Bibliografías temáticas / BAC-A

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Literatura académica sobre el tema "BAC-A"

Autor: Grafiati
Publicado: 11 de marzo de 2023

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Artículos de revistas sobre el tema "BAC-A"

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Inoue, Takako, Haruyoshi Tomita y Yasuyoshi Ike. "Bac 32, a Novel Bacteriocin Widely Disseminated among Clinical Isolates of Enterococcus faecium". Antimicrobial Agents and Chemotherapy 50, n.º 4 (abril de 2006): 1202–12. http://dx.doi.org/10.1128/aac.50.4.1202-1212.2006.

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ABSTRACT A total of 636 vancomycin-resistant Enterococcus faecium (VRE) isolates that had been obtained between 1994 and 1999 from the Medical School Hospital of the University of Michigan, Ann Arbor, were tested for bacteriocin production. Two hundred seventy-seven (44%) of the strains were bacteriocinogenic; and 193 of these exhibited activity against Enterococcus faecium, Enterococcus hirae, and Enterococcus durans. Strain VRE200 harbors the highly efficient conjugative gentamicin resistance plasmid pG200 (70 kb) and bacteriocin plasmid pTI1 (12.5 kb). The bacteriocin encoded on pTI1 was designated bacteriocin 32 (Bac 32). Bacteriocin 32 was active against E. faecium, E. hirae, and E. durans but showed no activity against Listeria monocytogenes. The Bac 32 genetic locus consists of a bacteriocin gene (bacA) and an immunity gene (bacB). Neither of these genes showed significant homology to any known bacteriocin determinants. The deduced bacA product is 89 amino acids in length, with a putative signal peptide of 19 amino acids at the N terminus. The bacB gene encodes a deduced 55-amino-acid protein without a signal sequence. One hundred eighty-nine strains (97.9%) of the 193 strains with activity against the 3 test enterococcal strains gave rise to the expected specific PCR product with a primer specific for bacA, indicating that there is a high incidence of Bac 32 production among VRE clinical isolates. Data from Southern analyses of plasmid DNA from 189 of the Bac 32-producing strains with a plasmid pTI1-specific probe suggested that 137 (72.5%) of the strains harbored a pTI1-type plasmid. Bac 32 or Bac 32-type bacteriocin activity and the determinant genes were also identified in 22 (39.3%) of a total of 56 vancomycin-sensitive E. faecium clinical isolates, which suggests that this bacteriocin is widely disseminated among E. faecium strains.
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Malik, Amarila, Elita Yuliantie, Nisa Yulianti Suprahman, Theresa Linardi, Angelina Wening Widiyanti, Jeanita Haldy, Catherine Tjia y Hiroshi Takagi. "Construction and Functional Analysis of the Recombinant Bacteriocins Weissellicin-MBF from Weissella confusa MBF8-1". Current Pharmaceutical Biotechnology 22, n.º 1 (31 de diciembre de 2020): 115–22. http://dx.doi.org/10.2174/1389201021666200611111040.

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Background: Bacteriocins (Bac1, Bac2, and Bac3) from Weissella confusa MBF8-1, weissellicin- MBF, have been reported as potential alternative substances as well as complements to the existing antibiotics against many antimicrobial-resistant pathogens. Previously, the genes encoded in the large plasmid, pWcMBF8-1, and the spermicidal activity of their synthetic peptides, originally discovered Indonesia, have been studied. Three synthetic bacteriocins peptides of this weissellicin-MBF have been reported for their potential activities, i.e. antibacterial and spermicidal. Objective: The aim of this study was to construct the recombinant Bacteriocin (r-Bac) genes, as well as to investigate the gene expressions and their functional analysis. Method: Here, the recombinant Bacteriocin (r-Bac) genes were constructed and the recombinant peptides (r-Bac1, r-Bac2, and r-Bac3) in B. subtilis DB403 cells were produced on a large scale. After purification, using the His-tag affinity column, their potential bioactivities were measured as well as their antibacterial minimum inhibitory concentrations against Leuconostoc mesenteroides and Micrococcus luteus, were determined. Results: Pure His-tag-recombinant Bac1, Bac2, and Bac3 were obtained and they could inhibit the growth of L. mesenteroides and M. luteus. Conclusion: The recombinant bacteriocin could be obtained although with weak activity in inhibiting gram-positive bacterial growth.
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Murrell, Isa, Gavin S. Wilkie, Andrew J. Davison, Evelina Statkute, Ceri A. Fielding, Peter Tomasec, Gavin W. G. Wilkinson y Richard J. Stanton. "Genetic Stability of Bacterial Artificial Chromosome-Derived Human Cytomegalovirus during CultureIn Vitro". Journal of Virology 90, n.º 8 (3 de febrero de 2016): 3929–43. http://dx.doi.org/10.1128/jvi.02858-15.

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ABSTRACTClinical human cytomegalovirus (HCMV) strains invariably mutate when propagatedin vitro. Mutations in gene RL13 are selected in all cell types, whereas in fibroblasts mutants in the UL128 locus (UL128L; genes UL128, UL130, and UL131A) are also selected. In addition, sporadic mutations are selected elsewhere in the genome in all cell types. We sought to investigate conditions under which HCMV can be propagated without incurring genetic defects. Bacterial artificial chromosomes (BACs) provide a stable, genetically defined source of viral genome. Viruses were generated from BACs containing the genomes of strains TR, TB40, FIX, and Merlin, as well as from Merlin-BAC recombinants containing variant nucleotides in UL128L from TB40-BAC4 or FIX-BAC. Propagation of viruses derived from TR-BAC, TB40-BAC4, and FIX-BAC in either fibroblast or epithelial cells was associated with the generation of defects around the prokaryotic vector, which is retained in the unique short (US) region of viruses. This was not observed for Merlin-BAC, from which the vector is excised in derived viruses; however, propagation in epithelial cells was consistently associated with mutations in the unique longb′ (UL/b′) region, all impacting on gene UL141. Viruses derived from Merlin-BAC in fibroblasts had mutations in UL128L, but mutations occurred less frequently with recombinants containing UL128L nucleotides from TB40-BAC4 or FIX-BAC. Viruses derived from a Merlin-BAC derivative in which RL13 and UL128L were either mutated or repressed were remarkably stable in fibroblasts. Thus, HCMV containing a wild-type gene complement can be generatedin vitroby deriving virus from a self-excising BAC in fibroblasts and repressing RL13 and UL128L.IMPORTANCEResearchers should aim to study viruses that accurately represent the causative agents of disease. This is problematic for HCMV because clinical strains mutate rapidly when propagatedin vitro, becoming less cell associated, altered in tropism, more susceptible to natural killer cells, and less pathogenic. Following isolation from clinical material, HCMV genomes can be stabilized by cloning into bacterial artificial chromosomes (BACs), and then virus is regenerated by DNA transfection. However, mutations can occur not only during isolation prior to BAC cloning but also when virus is regenerated. We have identified conditions under which BAC-derived viruses containing an intact, wild-type genome can be propagatedin vitrowith minimal risk of mutants being selected, enabling studies of viruses expressing the gene complement of a clinical strain. However, even under these optimized conditions, sporadic mutations can occur, highlighting the advisability of sequencing the HCMV stocks used in experiments.
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Yamashita, Hitoshi, Haruyoshi Tomita, Takako Inoue y Yasuyoshi Ike. "Genetic Organization and Mode of Action of a Novel Bacteriocin, Bacteriocin 51: Determinant of VanA-Type Vancomycin-Resistant Enterococcus faecium". Antimicrobial Agents and Chemotherapy 55, n.º 9 (27 de junio de 2011): 4352–60. http://dx.doi.org/10.1128/aac.01274-10.

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ABSTRACTBacteriocin 51 (Bac 51) is encoded on the mobile plasmid pHY (6,037 bp), which was isolated from vancomycin-resistantEnterococcus faeciumVRE38. Bacteriocin 51 is active againstE. faecium,E. hirae, andE. durans. Sequence analysis of pHY showed that it encodes nine open reading frames (ORFs) from ORF1 to ORF9 (in that order). Genetic analysis suggested that ORF1 and ORF2, which were designatedbacAandbacB, respectively, are the bacteriocin and immunity genes.bacAencodes a 144-amino-acid protein. The deduced BacA protein has a typical signal sequence at its amino terminus, and a potential signal peptidase-processing site corresponding to the V-E-A sequence is located between the 37th and 39th amino acids. The predicted mature BacA protein consists of 105 amino acids. A potential promoter sequence was identified upstream of the start codon.bacBencodes a 55-amino-acid protein. No obvious promoter or terminator sequence was identified betweenbacAandbacB. Northern blot analysis ofbacAandbacBwith abacARNA probe produced a transcript of approximately 700 nucleotides, which corresponded to the combined nucleotide sizes ofbacAandbacB, indicating that transcription was initiated from the promoter upstream ofbacA, continued throughbacB, and was terminated at the terminator downstream ofbacB. The transcription start site was determined to be the T nucleotide located 6 nucleotides downstream from the −10 promoter sequence. These results indicate thatbacAandbacBconstitute an operon and thatbacAis the bacteriocin structural gene whilebacBis the immunity gene. The purified C-terminally His tagged BacA protein of Bac 51 showed bacteriostatic activity against the indicator strain. The purified C-terminally His tagged BacA protein of Bac 32 (whose mature BacA protein has 54 amino acids) and the culture filtrates of the Bac 31- and Bac 43-producingE. faecalisstrain FA2-2 showed bactericidal activity. Bac 31 and Bac 43 are pore-forming bacteriocins, unlike the newly characterized bacteriocin Bac 51.
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Oh, Seungdae, Zohre Kurt, Despina Tsementzi, Michael R. Weigand, Minjae Kim, Janet K. Hatt, Madan Tandukar, Spyros G. Pavlostathis, Jim C. Spain y Konstantinos T. Konstantinidis. "Microbial Community Degradation of Widely Used Quaternary Ammonium Disinfectants". Applied and Environmental Microbiology 80, n.º 19 (20 de junio de 2014): 5892–900. http://dx.doi.org/10.1128/aem.01255-14.

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ABSTRACTBenzalkonium chlorides (BACs) are disinfectants widely used in a variety of clinical and environmental settings to prevent microbial infections, and they are frequently detected in nontarget environments, such as aquatic and engineered biological systems, even at toxic levels. Therefore, microbial degradation of BACs has important ramifications for alleviating disinfectant toxicity in nontarget environments as well as compromising disinfectant efficacy in target environments. However, how natural microbial communities respond to BAC exposure and what genes underlie BAC biodegradation remain elusive. Our previous metagenomic analysis of a river sediment microbial community revealed that BAC exposure selected for a low-diversity community, dominated by several members of thePseudomonasgenus that quickly degraded BACs. To elucidate the genetic determinants of BAC degradation, we conducted time-series metatranscriptomic analysis of this microbial community during a complete feeding cycle with BACs as the sole carbon and energy source under aerobic conditions. Metatranscriptomic profiles revealed a candidate gene for BAC dealkylation, the first step in BAC biodegradation that results in a product 500 times less toxic. Subsequent biochemical assays and isolate characterization verified that the putative amine oxidase gene product was functionally capable of initiating BAC degradation. Our analysis also revealed cooperative interactions among community members to alleviate BAC toxicity, such as the further degradation of BAC dealkylation by-products by organisms not encoding amine oxidase. Collectively, our results advance the understanding of BAC aerobic biodegradation and provide genetic biomarkers to assess the critical first step of this process in nontarget environments.
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Shah, Raina J., Charles G. Burhans, Michael J. Wise, J. Paul Frantz y Timothy P. Rhoades. "Exploring the relationship between risk perception and U.S. driver acceptance of a 0.05% BAC limit". Proceedings of the Human Factors and Ergonomics Society Annual Meeting 60, n.º 1 (septiembre de 2016): 1661–65. http://dx.doi.org/10.1177/1541931213601382.

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The National Transportation Safety Board (NTSB) has recently recommended that states reduce the legal blood alcohol concentration (BAC) limit for driving from 0.08% to 0.05%. This study assessed attitudes of drivers toward this recommendation. It also assessed the extent to which attitudes toward lowering the legal BAC limit were related to the perceived risk of driving at different BAC levels as compared to other factors. A majority of drivers surveyed (54%) were in favor of the 0.05% BAC limit proposal, with 26% against it and 20% neutral toward it. Those who believed that driving at 0.05% BAC posed an increased risk for a crash were more likely to support the proposal than those who did not think that driving at 0.05% BAC posed an increased crash risk. However, perceptions about the risk posed by driving at various BACs did not completely determine policy preferences. Some participants supported the 0.05% BAC limit even though they did not perceive a risk reduction benefit, while others perceived a risk reduction benefit of a 0.05% BAC limit but still did not support the policy. Implications for the role of risk perceptions in policy preferences are discussed.
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Sinzger, Christian, Gabriele Hahn, Margarete Digel, Ruth Katona, Kerstin Laib Sampaio, Martin Messerle, Hartmut Hengel, Ulrich Koszinowski, Wolfram Brune y Barbara Adler. "Cloning and sequencing of a highly productive, endotheliotropic virus strain derived from human cytomegalovirus TB40/E". Journal of General Virology 89, n.º 2 (1 de febrero de 2008): 359–68. http://dx.doi.org/10.1099/vir.0.83286-0.

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Human cytomegalovirus (HCMV) strain TB40/E, replicates efficiently, exhibits a broad cell tropism and is widely used for infection of endothelial cells and monocyte-derived cells yet has not been available in a phenotypically homogeneous form compatible with genetic analysis. To overcome this problem, we cloned the TB40/E strain into a bacterial artificial chromosome (BAC) vector. Both highly endotheliotropic and poorly endotheliotropic virus clones, representing three distinct restriction fragment patterns, were reconstituted after transfection of BAC clones derived from previously plaque-purified strain TB40/E. For one of the highly endotheliotropic clones, TB40-BAC4, we provide the genome sequence. Two BACs with identical restriction fragment patterns but different cell tropism were further analysed in the UL128-UL131A gene region. Sequence analysis revealed one coding-relevant adenine insertion at position 332 of UL128 in the BAC of the poorly endotheliotropic virus, which caused a frameshift in the C-terminal part of the coding sequence. Removal of this insertion by markerless mutagenesis restored the highly endotheliotropic phenotype, indicating that the loss of endothelial cell tropism was caused by this insertion. In conclusion, HCMV strain TB40/E, which combines the high endothelial cell tropism of a clinical isolate with the high titre growth of a cell culture adapted strain, is now available as a BAC clone suitable for genetic engineering. The results also suggest BAC cloning as a suitable method for selection of genetically defined virus clones.
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Schumacher, Daniel, B. Karsten Tischer, Walter Fuchs y Nikolaus Osterrieder. "Reconstitution of Marek's Disease Virus Serotype 1 (MDV-1) from DNA Cloned as a Bacterial Artificial Chromosome and Characterization of a Glycoprotein B-Negative MDV-1 Mutant". Journal of Virology 74, n.º 23 (1 de diciembre de 2000): 11088–98. http://dx.doi.org/10.1128/jvi.74.23.11088-11098.2000.

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ABSTRACT The complete genome of Marek's disease virus serotype 1 (MDV-1) strain 584Ap80C was cloned in Escherichia coli as a bacterial artificial chromosome (BAC). BAC vector sequences were introduced into the US2 locus of the MDV-1 genome by homologous recombination. Viral DNA containing the BAC vector was used to transform Escherichia coli strain DH10B, and several colonies harboring the complete MDV-1 genome as an F plasmid (MDV-1 BACs) were identified. DNA from various MDV-1 BACs was transfected into chicken embryo fibroblasts, and from 3 days after transfection, infectious MDV-1 was obtained. Growth of MDV-1 recovered from BACs was indistinguishable from that of the parental virus, as assessed by plaque formation and determination of growth curves. In one of the MDV-1 BAC clones, sequences encoding glycoprotein B (gB) were deleted by one-step mutagenesis using a linear DNA fragment amplified by PCR. Mutant MDV-1 recovered after transfection of BAC DNA that harbored a 2.0-kbp deletion of the 2.6-kbp gB gene were able to grow and induce MDV-1-specific plaques only on cells providing MDV-1 gB in trans. The gB-negative virus reported here represents the first MDV-1 mutant with a deletion of an essential gene and demonstrates the power and usefulness of BACs to analyze genes and gene products in slowly growing and strictly cell-associated herpesviruses.
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Zhao, S. "A comprehensive BAC resource". Nucleic Acids Research 29, n.º 1 (1 de enero de 2001): 141–43. http://dx.doi.org/10.1093/nar/29.1.141.

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Wang, Min Qi, Mary E. Nicholson, Beverly S. Mahoney, Yuhua Li y Mike A. Perko. "Proprioceptive Responses under Rising and Falling BACs: A Test of the Mellanby Effect". Perceptual and Motor Skills 77, n.º 1 (agosto de 1993): 83–88. http://dx.doi.org/10.2466/pms.1993.77.1.83.

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This study examined proprioceptive responses under equivalent rising and falling blood alcohol concentrations (BAC), using a repeated-measures design. Seven volunteer subjects, 21 to 35 years of age, participated in the study. After alcohol consumption, BAC readings were obtained every 5 minutes, and the proprioceptive responses were measured at the following BAC levels (in %): 0 (baseline), rising 0.05, 0.075, 0.1, falling 0.075, and 0.05. The analysis focused on the comparisons of these measures at the equivalent rising and falling 0.05% and at the 0.075% BACs. Results showed that the proprioceptive response was less accurate during the rising than the falling BACs.
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Tesis sobre el tema "BAC-A"

1

Özdemir, Nehir. "Construction of a BAC library for sunflower". [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=960903658.

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Kim, Kenneth Lee. "Sequence Analysis of a Human Bac Construct for Mouse Transgenesis". Thesis, The University of Arizona, 2011. http://hdl.handle.net/10150/144540.

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Hess, Gregory. "Toward positional cloning of everblooming gene (evb) in plants: a BAC library of Rosa chinensis cv. old blush". Texas A&M University, 2005. http://hdl.handle.net/1969.1/4318.

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A majority of commercial rose varieties bloom repeatedly throughout the year, as compared to most rose species, other woody ornamentals, and fruit crops that bloom once a year. This recurrent flowering feature of the commercial roses resulted from a flowering mutation named everblooming (evb). The mutation is recessive to once blooming and is found in the rose species Rosa chinensis. Although several molecular maps have been developed for rose, little is known about the evb gene, except for its classic genetics. The purpose of this study was to develop a large-insert bacterial artificial chromosome (BAC) library as a starting tool for molecular cloning and analysis of the evb gene by map-based cloning. To construct the large-insert BAC library, nuclear megabase-size DNA was isolated from the recurrent blooming diploid species, Rosa chinensis cv. Old Blush. The DNA was then partially digested with BamHI and separated on agarose gels by multi-phase pulsed-field gel electrophoresis. Size selected fragments estimated between 100 kb and 150 kb in size were cloned into the pECBAC1 BAC vector and the clones having rose DNA inserts were arrayed in 80 384-well microplates individually, with each clone being barcoded. The library contains 30,720 clones, has an average insert size of 108 kb and covers roughly 5.9x genome equivalents, with a >99% probability of isolating a single-copy clone from the library. The library is now available to be screened with the genes cloned from other species that control vernalization and floral development and will be used in mapbased cloning of the evb gene using a Rosa wichuraiana (‘Basye’s Thornless’) x ‘Old Blush’ backcross population.
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Molas, Casacuberta Susanna 1985. "Nicotine addiction phenotypes in a BAC transgenic mouse model overexpressing the CHRNA5/A3/B4 genomic cluster". Doctoral thesis, Universitat Pompeu Fabra, 2012. http://hdl.handle.net/10803/104155.

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The CHRNA5/A3/B4 genomic cluster encodes for the alpha5, alpha3 and beta4 subunits of the nicotinic acetylcholine receptors (nAChRs). Human genetic studies have revealed a significant association of variants in this genomic region with nicotine dependence. However, the mechanisms through which overexpression of these three subunits may influence smoking-related behaviours is not understood. To gain insight in the possible mechanisms, we used a BAC transgenic mouse model overexpressing this cluster containing the three genes together with their transcriptional regulatory elements. We found that overexpression of the cluster: i) increases sensitivity to the pharmacological effects of nicotine; ii) modifies particular cognitive domains associated to drug addiction and hippocampal neuronal complexity and synaptic plasticity; and iii) shifts the rewarding and aversive properties of nicotine and the manifestation of nicotine-withdrawal syndrome. Our study suggests that the genomic cluster CHRNA5/A3/B4 contributes to genetic vulnerability to nicotine addiction and promotes smoking-related behaviours possibly through hippocampal plasticity changes.
El cluster genòmic CHRNA5/A3/B4 codifica per les subunitats alfa5, alfa3 i beta4 dels receptors d’acetilcolina (nAChRs). Estudis de genètica humana han revelat que variants en aquesta regió genòmica estan significativament associats a la dependencia a nicotina. Malauradament, els mecanismes pels quals la sobreexpressió d’aquestes tres subunitats influencia comportaments relacionats amb el consum de tabac no són del tot coneguts. Per tal d’entendre els possibles mecanismes, hem utilitzat un model de ratolí transgènic que sobreexpressa aquest cluster amb els tres gens i les seus elements de regulació transcripcional. Hem trobat que la sobreexpressió del cluster: i) incrementa la sensibilitat als efectes farmacològics de la nicotina; ii) modifica determinats dominis cognitius associats a l’addicció a droges i la complexitat neuronal i plasticitat sinàpica de l’hipocamp; a més a més iii) canvia les propietats de recompensa i aversió de la nicotina i la manifestació del síndrome d’abstinència. El nostre estudi suggereix que el cluster genòmic CHRNA5/A3/B4 contribueix a la vulnerabilitat genètica a l’adicció a la nicotina i promou comportaments relacionats amb el consum de tabac possiblement a través de canvis de plasticitiat a l’hipocamp.
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Martins-Wess, Flávia. "Construction of a BAC-PAC contig of SSC 6q1.2 and comparative analysis of this genome region". [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970644604.

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Sloan, Maximilian. "The behavioural and molecular characterisation of a novel LRRK2 BAC transgenic rat model of Parkinson's disease". Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:c2058b71-df43-47cd-a794-13184bacf313.

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Gu, Yong, Yaqin Ma, Naxin Huo, John Vogel, Frank You, Gerard Lazo, William Nelson et al. "A BAC-based physical map of Brachypodium distachyon and its comparative analysis with rice and wheat". BioMed Central, 2009. http://hdl.handle.net/10150/610004.

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BACKGROUND:Brachypodium distachyon (Brachypodium) has been recognized as a new model species for comparative and functional genomics of cereal and bioenergy crops because it possesses many biological attributes desirable in a model, such as a small genome size, short stature, self-pollinating habit, and short generation cycle. To maximize the utility of Brachypodium as a model for basic and applied research it is necessary to develop genomic resources for it. A BAC-based physical map is one of them. A physical map will facilitate analysis of genome structure, comparative genomics, and assembly of the entire genome sequence.RESULTS:A total of 67,151 Brachypodium BAC clones were fingerprinted with the SNaPshot HICF fingerprinting method and a genome-wide physical map of the Brachypodium genome was constructed. The map consisted of 671 contigs and 2,161 clones remained as singletons. The contigs and singletons spanned 414 Mb. A total of 13,970 gene-related sequences were detected in the BAC end sequences (BES). These gene tags aligned 345 contigs with 336 Mb of rice genome sequence, showing that Brachypodium and rice genomes are generally highly colinear. Divergent regions were mainly in the rice centromeric regions. A dot-plot of Brachypodium contigs against the rice genome sequences revealed remnants of the whole-genome duplication caused by paleotetraploidy, which were previously found in rice and sorghum. Brachypodium contigs were anchored to the wheat deletion bin maps with the BES gene-tags, opening the door to Brachypodium-Triticeae comparative genomics.CONCLUSION:The construction of the Brachypodium physical map, and its comparison with the rice genome sequence demonstrated the utility of the SNaPshot-HICF method in the construction of BAC-based physical maps. The map represents an important genomic resource for the completion of Brachypodium genome sequence and grass comparative genomics. A draft of the physical map and its comparisons with rice and wheat are available at http://phymap.ucdavis.edu/brachypodium/ webcite.
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Taguchi, Tomoyuki. "α-Synuclein BAC transgenic mice exhibit RBD-like behaviour and hyposmia: a prodromal Parkinson’s disease model". Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263550.

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Shirasaki, Dyna Irony. "A proteomic probing of the full-length Huntingtin interactome based on a novel BAC transgenic mouse model of Huntington's disease". Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1707554011&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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Figueira, Thais Rezende, Vagner Okura, da Silva Rodrigues, da Silva Jose, Dave Kudrna, Jetty Ammiraju, Jayson Talag, Rod Wing y Paulo Arruda. "A BAC library of the SP80-3280 sugarcane variety (saccharum sp.) and its inferred microsynteny with the sorghum genome". BioMed Central, 2012. http://hdl.handle.net/10150/610097.

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BACKGROUND:Sugarcane breeding has significantly progressed in the last 30 years, but achieving additional yield gains has been difficult because of the constraints imposed by the complex ploidy of this crop. Sugarcane cultivars are interspecific hybrids between Saccharum officinarum and Saccharum spontaneum. S. officinarum is an octoploid with 2n=80 chromosomes while S. spontaneum has 2n=40 to 128 chromosomes and ploidy varying from 5 to 16. The hybrid genome is composed of 70-80%S. officinaram and 5-20%S. spontaneum chromosomes and a small proportion of recombinants. Sequencing the genome of this complex crop may help identify useful genes, either per se or through comparative genomics using closely related grasses. The construction and sequencing of a bacterial artificial chromosome (BAC) library of an elite commercial variety of sugarcane could help assembly the sugarcane genome.RESULTS:A BAC library designated SS_SBa was constructed with DNA isolated from the commercial sugarcane variety SP80-3280. The library contains 36,864 clones with an average insert size of 125 Kb, 88% of which has inserts larger than 90 Kb. Based on the estimated genome size of 760-930 Mb, the library exhibits 5-6 times coverage the monoploid sugarcane genome. Bidirectional BAC end sequencing (BESs) from a random sample of 192 BAC clones sampled genes and repetitive elements of the sugarcane genome. Forty-five per cent of the total BES nucleotides represents repetitive elements, 83% of which belonging to LTR retrotransposons. Alignment of BESs corresponding to 42 BACs to the genome sequence of the 10 sorghum chromosomes revealed regions of microsynteny, with expansions and contractions of sorghum genome regions relative to the sugarcane BAC clones. In general, the sampled sorghum genome regions presented an average 29% expansion in relation to the sugarcane syntenic BACs.CONCLUSION:The SS_SBa BAC library represents a new resource for sugarcane genome sequencing. An analysis of insert size, genome coverage and orthologous alignment with the sorghum genome revealed that the library presents whole genome coverage. The comparison of syntenic regions of the sorghum genome to 42 SS_SBa BES pairs revealed that the sorghum genome is expanded in relation to the sugarcane genome.
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Libros sobre el tema "BAC-A"

1

Bac si: A novel. Denver: Outskirts Press, 2015.

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2

Bac-si: A doctor remembers Vietnam. Honolulu, Hawaii: Taote Pub., 1991.

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3

United States. National Highway Traffic Safety Administration, ed. .08 BAC limit saves lives: Why every state needs a .08 BAC law. [Washington, D.C.?: U.S. Dept. of Transportation, National Highway Traffic Safety Administration, 1995.

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1949-, Bellet Alain, ed. Les années lycée: Le bac a 200 ans. Paris: Solar éditions, 2008.

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Harrison, Judy A. He's bac!: A children's guide to keeping food safe. Washington, D.C.?]: Distributed by the Food Safety and Inspection Service, U.S. Dept. of Agriculture, 2000.

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Maths: Bac 93 : A-B-D-D' : [sujets] non corrigés. Paris: Nathan, 1992.

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Ohio. Dept. of Public Safety, ed. Blood Alcohol Content (BAC)--what is it?: A dangerous mix. [Columbus]: Ohio Dept. of Public Safety, 1998.

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Kermarec, Christine. Franc ʹais: Bac pro : la pre paration a l'e preuve. Paris: Nathan technique, 2009.

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Oxenham, Marc F. Man Bac: The Excavation of a Neolithic Site in Northern Vietnam. Canberra: ANU Press, 2011.

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1957-, McCain Edward, ed. A gift of angels: The art of Mission San Xavier del Bac. Tucson: University of Arizona Press, 2010.

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Capítulos de libros sobre el tema "BAC-A"

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Venturini, Luca, Paolo Garza y Daniele Apiletti. "BAC: A Bagged Associative Classifier for Big Data Frameworks". En Communications in Computer and Information Science, 137–46. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-44066-8_15.

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Agca, Cavit y Christian Grimm. "A Simple Guide for Generating BAC Transgenic Animals for Retinal Research". En Retinal Development, 109–22. New York, NY: Springer US, 2019. http://dx.doi.org/10.1007/978-1-0716-0175-4_9.

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Shi, Bu-Jun, J. Perry Gustafson y Peter Langridge. "A Simple TAE-Based Method to Generate Large Insert BAC Libraries from Plant Species". En Plant Genomics, 57–80. Totowa, NJ: Humana Press, 2009. http://dx.doi.org/10.1007/978-1-59745-427-8_4.

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House, Terry C. "Client Server Access: Wired vs. Wireless LEO Satellite-ATM Connectivity; A (MS-Ro-BAC) Experiment". En Computational Intelligence and Security, 719–24. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/11596981_105.

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Hughes, Graham R. V. "A Bad Back……". En Understanding Hughes Syndrome, 67. London: Springer London, 2009. http://dx.doi.org/10.1007/978-1-84800-376-7_39.

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Maclean, Rupert, Shanti Jagannathan y Brajesh Panth. "A Holistic Approach to Greening TVET: A Case Study and Analysis of Bac Thang Long Economic Technical College Practices in Viet Nam". En Technical and Vocational Education and Training: Issues, Concerns and Prospects, 99–117. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-6559-0_5.

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Vesanen, Teemu, Jari Shemeikka, Kostas Tsatsakis, Brian O’Regan, Andriy Hryshchenko, Eoin O’Leidhin y Dominic O’Sullivan. "Digital Tools for HVAC-Design, Operation and Efficiency Management". En Innovative Tools and Methods Using BIM for an Efficient Renovation in Buildings, 63–73. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-04670-4_5.

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AbstractThe project BIM4EEB aims also to develop digital tools to support the design, procurement, installation, post-renovation operation, user feedback and profiling of building automation systems for HVAC. This helps supporting decision making, interaction with tenants and owners during the design, construction, and post-renovation operation phases. The development of the tools will be underpinned by a sound methodological approach. Work will include considerations of interoperability with Smart City technology of automation systems for HVAC. Specific objectives will be related to the development of the following software tools: A software component supporting the automatic generation of the layout for control systems emphasising on user preferences and including constraint checking of BAC-topologies against selected building codes. Data and information stored in BIM models are used to generate the initial recommendations and constraints and to deliver the final installation instructions. A software component allowing the seamless specification and evaluation of user comfort and systems performance. The underpinning information model will merge data sources from BIM (dimensional data) and BAC (factual data). An energy-refurbishment assessment tool, for bridging the gap between commercial simulators and the BIM management system. A user-profiling component allowing to compare expectations of tenants and owners regarding comfort and systems’ performance against monitored parameters. The results of this software component can be used in the pre- and post-renovation phases to update the content of BIM systems and thus to improve their accuracy and to reduce efforts for data acquisition and verification.
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Kim, Tran Thi, Nguyen Thi Thu Hong, Nguyen Khac Thanh Long, Nguyen Ky Phung y Nguyen Thi Bay. "Mapping Tidal Harmonic Constant Map from Vung Tau – Bac Lieu, Viet Nam by Using a Numerical Model in Curvilinear Coordinate". En Lecture Notes in Civil Engineering, 701–9. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-3303-5_63.

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Dagnes, Alison. "Who Brings the Funny?" En A Conservative Walks Into a Bar, 1–40. New York: Palgrave Macmillan US, 2012. http://dx.doi.org/10.1057/9781137270344_1.

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Dagnes, Alison. "Data, Experiments, and Proof". En A Conservative Walks Into a Bar, 41–78. New York: Palgrave Macmillan US, 2012. http://dx.doi.org/10.1057/9781137270344_2.

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Actas de conferencias sobre el tema "BAC-A"

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Wu, Yonghui, Lan Liu, Timothy J. Close y Stefano Lonardi. "DECONVOLUTING THE BAC-GENE RELATIONSHIPS USING A PHYSICAL MAP". En Proceedings of the CSB 2007 Conference. PUBLISHED BY IMPERIAL COLLEGE PRESS AND DISTRIBUTED BY WORLD SCIENTIFIC PUBLISHING CO., 2007. http://dx.doi.org/10.1142/9781860948732_0023.

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Asmaa, Kassid y Elkamoun Najib. "A Comparative approach of different Or-BAC extensions: Application and limits". En 2014 5th Workshop on Codes, Cryptography and Communication Systems (WCCCS). IEEE, 2014. http://dx.doi.org/10.1109/wcccs.2014.7107922.

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Ippolito, M. G., D. La Cascia, G. Zizzo, A. Dinolfo y J. A. Sa'ed. "The BAC factor method: Application to a real italian not-residential building". En 2016 IEEE 16th International Conference on Environment and Electrical Engineering (EEEIC). IEEE, 2016. http://dx.doi.org/10.1109/eeeic.2016.7555495.

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Jeber, Jalal N., Maher Ahmed Abed y Ausama Abbas Faisal. "On-site detection of saliva-alcohol as a function of blood alcohol concentration using colorimetric biosensor based on deposited Chromium (VII) Oxide Nanoparticles on filter paper". En The 8th International Conference of Biotechnology, Environment and Engineering Sciences. SRO media, 2020. http://dx.doi.org/10.46617/icbe8003.

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Alcohol intoxication is usually associated with drowning, falls, overdoses, fires, occupational accidents, physical and sexual abusements, domestic violence and traffic accidents. Therefore, alcohol considered an important factor for the explanation of the occurrence of many types of injuries. For many purposes such as forensic, it is important to establish a detection method to ensure whether the subject or the patient have consumed alcohol at a level that would be the reason for the accidents or injuries occur. Therefore, in this work, a simple, rapid and low-cost method was developed and validated for the detection of the alcohol in saliva as a function of blood alcohol concentration (BAC). The method is based on fabricated a biosensor consisted of chromium oxide nanoparticles deposited on filter paper. The validation of the biosensor was tested on 50 participants which categories into two selected groups (1 and 2). Group 1 consisted of 20 subjects from an organized party (no alcohol), they usually consumed three to four drinks as an average per week while Group 2 consisted of 30 subjects from an organized party the local bar (alcohol group), usually consumed two to three drinks per day. The results of the present study have shown that 95% of group 1 demonstrated positive results with variable colour intensities of the BAC in comparison to the 80% only of subjects from group 2. The present study has approved that the fabricated biosensor can effectively detect 0.02% or more of BAC which can be a useful test for many purposes such as medical, forensic, research and workplace.
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Yatao Yang y B. Stiller. "A non-repudiation scheme for user postings based on BAC in Mesh networks". En 2012 IEEE/IFIP Network Operations and Management Symposium (NOMS 2012). IEEE, 2012. http://dx.doi.org/10.1109/noms.2012.6212048.

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Eren, Yavuz, Constantinos Mavroidis y Jason Nikitczuk. "B-Spline Based Adaptive Control of Shape Memory Alloy Actuated Robotic Systems". En ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-33425.

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In this paper we present a novel controller for Shape Memory Alloy (SMA) actuated robotic systems. The new controller, called BAC (B-spline based Adaptive Control), is based on a hybrid combination of gain scheduling, B-spline approximation, variable structure control and integral control. The proposed controller shows excellent positioning accuracy and speed throughout the full range of motion of a SMA actuated robotic system in large-scale applications. To demonstrate the validity of BAC, a novel anthropomorphic SMA Actuated forearm/wrist mechanism is utilized in real-time PC based control experiments. BAC is experimentally compared to PID and integral variable structure controllers and it is shown that its performance is superior.
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Beccali, Marco, Marina Bonomolo y Gaetano Zizzo. "Definition and Assessment of a BAC Factor for Estimating Electrical Consumption of Outdoor Lighting". En 2018 IEEE International Conference on Environment and Electrical Engineering and 2018 IEEE Industrial and Commercial Power Systems Europe (EEEIC / I&CPS Europe). IEEE, 2018. http://dx.doi.org/10.1109/eeeic.2018.8494617.

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Chung, SungHak. "Development of BAC Consumption and Related Structure Equation Model on Korean Driver". En Applied Human Factors and Ergonomics Conference. AHFE International, 2018. http://dx.doi.org/10.54941/10022.

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This study is to provide the criteria necessary for justification on any administrative measure possible to revoke ones driving license or to legally punish any person who has been under the influence whilst driving. The alcohol concentration in blood/breath was measured in this research through the drinking culture habits. The conclusion of this study estimates per hour, the average consumption rate of BAC (β) -0.0178g/kg and SD was 0.00497. Then, a consumption rate of the BAC will be calculated out through the multiple regression analysis thereof. A structural equation model of the effect that the drinking culture habit and the consumption rate of the BAC have on unsafe human behavior tendency factor is expressed in a model. In this study, a questionnaire on behavioral response whilst under alcohol influence, physical characteristics and personality test was conducted, also included was the alcohol test of NHTSA and the WHO alcohol test.
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Koulouris, Andreas, Allan Clark, Andrew Hart y Leo Alexandre. "P289 Best analgesia control in pancreatic adeno – carcinoma (the BAC-PAC study)- a prospective cohort study". En Abstracts of the BSG Annual Meeting, 20–23 June 2022. BMJ Publishing Group Ltd and British Society of Gastroenterology, 2022. http://dx.doi.org/10.1136/gutjnl-2022-bsg.342.

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Da Silva, Pedro Raposeiro, Sara Almeida Santos y Jorge De Brito. "Comportamento mecânico de betão auto-compactável produzido com agregados reciclados provenientes da indústria de pré-fabricação". En HAC2018 - V Congreso Iberoamericano de Hormigón Autocompactable y Hormigones Especiales. Valencia: Universitat Politècnica València, 2018. http://dx.doi.org/10.4995/hac2018.2018.5299.

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Actualmente, devido à crise económica e às exigências de desenvolvimento sustentável, a tecnologia do betão requer uma nova abordagem, baseada essencialmente em três vectores: métodos de produção e colocação com menor consumo de energia, aumento da durabilidade das estruturas e maior taxa de reciclagem de materiais, nomeadamente através da sua reintrodução (reutilização) no processo de construção. O uso de betão autocompactável (BAC) e a incorporação de agregados reciclados na produção de argamassas e de betão são soluções com grande potencial, particularmente para a indústria de pré-fabricação, na qual os requisitos do produto final são maiores. Por esta razão, os resíduos desta indústria são também aqueles com maior potencial para serem utilizados como agregados reciclados (AR) de alta qualidade na produção de novos elementos de betão. Seguindo esta linha de raciocínio, este artigo pretende avaliar a viabilidade de reintrodução de agregados reciclados de betão na indústria de pré-fabricação. Desse modo, foram avaliadas as propriedades mecânicas do BAC com incorporação de AR (grossos e finos - AGG e AFR) a partir de elementos pré-fabricados triturados. A intenção foi avaliar a capacidade de produção de BAC com um desempenho mínimo pré-estabelecido em termos de resistência mecânica, incorporando diferentes percentagens de AR (AFR / AGR% 25/25%, 50/50%, 0/100% 0%) produzidos a partir de betão pré-fabricado com desempenho alvo semelhante. Esta avaliação foi feita para duas classes de resistência (45 MPa e 65 MPa), com a intenção de obter como resultado final betão com agregados reciclados cujas características fossem compatíveis com as de um BAC com agregados naturais, em termos de trabalhabilidade e resistência mecânica. Também se pretendeu avaliar a influência da incorporação de agregados finos e grossos nas propriedades mecânicas do betão. O principal objectivo desta investigação foi proporcionar à indústria de pré-fabricação uma forma inovadora de eliminação e recuperação de resíduos auto-gerados, minimizando o consumo de recursos naturais e, consequentemente, reduzindo significativamente seu impacto ambiental. Além dos aspectos ambientais, há também aspectos económicos associados, já que este procedimento reduz os custos de compra e transporte dos materiais.Os resultados permitiram estabelecer conclusões sobre os BAC produzidos com agregados finos e grossos reciclados da indústria de pré-fabricação, com base nas suas propriedades mecânicas. As propriedades estudadas são fortemente afectadas pelo tipo e quantidade de agregados reciclados. É enfatizado o potencial demonstrado, principalmente no estado endurecido, pelo uso conjunto de agregados finos e grossos reciclados.DOI: http://dx.doi.org/10.4995/HAC2018.2018.ID.5299
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Informes sobre el tema "BAC-A"

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Zhang, Hongbin, Shahal Abbo, Weidong Chen, Amir Sherman, Dani Shtienberg y Frederick Muehlbauer. Integrative Physical and Genetic Mapping of the Chickpea Genome for Fine Mapping and Analysis of Agronomic Traits. United States Department of Agriculture, marzo de 2010. http://dx.doi.org/10.32747/2010.7592122.bard.

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Chickpea is the third most important pulse crop in the world and ranks first in the Middle East; however, it has been subjected to only limited research in modern genomics. In the first period of this project (US-3034-98R) we constructed two large-insert BAC and BIBAC libraries, developed 325 SSR markers and mapped QTLs controlling ascochyta blight resistance (ABR) and days to first flower (DTF). Nevertheless, the utilities of these tools and results in gene discovery and marker-assisted breeding are limited due to the absence of an essential platform. The goals of this period of the project were to use the resources and tools developed in the first period of the project to develop a BAC/BIBAC physical map for chickpea and using it to identify BAC/BIBACcontigs containing agronomic genes of interest, with an emphasis on ABR and DTF, and develop DNA markers suitable for marker-assisted breeding. Toward these goals, we proposed: 1) Fingerprint ~50,000 (10x) BACs from the BAC and BIBAC libraries, assemble the clones into a genome-wide BAC/BIBAC physical map, and integrate the BAC/BIBAC map with the existing chickpea genetic maps (Zhang, USA); 2) fine-map ABR and DTFQTLs and enhance molecular tools for chickpea genetics and breeding (Shahal, Sherman and DaniShtienberg, Israel; Chen and Muehlbauer; USA); and 3) integrate the BAC/BIBAC map with the existing chickpea genetic maps (Sherman, Israel; Zhang and Chen, USA). For these objectives, a total of $460,000 was requested originally, but a total of $300,000 was awarded to the project. We first developed two new BAC and BIBAC libraries, Chickpea-CME and Chickpea- CHV. The chickpea-CMEBAC library contains 22,272 clones, with an average insert size of 130 kb and equivalent to 4.0 fold of the chickpea genome. The chickpea-CHVBIBAC library contains 38,400 clones, with an average insert size of 140 kb and equivalent to 7.5 fold of the chickpea genome. The two new libraries (11.5 x), along with the two BAC (Chickpea-CHI) and BIBAC (Chickpea-CBV) libraries (7.1 x) constructed in the first period of the project, provide libraries essential for chickpea genome physical mapping and many other genomics researches. Using these four libraries we then developed the proposed BAC/BIBAC physical map of chickpea. A total of 67,584 clones were fingerprinted, and 64,211 (~11.6 x) of the fingerprints validated and used in the physical map assembly. The physical map consists of 1,945 BAC/BIBACcontigs, with each containing an average of 39.2 clones and having an average physical length of 559 kb. The contigs collectively span ~1,088 Mb, being 1.49 fold of the 740- Mb chickpea genome. Third, we integrated the physical map with the two existing chickpea genetic maps using a total of 172 (124 + 48) SSR markers. Fourth, we identified tightly linked markers for ABR-QTL1, increased marker density at ABR-QTL2 and studied the genetic basis of resistance to pod abortion, a major problem in the east Mediterranean, caused by heat stress. Finally, we, using the integrated map, isolated the BAC/BIBACcontigs containing or closely linked to QTL4.1, QTL4.2 and QTL8 for ABR and QTL8 for DTF. The integrated BAC/BIBAC map resulted from the project will provide a powerful platform and tools essential for many aspects of advanced genomics and genetics research of this crop and related species. These includes, but are not limited to, targeted development of SNP, InDel and SSR markers, high-resolution mapping of the chickpea genome and its agronomic genes and QTLs, sequencing and decoding of all genes of the genome using the next-generation sequencing technology, and comparative genome analysis of chickpea versus other legumes. The DNA markers and BAC/BIBACcontigs containing or closely linked to ABR and DTF provide essential tools to develop SSR and SNP markers well-suited for marker-assisted breeding of the traits and clone their corresponding genes. The development of the tools and knowledge will thus promote enhanced and substantial genetic improvement of the crop and related legumes.
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Zhang, Hongbin B., David J. Bonfil y Shahal Abbo. Genomics Tools for Legume Agronomic Gene Mapping and Cloning, and Genome Analysis: Chickpea as a Model. United States Department of Agriculture, marzo de 2003. http://dx.doi.org/10.32747/2003.7586464.bard.

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The goals of this project were to develop essential genomic tools for modern chickpea genetics and genomics research, map the genes and quantitative traits of importance to chickpea production and generate DNA markers that are well-suited for enhanced chickpea germplasm analysis and breeding. To achieve these research goals, we proposed the following research objectives in this period of the project: 1) Develop an ordered BAC library with an average insert size of 150 - 200 kb (USA); 2) Develop 300 simple sequence repeat (SSR) markers with an aid of the BAC library (USA); 3) Develop SSR marker tags for Ascochyta response, flowering date and grain weight (USA); 4) Develop a molecular genetic map consisting of at least 200 SSR markers (Israel and USA); 5) Map genes and QTLs most important to chickpea production in the U.S. and Israel: Ascochyta response, flowering and seed set date, grain weight, and grain yield under extreme dryland conditions (Israel); and 6) Determine the genetic correlation between the above four traits (Israel). Chickpea is the third most important pulse crop in the world and ranks the first in the Middle East. Chickpea seeds are a good source of plant protein (12.4-31.5%) and carbohydrates (52.4-70.9%). Although it has been demonstrated in other major crops that the modern genetics and genomics research is essential to enhance our capacity for crop genetic improvement and breeding, little work was pursued in these research areas for chickpea. It was absent in resources, tools and infrastructure that are essential for chickpea genomics and modern genetics research. For instance, there were no large-insert BAC and BIBAC libraries, no sufficient and user- friendly DNA markers, and no intraspecific genetic map. Grain sizes, flowering time and Ascochyta response are three main constraints to chickpea production in drylands. Combination of large seeds, early flowering time and Ascochyta blight resistance is desirable and of significance for further genetic improvement of chickpea. However, it was unknown how many genes and/or loci contribute to each of the traits and what correlations occur among them, making breeders difficult to combine these desirable traits. In this period of the project, we developed the resources, tools and infrastructure that are essential for chickpea genomics and modern genetics research. In particular, we constructed the proposed large-insert BAC library and an additional plant-transformation-competent BIBAC library from an Israeli advanced chickpea cultivar, Hadas. The BAC library contains 30,720 clones and has an average insert size of 151 kb, equivalent to 6.3 x chickpea haploid genomes. The BIBAC library contains 18,432 clones and has an average insert size of 135 kb, equivalent to 3.4 x chickpea haploid genomes. The combined libraries contain 49,152 clones, equivalent to 10.7 x chickpea haploid genomes. We identified all SSR loci-containing clones from the chickpea BAC library, generated sequences for 536 SSR loci from a part of the SSR-containing BACs and developed 310 new SSR markers. From the new SSR markers and selected existing SSR markers, we developed a SSR marker-based molecular genetic map of the chickpea genome. The BAC and BIBAC libraries, SSR markers and the molecular genetic map have provided essential resources and tools for modern genetic and genomic analyses of the chickpea genome. Using the SSR markers and genetic map, we mapped the genes and loci for flowering time and Ascochyta responses; one major QTL and a few minor QTLs have been identified for Ascochyta response and one major QTL has been identified for flowering time. The genetic correlations between flowering time, grain weight and Ascochyta response have been established. These results have provided essential tools and knowledge for effective manipulation and enhanced breeding of the traits in chickpea.
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Lim, C. S., R. X. Xu y M. Wang. Construction of a genome-wide human BAC-Unigene resource. Final progress report, 1989--1996. Office of Scientific and Technical Information (OSTI), diciembre de 1996. http://dx.doi.org/10.2172/656464.

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Kwan, Johnson, Adolf Baumgartner, Chun-Mei Lu, Mei Wang, Jingly F. Weier, Horst F. Zitzelsberger y Heinz-Ulrich G. Weier. BAC-FISH assays delineate complex chromosomal rearrangements in a case of post-Chernobyl childhood thyroid cancer. Office of Scientific and Technical Information (OSTI), marzo de 2009. http://dx.doi.org/10.2172/983040.

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Dubcovsky, Jorge, Tzion Fahima y Ann Blechl. Positional cloning of a gene responsible for high grain protein content in tetraploid wheat. United States Department of Agriculture, septiembre de 2003. http://dx.doi.org/10.32747/2003.7695875.bard.

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High Grain Protein Content (GPC) is a desirable trait in breadmaking and pasta wheat varieties because of its positive effects on quality and nutritional value. However, selection for GPC is limited by our poor understanding of the genes involved in the accumulation of protein in the grain. The long-term goal of this project is to provide a better understanding of the genes controlling GPC in wheat. The specific objectives of this project were: a) to develop a high-density genetic map of the GPC gene in tetraploid wheat, b) to construct a T. turgidum Bacterial Artificial Chromosome (BAC) library, c) to construct a physical map of the GPC gene and identify a candidate for the GPC gene. A gene with a large effect on GPC was detected in Triticum turgidum var. dicoccoides and was previously mapped in the short arm of chromosome 6B. To define better the position of the Gpc-B1 locus we developed homozygous recombinant lines with recombination events within the QTL region. Except for the 30-cM region of the QTL these RSLs were isogenic for the rest of the genome minimizing the genetic variability. To minimize the environmental variability the RSLs were characterized using 10 replications in field experiments organized in a Randomized Complete Block Design, which were repeated three times. Using this strategy, we were able to map this QTL as a single Mendelian locus (Gpc-B1) on a 2.6-cM region flanked by RFLP markers Xcdo365 and Xucw67. All three experiments showed that the lines carrying the DIC allele had an average absolute increase in GPC of 14 g/kg. Using the RFLP flanking markers, we established the microcolinearity between a 2.l-cM region including the Gpc-B1 gene in wheat chromosome 6BS and a 350-kb region on rice chromosome 2. Rice genes from this region were used to screen the Triticeae EST collection, and these ESTs were used to saturate the Gpc-B1 region with molecular markers. With these new markers we were able to map the Gpc-B1 locus within a 0.3-cM region flanked by PCR markers Xucw83 and Xucw71. These flanking markers defined a 36-kb colinear region with rice, including one gene that is a potential candidate for the Gpc-B1 gene. To develop a physical map of the Gpc-B1 region in wheat we first constructed a BAC library of tetraploid wheat, from RSL#65 including the high Gpc-B1 allele. We generated half- million clones with an average size of l3l-kb (5.1 X genome equivalents for each of the two genomes). This coverage provides a 99.4% probability of recovering any gene from durum wheat. We used the Gpc-BI flanking markers to screen this BAC library and then completed the physical map by chromosome walking. The physical map included two overlapping BACs covering a region of approximately 250-kb, including two flanking markers and the Gpc-B1 gene. Efforts are underway to sequence these two BACs to determine if additional wheat genes are present in this region. Weare also developing new RSLs to further dissect this region. We developed PCR markers for flanking loci Xucw79andXucw71 to facilitate the introgression of this gene in commercial varieties by marker assisted selection (httQ://maswheat.ucdavis.edu/ orotocols/HGPC/index.hlm). Using these markers we introgressed the Gpc-B1 gene in numerous pasta and common wheat breeding lines.
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Medrano, Juan, Adam Friedmann, Moshe (Morris) Soller, Ehud Lipkin y Abraham Korol. High resolution linkage disequilibrium mapping of QTL affecting milk production traits in Israel Holstein dairy cattle. United States Department of Agriculture, marzo de 2008. http://dx.doi.org/10.32747/2008.7696509.bard.

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Original objectives: To create BAC contigs covering two QTL containing chromosomal regions (QTLR) and obtain BAC end sequence information as a platform for SNP identification. Use the SNPs to search for marker-QTL linkage disequilibrium (LD) in the test populations (US and Israel Holstein cattle). Identify candidate genes, test for association with dairy cattle production and functional traits, and confirm any associations in a secondary test population. Revisions in the course of the project: The selective recombinant genotyping (SRG) methodology which we implemented to provide moderate resolution QTL mapping turned out to be less effective than expected, due to problems introduced by incomplete marker informativity. This required a no-cost one-year extension of the project. Aside from this, the project was implemented essentially as envisaged, but only with respect to a single QTLR and single population association-test. Background to the topic. Dairy cattle breeders are looking to marker-assisted selection (MAS) as a means of identifying genetically superior sires and dams. MAS based on population-wide LD can be many times more effective than MAS based on within-family linkage mapping. In this proposal we developed a protocol leading from family based QTL mapping to population-wide LD between markers and the QTL Major conclusions, solutions, achievements. The critical importance of marker informativity for application of the SRG design in outcrossing random mating populations was identified, and an alternative Fractioned Pool Design (FPD) based on selective DNA pooling was developed. We demonstrated the feasibility of constructing a BAC contig across a targeted chromosomal region flanking the marker RM188 on bovine chromosome BTA4, which was shown in previous work to contain a QTL affecting milk production traits. BAC end sequences were obtained and successfully screened for SNPs. LD studies of these SNPs in the Israel population, and of an independent set of SNPs taken across the entire proximal region of BTA4 in the USA population, showed a much lower degree of LD than previously reported in the literature. Only at distances in the sub-cM level did an appreciable fraction of SNP marker-pairs show levels of LD useful for MAS. In contrast, studies in the Israel population using microsatellite markers, presented an equivalent degree of LD at a 1-5 separation distance. SNP LD appeared to reflect historical population size of Bostaurus (Ne=5000- 10,000), while microsatellite LD appeared to be in proportion to more recent effective population size of the Holstein breed (Ne=50-100). An appreciable fraction of the observed LD was due to Family admixture structure of the Holstein population. The SNPs MEOX2/IF2G (found within the gene SETMAR at 23,000 bp from RM188) and SNP23 were significantly associated with PTA protein, Cheese dollars and Net Merit Protein in the Davis bull resource population, and were also associated with protein and casein percentages in the Davis cow resource population. Implications. These studies document a major difference in degree of LD presented by SNPs as compared to microsatellites, and raise questions as to the source of this difference and its implications for QTL mapping and MAS. The study lends significant support to the targeted approach to fine map a previously identified QTL. Using high density genotyping with SNP discovered in flanking genes to the QTL, we have identified important markers associated with milk protein percentage that can be tested in markers assisted selection programs.
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Ebata, Ayako, Khue Minh Nguyen, Minh Hanh Nguyen y Thi Dien Nguyen. How Did Covid-19 Affect Food and Nutrition Security of Migrant Workers in Northern Vietnam? Institute of Development Studies, junio de 2022. http://dx.doi.org/10.19088/ids.2022.043.

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This study explored how measures to curtail the spread of the coronavirus (Covid-19) in Vietnam affected the livelihoods and food and nutrition security of internal migrant workers. While Vietnam has made impressive progress towards food security in the past decades, marginalised groups of people such as ethnic minorities and migrants continue to face significant challenges. The project team investigated how the pandemic affected the precarity of these groups’ income-generating opportunities and how the level of income generated affected the quality, as well as the quantity, of food consumed by migrant workers in Hanoi, the capital, and the Bac Ninh province, which hosts large industrial zones. Our research shows that income for migrant workers significantly reduced as a result of Covid-19-related lockdown measures.
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Fahima, Tzion y Jorge Dubcovsky. Map-based cloning of the novel stripe rust resistance gene YrG303 and its use to engineer 1B chromosome with multiple beneficial traits. United States Department of Agriculture, enero de 2013. http://dx.doi.org/10.32747/2013.7598147.bard.

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Research problem: Bread wheat (Triticumaestivum) provides approximately 20% of the calories and proteins consumed by humankind. As the world population continues to increase, it is necessary to improve wheat yields, increase grain quality, and minimize the losses produced by biotic and abiotic stresses. Stripe rust, caused by Pucciniastriiformisf. sp. tritici(Pst), is one of the most destructive diseases of wheat. The new pathogen races are more virulent and aggressive than previous ones and have produced large economic losses. A rich source for stripe-rust resistance genes (Yr) was found in wild emmer wheat populations from Israel. Original Project goals: Our long term goal is to identify, map, clone, characterize and deploy in breeding, novel wild emmer Yr genes, and combine them with multiple beneficial traits. The current study was aiming to map and clone YrG303 and Yr15, located on chromosome 1BS and combine them with drought resistance and grain quality genes. Positional cloning of YrG303/Yr15: Fine mapping of these genes revealed that YrG303 is actually allelic to Yr15. Fine genetic mapping using large segregating populations resulted in reduction of the genetic interval spanning Yr15 to less than 0.1 cM. Physical mapping of the YrG303/Yr15 locus was based on the complete chromosome 1BS physical map of wheat constructed by our group. Screening of 1BS BAC library with Yr15 markers revealed a long BAC scaffold covering the target region. The screening of T. dicoccoidesaccession-specific BAC library with Yr15 markers resulted in direct landing on the target site. Sequencing of T. dicoccoidesBAC clones that cover the YrG303/Yr15 locus revealed a single candidate gene (CG) with conserved domains that may indicate a role in disease resistance response. Validation of the CG was carried out using EMS mutagenesis (loss-of- function approach). Sequencing of the CG in susceptible yr15/yrG303 plants revealed three independent mutants that harbour non-functional yr15/yrG303 alleles within the CG conserved domains, and therefore validated its function as a Pstresistance gene. Evaluation of marker-assisted-selection (MAS) for Yr15. Introgressions of Yr15 into cultivated wheat are widely used now. Recently, we have shown that DNA markers linked to Yr15 can be used as efficient tools for introgression of Yr15 into cultivated wheat via MAS. The developed markers were consistent and polymorphic in all 34 tested introgressions and are the most recommended markers for the introgression of Yr15. These markers will facilitate simultaneous selection for multiple Yr genes and help to avoid escapees during the selection process. Engineering of improved chromosome 1BS that harbors multiple beneficial traits. We have implemented the knowledge and genetic resources accumulated in this project for the engineering of 1B "super-chromosome" that harbors multiple beneficial traits. We completed the generation of a chromosome including the rye 1RS distal segment associated with improved drought tolerance with the Yr gene, Yr15, and the strong gluten allele 7Bx-over-expressor (7Bxᴼᴱ). We have completed the introgression of this improved chromosome into our recently released variety Patwin-515HP and our rain fed variety Kern, as well as to our top breeding lines UC1767 and UC1745. Elucidating the mechanism of resistance exhibited by Yr36 (WKS1). The WHEAT KINASE START1 (WKS1) resistance gene (Yr36) confers partial resistance to Pst. We have shown that wheat plants transformed with WKS1 transcript are resistant to Pst. WKS1 is targeted to the chloroplast where it phosphorylates the thylakoid-associatedascorbateperoxidase (tAPX) and reduces its ability to detoxify peroxides. Based on these results, we propose that the phosphorylation of tAPX by WKS1 reduces the ability of the cells to detoxify ROS and contributes to cell death. Distribution and diversity of WKS in wild emmer populations. We have shown that WKS1 is present only in the southern distribution range of wild emmer in the Fertile Crescent. Sequence analysis revealed a high level of WKS1 conservation among wild emmer populations, in contrast to the high level of diversity observed in NB-LRR genes. This phenomenon shed some light on the evolution of genes that confer partial resistance to Pst. Three new WKS1 haplotypes displayed a resistance response, suggesting that they can be useful to improve wheat resistance to Pst. In summary, we have improved our understanding of cereals’ resistance mechanisms to rusts and we have used that knowledge to develop improved wheat varieties.
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9

Weller, Joel I., Harris A. Lewin y Micha Ron. Determination of Allele Frequencies for Quantitative Trait Loci in Commercial Animal Populations. United States Department of Agriculture, febrero de 2005. http://dx.doi.org/10.32747/2005.7586473.bard.

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Individual loci affecting economic traits in dairy cattle (ETL) have been detected via linkage to genetic markers by application of the granddaughter design in the US population and the daughter design in the Israeli population. From these analyses it is not possible to determine allelic frequencies in the population at large, or whether the same alleles are segregating in different families. We proposed to answer this question by application of the "modified granddaughter design", in which granddaughters with a common maternal grandsire are both genotyped and analyzed for the economic traits. The objectives of the proposal were: 1) to fine map three segregating ETL previously detected by a daughter design analysis of the Israeli dairy cattle population; 2) to determine the effects of ETL alleles in different families relative to the population mean; 3) for each ETL, to determine the number of alleles and allele frequencies. The ETL on Bostaurusautosome (BT A) 6 chiefly affecting protein concentration was localized to a 4 cM chromosomal segment centered on the microsatellite BM143 by the daughter design. The modified granddaughter design was applied to a single family. The frequency of the allele increasing protein percent was estimated at 0.63+0.06. The hypothesis of equal allelic frequencies was rejected at p<0.05. Segregation of this ETL in the Israeli population was confirmed. The genes IBSP, SPP1, and LAP3 located adjacent to BM143 in the whole genome cattle- human comparative map were used as anchors for the human genome sequence and bovine BAC clones. Fifteen genes within 2 cM upstream of BM143 were located in the orthologous syntenic groups on HSA4q22 and HSA4p15. Only a single gene, SLIT2, was located within 2 cM downstream of BM143 in the orthologous HSA4p15 region. The order of these genes, as derived from physical mapping of BAC end sequences, was identical to the order within the orthologous syntenic groups on HSA4: FAM13A1, HERC3. CEB1, FLJ20637, PP2C-like, ABCG2, PKD2. SPP, MEP, IBSP, LAP3, EG1. KIAA1276, HCAPG, MLR1, BM143, and SLIT2. Four hundred and twenty AI bulls with genetic evaluations were genotyped for 12 SNPs identified in 10 of these genes, and for BM143. Seven SNPs displayed highly significant linkage disequilibrium effects on protein percentage (P<0.000l) with the greatest effect for SPP1. None of SNP genotypes for two sires heterozygous for the ETL, and six sires homozygous for the ETL completely corresponded to the causative mutation. The expression of SPP 1 and ABCG2 in the mammary gland corresponded to the lactation curve, as determined by microarray and QPCR assays, but not in the liver. Anti-sense SPP1 transgenic mice displayed abnormal mammary gland differentiation and milk secretion. Thus SPP 1 is a prime candidate gene for this ETL. We confirmed that DGAT1 is the ETL segregating on BTA 14 that chiefly effects fat concentration, and that the polymorphism is due to a missense mutation in an exon. Four hundred Israeli Holstein bulls were genotyped for this polymorphism, and the change in allelic frequency over the last 20 years was monitored.
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Choudhary, Ruplal, Victor Rodov, Punit Kohli, Elena Poverenov, John Haddock y Moshe Shemesh. Antimicrobial functionalized nanoparticles for enhancing food safety and quality. United States Department of Agriculture, enero de 2013. http://dx.doi.org/10.32747/2013.7598156.bard.

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Original objectives The general goal of the project was to utilize the bactericidal potential of curcumin- functionalizednanostructures (CFN) for reinforcement of food safety by developing active antimicrobial food-contact surfaces. In order to reach the goal, the following secondary tasks were pursued: (a) further enhancement of the CFN activity based on understanding their mode of action; (b) preparing efficient antimicrobial surfaces, investigating and optimizing their performance; (c) testing the efficacy of the antimicrobial surfaces in real food trials. Background to the topic The project dealt with reducing microbial food spoilage and safety hazards. Cross-contamination through food-contact surfaces is one of the major safety concerns, aggravated by bacterial biofilm formation. The project implemented nanotech methods to develop novel antimicrobial food-contact materials based on natural compounds. Food-grade phenylpropanoidcurcumin was chosen as the most promising active principle for this research. Major conclusions, solutions, achievements In agreement with the original plan, the following research tasks were performed. Optimization of particles structure and composition. Three types of curcumin-functionalizednanostructures were developed and tested: liposome-type polydiacetylenenanovesicles, surface- stabilized nanoparticles and methyl-β-cyclodextrin inclusion complexes (MBCD). The three types had similar minimal inhibitory concentration but different mode of action. Nanovesicles and inclusion complexes were bactericidal while the nanoparticlesbacteriostatic. The difference might be due to different paths of curcumin penetration into bacterial cell. Enhancing the antimicrobial efficacy of CFN by photosensitization. Light exposure strengthened the bactericidal efficacy of curcumin-MBCD inclusion complexes approximately three-fold and enhanced the bacterial death on curcumin-coated plastic surfaces. Investigating the mode of action of CFN. Toxicoproteomic study revealed oxidative stress in curcumin-treated cells of E. coli. In the dark, this effect was alleviated by cellular adaptive responses. Under light, the enhanced ROS burst overrode the cellular adaptive mechanisms, disrupted the iron metabolism and synthesis of Fe-S clusters, eventually leading to cell death. Developing industrially-feasible methods of binding CFN to food-contact surfaces. CFN binding methods were developed for various substrates: covalent binding (binding nanovesicles to glass, plastic and metal), sonochemical impregnation (binding nanoparticles to plastics) and electrostatic layer-by-layer coating (binding inclusion complexes to glass and plastics). Investigating the performance of CFN-coated surfaces. Flexible and rigid plastic materials and glass coated with CFN demonstrated bactericidal activity towards Gram-negative (E. coli) and Gram-positive (Bac. cereus) bacteria. In addition, CFN-impregnated plastic material inhibited bacterial attachment and biofilm development. Testing the efficacy of CFN in food preservation trials. Efficient cold pasteurization of tender coconut water inoculated with E. coli and Listeriamonocytogeneswas performed by circulation through a column filled with CFN-coated glass beads. Combination of curcumin coating with blue light prevented bacterial cross contamination of fresh-cut melons through plastic surfaces contaminated with E. coli or Bac. licheniformis. Furthermore, coating of strawberries with CFN reduced fruit spoilage during simulated transportation extending the shelf life by 2-3 days. Implications, both scientific and agricultural BARD Report - Project4680 Page 2 of 17 Antimicrobial food-contact nanomaterials based on natural active principles will preserve food quality and ensure safety. Understanding mode of antimicrobial action of curcumin will allow enhancing its dark efficacy, e.g. by targeting the microbial cellular adaptation mechanisms.
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