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Journal articles on the topic 'Origin'
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1
Toledo, Natalia, and Clare Sullivan. "Ra ruzulú guidxilayú / Origen / origin." World Literature Today 85, no. 1 (2011): 21. http://dx.doi.org/10.1353/wlt.2011.0165.
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Leslie, M. "ORIGINS: On the Origin of Photosynthesis." Science 323, no. 5919 (March 6, 2009): 1286–87. http://dx.doi.org/10.1126/science.323.5919.1286.
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Hoggard, Timothy, Erika Chacin, Allison J. Hollatz, Christoph F. Kurat, and Catherine A. Fox. "The budding yeast Fkh1 Forkhead associated (FHA) domain promotes a G1-chromatin state and the activity of chromosomal DNA replication origins." PLOS Genetics 20, no. 8 (August 5, 2024): e1011366. http://dx.doi.org/10.1371/journal.pgen.1011366.
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In Saccharomyces cerevisiae, the forkhead (Fkh) transcription factor Fkh1 (forkhead homolog) enhances the activity of many DNA replication origins that act in early S-phase (early origins). Current models posit that Fkh1 acts directly to promote these origins’ activity by binding to origin-adjacent Fkh1 binding sites (FKH sites). However, the post-DNA binding functions that Fkh1 uses to promote early origin activity are poorly understood. Fkh1 contains a conserved FHA (forkhead associated) domain, a protein-binding module with specificity for phosphothreonine (pT)-containing partner proteins. At a small subset of yeast origins, the Fkh1-FHA domain enhances the ORC (origin recognition complex)-origin binding step, the G1-phase event that initiates the origin cycle. However, the importance of the Fkh1-FHA domain to either chromosomal replication or ORC-origin interactions at genome scale is unclear. Here, S-phase SortSeq experiments were used to compare genome replication in proliferating FKH1 and fkh1-R80A mutant cells. The Fkh1-FHA domain promoted the activity of ≈ 100 origins that act in early to mid- S-phase, including the majority of centromere-associated origins, while simultaneously inhibiting ≈ 100 late origins. Thus, in the absence of a functional Fkh1-FHA domain, the temporal landscape of the yeast genome was flattened. Origins are associated with a positioned nucleosome array that frames a nucleosome depleted region (NDR) over the origin, and ORC-origin binding is necessary but not sufficient for this chromatin organization. To ask whether the Fkh1-FHA domain had an impact on this chromatin architecture at origins, ORC ChIPSeq data generated from proliferating cells and MNaseSeq data generated from G1-arrested and proliferating cell populations were assessed. Origin groups that were differentially regulated by the Fkh1-FHA domain were characterized by distinct effects of this domain on ORC-origin binding and G1-phase chromatin. Thus, the Fkh1-FHA domain controlled the distinct chromatin architecture at early origins in G1-phase and regulated origin activity in S-phase.
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Lim, Kenny, and Aron O’Cass. "Consumer brand classifications: an assessment of culture‐of‐origin versus country‐of‐origin." Journal of Product & Brand Management 10, no. 2 (April 1, 2001): 120–36. http://dx.doi.org/10.1108/10610420110388672.
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Examines consumers’ perception of brands as influenced by their origins and the differences in classification ability between consumers’ knowledge levels. Specifically, culture‐of‐brand‐origin (COBO) is proposed to have replaced country‐of‐origin (COO) as the most important origin influence regarded by consumers in their perceptions of brands. Culture‐of‐brand‐origin is used to mean the cultural origin or heritage of a brand. Data were gathered from 459 respondents in the Asian city of Singapore; and used to assess Singaporean consumers’ ability to classify the cultural origins of fashion clothing brands. This was compared to their ability to classify the country origins of the same brands. Six brands were used in a between‐subjects design, with three brands of western countries and three of eastern countries. Results indicate that consumers can more readily identify the cultural origin of brands over their country‐of‐origin. Reveals that a consumer’s ability to make this distinction is influenced by the consumer’s perception of how well he/she knows the brand.
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Spencer, Joshua, and Chris Tillman. "Necessity of origins and multi-origin art." Inquiry 62, no. 7 (May 8, 2018): 741–54. http://dx.doi.org/10.1080/0020174x.2018.1470567.
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Edler, Lutz, and Annette Kopp-Schneider. "Origins of the mutational origin of cancer." International Journal of Epidemiology 34, no. 5 (July 26, 2005): 1168–70. http://dx.doi.org/10.1093/ije/dyi134.
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Patel, Prasanta K., Benoit Arcangioli, Stephen P. Baker, Aaron Bensimon, and Nicholas Rhind. "DNA Replication Origins Fire Stochastically in Fission Yeast." Molecular Biology of the Cell 17, no. 1 (January 2006): 308–16. http://dx.doi.org/10.1091/mbc.e05-07-0657.
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DNA replication initiates at discrete origins along eukaryotic chromosomes. However, in most organisms, origin firing is not efficient; a specific origin will fire in some but not all cell cycles. This observation raises the question of how individual origins are selected to fire and whether origin firing is globally coordinated to ensure an even distribution of replication initiation across the genome. We have addressed these questions by determining the location of firing origins on individual fission yeast DNA molecules using DNA combing. We show that the firing of replication origins is stochastic, leading to a random distribution of replication initiation. Furthermore, origin firing is independent between cell cycles; there is no epigenetic mechanism causing an origin that fires in one cell cycle to preferentially fire in the next. Thus, the fission yeast strategy for the initiation of replication is different from models of eukaryotic replication that propose coordinated origin firing.
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Liu, Jun, Kristopher McConnell, Michael Dixon, and Brian R. Calvi. "Analysis of model replication origins in Drosophila reveals new aspects of the chromatin landscape and its relationship to origin activity and the prereplicative complex." Molecular Biology of the Cell 23, no. 1 (January 2012): 200–212. http://dx.doi.org/10.1091/mbc.e11-05-0409.
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Epigenetic regulation exerts a major influence on origins of DNA replication during development. The mechanisms for this regulation, however, are poorly defined. We showed previously that acetylation of nucleosomes regulates the origins that mediate developmental gene amplification during Drosophila oogenesis. Here we show that developmental activation of these origins is associated with acetylation of multiple histone lysines. Although these modifications are not unique to origin loci, we find that the level of acetylation is higher at the active origins and quantitatively correlated with the number of times these origins initiate replication. All of these acetylation marks were developmentally dynamic, rapidly increasing with origin activation and rapidly declining when the origins shut off and neighboring promoters turn on. Fine-scale analysis of the origins revealed that both hyperacetylation of nucleosomes and binding of the origin recognition complex (ORC) occur in a broad domain and that acetylation is highest on nucleosomes adjacent to one side of the major site of replication initiation. It was surprising to find that acetylation of some lysines depends on binding of ORC to the origin, suggesting that multiple histone acetyltransferases may be recruited during origin licensing. Our results reveal new insights into the origin epigenetic landscape and lead us to propose a chromatin switch model to explain the coordination of origin and promoter activity during development.
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Mora-Sánchez, Roberto de Jesús. "EDUCACIÓN SUPERIOR EN CENTROAMÉRICA. HIGHER EDUCATION IN CENTRAL AMERICA." Revista Electrónica Calidad en la Educación Superior 4, no. 1 (May 7, 2013): 187–98. http://dx.doi.org/10.22458/caes.v4i1.460.
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El presente artículo reseña el origen de la educación superior centroamericana desde sus comienzos hasta nuestros días. Se hace un breve recorrido por el origen de la educación superior, su devenir en América Latina y hasta el origen de la primera universidad centroamericana. Se exponen brevemente aquellos sucesos de orden político, económico o social de la época que influyeron en el surgimiento de la educación superior estatal en cada país de la región, así como los que determinaron el origen de la educación superior privada con sus promotores y detractores. Se expone el caso guatemalteco, hondureño, salvadoreño y nicaragüense y su evolución a nuestros días, así como los esfuerzos que han realizado los países de la región en procura de mejorar la calidad de la educación terciara que ofrecen las universidades públicas y privadas aquí establecidas.Palabras clave: Educación Superior, Educación Superior Pública, Educación Superior Privada, Universidades Públicas, Universidades Privadas, Origen de la Educación Superior, Centroamérica.AbstractThis article reviews the origins of American higher education since its inception to the present day. A brief tour of the origin of higher education, its evolution in Latin America and even the origin of the first American university. It outlines those events of a political, economic or social of the time that influenced the emergence of state higher education in each country of the region, as well as those for which the origin of private higher education with its proponents and detractors. We present the case of Guatemala, Honduras, El Salvador and Nicaragua and its evolution to the present day, as well as the efforts made by the countries of the region in an effort to improve the quality of tertiary education offered by public and private universities established herein. Keywords: Higher Education, Public Higher Education, Private Higher Education, Public Universities, Private Universities, Origin of Higher Education, Central America.
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Ciardo, Diletta, Olivier Haccard, Hemalatha Narassimprakash, Jean-Michel Arbona, Olivier Hyrien, Benjamin Audit, Kathrin Marheineke, and Arach Goldar. "Organization of DNA Replication Origin Firing in Xenopus Egg Extracts: The Role of Intra-S Checkpoint." Genes 12, no. 8 (August 9, 2021): 1224. http://dx.doi.org/10.3390/genes12081224.
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During cell division, the duplication of the genome starts at multiple positions called replication origins. Origin firing requires the interaction of rate-limiting factors with potential origins during the S(ynthesis)-phase of the cell cycle. Origins fire as synchronous clusters which is proposed to be regulated by the intra-S checkpoint. By modelling the unchallenged, the checkpoint-inhibited and the checkpoint protein Chk1 over-expressed replication pattern of single DNA molecules from Xenopus sperm chromatin replicated in egg extracts, we demonstrate that the quantitative modelling of data requires: (1) a segmentation of the genome into regions of low and high probability of origin firing; (2) that regions with high probability of origin firing escape intra-S checkpoint regulation and (3) the variability of the rate of DNA synthesis close to replication forks is a necessary ingredient that should be taken in to account in order to describe the dynamic of replication origin firing. This model implies that the observed origin clustering emerges from the apparent synchrony of origin firing in regions with high probability of origin firing and challenge the assumption that the intra-S checkpoint is the main regulator of origin clustering.
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Joshi, Ishita, Jie Peng, Gina Alvino, Elizabeth Kwan, and Wenyi Feng. "Exceptional origin activation revealed by comparative analysis in two laboratory yeast strains." PLOS ONE 17, no. 2 (February 14, 2022): e0263569. http://dx.doi.org/10.1371/journal.pone.0263569.
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We performed a comparative analysis of replication origin activation by genome-wide single-stranded DNA mapping in two yeast strains challenged by hydroxyurea, an inhibitor of the ribonucleotide reductase. We gained understanding of the impact on origin activation by three factors: S-phase checkpoint control, DNA sequence polymorphisms, and relative positioning of origin and transcription unit. Wild type W303 showed a significant reduction of fork progression accompanied by an elevated level of Rad53 phosphorylation as well as physical presence at origins compared to A364a. Moreover, a rad53K227A mutant in W303 activated more origins, accompanied by global reduction of ssDNA across all origins, compared to A364a. Sequence polymorphism in the consensus motifs of origins plays a minor role in determining strain-specific activity. Finally, we identified a new class of origins only active in checkpoint-proficient cells, which we named “Rad53-dependent origins”. Our study presents a comprehensive list of differentially used origins and provide new insights into the mechanisms of origin activation.
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Patel, Prasanta K., Naveen Kommajosyula, Adam Rosebrock, Aaron Bensimon, Janet Leatherwood, John Bechhoefer, and Nicholas Rhind. "The Hsk1(Cdc7) Replication Kinase Regulates Origin Efficiency." Molecular Biology of the Cell 19, no. 12 (December 2008): 5550–58. http://dx.doi.org/10.1091/mbc.e08-06-0645.
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Origins of DNA replication are generally inefficient, with most firing in fewer than half of cell cycles. However, neither the mechanism nor the importance of the regulation of origin efficiency is clear. In fission yeast, origin firing is stochastic, leading us to hypothesize that origin inefficiency and stochasticity are the result of a diffusible, rate-limiting activator. We show that the Hsk1-Dfp1 replication kinase (the fission yeast Cdc7-Dbf4 homologue) plays such a role. Increasing or decreasing Hsk1-Dfp1 levels correspondingly increases or decreases origin efficiency. Furthermore, tethering Hsk1-Dfp1 near an origin increases the efficiency of that origin, suggesting that the effective local concentration of Hsk1-Dfp1 regulates origin firing. Using photobleaching, we show that Hsk1-Dfp1 is freely diffusible in the nucleus. These results support a model in which the accessibility of replication origins to Hsk1-Dfp1 regulates origin efficiency and provides a potential mechanistic link between chromatin structure and replication timing. By manipulating Hsk1-Dfp1 levels, we show that increasing or decreasing origin firing rates leads to an increase in genomic instability, demonstrating the biological importance of appropriate origin efficiency.
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McConnell, Kristopher H., Philipp Müller, and Catherine A. Fox. "Tolerance of Sir1p/Origin Recognition Complex-Dependent Silencing for Enhanced Origin Firing at HMRa." Molecular and Cellular Biology 26, no. 5 (March 1, 2006): 1955–66. http://dx.doi.org/10.1128/mcb.26.5.1955-1966.2006.
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ABSTRACT The HMR-E silencer is a DNA element that directs the formation of silent chromatin at the HMR a locus in Saccharomyces cerevisiae. Sir1p is one of four Sir proteins required for silent chromatin formation at HMR a. Sir1p functions by binding the origin recognition complex (ORC), which binds to HMR-E, and recruiting the other Sir proteins (Sir2p to -4p). ORCs also bind to hundreds of nonsilencer positions distributed throughout the genome, marking them as replication origins, the sites for replication initiation. HMR-E also acts as a replication origin, but compared to many origins in the genome, it fires extremely inefficiently and late during S phase. One postulate to explain this observation is that ORC's role in origin firing is incompatible with its role in binding Sir1p and/or the formation of silent chromatin. Here we examined a mutant HMR-E silencer and fusions between robust replication origins and HMR-E for HMR a silencing, origin firing, and replication timing. Origin firing within HMR a and from the HMR-E silencer itself could be significantly enhanced, and the timing of HMR a replication during an otherwise normal S phase advanced, without a substantial reduction in SIR1-dependent silencing. However, although the robust origin/silencer fusions silenced HMR a quite well, they were measurably less effective than a comparable silencer containing HMR-E's native ORC binding site.
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Balter, M. "ORIGINS: On the Origin of Art and Symbolism." Science 323, no. 5915 (February 6, 2009): 709–11. http://dx.doi.org/10.1126/science.323.5915.709.
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Ramelli, Ilaria L. E. "Origen, Bardaiṣan, and the Origin of Universal Salvation." Harvard Theological Review 102, no. 2 (April 2009): 135–68. http://dx.doi.org/10.1017/s0017816009000728.
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Is Origen of Alexandria the inventor of the eschatological doctrine of apokatastasis— of the eventual return of all creatures to the Good, that is, God, and thus universal salvation? Certainly, he is one of its chief supporters in all of history, and he is, as far as we know, the first to have maintained it in a complete and coherent way, so that all of his philosophy of history, protology, and anthropology is oriented toward this telos.1 There are, however, significant antecedents to his mature and articulate theorization, at least some of which he surely knew very well, and there is even a possible parallel. For this conception did not appear ex nihilo, but in a cultural context rich in suggestions and premises, and in a philosophical framework of lively discussions concerning fate, free will, theodicy, and the eternal destiny of rational creatures.
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Gerhardt, Jeannine, Samira Jafar, Mark-Peter Spindler, Elisabeth Ott, and Aloys Schepers. "Identification of New Human Origins of DNA Replication by an Origin-Trapping Assay." Molecular and Cellular Biology 26, no. 20 (September 5, 2006): 7731–46. http://dx.doi.org/10.1128/mcb.01392-06.
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ABSTRACT Metazoan genomes contain thousands of replication origins, but only a limited number have been characterized so far. We developed a two-step origin-trapping assay in which human chromatin fragments associated with origin recognition complex (ORC) in vivo were first enriched by chromatin immunoprecipitation. In a second step, these fragments were screened for transient replication competence in a plasmid-based assay utilizing the Epstein-Barr virus latent origin oriP. oriP contains two elements, an origin (dyad symmetry element [DS]) and the family of repeats, that when associated with the viral protein EBNA1 facilitate extrachromosomal stability. Insertion of the ORC-binding human DNA fragments in oriP plasmids in place of DS enabled us to screen functionally for their abilities to restore replication. Using the origin-trapping assay, we isolated and characterized five previously unknown human origins. The assay was validated with nascent strand abundance assays that confirm these origins as active initiation sites in their native chromosomal contexts. Furthermore, ORC and MCM2-7 components localized at these origins during G1 phase of the cell cycle but were not detected during mitosis. This finding extends the current understanding of origin-ORC dynamics by suggesting that replication origins must be reestablished during the early stages of each cell division cycle and that ORC itself participates in this process.
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MANOLACHE, Madalina. "Ideology of Origin Effect – a Conversion of the Country of Origin Effect." Logos Universality Mentality Education Novelty. Section: SOCIAL SCIENCES 04, no. 01 (June 30, 2015): 15–21. http://dx.doi.org/10.18662/lumenss.2015.0401.01.
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Saito, Natsu. "Origin Stories: Critical Race Theory Encounters the War on Terror." Michigan Journal of Race & Law, no. 27.1 (2021): 107. http://dx.doi.org/10.36643/mjrl.27.1.origin.
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Stories matter. They matter to those intent on maintaining structures of power and privilege, and to those being crushed by those structures. In the United States, the space to tell, and to hear, our stories has been expanding. This means that the histories and lived realities of those who have been excluded, particularly people of color, are seeping into mainstream discourse, into the books our children read, the movies and television shows they watch, and the many websites comprising social media. Critical race theory has played a role in this expansion. It insists that we recognize the legitimacy of the stories of those deemed “Other” because they have been erased or distorted beyond recognition in the dominant narrative. 3 Critical race theory has helped ensure that the legacies of genocide and broken treaties, of the cruelties imposed upon enslaved persons, of the forced inclusion and exclusion of those regarded simply as disposable labor, have worked their way into the realm of what can be talked about. Critical race scholars have exposed immigration injustices and called out xenophobia and Islamophobia. All this discomfits those who benefit, or believe they benefit, from the status quo.
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Zou, Lee, and Bruce Stillman. "Assembly of a Complex Containing Cdc45p, Replication Protein A, and Mcm2p at Replication Origins Controlled by S-Phase Cyclin-Dependent Kinases and Cdc7p-Dbf4p Kinase." Molecular and Cellular Biology 20, no. 9 (May 1, 2000): 3086–96. http://dx.doi.org/10.1128/mcb.20.9.3086-3096.2000.
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ABSTRACT In Saccharomyces cerevisiae, replication origins are activated with characteristic timing during S phase. S-phase cyclin-dependent kinases (S-CDKs) and Cdc7p-Dbf4p kinase are required for origin activation throughout S phase. The activation of S-CDKs leads to association of Cdc45p with chromatin, raising the possibility that Cdc45p defines the assembly of a new complex at each origin. Here we show that both Cdc45p and replication protein A (RPA) bind to Mcm2p at the G1-S transition in an S-CDK-dependent manner. During S phase, Cdc45p associates with different replication origins at specific times. The origin associations of Cdc45p and RPA are mutually dependent, and both S-CDKs and Cdc7p-Dbf4p are required for efficient binding of Cdc45p to origins. These findings suggest that S-CDKs and Cdc7p-Dbf4p promote loading of Cdc45p and RPA onto a preformed prereplication complex at each origin with preprogrammed timing. TheARS1 association of Mcm2p, but not that of the origin recognition complex, is diminished by disruption of the B2 element ofARS1, a potential origin DNA-unwinding element. Cdc45p is required for recruiting DNA polymerase α onto chromatin, and it associates with Mcm2p, RPA, and DNA polymerase ɛ only during S phase. These results suggest that the complex containing Cdc45p, RPA, and MCMs is involved in origin unwinding and assembly of replication forks at each origin.
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Mori, Saori, and Katsuhiko Shirahige. "Perturbation of the Activity of Replication Origin by Meiosis-specific Transcription." Journal of Biological Chemistry 282, no. 7 (December 14, 2006): 4447–52. http://dx.doi.org/10.1074/jbc.m609671200.
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We have determined the activity of all ARSs on the Saccharomyces cerevisiae chromosome VI as chromosomal replication origins in premeiotic S-phase by neutral/neutral two-dimensional gel electrophoresis. The comparison of origin activity of each origin in mitotic and premeiotic S-phase showed that one of the most efficient origins in mitotic S-phase, ARS605, was completely inhibited in premeiotic S-phase. ARS605 is located within the open reading frame of MSH4 gene that is transcribed specifically during an early stage of meiosis. Systematic analysis of relationships between MSH4 transcription and ARS605 origin activity revealed that transcription of MSH4 inhibited the ARS605 origin activity by removing origin recognition complex from ARS605. Deletion of UME6, a transcription factor responsible for repressing MSH4 during mitotic S-phase, resulted in inactivation of ARS605 in mitosis. Our finding is the first demonstration that the transcriptional regulation on the replication origin activity is related to changes in cell physiology. These results may provide insights into changes in replication origin activity in embryonic cell cycle during early developmental stages.
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Campbell, Caitlin J., Matthew C. Fitzpatrick, Hannah B. Vander Zanden, and David M. Nelson. "Advancing interpretation of stable isotope assignment maps: comparing and summarizing origins of known-provenance migratory bats." Animal Migration 7, no. 1 (June 2, 2020): 27–41. http://dx.doi.org/10.1515/ami-2020-0004.
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AbstractProbability-of-origin maps deduced from stable isotope data are important for inferring broad-scale patterns of animal migration, but few resources and tools for interpreting and validating these maps exist. For example, quantitative tools for comparing multiple probability-of-origin maps do not exist, and many existing approaches for geographic assignment of individuals have not been validated or compared with respect to precision and accuracy. To address these challenges, we created and analyzed probability-of-origin maps using stable hydrogen isotope values from known-origin individuals of three species of migratory bat. We used a metric of spatial overlap to group individuals by areas of origin without a priori knowledge of such regions. The metric of spatial similarity allowed for quantitative comparison of geographic origins and grouping of individuals with similar origins. We then compared four approaches for inferring origins (cumulative-sum, odds-ratio, quantile-only, and quantile-simulation) across a range of thresholds and probable minimum distance traveled. The accuracy of geographic origins and minimum distance traveled varied across species at most threshold values for most approaches. The cumulative-sum and quantile-simulation approaches had generally higher precision at a given level of accuracy than the odds-ratio and quantile-only approaches, and many threshold values were associated with a relatively high degree (> 300 km) of variation in minimum distance traveled. Overall, these results reinforce the importance of validating assignment techniques with known-origin individuals when possible. We present the tools discussed as part of an R package, ‘isocat’ (“Isotope Origin Clustering and Assignment Tools”).
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Lowe, Janice. "Origin." Callaloo 20, no. 3 (1997): 522–23. http://dx.doi.org/10.1353/cal.1998.0078.
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Ikeda, Cathy Kanoelani. "Origin." Meridians 1, no. 1 (September 1, 2000): 112–13. http://dx.doi.org/10.1215/15366936-1.1.112.
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Seals, Ryan. "On the Origin of Origin Stories." American Scientist 104, no. 3 (2016): 184. http://dx.doi.org/10.1511/2016.120.184.
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STEVENSON, D. J. "Lunar Origin: Origin of the Moon." Science 234, no. 4779 (November 21, 1986): 1016–17. http://dx.doi.org/10.1126/science.234.4779.1016-a.
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Zhu, J., C. S. Newlon, and J. A. Huberman. "Localization of a DNA replication origin and termination zone on chromosome III of Saccharomyces cerevisiae." Molecular and Cellular Biology 12, no. 10 (October 1992): 4733–41. http://dx.doi.org/10.1128/mcb.12.10.4733-4741.1992.
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Two-dimensional gel electrophoretic replicon mapping techniques were used to identify all functional DNA replication origins and termini in a 26.5-kbp stretch in the left arm of yeast chromosome III. Only one origin was detected; it coincided with an ARS element (ARS306), as have all previously mapped yeast origins. A replication termination region was identified in a 4.3-kbp stretch at the telomere-proximal end of the investigated region, between the origin identified in this paper and the neighboring, previously mapped, ARS305-associated origin (previously called the A6C origin). Termination does not occur at a specific site; instead, it appears to be the consequence of replication forks converging in a stretch of DNA of at least 4.3 kbp.
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Zhu, J., C. S. Newlon, and J. A. Huberman. "Localization of a DNA replication origin and termination zone on chromosome III of Saccharomyces cerevisiae." Molecular and Cellular Biology 12, no. 10 (October 1992): 4733–41. http://dx.doi.org/10.1128/mcb.12.10.4733.
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Two-dimensional gel electrophoretic replicon mapping techniques were used to identify all functional DNA replication origins and termini in a 26.5-kbp stretch in the left arm of yeast chromosome III. Only one origin was detected; it coincided with an ARS element (ARS306), as have all previously mapped yeast origins. A replication termination region was identified in a 4.3-kbp stretch at the telomere-proximal end of the investigated region, between the origin identified in this paper and the neighboring, previously mapped, ARS305-associated origin (previously called the A6C origin). Termination does not occur at a specific site; instead, it appears to be the consequence of replication forks converging in a stretch of DNA of at least 4.3 kbp.
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Wang, K., and B. D. E. Chatterton. "Microspherules in Devonian sediments: origins, geological significance, and contamination problems." Canadian Journal of Earth Sciences 30, no. 8 (August 1, 1993): 1660–67. http://dx.doi.org/10.1139/e93-144.
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We have studied various microspherules (<0.5 mm across) that were found in Devonian sediments from Canada and China during our micropaleontological studies (e.g., conodont picking). These spherules are similar in appearance, but they are quite different in origin. A combined scanning electron microscope, energy dispersive X-ray, X-ray microdiffraction, and electron microprobe analysis enables us to determine their probable origins: phosphatic conodont pearls of biological origin; silicate glass microtektites of terrestrial meteorite-impact origin; and black, magnetic iron spherules of probable extraterrestrial origin. We also observed some contaminant spherules (glue spatters and steel slag) of artificial origins. Studies of natural spherules in sediments can provide important geological information that may be otherwise undetectable.
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Boos, Dominik, and Pedro Ferreira. "Origin Firing Regulations to Control Genome Replication Timing." Genes 10, no. 3 (March 6, 2019): 199. http://dx.doi.org/10.3390/genes10030199.
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Complete genome duplication is essential for genetic homeostasis over successive cell generations. Higher eukaryotes possess a complex genome replication program that involves replicating the genome in units of individual chromatin domains with a reproducible order or timing. Two types of replication origin firing regulations ensure complete and well-timed domain-wise genome replication: (1) the timing of origin firing within a domain must be determined and (2) enough origins must fire with appropriate positioning in a short time window to avoid inter-origin gaps too large to be fully copied. Fundamental principles of eukaryotic origin firing are known. We here discuss advances in understanding the regulation of origin firing to control firing time. Work with yeasts suggests that eukaryotes utilise distinct molecular pathways to determine firing time of distinct sets of origins, depending on the specific requirements of the genomic regions to be replicated. Although the exact nature of the timing control processes varies between eukaryotes, conserved aspects exist: (1) the first step of origin firing, pre-initiation complex (pre-IC formation), is the regulated step, (2) many regulation pathways control the firing kinase Dbf4-dependent kinase, (3) Rif1 is a conserved mediator of late origin firing and (4) competition between origins for limiting firing factors contributes to firing timing. Characterization of the molecular timing control pathways will enable us to manipulate them to address the biological role of replication timing, for example, in cell differentiation and genome instability.
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Karnani, Neerja, Christopher M. Taylor, Ankit Malhotra, and Anindya Dutta. "Genomic Study of Replication Initiation in Human Chromosomes Reveals the Influence of Transcription Regulation and Chromatin Structure on Origin Selection." Molecular Biology of the Cell 21, no. 3 (February 2010): 393–404. http://dx.doi.org/10.1091/mbc.e09-08-0707.
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DNA replication in metazoans initiates from multiple chromosomal loci called origins. Currently, there are two methods to purify origin-centered nascent strands: lambda exonuclease digestion and anti-bromodeoxyuridine immunoprecipitation. Because both methods have unique strengths and limitations, we purified nascent strands by both methods, hybridized them independently to tiling arrays (1% genome) and compared the data to have an accurate view of genome-wide origin distribution. By this criterion, we identified 150 new origins that were reproducible across the methods. Examination of a subset of these origins by chromatin immunoprecipitation against origin recognition complex (ORC) subunits 2 and 3 showed 93% of initiation peaks to localize at/within 1 kb of ORC binding sites. Correlation of origins with functional elements of the genome revealed origin activity to be significantly enriched around transcription start sites (TSSs). Consistent with proximity to TSSs, we found a third of initiation events to occur at or near the RNA polymerase II binding sites. Interestingly, ∼50% of the early origin activity was localized within 5 kb of transcription regulatory factor binding region clusters. The chromatin signatures around the origins were enriched in H3K4-(di- and tri)-methylation and H3 acetylation modifications on histones. Affinity of origins for open chromatin was also reiterated by their proximity to DNAse I-hypersensitive sites. Replication initiation peaks were AT rich, and >50% of the origins mapped to evolutionarily conserved regions of the genome. In summary, these findings indicate that replication initiation is influenced by transcription initiation and regulation as well as chromatin structure.
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Bora, Rishabh, and Neharika Malhotra Bora. "Fetal Origin of Adult Disease." Donald School Journal of Ultrasound in Obstetrics and Gynecology 8, no. 2 (2014): 164–77. http://dx.doi.org/10.5005/jp-journals-10009-1352.
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ABSTRACT Fetal origins of adult disease, a concept first popularized by Dr David Barker, has subsequently led to many studies which have provided the evidence that certain diseases do have links pointing to fetal origins—adverse influences early in development, and particularly during intrauterine life, can result in permanent changes in physiology and metabolism, which result in increased disease risk in adulthood. Links that are well-established are—reduced birth weight and increased risk of coronary heart disease, hypertension and stroke in adulthood. The concept of a fetal origin of adult disease have been extended well-beyond coronary heart disease and being a risk factor for coronary heart disease, and now includes investigations of the development of the central nervous system, early origins of adult mental health and cognitive function. By understanding fetal origin of adult disease, health care professionals and policy makers will make this issue a high health care priority and implement preventive measures and treatment for those at higher risk for chronic diseases. How to cite this article Malhotra N, Malhotra J, Bora NM, Bora R, Malhotra K. Fetal Origin of Adult Disease. Donald School J Ultrasound Obstet Gynecol 2014;8(2):164-177.
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Rhind, Nicholas. "f = m*a: A Framework for Investigating the Regulation of Replication Timing." Genes 13, no. 2 (January 28, 2022): 249. http://dx.doi.org/10.3390/genes13020249.
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Stochastic models of replication timing posit that origin firing timing is regulated by origin firing probability, with early-firing origins having a high probability of firing and late-firing origins having a lower probability. However, they offer no insight into why one origin should have a higher firing probability than another. Here, a simple framework is suggested for how to approach the question by noting that the firing probability (f) must be the product of the stoichiometry of the MCM replicative helicase loaded at the origin (m) and the probability with which that MCM is activated (a). This framework emphasizes that mechanistic understanding of replication timing must focus on MCM loading and activation and can be simplified to the equation f = m*a.
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Dumitru, Cătălin Constantin, Sorin Hostiuc, Alexandra Diana Vrapciu, and Mugurel Constantin Rusu. "Vertical Levels of the Occipital Artery Origin." Medicina 59, no. 2 (February 8, 2023): 317. http://dx.doi.org/10.3390/medicina59020317.
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Background and Objectives. The occipital artery (OA) is a posterior branch of the external carotid artery (ECA). The origin of the OA is commonly referred to a single landmark. We hypothesized that the origin of the OA could be variable as referred to the hyoid bone and the gonial angle. We thus aimed at patterning the vertical topographic possibilities of the OA origin. Materials and Methods. One hundred archived computed tomography angiograms were randomly selected, inclusion and exclusion criteria were applied, and 90 files were kept (53 males, 37 females). The cases were documented bilaterally for different levels of origin of the OA origin: type 1—infrahyoid; type 2—hyoid; 3—infragonial; 4—gonial; 5—supragonial; 6—origin from the internal carotid artery (ICA). Results. The incidence of unilateral types in the 180 OAs was: type 1—1.11%, type 2—5.56%, type 3—40.56%, type 4—28.33%, type 5—23.33% and type 6, ICA origin of the OA—1.11%. There was found a significant association between the location of the left and right origins of the OAs (Pearson Chi2 = 59.18, p < 0.001), which suggests the presence of a strong symmetry of the origins. Bilateral symmetry of the vertical types of the OA origin was observed in 56.67% of cases; in 43.33% there was bilateral asymmetry. Conclusions. The ICA origin of the OA is an extremely rare variant. For surgical planning or prior to endovascular approaches the topography of the OA origin should be carefully documented, as it may be located from an infrahyoid to a supragonial level.
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Lebofsky, Ronald, Roland Heilig, Max Sonnleitner, Jean Weissenbach, and Aaron Bensimon. "DNA Replication Origin Interference Increases the Spacing between Initiation Events in Human Cells." Molecular Biology of the Cell 17, no. 12 (December 2006): 5337–45. http://dx.doi.org/10.1091/mbc.e06-04-0298.
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Mammalian DNA replication origins localize to sites that range from base pairs to tens of kilobases. A regular distribution of initiations in individual cell cycles suggests that only a limited number of these numerous potential start sites are converted into activated origins. Origin interference can silence redundant origins; however, it is currently unknown whether interference participates in spacing functional human initiation events. By using a novel hybridization strategy, genomic Morse code, on single combed DNA molecules from primary keratinocytes, we report the initiation sites present on 1.5 Mb of human chromosome 14q11.2. We confirm that initiation zones are widespread in human cells, map to intergenic regions, and contain sequence motifs found at other mammalian initiation zones. Origins used per cell cycle are less abundant than the potential sites of initiation, and their limited use increases the spacing between initiation events. Between-zone interference decreases in proportion to the distance from the active origin, whereas within-zone interference is 100% efficient. These results identify a hierarchical organization of origin activity in human cells. Functional origins govern the probability that nearby origins will fire in the context of multiple potential start sites of DNA replication, and this is mediated by origin interference.
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Paixão, Sónia, Ivan N. Colaluca, Matthieu Cubells, Fiorenzo A. Peverali, Annarita Destro, Sara Giadrossi, Mauro Giacca, Arturo Falaschi, Silvano Riva, and Giuseppe Biamonti. "Modular Structure of the Human Lamin B2 Replicator." Molecular and Cellular Biology 24, no. 7 (April 1, 2004): 2958–67. http://dx.doi.org/10.1128/mcb.24.7.2958-2967.2004.
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ABSTRACT The cis-acting elements necessary for the activity of DNA replication origins in metazoan cells are still poorly understood. Here we report a thorough characterization of the DNA sequence requirements of the origin associated with the human lamin B2 gene. A 1.2-kb DNA segment, comprising the start site of DNA replication and located within a large protein-bound region, as well as a CpG island, displays origin activity when moved to different ectopic positions. Genomic footprinting analysis of both the endogenous and the ectopic origins indicates that the large protein complex is assembled in both cases around the replication start site. Replacement of this footprinted region with an unrelated sequence, maintaining the CpG island intact, abolishes origin activity and the interaction with hORC2, a subunit of the origin recognition complex. Conversely, the replacement of 17 bp within the protected region reduces the extension of the protection without affecting the interaction with hORC2. This substitution does not abolish the origin activity but makes it more sensitive to the integration site. Finally, the nearby CpG island positively affects the efficiency of initiation. This analysis reveals the modular structure of the lamin B2 origin and supports the idea that sequence elements close to the replication start site play an important role in origin activation.
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Bai, Xiuyun, Hengye Chen, Wanjun Long, Wei Lan, Siyu Wang, Guanghua Lei, Yuting Guan, Jian Yang, and Haiyan Fu. "Accurate Traceability of Stable C, H, O, N Isotope Ratios and Multi-Element Analysis Combined with Chemometrics for Chrysanthemi Flos ‘Hangbaiju’ from Different Origins." Chemosensors 10, no. 12 (December 12, 2022): 529. http://dx.doi.org/10.3390/chemosensors10120529.
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Chrysanthemi Flos ‘Hangbaiju’ (HBJ) is a common Chinese medicinal material with the same origin as the medicinal and edible cognate plant in China, whose quality is seriously affected by the place of origin. In this study, four stable isotope ratios (δ15N, δ2H, δ13C, and δ18O) and 44 elements were detected and analyzed in 191 HBJ flower samples from six locations in China to trace the origin of HBJ. An ANOVA analysis of δ15N, δ2H, δ13C, and δ18O values, as well as milti-elements, showed that there were significant differences among the six places of origin. Partial least squares discriminant analysis (PLSDA) and one-class partial least squares discriminant analysis (OPLS-DA) models were established to trace the origin of HBJ from these six locations. The results showed that the classification effect of the PLSDA model is poor; however, the established OPLS-DA model can distinguish between products of national geographic origin (Tongxiang City, Zhejiang Province, China) and samples from other origins, among which Ni, Mo, δ13C, Cu, and Ce elements (VIP > 1) contribute the most to this classification. Therefore, this study provides a new method for tracing the origins of HBJ, which is of great significance for the protection of origin labeling of products.
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Coulibaly, Yacouba Noel, and Gerard Zombre. "Evaluating the effects of water stress and irrigation on three cashew origins at juvenile stage for adaptation of agroforestry systems to drought under climate change in Burkina Faso (West Africa)." International Journal of Biological and Chemical Sciences 18, no. 3 (September 4, 2024): 963–72. http://dx.doi.org/10.4314/ijbcs.v18i3.19.
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The Drought threatens cashew-based agroforestry systems productivity in Burkina Faso. The objective of this research was to study the effects of water stress and irrigation on 03 cashew origins for recommendations to maintain and/or improve cashew based agroforestry systems productivity. The experiment was conducted in a semi-controlled environment using randomised complete blocks, studying the factors water regime and origin at 03 levels. The number of replication was 4 and the experimental unit was 4 pots. Total dry biomass, height and survival percentage were measured. The effect of water regime, origin and their interaction were highly significant (P<0,0001) on total dry biomass and height. The effect of water regime was highly significant (P<0,0001) while the effect of origin and the interaction were very significant (P=0,004) on survival percentage. Diakadougou origin performed better and the parameters measured were reduced under water stress and increased under irrigation. Diakadougou origin was the most drought tolerant and Ouessa origin the most demanding in water. Irrigation and use of drought tolerant origin Diakadougou could contribute in adaptation to drought of cashew based agroforestry systems. Further research to study drought and irrigation effects on physiological parameters of the cashew origins studied is required.
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Borovsky, Joseph E. "The superdense plasma sheet: Plasmaspheric origin, solar wind origin, or ionospheric origin?" Journal of Geophysical Research 102, A10 (1997): 22089–106. http://dx.doi.org/10.1029/97ja02469.
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Borovsky, Joseph E., Michelle F. Thomsen, and David J. McComas. "The superdense plasma sheet: Plasmaspheric origin, solar wind origin, or ionospheric origin?" Journal of Geophysical Research: Space Physics 102, A10 (October 1, 1997): 22089–97. http://dx.doi.org/10.1029/96ja02469.
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Collins, I., and C. S. Newlon. "Chromosomal DNA replication initiates at the same origins in meiosis and mitosis." Molecular and Cellular Biology 14, no. 5 (May 1994): 3524–34. http://dx.doi.org/10.1128/mcb.14.5.3524-3534.1994.
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Autonomously replicating sequence (ARS) elements are identified by their ability to promote high-frequency transformation and extrachromosomal replication of plasmids in the yeast Saccharomyces cerevisiae. Six of the 14 ARS elements present in a 200-kb region of Saccharomyces cerevisiae chromosome III are mitotic chromosomal replication origins. The unexpected observation that eight ARS elements do not function at detectable levels as chromosomal replication origins during mitotic growth suggested that these ARS elements may function as chromosomal origins during premeiotic S phase. Two-dimensional agarose gel electrophoresis was used to map premeiotic replication origins in a 100-kb segment of chromosome III between HML and CEN3. The pattern of origin usage in premeiotic S phase was identical to that in mitotic S phase, with the possible exception of ARS308, which is an inefficient mitotic origin associated with CEN3. CEN3 was found to replicate during premeiotic S phase, demonstrating that the failure of sister chromatids to disjoin during the meiosis I division is not due to unreplicated centromeres. No origins were found in the DNA fragments without ARS function. Thus, in both mitosis and meiosis, chromosomal replication origins are coincident with ARS elements but not all ARS elements have chromosomal origin function. The efficiency of origin use and the patterns of replication termination are similar in meiosis and in mitosis. DNA replication termination occurs over a broad distance between active origins.
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Collins, I., and C. S. Newlon. "Chromosomal DNA replication initiates at the same origins in meiosis and mitosis." Molecular and Cellular Biology 14, no. 5 (May 1994): 3524–34. http://dx.doi.org/10.1128/mcb.14.5.3524.
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Autonomously replicating sequence (ARS) elements are identified by their ability to promote high-frequency transformation and extrachromosomal replication of plasmids in the yeast Saccharomyces cerevisiae. Six of the 14 ARS elements present in a 200-kb region of Saccharomyces cerevisiae chromosome III are mitotic chromosomal replication origins. The unexpected observation that eight ARS elements do not function at detectable levels as chromosomal replication origins during mitotic growth suggested that these ARS elements may function as chromosomal origins during premeiotic S phase. Two-dimensional agarose gel electrophoresis was used to map premeiotic replication origins in a 100-kb segment of chromosome III between HML and CEN3. The pattern of origin usage in premeiotic S phase was identical to that in mitotic S phase, with the possible exception of ARS308, which is an inefficient mitotic origin associated with CEN3. CEN3 was found to replicate during premeiotic S phase, demonstrating that the failure of sister chromatids to disjoin during the meiosis I division is not due to unreplicated centromeres. No origins were found in the DNA fragments without ARS function. Thus, in both mitosis and meiosis, chromosomal replication origins are coincident with ARS elements but not all ARS elements have chromosomal origin function. The efficiency of origin use and the patterns of replication termination are similar in meiosis and in mitosis. DNA replication termination occurs over a broad distance between active origins.
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Dershowitz, A., and C. S. Newlon. "The effect on chromosome stability of deleting replication origins." Molecular and Cellular Biology 13, no. 1 (January 1993): 391–98. http://dx.doi.org/10.1128/mcb.13.1.391-398.1993.
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The observed spacing between chromosomal DNA replication origins in Saccharomyces cerevisiae is at least four times shorter than should be necessary to ensure complete replication of chromosomal DNA during the S phase. To test whether all replication origins are required for normal chromosome stability, the loss rates of derivatives of chromosome III from which one or more origins had been deleted were measured. In the case of a 61-kb circular derivative of the chromosome that has two highly active origins and one origin that initiates only 10 to 20% of the time, deletion of either highly active origin increased its rate of loss two- to fourfold. Deletion of both highly active origins caused the ring chromosome to be lost in approximately 20% of cell divisions. This very high rate of loss demonstrates that there are no efficient cryptic origins on the ring chromosome that are capable of ensuring its replication in the absence of the origins that are normally used. Deletion of the same two origins from the full-length chromosome III, which contains more than six replication origins, had no effect on its rate of loss. These results suggest that the increase in the rate of loss of the small circular chromosome from which a single highly active origin was deleted was caused by the failure of the remaining highly active origin to initiate replication in a small fraction (approximately 0.003) of cell cycles.
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Dershowitz, A., and C. S. Newlon. "The effect on chromosome stability of deleting replication origins." Molecular and Cellular Biology 13, no. 1 (January 1993): 391–98. http://dx.doi.org/10.1128/mcb.13.1.391.
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The observed spacing between chromosomal DNA replication origins in Saccharomyces cerevisiae is at least four times shorter than should be necessary to ensure complete replication of chromosomal DNA during the S phase. To test whether all replication origins are required for normal chromosome stability, the loss rates of derivatives of chromosome III from which one or more origins had been deleted were measured. In the case of a 61-kb circular derivative of the chromosome that has two highly active origins and one origin that initiates only 10 to 20% of the time, deletion of either highly active origin increased its rate of loss two- to fourfold. Deletion of both highly active origins caused the ring chromosome to be lost in approximately 20% of cell divisions. This very high rate of loss demonstrates that there are no efficient cryptic origins on the ring chromosome that are capable of ensuring its replication in the absence of the origins that are normally used. Deletion of the same two origins from the full-length chromosome III, which contains more than six replication origins, had no effect on its rate of loss. These results suggest that the increase in the rate of loss of the small circular chromosome from which a single highly active origin was deleted was caused by the failure of the remaining highly active origin to initiate replication in a small fraction (approximately 0.003) of cell cycles.
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Zhang, Ren, and Chun-Ting Zhang. "Identification of replication origins in archaeal genomes based on theZ-curve method." Archaea 1, no. 5 (2005): 335–46. http://dx.doi.org/10.1155/2005/509646.
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TheZ-curve is a three-dimensional curve that constitutes a unique representation of a DNA sequence, i.e., both theZ-curve and the given DNA sequence can be uniquely reconstructed from the other. We employedZ-curve analysis to identify one replication origin in theMethanocaldococcus jannaschiigenome, two replication origins in theHalobacteriumspecies NRC-1 genome and one replication origin in theMethanosarcina mazeigenome. One of the predicted replication origins ofHalobacteriumspecies NRC-1 is the same as a replication origin later identified by in vivo experiments. TheZ-curve analysis of theSulfolobus solfataricusP2 genome suggested the existence of three replication origins, which is also consistent with later experimental results. This review aims to summarize applications of theZ-curve in identifying replication origins of archaeal genomes, and to provide clues about the locations of as yet unidentified replication origins of theAeropyrum pernixK1,Methanococcus maripaludisS2,Picrophilus torridusDSM 9790 andPyrobaculum aerophilumstr. IM2 genomes.
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Su, Yue, and Mingxing Yang. "Combining Rare Earth Element Analysis and Chemometric Method to Determine the Geographical Origin of Nephrite." Minerals 12, no. 11 (October 31, 2022): 1399. http://dx.doi.org/10.3390/min12111399.
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Nephrite is a high-valued gem material, whose geographical origin determination is a topic of interest to both consumers and producers since the geographic origin determines its price and reputation. In the present study, we suggest a two-step method for discriminating geographical origins of nephrite based on the rare earth element (REE) contents combined with chemometrics. In the first step, the REE contents of nephrite samples were determined by laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS), combined with previously reported data—the chondrite-normalized REE distribution pattern; the REE parameters of nephrite samples from six origins, namely Xinjiang, Qinghai, Russia, Guangxi, Guizhou, and Liaoning were then compared. In the second step, origin discriminant models were established by linear discriminant analysis (LDA), and the accuracy of the model was evaluated by leave-one-out cross-validation (LOOCV). The results showed that the REE contents were significantly different among the six nephrite origins with regional characteristics, which makes it possible to trace the origin. Using chondrite-normalized REE distribution patterns, the six nephrite origins can be divided into three separate groups: Xinjiang−Qinghai−Russia, Luodian−Dahua, and Xiuyan. Xiuyan nephrite can be directly distinguished from the other origins due to its unique REE distribution pattern. In the second step, the LDA discrimination models were performed on the remaining two groups. For the Luodian−Dahua group, the accuracy of the original classification and LOOCV were 97.9% and 85.4%, which indicated REE combined with LDA could effectively identify Luodian nephrite and Dahua nephrite. For the Xinjiang−Qinghai−Russia group, the accuracy of the original classification and LOOCV was 74.1% and 63.9%, respectively. Overall, this work proves that a combination of REE analysis and chemometrics has a certain feasibility and broad application prospects for geographical origin, and the same methodology can be applied to study the origin of other gem materials.
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Cheng, Tao, Sen Guo, Zhenggao Pan, Shuxiang Fan, Shucun Ju, Zhenghua Xin, Xin-Gen Zhou, Fei Jiang, and Dongyan Zhang. "Near-Infrared Model and Its Robustness as Affected by Fruit Origin for ‘Dangshan’ Pear Soluble Solids Content and pH Measurement." Agriculture 12, no. 10 (October 5, 2022): 1618. http://dx.doi.org/10.3390/agriculture12101618.
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Soluble solid content (SSC) and acidity (pH) are two important factors indicating the fruit quality of pears and can be measured by near-infrared spectroscopy (NIRS). However, the robustness of these measurements as affected by different origins of pears remains largely unknown. In this study, we developed an NIRS method to measure ‘Dangshan’ pear (Pyrus spp.) SSC and pH and evaluated the robustness of this non-destructive detection method by examining the effects of pears from three different origins in 2019 and 2020. First, the Kennard–Stone method was used to divide the calibration set of the 2020 pear samples from different orchards. The partial least squares (PLS) model was used to establish the local origin and hybrid origin models to predict the pears’ SSC and pH. Second, a combination of competitive adaptive reweighted sampling (CARS), successive projections algorithm (SPA), and uninformative variable elimination (UVE) was implemented to construct spectral prediction models based on effective variables for assessing the pears’ SSC and pH from local and hybrid origins. The results showed that the local origin detection model produced large errors in predicting the SSC and pH of pears from different origins, and the model, established based on the pear samples of three origins, performed better than the local origin and other hybrid origin models. Finally, the model could be effectively simplified using 70 and 52 characteristic variables selected by the CARS method. Pear samples harvested from three different orchards in 2019 were used as an independent set to verify the validity of the selected characteristic variables. The results showed that the predicted R2p for the SSC and pH measurements of pears of three different origins were more than 0.9 and 0.85, respectively. This finding indicates that the difference in the origin of pears has an important influence on the quantitative inversion of pear SSC and pH measurements, and the combination of the hybrid origin model constructed based on the characteristic variables can improve the prediction accuracy. These findings provide an important theoretical basis for the development of rapid detection devices for the measurements of pears’ SSC and pH.
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Kurniawan, I. Komang Gede, and I. Made Wirya Darma. "The Legal Protection for Folk Songs from Unknown Origin: Orientation and Formulation in the Perspective of Legal Cybernetics." SASI 29, no. 4 (October 30, 2023): 755. http://dx.doi.org/10.47268/sasi.v29i4.1722.
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Introduction: The existence of the phenomenon of regional songs whose regional origins are unknown has led to legal problems in the form of a legal vacuum regarding legal protection. Existing laws and regulations are still missing in providing arrangements regarding regional songs whose regional origin is unknown.Purposes of the Research: This study aims to analyze and at the same time seek legal protection through special arrangements regarding regional songs whose regional origins are unclear.Methods of the Research: Normative legal research with a conceptual and statutory approach.Results of the Research: The orientation to provide legal protection for folk songs of unknown origin can actually be carried out by issuing specific implementing regulations that regulate and facilitate folk songs of unknown origin to obtain legal protection. Legal protection for folk songs of unknown origin in the perspective of legal cybernetics can be carried out by establishing special regulations, research and studies, as well as cultural titles and festivals for folk songs of unknown origin. This is because legal protection for folk songs of unknown origin based on a legal cybernetics perspective needs to be carried out, especially by involving the political will of the local government and local cultural figures.
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Cohen, Meryl S., René J. Herlong, and Norman H. Silverman. "Echocardiographic imaging of anomalous origin of the coronary arteries." Cardiology in the Young 20, S3 (December 2010): 26–34. http://dx.doi.org/10.1017/s104795111000106x.
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AbstractIn the past, coronary arterial anomalies have been difficult to diagnose by non-invasive methods. Identification of coronary arterial origins is now a routine part of the standard paediatric echocardiogram. Anomalous origin of a coronary artery from the pulmonary trunk is an extremely important diagnosis to make. Many echocardiographic features are not directly related to the visualisation of the coronary arterial origin. Left ventricular dilation and abnormal ventricular performance are common, along with mitral regurgitation and evidence of collateralisation of the flow from the coronary artery that has an aortic origin. In some cases, the anomalous coronary artery can be seen to arise directly from the pulmonary trunk. Congenital atresia of the main stem of the left coronary artery has a similar echocardiographic presentation, except that its aortic origin is not determined. Anomalous aortic origin of the coronary artery has important implications, as the first presenting symptom can be sudden death. With meticulous attention to the origins of the coronary arteries, echocardiographic diagnosis can also be achieved. In contrast to the anomalous origin of a coronary artery from the pulmonary trunk, ventricular performance is usually normal. Whenever there is doubt as to the definition of the origin of the coronary arteries and, indeed, when there is serious clinical concern that a coronary artery has an anomalous origin, other testing, such as cine-computed tomography, magnetic resonance imaging, or cardiac catheterisation may be indicated for confirmation or to provide greater anatomic detail.
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Zhou, Xiuwen, Beibei Xiong, Xiao Ma, Baohui Jin, Liqi Xie, Karyne M. Rogers, Hui Zhang, and Hao Wu. "Towards Verifying the Imported Soybeans of China Using Stable Isotope and Elemental Analysis Coupled with Chemometrics." Foods 12, no. 23 (November 23, 2023): 4227. http://dx.doi.org/10.3390/foods12234227.
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Verifying the geographical origin of soybeans (Glycine max [Linn.] Merr.) is a major challenge as there is little available information regarding non-parametric statistical origin approaches for Chinese domestic and imported soybeans. Commercially procured soybean samples from China (n = 33) and soybeans imported from Brazil (n = 90), the United States of America (n = 6), and Argentina (n = 27) were collected to characterize different producing origins using stable isotopes (δ2H, δ18O, δ15N, δ13C, and δ34S), non-metallic element content (% N, % C, and % S), and 23 mineral elements. Chemometric techniques such as principal component analysis (PCA), linear discriminant analysis (LDA), and BP–artificial neural network (BP-ANN) were applied to classify each origin profile. The feasibility of stable isotopes and elemental analysis combined with chemometrics as a discrimination tool to determine the geographical origin of soybeans was evaluated, and origin traceability models were developed. A PCA model indicated that origin discriminant separation was possible between the four soybean origins. Soybean mineral element content was found to be more indicative of origin than stable isotopes or non-metallic element contents. A comparison of two chemometric discriminant models, LDA and BP-ANN, showed both achieved an overall accuracy of 100% for testing and training sets when using a combined isotope and elemental approach. Our findings elucidate the importance of a combined approach in developing a reliable origin labeling method for domestic and imported soybeans in China.
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Gella, Pablo, Margarita Salas, and Mario Mencía. "Improved artificial origins for phage Φ29 terminal protein-primed replication. Insights into early replication events." Nucleic Acids Research 42, no. 15 (July 31, 2014): 9792–806. http://dx.doi.org/10.1093/nar/gku660.
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Abstract The replication machinery of bacteriophage Φ29 is a paradigm for protein-primed replication and it holds great potential for applied purposes. To better understand the early replication events and to find improved origins for DNA amplification based on the Φ29 system, we have studied the end-structure of a double-stranded DNA replication origin. We have observed that the strength of the origin is determined by a combination of factors. The strongest origin (30-fold respect to wt) has the sequence CCC at the 3′ end of the template strand, AAA at the 5′ end of the non-template strand and 6 nucleotides as optimal unpairing at the end of the origin. We also show that the presence of a correctly positioned displaced strand is important because origins with 5′ or 3′ ssDNA regions have very low activity. Most of the effect of the improved origins takes place at the passage between the terminal protein-primed and the DNA-primed modes of replication by the DNA polymerase suggesting the existence of a thermodynamic barrier at that point. We suggest that the template and non-template strands of the origin and the TP/DNA polymerase complex form series of interactions that control the critical start of terminal protein-primed replication.