubMed Central

    AKAGI, Satoshi; MATSUKAWA, Kazutsugu; TAKAHASHI, Seiya

    2014-01-01

    Nuclear transfer is a complex multistep procedure that includes oocyte maturation, cell cycle synchronization of donor cells, enucleation, cell fusion, oocyte activation and embryo culture. Therefore, many factors are believed to contribute to the success of embryo development following nuclear transfer. Numerous attempts to improve cloning efficiency have been conducted since the birth of the first sheep by somatic cell nuclear transfer. However, the efficiency of somatic cell cloning has remained low, and applications have been limited. In this review, we discuss some of the factors that affect the developmental ability of somatic cell nuclear transfer embryos in cattle. PMID:25341701

  17. ICESluvan, a 94-Kilobase Mosaic Integrative Conjugative Element Conferring Interspecies Transfer of VanB-Type Glycopeptide Resistance, a Novel Bacitracin Resistance Locus, and a Toxin-Antitoxin Stabilization System

    PubMed Central

    Bjørkeng, Eva K.; Hjerde, Erik; Pedersen, Torunn; Sundsfjord, Arnfinn

    2013-01-01

    A 94-kb integrative conjugative element (ICESluvan) transferable to Enterococcus faecium and Enterococcus faecalis from an animal isolate of Streptococcus lutetiensis consists of a mosaic of genetic fragments from different Gram-positive bacteria. A variant of ICESluvan was confirmed in S. lutetiensis from a patient. A complete Tn5382/Tn1549 with a vanB2 operon is integrated into a streptococcal ICESde3396-like region harboring a putative bacteriophage exclusion system, a putative agglutinin receptor precursor, and key components of a type IV secretion system. Moreover, ICESluvan encodes a putative MobC family mobilization protein and a relaxase and, thus, in total has all genetic components essential for conjugative transfer. A 9-kb element within Tn5382/Tn1549 encodes, among others, putative proteins similar to the TnpX site-specific recombinase in Faecalibacterium and VanZ in Paenibacillus, which may contribute to the detected low-level teicoplanin resistance. Furthermore, ICESluvan encodes a novel bacitracin resistance locus that is associated with reduced susceptibility to bacitracin when transferred to E. faecium. The expression of a streptococcal pezAT toxin-antitoxin-encoding operon of ICESluvan in S. lutetiensis, E. faecium, and E. faecalis was confirmed by reverse transcription (RT)-PCR, indicating an active toxin-antitoxin system which may contribute to stabilizing ICESluvan within new hosts. Junction PCR and DNA sequencing confirmed that ICESluvan excised to form a circular intermediate in S. lutetiensis, E. faecalis, and E. faecium. Transfer between E. faecalis cells was observed in the presence of helper plasmid pIP964. Sequence analysis of the original S. lutetiensis donor and enterococcal transconjugants showed that ICESluvan integrates in a site-specific manner into the C-terminal end of the chromosomal tRNA methyltransferase gene rumA. PMID:24078615

  18. Interspecies Interactions within Oral Microbial Communities

    PubMed Central

    Kuramitsu, Howard K.; He, Xuesong; Lux, Renate; Anderson, Maxwell H.; Shi, Wenyuan

    2007-01-01

    Summary: While reductionism has greatly advanced microbiology in the past 400 years, assembly of smaller pieces just could not explain the whole! Modern microbiologists are learning “system thinking” and “holism.” Such an approach is changing our understanding of microbial physiology and our ability to diagnose/treat microbial infections. This review uses oral microbial communities as a focal point to describe this new trend. With the common name “dental plaque,” oral microbial communities are some of the most complex microbial floras in the human body, consisting of more than 700 different bacterial species. For a very long time, oral microbiologists endeavored to use reductionism to identify the key genes or key pathogens responsible for oral microbial pathogenesis. The limitations of reductionism forced scientists to begin adopting new strategies using emerging concepts such as interspecies interaction, microbial community, biofilms, polymicrobial disease, etc. These new research directions indicate that the whole is much more than the simple sum of its parts, since the interactions between different parts resulted in many new physiological functions which cannot be observed with individual components. This review describes some of these interesting interspecies-interaction scenarios. PMID:18063722

  19. HEAT TRANSFER ANALYSIS FOR NUCLEAR WASTE SOLIDIFICATION CONTAINER

    SciTech Connect

    Lee, S.

    2009-06-01

    The Nuclear Nonproliferation Programs Design Authority is in the design stage of the Waste Solidification Building (WSB) for the treatment and solidification of the radioactive liquid waste streams generated by the Pit Disassembly and Conversion Facility (PDCF) and Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF). The waste streams will be mixed with a cementitious dry mix in a 55-gallon waste container. Savannah River National Laboratory (SRNL) has been performing the testing and evaluations to support technical decisions for the WSB. Engineering Modeling & Simulation Group was requested to evaluate the thermal performance of the 55-gallon drum containing hydration heat source associated with the current baseline cement waste form. A transient axi-symmetric heat transfer model for the drum partially filled with waste form cement has been developed and heat transfer calculations performed for the baseline design configurations. For this case, 65 percent of the drum volume was assumed to be filled with the waste form, which has transient hydration heat source, as one of the baseline conditions. A series of modeling calculations has been performed using a computational heat transfer approach. The baseline modeling results show that the time to reach the maximum temperature of the 65 percent filled drum is about 32 hours when a 43 C initial cement temperature is assumed to be cooled by natural convection with 27 C external air. In addition, the results computed by the present model were compared with analytical solutions. The modeling results will be benchmarked against the prototypic test results. The verified model will be used for the evaluation of the thermal performance for the WSB drum. Detailed results and the cases considered in the calculations will be discussed here.

  20. Gnotobiotic Miniature Pig Interbreed Somatic Cell Nuclear Transfer for Xenotransplantation.

    PubMed

    Hwang, Jeong Ho; Kim, Sang Eun; Gupta, Mukesh Kumar; Lee, HoonTaek

    2016-08-01

    Transgenic animal producing technology has improved consistently over the last couple of decades. Among the available methods, somatic cell nuclear transfer (SCNT) technology was officially the most popular. However, SCNT has low efficiency and requires a highly skilled individual. Additionally, the allo-SCNT nuclear reprogramming mechanism is poorly understood in the gnotobiotic miniature pig, which is a candidate for xenotransplantation, making sampling in oocytes very difficult compared to commercial hybrid pigs. Therefore, interbreed SCNT (ibSCNT), which is a combination of miniature pig and commercial pig (Landrace based), was analyzed and was found to be similar to SCNT in terms of the rate of blastocyst formation (12.6% ± 2.9% vs. 15.5% ± 2.2%; p > 0.05). However, a significantly lower fusion rate was observed in the ibSCNT compared to normal SCNT with Landrace pig somatic cells (29.6% ± 0.8% vs. 65.0% ± 4.9%). Thus, the optimization of fusion parameters was necessary for efficient SCNT. Our results further revealed that ibSCNT by the whole-cell intracytoplasmic injection (WCICI) method had a significantly higher blastocyst forming efficiency than the electrofusion method (31.1 ± 8.5 vs. 15.5% ± 2.2%). The nuclear remodeling and the pattern of changes in acetylation at H3K9 residue were similar in both SCNT and ibSCNT embryos. PMID:27459580

  1. Interspecies interactions and potential Influenza A virus risk in small swine farms in Peru

    PubMed Central

    2012-01-01

    Background The recent avian influenza epidemic in Asia and the H1N1 pandemic demonstrated that influenza A viruses pose a threat to global public health. The animal origins of the viruses confirmed the potential for interspecies transmission. Swine are hypothesized to be prime "mixing vessels" due to the dual receptivity of their trachea to human and avian strains. Additionally, avian and human influenza viruses have previously been isolated in swine. Therefore, understanding interspecies contact on smallholder swine farms and its potential role in the transmission of pathogens such as influenza virus is very important. Methods This qualitative study aimed to determine swine-associated interspecies contacts in two coastal areas of Peru. Direct observations were conducted at both small-scale confined and low-investment swine farms (n = 36) and in open areas where swine freely range during the day (n = 4). Interviews were also conducted with key stakeholders in swine farming. Results In both locations, the intermingling of swine and domestic birds was common. An unexpected contact with avian species was that swine were fed poultry mortality in 6/20 of the farms in Chancay. Human-swine contacts were common, with a higher frequency on the confined farms. Mixed farming of swine with chickens or ducks was observed in 36% of all farms. Human-avian interactions were less frequent overall. Use of adequate biosecurity and hygiene practices by farmers was suboptimal at both locations. Conclusions Close human-animal interaction, frequent interspecies contacts and suboptimal biosecurity and hygiene practices pose significant risks of interspecies influenza virus transmission. Farmers in small-scale swine production systems constitute a high-risk population and need to be recognized as key in preventing interspecies pathogen transfer. A two-pronged prevention approach, which offers educational activities for swine farmers about sound hygiene and biosecurity practices and

  2. Interspecies genetics of eating disorder traits.

    PubMed

    Kas, Martien J H; Kaye, Walter H; Foulds Mathes, Wendy; Bulik, Cynthia M

    2009-04-01

    Family and twin studies have indicated that genetic factors play a role in the development of eating disorders, such as anorexia and bulimia nervosa, but novel views and tools may enhance the identification of neurobiological mechanisms underlying these conditions. Here we propose an integrative genetic approach to reveal novel biological substrates of eating disorder traits analogous in mouse and human. For example, comparable to behavioral hyperactivity that is observed in 40-80% of anorexia nervosa patients, inbred strains of mice with different genetic backgrounds are differentially susceptible to develop behavioral hyperactivity when food restricted. In addition, a list of characteristics that are relevant to eating disorders and approaches to their measurement in humans together with potential analogous rodent models has been generated. Interspecies genetics of neurobehavioral characteristics of eating disorders has the potential to open new roads to identify and functionally test genetic pathways that influence neurocircuits relevant for these heterogeneous psychiatric disorders. PMID:18646037

  3. Interspecies modeling of inhaled particle deposition patterns

    SciTech Connect

    Martonen, T.B.; Zhang, Z.; Yang, Y.

    1992-01-01

    To evaluate the potential toxic effects of ambient contaminants or therapeutic effects of airborne drugs, inhalation exposure experiments can be performed with surrogate laboratory animals. Herein, an interspecies particle deposition theory is presented for physiologically based pharmacokinetic modeling. It is derived to improve animal testing protocols. The computer code describes the behavior and fate of particles in the lungs of human subjects and a selected surrogate, the laboratory rat. In the simulations CO2 is integrated with exposure chamber atmospheres, and its concentrations regulated to produce rat breathing profiles corresponding to selected levels of human physical activity. The dosimetric model is used to calculate total, compartmental (i.e., tracheobronchial and pulmonary), and localized distribution patterns of inhaled particles in rats and humans for comparable ventilatory conditions. It is demonstrated that the model can be used to predetermine the exposure conditions necessary to produce deposition patterns in rats that are equivalent to those in humans at prescribed physical activities.

  4. Nuclear remodeling in bovine somatic cell nuclear transfer embryos using MG132-treated recipient oocytes.

    PubMed

    Le Bourhis, Daniel; Beaujean, Nathalie; Ruffini, Sylvie; Vignon, Xavier; Gall, Laurence

    2010-12-01

    The early events in the nuclear reprogramming process during somatic cell nuclear transfer (SCNT) consist of morphological remodeling of the donor nucleus including premature chromosome condensation (PCC). In the present study, the objective was to increase oocyte M-Phase Promoting Factor (MPF) kinase activity and to examine the fate of the donor nucleus and the development of SCNT embryos thereafter. Indeed, in controls, recipient oocytes activated upon nuclear transfer, undergo a decrease in MPF activity, responsible for the inability to promote PCC in 77.8% of reconstituted embryos. Here we showed that exposure of the recipient oocyte to the proteasome inhibitor MG132 prior to fusion inhibited the degradation of cyclin B, which normally occurred immediately after activation by electro stimulation, and therefore sustained a high level of MPF. Treatment with MG132 also significantly increased the percentage of SCNT embryos with PCC when compared to the nontreated SCNT control embryos (94.1 vs. 22.2%, respectively, p < 0.01). The frequency of development to the blastocyst stage did not differ between MG132-treated or untreated recipient oocytes. However, we observed a significant increase of the total cells number in embryos produced after MG132 treatment. Investigation of the global nuclear organization by immunodetection of heterochromatin protein 1 (CBX1) showed that SCNT embryos derived from MG132-treated recipient oocytes displayed organization patterns similar to the ones observed in IVF embryos in contrast to the nontreated SCNT controls. Taken together, these results suggest that the PCC induced by MG132 treatment allows reorganization of the chromatin at an appropriate time potentially, leading to better reprogramming. PMID:21108537

  5. Natural convection heat transfer within horizontal spent nuclear fuel assemblies

    SciTech Connect

    Canaan, R.E.

    1995-12-01

    Natural convection heat transfer is experimentally investigated in an enclosed horizontal rod bundle, which characterizes a spent nuclear fuel assembly during dry storage and/or transport conditions. The basic test section consists of a square array of sixty-four stainless steel tubular heaters enclosed within a water-cooled rectangular copper heat exchanger. The heaters are supplied with a uniform power generation per unit length while the surrounding enclosure is maintained at a uniform temperature. The test section resides within a vacuum/pressure chamber in order to subject the assembly to a range of pressure statepoints and various backfill gases. The objective of this experimental study is to obtain convection correlations which can be used in order to easily incorporate convective effects into analytical models of horizontal spent fuel systems, and also to investigate the physical nature of natural convection in enclosed horizontal rod bundles in general. The resulting data consist of: (1) measured temperatures within the assembly as a function of power, pressure, and backfill gas; (2) the relative radiative contribution for the range of observed temperatures; (3) correlations of convective Nusselt number and Rayleigh number for the rod bundle as a whole; and (4) correlations of convective Nusselt number as a function of Rayleigh number for individual rods within the array.

  6. 10 CFR 73.28 - Security background checks for secure transfer of nuclear materials.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Security background checks for secure transfer of nuclear materials. 73.28 Section 73.28 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection of Special Nuclear Material in Transit § 73.28...

  7. 10 CFR 73.28 - Security background checks for secure transfer of nuclear materials.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Security background checks for secure transfer of nuclear materials. 73.28 Section 73.28 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection of Special Nuclear Material in Transit § 73.28...

  8. 10 CFR 73.28 - Security background checks for secure transfer of nuclear materials.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Security background checks for secure transfer of nuclear materials. 73.28 Section 73.28 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection of Special Nuclear Material in Transit § 73.28...

  9. 10 CFR 73.28 - Security background checks for secure transfer of nuclear materials.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Security background checks for secure transfer of nuclear materials. 73.28 Section 73.28 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection of Special Nuclear Material in Transit § 73.28...

  10. 10 CFR 73.28 - Security background checks for secure transfer of nuclear materials.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Security background checks for secure transfer of nuclear materials. 73.28 Section 73.28 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection of Special Nuclear Material in Transit § 73.28...

  11. Histone deacetylase inhibitor improves the development and acetylation levels of cat-cow interspecies cloned embryos.

    PubMed

    Wittayarat, Manita; Sato, Yoko; Do, Lanh Thi Kim; Morita, Yasuhiro; Chatdarong, Kaywalee; Techakumphu, Mongkol; Taniguchi, Masayasu; Otoi, Takeshige

    2013-08-01

    Abnormal epigenetic reprogramming, such as histone acetylation, might cause low efficiency of interspecies somatic cell nuclear transfer (iSCNT). This study was conducted to evaluate the effects of trichostatin A (TSA) on the developmental competence and histone acetylation of iSCNT embryos reconstructed from cat somatic cells and bovine cytoplasm. The iSCNT cat and parthenogenetic bovine embryos were treated with various concentrations of TSA (0, 25, 50, or 100 nM) for 24 h, respectively, following fusion and activation. Treatment with 50 nM TSA produced significantly higher rates of cleavage and blastocyst formation (84.3% and 4.6%, respectively) of iSCNT embryos than the rates of non-TSA-treated iSCNT embryos (63.8% and 0%, respectively). Similarly, the treatment of 50 nM TSA increased the blastocyst formation rate of parthenogenetic bovine embryos. The acetylation levels of histone H3 lysine 9 (H3K9) in the iSCNT embryos with the treatment of 50 nM TSA were similar to those of in vitro-fertilized embryos and significantly higher (p<0.05) than those of non-TSA-treated iSCNT embryos (control), irrespective of the embryonic development stage (two-cell, four-cell, and eight-cell stages). These results indicated that the treatment of 50 nM TSA postfusion was beneficial for development to the blastocyst stage of iSCNT cat embryos and correlated with the increasing levels of acetylation at H3K9. PMID:23790014

  12. Nuclear Technology Series. Course 4: Heat Transfer and Fluid Flow.

    ERIC Educational Resources Information Center

    Center for Occupational Research and Development, Inc., Waco, TX.

    This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

  13. Assessing Uncertainty of Interspecies Correlation Estimation Models for Aromatic Compounds

    EPA Science Inventory

    We developed Interspecies Correlation Estimation (ICE) models for aromatic compounds containing 1 to 4 benzene rings to assess uncertainty in toxicity extrapolation in two data compilation approaches. ICE models are mathematical relationships between surrogate and predicted test ...

  14. Genome sequence of the lager brewing yeast, an interspecies hybrid.

    PubMed

    Nakao, Yoshihiro; Kanamori, Takeshi; Itoh, Takehiko; Kodama, Yukiko; Rainieri, Sandra; Nakamura, Norihisa; Shimonaga, Tomoko; Hattori, Masahira; Ashikari, Toshihiko

    2009-04-01

    This work presents the genome sequencing of the lager brewing yeast (Saccharomyces pastorianus) Weihenstephan 34/70, a strain widely used in lager beer brewing. The 25 Mb genome comprises two nuclear sub-genomes originating from Saccharomyces cerevisiae and Saccharomyces bayanus and one circular mitochondrial genome originating from S. bayanus. Thirty-six different types of chromosomes were found including eight chromosomes with translocations between the two sub-genomes, whose breakpoints are within the orthologous open reading frames. Several gene loci responsible for typical lager brewing yeast characteristics such as maltotriose uptake and sulfite production have been increased in number by chromosomal rearrangements. Despite an overall high degree of conservation of the synteny with S. cerevisiae and S. bayanus, the syntenies were not well conserved in the sub-telomeric regions that contain lager brewing yeast characteristic and specific genes. Deletion of larger chromosomal regions, a massive unilateral decrease of the ribosomal DNA cluster and bilateral truncations of over 60 genes reflect a post-hybridization evolution process. Truncations and deletions of less efficient maltose and maltotriose uptake genes may indicate the result of adaptation to brewing. The genome sequence of this interspecies hybrid yeast provides a new tool for better understanding of lager brewing yeast behavior in industrial beer production. PMID:19261625

  15. Cloned embryos from semen. Part 2: Intergeneric nuclear transfer of semen-derived eland (Taurotragus oryx) epithelial cells into bovine oocytes

    USGS Publications Warehouse

    Nel-Themaat, L.; Gomez, M.C.; Pope, C.E.; Lopez, M.; Wirtu, G.; Jenkins, J.A.; Cole, A.; Dresser, B.L.; Bondioli, K.R.; Godke, R.A.

    2008-01-01

    The production of cloned offspring by nuclear transfer (NT) of semen-derived somatic cells holds considerable potential for the incorporation of novel genes into endangered species populations. Because oocytes from endangered species are scarce, domestic species oocytes are often used as cytoplasts for interspecies NT. In the present study, epithelial cells isolated from eland semen were used for intergeneric transfer (IgNT) into enucleated bovine oocytes and compared with bovine NT embryos. Cleavage rates of bovine NT and eland IgNT embryos were similar (80 vs. 83%, respectively; p > 0.05); however, development to the morula and blastocyst stage was higher for bovine NT embryos (38 and 21%, respectively; p < 0.0001), than for eland IgNT embryos (0.5 and 0%, respectively). DNA synthesis was not observed in either bovine NT or eland IgNT cybrids before activation, but in 75 and 70% of bovine NT and eland igNT embryos, respectively, cell-cycle resumption was observed at 16 h postactivation (hpa). For eland IgNT embryos, 13% had ???8 cells at 84 hpa, while 32% of the bovine NT embryos had ???8 cells at the same interval. However, 100 and 66% of bovine NT and eland IgNT embryos, respectively, that had ???8 cells synthesized DNA. From these results we concluded that (1) semen-derived epithelial cell nuclei can interact and be transcriptionally controlled by bovine cytoplast, (2) the first cell-cycle occurred in IgNT embryos, (3) a high frequency of developmental arrest occurs before the eight-cell stage in IgNT embryos, and (4) IgNT embryos that progress through the early cleavage stage arrest can (a) synthesize DNA, (b) progress through subsequent cell cycles, and (c) may have the potential to develop further. ?? 2008 Mary Ann Liebert, Inc.

  16. Cloned embryos from semen. Part 2: intergeneric nuclear transfer of semen-derived eland (Taurotragus oryx) epithelial cells into bovine oocytes.

    PubMed

    Nel-Themaat, Liesl; Gómez, Martha C; Pope, C Earle; Lopez, Monica; Wirtu, Gemechu; Jenkins, Jill A; Cole, Alex; Dresser, Betsy L; Bondioli, Kenneth R; Godke, Robert A

    2008-03-01

    The production of cloned offspring by nuclear transfer (NT) of semen-derived somatic cells holds considerable potential for the incorporation of novel genes into endangered species populations. Because oocytes from endangered species are scarce, domestic species oocytes are often used as cytoplasts for interspecies NT. In the present study, epithelial cells isolated from eland semen were used for intergeneric transfer (IgNT) into enucleated bovine oocytes and compared with bovine NT embryos. Cleavage rates of bovine NT and eland IgNT embryos were similar (80 vs. 83%, respectively; p > 0.05); however, development to the morula and blastocyst stage was higher for bovine NT embryos (38 and 21%, respectively; p < 0.0001), than for eland IgNT embryos (0.5 and 0%, respectively). DNA synthesis was not observed in either bovine NT or eland IgNT cybrids before activation, but in 75 and 70% of bovine NT and eland igNT embryos, respectively, cell-cycle resumption was observed at 16 h postactivation (hpa). For eland IgNT embryos, 13% had > or = 8 cells at 84 hpa, while 32% of the bovine NT embryos had > or = 8 cells at the same interval. However, 100 and 66% of bovine NT and eland IgNT embryos, respectively, that had > or = 8 cells synthesized DNA. From these results we concluded that (1) semen-derived epithelial cell nuclei can interact and be transcriptionally controlled by bovine cytoplast, (2) the first cell-cycle occurred in IgNT embryos, (3) a high frequency of developmental arrest occurs before the eight-cell stage in IgNT embryos, and (4) IgNT embryos that progress through the early cleavage stage arrest can (a) synthesize DNA, (b) progress through subsequent cell cycles, and (c) may have the potential to develop further. PMID:18241126

  17. Heat Transfer Phenomena in Supercritical Water Nuclear Reactors

    SciTech Connect

    Mark H. Anderson; MichaelL. Corradini; Riccardo Bonazza; Jeremy R. Licht

    2007-10-03

    A supercritical water heat transfer facility has been built at the University of Wisconsin to study heat transfer in ancircular and square annular flow channel. A series of integral heat transfer measurements has been carried out over a wide range of heat flux, mas velocity and bulk water temperatures at a pressure of 25 MPa. The circular annular test section geometry is a 1.07 cm diameter heater rod within a 4.29 diameter flow channel.

  18. Molten Chloride Salts for Heat Transfer in Nuclear Systems

    NASA Astrophysics Data System (ADS)

    Ambrosek, James Wallace

    2011-12-01

    A forced convection loop was designed and constructed to examine the thermal-hydraulic performance of molten KCl-MgCl2 (68-32 at %) salt for use in nuclear co-generation facilities. As part of this research, methods for prediction of the thermo-physical properties of salt mixtures for selection of the coolant salt were studied. In addition, corrosion studies of 10 different alloys were exposed to the KCl-MgCl2 to determine a suitable construction material for the loop. Using experimental data found in literature for unary and binary salt systems, models were found, or developed to extrapolate the available experimental data to unstudied salt systems. These property models were then used to investigate the thermo-physical properties of the LINO3-NaNO3-KNO 3-Ca(NO3), system used in solar energy applications. Using these models, the density, viscosity, adiabatic compressibility, thermal conductivity, heat capacity, and melting temperatures of higher order systems can be approximated. These models may be applied to other molten salt systems. Coupons of 10 different alloys were exposed to the chloride salt for 100 hours at 850°C was undertaken to help determine with which alloy to construct the loop. Of the alloys exposed, Haynes 230 had the least amount of weight loss per area. Nickel and Hastelloy N performed best based on maximum depth of attack. Inconel 625 and 718 had a nearly uniform depletion of Cr from the surface of the sample. All other alloys tested had depletion of Cr along the grain boundaries. The Nb in Inconel 625 and 718 changed the way the Cr is depleted in these alloys. Grain-boundary engineering (GBE) of Incoloy 800H improved the corrosion resistance (weight loss and maximum depth of attack) by nearly 50% as compared to the as-received Incoloy 800H sample. A high temperature pump, thermal flow meter, and pressure differential device was designed, constructed and tested for use in the loop, The heat transfer of the molten chloride salt was found to

  19. Human somatic cell nuclear transfer and reproductive cloning: an Ethics Committee opinion.

    PubMed

    2016-04-01

    This document presents arguments that conclude that it is unethical to use somatic cell nuclear transfer (SCNT) for infertility treatment due to concerns about safety; the unknown impact of SCNT on children, families, and society; and the availability of other ethically acceptable means of assisted reproduction. This document replaces the ASRM Ethics Committee report titled, "Human somatic cell nuclear transfer and cloning," last published in Fertil Steril 2012;98:804-7. PMID:26746137

  20. Generation of cloned mice and nuclear transfer embryonic stem cell lines from urine-derived cells.

    PubMed

    Mizutani, Eiji; Torikai, Kohei; Wakayama, Sayaka; Nagatomo, Hiroaki; Ohinata, Yasuhide; Kishigami, Satoshi; Wakayama, Teruhiko

    2016-01-01

    Cloning animals by nuclear transfer provides the opportunity to preserve endangered mammalian species. However, there are risks associated with the collection of donor cells from the body such as accidental injury to or death of the animal. Here, we report the production of cloned mice from urine-derived cells collected noninvasively. Most of the urine-derived cells survived and were available as donors for nuclear transfer without any pretreatment. After nuclear transfer, 38-77% of the reconstructed embryos developed to the morula/blastocyst, in which the cell numbers in the inner cell mass and trophectoderm were similar to those of controls. Male and female cloned mice were delivered from cloned embryos transferred to recipient females, and these cloned animals grew to adulthood and delivered pups naturally when mated with each other. The results suggest that these cloned mice had normal fertility. In additional experiments, 26 nuclear transfer embryonic stem cell lines were established from 108 cloned blastocysts derived from four mouse strains including inbreds and F1 hybrids with relatively high success rates. Thus, cells derived from urine, which can be collected noninvasively, may be used in the rescue of endangered mammalian species by using nuclear transfer without causing injury to the animal. PMID:27033801

  1. Generation of cloned mice and nuclear transfer embryonic stem cell lines from urine-derived cells

    PubMed Central

    Mizutani, Eiji; Torikai, Kohei; Wakayama, Sayaka; Nagatomo, Hiroaki; Ohinata, Yasuhide; Kishigami, Satoshi; Wakayama, Teruhiko

    2016-01-01

    Cloning animals by nuclear transfer provides the opportunity to preserve endangered mammalian species. However, there are risks associated with the collection of donor cells from the body such as accidental injury to or death of the animal. Here, we report the production of cloned mice from urine-derived cells collected noninvasively. Most of the urine-derived cells survived and were available as donors for nuclear transfer without any pretreatment. After nuclear transfer, 38–77% of the reconstructed embryos developed to the morula/blastocyst, in which the cell numbers in the inner cell mass and trophectoderm were similar to those of controls. Male and female cloned mice were delivered from cloned embryos transferred to recipient females, and these cloned animals grew to adulthood and delivered pups naturally when mated with each other. The results suggest that these cloned mice had normal fertility. In additional experiments, 26 nuclear transfer embryonic stem cell lines were established from 108 cloned blastocysts derived from four mouse strains including inbreds and F1 hybrids with relatively high success rates. Thus, cells derived from urine, which can be collected noninvasively, may be used in the rescue of endangered mammalian species by using nuclear transfer without causing injury to the animal. PMID:27033801

  2. A background to nuclear transfer and its applications in agriculture and human therapeutic medicine*

    PubMed Central

    Campbell, Keith HS

    2002-01-01

    The development of a single celled fertilized zygote to an animal capable of reproduction involves not only cell division but the differentiation or specialization to numerous cell types forming each tissue and organ of the adult animal. The technique of nuclear transfer allows the reconstruction of an embryo by the transfer of genetic material from a single donor cell, to an unfertilized egg from which the genetic material has been removed. Successful development of live offspring from such embryos demonstrates that the differentiated state of the donor nucleus is not fixed and can be reprogrammed by the egg cytoplasm to control embryo and fetal development. Nuclear transfer has many applications in agriculture and human medicine. This article will review some of the factors associated with the success of embryo development following nuclear transfer and outline the potential uses of the technology. PMID:12033731

  3. Interspecies interactions are an integral determinant of microbial community dynamics.

    PubMed

    Aziz, Fatma A A; Suzuki, Kenshi; Ohtaki, Akihiro; Sagegami, Keita; Hirai, Hidetaka; Seno, Jun; Mizuno, Naoko; Inuzuka, Yuma; Saito, Yasuhisa; Tashiro, Yosuke; Hiraishi, Akira; Futamata, Hiroyuki

    2015-01-01

    This study investigated the factors that determine the dynamics of bacterial communities in a complex system using multidisciplinary methods. Since natural and engineered microbial ecosystems are too complex to study, six types of synthetic microbial ecosystems (SMEs) were constructed under chemostat conditions with phenol as the sole carbon and energy source. Two to four phenol-degrading, phylogenetically and physiologically different bacterial strains were used in each SME. Phylogeny was based on the nucleotide sequence of 16S rRNA genes, while physiologic traits were based on kinetic and growth parameters on phenol. Two indices, J parameter and "interspecies interaction," were compared to predict which strain would become dominant in an SME. The J parameter was calculated from kinetic and growth parameters. On the other hand, "interspecies interaction," a new index proposed in this study, was evaluated by measuring the specific growth activity, which was determined on the basis of relative growth of a strain with or without the supernatant prepared from other bacterial cultures. Population densities of strains used in SMEs were enumerated by real-time quantitative PCR (qPCR) targeting the gene encoding the large subunit of phenol hydroxylase and were compared to predictions made from J parameter and interspecies interaction calculations. In 4 of 6 SEMs tested the final dominant strain shown by real-time qPCR analyses coincided with the strain predicted by both the J parameter and the interspecies interaction. However, in SMEII-2 and SMEII-3 the final dominant Variovorax strains coincided with prediction of the interspecies interaction but not the J parameter. These results demonstrate that the effects of interspecies interactions within microbial communities contribute to determining the dynamics of the microbial ecosystem. PMID:26539177

  4. Interspecies interactions are an integral determinant of microbial community dynamics

    PubMed Central

    Aziz, Fatma A. A.; Suzuki, Kenshi; Ohtaki, Akihiro; Sagegami, Keita; Hirai, Hidetaka; Seno, Jun; Mizuno, Naoko; Inuzuka, Yuma; Saito, Yasuhisa; Tashiro, Yosuke; Hiraishi, Akira; Futamata, Hiroyuki

    2015-01-01

    This study investigated the factors that determine the dynamics of bacterial communities in a complex system using multidisciplinary methods. Since natural and engineered microbial ecosystems are too complex to study, six types of synthetic microbial ecosystems (SMEs) were constructed under chemostat conditions with phenol as the sole carbon and energy source. Two to four phenol-degrading, phylogenetically and physiologically different bacterial strains were used in each SME. Phylogeny was based on the nucleotide sequence of 16S rRNA genes, while physiologic traits were based on kinetic and growth parameters on phenol. Two indices, J parameter and “interspecies interaction,” were compared to predict which strain would become dominant in an SME. The J parameter was calculated from kinetic and growth parameters. On the other hand, “interspecies interaction,” a new index proposed in this study, was evaluated by measuring the specific growth activity, which was determined on the basis of relative growth of a strain with or without the supernatant prepared from other bacterial cultures. Population densities of strains used in SMEs were enumerated by real-time quantitative PCR (qPCR) targeting the gene encoding the large subunit of phenol hydroxylase and were compared to predictions made from J parameter and interspecies interaction calculations. In 4 of 6 SEMs tested the final dominant strain shown by real-time qPCR analyses coincided with the strain predicted by both the J parameter and the interspecies interaction. However, in SMEII-2 and SMEII-3 the final dominant Variovorax strains coincided with prediction of the interspecies interaction but not the J parameter. These results demonstrate that the effects of interspecies interactions within microbial communities contribute to determining the dynamics of the microbial ecosystem. PMID:26539177

  5. Thermoacoustic sensor for nuclear fuel temperaturemonitoring and heat transfer enhancement

    SciTech Connect

    James A. Smith; Dale K. Kotter; Randall A. Alli; Steven L. Garrett

    2013-05-01

    A new acoustical sensing system for the nuclear power industry has been developed at The Pennsylvania State University in collaboration with Idaho National Laboratories. This sensor uses the high temperatures of nuclear fuel to convert a nuclear fuel rod into a standing-wave thermoacoustic engine. When a standing wave is generated, the sound wave within the fuel rod will be propagated, by acoustic radiation, through the cooling fluid within the reactor or spent fuel pool and can be monitored a remote location external to the reactor. The frequency of the sound can be correlated to an effective temperature of either the fuel or the surrounding coolant. We will present results for a thermoacoustic resonator built into a Nitonic-60 (stainless steel) fuel rod that requires only one passive component and no heat exchangers.

  6. Ultrafast Charge Transfer of a Valence Double Hole in Glycine Driven Exclusively by Nuclear Motion

    NASA Astrophysics Data System (ADS)

    Li, Zheng; Vendrell, Oriol; Santra, Robin

    2015-10-01

    We explore theoretically the ultrafast transfer of a double electron hole between the functional groups of glycine after K -shell ionization and subsequent Auger decay. Although a large energy gap of about 15 eV initially exists between the two electronic states involved and coherent electronic dynamics play no role in the hole transfer, we find that the double hole is transferred within 3 to 4 fs between both functional ends of the glycine molecule driven solely by specific nuclear displacements and non-Born-Oppenheimer effects. The nuclear displacements along specific vibrational modes are of the order of 15% of a typical chemical bond between carbon, oxygen, and nitrogen atoms and about 30% for bonds involving hydrogen atoms. The time required for the hole transfer corresponds to less than half a vibrational period of the involved nuclear modes. This finding challenges the common wisdom that nuclear dynamics of the molecular skeleton are unimportant for charge transfer processes at the few-femtosecond time scale and shows that they can even play a prominent role. It also indicates that in x-ray imaging experiments, in which ionization is unavoidable, valence electron redistribution caused by nuclear dynamics might be much faster than previously anticipated. Thus, non-Born-Oppenheimer effects may affect the apparent electron densities extracted from such measurements.

  7. Fatal attraction: Explaining Russia's sensitive nuclear transfers to Iran

    NASA Astrophysics Data System (ADS)

    Kuchinsky, Leah R.

    This paper explores Russia's sensitive nuclear assistance to Iran in an effort to determine why a supplier state might proliferate against its own apparent security interests. The goal is to help readers understand the supply-side dynamics of nuclear proliferation. Through careful reconstruction of the historical narrative, using open source data, this study tests the plausibility of a "fatalistic calculus" explanation, identified by Stephen Sestanovich as a possible driver for Russia's behavior. According to the hypothesis, Russia has cooperated with Iran as a way both to stay in the good graces of a neighbor that is suspected of developing nuclear weapons and to win short-term influence and profits. The paper also examines the role of other factors advanced in the existing supply-side literature, such as economic motives identified by physicist and nonproliferation scholar David Albright. The findings show that bureaucratic, economic and fatalistic factors have each played a role in motivating Russia's cooperation with Iran, with their relative importance shifting over time. Fatalism begets a strategy of Russian "minimaxing," in the lexicon of Russia scholar Robert Freedman, wherein Russia attempts to minimize damage to its relationship with the U.S. while maximizing influence in Iran via nuclear cooperation. Fatalism, as actualized by minimaxing, best explains Russia's behavior after former Russian president Vladmir Putin came to power, when the bureaucratic and economic arguments become less cogent.

  8. Modeling transient heat transfer in nuclear waste repositories.

    PubMed

    Yang, Shaw-Yang; Yeh, Hund-Der

    2009-09-30

    The heat of high-level nuclear waste may be generated and released from a canister at final disposal sites. The waste heat may affect the engineering properties of waste canisters, buffers, and backfill material in the emplacement tunnel and the host rock. This study addresses the problem of the heat generated from the waste canister and analyzes the heat distribution between the buffer and the host rock, which is considered as a radial two-layer heat flux problem. A conceptual model is first constructed for the heat conduction in a nuclear waste repository and then mathematical equations are formulated for modeling heat flow distribution at repository sites. The Laplace transforms are employed to develop a solution for the temperature distributions in the buffer and the host rock in the Laplace domain, which is numerically inverted to the time-domain solution using the modified Crump method. The transient temperature distributions for both the single- and multi-borehole cases are simulated in the hypothetical geological repositories of nuclear waste. The results show that the temperature distributions in the thermal field are significantly affected by the decay heat of the waste canister, the thermal properties of the buffer and the host rock, the disposal spacing, and the thickness of the host rock at a nuclear waste repository. PMID:19376651

  9. Development of Interspecies Correlation Models for Petroleum Hydrocarbons

    EPA Science Inventory

    Estimating the consequences of petroleum products to water column organisms has commonly been hampered by limited acute toxicity data, which exists only for a relatively small number of test species. In this study, we developed petroleum-specific Interspecies Correlation Estimati...

  10. Single and Multi-Nucleon Transfer Reactions for Nuclear Moment Studies Toward Radioactive-Ion Beams

    SciTech Connect

    Lozeva, R. L.; Georgiev, G. P.; Audi, G.; Cabaret, S.; Fiori, E.; Gaulard, C.; Hauschilda, K.; Lopez-Martens, A.; Risegari, L.; Blazhev, A.; Jolie, J.; Moschner, K.; Zell, K.-O.; Daugas, J.-M.; Faul, T.; Morel, P.; Roig, O.; Ferraton, M.; Ibrahim, F.

    2010-04-30

    This study is a part of an experimental program to measure nuclear moments in transfer reactions. It aims to probe for a first time the nuclear -spin orientation in multi-nucleon transfer. Fist experiments were performed to measure the quadrupole moment of an isomeric state in {sup 66}Cu (I{sup p}i 6{sup -}, E{sub x} = 1154 keV, T{sub 1/2} = 595(20) ns) in single nucleon transfer and the population of mus isomers in {sup 66}Cu and {sup 63}Ni in multi-nucleon transfer. The experimentally tested methodology allows broad applications toward more exotic species and feasibility of these reactions to produce species away from stability.

  11. Treating humanity as an inviolable end: an analysis of contraception and altered nuclear transfer.

    PubMed

    Masek, Lawrence

    2008-04-01

    I argue that contraception is morally wrong but that periodic abstinence (or natural family planning) is not. Further, I argue that altered nuclear transfer -- a proposed technique for creating human stem cells without destroying human embryos -- is morally wrong for the same reason that contraception is. Contrary to what readers might expect, my argument assumes nothing about the morality of cloning or abortion and requires no premises about God or natural teleology. Instead, I argue that contraception and altered nuclear transfer are morally wrong because they fail to treat humanity as an inviolable end. PMID:18480499

  12. Activation of bovine somatic cell nuclear transfer embryos by PLCZ cRNA injection.

    PubMed

    Ross, Pablo J; Rodriguez, Ramon M; Iager, Amy E; Beyhan, Zeki; Wang, Kai; Ragina, Neli P; Yoon, Sook-Young; Fissore, Rafael A; Cibelli, Jose B

    2009-03-01

    The production of cloned animals by the transfer of a differentiated somatic cell into an enucleated oocyte circumvents fertilization. During fertilization, the sperm delivers a sperm-specific phospholipase C (PLCZ) that is responsible for triggering Ca(2)(+) oscillations and oocyte activation. During bovine somatic cell nuclear transfer (SCNT), oocyte activation is artificially achieved by combined chemical treatments that induce a monotonic rise in intracellular Ca(2)(+) and inhibit either phosphorylation or protein synthesis. In this study, we tested the hypothesis that activation of bovine nuclear transfer embryos by PLCZ improves nuclear reprogramming. Injection of PLCZ cRNA into bovine SCNT units induced Ca(2)(+) oscillations similar to those observed after fertilization and supported high rates of blastocyst development similar to that seen in embryos produced by IVF. Furthermore, gene expression analysis at the eight-cell and blastocyst stages revealed a similar expression pattern for a number of genes in both groups of embryos. Lastly, levels of trimethylated lysine 27 at histone H3 in blastocysts were higher in bovine nuclear transfer embryos activated using cycloheximide and 6-dimethylaminopurine (DMAP) than in those activated using PLCZ or derived from IVF. These results demonstrate that exogenous PLCZ can be used to activate bovine SCNT-derived embryos and support the hypothesis that a fertilization-like activation response can enhance some aspects of nuclear reprogramming. PMID:19074500

  13. One-two step transfer observed in 16O+11B nuclear system

    NASA Astrophysics Data System (ADS)

    Hamada, Sh.; Burtebayev, N.

    2015-06-01

    The angular distribution measurements for 16O ion beam elastically scattered from 11B target of thickness 32.9μg/cm2 at energy 22.4 MeV had been performed in the cyclotron DC-60 INP NNC RK. The previous measurements for 16O+11B nuclear system at energies 27, 30, 32.5 and 35 MeV showed an increase in the differential cross-section at backward angles due to the contribution of cluster transfer. Such transfer process could not be described in terms of optical model (OM); it could be described within the framework of distorted wave Born approximation method implemented in FRESCO code. Both one (5Li) and two-step transfer (proton transfer followed by Alpha transfer) were taken into considerations. We have extracted the spectroscopic amplitude (SA) for the configuration 16O→11B+5Li.

  14. Passive heat-transfer means for nuclear reactors. [LMFBR

    DOEpatents

    Burelbach, J.P.

    1982-06-10

    An improved passive cooling arrangement is disclosed for maintaining adjacent or related components of a nuclear reactor within specified temperature differences. Specifically, heat pipes are operatively interposed between the components, with the vaporizing section of the heat pipe proximate the hot component operable to cool it and the primary condensing section of the heat pipe proximate the other and cooler component operable to heat it. Each heat pipe further has a secondary condensing section that is located outwardly beyond the reactor confinement and in a secondary heat sink, such as air ambient the containment, that is cooler than the other reactor component. By having many such heat pipes, an emergency passive cooling system is defined that is operative without electrical power.

  15. Quantum state transfer between an optomechanical cavity and a diamond nuclear spin ensemble

    NASA Astrophysics Data System (ADS)

    Feng, Zhi-Bo; Wang, Hong-Ling; Yan, Run-Ying

    2016-08-01

    We explore an efficient scheme for transferring quantum state between an optomechanical cavity and nuclear spins of nitrogen-vacancy centers in diamond, where quantum information can be efficiently stored (retrieved) into (from) the nuclear spin ensemble assisted by a mechanical resonator in a dispersive regime. Our scheme works for a broad range of cavity frequencies and might have potential applications in employing the nuclear spin ensemble as a memory in quantum information processing. The feasibility of our protocol is analyzed using currently available parameters.

  16. Quantum state transfer between an optomechanical cavity and a diamond nuclear spin ensemble

    NASA Astrophysics Data System (ADS)

    Feng, Zhi-Bo; Wang, Hong-Ling; Yan, Run-Ying

    2016-05-01

    We explore an efficient scheme for transferring quantum state between an optomechanical cavity and nuclear spins of nitrogen-vacancy centers in diamond, where quantum information can be efficiently stored (retrieved) into (from) the nuclear spin ensemble assisted by a mechanical resonator in a dispersive regime. Our scheme works for a broad range of cavity frequencies and might have potential applications in employing the nuclear spin ensemble as a memory in quantum information processing. The feasibility of our protocol is analyzed using currently available parameters.

  17. 78 FR 67925 - Transfer of Real Property at Defense Nuclear Facilities for Economic Development

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-13

    ... process it will follow in the development of such regulations (65 FR 13735). DOE has examined today's rule...-AA82 Transfer of Real Property at Defense Nuclear Facilities for Economic Development AGENCY... final rule published on February 29, 2000, 65 FR 10685, as final, with changes. The final...

  18. Nucleologenesis and embryonic genome activation are defective in interspecies cloned embryos between bovine ooplasm and rhesus monkey somatic cells

    PubMed Central

    Song, Bong-Seok; Lee, Sang-Hee; Kim, Sun-Uk; Kim, Ji-Su; Park, Jung Sun; Kim, Cheol-Hee; Chang, Kyu-Tae; Han, Yong-Mahn; Lee, Kyung-Kwang; Lee, Dong-Seok; Koo, Deog-Bon

    2009-01-01

    Background Interspecies somatic cell nuclear transfer (iSCNT) has been proposed as a tool to address basic developmental questions and to improve the feasibility of cell therapy. However, the low efficiency of iSCNT embryonic development is a crucial problem when compared to in vitro fertilization (IVF) and intraspecies SCNT. Thus, we examined the effect of donor cell species on the early development of SCNT embryos after reconstruction with bovine ooplasm. Results No apparent difference in cleavage rate was found among IVF, monkey-bovine (MB)-iSCNT, and bovine-bovine (BB)-SCNT embryos. However, MB-iSCNT embryos failed to develop beyond the 8- or 16-cell stages and lacked expression of the genes involved in embryonic genome activation (EGA) at the 8-cell stage. From ultrastructural observations made during the peri-EGA period using transmission electron microscopy (TEM), we found that the nucleoli of MB-iSCNT embryos were morphologically abnormal or arrested at the primary stage of nucleologenesis. Consistent with the TEM analysis, nucleolar component proteins, such as upstream binding transcription factor, fibrillarin, nucleolin, and nucleophosmin, showed decreased expression and were structurally disorganized in MB-iSCNT embryos compared to IVF and BB-SCNT embryos, as revealed by real-time PCR and immunofluorescence confocal laser scanning microscopy, respectively. Conclusion The down-regulation of housekeeping and imprinting genes, abnormal nucleolar morphology, and aberrant patterns of nucleolar proteins during EGA resulted in developmental failure in MB-iSCNT embryos. These results provide insight into the unresolved problems of early embryonic development in iSCNT embryos. PMID:19635167

  19. Tie Tube Heat Transfer Modeling for Bimodal Nuclear Thermal Rockets

    SciTech Connect

    Clough, Joshua A.; Starkey, Ryan P.; Lewis, Mark J.; Lavelle, Thomas M.

    2007-01-30

    Bimodal nuclear thermal rocket systems have been shown to reduce the weight and cost of space vehicles to Mars and beyond by utilizing the reactor for power generation in the relatively long duration between burns in an interplanetary trajectory. No information, however, is available regarding engine and reactor-level operation of such bimodal systems. The purpose of this project is to generate engine and reactor models with sufficient fidelity and flexibility to accurately study the component-level effects of operating a propulsion-designed reactor at power generation levels. Previous development of a 1-D reactor and tie tube model found that ignoring heat generation inside of the tie tube leads to under-prediction of the temperature change and over-prediction of pressure change across the tie tube. This paper will present the development and results of a tie tube model that has been extended to account for heat generation, specifically in the moderator layer. This model is based on a 1-D distribution of power in the fuel elements and tie tubes, as a precursor to an eventual neutron-driven reactor model.

  20. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false What procedures are to be used to transfer real property at defense nuclear facilities for economic development? 770.7 Section 770.7 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7...

  1. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May...

  2. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May...

  3. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May...

  4. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May...

  5. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May...

  6. Modularization and nuclear power. Report by the Technology Transfer Modularization Task Team

    SciTech Connect

    Not Available

    1985-06-01

    This report describes the results of the work performed by the Technology Transfer Task Team on Modularization. This work was performed as part of the Technology Transfer work being performed under Department of Energy Contract 54-7WM-335406, between December, 1984 and February, 1985. The purpose of this task team effort was to briefly survey the current use of modularization in the nuclear and non-nuclear industries and to assess and evaluate the techniques available for potential application to nuclear power. A key conclusion of the evaluation was that there was a need for a study to establish guidelines for the future development of Light Water Reactor, High Temperature Gas Reactor and Liquid Metal Reactor plants. The guidelines should identify how modularization can improve construction, maintenance, life extension and decommissioning.

  7. High-fidelity transfer and storage of photon states in a single nuclear spin

    NASA Astrophysics Data System (ADS)

    Yang, Sen; Wang, Ya; Rao, D. D. Bhaktavatsala; Hien Tran, Thai; Momenzadeh, Ali S.; Markham, M.; Twitchen, D. J.; Wang, Ping; Yang, Wen; Stöhr, Rainer; Neumann, Philipp; Kosaka, Hideo; Wrachtrup, Jörg

    2016-08-01

    Long-distance quantum communication requires photons and quantum nodes that comprise qubits for interaction with light and good memory capabilities, as well as processing qubits for the storage and manipulation of photons. Owing to the unavoidable photon losses, robust quantum communication over lossy transmission channels requires quantum repeater networks. A necessary and highly demanding prerequisite for these networks is the existence of quantum memories with long coherence times to reliably store the incident photon states. Here we demonstrate the high-fidelity (∼98%) coherent transfer of a photon polarization state to a single solid-state nuclear spin that has a coherence time of over 10 s. The storage process is achieved by coherently transferring the polarization state of a photon to an entangled electron–nuclear spin state of a nitrogen–vacancy centre in diamond. The nuclear spin-based optical quantum memory demonstrated here paves the way towards an absorption-based quantum repeater network.

  8. Explaining dehumanization among children: the interspecies model of prejudice.

    PubMed

    Costello, Kimberly; Hodson, Gordon

    2014-03-01

    Although many theoretical approaches have emerged to explain prejudices expressed by children, none incorporate outgroup dehumanization, a key predictor of prejudice among adults. According to the Interspecies Model of Prejudice, beliefs in the human-animal divide facilitate outgroup prejudice through fostering animalistic dehumanization (Costello & Hodson, 2010). In the present investigation, White children attributed Black children fewer 'uniquely human' characteristics, representing the first systematic evidence of racial dehumanization among children (Studies 1 and 2). In Study 2, path analyses supported the Interspecies Model of Prejudice: children's human-animal divide beliefs predicted greater racial prejudice, an effect explained by heightened racial dehumanization. Similar patterns emerged among parents. Furthermore, parent Social Dominance Orientation predicted child prejudice indirectly through children's endorsement of a hierarchical human-animal divide and subsequent dehumanizing tendencies. Encouragingly, children's human-animal divide perceptions were malleable to an experimental prime highlighting animal-human similarity. Implications for prejudice interventions are considered. PMID:23083220

  9. Critical issues in intra- and interspecies dosimetry of ozone

    SciTech Connect

    Miller, F.J.; Overton, J.H.

    1989-01-01

    Knowledge of dose at the target site is a fundamental starting point in making interspecies dosimetric comparisons. To the extent that information is available on the effective dose of a compound, the confidence in risk assessments is increased. To facilitate judgments about effects determined in animals relative to likelihood of risk associated with human exposure to ozone (O3), a mathematical dosimetry model has been developed for interspecies comparisons. The model incorporates the major factors affecting the absorption of O3 in the respiratory tract: the morphology of the respiratory tract, the route, depth and rate of breathing, physicochemical properties of O3, the physical and chemical processes which govern gas transport, and the physicochemical properties of the lining fluids and tissue material of the airways and gas exchange units. Also discussed are the application of the dosimetry model for examining age-dependent susceptibility to O3 and the potential usefulness of such models for relating microdosimetry to microtoxicology.

  10. Mammalian interspecies substitution of immune modulatory alleles by genome editing.

    PubMed

    Lillico, Simon G; Proudfoot, Chris; King, Tim J; Tan, Wenfang; Zhang, Lei; Mardjuki, Rachel; Paschon, David E; Rebar, Edward J; Urnov, Fyodor D; Mileham, Alan J; McLaren, David G; Whitelaw, C Bruce A

    2016-01-01

    We describe a fundamentally novel feat of animal genetic engineering: the precise and efficient substitution of an agronomic haplotype into a domesticated species. Zinc finger nuclease in-embryo editing of the RELA locus generated live born domestic pigs with the warthog RELA orthologue, associated with resilience to African Swine Fever. The ability to efficiently achieve interspecies allele introgression in one generation opens unprecedented opportunities for agriculture and basic research. PMID:26898342

  11. Mammalian interspecies substitution of immune modulatory alleles by genome editing

    PubMed Central

    Lillico, Simon G.; Proudfoot, Chris; King, Tim J.; Tan, Wenfang; Zhang, Lei; Mardjuki, Rachel; Paschon, David E.; Rebar, Edward J.; Urnov, Fyodor D.; Mileham, Alan J.; McLaren, David G.; Whitelaw, C. Bruce A.

    2016-01-01

    We describe a fundamentally novel feat of animal genetic engineering: the precise and efficient substitution of an agronomic haplotype into a domesticated species. Zinc finger nuclease in-embryo editing of the RELA locus generated live born domestic pigs with the warthog RELA orthologue, associated with resilience to African Swine Fever. The ability to efficiently achieve interspecies allele introgression in one generation opens unprecedented opportunities for agriculture and basic research. PMID:26898342

  12. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false What procedures are to be used to transfer real property... ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7 What... congressional defense committees through the Secretary of Energy. (d) Transfer. After the...

  13. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false What procedures are to be used to transfer real property... ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7 What... congressional defense committees through the Secretary of Energy. (d) Transfer. After the...

  14. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false What procedures are to be used to transfer real property... ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7 What... congressional defense committees through the Secretary of Energy. (d) Transfer. After the...

  15. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false What procedures are to be used to transfer real property... ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7 What... congressional defense committees through the Secretary of Energy. (d) Transfer. After the...

  16. Mechanisms Underlying Mammalian Hybrid Sterility in Two Feline Interspecies Models.

    PubMed

    Davis, Brian W; Seabury, Christopher M; Brashear, Wesley A; Li, Gang; Roelke-Parker, Melody; Murphy, William J

    2015-10-01

    The phenomenon of male sterility in interspecies hybrids has been observed for over a century, however, few genes influencing this recurrent phenotype have been identified. Genetic investigations have been primarily limited to a small number of model organisms, thus limiting our understanding of the underlying molecular basis of this well-documented "rule of speciation." We utilized two interspecies hybrid cat breeds in a genome-wide association study employing the Illumina 63 K single-nucleotide polymorphism array. Collectively, we identified eight autosomal genes/gene regions underlying associations with hybrid male sterility (HMS) involved in the function of the blood-testis barrier, gamete structural development, and transcriptional regulation. We also identified several candidate hybrid sterility regions on the X chromosome, with most residing in close proximity to complex duplicated regions. Differential gene expression analyses revealed significant chromosome-wide upregulation of X chromosome transcripts in testes of sterile hybrids, which were enriched for genes involved in chromatin regulation of gene expression. Our expression results parallel those reported in Mus hybrids, supporting the "Large X-Effect" in mammalian HMS and the potential epigenetic basis for this phenomenon. These results support the value of the interspecies feline model as a powerful tool for comparison to rodent models of HMS, demonstrating unique aspects and potential commonalities that underpin mammalian reproductive isolation. PMID:26006188

  17. Intra- and inter-species spread of carbapenemase genes in a non-hospitalized patient.

    PubMed

    Sorlí, L; Miró, E; Segura, C; Navarro, F; Grau, S; Salvado, M; Horcajada, J P

    2011-12-01

    The purpose of this study was to report intra- and inter-species spread of carbapenemase genes between gram negative rods isolated from a non-hospitalized patient with bacteremia. The approach included chart review, antibiotic susceptibility testing and phenotypic screening for metallo-β-lactamase (MBL) detection, PCR and sequencing of bla, aac(6')-Ib and qnr genes, and plasmid analysis by PCR-based replicon typing. The clonal relationships between the isolates were analysed by comparing PFGE profiles. A non-hospitalized patient presented bacteraemia due to wild type Enterobacter cloacae (4.08), a VIM-1-producing E. cloacae (5.08), a VIM-1- and CTX-M-9-producing E. cloacae (7.08), a VIM-2-producing Pseudomonas aeruginosa, and catheter colonization by VIM-1-producing Klebsiella oxytoca. The patient had no previous hospitalization but had recently undergone an ambulatory colonoscopy. In E. cloacae 7.08 and K. oxytoca isolates, the bla(VIM-1) gene was located on a transferable plasmid of 48.5 kb, while in E. cloacae 5.08 the bla(VIM-1) gene was encoded on a 194 kb non-transferable plasmid. The bla(CTX-M-9) gene detected in E. cloacae was encoded on an HI2 plasmid of 290 kb. To date the prevalence of VIM-1 enzymes in the community is low. This molecular finding suggests an intra-species and/or inter-species horizontal spread of the MBL gene in the same non-hospitalized patient. PMID:21491175

  18. Control of interspecies electron flow during anaerobic digestion: role of floc formation in syntrophic methanogenesis

    SciTech Connect

    Thiele, J.H.; Chartrain, M.; Zeikus, J.G.

    1988-01-01

    The flora of an anaerobic whey-processing chemostat was separated by anaerobic sedimentation techniques into a free-living bacterial fraction and a bacterial floc fraction. The floc fraction constituted a major part (i.e., 57% total protein) of the total microbial population in the digestor, and it accounted for 87% of the total CO/sub 2/-dependent methanogenic activity and 76% of the total ethanol-consuming acetogenic activity. Lactose was degraded by both cellular fractions, but in the free flora fraction it was associated with higher intermediary levels of H/sub 2/, ethanol, butyrate, and propionate production. Electron microscopic analysis of flocs showed bacterial diversity and juxtapositioning of tentative Desulfovibrio and Methanobacterium species without significant microcolony formation. Ethanol, an intermediary product of lactose-hydrolyzing bacteria, was converted to acetate and methane within the flocs by interspecies electron transfer. Ethanol-dependent methane formation was compartmentalized and closely coupled kinetically within the flocs but without significant formation of H/sub 2/ gas. Physical disruption of flocs into fragments of 10- to 20-..mu..m diameter initially increased the H/sub 2/ partial pressure but did not change the carbon transformation kinetic patterns of ethanol metabolism or demonstrate a significant role for H/sub 2/ in CO/sub 2/ reduction to methane. The data demonstrate that floc formation in a whey-processing anaerobic digestor functions in juxtapositioning cells for interspecies electron transfer during syntrophic ethanol conversion into acetate and methane but by a mechanism which was independent of the available dissolved H/sub 2/ gas pool in the ecosystem.

  19. Molecular and biological aspects of early germ cell development in interspecies hybrids between chickens and pheasants.

    PubMed

    Kang, Seok Jin; Sohn, Sea Hwan; Kang, Kyung Soo; Lee, Hyung Chul; Lee, Seul Ki; Choi, Jin Won; Han, Jae Yong

    2011-03-01

    Interspecific hybrids provide insights into fundamental genetic principles, and may prove useful for biotechnological applications and as tools for the conservation of endangered species. In the present study, interspecies hybrids were generated between the Korean ring-necked pheasant (Phasianus colchicus) and the White Leghorn chicken (Gallus gallus domesticus). We determined whether these hybrids were good recipients for the production of germline chimeric birds. PCR-based species-specific amplification and karyotype analyses showed that the hybrids inherited genetic material from both parents. Evaluation of biological function indicated that the growth rates of hybrids during the exponential phase (body weight/week) were similar to those of the pheasant but not the chicken, and that the incubation period for hatching was significantly different from that of both parents. Primordial germ cells (PGCs) of hybrids reacted with a pheasant PGC-specific antibody and circulated normally in blood vessels. The peak time of hybrid PGC migration was equivalent to that of the pheasant. In late embryonic stages, germ cells were detected by the QCR1 antibody on 15 d male gonads and were normally localized in the seminiferous cords. We examined the migration ability and developmental localization of exogenous PGCs transferred into the blood vessels of 63 h hybrid embryos. Donor-derived PGCs reacted with a donor-specific antibody were detected on 7 d gonads and the seminiferous tubules of hatchlings. Therefore, germ cell transfer into developing embryos of an interspecies hybrid can be efficiently used for the conservation of threatened animals and endangered species, and many biotechnological applications. PMID:21111472

  20. Significant improvement of mouse cloning technique by treatment with trichostatin A after somatic nuclear transfer

    SciTech Connect

    Kishigami, Satoshi . E-mail: kishigami@cdb.riken.jp; Mizutani, Eiji; Ohta, Hiroshi; Hikichi, Takafusa; Thuan, Nguyen Van; Wakayama, Sayaka; Bui, Hong-Thuy; Wakayama, Teruhiko

    2006-02-03

    The low success rate of animal cloning by somatic cell nuclear transfer (SCNT) is believed to be associated with epigenetic errors including abnormal DNA hypermethylation. Recently, we elucidated by using round spermatids that, after nuclear transfer, treatment of zygotes with trichostatin A (TSA), an inhibitor of histone deacetylase, can remarkably reduce abnormal DNA hypermethylation depending on the origins of transferred nuclei and their genomic regions [S. Kishigami, N. Van Thuan, T. Hikichi, H. Ohta, S. Wakayama. E. Mizutani, T. Wakayama, Epigenetic abnormalities of the mouse paternal zygotic genome associated with microinsemination of round spermatids, Dev. Biol. (2005) in press]. Here, we found that 5-50 nM TSA-treatment for 10 h following oocyte activation resulted in more efficient in vitro development of somatic cloned embryos to the blastocyst stage from 2- to 5-fold depending on the donor cells including tail tip cells, spleen cells, neural stem cells, and cumulus cells. This TSA-treatment also led to more than 5-fold increase in success rate of mouse cloning from cumulus cells without obvious abnormality but failed to improve ES cloning success. Further, we succeeded in establishment of nuclear transfer-embryonic stem (NT-ES) cells from TSA-treated cloned blastocyst at a rate three times higher than those from untreated cloned blastocysts. Thus, our data indicate that TSA-treatment after SCNT in mice can dramatically improve the practical application of current cloning techniques.

  1. Cytoskeletal to Nuclear Strain Transfer Regulates YAP Signaling in Mesenchymal Stem Cells

    PubMed Central

    Driscoll, Tristan P.; Cosgrove, Brian D.; Heo, Su-Jin; Shurden, Zach E.; Mauck, Robert L.

    2015-01-01

    Mechanical forces transduced to cells through the extracellular matrix are critical regulators of tissue development, growth, and homeostasis, and can play important roles in directing stem cell differentiation. In addition to force-sensing mechanisms that reside at the cell surface, there is growing evidence that forces transmitted through the cytoskeleton and to the nuclear envelope are important for mechanosensing, including activation of the Yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding motif (TAZ) pathway. Moreover, nuclear shape, mechanics, and deformability change with differentiation state and have been likewise implicated in force sensing and differentiation. However, the significance of force transfer to the nucleus through the mechanosensing cytoskeletal machinery in the regulation of mesenchymal stem cell mechanobiologic response remains unclear. Here we report that actomyosin-generated cytoskeletal tension regulates nuclear shape and force transmission through the cytoskeleton and demonstrate the differential short- and long-term response of mesenchymal stem cells to dynamic tensile loading based on the contractility state, the patency of the actin cytoskeleton, and the connections it makes with the nucleus. Specifically, we show that while some mechanoactive signaling pathways (e.g., ERK signaling) can be activated in the absence of nuclear strain transfer, cytoskeletal strain transfer to the nucleus is essential for activation of the YAP/TAZ pathway with stretch. PMID:26083918

  2. Polarization Transfer from Ligands Hyperpolarized by Dissolution Dynamic Nuclear Polarization for Screening in Drug Discovery.

    PubMed

    Min, Hlaing; Sekar, Giridhar; Hilty, Christian

    2015-09-01

    Nuclear magnetic resonance (NMR) spectroscopy is a valuable technique for ligand screening, because it exhibits high specificity toward chemical structure and interactions. Dissolution dynamic nuclear polarization (DNP) is a recent advance in NMR methodology that enables the creation of non-equilibrium spin states, which can dramatically increase NMR sensitivity. Here, the transfer of such spin polarization from hyperpolarized ligand to protein is observed. Mixing hyperpolarized benzamidine with the serine protease trypsin, a "fingerprint" of enhanced protein signals is observed, which shows a different intensity profile than the equilibrium NMR spectrum of the protein, but coincides closely to the frequency profile of a saturation transfer difference (STD) NMR experiment. The DNP experiment benefits from hyperpolarization and enables observation of all frequencies in a single, rapid experiment. Based on these merits, it is an interesting alternative to the widely used STD experiment for identification of protein-ligand interactions. PMID:26315550

  3. Ion engine propelled Earth-Mars cycler with nuclear thermal propelled transfer vehicle, volume 2

    NASA Technical Reports Server (NTRS)

    Meyer, Rudolf X.; Baker, Myles; Melko, Joseph

    1994-01-01

    The goal of this project was to perform a preliminary design of a long term, reusable transportation system between earth and Mars which would be capable of providing both artificial gravity and shelter from solar flare radiation. The heart of this system was assumed to be a Cycler spacecraft propelled by an ion propulsion system. The crew transfer vehicle was designed to be propelled by a nuclear-thermal propulsion system. Several Mars transportation system architectures and their associated space vehicles were designed.

  4. Neutron Transfer Reactions: Surrogates for Neutron Capture for Basic and Applied Nuclear Science

    SciTech Connect

    Cizewski, J. A.; Peters, W. A.; Allen, J.; Hatarik, R.; Matthews, C.; O'Malley, P.; Jones, K. L.; Kozub, R. L.; Howard, J.; Patterson, N.; Paulauskas, S. V.; Rogers, J.; Sissom, D. J.; Pain, S. D.; Adekola, A.; Bardayan, D. W.; Blackmon, J. C.; Liang, F.; Nesaraja, C. D.; Pittman, S. T.

    2009-03-10

    Neutron capture reactions on unstable nuclei are important for both basic and applied nuclear science. A program has been developed at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory to study single-neutron transfer (d,p) reactions with rare isotope beams to provide information on neutron-induced reactions on unstable nuclei. Results from (d,p) studies on {sup 130,132}Sn, {sup 134}Te and {sup 75}As are discussed.

  5. Neutron transfer reactions: Surrogates for neutron capture for basic and applied nuclear science

    SciTech Connect

    Cizewski, J. A.; Jones, K. L.; Kozub, R. L.; Pain, Steven D; Peters, W. A.; Adekola, Aderemi S; Allen, J.; Bardayan, Daniel W; Becker, J.; Blackmon, Jeff C; Chae, K. Y.; Chipps, K.; Erikson, Luke; Gaddis, A. L.; Harlin, Christopher W; Hatarik, Robert; Howard, Joshua A; Jandel, M.; Johnson, Micah; Kapler, R.; Krolas, W.; Liang, J Felix; Livesay, Jake; Ma, Zhanwen; Matei, Catalin; Matthews, C.; Moazen, Brian; Nesaraja, Caroline D; O'Malley, Patrick; Patterson, N. P.; Paulauskas, Stanley; Pelham, T.; Pittman, S. T.; Radford, David C; Rogers, J.; Schmitt, Kyle; Shapira, Dan; ShrinerJr., J. F.; Sissom, D. J.; Smith, Michael Scott; Swan, T. P.; Thomas, J. S.; Vieira, D. J.; Wilhelmy, J. B.; Wilson, Gemma L

    2009-04-01

    Neutron capture reactions on unstable nuclei are important for both basic and applied nuclear science. A program has been developed at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory to study single-neutron transfer (d,p) reactions with rare isotope beams to provide information on neutron-induced reactions on unstable nuclei. Results from (d,p) studies on {sup 130,132}Sn, {sup 134}Te and {sup 75}As are discussed.

  6. An inter-subspecies cloned buffalo (Bubalus bubalis) obtained by transferring of cryopreserved embryos via somatic cell nuclear transfer.

    PubMed

    Yang, B Z; Yang, C Y; Li, R C; Qin, G S; Zhang, X F; Pang, C Y; Chen, M T; Huang, F X; Li, Z; Zheng, H Y; Huang, Y J; Liang, X W

    2010-10-01

    The aim of this study was to explore the feasibility of cryopreservation of inter-subspecies cloned embryos in buffalo. In our experiment, river buffalo ear fibroblast nucleus was fused into swamp buffalo oocyte cytoplasm. The blastocyst formation rate for nuclear transfer of freshly thawed cells was not different from those of growing cells, confluent or serum-starved cells. A total of 122 cloned blastocysts derived from cryopreserved fibroblasts were cryopreserved and thawed, 37 were survived, the cryosurvival rate was 30.3%. The survived blastocysts were transferred into 15 recipient buffalos. Five of the recipients established pregnancy, but four of them aborted on day 53, 59, 145 and 179 of gestation respectively. One cross-bred buffalo (Murrah × Swamp buffalo (2n = 49) received three embryos delivered a 40.5 kg female calf by natural delivery on day 320 of gestation. Up to now (13-month old), the cloned calf has been growing well with no abnormity observed. These results demonstrated that cryopreservation of inter-subspecies cloned embryos is feasible to produce buffalo offspring. PMID:19788521

  7. Production of human CD59-transgenic pigs by embryonic germ cell nuclear transfer

    SciTech Connect

    Ahn, Kwang Sung; Won, Ji Young; Park, Jin-Ki; Sorrell, Alice M.; Heo, Soon Young; Kang, Jee Hyun; Woo, Jae-Seok; Choi, Bong-Hwan; Chang, Won-Kyong; Shim, Hosup

    2010-10-01

    Research highlights: {yields} Human CD59 (hCD59) gene was introduced into porcine embryonic germ (EG) cells. {yields} hCD59-transgenic EG cells were resistant to hyperacute rejection in cytolytic assay. {yields} hCD59-transgenic pigs were produced by EG cell nuclear transfer. -- Abstract: This study was performed to produce transgenic pigs expressing the human complement regulatory protein CD59 (hCD59) using the nuclear transfer (NT) of embryonic germ (EG) cells, which are undifferentiated stem cells derived from primordial germ cells. Because EG cells can be cultured indefinitely in an undifferentiated state, they may provide an inexhaustible source of nuclear donor cells for NT to produce transgenic pigs. A total of 1980 NT embryos derived from hCD59-transgenic EG cells were transferred to ten recipients, resulting in the birth of fifteen piglets from three pregnancies. Among these offspring, ten were alive without overt health problems. Based on PCR analysis, all fifteen piglets were confirmed as hCD59 transgenic. The expression of the hCD59 transgene in the ten living piglets was verified by RT-PCR. Western analysis showed the expression of the hCD59 protein in four of the ten RT-PCR-positive piglets. These results demonstrate that hCD59-transgenic pigs could effectively be produced by EG cell NT and that such transgenic pigs may be used as organ donors in pig-to-human xenotransplantation.

  8. Reprogramming within hours following nuclear transfer into mouse but not human zygotes.

    PubMed

    Egli, Dieter; Chen, Alice E; Saphier, Genevieve; Ichida, Justin; Fitzgerald, Claire; Go, Kathryn J; Acevedo, Nicole; Patel, Jay; Baetscher, Manfred; Kearns, William G; Goland, Robin; Leibel, Rudolph L; Melton, Douglas A; Eggan, Kevin

    2011-01-01

    Fertilized mouse zygotes can reprogram somatic cells to a pluripotent state. Human zygotes might therefore be useful for producing patient-derived pluripotent stem cells. However, logistical, legal and social considerations have limited the availability of human eggs for research. Here we show that a significant number of normal fertilized eggs (zygotes) can be obtained for reprogramming studies. Using these zygotes, we found that when the zygotic genome was replaced with that of a somatic cell, development progressed normally throughout the cleavage stages, but then arrested before the morula stage. This arrest was associated with a failure to activate transcription in the transferred somatic genome. In contrast to human zygotes, mouse zygotes reprogrammed the somatic cell genome to a pluripotent state within hours after transfer. Our results suggest that there may be a previously unappreciated barrier to successful human nuclear transfer, and that future studies could focus on the requirements for genome activation. PMID:21971503

  9. PRESTO polarization transfer to quadrupolar nuclei: implications for dynamic nuclear polarization.

    PubMed

    Perras, Frédéric A; Kobayashi, Takeshi; Pruski, Marek

    2015-09-21

    We show both experimentally and numerically on a series of model systems that in experiments involving transfer of magnetization from (1)H to the quadrupolar nuclei under magic-angle-spinning (MAS), the PRESTO technique consistently outperforms traditionally used cross polarization (CP), affording more quantitative intensities, improved lineshapes, better overall sensitivity, and straightforward optimization. This advantage derives from the fact that PRESTO circumvents the convoluted and uncooperative spin dynamics during the CP transfer under MAS, by replacing the spin-locking of quadrupolar nuclei with a single central transition selective 90° pulse and using a symmetry-based recoupling sequence in the (1)H channel. This is of particular importance in the context of dynamic nuclear polarization (DNP) NMR of quadrupolar nuclei, where the efficient transfer of enhanced (1)H polarization is desired to obtain the highest sensitivity. PMID:26266874

  10. Nonideal rotations in nuclear magnetic resonance: Estimation of coherence transfer leakage

    SciTech Connect

    Jerschow, Alexej

    2000-07-15

    When spherical tensors are rotated by certain angles, coherence transfer selection rules may apply. For example, a {pi} rotation cleanly inverts the coherence order. A {pi}/2 rotation of a T{sub 0}{sup 1} tensor creates only T{sub {+-}}{sub 1}{sup 1} tensors. In this work estimations are given for the coherence transfer leakage under the action of rotations with small errors in the rotation angle or axis. Although the theory is stated with particular applications to NMR (nuclear magnetic resonance) in mind it is equally applicable wherever nonideal rotations of spherical tensors are considered (e.g., quantum computing and relaxation theory). In NMR it is useful for the estimation of coherence transfer leakage, especially in pulse sequences with many n{pi} pulses. The results are also applicable to spinors and half-integer representations of the rotation group. (c) 2000 American Institute of Physics.

  11. PRESTO polarization transfer to quadrupolar nuclei: Implications for dynamic nuclear polarization

    DOE PAGESBeta

    Perras, Frederic A.; Kobayashi, Takeshi; Pruski, Marek

    2015-08-04

    In this study, we show both experimentally and numerically on a series of model systems that in experiments involving transfer of magnetization from 1H to the quadrupolar nuclei under magic-angle-spinning (MAS), the PRESTO technique consistently outperforms traditionally used cross polarization (CP), affording more quantitative intensities, improved lineshapes, better overall sensitivity, and straightforward optimization. This advantage derives from the fact that PRESTO circumvents the convoluted and uncooperative spin dynamics during the CP transfer under MAS, by replacing the spin-locking of quadrupolar nuclei with a single central transition selective 90° pulse and using a symmetry-based recoupling sequence in the 1H channel. Thismore » is important in the context of dynamic nuclear polarization (DNP) NMR of quadrupolar nuclei, where the efficient transfer of enhanced 1H polarization is desired to obtain the highest sensitivity.« less

  12. PRESTO polarization transfer to quadrupolar nuclei: Implications for dynamic nuclear polarization

    SciTech Connect

    Perras, Frederic A.; Kobayashi, Takeshi; Pruski, Marek

    2015-08-04

    In this study, we show both experimentally and numerically on a series of model systems that in experiments involving transfer of magnetization from 1H to the quadrupolar nuclei under magic-angle-spinning (MAS), the PRESTO technique consistently outperforms traditionally used cross polarization (CP), affording more quantitative intensities, improved lineshapes, better overall sensitivity, and straightforward optimization. This advantage derives from the fact that PRESTO circumvents the convoluted and uncooperative spin dynamics during the CP transfer under MAS, by replacing the spin-locking of quadrupolar nuclei with a single central transition selective 90° pulse and using a symmetry-based recoupling sequence in the 1H channel. This is important in the context of dynamic nuclear polarization (DNP) NMR of quadrupolar nuclei, where the efficient transfer of enhanced 1H polarization is desired to obtain the highest sensitivity.

  13. Artificial intelligence and nuclear power. Report by the Technology Transfer Artificial Intelligence Task Team

    SciTech Connect

    Not Available

    1985-06-01

    The Artificial Intelligence Task Team was organized to review the status of Artificial Intelligence (AI) technology, identify guidelines for AI work, and to identify work required to allow the nuclear industry to realize maximum benefit from this technology. The state of the nuclear industry was analyzed to determine where the application of AI technology could be of greatest benefit. Guidelines and criteria were established to focus on those particular problem areas where AI could provide the highest possible payoff to the industry. Information was collected from government, academic, and private organizations. Very little AI work is now being done to specifically support the nuclear industry. The AI Task Team determined that the establishment of a Strategic Automation Initiative (SAI) and the expansion of the DOE Technology Transfer program would ensure that AI technology could be used to develop software for the nuclear industry that would have substantial financial payoff to the industry. The SAI includes both long and short term phases. The short-term phase includes projects which would demonstrate that AI can be applied to the nuclear industry safely, and with substantial financial benefit. The long term phase includes projects which would develop AI technologies with specific applicability to the nuclear industry that would not be developed by people working in any other industry.

  14. Rabbit embryonic stem cell lines derived from fertilized, parthenogenetic or somatic cell nuclear transfer embryos

    SciTech Connect

    Fang, Zhen F.; Gai, Hui; Huang, You Z.; Li, Shan G.; Chen, Xue J.; Shi, Jian J.; Wu, Li; Liu, Ailian; Xu, Ping; Sheng, Hui Z. . E-mail: hzsheng2003@yahoo.com

    2006-11-01

    Embryonic stem cells were isolated from rabbit blastocysts derived from fertilization (conventional rbES cells), parthenogenesis (pES cells) and nuclear transfer (ntES cells), and propagated in a serum-free culture system. Rabbit ES (rbES) cells proliferated for a prolonged time in an undifferentiated state and maintained a normal karyotype. These cells grew in a monolayer with a high nuclear/cytoplasm ratio and contained a high level of alkaline phosphate activity. In addition, rbES cells expressed the pluripotent marker Oct-4, as well as EBAF2, FGF4, TDGF1, but not antigens recognized by antibodies against SSEA-1, SSEA-3, SSEA-4, TRA-1-10 and TRA-1-81. All 3 types of ES cells formed embryoid bodies and generated teratoma that contained tissue types of all three germ layers. rbES cells exhibited a high cloning efficiency, were genetically modified readily and were used as nuclear donors to generate a viable rabbit through somatic cell nuclear transfer. In combination with genetic engineering, the ES cell technology should facilitate the creation of new rabbit lines.

  15. Widespread interspecies homologous recombination reveals reticulate evolution within the genus Streptomyces.

    PubMed

    Cheng, Kun; Rong, Xiaoying; Huang, Ying

    2016-09-01

    Homologous recombination is increasingly being recognized as a driving force in microbial evolution. However, recombination in streptomycetes, a rich source of diverse secondary metabolites, particularly among different species, remains minimally investigated. In this study, the largest sample of Streptomyces species to date, consisting of 142 type strains spanning the genus, with available sequences of 16S rRNA, atpD, gyrB, recA, rpoB and trpB genes, were collected and subjected to a comprehensive population genetic analysis to generate an overall estimate of the level of Streptomyces interspecies genetic exchange and its effect on the evolution of this genus. The results indicate frequent homologous recombination among Streptomyces species, which occurred three times more frequently and was nearly 14 times more important than point mutation in nucleotide sequence divergence (ρ/θw=3.10, r/m=13.74). As a result, a facilitating effect on the evolutionary process and confusion in phylogenetic relationships were observed, as well as a number of specific transfer events of the six gene fragments. A resultant phylogenetic network depicted extensive horizontal genetic exchange which decays clonality in streptomycetes. Moreover, seven evolutionary lineage groups were identified in the present sample in the Structure analysis, generally consistent with morphological and physiological data, and the contribution of recombination was detected to be varied among them. Our analyses demonstrated a reticulate evolution within Streptomyces due to the high level of interspecies gene exchange, which greatly challenges the traditional tree-shaped phylogeny in this genus and may advance our evolutionary understanding of a genuine Streptomyces species. PMID:27329941

  16. Coherent transfer of nuclear spin polarization in field-cycling NMR experiments

    SciTech Connect

    Pravdivtsev, Andrey N.; Yurkovskaya, Alexandra V.; Ivanov, Konstantin L.; Vieth, Hans-Martin

    2013-12-28

    Coherent polarization transfer effects in a coupled spin network have been studied over a wide field range. The transfer mechanism is based on exciting zero-quantum coherences between the nuclear spin states by means of non-adiabatic field jump from high to low magnetic field. Subsequent evolution of these coherences enables conversion of spin order in the system, which is monitored after field jump back to high field. Such processes are most efficient when the spin system passes through an avoided level crossing during the field variation. The polarization transfer effects have been demonstrated for N-acetyl histidine, which has five scalar coupled protons; the initial spin order has been prepared by applying RF-pulses at high magnetic field. The observed oscillatory transfer kinetics is taken as a clear indication of a coherent mechanism; level crossing effects have also been demonstrated. The experimental data are in very good agreement with the theoretical model of coherent polarization transfer. The method suggested is also valid for other types of initial polarization in the spin system, most notably, for spin hyperpolarization.

  17. Technological requirements of nuclear electric propulsion systems for fast Earth-Mars transfers

    NASA Astrophysics Data System (ADS)

    Bérend, N.; Epenoy, R.; Cliquet, E.; Laurent-Varin, J.; Avril, S.

    2013-03-01

    Recent advances in electric propulsion technologies such as magnetoplasma rockets gave a new momentum to the study of nuclear electric propulsion concepts for Mars missions. Some recent works have been focused on very short Earth-to-Mars transfers of about 40 days with high-power, variable specific impulse propulsion systems [1]. While the interest of nuclear electric propulsion appears clearly with regard to the payload mass ratio (due to a high level of specific impulse), its interest with regard to the transfer time is more complex to define, as it depends on many design parameters. In this paper, a general analysis of the capability of nuclear electric propulsion systems considering both criteria (the payload mass ratio and the transfer time) is performed, and the technological requirements for fast Earth-Mars transfers are studied. This analysis has been performed in two steps. First, complete trajectory optimizations have been performed by CNES-DCT in order to obtain the propulsion requirements of the mission for different technological hypotheses regarding the engine technology (specific impulse levels and the throttling capability) and different mission requirements. The methodology used for designing fuel-optimal heliocentric trajectories, based on the Pontryagin's Maximum Principle will be presented. Trajectories have been computed for various power levels combined with either variable or fixed Isp. The second step consisted in evaluating a simpler method that could easily link the main mission requirements (the transfer time and the payload fraction) to the main technological requirements (the specific mass of the power generation system and the structure mass ratio of the whole vehicle, excluding the power generation system). Indeed, for power-limited systems, propulsion requirements can be characterized through the "trajectory characteristic" parameter, defined as the integral over time of the squared thrust acceleration. Technological requirements for

  18. Production of Cloned Korean Native Pig by Somatic Cell Nuclear Transfer.

    PubMed

    Hwang, In-Sul; Kwon, Dae-Jin; Oh, Keun Bong; Ock, Sun-A; Chung, Hak-Jae; Cho, In-Cheol; Lee, Jeong-Woong; Im, Gi-Sun; Hwang, Seongsoo

    2015-06-01

    The Korean native pig (KNP) have been considered as animal models for animal biotechnology research because of their relatively small body size and their presumably highly inbred status due to the closed breeding program. However, little is reported about the use of KNP for animal biotechnology researches. This study was performed to establish the somatic cell nuclear transfer (SCNT) protocol for the production of swine leukocyte antigens (SLA) homotype-defined SCNT KNP. The ear fibroblast cells originated from KNP were cultured and used as donor cell. After thawing, the donor cells were cultured for 1 hour with 15 μM roscovitine prior to the nuclear transfer. The numbers of reconstructed and parthenogenetic embryos transferred were 98 ± 35.2 and 145 ± 11.2, respectively. The pregnancy and delivery rate were 3/5 (60%) and 2/5 (40%). One healthy SLA homotype-defined SCNT KNP was successfully generated. The recipient-based individual cloning efficiency ranged from 0.65 to 1.08%. Taken together, it can be postulated that the methodological establishment of the production of SLA homotype-defined cloned KNP can be applied to the generation of transgenic cloned KNP as model animals for human disease and xenotransplantation researches. PMID:27004264

  19. Establishment of an efficient somatic cell nuclear transfer system for production of transgenic pigs.

    PubMed

    Vajta, G; Callesen, H

    2012-04-15

    Handmade cloning (HMC) is now an established procedure used in several species for somatic cell nuclear transfer, but only applied in two related laboratories for pigs. The aim of this review is to facilitate widespread application by summarizing the process of establishment and explaining the background of the incorporated special approaches. Optimized steps of traditional cloning in pigs (in vitro maturation, activation, embryo culture) were merged with those of the micromanipulation-free HMC that has been modified according to the specific needs of sensitive porcine oocytes (partial zona digestion before enucleation, two-step zona-free fusion with the somatic cell; initiation of activation with the second fusion). The zona-free approach required embryo culture to the blastocyst stage before surgical transfer of embryos to the uterine horns of recipient sows in the proper phase of an unstimulated cycle. Eventually a competitive, inexpensive and reliable alternative to traditional porcine nuclear transfer cloning techniques evolved that is also suitable to produce transgenic offspring containing various genetic modifications to establish models for several human diseases with genetic background. Further improvements and involvement of additional techniques to increase the overall efficiency and facilitate practical applications are expected in the foreseeable future. PMID:22284219

  20. Production of Cloned Korean Native Pig by Somatic Cell Nuclear Transfer

    PubMed Central

    Hwang, In-Sul; Kwon, Dae-Jin; Oh, Keun Bong; Ock, Sun-A; Chung, Hak-Jae; Cho, In-Cheol; Lee, Jeong-Woong; Im, Gi-Sun; Hwang, Seongsoo

    2015-01-01

    The Korean native pig (KNP) have been considered as animal models for animal biotechnology research because of their relatively small body size and their presumably highly inbred status due to the closed breeding program. However, little is reported about the use of KNP for animal biotechnology researches. This study was performed to establish the somatic cell nuclear transfer (SCNT) protocol for the production of swine leukocyte antigens (SLA) homotype-defined SCNT KNP. The ear fibroblast cells originated from KNP were cultured and used as donor cell. After thawing, the donor cells were cultured for 1 hour with 15 μM roscovitine prior to the nuclear transfer. The numbers of reconstructed and parthenogenetic embryos transferred were 98 ± 35.2 and 145 ± 11.2, respectively. The pregnancy and delivery rate were 3/5 (60%) and 2/5 (40%). One healthy SLA homotype-defined SCNT KNP was successfully generated. The recipient-based individual cloning efficiency ranged from 0.65 to 1.08%. Taken together, it can be postulated that the methodological establishment of the production of SLA homotype-defined cloned KNP can be applied to the generation of transgenic cloned KNP as model animals for human disease and xenotransplantation researches. PMID:27004264

  1. Identification of Nuclear Effects in Neutrino-Carbon Interactions at Low Three-Momentum Transfer

    NASA Astrophysics Data System (ADS)

    Rodrigues, P. A.; Demgen, J.; Miltenberger, E.; Aliaga, L.; Altinok, O.; Bellantoni, L.; Bercellie, A.; Betancourt, M.; Bodek, A.; Bravar, A.; Budd, H.; Cai, T.; Carneiro, M. F.; Chvojka, J.; Devan, J.; Dytman, S. A.; Díaz, G. A.; Eberly, B.; Elkins, M.; Felix, J.; Fields, L.; Fine, R.; Gago, A. M.; Galindo, R.; Gallagher, H.; Ghosh, A.; Golan, T.; Gran, R.; Harris, D. A.; Higuera, A.; Hurtado, K.; Kiveni, M.; Kleykamp, J.; Kordosky, M.; Le, T.; Leistico, J. R.; Lovlein, A.; Maher, E.; Manly, S.; Mann, W. A.; Marshall, C. M.; Martinez Caicedo, D. A.; McFarland, K. S.; McGivern, C. L.; McGowan, A. M.; Messerly, B.; Miller, J.; Mislivec, A.; Morfín, J. G.; Mousseau, J.; Muhlbeier, T.; Naples, D.; Nelson, J. K.; Norrick, A.; Nuruzzaman; Osta, J.; Paolone, V.; Patrick, C. E.; Perdue, G. N.; Ramirez, M. A.; Ransome, R. D.; Ray, H.; Ren, L.; Rimal, D.; Ruterbories, D.; Schellman, H.; Schmitz, D. W.; Solano Salinas, C. J.; Tagg, N.; Tice, B. G.; Valencia, E.; Walton, T.; Wolcott, J.; Wospakrik, M.; Zavala, G.; Zhang, D.; Minerva Collaboration

    2016-02-01

    Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current νμ interactions is combined with muon kinematics to permit separation of the quasielastic and Δ (1232 ) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and Δ resonance processes are needed to describe the data. The data in this kinematic region also have an enhanced population of multiproton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments.

  2. Identification of Nuclear Effects in Neutrino-Carbon Interactions at Low Three-Momentum Transfer.

    PubMed

    Rodrigues, P A; Demgen, J; Miltenberger, E; Aliaga, L; Altinok, O; Bellantoni, L; Bercellie, A; Betancourt, M; Bodek, A; Bravar, A; Budd, H; Cai, T; Carneiro, M F; Chvojka, J; Devan, J; Dytman, S A; Díaz, G A; Eberly, B; Elkins, M; Felix, J; Fields, L; Fine, R; Gago, A M; Galindo, R; Gallagher, H; Ghosh, A; Golan, T; Gran, R; Harris, D A; Higuera, A; Hurtado, K; Kiveni, M; Kleykamp, J; Kordosky, M; Le, T; Leistico, J R; Lovlein, A; Maher, E; Manly, S; Mann, W A; Marshall, C M; Martinez Caicedo, D A; McFarland, K S; McGivern, C L; McGowan, A M; Messerly, B; Miller, J; Mislivec, A; Morfín, J G; Mousseau, J; Muhlbeier, T; Naples, D; Nelson, J K; Norrick, A; Nuruzzaman; Osta, J; Paolone, V; Patrick, C E; Perdue, G N; Ramirez, M A; Ransome, R D; Ray, H; Ren, L; Rimal, D; Ruterbories, D; Schellman, H; Schmitz, D W; Solano Salinas, C J; Tagg, N; Tice, B G; Valencia, E; Walton, T; Wolcott, J; Wospakrik, M; Zavala, G; Zhang, D

    2016-02-19

    Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current ν_{μ} interactions is combined with muon kinematics to permit separation of the quasielastic and Δ(1232) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and Δ resonance processes are needed to describe the data. The data in this kinematic region also have an enhanced population of multiproton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments. PMID:26943528

  3. Genetic Drift Can Compromise Mitochondrial Replacement by Nuclear Transfer in Human Oocytes.

    PubMed

    Yamada, Mitsutoshi; Emmanuele, Valentina; Sanchez-Quintero, Maria J; Sun, Bruce; Lallos, Gregory; Paull, Daniel; Zimmer, Matthew; Pagett, Shardonay; Prosser, Robert W; Sauer, Mark V; Hirano, Michio; Egli, Dieter

    2016-06-01

    Replacement of mitochondria through nuclear transfer between oocytes of two different women has emerged recently as a strategy for preventing inheritance of mtDNA diseases. Although experiments in human oocytes have shown effective replacement, the consequences of small amounts of mtDNA carryover have not been studied sufficiently. Using human mitochondrial replacement stem cell lines, we show that, even though the low levels of heteroplasmy introduced into human oocytes by mitochondrial carryover during nuclear transfer often vanish, they can sometimes instead result in mtDNA genotypic drift and reversion to the original genotype. Comparison of cells with identical oocyte-derived nuclear DNA but different mtDNA shows that either mtDNA genotype is compatible with the nucleus and that drift is independent of mitochondrial function. Thus, although functional replacement of the mitochondrial genome is possible, even low levels of heteroplasmy can affect the stability of the mtDNA genotype and compromise the efficacy of mitochondrial replacement. PMID:27212703

  4. Identification of nuclear effects in neutrino-carbon interactions at low three-momentum transfer

    DOE PAGESBeta

    Rodrigues, P. A.

    2016-02-17

    Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current νμ interactions is combined with muon kinematics to permit separation of the quasielastic and Δ(1232) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and Δ resonance processes are needed to describe the data. The data in this kinematic region also have an enhanced populationmore » of multiproton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Furthermore, improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments.« less

  5. Coupled electron-nuclear dynamics: Charge migration and charge transfer initiated near a conical intersection

    NASA Astrophysics Data System (ADS)

    Mendive-Tapia, David; Vacher, Morgane; Bearpark, Michael J.; Robb, Michael A.

    2013-07-01

    Coupled electron-nuclear dynamics, implemented using the Ehrenfest method, has been used to study charge migration with fixed nuclei, together with charge transfer when nuclei are allowed to move. Simulations were initiated at reference geometries of neutral benzene and 2-phenylethylamine (PEA), and at geometries close to potential energy surface crossings in the cations. Cationic eigenstates, and the so-called sudden approximation, involving removal of an electron from a correlated ground-state wavefunction for the neutral species, were used as initial conditions. Charge migration without coupled nuclear motion could be observed if the Ehrenfest simulation, using the sudden approximation, was started near a conical intersection where the states were both strongly coupled and quasi-degenerate. Further, the main features associated with charge migration were still recognizable when the nuclear motion was allowed to couple. In the benzene radical cation, starting from the reference neutral geometry with the sudden approximation, one could observe sub-femtosecond charge migration with a small amplitude, which results from weak interaction with higher electronic states. However, we were able to engineer large amplitude charge migration, with a period between 10 and 100 fs, corresponding to oscillation of the electronic structure between the quinoid and anti-quinoid cationic electronic configurations, by distorting the geometry along the derivative coupling vector from the D6h Jahn-Teller crossing to lower symmetry where the states are not degenerate. When the nuclear motion becomes coupled, the period changes only slightly. In PEA, in an Ehrenfest trajectory starting from the D2 eigenstate and reference geometry, a partial charge transfer occurs after about 12 fs near the first crossing between D1, D2 (N+-Phenyl, N-Phenyl+). If the Ehrenfest propagation is started near this point, using the sudden approximation without coupled nuclear motion, one observes an

  6. Coupled electron-nuclear dynamics: charge migration and charge transfer initiated near a conical intersection.

    PubMed

    Mendive-Tapia, David; Vacher, Morgane; Bearpark, Michael J; Robb, Michael A

    2013-07-28

    Coupled electron-nuclear dynamics, implemented using the Ehrenfest method, has been used to study charge migration with fixed nuclei, together with charge transfer when nuclei are allowed to move. Simulations were initiated at reference geometries of neutral benzene and 2-phenylethylamine (PEA), and at geometries close to potential energy surface crossings in the cations. Cationic eigenstates, and the so-called sudden approximation, involving removal of an electron from a correlated ground-state wavefunction for the neutral species, were used as initial conditions. Charge migration without coupled nuclear motion could be observed if the Ehrenfest simulation, using the sudden approximation, was started near a conical intersection where the states were both strongly coupled and quasi-degenerate. Further, the main features associated with charge migration were still recognizable when the nuclear motion was allowed to couple. In the benzene radical cation, starting from the reference neutral geometry with the sudden approximation, one could observe sub-femtosecond charge migration with a small amplitude, which results from weak interaction with higher electronic states. However, we were able to engineer large amplitude charge migration, with a period between 10 and 100 fs, corresponding to oscillation of the electronic structure between the quinoid and anti-quinoid cationic electronic configurations, by distorting the geometry along the derivative coupling vector from the D6h Jahn-Teller crossing to lower symmetry where the states are not degenerate. When the nuclear motion becomes coupled, the period changes only slightly. In PEA, in an Ehrenfest trajectory starting from the D2 eigenstate and reference geometry, a partial charge transfer occurs after about 12 fs near the first crossing between D1, D2 (N(+)-Phenyl, N-Phenyl(+)). If the Ehrenfest propagation is started near this point, using the sudden approximation without coupled nuclear motion, one observes an

  7. Coupled electron-nuclear dynamics: Charge migration and charge transfer initiated near a conical intersection

    SciTech Connect

    Mendive-Tapia, David; Vacher, Morgane; Bearpark, Michael J.; Robb, Michael A.

    2013-07-28

    Coupled electron-nuclear dynamics, implemented using the Ehrenfest method, has been used to study charge migration with fixed nuclei, together with charge transfer when nuclei are allowed to move. Simulations were initiated at reference geometries of neutral benzene and 2-phenylethylamine (PEA), and at geometries close to potential energy surface crossings in the cations. Cationic eigenstates, and the so-called sudden approximation, involving removal of an electron from a correlated ground-state wavefunction for the neutral species, were used as initial conditions. Charge migration without coupled nuclear motion could be observed if the Ehrenfest simulation, using the sudden approximation, was started near a conical intersection where the states were both strongly coupled and quasi-degenerate. Further, the main features associated with charge migration were still recognizable when the nuclear motion was allowed to couple. In the benzene radical cation, starting from the reference neutral geometry with the sudden approximation, one could observe sub-femtosecond charge migration with a small amplitude, which results from weak interaction with higher electronic states. However, we were able to engineer large amplitude charge migration, with a period between 10 and 100 fs, corresponding to oscillation of the electronic structure between the quinoid and anti-quinoid cationic electronic configurations, by distorting the geometry along the derivative coupling vector from the D{sub 6h} Jahn-Teller crossing to lower symmetry where the states are not degenerate. When the nuclear motion becomes coupled, the period changes only slightly. In PEA, in an Ehrenfest trajectory starting from the D{sub 2} eigenstate and reference geometry, a partial charge transfer occurs after about 12 fs near the first crossing between D{sub 1}, D{sub 2} (N{sup +}-Phenyl, N-Phenyl{sup +}). If the Ehrenfest propagation is started near this point, using the sudden approximation without coupled

  8. Human-mouse interspecies collagen I heterotrimer is functional during embryonic development of Mov13 mutant mouse embryos.

    PubMed Central

    Wu, H; Bateman, J F; Schnieke, A; Sharpe, A; Barker, D; Mascara, T; Eyre, D; Bruns, R; Krimpenfort, P; Berns, A

    1990-01-01

    To investigate whether the human pro alpha 1(I) collagen chain could form an in vivo functional interspecies heterotrimer with the mouse pro alpha 2(I) collagen chain, we introduced the human COL1A1 gene into Mov13 mice which have a functional deletion of the endogenous COL1A1 gene. Transgenic mouse strains (HucI and HucII) carrying the human COL1A1 gene were first generated by microinjecting the COL1A1 gene into wild-type mouse embryos. Genetic evidence indicated that the transgene in the HucI strain was closely linked to the endogenous mouse COL1A1 gene and was X linked in the HucII transgenic strain. Northern (RNA) blot and S1 protection analyses showed that the transgene was expressed in the appropriate tissue-specific manner and as efficiently as the endogenous COL1A1 gene. HucII mice were crossed with Mov13 mice to transfer the human transgene into the mutant strain. Whereas homozygous Mov13 embryos die between days 13 and 14 of gestation, the presence of the transgene permitted apparently normal development of the mutant embryos to birth. This indicated that the mouse-human interspecies collagen I heterotrimer was functional in the animal. The rescue was, however, only partial, as all homozygotes died within 36 h after delivery, with signs of internal bleeding. This could have been due to a functional defect in the interspecies hybrid collagen. Extensive analysis failed to reveal any biochemical or morphological abnormalities of the collagen I molecules in Mov13-HucII embryos.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:1690840

  9. Cats cloned from fetal and adult somatic cells by nuclear transfer.

    PubMed

    Yin, X J; Lee, H S; Lee, Y H; Seo, Y I; Jeon, S J; Choi, E G; Cho, S J; Cho, S G; Min, W; Kang, S K; Hwang, W S; Kong, I K

    2005-02-01

    This work was undertaken in order to study the developmental competence of nuclear transfer (NT) into cat embryos using fetal fibroblast and adult skin fibroblast cells as donor nuclei. Oocytes were recovered by mincing the ovaries in Hepes-buffered TCM199 and selecting the cumulus oocyte complexes (COCs) with compact cumulus cell mass and dark color. Homogenous ooplasm was cultured for maturation in TCM199+10% fetal bovine serum (FBS) for 12 h and used as a source of recipient cytoplast for exogenous somatic nuclei. In experiment 1, we evaluated the effect of donor cell type on the reconstruction and development of cloned embryos. Fusion, first cleavage and blastocyst developmental rate were not different between fetal fibroblasts and adult skin cells (71.2 vs 66.8; 71.0 vs 57.6; 4.0 vs 6.1% respectively; P < 0.05). In experiment 2, cloned embryos were surgically transferred into the oviducts of recipient queens. One of the seven recipient queens was delivered naturally of 2 healthy cloned cats and 1 stillborn from fetal fibroblast cells of male origin 65 days after embryo transfer. One of three recipient queens was delivered naturally of 1 healthy cloned cat from adult skin cells of female origin 65 days after embryo transfer. The cloned cats showed genotypes identical to the donor cell lines, indicating that adult somatic cells can be used for feline cloning. PMID:15695619

  10. Cytoplasmic Inheritance of Transplantation Antigens In Animals Produced by Nuclear Transfer

    PubMed Central

    Hanekamp, John S.; Okumi, Masayoshi; Tena, Aseda; Arn, Scott; Yamada, Kazuhiko; Sachs, David H.

    2010-01-01

    Background Nuclear transfer has been utilized as a means of selectively modifying the mammalian genome. One possible consequence of this technology is that the oocytes used in nuclear transfer may provide additional antigens via cytoplasmic inheritance of maternally derived, mitochondrial DNA. These studies examine the potential consequences of such inheritance in a large animal transplantation model. Methods Renal transplants were performed between MHC-identical animals differing only in the source of their maternally derived cytoplasmic DNA, using a protocol which uniformly leads to tolerance within standard MHC-inbred lines. In an attempt to correlate transplant results with a putative marker for disparities in cytoplasmically inherited minor histocompatibility antigens, we examined one hypervariable region of mitochondrial DNA (mtDNA), designated HV1. Results The mtDNA sequence of the HV1 region was found to be invariant among MGH miniature swine of different haplotypes, despite twenty years of selective breeding of the sublines of this colony. In contrast, swine derived by nuclear transfer into outbred oocytes differed in the HV1 region sequence from each other and from MGH swine. Renal transplants from standard, inbred MGH swine to their MHC-identical knockout counterparts derived from outbred oocytes were rejected within two weeks, while transplants in the reverse direction were accepted for over 30 days. Conclusions The HV1 sequence of mtDNA may serve as a marker for the level of diversity of mtDNA. These transplant data are consistent with the existence of mtDNA-encoded mitochondrial minor antigens with a similar level of diversity that can influence the outcome of renal transplantation. PMID:19584677

  11. Nuclear transfer of porcine embryos using cryopreserved delipated blastomeres as donor nuclei.

    PubMed

    Nagashima, H; Ashman, R J; Nottle, M B

    1997-11-01

    Nuclear transfer protocol for the pig using cryopreserved delipated four- to eight-cell and morula stage embryos as nucleus donors was developed. Donor embryos, which had been delipated by micromanipulation following centrifugation for polarizing cytoplasmic lipid droplets, were cryopreserved with 1.5 M 1,2-propanediol and 0.1 M sucrose. Recipient cytoplasts were prepared from ovulated oocytes. Activation of oocytes could be induced more efficiently when electric stimulation was given 53 hr after the hCG injection or later (66-83%), compared with 52 hr or earlier (11-16%, P < 0.05), suggesting that aging after ovulation may be required for in vivo matured porcine oocytes to be activated by electric stimuli. Membrane fusion rates between donor blastomeres and enucleated oocytes were 88% (127/144) and 97% (56/58, P > 0.05) for the four- to eight-cell and morula stage embryos, respectively. In vitro developmental rates to the two-cell (53/100 vs. 35/65), four-cell (34/100 vs. 26/65), and morula stage (17/100 vs. 18/65) were the same between the nuclear transfer embryos with four- to eight-cell and morula nuclei. However, more embryos reconstituted with morula nuclei developed to blastocysts (15% vs. 6%, P < 0.05). These data demonstrated that blastomeres of cryopreserved, delipated porcine embryos can be used as donor nuclei for nuclear transfer. Frozen-thawed, delipated blastomeres can be efficiently isolated and fused, and therefore provide a useful source of donor nuclei. PMID:9322245

  12. Nuclear propulsion systems for orbit transfer based on the particle bed reactor

    SciTech Connect

    Powell, J.R.; Ludewig, H.; Horn, F.L.; Araj, K.; Benenati, R.; Lazareth, O.; Slovik, G.; Solon, M.; Tappe, W.; Belisle, J.

    1987-01-01

    The technology of nuclear direct propulsion orbit transfer systems based on the Particle Bed Reactor (PBR) is described. A 200 megawatt illustrative design is presented for LEO to GEO and other high ..delta..V missions. The PBR-NOTV can be used in a one-way mode with the shuttle or an expendable launch vehicle, e.g., the Titan 34D7, or as a two-way reusable space tug. In the one-way mode, payload capacity is almost three times greater than that of chemical OTV's. PBR technology status is described and development needs outlined.

  13. Somatic cell nuclear transfer-derived embryonic stem cell lines in humans: pros and cons.

    PubMed

    Langerova, Alena; Fulka, Helena; Fulka, Josef

    2013-12-01

    The recent paper, published by Mitalipov's group in Cell (Tachibana et al., 2013 ), reporting the production of human somatic cell nuclear transfer (SCNT) embryonic stem cells (ESCs), opens again the debate if, in the era of induced pluripotent stem cells (iPSCs), the production of these cells is indeed necessary and, if so, whether they are different from ESCs produced from spare embryos and iPSCs. It is our opinion that these questions are very difficult to answer because it is still unclear whether and how normal ESCs differ from iPSCs. PMID:24180743

  14. Development of porcine tetraploid somatic cell nuclear transfer embryos is influenced by oocyte nuclei.

    PubMed

    Fu, Bo; Liu, Di; Ma, Hong; Guo, Zhen-Hua; Wang, Liang; Li, Zhong-Qiu; Peng, Fu-Gang; Bai, Jing

    2016-02-01

    Cloning efficiency in mammalian systems remains low because reprogramming of donor cells is frequently incomplete. Nuclear factors in the oocyte are removed by enucleation, and this removal may adversely affect reprogramming efficiency. Here, we investigated the role of porcine oocyte nuclear factors during reprogramming. We introduced somatic cell nuclei into intact MII oocytes to establish tetraploid somatic cell nuclear transfer (SCNT) embryos containing both somatic nuclei and oocyte nuclei. We then examined the influence of the oocyte nucleus on tetraploid SCNT embryo development by assessing characteristics including pronucleus formation, cleavage rate, and blastocyst formation. Overall, tetraploid SCNT embryos have a higher developmental competence than do standard diploid SCNT embryos. Therefore, we have established an embryonic model in which a fetal fibroblast nucleus and an oocyte metaphase II plate coexist. Tetraploid SCNT represents a new research platform that is potentially useful for examining interactions between donor nuclei and oocyte nuclei. This platform should facilitate further understanding of the roles played by nuclear factors during reprogramming. PMID:26503330

  15. Nuclear event time histories and computed site transfer functions for locations in the Los Angeles region

    USGS Publications Warehouse

    Rogers, A.M.; Covington, P.A.; Park, R.B.; Borcherdt, R.D.; Perkins, D.M.

    1980-01-01

    This report presents a collection of Nevada Test Site (NTS) nuclear explosion recordings obtained at sites in the greater Los Angeles, Calif., region. The report includes ground velocity time histories, as well as, derived site transfer functions. These data have been collected as part of a study to evaluate the validity of using low-level ground motions to predict the frequency-dependent response of a site during an earthquake. For this study 19 nuclear events were recorded at 98 separate locations. Some of these sites have recorded more than one of the nuclear explosions, and, consequently, there are a total of 159, three-component station records. The location of all the recording sites are shown in figures 1–5, the station coordinates and abbreviations are given in table 1. The station addresses are listed in table 2, and the nuclear explosions that were recorded are listed in table 3. The recording sites were chosen on the basis of three criteria: (1) that the underlying geological conditions were representative of conditions over significant areas of the region, (2) that the site was the location of a strong-motion recording of the 1971 San Fernando earthquake, or (3) that more complete geographical coverage was required in that location.

  16. Comparative Analysis of Nuclear Transfer Embryo-Derived Mouse Embryonic Stem Cells. Part I: Cellular Characterization

    PubMed Central

    Kobolak, Julianna; Mamo, Solomon; Rungsiwiwut, Ruttachuk; Ujhelly, Olga; Csonka, Erika; Hadlaczky, Gyula

    2012-01-01

    Abstract Embryonic stem cells derived from nuclear transfer embryos (ntESCs) are particularly valuable for regenerative medicine, as they are a patient-specific and histocompatible cell source for the treatment of varying diseases. However, currently, little is known about their cellular and molecular profile. In the present study, in a mouse model different donor cell-derived ntESCs from various genetic backgrounds were compared with reference ESCs and analyzed comprehensively at the cellular level. A number of pluripotency marker genes were compared by flow cytometry and immunocytochemistry analysis. Significant differences at the protein level were observed for POU5F1, SOX2, FGF4, NANOG, and SSEA-1. However, such differences had no effect on in vitro cell differentiation and cell fate: derivatives of the three germ layers were detected in all ntESC lines. The neural and cardiac in vitro differentiation revealed minor differences between the cell lines, both at the mRNA and protein level. Karyotype analyses and cell growth studies did not reveal any significant variations. Despite some differences observed, the present study revealed that ntESC lines had similar differentiation competences compared to other ESCs. The results indicate that the observed differences may be related to the genotype rather than to the nuclear transfer technology. PMID:22204592

  17. Targeted disruption of Ataxia-telangiectasia mutated gene in miniature pigs by somatic cell nuclear transfer

    SciTech Connect

    Kim, Young June; Ahn, Kwang Sung; Kim, Minjeong; Kim, Min Ju; Park, Sang-Min; Ryu, Junghyun; Ahn, Jin Seop; Heo, Soon Young; Kang, Jee Hyun; Choi, You Jung; Choi, Seong-Jun; Shim, Hosup

    2014-10-03

    Highlights: • ATM gene-targeted pigs were produced by somatic cell nuclear transfer. • A novel large animal model for ataxia telangiectasia was developed. • The new model may provide an alternative to the mouse model. - Abstract: Ataxia telangiectasia (A-T) is a recessive autosomal disorder associated with pleiotropic phenotypes, including progressive cerebellar degeneration, gonad atrophy, and growth retardation. Even though A-T is known to be caused by the mutations in the Ataxia telangiectasia mutated (ATM) gene, the correlation between abnormal cellular physiology caused by ATM mutations and the multiple symptoms of A-T disease has not been clearly determined. None of the existing ATM mouse models properly reflects the extent to which neurological degeneration occurs in human. In an attempt to provide a large animal model for A-T, we produced gene-targeted pigs with mutations in the ATM gene by somatic cell nuclear transfer. The disrupted allele in the ATM gene of cloned piglets was confirmed via PCR and Southern blot analysis. The ATM gene-targeted pigs generated in the present study may provide an alternative to the current mouse model for the study of mechanisms underlying A-T disorder and for the development of new therapies.

  18. Somatic cell nuclear transfer: Infinite reproduction of a unique diploid genome

    SciTech Connect

    Kishigami, Satoshi Wakayama, Sayaka; Hosoi, Yoshihiko; Iritani, Akira; Wakayama, Teruhiko

    2008-06-10

    In mammals, a diploid genome of an individual following fertilization of an egg and a spermatozoon is unique and irreproducible. This implies that the generated unique diploid genome is doomed with the individual ending. Even as cultured cells from the individual, they cannot normally proliferate in perpetuity because of the 'Hayflick limit'. However, Dolly, the sheep cloned from an adult mammary gland cell, changes this scenario. Somatic cell nuclear transfer (SCNT) enables us to produce offspring without germ cells, that is, to 'passage' a unique diploid genome. Animal cloning has also proven to be a powerful research tool for reprogramming in many mammals, notably mouse and cow. The mechanism underlying reprogramming, however, remains largely unknown and, animal cloning has been inefficient as a result. More momentously, in addition to abortion and fetal mortality, some cloned animals display possible premature aging phenotypes including early death and short telomere lengths. Under these inauspicious conditions, is it really possible for SCNT to preserve a diploid genome? Delightfully, in mouse and recently in primate, using SCNT we can produce nuclear transfer ES cells (ntES) more efficiently, which can preserve the eternal lifespan for the 'passage' of a unique diploid genome. Further, new somatic cloning technique using histone-deacetylase inhibitors has been developed which can significantly increase the previous cloning rates two to six times. Here, we introduce SCNT and its value as a preservation tool for a diploid genome while reviewing aging of cloned animals on cellular and individual levels.

  19. Nuclear transfer procedures in the ovine can induce early embryo fragmentation and compromise cloned embryo development.

    PubMed

    Xue, Lian; Cheng, Lei; Su, Guanghua; Kang, Feng; Wu, Xia; Bai, Chunling; Zhang, Li; Li, Guang-Peng

    2011-07-01

    Cytoplasmic fragmentations are frequently observed in early mammalian embryos, and especially in the human. In our research we have observed subtle clues that the occurrence of fragmentation was most likely a result of somatic cell nuclear transfer (NT) protocols, and in particular, the in vitro culture system. In this study we examined various putative factors that might induce early embryo fragmentation in the ovine. The results indicate that nuclear transfer protocols such as the fusion parameter, activation treatment, and especially the choice of culture medium affected embryo cleavage rates and resulted in a higher incidence of fragmented embryos. Upon using the same fusion parameter, activation parameters that were based upon amino acids containing synthetic oviduct fluids (SOFaa) culture system resulted in significantly lower fragmentation rates than when utilizing a Charles Rosenkrans 1 (CR1aa) culture system. Fragmented embryos typically exhibited irregular numbers of blastomeres with the majority of blastomeres devoid of chromatin. Factors such as fusion DC pulse, activation treatment and culture system led to higher fragmentation and also affected in vitro and in vivo embryo development. The SOFaa based culture system produced a higher number of quality NT embryos resulting in higher pregnancy rates and the birth of live lambs as compared to the CR1aa based system (P<0.05). We conclude that early embryo fragmentation in the ovine is caused by suboptimal cloning protocols, and NT embryo development is especially affected by the culture system used. PMID:21700405

  20. Distribution and interspecies contact of feral swine and cattle on rangeland in south Texas: implications for disease transmission.

    PubMed

    Cooper, Susan M; Scott, H Morgan; de la Garza, Guadalupe R; Deck, Aubrey L; Cathey, James C

    2010-01-01

    The last outbreak of foot-and-mouth disease (FMD) in the United States occurred in 1929. Since that time, numbers and distribution of feral swine (Sus scrofa) have increased greatly, especially in the southern states. This creates a potential risk to livestock production because swine are susceptible to, and can be carriers of, several economically harmful diseases of livestock. Most importantly, swine are potent amplifiers of FMD virus. In this study, global positioning system (GPS) collars were placed on rangeland cattle (Bos indicus x taurus) and feral swine to determine shared habitat use by these species on a large ranch in south Texas from 2004 to 2006. The aim was to identify locations and rates of interspecies contact that may result in effective transfer of FMD virus, should an outbreak occur. In shrubland and riparian areas, animals were dispersed, so contacts within and between species were relatively infrequent. Indirect contacts, whereby cattle and feral swine used the same location (within 20 m) within a 360-min period, occurred primarily at water sources, and seasonally in irrigated forage fields and along ranch roads. Direct contacts between species (animals <20 m apart and within 15 min) were rare and occurred primarily at water sources. Changes in ranch management practices are suggested to reduce interspecies contact should an FMD disease outbreak occur. This information can also be used to improve current epidemiologic models to better fit free-ranging animal populations. PMID:20090028

  1. Transfer of 137Cs from Chernobyl debris and nuclear weapons fallout to different Swedish population groups.

    PubMed

    Rääf, C L; Hubbard, L; Falk, R; Agren, G; Vesanen, R

    2006-08-15

    Data from measurements on the body burden of (134)Cs, (137)Cs and (40)K in various Swedish populations between 1959 and 2001 has been compiled into a national database. The compilation is a co-operation between the Departments of Radiation Physics in Malmö and Göteborg, the National Radiation Protection Authority (SSI) and the Swedish Defense Research Agency (FOI). In a previous study the effective ecological half time and the associated effective dose to various Swedish populations due to internal contamination of (134)Cs and (137)Cs have been assessed using the database. In this study values of human body burden have been combined with data on the local and regional ground deposition of fallout from nuclear weapons tests (only (137)Cs) and Chernobyl debris (both (134)Cs and (137)Cs), which have enabled estimates of the radioecological transfer in the studied populations. The assessment of the database shows that the transfer of radiocesium from Chernobyl fallout to humans varies considerably between various populations in Sweden. In terms of committed effective dose over a 70 y period from internal contamination per unit activity deposition, the general (predominantly urban) Swedish population obtains 20-30 microSv/kBq m(-2). Four categories of populations exhibit higher radioecological transfer than the general population; i.) reindeer herders ( approximately 700 microSv/kBq m(-2)), ii.) hunters in the counties dominated by forest vegetation ( approximately 100 microSv/kBq m(-2)), iii.) rural non-farming populations living in sub-arctic areas (40-150 microSv/kBq m(-2)), and iv.) farmers ( approximately 50 microSv/kBq m(-2)). Two important factors determine the aggregate transfer from ground deposition to man; i.) dietary habits (intakes of foodstuff originating from natural and semi-natural ecosystems), and ii.) inclination to follow the recommended food restriction by the authorities. The transfer to the general population is considerably lower

  2. Application of Direct Assessment Approaches and Methodologies to Cathodically Protected Nuclear Waste Transfer Lines

    SciTech Connect

    Dahl, Megan M.; Pikas, Joseph; Edgemon, Glenn L.; Philo, Sarah

    2013-01-22

    The U.S. Department of Energy's (DOE) Hanford Site is responsible for the safe storage, retrieval, treatment, and disposal of approximately 54 million gallons (204 million liters) of radioactive waste generated since the site's inception in 1943. Today, the major structures involved in waste management at Hanford include 149 carbon steel single-shell tanks, 28 carbon-steel double-shell tanks, plus a network of buried metallic transfer lines and ancillary systems (pits, vaults, catch tanks, etc.) required to store, retrieve, and transfer waste within the tank farm system. Many of the waste management systems at Hanford are still in use today. In response to uncertainties regarding the structural integrity of these systems,' an independent, comprehensive integrity assessment of the Hanford Site piping system was performed. It was found that regulators do not require the cathodically protected pipelines located within the Hanford Site to be assessed by External Corrosion Direct Assessment (ECDA) or any other method used to ensure integrity. However, a case study is presented discussing the application of the direct assessment process on pipelines in such a nuclear environment. Assessment methodology and assessment results are contained herein. An approach is described for the monitoring, integration of outside data, and analysis of this information in order to identify whether coating deterioration accompanied by external corrosion is a threat for these waste transfer lines.

  3. Unusual horizontal transfer of a long interspersed nuclear element between distant vertebrate classes.

    PubMed

    Kordis, D; Gubensek, F

    1998-09-01

    We have shown previously by Southern blot analysis that Bov-B long interspersed nuclear elements (LINEs) are present in different Viperidae snake species. To address the question as to whether Bov-B LINEs really have been transmitted horizontally between vertebrate classes, the analysis has been extended to a larger number of vertebrate, invertebrate, and plant species. In this paper, the evolutionary origin of Bov-B LINEs is shown unequivocally to be in Squamata. The previously proposed horizontal transfer of Bov-B LINEs in vertebrates has been confirmed by their discontinuous phylogenetic distribution in Squamata (Serpentes and two lizard infra-orders) as well as in Ruminantia, by the high level of nucleotide identity, and by their phylogenetic relationships. The horizontal transfer of Bov-B LINEs from Squamata to the ancestor of Ruminantia is evident from the genetic distances and discontinuous phylogenetic distribution. The ancestor of Colubroidea snakes is a possible donor of Bov-B LINEs to Ruminantia. The timing of horizontal transfer has been estimated from the distribution of Bov-B LINEs in Ruminantia and the fossil data of Ruminantia to be 40-50 My ago. The phylogenetic relationships of Bov-B LINEs from the various Squamata species agrees with that of the species phylogeny, suggesting that Bov-B LINEs have been maintained stably by vertical transmission since the origin of Squamata in the Mesozoic era. PMID:9724768

  4. Piglets born from vitrified cloned blastocysts produced with a simplified method of delipation and nuclear transfer.

    PubMed

    Du, Yutao; Li, Juan; Kragh, Peter M; Zhang, Yunhai; Schmidt, Mette; Bøgh, Ingrid B; Zhang, Xiuqing; Purup, Stig; Kuwayama, M; Jørgensen, Arne L; Pedersen, Anette M; Villemoes, Klaus; Yang, Huanming; Bolund, Lars; Vajta, Gábor

    2007-01-01

    Successful cryopreservation of porcine embryos offers a promising perspective in the fields of agriculture, animal science, and human medical research. The objective of the present work was to establish a system facilitating the cryopreservation of porcine embryos produced by somatic cell nuclear transfer (SCNT). Several key techniques including micromanipulator-based enucleation, noninvasive delipation, zona-free fusion, and activation were combined with high efficiency. After a partial zona digestion and high-speed centrifugation, 89.8+/-2.1% (mean+/-SEM) of enucleated oocytes were successfully delipated. Delipated cytoplasts were incubated for an additional 0.5 or 2 h before fusion with somatic cells. After activation and 6 days of in vitro culture, no significant difference in the rate of blastocysts per reconstructed embryo was observed between the two groups (33.1+/-1.8% and 26.0+/-4.3% for 0.5 and 2 h recovery time, respectively). Cryopreservation of the blastocysts was performed with a Cryotop device and factory-prepared vitrification and warming solutions. One hundred fifty-five vitrified SCNT embryos were transferred surgically into two recipient sows to test their developmental capacity in vivo. One recipient became pregnant and delivered six piglets. In conclusion, our simplified delipation and SCNT procedure resulted in viable piglets after vitrification and embryo transfer at the blastocyst stage. PMID:18154508

  5. Interspecies communication between plant and mouse gut host cells through edible plant derived exosome-like nanoparticles

    PubMed Central

    Mu, Jingyao; Zhuang, Xiaoying; Wang, Qilong; Jiang, Hong; Deng, Zhong-Bin; Wang, Baomei; Zhang, Lifeng; Kakar, Sham; Jun, Yan; Miller, Donald; Zhang, Huang-Ge

    2015-01-01

    Scope Exosomes, small vesicles participating in intercellular communication have been extensively studied recently; however, the role of edible plant derived exosomes in interspecies communication has not been investigated. Here, we investigate the biological effects of edible plant derived exosome-like nanoparticles (EPDEN) on mammalian cells. Methods and results In this study, exosome-like nanoparticles from four edible plants were isolated and characterized. We show that these EPDENs contain proteins, lipids and microRNA. EPDENs are taken up by intestinal macrophages and stem cells. The results generated from EPDEN transfected macrophages indicate that ginger EPDENs preferentially induce the expression of the anti-oxidation gene, heme oxygenase-1 (HO-1) and the anti-inflammatory cytokine, IL-10; whereas grapefruit, ginger, and carrot EPDENs promote activation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2). Furthermore, analysis of the intestines of canonical Wnt reporter mice, i.e., B6.Cg-Tg(BAT-lacZ)3Picc/J mice, revealed that the numbers of β-galactosidase+ (β-Gal) intestinal crypts are increased, suggesting that EPDEN treatment of mice leads to Wnt mediated activation of the Tcf4 transcription machinery in the crypts. Conclusion The data suggest a role for EPDEN mediated interspecies communication by inducing expression of genes for anti-inflammation cytokines, anti-oxidation and activation of Wnt signaling, which are crucial for maintaining intestinal homeostasis. PMID:24842810

  6. International remote monitoring project Argentina Nuclear Power Station Spent Fuel Transfer Remote Monitoring System

    SciTech Connect

    Schneider, S.; Lucero, R.; Glidewell, D.

    1997-08-01

    The Autoridad Regulataria Nuclear (ARN) and the United States Department of Energy (DOE) are cooperating on the development of a Remote Monitoring System for nuclear nonproliferation efforts. A Remote Monitoring System for spent fuel transfer will be installed at the Argentina Nuclear Power Station in Embalse, Argentina. The system has been designed by Sandia National Laboratories (SNL), with Los Alamos National Laboratory (LANL) and Oak Ridge National Laboratory (ORNL) providing gamma and neutron sensors. This project will test and evaluate the fundamental design and implementation of the Remote Monitoring System in its application to regional and international safeguards efficiency. This paper provides a description of the monitoring system and its functions. The Remote Monitoring System consists of gamma and neutron radiation sensors, RF systems, and video systems integrated into a coherent functioning whole. All sensor data communicate over an Echelon LonWorks Network to a single data logger. The Neumann DCM 14 video module is integrated into the Remote Monitoring System. All sensor and image data are stored on a Data Acquisition System (DAS) and archived and reviewed on a Data and Image Review Station (DIRS). Conventional phone lines are used as the telecommunications link to transmit on-site collected data and images to remote locations. The data and images are authenticated before transmission. Data review stations will be installed at ARN in Buenos Aires, Argentina, ABACC in Rio De Janeiro, IAEA Headquarters in Vienna, and Sandia National Laboratories in Albuquerque, New Mexico. 2 refs., 2 figs.

  7. The influence of donor nucleus source on the outcome of zebrafish somatic cell nuclear transfer.

    PubMed

    Siripattarapravat, Kannika; Pinmee, Boonya; Chang, Eun-Ah; Muñoz, Juan D; Kawakami, Koichi; Cibelli, José B

    2010-01-01

    The success of nuclear reprogramming following somatic cell nuclear transfer (SCNT) is thought to depend on factors present in the egg. Little is known about the role - if any - played by the somatic cell type on the outcome of the procedure. We tested whether cells of different lineages might have different capacities for reprogramming following SCNT, comparing cells isolated from five different tissues of transgenic zebrafish for their developmental potential when used as SCNT donor cells. We used transgenic zebrafish lines expressing green fluorescence protein under an endogenous tissue-specific promoter: HGn62A-skin, HGn28A-skin, HGn8E-heart, HG21C-fin and notochord and HGn30A-hatch gland. We analyzed the efficiency of cloning, as measured by reconstructed embryos that developed up to the hatched-fry stage. Specifically, donor cells of fin and notochord origin yielded the best rate of cloned fish production. All of the other cell types used were capable of producing cloned fish, albeit with significantly lower efficiency. These results indicate that the type of zebrafish cells used for SCNT can influence the outcome of the procedure. Future epigenetic analysis of these cells will help determine specific chromatin profiles in somatic cells that have an impact on nuclear reprogramming procedures. PMID:21404188

  8. Effect of epigenetic modification with trichostatin A and S-adenosylhomocysteine on developmental competence and POU5F1-EGFP expression of interspecies cloned embryos in dog.

    PubMed

    Mousai, M; Hosseini, S M; Hajian, M; Jafarpour, F; Asgari, V; Forouzanfar, M; Nasr-Esfahani, M H

    2015-10-01

    Adult canine fibroblasts stably transfected with either cytomegalovirus (CMV) or POU5F1 promoter-driven enhanced green fluorescent protein (EGFP) were used to investigate if pre-treatment of these donor cells with two epigenetic drugs [trichostatin A (TSA), or S-adenosylhomocysteine (SAH)] can improve the efficiency of interspecies somatic cell nuclear transfer (iSCNT). Fluorescence-activated cell sorting (FACS), analyses revealed that TSA, but not SAH, treatment of both transgenic and non-transgenic fibroblasts significantly increased acetylation levels compared with untreated relatives. The expression levels of Bcl2 and P53 were significantly affected in TSA-treated cells compared with untreated cells, whereas SAH treatment had no significant effect on cell apoptosis. Irrespective of epigenetic modification, dog/bovine iSCNT embryos had overall similar rates of cleavage and development to 8-16-cell and morula stages in non-transgenic groups. For transgenic reconstructed embryos, however, TSA and SAH could significantly improve development to 8-16-cell and morula stages compared with control. Even though, irrespective of cell transgenesis and epigenetic modification, none of the iSCNT embryos developed to the blastocyst stage. The iSCNT embryos carrying CMV-EGFP expressed EGFP at all developmental stages (2-cell, 4-cell, 8-16-cell, and morula) without mosaicism, while no POU5F1-EGFP signal was observed in any stage of developing iSCNT embryos irrespective of TSA/SAH epigenetic modifications. These results indicated that bovine oocytes partially remodel canine fibroblasts and that TSA and SAH have marginal beneficial effects on this process. PMID:25314965

  9. Heat Transfer Enhancement By Three-Dimensional Surface Roughness Technique In Nuclear Fuel Rod Bundles

    NASA Astrophysics Data System (ADS)

    Najeeb, Umair

    This thesis experimentally investigates the enhancement of single-phase heat transfer, frictional loss and pressure drop characteristics in a Single Heater Element Loop Tester (SHELT). The heater element simulates a single fuel rod for Pressurized Nuclear reactor. In this experimental investigation, the effect of the outer surface roughness of a simulated nuclear rod bundle was studied. The outer surface of a simulated fuel rod was created with a three-dimensional (Diamond-shaped blocks) surface roughness. The angle of corrugation for each diamond was 45 degrees. The length of each side of a diamond block is 1 mm. The depth of each diamond block was 0.3 mm. The pitch of the pattern was 1.614 mm. The simulated fuel rod had an outside diameter of 9.5 mm and wall thickness of 1.5 mm and was placed in a test-section made of 38.1 mm inner diameter, wall thickness 6.35 mm aluminum pipe. The Simulated fuel rod was made of Nickel 200 and Inconel 625 materials. The fuel rod was connected to 10 KW DC power supply. The Inconel 625 material of the rod with an electrical resistance of 32.3 kO was used to generate heat inside the test-section. The heat energy dissipated from the Inconel tube due to the flow of electrical current flows into the working fluid across the rod at constant heat flux conditions. The DI water was employed as working fluid for this experimental investigation. The temperature and pressure readings for both smooth and rough regions of the fuel rod were recorded and compared later to find enhancement in heat transfer coefficient and increment in the pressure drops. Tests were conducted for Reynold's Numbers ranging from 10e4 to 10e5. Enhancement in heat transfer coefficient at all Re was recorded. The maximum heat transfer co-efficient enhancement recorded was 86% at Re = 4.18e5. It was also observed that the pressure drop and friction factor increased by 14.7% due to the increased surface roughness.

  10. Interspecies recombination between enterococci: genetic and phenotypic diversity of vancomycin-resistant transconjugants.

    PubMed

    McAshan, S K; Vergin, K L; Giovannoni, S J; Thaler, D S

    1999-01-01

    recipient and donor strains used in transconjugation experiments were different species. Sequence analysis was also used to consider the possibility that rRNA operons might be mobilized in conjugation, but no evidence for the transfer of rDNA operons was found. An apparent insertion sequence in E. faecium almost identical to IS 1485 and 57% sequence identity to IS 199 of Streptococcus mutans was found in the region of DNA transferred. The results imply new consequences of conjugative transfer and interspecies recombination. PMID:10432271

  11. Development of Species Sensitivity Distributions for Wildlife Using Interspecies Toxicity Correlation Models

    EPA Science Inventory

    Species sensitivity distributions (SSD) are cumulative distributions of chemical toxicity of multiple species and have had limited application in wildlife risk assessment because of relatively small datasets of wildlife toxicity values. Interspecies correlation estimation (ICE) m...

  12. ESTIMATION OF CHEMICAL TOXICITY TO WILDLIFE SPECIES USING INTERSPECIES CORRELATION MODELS

    EPA Science Inventory

    Ecological risks to wildlife are typically assessed using toxicity data for relataively few species and with limited understanding of differences in species sensitivity to contaminants. Empirical interspecies correlation models were derived from LD50 values for 49 wildlife speci...

  13. ESTIMATION OF AQUATIC SPECIES SENSITIVITY USING INTERSPECIES CORRELATION AND ACUTE TO CHRONIC TOXICITY MODELS

    EPA Science Inventory

    Abstract for presentation

    Estimation of aquatic species sensitivity using interspecies correlation and acute to chronic toxicity models

    Determining species sensitivity of aquatic organisms to contaminants is a critical component of criteria development and ecolog...

  14. INTER-SPECIES MODELS FOR ACUTE AQUATIC TOXICITY BASED ON MECHANISM OF ACTION

    EPA Science Inventory

    This presentation will provide interspecies QSARs for acute toxicity to 17 aquatic species, such as fish, snail, tadpole, hydrozoan, crustacean, insect larvae, and bacteria developed using 5,000 toxic effect results for approximately 2400 chemicals.

  15. Heat transfer effects in vertically emplaced high level nuclear waste container

    SciTech Connect

    Moujaes, S.F.; Lei, Y.M.

    1994-05-01

    Modeling free convection heat transfer in an cylindrical annular enclosure is still an active area of research and an important problem to be addressed in the high level nuclear waste repository. For the vertically emplaced waste container, the air gap which is between the container shell and the rock borehole, have an important role of dissipating heat to surrounding rack. These waste containers are vertically emplaced in the borehole 300 meters below ground, and in a horizontal grid of 30 {times} 8 meters apart. The borehole will be capped after the container emplacement. The expected initial heat generated is between 3--4.74 kW per container depending on the type of waste. The goal of this study is to use a computer simulation model to find the borehole wall, air-gap and the container outer wall temperature distributions.

  16. Murine somatic cell nuclear transfer using reprogrammed donor cells expressing male germ cell-specific genes.

    PubMed

    Kang, Hoin; Park, Jong Im; Roh, Sangho

    2016-01-01

    In vivo-matured mouse oocytes were enucleated, and a single murine embryonic fibroblast (control or reprogrammed by introducing extracts from murine testis tissue, which showed expression of male germ cell-specific genes) was injected into the cytoplasm of the oocytes. The rate of blastocyst development and expression levels of Oct-4, Eomes and Cdx-2 were not significantly different in both experimental groups. However, the expression levels of Nanog, Sox9 and Glut-1 were significantly increased when reprogrammed cells were used as donor nuclei. Increased expression of Nanog can be supportive of complete reprogramming of somatic cell nuclear transfer murine embryos. The present study suggested that donor cells expressing male germ cell-specific genes can be reconstructed and can develop into embryos with normal high expression of developmentally essential genes. PMID:26369430

  17. In vitro development of canine somatic cell nuclear transfer embryos in different culture media.

    PubMed

    Kim, Dong-Hoon; No, Jin-Gu; Choi, Mi-Kyung; Yeom, Dong-Hyeon; Kim, Dong-Kyo; Yang, Byoung-Chul; Yoo, Jae Gyu; Kim, Min Kyu; Kim, Hong-Tea

    2015-01-01

    The objective of the present study was to investigate the effects of three different culture media on the development of canine somatic cell nuclear transfer (SCNT) embryos. Canine cloned embryos were cultured in modified synthetic oviductal fluid (mSOF), porcine zygote medium-3 (PZM-3), or G1/G2 sequential media. Our results showed that the G1/G2 media yielded significantly higher morula and blastocyst development in canine SCNT embryos (26.1% and 7.8%, respectively) compared to PZM-3 (8.5% and 0%or mSOF (2.3% and 0%) media. In conclusion, this study suggests that blastocysts can be produced more efficiently using G1/G2 media to culture canine SCNT embryos. PMID:25549216

  18. Femtosecond laser based enucleation of porcine oocytes for somatic cell nuclear transfer

    NASA Astrophysics Data System (ADS)

    Kütemeyer, K.; Lucas-Hahn, A.; Petersen, B.; Hassel, P.; Lemme, E.; Niemann, H.; Heisterkamp, A.

    2009-07-01

    Cloning of several mammalian species has been achieved by somatic cell nuclear transfer (SCNT) in recent years. However, this method still results in very low efficiencies around 1% which originate from suboptimal culture conditions and highly invasive techniques for oocyte enucleation and injection of the donor cell using micromanipulators. In this paper, we present a new minimal invasive method for oocyte imaging and enucleation based on the application of femtosecond (fs) laser pulses. After imaging of the oocyte with multiphoton microscopy, ultrashort pulses are focused onto the metaphase plate of MII-oocytes in order to ablate the DNA molecules. We show that fs laser based enucleation of porcine oocytes completely inhibits the first mitotic cleavage after parthenogenetic activation while maintaining intact oocyte morphology in most cases. In contrast, control groups without previous irradiation of the metaphase plate are able to develop to the blastocyst stage. Further experiments have to clarify the suitability of fs laser based enucleated oocytes for SCNT.

  19. Modeling Electronic-Nuclear Interactions for Excitation Energy Transfer Processes in Light-Harvesting Complexes.

    PubMed

    Lee, Mi Kyung; Coker, David F

    2016-08-18

    An accurate approach for computing intermolecular and intrachromophore contributions to spectral densities to describe the electronic-nuclear interactions relevant for modeling excitation energy transfer processes in light harvesting systems is presented. The approach is based on molecular dynamics (MD) calculations of classical correlation functions of long-range contributions to excitation energy fluctuations and a separate harmonic analysis and single-point gradient quantum calculations for electron-intrachromophore vibrational couplings. A simple model is also presented that enables detailed analysis of the shortcomings of standard MD-based excitation energy fluctuation correlation function approaches. The method introduced here avoids these problems, and its reliability is demonstrated in accurate predictions for bacteriochlorophyll molecules in the Fenna-Matthews-Olson pigment-protein complex, where excellent agreement with experimental spectral densities is found. This efficient approach can provide instantaneous spectral densities for treating the influence of fluctuations in environmental dissipation on fast electronic relaxation. PMID:27472379

  20. In vitro development of canine somatic cell nuclear transfer embryos in different culture media

    PubMed Central

    No, Jin-Gu; Choi, Mi-Kyung; Yeom, Dong-Hyeon; Kim, Dong-Kyo; Yang, Byoung-Chul; Yoo, Jae Gyu; Kim, Min Kyu; Kim, Hong-Tea

    2015-01-01

    The objective of the present study was to investigate the effects of three different culture media on the development of canine somatic cell nuclear transfer (SCNT) embryos. Canine cloned embryos were cultured in modified synthetic oviductal fluid (mSOF), porcine zygote medium-3 (PZM-3), or G1/G2 sequential media. Our results showed that the G1/G2 media yielded significantly higher morula and blastocyst development in canine SCNT embryos (26.1% and 7.8%, respectively) compared to PZM-3 (8.5% and 0%) or mSOF (2.3% and 0%) media. In conclusion, this study suggests that blastocysts can be produced more efficiently using G1/G2 media to culture canine SCNT embryos. PMID:25549216

  1. Bioactive conformation of stromelysin inhibitors determined by transferred nuclear Overhauser effects.

    PubMed Central

    Gonnella, N C; Bohacek, R; Zhang, X; Kolossváry, I; Paris, C G; Melton, R; Winter, C; Hu, S I; Ganu, V

    1995-01-01

    The transferred nuclear Overhauser effect has been used to determine the biologically active conformations of two stromelysin inhibitors. Both inhibitors used in this study were hydroxamic acids generated via chemical synthesis. These structures, representing the conformation of each inhibitor bound to stromelysin, superimposed with excellent agreement. The study also provided information on the shape and orientation of the S2' and S1' pockets of the enzyme relative to thermolysin. Comparisons were made between stromelysin and thermolysin inhibitors to critically examine thermolysin as a template for stromelysin-inhibitor design. The enzyme-bound conformations of these stromelysin inhibitors were determined for use as a template in conformationally restricted drug design. Images Fig. 4 Fig. 5 Fig. 6 Fig. 7 PMID:7831311

  2. Live embryo imaging to follow cell cycle and chromosomes stability after nuclear transfer.

    PubMed

    Balbach, Sebastian T; Boiani, Michele

    2015-01-01

    Nuclear transfer (NT) into mouse oocytes yields a transcriptionally and functionally heterogeneous population of cloned embryos. Most studies of NT embryos consider only embryos at predefined key stages (e.g., morula or blastocyst), that is, after the bulk of reprogramming has taken place. These retrospective approaches are of limited use to elucidate mechanisms of reprogramming and to predict developmental success. Observing cloned embryo development using live embryo cinematography has the potential to reveal otherwise undetectable embryo features. However, light exposure necessary for live cell cinematography is highly toxic to cloned embryos. Here we describe a protocol for combined bright-field and fluorescence live-cell imaging of histone H2b-GFP expressing mouse embryos, to record cell divisions up to the blastocyst stage. This protocol, which can be adapted to observe other reporters such as Oct4-GFP or Nanog-GFP, allowed us to quantitatively analyze cleavage kinetics of cloned embryos. PMID:25287344

  3. Exploiting level anti-crossings for efficient and selective transfer of hyperpolarization in coupled nuclear spin systems.

    PubMed

    Pravdivtsev, Andrey N; Yurkovskaya, Alexandra V; Kaptein, Robert; Miesel, Karsten; Vieth, Hans-Martin; Ivanov, Konstantin L

    2013-09-21

    Spin hyperpolarization can be coherently transferred to other nuclei in field-cycling NMR experiments. At low magnetic fields spin polarization is redistributed in a strongly coupled network of spins. Polarization transfer is most efficient at fields where level anti-crossings (LACs) occur for the nuclear spin-states. A further condition is that field switching to the LAC positions is non-adiabatic in order to convert the starting population differences into spin coherences that cause time-dependent mixing of states. The power of this method has been demonstrated by studying transfer of photo-Chemically Induced Dynamic Nuclear Polarization (photo-CIDNP) in N-acetyl-tryptophan. We have investigated the magnetic field dependence and time dependence of coherent CIDNP transfer and directly assessed nuclear spin LACs by studying polarization transfer at specific field positions. The proposed approach based on LACs is not limited to CIDNP but is advantageous for enhancing NMR signals by spin order transfer from any type of hyper-polarized nuclei. PMID:23893009

  4. Deficiency of Genomic Reprogramming in Trophoblast Stem Cells Following Nuclear Transfer

    PubMed Central

    Watanabe, Hiroyuki; Fukuda, Atsushi; Kono, Tomohiro

    2015-01-01

    Abstract To examine the genomic reprogrammability of trophoblast stem (TS) cells using a nuclear transfer technique, we produced TS cloned embryos using five TS cell lines from three strains of mice (ICR, B6D2F1, and B6CBF1) as donors and observed developmental ability during preimplantation development. The developmental rates of the TS cloned embryos that developed to the two-cell, four- to eight-cell, morula, and blastocyst stages were 58–83%, 0–38.6%, 0–21.3%, and 0–15.9%, respectively, indicating that more than 50% of TS cloned embryos arrested at the two-cell stage. These TS cloned two-cell embryos were expressed low level of Dappa3 (also known as PGC7/Stella), indicating that zygotic gene activation (ZGA) was disrupted in these embryos. However, a small portion of the TS cloned embryos (0–15.9%) reached the blastocyst stage. In these TS cloned blastocysts, the numbers of trophectoderm (TE) and inner cell mass (ICM) cells were 31.9±4.6 and 12.1±3.0, respectively, which were not significantly different from those in the fertilized embryos. In addition, the gene expression analysis showed that Oct3/4, and Cdx2, which are ICM- and TE-specific marker genes, respectively, and Dppa3, and Hdac1, which are zygotic gene activation-related genes, were expressed in TS cloned blastocysts at the same levels as in the fertilized blastocysts. These results indicate that although TS cloned embryos are able to differentiate into ICM cells, the genomic reprogrammability of TS cells is very low following nuclear transfer. PMID:25826724

  5. Spent Nuclear Fuel Dry Transfer System Cold Demonstration Project Final Report

    SciTech Connect

    Christensen, Max R; McKinnon, M. A.

    1999-12-01

    The spent nuclear fuel dry transfer system (DTS) provides an interface between large and small casks and between storage-only and transportation casks. It permits decommissioning of reactor pools after shutdown and allows the use of large storage-only casks for temporary onsite storage of spent nuclear fuel irrespective of reactor or fuel handling limitations at a reactor site. A cold demonstration of the DTS prototype was initiated in August 1996 at the Idaho National Engineering and Environmental Laboratory (INEEL). The major components demonstrated included the fuel assembly handling subsystem, the shield plug/lid handling subsystem, the cask interface subsystem, the demonstration control subsystem, a support frame, and a closed circuit television and lighting system. The demonstration included a complete series of DTS operations from source cask receipt and opening through fuel transfer and closure of the receiving cask. The demonstration included both normal operations and recovery from off-normal events. It was designed to challenge the system to determine whether there were any activities that could be made to jeopardize the activities of another function or its safety. All known interlocks were challenged. The equipment ran smoothly and functioned as designed. A few "bugs" were corrected. Prior to completion of the demonstration testing, a number of DTS prototype systems were modified to apply lessons learned to date. Additional testing was performed to validate the modifications. In general, all the equipment worked exceptionally well. The demonstration also helped confirm cost estimates that had been made at several points in the development of the system.

  6. Production of human apolipoprotein(a) transgenic NIBS miniature pigs by somatic cell nuclear transfer

    PubMed Central

    Shimatsu, Yoshiki; Horii, Wataru; Nunoya, Tetsuo; Iwata, Akira; Fan, Jianglin; Ozawa, Masayuki

    2015-01-01

    Most cases of ischemic heart disease and stroke occur as a result of atherosclerosis. The purpose of this study was to produce a new Nippon Institute for Biological Science (NIBS) miniature pig model by somatic cell nuclear transfer (SCNT) for studying atherosclerosis. The human apolipoprotein(a) (apo(a)) genes were transfected into kidney epithelial cells derived from a male and a female piglet. Male cells were used as donors initially, and 275 embryos were transferred to surrogates. Three offspring were delivered, and the production efficiency was 1.1% (3/275). Serial female cells were injected into 937 enucleated oocytes. Eight offspring were delivered (production efficiency: 0.9%) from surrogates. One male and 2 female transgenic miniature pigs matured well. Lipoprotein(a) was found in the male and one of the female transgenic animals. These results demonstrate successful production of human apo(a) transgenic NIBS miniature pigs by SCNT. Our goal is to establish a human apo(a) transgenic NIBS miniature pig colony for studying atherosclerosis. PMID:26411321

  7. Production of human apolipoprotein(a) transgenic NIBS miniature pigs by somatic cell nuclear transfer.

    PubMed

    Shimatsu, Yoshiki; Horii, Wataru; Nunoya, Tetsuo; Iwata, Akira; Fan, Jianglin; Ozawa, Masayuki

    2016-01-01

    Most cases of ischemic heart disease and stroke occur as a result of atherosclerosis. The purpose of this study was to produce a new Nippon Institute for Biological Science (NIBS) miniature pig model by somatic cell nuclear transfer (SCNT) for studying atherosclerosis. The human apolipoprotein(a) (apo(a)) genes were transfected into kidney epithelial cells derived from a male and a female piglet. Male cells were used as donors initially, and 275 embryos were transferred to surrogates. Three offspring were delivered, and the production efficiency was 1.1% (3/275). Serial female cells were injected into 937 enucleated oocytes. Eight offspring were delivered (production efficiency: 0.9%) from surrogates. One male and 2 female transgenic miniature pigs matured well. Lipoprotein(a) was found in the male and one of the female transgenic animals. These results demonstrate successful production of human apo(a) transgenic NIBS miniature pigs by SCNT. Our goal is to establish a human apo(a) transgenic NIBS miniature pig colony for studying atherosclerosis. PMID:26411321

  8. Faddeev-type calculation of (d ,n ) transfer reactions in three-body nuclear systems

    NASA Astrophysics Data System (ADS)

    Deltuva, A.

    2015-12-01

    Exact Faddeev-type three-body equations are applied to the study of the proton transfer reactions (d ,n ) in the system consisting of a nuclear core and two nucleons. The integral equations for the three-body transition operators are solved in the momentum-space framework including the Coulomb interaction via the screening and renormalization method. For a weakly bound final nucleus the calculation of the (d ,n ) reaction is more demanding in terms of the screening radius as compared to the (d ,p ) reaction. Well-converged differential cross section results are obtained for 7Be (d ,n ) 8B, 12C (d ,n ) 13N, and 16O (d ,n ) 17$ reactions. A comparison with the corresponding (d ,p ) reactions is made. The calculations fail to reproduce the shape of the angular distribution for reactions on 12C but provide quite successful description for reactions on 16O, especially for the transfer to the 17F excited state 1 /2+ when using a nonlocal optical potential.

  9. Phenotypes of Aging Postovulatory Oocytes After Somatic Cell Nuclear Transfer in Mice.

    PubMed

    Lee, Ah Reum; Shimoike, Takashi; Wakayama, Teruhiko; Kishigami, Satoshi

    2016-06-01

    Oocytes rapidly lose their developmental potential after ovulation, termed postovulatory oocyte aging, and often exhibit characteristic phenotypes, such as cytofragmentation, abnormal spindle shapes, and chromosome misalignments. Here, we reconstructed mouse oocytes using somatic cell nuclear transfer (SCNT) to reveal the effect of somatic cell-derived nuclei on oocyte physiology during aging. Normal oocytes started undergoing cytofragmentation 24 hours after oocyte collection; however, this occurred earlier in SCNT oocytes and was more severe at 48 hours, suggesting that the transferred somatic cell nuclei affected oocyte physiology. We found no difference in the status of acetylated α-tubulin (Ac-Tub) and α-tubulin (Tub) between normal and SCNT aging oocytes, but unlike normal oocytes, aging SCNT oocytes did not have astral microtubules. Interestingly, aging SCNT oocytes displayed more severely scattered chromosomes or irregularly shaped spindles. Observations of the microfilaments showed that, in normal oocytes, there was a clear actin ring beneath the plasma membrane and condensed microfilaments around the spindle (the actin cap) at 0 hours, and the actin filaments started degenerating at 1 hour, becoming completely disrupted and distributed to the cytoplasm at 24 hours. By contrast, in SCNT oocytes, an actin cap formed around the transplanted nuclei within 1 hour of SCNT, which was still present at 24 hours. Thus, SCNT oocytes age in a similar but distinct way, suggesting that they not only contain nuclei with abnormal epigenetics but are also physiologically different. PMID:27253626

  10. Interspecies differences in metabolism of arsenic by cultured primary hepatocytes

    SciTech Connect

    Drobna, Zuzana; Walton, Felecia S.; Harmon, Anne W.; Thomas, David J.; Styblo, Miroslav

    2010-05-15

    Biomethylation is the major pathway for the metabolism of inorganic arsenic (iAs) in many mammalian species, including the human. However, significant interspecies differences have been reported in the rate of in vivo metabolism of iAs and in yields of iAs metabolites found in urine. Liver is considered the primary site for the methylation of iAs and arsenic (+3 oxidation state) methyltransferase (As3mt) is the key enzyme in this pathway. Thus, the As3mt-catalyzed methylation of iAs in the liver determines in part the rate and the pattern of iAs metabolism in various species. We examined kinetics and concentration-response patterns for iAs methylation by cultured primary hepatocytes derived from human, rat, mice, dog, rabbit, and rhesus monkey. Hepatocytes were exposed to [{sup 73}As]arsenite (iAs{sup III}; 0.3, 0.9, 3.0, 9.0 or 30 nmol As/mg protein) for 24 h and radiolabeled metabolites were analyzed in cells and culture media. Hepatocytes from all six species methylated iAs{sup III} to methylarsenic (MAs) and dimethylarsenic (DMAs). Notably, dog, rat and monkey hepatocytes were considerably more efficient methylators of iAs{sup III} than mouse, rabbit or human hepatocytes. The low efficiency of mouse, rabbit and human hepatocytes to methylate iAs{sup III} was associated with inhibition of DMAs production by moderate concentrations of iAs{sup III} and with retention of iAs and MAs in cells. No significant correlations were found between the rate of iAs methylation and the thioredoxin reductase activity or glutathione concentration, two factors that modulate the activity of recombinant As3mt. No associations between the rates of iAs methylation and As3mt protein structures were found for the six species examined. Immunoblot analyses indicate that the superior arsenic methylation capacities of dog, rat and monkey hepatocytes examined in this study may be associated with a higher As3mt expression. However, factors other than As3mt expression may also contribute to

  11. Transfer-induced fission in inverse kinematics: Impact on experimental and evaluated nuclear data bases

    NASA Astrophysics Data System (ADS)

    Farget, F.; Caamaño, M.; Ramos, D.; Rodrıguez-Tajes, C.; Schmidt, K.-H.; Audouin, L.; Benlliure, J.; Casarejos, E.; Clément, E.; Cortina, D.; Delaune, O.; Derkx, X.; Dijon, A.; Doré, D.; Fernández-Domınguez, B.; Gaudefroy, L.; Golabek, C.; Heinz, A.; Jurado, B.; Lemasson, A.; Paradela, C.; Roger, T.; Salsac, M. D.; Schmitt, C.

    2015-12-01

    Inverse kinematics is a new tool to study nuclear fission. Its main advantage is the possibility to measure with an unmatched resolution the atomic number of fission fragments, leading to new observables in the properties of fission-fragment distributions. In addition to the resolution improvement, the study of fission based on nuclear collisions in inverse kinematics beneficiates from a larger view with respect to the neutron-induced fission, as in a single experiment the number of fissioning systems and the excitation energy range are widden. With the use of spectrometers, mass and kinetic-energy distributions may now be investigated as a function of the proton and neutron number sharing. The production of fissioning nuclei in transfer reactions allows studying the isotopic yields of fission fragments as a function of the excitation energy. The higher excitation energy resulting in the fusion reaction leading to the compound nucleus 250Cf at an excitation energy of 45MeV is also presented. With the use of inverse kinematics, the charge polarisation of fragments at scission is now revealed with high precision, and it is shown that it cannot be neglected, even at higher excitation energies. In addition, the kinematical properties of the fragments inform on the deformation configuration at scission.

  12. Inheritance of mitochondrial DNA in serially recloned pigs by somatic cell nuclear transfer (SCNT)

    SciTech Connect

    Do, Minhwa; Jang, Won-Gu; Hwang, Jeong Hee; Jang, Hoon; Kim, Eun-Jung; Jeong, Eun-Jeong; Shim, Hosup; Hwang, Sung Soo; Oh, Keon Bong; Byun, Sung June; Kim, Jin-Hoi; Lee, Jeong Woong

    2012-08-10

    Highlights: Black-Right-Pointing-Pointer We success serial SCNT through the third generation using pig fibroblasts. Black-Right-Pointing-Pointer Donor-specific mtDNA in the recloned pigs was detected. Black-Right-Pointing-Pointer SCNT affect mtDNA mounts. -- Abstract: Somatic cell nuclear transfer (SCNT) has been established for the transmission of specific nuclear DNA. However, the fate of donor mitochondrial DNA (mtDNA) remains unclear. Here, we examined the fate of donor mtDNA in recloned pigs through third generations. Fibroblasts of recloned pigs were obtained from offspring of each generation produced by fusion of cultured fibroblasts from a Minnesota miniature pig (MMP) into enucleated oocytes of a Landrace pig. The D-loop regions from the mtDNA of donor and recipient differ at nucleotide sequence positions 16050 (A{yields}T), 16062 (T{yields}C), and 16135 (G{yields}A). In order to determine the fate of donor mtDNA in recloned pigs, we analyzed the D-loop region of the donor's mtDNA by allele-specific PCR (AS-PCR) and real-time PCR. Donor mtDNA was successfully detected in all recloned offspring (F1, F2, and F3). These results indicate that heteroplasmy that originate from donor and recipient mtDNA is maintained in recloned pigs, resulting from SCNT, unlike natural reproduction.

  13. Fate of centrosomes following somatic cell nuclear transfer (SCNT) in bovine oocytes.

    PubMed

    Dai, Yunping; Wang, Lili; Wang, Haiping; Liu, Ying; Li, Ning; Lyu, Qifeng; Keefe, David L; Albertini, David F; Liu, Lin

    2006-06-01

    Cloning mammalians by somatic cell nuclear transfer (SCNT) remains inefficient. A majority of clones produced by SCNT fail to develop properly and of those which do survive, some exhibit early aging, premature death, tumors, and other pathologies associated with aneuploidy. Alterations of centrosomes are linked to aberrant cell cycle progression, aneuploidy, and tumorigenesis in many cell types. It remains to be determined how centrosomes are remodeled in cloned bovine embryos. We show that abnormalities in either distribution and/or number of centrosomes were evident in approximately 50% of reconstructed embryos following SCNT. Moreover, centrosome abnormalities and failed 'pronuclear' migration which manifested during the first cell cycle coincided with errors in spindle morphogenesis, chromosome alignment, and cytokinesis. By contrast, nuclear mitotic apparatus protein (NuMA) exhibited normal expression patterns at metaphase spindle poles and in 'pronucleus' during interphase. The defects in centrosome remodeling and 'pronuclear' migration could lead to chromosome instability and developmental failures associated with embryo production by SCNT. Addressing these fundamental problems may enhance production of normal clones. PMID:16735544

  14. Multi-Scale-Structured Composite Coatings by Plasma-Transferred Arc for Nuclear Applications

    NASA Astrophysics Data System (ADS)

    Werry, A.; Chazelas, C.; Denoirjean, A.; Valette, S.; Vardelle, A.; Meillot, E.

    2016-01-01

    In nuclear plants, the replacement of hardfacing Stellite, a cobalt-based alloy, on parts of the piping system in connection with the reactor has been investigated since the late 60's. Various Fe-based or Ni-based alloys, Co-free or with a low content of Co, have been developed but with mechanical properties generally lower than that of Stellites. The 4th generation nuclear plants impose additional or more stringent requirements for hardfacing materials. Plasma-transferred arc (PTA) coatings of cobalt-free nickel-based alloys with the addition of sub-micrometric or micrometric alumina particles are thought to be a potential solution for tribological applications in the primary system of sodium-cooled fast reactors. In this study, PTA coatings of nickel-based alloys reinforced with alumina particles were deposited on 316L stainless steel substrates. Under the conditions of this study, the addition of alumina particles resulted in a refinement of coating microstructure and the improvement of their resistance to abrasive wear. However, it does not bring about any change in coating micro-hardness.

  15. Heat Transfer in Waste Glass Melts - Measurement and Implications for Nuclear Waste Vitrification

    NASA Astrophysics Data System (ADS)

    Wang, Chuan

    Thermal properties of waste glass melts, such as high temperature density and thermal conductivity, are relevant to heat transfer processes in nuclear waste vitrification. Experimental measurement techniques were developed and applied to four nuclear waste glasses representative of those currently projected for treatment of Hanford HLW and LAW streams to study heat flow mechanisms in nuclear waste vitrification. Density measurement results by Archimedes' method indicated that densities of the melts investigated varied considerably with composition and temperature. Thermal diffusivities of waste melts were determined at nominal melter operating temperatures using a temperature-wave technique. Thermal conductivities were obtained by combining diffusivity data with the experimentally-acquired densities of the melts and their known heat capacities. The experimental results display quite large positive dependences of conductivities on temperature for some samples and much weaker positive temperature dependences for others. More importantly, there is observed a big change in the slopes of the conductivities versus temperature as temperature is increased for two of the melts, but not for the other two. This behavior was interpreted in terms of the changing contributions of radiation and conduction with temperature and composition dependence of the absorption coefficient. Based on the obtained thermal conductivities, a simple model for a waste glass melter was set up, which was used to analyze the relative contributions of conduction and radiation individually and collectively to the overall heat flow and to investigate factors and conditions that influence the radiation contribution to heat flow. The modeling results showed that unlike the case at lower temperatures, the radiant energy flow through waste melts could be predominant compared with conduction at temperature of about 900 °C or higher. However, heat flow due to radiation was roughly equal to that from

  16. Finite-thrust optimization of interplanetary transfers of space vehicle with bimodal nuclear thermal propulsion

    NASA Astrophysics Data System (ADS)

    Kharytonov, Oleksii M.; Kiforenko, Boris M.

    2011-08-01

    The nuclear thermal rocket (NTR) propulsion is one of the leading promising technologies for primary space propulsion for manned exploration of the solar system due to its high specific impulse capability and sufficiently high thrust-to-weight ratio. Another benefit of NTR is its possible bimodal design, when nuclear reactor is used for generation of a jet thrust in a high-thrust mode and (with an appropriate power conversion system) as a source of electric power to supply the payload and the electric engines in a low-thrust mode. The model of the NTR thrust control was developed considering high-thrust NTR as a propulsion system of limited power and exhaust velocity. For the proposed model the control of the thrust value is accomplished by the regulation of reactor thermal power and propellant mass flow rate. The problem of joint optimization of the combination of high- and low-thrust arcs and the parameters of bimodal NTR (BNTR) propulsion system is considered for the interplanetary transfers. The interplanetary trajectory of the space vehicle is formed by the high-thrust NTR burns, which define planet-centric maneuvers and by the low-thrust heliocentric arcs where the nuclear electric propulsion (NEP) is used. The high-thrust arcs are analyzed using finite-thrust approach. The motion of the corresponding dynamical system is realized in three phase spaces concerning the departure planet-centric maneuver by means of high-thrust NTR propulsion, the low-thrust NEP heliocentric maneuver and the approach high-thrust NTR planet-centric maneuver. The phase coordinates are related at the time instants of the change of the phase spaces due to the relations between the space vehicle masses. The optimal control analysis is performed using Pontryagin's maximum principle. The numerical results are analyzed for Earth-Mars "sprint" transfer. The optimal values of the parameters that define the masses of NTR and NEP subsystems have been evaluated. It is shown that the low

  17. Epistemological considerations in the extrapolation of metabolic data from non-humans to humans. [Validity of interspecies extrapolation

    SciTech Connect

    Crawford, D.J.; Richmond, C.R.

    1980-01-01

    The rationale underlying interspecies extrapolation of metabolic data has been based primarily on pragmatic concerns. Little attention has been given to the extent to which such extrapolations have a firm epistemological basis. The strength of this approach for model-free (purely empirical) extrapolation and for extrapolation involving a variety of theoretical constructs is examined in this paper. An attempt is made to provide some understanding of the degree of confidence that can be placed in the extrapolation of metabolic data from one species to another. Published results for a wide variety of radionuclides are analyzed and the importance of these results to the field of nuclear medicine is explored. Problems inherent in the logic of extrapolation are then delineated in view of these historical data.

  18. Interspecies tunneling in one-dimensional Bose mixtures

    SciTech Connect

    Pflanzer, Anika C.; Zoellner, Sascha; Schmelcher, Peter

    2010-02-15

    We study the ground-state properties and quantum dynamics of few-boson mixtures with strong interspecies repulsion in one-dimensional traps. If one species localizes at the center, e.g., due to a very large mass compared to the other component, it represents an effective barrier for the latter, and the system can be mapped onto identical bosons in a double well. For weaker localization, the barrier atoms begin to respond to the light component, leading to an induced attraction between the mobile atoms that may even outweigh their bare intraspecies repulsion. To explain the resulting effects, we derive an effective Hubbard model for the lighter species accounting for the back action of the barrier in correction terms to the lattice parameters. Also the tunneling is drastically affected: by varying the degree of localization of the 'barrier' atoms, the dynamics of intrinsically noninteracting bosons can change from Rabi oscillations to effective pair tunneling. For identical fermions (or fermionized bosons), this leads to the tunneling of attractively bound pairs.

  19. Analysis of copy number variation using quantitative interspecies competitive PCR.

    PubMed

    Williams, Nigel M; Williams, Hywel; Majounie, Elisa; Norton, Nadine; Glaser, Beate; Morris, Huw R; Owen, Michael J; O'Donovan, Michael C

    2008-10-01

    Over recent years small submicroscopic DNA copy-number variants (CNVs) have been highlighted as an important source of variation in the human genome, human phenotypic diversity and disease susceptibility. Consequently, there is a pressing need for the development of methods that allow the efficient, accurate and cheap measurement of genomic copy number polymorphisms in clinical cohorts. We have developed a simple competitive PCR based method to determine DNA copy number which uses the entire genome of a single chimpanzee as a competitor thus eliminating the requirement for competitive sequences to be synthesized for each assay. This results in the requirement for only a single reference sample for all assays and dramatically increases the potential for large numbers of loci to be analysed in multiplex. In this study we establish proof of concept by accurately detecting previously characterized mutations at the PARK2 locus and then demonstrating the potential of quantitative interspecies competitive PCR (qicPCR) to accurately genotype CNVs in association studies by analysing chromosome 22q11 deletions in a sample of previously characterized patients and normal controls. PMID:18697816

  20. Inter-species interconnections in acid mine drainage microbial communities

    PubMed Central

    Comolli, Luis R.; Banfield, Jill F.

    2014-01-01

    Metagenomic studies are revolutionizing our understanding of microbes in the biosphere. They have uncovered numerous proteins of unknown function in tens of essentially unstudied lineages that lack cultivated representatives. Notably, few of these microorganisms have been visualized, and even fewer have been described ultra-structurally in their essentially intact, physiologically relevant states. Here, we present cryogenic transmission electron microscope (cryo-TEM) 2D images and 3D tomographic datasets for archaeal species from natural acid mine drainage (AMD) microbial communities. Ultrastructural findings indicate the importance of microbial interconnectedness via a range of mechanisms, including direct cytoplasmic bridges and pervasive pili. The data also suggest a variety of biological structures associated with cell-cell interfaces that lack explanation. Some may play roles in inter-species interactions. Interdependences amongst the archaea may have confounded prior isolation efforts. Overall, the findings underline knowledge gaps related to archaeal cell components and highlight the likely importance of co-evolution in shaping microbial lineages. PMID:25120533

  1. PRIMATES AND PRIMATOLOGISTS: SOCIAL CONTEXTS FOR INTERSPECIES PATHOGEN TRANSMISSION

    PubMed Central

    Engel, GA; Jones-Engel, L

    2011-01-01

    Humans and nonhuman primates (NHP) interact in a variety of contexts. The frequency, duration and intensity of interspecies interaction influence the likelihood that contact results in cross-species transmission of infectious agents. Here we present results of a cross-sectional survey of attendees at a national conference of primatologists, characterizing their occupational exposures to NHP. Of 116 individuals who participated in the study, 68.1% reported having worked with NHP in a field setting, 68.1% in a laboratory setting and 24.1% at a zoo or animal sanctuary. Most subjects (N=98, 84.5%) reported having worked with multiple NHP taxa, including 46 (39.7%) who had worked with more than 5 distinct taxa. Sixty-nine subjects (59.5%) recalled having been scratched by a NHP and 48 (41.1%) had been bitten; 32 subjects reporting being bitten more than once. Eleven subjects (9.5%) reported having been injured by a needle containing NHP tissue or body fluids. We conclude that primatologists are at high risk for exposure to NHP-borne infectious agents. Furthermore, primatologists’ varied occupational activities often bring them into contact with multiple NHP species in diverse contexts and geographic areas, over extended periods of time, making them a unique population with respect to zoonotic and anthropozoonotic disease risk. PMID:21932331

  2. Interspecies Interaction between Pseudomonas aeruginosa and Other Microorganisms

    PubMed Central

    Tashiro, Yosuke; Yawata, Yutaka; Toyofuku, Masanori; Uchiyama, Hiroo; Nomura, Nobuhiko

    2013-01-01

    Microbes interact with each other in multicellular communities and this interaction enables certain microorganisms to survive in various environments. Pseudomonas aeruginosa is a highly adaptable bacterium that ubiquitously inhabits diverse environments including soil, marine habitats, plants and animals. Behind this adaptivity, P. aeruginosa has abilities not only to outcompete others but also to communicate with each other to develop a multispecies community. In this review, we focus on how P. aeruginosa interacts with other microorganisms. P. aeruginosa secretes antimicrobial chemicals to compete and signal molecules to cooperate with other organisms. In other cases, it directly conveys antimicrobial enzymes to other bacteria using the Type VI secretion system (T6SS) or membrane vesicles (MVs). Quorum sensing is a central regulatory system used to exert their ability including antimicrobial effects and cooperation with other microbes. At least three quorum sensing systems are found in P. aeruginosa, Las, Rhl and Pseudomonas quinolone signal (PQS) systems. These quorum-sensing systems control the synthesis of extracellular antimicrobial chemicals as well as interaction with other organisms via T6SS or MVs. In addition, we explain the potential of microbial interaction analysis using several micro devices, which would bring fresh sensitivity to the study of interspecies interaction between P. aeruginosa and other organisms. PMID:23363620

  3. Coupled quantum-classical method for long range charge transfer: relevance of the nuclear motion to the quantum electron dynamics

    NASA Astrophysics Data System (ADS)

    da Silva, Robson; Hoff, Diego A.; Rego, Luis G. C.

    2015-04-01

    Charge and excitonic-energy transfer phenomena are fundamental for energy conversion in solar cells as well as artificial photosynthesis. Currently, much interest is being paid to light-harvesting and energy transduction processes in supramolecular structures, where nuclear dynamics has a major influence on electronic quantum dynamics. For this reason, the simulation of long range electron transfer in supramolecular structures, under environmental conditions described within an atomistic framework, has been a difficult problem to study. This work describes a coupled quantum mechanics/molecular mechanics method that aims at describing long range charge transfer processes in supramolecular systems, taking into account the atomistic details of large molecular structures, the underlying nuclear motion, and environmental effects. The method is applied to investigate the relevance of electron-nuclei interaction on the mechanisms for photo-induced electron-hole pair separation in dye-sensitized interfaces as well as electronic dynamics in molecular structures.

  4. Production of transgenic dairy goat expressing human α-lactalbumin by somatic cell nuclear transfer.

    PubMed

    Feng, Xiujing; Cao, Shaoxian; Wang, Huili; Meng, Chunhua; Li, Jingxin; Jiang, Jin; Qian, Yong; Su, Lei; He, Qiang; Zhang, Qingxiao

    2015-02-01

    Production of human α-lactalbumin (hα-LA) transgenic cloned dairy goats has great potential in improving the nutritional value and perhaps increasing the yield of dairy goat milk. Here, a mammary-specific expression vector 5A, harboring goat β-lactoglobulin (βLG) promoter, the hα-LA gene, neo(r) and EGFP dual markers, was constructed. Then, it was effectively transfected into goat mammary epithelial cells (GMECs) and the expression of hα-LA was investigated. Both the hα-LA transcript and protein were detected in the transfected GMECs after the induction of hormonal signals. In addition, the 5A vector was introduced into dairy goat fetal fibroblasts (transfection efficiency ≈60-70%) to prepare competent transgenic donor cells. A total of 121 transgenic fibroblast clones were isolated by 96-well cell culture plates and screened with nested-PCR amplification and EGFP fluorescence. After being frozen for 8 months, the transgenic cells still showed high viabilities, verifying their ability as donor cells. Dairy goat cloned embryos were produced from these hα-LA transgenic donor cells by somatic cell nuclear transfer (SCNT), and the rates of fusion, cleavage, and the development to blastocyst stages were 81.8, 84.4, and 20.0%, respectively. A total of 726 reconstructed embryos derived from the transgenic cells were transferred to 74 recipients and pregnancy was confirmed at 90 days in 12 goats. Of six female kids born, two carried hα-LA and the hα-LA protein was detected in their milk. This study provides an effective system to prepare SCNT donor cells and transgenic animals for human recombinant proteins. PMID:25139669

  5. Effects of Histone Deacetylase Inhibitor Oxamflatin on In Vitro Porcine Somatic Cell Nuclear Transfer Embryos

    PubMed Central

    Hou, Liming; Ma, Fanhua; Yang, Jinzeng; Riaz, Hasan; Wang, Yongliang; Wu, Wangjun; Xia, Xiaoliang; Ma, Zhiyuan; Zhou, Ying; Zhang, Lin; Ying, Wenqin; Xu, Dequan; Zuo, Bo; Ren, Zhuqing

    2014-01-01

    Abstract Low cloning efficiency is considered to be caused by the incomplete or aberrant epigenetic reprogramming of differentiated donor cells in somatic cell nuclear transfer (SCNT) embryos. Oxamflatin, a novel class of histone deacetylase inhibitor (HDACi), has been found to improve the in vitro and full-term developmental potential of SCNT embryos. In the present study, we studied the effects of oxamflatin treatment on in vitro porcine SCNT embryos. Our results indicated that the rate of in vitro blastocyst formation of SCNT embryos treated with 1 μM oxamflatin for 15 h postactivation was significantly higher than all other treatments. Treatment of oxamflatin decreased the relative histone deacetylase (HDAC) activity in cloned embryos and resulted in hyperacetylation levels of histone H3 at lysine 9 (AcH3K9) and histone H4 at lysine 5 (AcH4K5) at pronuclear, two-cell, and four-cell stages partly through downregulating HDAC1. The suppression of HDAC6 through oxamflatin increased the nonhistone acetylation level of α-tubulin during the mitotic cell cycle of early SCNT embryos. In addition, we demonstrated that oxamflatin downregulated DNA methyltransferase 1 (DNMT1) expression and global DNA methylation level (5-methylcytosine) in two-cell-stage porcine SCNT embryos. The pluripotency-related gene POU5F1 was found to be upregulated in the oxamflatin-treated group with a decreased DNA methylation tendency in its promoter regions. Treatment of oxamflatin did not change the locus-specific DNA methylation levels of Sus scrofa heterochromatic satellite DNA sequences at the blastocyst stage. Meanwhile, our findings suggest that treatment with HDACi may contribute to maintaining the stable status of cytoskeleton-associated elements, such as acetylated α-tubulin, which may be the crucial determinants of donor nuclear reprogramming in early SCNT embryos. In summary, oxamflatin treatment improves the developmental potential of porcine SCNT embryos in vitro. PMID

  6. Production of myostatin-targeted goat by nuclear transfer from cultured adult somatic cells.

    PubMed

    Zhou, Zheng-Rong; Zhong, Bu-Shuai; Jia, Ruo-Xin; Wan, Yong-Jie; Zhang, Yan-Li; Fan, Yi-Xuan; Wang, Li-Zhong; You, Ji-Hao; Wang, Zi-Yu; Wang, Feng

    2013-01-15

    Myostatin, a member of the transforming growth factor-β family, acts as a negative regulator of skeletal muscle mass. In this study, myostatin-targeted caprine fibroblasts were obtained and subjected to SCNT to determine whether myostatin-knockout goats could be created. Fibroblasts from a 2-mo-old goat were transfected with a myostatin-targeted vector to prepare transgenic donor cells for nuclear transfer. After serum-starvation (for synchronization of the cell cycle), the percentage of transgenic fibroblasts in the G(0)/G(1) phase increased (66.2% vs. 82.9%; P < 0.05) compared with that in the control group, whereas the apoptosis rate and mitochondrial membrane potential were unaffected (P > 0.05). There were no significant differences between in vivo- and in vitro-matured oocytes as recipient cytoplasts for rates of fusion (86.5% vs. 78.4%), pregnancy (21.6% vs. 16.7%), or kidding (2.7% vs. 0%). One female kid from an in vivo-matured oocyte was born, but died a few hours later. Microsatellite analysis and polymerase chain reaction identification confirmed that this kid was genetically identical to the donor cells. Based on Western blot analysis, myostatin of the cloned kid was not expressed compared with that of nontransgenic kids. In conclusion, SCNT using myostatin-targeted 2-mo-old goat fibroblasts as donors has potential as a method for producing myostatin-targeted goats. PMID:23174778

  7. Functional enucleation of porcine oocytes for somatic cell nuclear transfer using femtosecond laser pulses

    NASA Astrophysics Data System (ADS)

    Kuetemeyer, K.; Lucas-Hahn, A.; Petersen, B.; Hassel, P.; Lemme, E.; Niemann, H.; Heisterkamp, A.

    2010-02-01

    Cloning of several mammalian species has been achieved by somatic cell nuclear transfer over the last decade. However, this method still results in very low efficiencies originating from biological and technical aspects. The highly-invasive mechanical enucleation belongs to the technical aspects and requires considerable micromanipulation skill. In this paper, we present a novel non-invasive method for combined oocyte imaging and automated functional enucleation using femtosecond (fs) laser pulses. After three-dimensional imaging of Hoechst-labeled porcine oocytes by multiphoton microscopy, our self-developed software automatically determined the metaphase plate position and shape. Subsequent irradiation of this volume with the very same laser at higher pulse energies in the low-density-plasma regime was used for metaphase plate ablation. We show that functional fs laser-based enucleation of porcine oocytes completely inhibited further embryonic development while maintaining intact oocyte morphology. In contrast, non-irradiated oocytes were able to develop to the blastocyst stage without significant differences to control oocytes. Our results indicate that fs laser systems offer great potential for oocyte imaging and enucleation as a fast, easy to use and reliable tool which may improve the efficiency of somatic cell clone production.

  8. The ability of mouse nuclear transfer embryonic stem cells to differentiate into primordial germ cells

    PubMed Central

    Mansouri, Vahid; Salehi, Mohammad; Nourozian, Mohsen; Fadaei, Fatemeh; Farahani, Reza Mastery; Piryaei, Abbas; Delbari, Ali

    2015-01-01

    Nuclear transfer embryonic stem cells (ntESCs) show stem cell characteristics such as pluripotency but cause no immunological disorders. Although ntESCs are able to differentiate into somatic cells, the ability of ntESCs to differentiate into primordial germ cells (PGCs) has not been examined. In this work, we examined the capacity of mouse ntESCs to differentiate into PGCs in vitro. ntESCs aggregated to form embryoid bodies (EB) in EB culture medium supplemented with bone morphogenetic protein 4(BMP4) as the differentiation factor. The expression level of specific PGC genes was compared at days 4 and 8 using real time PCR. Flow cytometry and immunocytochemical staining were used to detect Mvh as a specific PGC marker. ntESCs expressed particular genes related to different stages of PGC development. Flow cytometry and immunocytochemical staining confirmed the presence of Mvh protein in a small number of cells. There were significant differences between cells that differentiated into PGCs in the group treated with Bmp4 compared to non-treated cells. These findings indicate that ntESCs can differentiate into putative PGCs. Improvement of ntESC differentiation into PGCs may be a reliable means of producing mature germ cells. PMID:26273226

  9. Lymphoid lineage differentiation potential of mouse nuclear transfer embryonic stem cells.

    PubMed

    Eslami-Arshaghi, Tarlan; Salehi, Mohammad; Soleimani, Masoud; Gholipourmalekabadi, Mazaher; Mossahebi-Mohammadi, Majid; Ardeshirylajimi, Abdolreza; Rajabi, Hoda

    2015-09-01

    Stem cells therapy is considered as an efficient strategy for the treatment of some diseases. Nevertheless, some obstacles such as probability of rejection by the immune system limit applications of this strategy. Therefore, several efforts have been made to overcome this among which using the induced pluripotent stem cells (iPSCs) and nuclear transfer embryonic stem cell (nt-ESCs) are the most efficient strategies. The objective of this study was to evaluate the differentiation potential of the nt-ESCs to lymphoid lineage in the presence of IL-7, IL-3, FLT3-ligand and TPO growth factors in vitro. To this end, the nt-ESCs cells were prepared and treated with aforementioned growth factors for 7 and 14 days. Then, the cells were examined for expression of lymphoid markers (CD3, CD25, CD127 and CD19) by quantitative PCR (q-PCR) and flow cytometry. An increased expression of CD19 and CD25 markers was observed in the treated cells compared with the negative control samples by day 7. After 14 days, the expression level of all the tested CD markers significantly increased in the treated groups in comparison with the control. The current study reveals the potential of the nt-ESCs in differentiation to lymphoid lineage in the presence of defined growth factors. PMID:26239678

  10. TEMP: A finite line heat transfer code for geologic repositories for nuclear waste

    SciTech Connect

    Wurm, K.J.; Bloom, S.G.; Atterbury, W.G.; Hetteberg, J.R.

    1987-10-01

    TEMP is a FORTRAN computer code for calculating temperatures in a geologic repository for nuclear waste. It will calculate the incremental temperature contributed by a single heat source, by an infinite array of heat sources, or by heat sources geometrically arranged in a finite array. In the finite array geometry, different types of heat sources can be placed in different regions at different times to more closely approximate the emplacement of waste in a repository. TEMP uses a semi-analytical technique for solving the equation for a heat producing finite length line source in an infinite and isotropic medium. Temperature contributions from individual heat sources are superimposed to determine the temperature at a specific location and time in a repository of multiple heat sources. Thermal conductivity of the geologic medium can be a function of temperature, and, when it is, an approximation is made for the temperature dependence of thermal diffusivity. This report derives the equations solved by TEMP and documents its accuracy by comparing its results to known analytical solutions and to the finite-difference and finite-element heat transfer codes HEATING5, HEATING6, THAC-SIP-3D, SPECTROM-41, and STEALTH-2D. The temperature results from TEMP are shown to be very accurate when compared to the analytical solutions and to the results from the finite-difference and finite-element codes. 8 refs., 97 figs., 39 tabs.

  11. Transcriptomic Features of Bovine Blastocysts Derived by Somatic Cell Nuclear Transfer

    PubMed Central

    Min, Byungkuk; Cho, Sunwha; Park, Jung Sun; Lee, Yun-Gyeong; Kim, Namshin; Kang, Yong-Kook

    2015-01-01

    Reprogramming incompletely occurs in most somatic cell nuclear transfer (SCNT) embryos, which results in misregulation of developmentally important genes and subsequent embryonic malfunction and lethality. Here we examined transcriptome profiles in single bovine blastocysts derived by in vitro fertilization (IVF) and SCNT. Different types of donor cells, cumulus cell and ear-skin fibroblast, were used to derive cSCNT and fSCNT blastocysts, respectively. SCNT blastocysts expressed 13,606 genes on average, similar to IVF (13,542). Correlation analysis found that both cSCNT and fSCNT blastocyst groups had transcriptomic features distinctive from the IVF group, with the cSCNT transcriptomes closer to the IVF ones than the fSCNT. Gene expression analysis identified 56 underrepresented and 78 overrepresented differentially expressed genes in both SCNT groups. A 400-kb locus harboring zinc-finger protein family genes in chromosome 18 were found coordinately down-regulated in fSCNT blastocysts, showing a feature of reprogramming-resistant regions. Probing into different categories of genes important for blastocyst development revealed that genes involved in trophectoderm development frequently were underrepresented, and those encoding epigenetic modifiers tended to be overrepresented in SCNT blastocysts. Our effort to identify reprogramming-resistant, differentially expressed genes can help map reprogramming error-prone loci onto the genome and elucidate how to handle the stochastic events of reprogramming to improve cloning efficiency. PMID:26342001

  12. Establishment, differentiation, electroporation, viral transduction, and nuclear transfer of bovine and porcine mesenchymal stem cells.

    PubMed

    Colleoni, S; Donofrio, G; Lagutina, I; Duchi, R; Galli, C; Lazzari, G

    2005-01-01

    Mesenchymal stem cells (MSCs) reside in the bone marrow and have the potential for multilineage differentiation, into bone, cartilage, and fat, for example. In this study, bovine and porcine MSCs were isolated, cultured to determine their replication ability, and differentiated with osteogenic medium and 5-azacytine. Both bovine and porcine undifferentiated MSCs were electroporated and virally transduced to test the efficiency of genetic modification and the maintainance of differentiation ability thereafter. Nuclear transfer experiments were carried out with bovine and porcine MSCs, both at the undifferentiated state and following differentiation. Our results indicate that bovine and porcine MSCs have limited lifespans in vitro--approximately 50 population doublings. They can be efficiently differentiated and characterized along the osteogenic lineage by morphology, alkaline phosphatase, Von Kossa, oil red stainings, and RT-PCR. Electroporation and selection induce high levels of EGFP expression in porcine but not in bovine MSCs. Following genetic modification, MSCs retain their pluridifferentiation ability as parental cells. Cloned embryos derived from bovine and porcine undifferentiated MSCs and their derivatives along the osteogenic lineage give rise to consistently high preimplantation development comparable to adult fibroblasts. PMID:16176125

  13. Abnormal dynamic changes in β-tubulin in somatic nuclear transfer cloned mouse embryos.

    PubMed

    Shen, Jingling; Wang, Zhendong; Shen, Xinghui; Zheng, Zhong; Zhang, Qinghua; Feng, Xiuqing; Hu, Lili; Lei, Lei

    2015-02-01

    The efficiency of somatic cell nuclear transfer (SCNT) cloning remains low, thus limiting the applications of this technique. In this study, we used immunochemistry and confocal microscopy to detect the microtubule component, β-tubulin, in SCNT, parthenogenetic (PA), and intracytoplasmic sperm injection (ICSI) embryos before the first mitotic division. β-Tubulin is the component subunit of microtubule, which plays critical roles in regulating localization of cellular organelles, and the growth, maturation and fertilization of oocytes. Our results demonstrated similar changes of spindle patterns in PA and ICSI embryos. The second meiotic division resumed 1 h post-treatment, and the cytoplasmic asters (CAs) disappeared. After about 4-6 h of treatment, pronuclei formed with the midbodies connecting each other. Meanwhile, the CAs reappeared and a microtubule network developed in the cytoplasm. However, SCNT embryos showed abnormal multipolar spindles, and the pseudopronuclei that contained many nucleoli existed after 6 h of SrCl2 activation. Enucleated oocytes alone did not form spindle-like structures when they were artificially activated for 6 h, indicating that somatic cell chromosomes might be necessary for spindle formation in SCNT embryos. These results demonstrated abnormal changes of β-tubulin in mouse SCNT embryos, compared with PA and ICSI embryos. PMID:24345634

  14. Transcriptomic Features of Bovine Blastocysts Derived by Somatic Cell Nuclear Transfer.

    PubMed

    Min, Byungkuk; Cho, Sunwha; Park, Jung Sun; Lee, Yun-Gyeong; Kim, Namshin; Kang, Yong-Kook

    2015-12-01

    Reprogramming incompletely occurs in most somatic cell nuclear transfer (SCNT) embryos, which results in misregulation of developmentally important genes and subsequent embryonic malfunction and lethality. Here we examined transcriptome profiles in single bovine blastocysts derived by in vitro fertilization (IVF) and SCNT. Different types of donor cells, cumulus cell and ear-skin fibroblast, were used to derive cSCNT and fSCNT blastocysts, respectively. SCNT blastocysts expressed 13,606 genes on average, similar to IVF (13,542). Correlation analysis found that both cSCNT and fSCNT blastocyst groups had transcriptomic features distinctive from the IVF group, with the cSCNT transcriptomes closer to the IVF ones than the fSCNT. Gene expression analysis identified 56 underrepresented and 78 overrepresented differentially expressed genes in both SCNT groups. A 400-kb locus harboring zinc-finger protein family genes in chromosome 18 were found coordinately down-regulated in fSCNT blastocysts, showing a feature of reprogramming-resistant regions. Probing into different categories of genes important for blastocyst development revealed that genes involved in trophectoderm development frequently were underrepresented, and those encoding epigenetic modifiers tended to be overrepresented in SCNT blastocysts. Our effort to identify reprogramming-resistant, differentially expressed genes can help map reprogramming error-prone loci onto the genome and elucidate how to handle the stochastic events of reprogramming to improve cloning efficiency. PMID:26342001

  15. TRANSFER OF EXCESS NUCLEAR MATERIAL FROM LOS ALAMOS TO SAVANNAH RIVER SITE FOR LONG-TERM DISPOSITION

    SciTech Connect

    C. W. HOTH; L. A. FOSTER; T. F YARBRO

    2001-06-01

    Los Alamos National Laboratory is preparing excess nuclear material for shipment to Savannah River Site (SRS) for final disposition. Prior to shipment the nuclear material will be stabilized and packaged to meet strict criteria. The criterion that must be met include: (1) the DOE stabilization, packaging and storage requirements for plutonium bearing materials, DOE-STD-3013, (2) shipping container packaging requirements, (3) SRS packaging and storage criteria, and (4) DOE Material Disposition criteria for either immobilization or MOX reactor fuel. Another issue in preparing for this transfer is the DOE certification of shipping containers and the availability of shipping containers. This transfer of the nuclear material is fully supported by the EM, DP and NN Sections of the DOE, as well as, by LANL and SRS, yet a strong collaboration is needed to meet all established requirements relating to stabilization, packaging, shipment, storage and final disposition. This paper will present the overall objectives, the issues and the planned strategy to accomplish this nuclear material transfer.

  16. Operational safety enhancement of Soviet-designed nuclear reactors via development of nuclear power plant simulators and transfer of related technology

    SciTech Connect

    Kohut, P.; Epel, L.G.; Tutu, N.K.

    1998-08-01

    The US Department of Energy (DOE), under the US government`s International Nuclear Safety Program (INSP), is implementing a program of developing and providing simulators for many of the Russian and Ukrainian Nuclear Power Plants (NPPs). Pacific Northwest National Laboratory (PNNL) and Brookhaven National Laboratory (BNL) manage and provide technical oversight of the various INSP simulator projects for DOE. The program also includes a simulator technology transfer process to simulator design organizations in Russia and Ukraine. Training programs, installation of new simulators, and enhancements in existing simulators are viewed as providing a relatively fast and cost-effective technology transfer that will result in measurable improvement in the safety culture and operation of NPPs. A review of this program, its present status, and its accomplishments are provided in this paper.

  17. Inter-species entanglement of Bose–Bose mixtures trapped in optical lattices

    NASA Astrophysics Data System (ADS)

    (王 巍, Wei Wang; Penna, Vittorio; Capogrosso-Sansone, Barbara

    2016-06-01

    In the present work we discuss inter-species entanglement in Bose–Bose mixtures trapped in optical lattices. This work is motivated by the observation that, in the presence of a second component, the MI lobe shifts differently on the hole- and particle-side with respect to the Mott lobe of the single species system (Guglielmino et al 2010 Phys. Rev. A 82 021601; Capogrosso-Sansone et al 2011 Laser Phys. 21 1443). We use perturbation theory, formulated in a Hilbert space decomposed by means of lattice symmetries, in order to show that the nonuniform shift of the Mott lobe is a manifestation of inter-species entanglement which differs in the lowest excited states to remove and add a particle. Our results indicate that inter-species entanglement in mixtures can provide a new perspective in understanding quantum phase transitions. To validate our approach, we compare our results from perturbation theory with quantum Monte Carlo simulations.

  18. Nuclear transfer of synchronized african wild cat somatic cells into enucleated domestic cat oocytes.

    PubMed

    Gómez, Martha C; Jenkins, Jill A; Giraldo, Angelica; Harris, Rebecca F; King, Amy; Dresser, Betsy L; Pope, Charles Earle

    2003-09-01

    The African wild cat is one of the smallest wild cats and its future is threatened by hybridization with domestic cats. Nuclear transfer, a valuable tool for retaining genetic variability, offers the possibility of species continuation rather than extinction. The aim of this study was to investigate the ability of somatic cell nuclei of the African wild cat (AWC) to dedifferentiate within domestic cat (DSH) cytoplasts and to support early development after nuclear transplantation. In experiment 1, distributions of AWC and DSH fibroblasts in each cell-cycle phase were assessed by flow cytometry using cells cultured to confluency and disaggregated with pronase, trypsin, or mechanical separation. Trypsin (89.0%) and pronase (93.0%) yielded higher proportions of AWC nuclei in the G0/G1 phase than mechanical separation (82.0%). In contrast, mechanical separation yielded higher percentages of DSH nuclei in the G0/G1 phase (86.6%) than pronase (79.7%) or trypsin (74.2%) treatments. In both species, pronase induced less DNA damage than trypsin. In experiment 2, the effects of serum starvation, culture to confluency, and exposure to roscovitine on the distribution of AWC and DSH fibroblasts in various phases of the cell cycle were determined. Flow cytometry analyses revealed that the dynamics of the cell cycle varied as culture conditions were modified. Specifically, a higher percentage of AWC and DSH nuclei were in the G0/G1 phase after cells were serum starved (83% vs. 96%) than were present in cycling cells (50% vs. 64%), after contact inhibition (61% vs. 88%), or after roscovitine (56% vs. 84%) treatment, respectively. In experiment 3, we evaluated the effects of cell synchronization and oocyte maturation (in vivo vs. in vitro) on the reconstruction and development of AWC-DSH- and DSH-DSH-cloned embryos. The method of cell synchronization did not affect the fusion and cleavage rate because only a slightly higher percentage of fused couplets cleaved when donor nuclei

  19. Nuclear transfer of synchronized African wild cat somatic cells into enucleated domestic cat oocytes

    USGS Publications Warehouse

    Gomez, M.C.; Jenkins, J.A.; Giraldo, A.; Harris, R.F.; King, A.; Dresser, B.L.; Pope, C.E.

    2003-01-01

    The African wild cat is one of the smallest wild cats and its future is threatened by hybridization with domestic cats. Nuclear transfer, a valuable tool for retaining genetic variability, offers the possibility of species continuation rather than extinction. The aim of this study was to investigate the ability of somatic cell nuclei of the African wild cat (AWC) to dedifferentiate within domestic cat (DSH) cytoplasts and to support early development after nuclear transplantation. In experiment 1, distributions of AWC and DSH fibroblasts in each cell-cycle phase were assessed by flow cytometry using cells cultured to confluency and disaggregated with pronase, trypsin, or mechanical separation. Trypsin (89.0%) and pronase (93.0%) yielded higher proportions of AWC nuclei in the G0/G1 phase than mechanical separation (82.0%). In contrast, mechanical separation yielded higher percentages of DSH nuclei in the G0/G1 phase (86.6%) than pronase (79.7%) or trypsin (74.2%) treatments. In both species, pronase induced less DNA damage than trypsin. In experiment 2, the effects of serum starvation, culture to confluency, and exposure to roscovitine on the distribution of AWC and DSH fibroblasts in various phases of the cell cycle were determined. Flow cytometry analyses revealed that the dynamics of the cell cycle varied as culture conditions were modified. Specifically, a higher percentage of AWC and DSH nuclei were in the G0/G1 phase after cells were serum starved (83% vs. 96%) than were present in cycling cells (50% vs. 64%), after contact inhibition (61% vs. 88%), or after roscovitine (56% vs. 84%) treatment, respectively. In experiment 3, we evaluated the effects of cell synchronization and oocyte maturation (in vivo vs. in vitro) on the reconstruction and development of AWC-DSH- and DSH-DSH-cloned embryos. The method of cell synchronization did not affect the fusion and cleavage rate because only a slightly higher percentage of fused couplets cleaved when donor nuclei

  20. Protein profiles of bovine placenta derived from somatic cell nuclear transfer.

    PubMed

    Kim, Hong Rye; Kang, Jae Ku; Yoon, Jong Taek; Seong, Hwan Hoo; Jung, Jin Kwan; Lee, Hong Mie; Sik Park, Chang; Jin, Dong Il

    2005-11-01

    Practical application of animal cloning by somatic cell nuclear transfer (SCNT) has been hampered by an extremely low success rate. To address whether placental dysfunction in SCNT causes fetal loss during pregnancy, we have used a global proteomics approach using 2-DE and MS to analyze the differential protein patterns of three placentae from the afterbirth of cases of postnatal death, derived from SCNT of Korean Native cattle, and three normal placentae obtained from the afterbirth of fetuses derived from artificial insemination. Proteins within a pI range of 4.0-7.0 and 6.0-9.0 were analyzed separately by 2-DE in triplicate. A total of approximately 2000 spots were detected in placental 2-DE gels stained with CBB. In the comparison of normal and SCNT samples, 60 spots were identified as differentially expressed proteins, of which 33 spots were up-regulated proteins in SCNT placentae, while 27 spots were down-regulated proteins. Most of the proteins identified in this analysis appeared to be related with protein repair or protection, cytoskeleton, signal transduction, immune system, metabolism, extracellular matrix and remodeling, transcription regulation, cell structure or differentiation and ion transport. One of up-regulated proteins in SCNT was TIMP-2 protein known to be related to extracellular matrix and remodeling during pregnancy. Western blot analysis showed an increased level of TIMP-2 in SCNT placenta compared to normal. Our results revealed composite profiles of key proteins involved in abnormal placenta derived from SCNT, and suggested expression abnormality of these genes in SCNT placenta, resulting in fetal losses following SCNT. PMID:16196098

  1. Effects of donor fibroblasts expressing OCT4 on bovine embryos generated by somatic cell nuclear transfer.

    PubMed

    Goissis, Marcelo D; Suhr, Steven T; Cibelli, Jose B

    2013-02-01

    The production of healthy, live, cloned animals by somatic cell nuclear transfer (SCNT) has been hampered by low efficiencies. Significant epigenetic changes must take place to ensure proper chromatin remodeling in SCNT. We hypothesized that exogenous expression of OCT4 in donor fibroblasts prior to its fusion with enucleated oocytes would facilitate SCNT reprogramming. We infected bovine adult fibroblasts with retroviral vectors containing yellow fluorescent protein (YFP) only, or the OCT4 gene fused to YFP (YO). We found that development to the blastocyst stage was not different between NT-YFP and NT-YO groups. NT-YFP embryos had the fewest trophoblast cells, measured by numbers of CDX2-positive cells. Fibroblasts expressing OCT4 had reduced levels of histone 3 lysine 9 or 27 trimethylation (H3K9me3 and H3K27me3, respectively). NT-YO blastocysts displayed higher H3K9me3 levels than IVF and NT-YFP embryos; however, they did not have different H3K27me3 levels. Levels of XIST mRNA expression in NT-YO and NT-YF were higher when compared to in vitro-fertilized blastocysts. We observed no differences in the expression of SOX2, NANOG, and CDX2. Although overexpression of OCT4 in donor cells increased H3K9me3 and did not reduce XIST gene expression, we show that a single transcription factor can affect the number of trophectoderm cells in bovine SCNT embryos. PMID:23276226

  2. Ovine induced pluripotent stem cells are resistant to reprogramming after nuclear transfer.

    PubMed

    German, Sergio D; Campbell, Keith H S; Thornton, Elisabeth; McLachlan, Gerry; Sweetman, Dylan; Alberio, Ramiro

    2015-02-01

    Induced pluripotent stem cells (iPSCs) share similar characteristics of indefinite in vitro growth with embryonic stem cells (ESCs) and may therefore serve as a useful tool for the targeted genetic modification of farm animals via nuclear transfer (NT). Derivation of stable ESC lines from farm animals has not been possible, therefore, it is important to determine whether iPSCs can be used as substitutes for ESCs in generating genetically modified cloned farm animals. We generated ovine iPSCs by conventional retroviral transduction using the four Yamanaka factors. These cells were basic fibroblast growth factor (bFGF)- and activin A-dependent, showed persistent expression of the transgenes, acquired chromosomal abnormalities, and failed to activate endogenous NANOG. Nonetheless, iPSCs could differentiate into the three somatic germ layers in vitro. Because cloning of farm animals is best achieved with diploid cells (G1/G0), we synchronized the iPSCs in G1 prior to NT. Despite the cell cycle synchronization, preimplantation development of iPSC-NT embryos was lower than with somatic cells (2% vs. 10% blastocysts, p<0.01). Furthermore, analysis of the blastocysts produced demonstrated persistent expression of the transgenes, aberrant expression of endogenous SOX2, and a failure to activate NANOG consistently. In contrast, gene expression in blastocysts produced with the parental fetal fibroblasts was similar to those generated by in vitro fertilization. Taken together, our data suggest that the persistent expression of the exogenous factors and the acquisition of chromosomal abnormalities are incompatible with normal development of NT embryos produced with iPSCs. PMID:25513856

  3. Vitamin C enhances in vitro and in vivo development of porcine somatic cell nuclear transfer embryos

    SciTech Connect

    Huang, Yongye; Tang, Xiaochun; Xie, Wanhua; Zhou, Yan; Li, Dong; Zhou, Yang; Zhu, Jianguo; Yuan, Ting; Lai, Liangxue; Pang, Daxin; Ouyang, Hongsheng

    2011-07-29

    Highlights: {yields} Report for the first time that vitamin C has a beneficial effect on the development of porcine SCNT embryos. {yields} The level of acH4K5 and Oct4 expression at blastocyst-stage was up-regulated after treatment. {yields} A higher rate of gestation and increased number of piglets born were harvested in the treated group. -- Abstract: The reprogramming of differentiated cells into a totipotent embryonic state through somatic cell nuclear transfer (SCNT) is still an inefficient process. Previous studies revealed that the generation of induced pluripotent stem (iPS) cells from mouse and human fibroblasts could be significantly enhanced with vitamin C treatment. Here, we investigated the effects of vitamin C, to our knowledge for the first time, on the in vitro and in vivo development of porcine SCNT embryos. The rate of blastocyst development in SCNT embryos treated with 50 {mu}g/mL vitamin C 15 h after activation (36.0%) was significantly higher than that of untreated SCNT embryos (11.5%). The enhanced in vitro development rate of vitamin C-treated embryos was associated with an increased acetylation level of histone H4 lysine 5 and higher Oct4, Sox2 and Klf4 expression levels in blastocysts, as determined by real-time PCR. In addition, treatment with vitamin C resulted in an increased pregnancy rate in pigs. These findings suggest that treatment with vitamin C is beneficial for enhancement of the in vitro and in vivo development of porcine SCNT embryos.

  4. [Dynamic changes of γ-tubulin in mouse somatic cell nuclear transferred embryos].

    PubMed

    Zhang, Qing-Hua; Lei, Lei

    2013-04-25

    The aim of the present study is to observe the dynamic changes of γ-tubulin in mouse somatic nuclear transferred (SCNT) embryos. The γ-tubulin was detected and analyzed in the enucleated oocyte and SCNT embryos by immunofluorescence and laser confocal microscopy. The results showed that γ-tubulin distributed in the cortex of the enucleated MII oocytes, and decreased in this area during the activation of oocytes. Meanwhile cytoplasmic asters appeared, but there was no spindle formed. Spindle formation could be observed in the enucleated oocytes which were injected with cumulus cells and activated by SrCl2. The spots-like γ-tubulin signals spread between chromosomes at the prophase, and the signals arrayed with spindle or aggregated at two poles of the spindle at the early metaphase. Furthermore, γ-tubulin signals were localized between the segregated sister chromatids at anaphase or telophase. Some reconstructed embryos exhibited advanced activation, showing abnormal spindles and aberrant distribution of γ-tubulin and chromosomes. Two spindles would be formed when the cumulus cell was injected into an intact oocyte, and the distribution of γ-tubulin was similar to that of the normal SCNT. Moreover, advanced activation also occurred in this case and formed either two small spindles or one big barrel-shaped spindle. These results suggest that γ-tubulin plays a pivotal role in spindle assembling in mouse SCNT embryos. The reconstructed oocytes were easily to be activated, and aberrant distribution of γ-tubulin is associated with formation of abnormal spindles and chromosome misalignment. PMID:23598871

  5. Best Practices for Finite Element Analysis of Spent Nuclear Fuel Transfer, Storage, and Transportation Systems

    SciTech Connect

    Bajwa, Christopher S.; Piotter, Jason; Cuta, Judith M.; Adkins, Harold E.; Klymyshyn, Nicholas A.; Fort, James A.; Suffield, Sarah R.

    2010-08-11

    Storage casks and transportation packages for spent nuclear fuel (SNF) are designed to confine SNF in sealed canisters or casks, provide structural integrity during accidents, and remove decay through a storage or transportation overpack. The transfer, storage, and transportation of SNF in dry storage casks and transport packages is regulated under 10 CFR Part 72 and 10 CFR Part 71, respectively. Finite Element Analysis (FEA) is used with increasing frequency in Safety Analysis Reports and other regulatory technical evaluations related to SNF casks and packages and their associated systems. Advances in computing power have made increasingly sophisticated FEA models more feasible, and as a result, the need for careful review of such models has also increased. This paper identifies best practice recommendations that stem from recent NRC review experience. The scope covers issues common to all commercially available FEA software, and the recommendations are applicable to any FEA software package. Three specific topics are addressed: general FEA practices, issues specific to thermal analyses, and issues specific to structural analyses. General FEA practices covers appropriate documentation of the model and results, which is important for an efficient review process. The thermal analysis best practices are related to cask analysis for steady state conditions and transient scenarios. The structural analysis best practices are related to the analysis of casks and associated payload during standard handling and drop scenarios. The best practices described in this paper are intended to identify FEA modeling issues and provide insights that can help minimize associated uncertainties and errors, in order to facilitate the NRC licensing review process.

  6. Improving the development of early bovine somatic-cell nuclear transfer embryos by treating adult donor cells with vitamin C.

    PubMed

    Chen, Huanhuan; Zhang, Lei; Guo, Zekun; Wang, Yongsheng; He, Rongjun; Qin, Yumin; Quan, Fusheng; Zhang, Yong

    2015-11-01

    Vitamin C (Vc) has been widely studied in cell and embryo culture, and has recently been demonstrated to promote cellular reprogramming. The objective of this study was to identify a suitable Vc concentration that, when used to treat adult bovine fibroblasts serving as donor cells for nuclear transfer, improved donor-cell physiology and the developmental potential of the cloned embryos that the donor nuclei were used to create. A Vc concentration of 0.15 mM promoted cell proliferation and increased donor-cell 5-hydroxy methyl cytosine levels 2.73-fold (P < 0.05). The blastocyst rate was also significantly improved after nuclear transfer (39.6% treated vs. 26.0% control, P < 0.05); the average number of apoptotic cells in cloned blastocysts was significantly reduced (2.2 vs. 4.4, P < 0.05); and the inner cell mass-to-trophectoderm ratio (38.25% vs. 30.75%, P < 0.05) and expression of SOX2 (3.71-fold, P < 0.05) and POU5F1 (3.15-fold, P < 0.05) were significantly increased. These results suggested that Vc promotes cell proliferation, decreases DNA methylation levels in donor cells, and improves the developmental competence of bovine somatic-cell nuclear transfer embryos. PMID:26212732

  7. Frequent somatic transfer of mitochondrial DNA into the nuclear genome of human cancer cells

    PubMed Central

    Ju, Young Seok; Tubio, Jose M.C.; Mifsud, William; Fu, Beiyuan; Davies, Helen R.; Ramakrishna, Manasa; Li, Yilong; Yates, Lucy; Gundem, Gunes; Tarpey, Patrick S.; Behjati, Sam; Papaemmanuil, Elli; Martin, Sancha; Fullam, Anthony; Gerstung, Moritz; Nangalia, Jyoti; Green, Anthony R.; Caldas, Carlos; Borg, Åke; Tutt, Andrew; Lee, Ming Ta Michael; van't Veer, Laura J.; Tan, Benita K.T.; Aparicio, Samuel; Span, Paul N.; Martens, John W.M.; Knappskog, Stian; Vincent-Salomon, Anne; Børresen-Dale, Anne-Lise; Eyfjörd, Jórunn Erla; Flanagan, Adrienne M.; Foster, Christopher; Neal, David E.; Cooper, Colin; Eeles, Rosalind; Lakhani, Sunil R.; Desmedt, Christine; Thomas, Gilles; Richardson, Andrea L.; Purdie, Colin A.; Thompson, Alastair M.; McDermott, Ultan; Yang, Fengtang; Nik-Zainal, Serena; Campbell, Peter J.; Stratton, Michael R.

    2015-01-01

    Mitochondrial genomes are separated from the nuclear genome for most of the cell cycle by the nuclear double membrane, intervening cytoplasm, and the mitochondrial double membrane. Despite these physical barriers, we show that somatically acquired mitochondrial-nuclear genome fusion sequences are present in cancer cells. Most occur in conjunction with intranuclear genomic rearrangements, and the features of the fusion fragments indicate that nonhomologous end joining and/or replication-dependent DNA double-strand break repair are the dominant mechanisms involved. Remarkably, mitochondrial-nuclear genome fusions occur at a similar rate per base pair of DNA as interchromosomal nuclear rearrangements, indicating the presence of a high frequency of contact between mitochondrial and nuclear DNA in some somatic cells. Transmission of mitochondrial DNA to the nuclear genome occurs in neoplastically transformed cells, but we do not exclude the possibility that some mitochondrial-nuclear DNA fusions observed in cancer occurred years earlier in normal somatic cells. PMID:25963125

  8. Frequent somatic transfer of mitochondrial DNA into the nuclear genome of human cancer cells.

    PubMed

    Ju, Young Seok; Tubio, Jose M C; Mifsud, William; Fu, Beiyuan; Davies, Helen R; Ramakrishna, Manasa; Li, Yilong; Yates, Lucy; Gundem, Gunes; Tarpey, Patrick S; Behjati, Sam; Papaemmanuil, Elli; Martin, Sancha; Fullam, Anthony; Gerstung, Moritz; Nangalia, Jyoti; Green, Anthony R; Caldas, Carlos; Borg, Åke; Tutt, Andrew; Lee, Ming Ta Michael; van't Veer, Laura J; Tan, Benita K T; Aparicio, Samuel; Span, Paul N; Martens, John W M; Knappskog, Stian; Vincent-Salomon, Anne; Børresen-Dale, Anne-Lise; Eyfjörd, Jórunn Erla; Flanagan, Adrienne M; Foster, Christopher; Neal, David E; Cooper, Colin; Eeles, Rosalind; Lakhani, Sunil R; Desmedt, Christine; Thomas, Gilles; Richardson, Andrea L; Purdie, Colin A; Thompson, Alastair M; McDermott, Ultan; Yang, Fengtang; Nik-Zainal, Serena; Campbell, Peter J; Stratton, Michael R

    2015-06-01

    Mitochondrial genomes are separated from the nuclear genome for most of the cell cycle by the nuclear double membrane, intervening cytoplasm, and the mitochondrial double membrane. Despite these physical barriers, we show that somatically acquired mitochondrial-nuclear genome fusion sequences are present in cancer cells. Most occur in conjunction with intranuclear genomic rearrangements, and the features of the fusion fragments indicate that nonhomologous end joining and/or replication-dependent DNA double-strand break repair are the dominant mechanisms involved. Remarkably, mitochondrial-nuclear genome fusions occur at a similar rate per base pair of DNA as interchromosomal nuclear rearrangements, indicating the presence of a high frequency of contact between mitochondrial and nuclear DNA in some somatic cells. Transmission of mitochondrial DNA to the nuclear genome occurs in neoplastically transformed cells, but we do not exclude the possibility that some mitochondrial-nuclear DNA fusions observed in cancer occurred years earlier in normal somatic cells. PMID:25963125

  9. Comparison of microinjection (piezo-electric) and cell fusion for nuclear transfer success with different cell types in cattle.

    PubMed

    Galli, Cesare; Lagutina, Irina; Vassiliev, Ivan; Duchi, Roberto; Lazzari, Giovanna

    2002-01-01

    Amongst the many variables that can determine success of cloning, the source of nuclei, the procedure used for nuclear transfer, and the activation of the reconstructed embryo are very important aspects. In this study, we have compared the two most common procedures for transferring nuclei to enucleated oocytes--cell fusion (CF) and piezoelectric microinjection (PEM) using different somatic cells--and we have investigated the effect of different activation procedures. Granulosa cells and fibroblasts were grown to confluency or in low serum to induce a quiescent state, while lymphocytes were thawed immediately prior to use. Enucleated oocytes were reconstructed either with CF or PME by 21-23 h postmaturation. For cell fusion, one pulse of 1 kVolt/cm for 30 microsec was used; for PEM, the cell membrane was broken by repeated pipetting and transferred in a 12% PVP solution to facilitate injection. Manipulated oocytes were activated with ionomycin and cycloheximide (CHX) or 6-DMAP (DMAP) and cultured in microdrops of SOF-BSA-AA. On day 7 (day 0: nuclear transfer), embryo development was evaluated and embryos were either transferred fresh or were frozen. More embryos were successfully reconstructed with PEM than CF, but a higher number of reconstructed embryos by CF developed to blastocyst at D + 7. In addition, in both systems more embryos were obtained after activation with DMAP than with CHX. The transfer of 141 embryos to recipients resulted in a pregnancy rate of 50%, and no differences were observed between the source of donor cell, the reconstruction methods, or the activation protocol. Six calves were delivered at term, and four survived. High pregnancy losses were observed throughout the gestation period. PMID:12398800

  10. The Arabidopsis repressor of light signaling, COP1, is regulated by nuclear exclusion: Mutational analysis by bioluminescence resonance energy transfer

    PubMed Central

    Subramanian, Chitra; Kim, Byung-Hoon; Lyssenko, Nicholas N.; Xu, Xiaodong; Johnson, Carl Hirschie; von Arnim, Albrecht G.

    2004-01-01

    Bioluminescence resonance energy transfer (BRET) between Renilla luciferase and yellow fluorescent protein has been adapted to serve as a real-time reporter on protein-protein interactions in live plant cells by using the Arabidopsis Constitutive photomorphogenesis 1 (COP1) protein as a model system. COP1 is a repressor of light signal transduction that functions as part of a nuclear E3 ubiquitin ligase. COP1 possesses a leucine-rich nuclear-exclusion signal that resides in a domain implicated in COP1 dimerization. BRET was applied in conjunction with site-directed mutagenesis to explore the respective contributions of the nuclear-exclusion and dimerization motifs to the regulation of COP1 activity in vivo. One specific mutant protein, COP1L105A, showed increased nuclear accumulation but retained the ability to dimerize, as monitored by BRET, whereas other mutations inhibited both nuclear exclusion and COP1 dimerization. Mutant rescue and overexpression experiments indicated that nuclear exclusion of COP1 protein is a rate-limiting step in light signal transduction. PMID:15084749