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Добірка наукової літератури з теми "Bcov"

Автор: Grafiati

Опубліковано: 13 квітня 2024

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Статті в журналах з теми "Bcov"

Suzuki, Tohru, Yoshihiro Otake, Satoko Uchimoto, Ayako Hasebe, and Yusuke Goto. "Genomic Characterization and Phylogenetic Classification of Bovine Coronaviruses Through Whole Genome Sequence Analysis." Viruses 12, no. 2 (February 6, 2020): 183. http://dx.doi.org/10.3390/v12020183.

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Анотація:

Bovine coronavirus (BCoV) is zoonotically transmissible among species, since BCoV-like viruses have been detected in wild ruminants and humans. BCoV causing enteric and respiratory disease is widespread in cattle farms worldwide; however, limited information is available regarding the molecular characterization of BCoV because of its large genome size, despite its significant economic impact. This study aimed to better understand the genomic characterization and evolutionary dynamics of BCoV via comparative sequence and phylogenetic analyses through whole genome sequence analysis using 67 BCoV isolates collected throughout Japan from 2006 to 2017. On comparing the genomic sequences of the 67 BCoVs, genetic variations were detected in 5 of 10 open reading frames (ORFs) in the BCoV genome. Phylogenetic analysis using whole genomes from the 67 Japanese BCoV isolates in addition to those from 16 reference BCoV strains, revealed the existence of two major genotypes (classical and US wild ruminant genotypes). All Japanese BCoV isolates originated from the US wild ruminant genotype, and they tended to form the same clusters based on the year and farm of collection, not the disease type. Phylogenetic trees on hemagglutinin-esterase protein (HE), spike glycoprotein (S), nucleocapsid protein (N) genes and ORF1 revealed clusters similar to that on whole genome, suggesting that the evolution of BCoVs may be closely associated with variations in these genes. Furthermore, phylogenetic analysis of BCoV S genes including those of European and Asian BCoVs and human enteric coronavirus along with the Japanese BCoVs revealed that BCoVs differentiated into two major types (European and American types). Moreover, the European and American types were divided into eleven and three genotypes, respectively. Our analysis also demonstrated that BCoVs with different genotypes periodically emerged and predominantly circulated within the country. These findings provide useful information to elucidate the detailed molecular characterization of BCoVs, which have spread worldwide. Further genomic analyses of BCoV are essential to deepen the understanding of the evolution of this virus.

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Hasoksuz, Mustafa, Konstantin Alekseev, Anastasia Vlasova, Xinsheng Zhang, David Spiro, Rebecca Halpin, Shiliang Wang, Elodie Ghedin, and Linda J. Saif. "Biologic, Antigenic, and Full-Length Genomic Characterization of a Bovine-Like Coronavirus Isolated from a Giraffe." Journal of Virology 81, no. 10 (March 7, 2007): 4981–90. http://dx.doi.org/10.1128/jvi.02361-06.

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ABSTRACT Coronaviruses (CoVs) possess large RNA genomes and exist as quasispecies, which increases the possibility of adaptive mutations and interspecies transmission. Recently, CoVs were recognized as important pathogens in captive wild ruminants. This is the first report of the isolation and detailed genetic, biologic, and antigenic characterization of a bovine-like CoV from a giraffe (Giraffa camelopardalis) in a wild-animal park in the United States. CoV particles were detected by immune electron microscopy in fecal samples from three giraffes with mild-to-severe diarrhea. From one of the three giraffe samples, a CoV (GiCoV-OH3) was isolated and successfully adapted to serial passage in human rectal tumor 18 cell cultures. Hemagglutination assays, receptor-destroying enzyme activity, hemagglutination inhibition, and fluorescence focus neutralization tests revealed close biological and antigenic relationships between the GiCoV-OH3 isolate and selected respiratory and enteric bovine CoV (BCoV) strains. When orally inoculated into a BCoV-seronegative gnotobiotic calf, GiCoV-OH3 caused severe diarrhea and virus shedding within 2 to 3 days. Sequence comparisons and phylogenetic analyses were performed to assess its genetic relatedness to other CoVs. Molecular characterization confirmed that the new isolate belongs to group 2a of the mammalian CoVs and revealed closer genetic relatedness between GiCoV-OH3 and the enteric BCoVs BCoV-ENT and BCoV-DB2, whereas BCoV-Mebus was more distantly related. Detailed sequence analysis of the GiCoV-OH3 spike gene demonstrated the presence of a deletion in the variable region of the S1 subunit (from amino acid 543 to amino acid 547), which is a region associated with pathogenicity and tissue tropism for other CoVs. The point mutations identified in the structural proteins (by comparing GiCoV-OH3, BCoV-ENT, BCoV-DB2, and BCoV-Mebus) were most conserved among GiCoV-OH3, BCoV-ENT, and BCoV-DB2, whereas most of the point mutations in the nonstructural proteins were unique to GiCoV-OH3. Our results confirm the existence of a bovine-like CoV transmissible to cattle from wild ruminants, namely, giraffes, but with certain genetic properties different from those of BCoVs.

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Bidokhti, Mehdi R. M., Madeleine Tråvén, Neel K. Krishna, Muhammad Munir, Sándor Belák, Stefan Alenius, and Martí Cortey. "Evolutionary dynamics of bovine coronaviruses: natural selection pattern of the spike gene implies adaptive evolution of the strains." Journal of General Virology 94, no. 9 (September 1, 2013): 2036–49. http://dx.doi.org/10.1099/vir.0.054940-0.

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Анотація:

Coronaviruses demonstrate great potential for interspecies transmission, including zoonotic outbreaks. Although bovine coronavirus (BCoV) strains are frequently circulating in cattle farms worldwide, causing both enteric and respiratory disease, little is known about their genomic evolution. We sequenced and analysed the full-length spike (S) protein gene of 33 BCoV strains from dairy and feedlot farms collected during outbreaks that occurred from 2002 to 2010 in Sweden and Denmark. Amino acid identities were >97 % for the BCoV strains analysed in this work. These strains formed a clade together with Italian BCoV strains and were highly similar to human enteric coronavirus HECV-4408/US/94. A high similarity was observed between BCoV, canine respiratory coronavirus (CRCoV) and human coronavirus OC43 (HCoV-OC43). Molecular clock analysis of the S gene sequences estimated BCoV and CRCoV diverged from a common ancestor in 1951, while the time of divergence from a common ancestor of BCoV and HCoV-OC43 was estimated to be 1899. BCoV strains showed the lowest similarity to equine coronavirus, placing the date of divergence at the end of the eighteenth century. Two strongly positive selection sites were detected along the receptor-binding subunit of the S protein gene: spanning amino acid residues 109–131 and 495–527. By contrast, the fusion subunit was observed to be under negative selection. The selection pattern along the S glycoprotein implies adaptive evolution of BCoVs, suggesting a successful mechanism for BCoV to continuously circulate among cattle and other ruminants without disappearance.

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Prasad, Minakshi. "Jumping of Camelid Coronavirus in Bovines: A Report from Rural Area of Haryana, India." Open Access Journal of Veterinary Science & Research 4, no. 3 (2019): 1–10. http://dx.doi.org/10.23880/oajvsr-16000183.

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Анотація:

Bovine coronaviruses (BCoVs) are generally species specific, but cross species transmission has been demonstrated experimentally. Several examples have represented the infection of humans by coronavirus. Most of the coronaviruses are found in domestic as well as wild animals, and it is possible that they arose in human population though zoonotic transmission. In the present study, we evaluated presence of bovine corona virus (BCoV) in bovine fecal samples and reported the infection using RT - PCR assay. BCoV was detected using trans - membrane (M) gene specific RT - PCR with 523 bp amplicon size. A total three hundred thirteen (313) bovine fecal samples were collected for the present study. Out of 313 buffalo fecal samples, 31 buffalo were found infected with coronavirus by RT - PCR assay. The results suggest that RT - PCR is sensitive and specific method to detect BCoV, especially in subclinical cases. These results were further c onfirmed by sequencing of PCR products. The phylogenetic analysis showed that BCoV strains ABT/16/BF/Bocv183, ABT/BF/16/Bocv164 and ABT/BF/16/Bocv86 have close association with bovine strains from USA and Japan. However, ABT/BF/16/Bocv167 strain formed a s eparate clad along with camelid coronavirus strains and revealed the cross species transmission from camel to bovine. To the best of our knowledge this is the first report of interspecies transmission of coronavirus form camel to bovine.

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Bok, Marina, Celina G. Vega, Matias Castells, Rodney Colina, Andrés Wigdorovitz, and Viviana Parreño. "Development of an IgY-Based Treatment to Control Bovine Coronavirus Diarrhea in Dairy Calves." Viruses 15, no. 3 (March 9, 2023): 708. http://dx.doi.org/10.3390/v15030708.

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Анотація:

Bovine Coronavirus (BCoV) is a major pathogen associated with neonatal calf diarrhea. Standard practice dictates that to prevent BCoV diarrhea, dams should be immunized in the last stage of pregnancy to increase BCoV-specific antibody (Ab) titers in serum and colostrum. For the prevention to be effective, calves need to suck maternal colostrum within the first six to twelve hours of life before gut closure to ensure a good level of passive immunity. The high rate of maternal Ab transfer failure resulting from this process posed the need to develop alternative local passive immunity strategies to strengthen the prevention and treatment of BCoV diarrhea. Immunoglobulin Y technology represents a promising tool to address this gap. In this study, 200 laying hens were immunized with BCoV to obtain spray-dried egg powder enriched in specific IgY Abs to BCoV on a large production scale. To ensure batch-to-batch product consistency, a potency assay was statistically validated. With a sample size of 241, the BCoV-specific IgY ELISA showed a sensitivity and specificity of 97.7% and 98.2%, respectively. ELISA IgY Abs to BCoV correlated with virus-neutralizing Ab titers (Pearson correlation, R2 = 0.92, p < 0.001). Most importantly, a pilot efficacy study in newborn calves showed a significant delay and shorter duration of BCoV-associated diarrhea and shedding in IgY-treated colostrum-deprived calves. Calves were treated with milk supplemented with egg powder (final IgY Ab titer to BCoV ELISA = 512; VN = 32) for 14 days as a passive treatment before a challenge with BCoV and were compared to calves fed milk with no supplementation. This is the first study with proof of efficacy of a product based on egg powder manufactured at a scale that successfully prevents BCoV-associated neonatal calf diarrhea.

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Pratelli, Annamaria, Maria Stella Lucente, Marco Cordisco, Stefano Ciccarelli, Roberta Di Fonte, Alessio Sposato, Viviana Mari, et al. "Natural Bovine Coronavirus Infection in a Calf Persistently Infected with Bovine Viral Diarrhea Virus: Viral Shedding, Immunological Features and S Gene Variations." Animals 11, no. 12 (November 23, 2021): 3350. http://dx.doi.org/10.3390/ani11123350.

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The evolution of a bovine coronavirus (BCoV) natural infection in a calf persistently infected with bovine viral diarrhea virus (BVDV) was described. The infected calf developed intermittent nasal discharge, diarrhea and hyperthermia. The total number of leukocytes/mL and the absolute differential number of neutrophils and lymphocytes resulted within the normal range, but monocytes increased at T28 (time 28 post-infection). Flow-cytometry analysis evidenced that the CD8+ subpopulation increased at T7 and between T28 and T35. BCoV shedding in nasal discharges and feces was detected up to three weeks post infection and high antibody titers persisted up to T56. The RNA BCoV load increased until T14, contrary to what was observed in a previous study where the fecal excretion of BCoV was significantly lower in the co-infected (BCoV/BVDV) calves than in the calves infected with BCoV only. We can suppose that BVDV may have modulated the BCoV infection exacerbating the long viral excretion, as well as favoring the onset of mutations in the genome of BCoV detected in fecal samples at T21. An extensive study was performed to verify if the selective pressure in the S gene could be a natural mode of variation of BCoV, providing data for the identification of new epidemic strains, genotypes or recombinant betacoronaviruses.

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Zhukhovitsky, Vladimir, Natalia Shevlyagina, Margarita Zubasheva, Leonid Russu, Vladimir Gushchin, Gennady Meerovich, and Marina Strakhovskaya. "Infectivity and Morphology of Bovine Coronavirus Inactivated In Vitro by Cationic Photosensitizers." Viruses 14, no. 5 (May 15, 2022): 1053. http://dx.doi.org/10.3390/v14051053.

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Анотація:

Bovine coronaviruses (BCoVs), which cause gastrointestinal and respiratory diseases in cattle, and are genetically related to the human coronavirus HCoV-OC43, which is responsible for up to 10% of common colds, attract increased attention. We applied the method of photodynamic inactivation with cationic photosensitizers (PSs) to reduce the titers of BCoV and studied the morphological structure of viral particles under various modes of photodynamic exposure. The samples of virus containing liquid with an initial virus titer of 5 Log10 TCID50/mL were incubated with methylene blue (MB) or octakis(cholinyl)zinc phthalocyanine (Zn-PcChol8+) at concentrations of 1–5 μM for 10 min in the dark at room temperature. After incubation, samples were irradiated with LED (emission with maximum at 663 nm for MB or at 686 nm for Zn-PcChol8+) with light doses of 1.5 or 4 J/cm2. Next, the irradiation titrated virus containing liquid was studied using negative staining transmission electron microscopy. MB and Zn-PcChol8+ at concentrations of 1–5 μM, in combination with red light from LED sources in the low doses of 1.5–4.0 J/cm2, led to a decrease in BCoV titers by at least four orders of magnitude from the initial titer 5 Log10 TCID50/mL. Morphological changes in photodamaged BCoVs with increasing PS concentrations were loss of spikes, change in shape, decreased size of virus particles, destruction of the envelope, and complete disintegration of viruses. BCoV has been found to be sensitive to MB, which is the well-known approved drug, even in the absence of light.

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Lin, Ching-Hung, Cheng-Yao Yang, Meilin Wang, Shan-Chia Ou, Chen-Yu Lo, Tsung-Lin Tsai, and Hung-Yi Wu. "Effects of Coronavirus Persistence on the Genome Structure and Subsequent Gene Expression, Pathogenicity and Adaptation Capability." Cells 9, no. 10 (October 19, 2020): 2322. http://dx.doi.org/10.3390/cells9102322.

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Coronaviruses are able to establish persistence. However, how coronaviruses react to persistence and whether the selected viruses have altered their characteristics remain unclear. In this study, we found that the persistent infection of bovine coronavirus (BCoV), which is in the same genus as SARS-COV-2, led to alterations of genome structure, attenuation of gene expression, and the synthesis of subgenomic mRNA (sgmRNA) with a previously unidentified pattern. Subsequent analyses revealed that the altered genome structures were associated with the attenuation of gene expression. In addition, the genome structure at the 5′ terminus and the cellular environment during the persistence were responsible for the sgmRNA synthesis, solving the previously unanswered question regarding the selection of transcription regulatory sequence for synthesis of BCoV sgmRNA 12.7. Although the BCoV variants (BCoV-p95) selected under the persistence replicated efficiently in cells without persistent infection, its pathogenicity was still lower than that of wild-type (wt) BCoV. Furthermore, in comparison with wt BCoV, the variant BCoV-p95 was not able to efficiently adapt to the challenges of alternative environments, suggesting wt BCoV is genetically robust. We anticipate that the findings derived from this fundamental research can contribute to the disease control and treatments against coronavirus infection including SARS-CoV-2.

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Shakya, Ruchika, Alejandro Jiménez-Meléndez, Lucy J. Robertson, and Mette Myrmel. "Bovine Enteroids as an In Vitro Model for Infection with Bovine Coronavirus." Viruses 15, no. 3 (February 27, 2023): 635. http://dx.doi.org/10.3390/v15030635.

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Bovine coronavirus (BCoV) is one of the major viral pathogens of cattle, responsible for economic losses and causing a substantial impact on animal welfare. Several in vitro 2D models have been used to investigate BCoV infection and its pathogenesis. However, 3D enteroids are likely to be a better model with which to investigate host–pathogen interactions. This study established bovine enteroids as an in vitro replication system for BCoV, and we compared the expression of selected genes during the BCoV infection of the enteroids with the expression previously described in HCT-8 cells. The enteroids were successfully established from bovine ileum and permissive to BCoV, as shown by a seven-fold increase in viral RNA after 72 h. Immunostaining of differentiation markers showed a mixed population of differentiated cells. Gene expression ratios at 72 h showed that pro-inflammatory responses such as IL-8 and IL-1A remained unchanged in response to BCoV infection. Expression of other immune genes, including CXCL-3, MMP13, and TNF-α, was significantly downregulated. This study shows that the bovine enteroids had a differentiated cell population and were permissive to BCoV. Further studies are necessary for a comparative analysis to determine whether enteroids are suitable in vitro models to study host responses during BCoV infection.

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Wensman, Jonas Johansson, and Maria Stokstad. "Could Naturally Occurring Coronaviral Diseases in Animals Serve as Models for COVID-19? A Review Focusing on the Bovine Model." Pathogens 9, no. 12 (November 26, 2020): 991. http://dx.doi.org/10.3390/pathogens9120991.

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Анотація:

The current pandemic of COVID-19 has highlighted the importance of basic studies on coronaviruses (CoVs) in general, and severe acute respiratory syndrome CoV type 2 (SARS-CoV-2) in particular. CoVs have for long been studied in veterinary medicine, due to their impact on animal health and welfare, production, and economy. Several animal models using coronaviral disease in the natural host have been suggested. In this review, different animal models are discussed, with the main focus on bovine CoV (BCoV). BCoV is endemic in the cattle population worldwide and has been known and studied for several decades. SARS-CoV-2 and BCoV are both betacoronaviruses, where BCoV is highly similar to human coronavirus (HCoV) OC43, encompassing the same virus species (Betacoronavirus 1). BCoV causes respiratory and gastrointestinal disease in young and adult cattle. This review summarizes the current knowledge of the similarities and dissimilarities between BCoV and SARS-CoV-2, as well as discussing the usage of BCoV as a model for human CoVs, including SARS-CoV-2.

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Більше джерел

Дисертації з теми "Bcov"

Souza, Sibele Pinheiro de. "Um estudo sobre a diversidade molecular dos genes S e HE de Coronavírus bovino (BCoV)." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-04062013-112008/.

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Coronavírus bovino (BCoV) é o agente causador de doença, tanto entérica como respiratória em bovinos, mas até agora existem controvérsias sobre a relação genealógica entre as amostras de BCoV em diferentes tecidos. Neste estudo, amostras de fezes e secreções nasais de 14 vacas de um mesmo rebanho apresentando simultaneamente disenteria epizoótica e doença respiratória foram estudados quanto a presença de BCoV. As amostras virais detectadas tiveram tanto o gene de espícula (S) como o gene hemaglutinina-esterase (HE) parcialmente sequenciados. Para o gene HE, foram obtidas 12 sequências de secreções nasais e 12 de amostras de fezes e para o gene S, foram obtidas 14 sequências de secreções nasais e 12 de amostras de fezes, com 100% de identidade nucleotídica para cada gene para as amostras deste estudo. Estes resultados apresentam algumas divergências com estudos anteriores os quais relatam que linhagens diferentes de BCoV podem ser esperados em casos de disenteria e doença respiratória em vacas, pois linhagens com sequências idênticas dos genes S e HE podem não mostrar diferenças em relação tropismo pelos diferentes tecidos. Sequências completas de duas amostras brasileiras de BCoV mostram que o já descrito padrão filogeográfico baseado no sequenciamento do gene S parcial foi mantido, foram encontradas substituições de aminoácidos específicos.
Bovine coronavirus (BCoV) is the causative agent of both enteric and respiratory disease in cattle, but hitherto there were some controversy on the genealogic relationship amongst strains from these different tissues. In this study, samples of feces and nasal secretions of 14 cows from a same herd simultaneously presenting epizootic dysentery and respiratory disease were screened for BCoV and the strains detected had both the spike (S) and hemagglutinin-esterase (HE) genes partially sequenced. For HE gene, 12 sequences from nasal secretions and 12 from fecal samples were obtained and for S gene, 14 sequences from nasal secretions and 12 from fecal samples were obtained, with 100% nucleotide identities for each gene for the strains of this study. These results have some disagreements with previous reports which try to put forward that divergent BCoV strain should be expected in cases of dysentery and respiratory disease in cows, showing that strain with identical S and HE sequences might show no differences in tropisms. Complete S gene sequences of two Brazilian BCoV strains show that the already described phylogeographic pattern based on partial S gene is sustained, though specific amino acids subtitutions are found.

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Kin, Nathalie. "Caractérisation moléculaire intraspécifique et phylogénie comparée de deux Betacoronavirus de clade A : HCoV-OC43 et BCoV." Caen, 2015. http://www.theses.fr/2015CAEN2068.

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Анотація:

Les coronavirus sont caracterises par un potentiel evolutif important par l’intermediaire de recombinaisons genetiques et de mutations ponctuelles. Ces evenements peuvent avoir pour consequences l’emergence reussie d’un nouveau variant dans une nouvelle population hote, apres un franchissement de barriere d’espece. L’un de ces franchissement inter-especes a eu lieu a la fin du xixeme siecle avec l’emergence du hcov-oc43 a partir du bcov. Le genotypage du hcov-oc43 a permis de mettre en evidence une diversification intraspecifique en de nombreux genotypes incluant des genotypes recombinants. Parallelement, le genotypage du bcov n’a pas permis d’observer d’evenements de recombinaisons. Cependant, nous avons observe une organisation des bcov selon une distribution geographique avec un cluster amerique/asie et un cluster europe. L’emergence d’un coronavirus dans la population humaine a partir d’un reservoir animal doit faire l’objet d’une surveillance, comme le montre l’emergence du sars-cov et le mers-cov, a l’origine d’epidemies associees a des mortalites globales d’environ 10% et 40% respectivement
Coronaviruses are characterized by an important evolutionary potential by genetic recombination and single nucleotide polymorphisms. These events could lead to the successful emergence of a new variant in a new host population, following a species barrier crossing. One such event occurred at the end of the 19th century, with the emergence of hcov-oc43 from bcov. Genotyping of hcov-oc43 has made it possible to show an intraspecific diversification into numerous genotypes, including recombinant variants. In parallel, genotyping of bcov did not reveal recombinant events. However, we observed an organization of bcov with a geographical distribution, with a european cluster and an american/asian cluster. There is a need for monitoring the emergence of coronaviruses in the human population from an animal reservoir, such as has been seen in the emergence of sars-cov and mers-cov at the origin of epidemics associated with global mortality rates of around 10% and 40%, respectively

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Sonza, Sabrina. "Disenteria de inverno: detecção de coronavírus bovino (BCoV) por reação de PCR dirigida ao gene Rp Rd e isolamento em cultivo celular de HRT-18G." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-11072007-111349/.

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Анотація:

Coronavirus bovino (BCoV), um membro da família i>Coronaviridae, causa severa diarréia em bezerros neonatos e tem sido associado a diarréias de inverno em vacas leiteiras em vários paises, incluindo o Brasil. A morbidade da disenteria de inverno e alta chegando ate 100% , sendo um fator importante para economia já que causa queda da produção leiteira, levando a grandes perdas as criações de vacas leiteiras. O objetivo deste trabalho foi pesquisar a ocorrência de BCoV em vacas, diagnosticando amostras positivas por RT-PCR gene Rp Rd e isolando estas amostras positivas em células da linhagem HRT-18G. As amostras de fecais foram obtidas de 43 vacas leiteiras com disenteria de 8 propriedades dos Estados de São Paulo e Minas Gerais, Brasil. Das dez (10/43=23%) amostras positivas para esta técnica, 7 foram inoculadas em células da linhagem HRT-18G, sendo que o isolamento foi comprovado pela mesma técnica após seis passagens seriadas em 4 inoculações. Com isso, mostra-se que o BCoV também esta envolvido em disenterias de inverno em vacas leiteiras no Brasil. E através de isolamentos deste vírus, podemos contribuir para estudos continuados ajudar no esclarecimento de sua epidemiologia e possibilitar com um banco de vírus a prevenção de ordem também especifica da enfermidade.
Bovine coronavirus (BCoV), a member of Coronaviridae family, causes severe diarrhea in newborn calves and has been associated with outbreaks of winter dysentery (WD) in adult cattle in several countries, including Brazil. The morbidity rate of WD is very high (50-100%) and the disease causes severe economic losses once it decreases milk production. The aim of the present study was to survey for the occurrence of BCoV in cows using a RT-PCR targeted to the replicase gene and to isolate positive samples in HRT-18G cells. The fecal samples were obtained from 43 adult dairy cows with dysentery from São Paulo and Minas Gerais States, Brazil. Ten (23%) of the 43 fecal samples were positive for BCoV and 7 of these were inoculated in HRT-18G cells, when the isolation of 4 samples was proved by RT-PCR after sex passages. These findings indicate that BCoV is also involved in outbreaks of dysentery in adult cattle in Brazil. This shows the importance of more comprehensive studies on coronavirus in dairy cattle in the surveyed area and, with the isolation of the virus strains studied herein, one may contribute to other studies to enlighten the epidemiology and prevention of the disease.

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Palczewski, Grzegorz. "Mammalian Carotenoid Metabolism." Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1467993233.

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Souza, Sibele Pinheiro de. "Epidemiologia molecular em um surto de disenteria de inverno em bovinos leiteiros adultos no Estado de São Paulo e descrição de genótipos para o Coronavírus bovino (BCoV)." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-10022009-094446/.

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O coronavírus bovino (BCoV) é classificado no Grupo 2 do gênero Coronavirus da ordem Nidovirales, família Coronaviridae, causando disenteria (disenteria de inverno) em bovinos adultos, diarréia em bezerros neonatos e processos respiratórios em bovinos adultos e jovens. No presente estudo, 21 amostras fecais de vacas leiteiras colhidas durante um surto de disenteria em uma propriedade de Paranapanema no Estado de São Paulo positivas para BCoV foram submetidas a reações de PCR para amplificação parcial dos genes codificadores das proteínas S (448pb) e HE (441pb) do BCoV. Destas amostras, 14 foram positivas para cada PCR (não simultaneamente), sendo os fragmentos amplificados submetidos a seqüenciamento de DNA para reconstrução genealógica por máxima parcimônia através de algoritmo heurístico em conjunto com seqüências homólogas recuperadas do GenBank. Considerando-se o gene S, a identidade de nucleotídeos entre as 14 amostras aqui estudadas foi de 100%, tendo as mesmas segregado em um grupo exclusivo; além disso, demais amostras brasileiras incluídas no estudo segregam em outros dois grupos. Em relação ao gene HE, as 14 amostras estudadas apresentaram identidade de nucleotídeos de 100%, mas a árvore genealógica apresentou topologia pouco resolvida, tendo estas amostras, segregado em grupo politômico com as seqüências homólogas incluídas. Comparações entre os diversos grupos nas árvores do gene S em termos de aminoácidos revelaram marcadores grupo-específicos, com substituições exclusivas para as amostras de BCoV aqui estudadas. Com base nestes resultados, conclui-se que, durante o transcorrer do surto de disenteria de inverno, uma única linhagem de BCoV estava presente, baseado no seqüenciamento parcial dos genes S e HE e que há pelo menos três genótipos de BCoV presentes no Brasil em relação ao gene S e ao menos um em relação ao gene HE, considerando-se as regiões gênicas e as seqüências incluídas no presente estudo.
Bovine coronavirus (BCoV) is classified in group 2 of the genus Coronavirus, family Coronaviridae, order Nidovirales, and causes winter dysentery in adult bovine, neonatal calf diarrhea, and respiratory disorders in both adult and young bovine. In this investigation, 21 fecal samples from dairy cows collected during an outbreak of dysentery in a farm located at Paranapanema, São Paulo State, all positive to BCoV, were submitted to PCRs to partial amplification of genes S (448bp) and HE (441bp ) of BCoV. Fourteen out of these samples were positive for each PCR (not simultaneously) and the amplicons were submitted to DNA sequencing for genealogic reconstruction with maximum parsimony and heuristic algorithm with homologous sequences retrieved from the GenBank. Regarding S gene, the nucleotide identity among the 14 strains was 100% and these segregated in an exclusive cluster; furthermore, the other Brazilian strains included in the analysis segregated in other two clusters. Taking into account the HE gene, the 14 strains analyzed presented a nucleotide identity of 100%, but the genealogic tree showed a low-resolved topology, having these samples segregated in a polytomic cluster with the homologous sequences included. Amino acid comparisons among the different clusters in the trees of gene S revealed cluster-specific markers, with exclusive substitutions for the BCoV strains studied herein. Based on these results, one can conclude that, during the winter dysentery outbreak, a single BCoV lineage was involved based on partial S and HE genes sequences and that there are at least three genotypes of BCoV in Brazil regarding S gene and at least one regarding HE gene, taking into account the gene regions and the sequences included in this investigation.

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Kelly, Mary E. Kelly. "Mechanisms Controlling Vitamin A Homeostasis in the Gut and Periphery." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1528476852462429.

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Reed, Vanessa M. "β-Carotene 15,15’ Oxygenase-1 (BCO1) and β-Carotene 9,10’ Oxygenase-2 (BCO2) Distribution in Cells From Rat Liver and Intestine". The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1385997370.

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Brandão, Paulo Eduardo. "Coronavírus bovino (BCoV): ocorrência, diversidade molecular e padronização de PCR para diagnóstico a partir de amostras fecais de bezerros com e sem diarréia criados em municípios dos Estados de São Paulo e Minas Gerais, Brasil." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-30072004-090310/.

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O coronavírus bovino (BCoV) é classificado no grupo 2 do gênero Coronavirus da ordem Nidovirales, família Coronaviridae, causando diarréia em bezerros neonatos, processos respiratórios em bezerros não neonatos e disenteria em vacas adultas. No presente estudo, 203 amostras fecais de bezerros de 19 propriedades leiteiras nos Estados de São Paulo e Minas Gerais foram submetidas à prova de hemaglutinação/ inibição da hemaglutinação (HA/HI) para a detecção de coronavírus e a uma reação de PCR dirigida ao gene codificador da RNA-polimerase RNA-dependente dos coronavírus (PCR pol), sendo feita a comparação entre as duas técnicas através dos testes Kappa e J de Youden. Amostras positivas à PCR pol foram submetidas a uma reação de PCR para amplificação de um segmento de 488 pares de bases correspondentes à região hipervariável do gene codificador da subunidade S1 da proteína S, sendo os fragmentos submetidos a seqüenciamento de DNA para a reconstrução genealógica das amostras estudadas. Ainda, a presença de rotavírus foi pesquisada pela técnica de PAGE. Segundo a técnica de HA/ HI, 35,47% das amostras e 73,68% das propriedades rurais forma positivas para BCoV, enquanto que pela PCR pol 25,12% das amostras e 52,63% das propriedades rurais foram positivas para este vírus. A comparação entre as duas técnicas resultou valores de kappa de -0,048 para os resultados individuais e -0,08 em relação às propriedades rurais e J de Youden de -0,045 para os resultados individuais e -0,1 em relação às propriedades rurais, demonstrando baixa concordância entre as duas provas. A genealogia obtida por máxima parcimônia através de algoritmo heurístico e baseada em seqüências da região hipervariável do gene codificador da subunidade S1 da proteína S de 15 amostras de campo aqui estudadas, da amostra Kakegawa de coronavírus bovino utilizada como controle positivo e de 10 seqüências recuperadas dos GenBank revelou a existência de dois genotipos dentro desta espécie viral, sendo os dois genotipos encontrados entre amostras brasileiras. A identidade média de nucleotídeos entre as 15 amostras brasileiras foi de 98,34%, com similaridade média de aminoácidos de 98%. Amostras pertencentes ao genotipo 2 apresentaram uma deleção de 18 nucleotídeos/ 6 aminoácidos dentro da região correspondente ao domínio II da proteína S. A árvore de máxima parcimônia enraizada tendo bredavírus como grupo externo revelou que esta deleção ocorreu em um único momento na genealogia dos coronavírus bovinos. Rotavírus foi encontrado em 12,6% das amostras fecais individuais e 28, 57% das propriedades rurais pesquisadas. Estes resultados são os primeiros baseados em amostras brasileiras de coronavírus bovino e contribuem para a caracterização molecular do BCoV, para a predição da eficiência de imunógenos e para o encontro de marcadores moleculares úteis para estudos epidemiológicos continuados em relação às diarréias neonatais em bovinos.
Bovine coronavirus (BCoV) belongs to group 2 of the genus Coronavirus from the order Nidovirales, family Coronaviridae and causes diarrhea in newborn calves, respiratory diseases in non-newborn calves and dysentery in cows. In the present study, 203 stool samples of calves from 19 dairy farms from São Paulo and Minas Gerais States were submitted to hemagglutination/ hemagglutination inhibition test (HA/HI) to bovine coronavirus detection and a PCR assay targeted to the RNA-polymerase RNA-dependent gene of coronaviruses (PCR pol), the comparison between the two tests carried out with Kappa and Youden´s J tests. Samples positive to PCR pol were submitted to a PCR assay that amplifies a 488 base-pair fragment which corresponds to the hypervariable region of the gene coding for the S1 subunit of the S protein; the amplified fragments were submitted to DNA sequencing aiming the genealogic reconstruction of the studied samples. Rotavirus was surveyed with the PAGE test. The HA/ HI test resulted 35.47% of samples and 73.68% of farms positive to BCoV, while, according to PCR pol, 25.12% of the samples and 52.63% of the farms were positive to this virus. The comparison between the two tests produced a kappa value of -0.048 to individual results and -0.08 to the farms and Youden´s J value of -0.045 to individual results and -0.1 to the farms, showing low agreement between the two tests. Maximum parsimony genealogy with an heuristic algorithm based on sequences of the hypervariable region of the gene coding for the S1 subunit of the S protein from 15 field samples here studied, from the Kakegawa bovine coronavirus strain used as positive control and from 10 sequences retrieved from GenBank showed the existence of two genotypes in this viral species. Mean nucleotide identity between the 15 Brazilian samples was 98.34%, with mean amino acid similarity of 98%. Samples from genotype 2 showed a deletion of 18 nucleotides/ 6 amino acids inside the domain II region of the S protein. Rooted maximum parsimony tree with bredavirus as an outgroup revealed that this deletion has happened only once in bovine coronavirus genealogy. Rotavirus was found in 12.6 % of stool samples and 28.57% of the surveyed farms. These are the first results based on Brazilian strains of bovine coronavirus and contribute to molecular characterization of BCoV, to the prediction of the efficiency of immunogens and to the finding of molecular markers useful to continued epidemiologic surveys on newborn bovine diarrhea.

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Fleshman, Matthew Kintz. "β-Carotene Absorption and Metabolism". The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1313548706.

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Walton, Marguerite. "Mathematical requirements for first-year BCOM students at NMMU." Thesis, Nelson Mandela Metropolitan University, 2009. http://hdl.handle.net/10948/886.

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These studies have focused on identifying the mathematical requirements of first-year BCom students at Nelson Mandela Metropolitan University. The research methodology used in this quantitative study was to make use of interviewing, questionnaire investigation, and document analysis in the form of textbook, test and examination analysis. These methods provided data that fitted into a grounded theory approach. The study concluded by identifying the list of mathematical topics required for the first year of the core subjects in the BCom degree programme. In addition, the study found that learners who study Mathematics in the National Senior Certificate should be able to cope with the mathematical content included in their BCom degree programme, while learners studying Mathematical Literacy would probably need support in some of the areas of mathematics, especially algebra, in order to cope with the mathematical content included in their BCom degree programme. It makes a valuable contribution towards elucidating the mathematical requirements needed to improve the chances of successful BCom degree programme studies at South African universities. It also draws the contours for starting to design an efficient support course for future “at-risk” students who enter higher education studies.

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Книги з теми "Bcov"

Lehman, Carol M. BCOM. 2nd ed. Mason, OH: South-Western, 2009.

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School, Birmingham Business, ed. BCOM: BCOM with a language : business skills development. Birrmingham: Birmingham Business School, 1995.

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ja yi bstan bcos. Pe cin: Mi rigs dpe skrun khang, 2005.

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Ṅag-dbaṅ-kun-dgaʼ-bsod-nams, ʼJam-mgon A-myes-źabs, 1597-ca. 1662. та Źol-khaṅ Bsod-nams-dar rgyas, ред. Rol moʼi bstan bcos. Pe-cin: Mi rigs dpe skrun khaṅ, 1986.

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Keene, Raymond D., and G. K. Kasparov. BCO2 Batsford Chess Openings 2. 2nd ed. London: B.T. Batsford Ltd, 1997.

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He-ru-ka, Ñi-zla. Rten ʼbrel sngags bcos rig pa. Pe-cin: Mi-rigs Dpe-skrun Khang, 2015.

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Ma bcos sems kyi rlabs źags. Solan, H.P: [s.n., 2002.

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Hūm̐-chen та Ñi-zla, ред. Sṅags bcos beʼu bum phyogs bsgrigs. Lha-sa: Mi rigs dpe skrun khaṅ, 2006.

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al, Zha-lu-tsantra-shrI rt. Rol mo'i bstan bcos gces btus. Lha-sa: Bod ljongs bod yig dpe rnying dpe skrun khang, 2019.

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Center, Buddhist Digital Resource. Gso rig sman bcos phyogs bsgrigs. Zi ling: Mtsho sngon mi rigs dpe skrun khang, 2013.

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Kanazawa, Atsushi, and Jie Zhou. "Lectures on BCOV Holomorphic Anomaly Equations." In Calabi-Yau Varieties: Arithmetic, Geometry and Physics, 445–73. New York, NY: Springer New York, 2015. http://dx.doi.org/10.1007/978-1-4939-2830-9_13.

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Mocellin, Simone. "BCOR-Rearranged Sarcoma." In Soft Tissue Tumors, 125. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-58710-9_33.

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Bhattacharyya, Siddhartha, Partha Sarathi Banerjee, Amiya Karmakar, Debashis De, and Joel J. P. C. Rodrigues. "BCoT: Concluding Remarks." In Blockchain based Internet of Things, 289–93. Singapore: Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-9260-4_12.

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Zhang, Liang-Jie, Sheng He, Jing Zeng, Yishuang Ning, and Huan Chen. "BCOA: Blockchain Open Architecture." In Web Services – ICWS 2021, 90–111. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-96140-4_7.

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Wieten, G., R. C. Dorresteijn, M. C. Philippi, M. Habben-Jansen, G. De Clercq, and E. C. Beuvery. "Batch Control System Vaccines: BCSV." In Animal Cell Technology: Developments Towards the 21st Century, 1167–75. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0437-1_183.

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Teodorović, Dušan. "Bee Colony Optimization (BCO)." In Innovations in Swarm Intelligence, 39–60. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-04225-6_3.

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Saji, Amal C., V. V. Nandakishore, Akshay Vijayan, and John Prakash Joseph. "BCGV: Blockchain Enabled Certificate Generation, Verification and Storage." In Lecture Notes in Electrical Engineering, 349–55. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-1420-3_36.

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Erhard, Franz Xaver. "Don-grub rgyal: Sad kyis bcom pa'i me tog." In Kindlers Literatur Lexikon (KLL), 1–2. Stuttgart: J.B. Metzler, 2020. http://dx.doi.org/10.1007/978-3-476-05728-0_10957-1.

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Li, Chunmei, Lei Shang, Zheng Wei, Jun Ge, Mingyue Zhang, and Yun Fang. "Commodity-Tra: A Traceable Transaction Scheme Based on FISCO BCOS." In Communications in Computer and Information Science, 264–80. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-7242-3_17.

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Khatun, Mst Surma, Aofan Liu, and Mahdi H. Miraz. "BCoT-Based Smart Manufacturing: An Enhanced Precise Measurement Management System." In Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, 29–53. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-25161-0_3.

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Тези доповідей конференцій з теми "Bcov"

Huang, Penggui, Bi Huang, Youjie Zhao, Zhenping Qiang, and Minmin Qing. "BCoV: a covergence of blockchain and IoV." In 2020 IEEE 20th International Conference on Software Quality, Reliability and Security Companion (QRS-C). IEEE, 2020. http://dx.doi.org/10.1109/qrs-c51114.2020.00108.

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Weir, Richard F. ff. "3-Dimensional, Single Marker, Gait Analysis System." In ASME 1998 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/imece1998-0195.

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Abstract There is a wealth of data that can be obtained by recording the 3-D position of a single marker at the approximate level of the body center of mass (BCOM) during walking. Evolving the design of a previous 1-D single marker gait system (Weir & Childress, 1997) we are developing a portable, easy-to-use, real-time system which will measure the position of the BCOM during walking in 3-D. This system will measure instantaneous anterior-posterior, medial-lateral, and vertical displacements of the BCOM. We plan to use these data to measure and estimate gait parameters and symmetry indices.

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Zhang, Michelle Garying, Dawn Owens, Stefan Kurtenbach, Jeffim Kuznetsov, Matthew Fields, Daniel Pelaez, and James W. Harbour. "Abstract 3027: Role of BCOR in retinoblastoma." In Proceedings: AACR Annual Meeting 2021; April 10-15, 2021 and May 17-21, 2021; Philadelphia, PA. American Association for Cancer Research, 2021. http://dx.doi.org/10.1158/1538-7445.am2021-3027.

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Yu, Zhengxu, Zhongming Jin, Long Wei, Jishun Guo, Jianqiang Huang, Deng Cai, Xiaofei He, and Xian-Sheng Hua. "Progressive Transfer Learning for Person Re-identification." In Twenty-Eighth International Joint Conference on Artificial Intelligence {IJCAI-19}. California: International Joint Conferences on Artificial Intelligence Organization, 2019. http://dx.doi.org/10.24963/ijcai.2019/586.

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Model fine-tuning is a widely used transfer learning approach in person Re-identification (ReID) applications, which fine-tuning a pre-trained feature extraction model into the target scenario instead of training a model from scratch. It is challenging due to the significant variations inside the target scenario, e.g., different camera viewpoint, illumination changes, and occlusion. These variations result in a gap between the distribution of each mini-batch and the distribution of the whole dataset when using mini-batch training. In this paper, we study model fine-tuning from the perspective of the aggregation and utilization of the global information of the dataset when using mini-batch training. Specifically, we introduce a novel network structure called Batch-related Convolutional Cell (BConv-Cell), which progressively collects the global information of the dataset into a latent state and uses this latent state to rectify the extracted feature. Based on BConv-Cells, we further proposed the Progressive Transfer Learning (PTL) method to facilitate the model fine-tuning process by joint training the BConv-Cells and the pre-trained ReID model. Empirical experiments show that our proposal can improve the performance of the ReID model greatly on MSMT17, Market-1501, CUHK03 and DukeMTMC-reID datasets. The code will be released later on at \url{https://github.com/ZJULearning/PTL}

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Mehta, Parikshit, and Nader Jalili. "Vibration Analysis of Thin Plates Subject to Piezoelectric Actuation: A New Perspective in Modeling and Numerical Analysis." In ASME 2011 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/detc2011-47988.

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This paper undertakes model development and numerical simulations of vibration problem of piezoelectrically actuated thin plates with a holistic perspective. Constitutive laws governing piezoelectric actuator are integrated with the potential and kinetic energies of combined plate-actuator system. The equations of motions are derived using variational approach and verified with results obtained by Newton’s equilibrium approach. It is verified that the field coupled components associated with piezoelectric actuator appear as distributed moments over the area of the actuator. The equations of motion are solved using modal analysis deploying Raleigh Ritz method utilizing Boundary Characteristic Orthogonal Polynomials (BCOP). The shape functions generated using this method is used in Assumed Mode Method (AMM) to numerically simulate forced vibration analysis. Since Raleigh Ritz analysis with BCOP can be deployed with the plates of all the geometries, minor modifications in selecting the shape functions enables one to use the same method to calculate natural frequencies of annular plate as well.

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Wong, Fui Kent, Sulaiman Sidek, Samie Sok Foon Lee, Ridvan Akkurt, Yin Shi, Pakorn Tangtuengtin, Sanggeetha Kalidas, et al. "Automated System for Feature Petrophysical Data Engineering – Improves ML Behind Casing Opportunity Results in Highly Deviated Wells." In Offshore Technology Conference Asia. OTC, 2024. http://dx.doi.org/10.4043/34871-ms.

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Abstract Assessing the remaining hydrocarbon potential in highly deviated wells in Malaysia Field is challenging because it is difficult to deploy logging operations because of the wellbore angle. To address this challenge, a machine learning (ML) model is adopted to predict behind-casing opportunity (BCO) results using field data. The ML model is integrated into the Production Enhancement Candidate Generation and Screening (PECGS) artificial intelligence (AI) workflow, which aims to identify new candidates for enhancing production. High-quality petrophysical properties and production history data are essential input features to implement this methodology. Before executing the ML model, numerous efforts to perform feature engineering on the data are needed to ensure the high accuracy of the BCO prediction. Understanding the difficulty level of these work steps reveals that extracting the required features from petrophysical data for multiple fields involves many tedious manual steps. These steps are time-consuming and can lead to errors with repetitive and monotonous tasks for hundreds of wells. An automated system is developed to minimize manual human intervention and improve data accuracy. This paper presents a novel data science approach to accelerate the petrophysical data feature engineering process. This involves automating the petrophysical data preprocessing and quality control (QC) steps. Such automation offers high-quality well data and reservoir properties such as well trajectory, average porosity, net pay thickness, and the permeability thickness (Kh) used to predict BCO. An automated system incorporating comprehensive data analytics and quantile regression forest (QRF) techniques was developed. The system carries out the well data inventory, trajectory verification, formation evaluation result consistency check, and auto compilation of transformed petrophysical features. Once data analytics is incorporated into the system, within a few minutes it can output comprehensive well inventory reports that verify the well trajectories for a massive number of wells in a field. The QRF algorithm also helps rank the consistency and uncertainty of formation evaluation results across the field, which eventually guides the petrophysicist in determining the best result for reservoir properties summary computation. Additional validation process benefits enable missed pay detection, providing petrophysical results in zones with previous data gaps. In the final stage, the system also automatically sorts out a structured output that combines properties for multiple production zones to facilitate the usage across the ML BCO workflow. This automated system offers better efficiency in feature extraction and more accurate answers in BCO prediction. One of the experiment fields has successfully increased the registered BCO candidates in highly deviated wells with the improved reservoir properties availability that result from the automated system. The solutions were applied to 24 additional fields in the Malaysia region. An estimated time savings of 500 hours was achieved in generating the highest quality reservoir properties ready to be used in ML BCO. The saved hours also translated into energy savings in computing power and drive toward a net-zero carbon footprint acceleration with a reduction of ~75 kg of CO2 emissions.

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TUMAŠEVIČIŪTĖ, Rasa, and Aušra ZIGMONTIENĖ. "DAUGIAKRITERĖS ANALIZĖS TVARIAM BIOLOGINIŲ ATLIEKŲ TVARKYMUI TAIKYMAS." In Conference for Junior Researchers „Science – Future of Lithuania“. VGTU Technika, 2018. http://dx.doi.org/10.3846/aainz.2018.022.

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Tarptautinis, taip pat ir Lietuvos, atliekų tvarkymo sektorius susiduria su naujais iššūkiais, spręsdamas politinius tvaraus atliekų tvarkymo klausimus, skatindamas naujų atliekų apdorojimo technologijų plėtrą ir ruošdamas didelio masto pertvarką atliekų sektoriuje. Atliekų tvarkymo taisyklėse numatyta, kad nuo 2019 m. visi miestai, turintys daugiau nei 50 000 gyventojų, privalės atskirai iš savo gyventojų surinkti biologines atliekas. Valstybei tampa aktualu tinkamai įvertinti biologinių atliekų tvarkymo technologijų poveikį aplinkai. Šiame straipsnyje biologinių atliekų vadybos aplinkosauginis poveikis nagrinėjamas naudojant būvio ciklo vertinimo (toliau – BCV) metodą. Problemos kompleksiškumui įvertinti ir analizuoti pritaikytas kompleksinis daugiakriteris vertinimo metodas ir pasitelktas aukštos kvalifikacijos specialistų (ekspertų) dalyvavimas. Pasitelkus BCV ir ekspertų kriterijų įvertinimo duomenis, įvertintas aplinkosauginis klimato atšilimo potencialas per 100 metų, rūgštėjimo, eutrofikacijos, fotocheminis ozono susikūrimo, ozono sluoksnio mažėjimo, abiotinio nykimo, toksiškumo žmogui ir sausumos ekotoksiškumo potencialai. BCV atliktas, remiantis EcoInvent 2.2 duomenų baze ir pasiekiamais regioniniais duomenimis. Ekspertų nuomonių suderinamumas įvertintas naudojant Kendelo konkordacijos koeficientą. Bendri duomenys apdoroti pasinaudojant COPRAS metodu. Gauti rezultatai parodė, kad geriausias biologinių atliekų tvarkymo būdas – anaerobinis perdirbimas su vėlesniu kompostavimo etapu, mažiau naudingas kompostavimas įrenginiuose – 58,98 %, o prasčiausias – biologinių atliekų deginimas (16,58 %).

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Li, Jiachen, Bin Wang, Shiqiang Zhu, Xin Cao, Fan Zhong, Wenxuan Chen, Te Li, Jason Gu, and Xueying Qin. "BCOT: A Markerless High-Precision 3D Object Tracking Benchmark." In 2022 IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR). IEEE, 2022. http://dx.doi.org/10.1109/cvpr52688.2022.00658.

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Yadav, Abhay Kumar, and Virendra Prasad Vishwakarma. "Adoptation of Blockchain of Things(BCOT): Oppurtunities & Challenges." In 2022 IEEE International Conference on Blockchain and Distributed Systems Security (ICBDS). IEEE, 2022. http://dx.doi.org/10.1109/icbds53701.2022.9935985.

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Fadhil, Imran M., Jamari M. Shah, Salmi Sansudin, Asaad Abdollahzadeh, Husni Husiyandi, Nur Aimi Azimah Azizul, Fairuz Hidayah Hasnan, and Yuan Jiun Thai. "Identifying New Behind Casing Opportunities Using Machine Learning." In SPE Reservoir Characterisation and Simulation Conference and Exhibition. SPE, 2023. http://dx.doi.org/10.2118/212627-ms.

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Abstract This paper discusses the adoption of Machine Learning (ML) approach to identify new Behind Casing Opportunities (BCO) in two brown fields (B and S) offshore East Malaysia. A multi-stage field-based ML models were developed based on selected wells and consequently used to predict reservoir characteristics in completed wells. The predicted results indicated new upside BCO for add perforation candidate. Raw and interpreted data from B and S fields were analyzed and processed for model training and evaluation. For the case of identifying new opportunity, a specific model development strategy and train dataset selection was employed. The trained ML models evaluated to select the optimal models to predict lithologies, porosity, permeability and water saturations which are then been compared against the actual interpretation. Eventually, the identified upside potentials are validated by Subject Matter Experts (SME) before being proposed as add perforation candidate. It was observed that the models’ performances vary between the two fields due to unique geological complexity as well as the varying quality of raw and interpreted data from each field. Field B which is more geologically complex performs less compared to Field S. In conclusion, this study provides and insight on the advantages and limitations of machine learning to identify new upside BCO in completed wells. The novelty in this work is in the specific model development strategy to identify new upside BCO potentials. This work may be beneficial and essential especially in enhancing resource monetization in brown fields which face challenges in terms of high idle well percentage, low recovery, and declining production.

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Звіти організацій з теми "Bcov"

Soenen, Karen, Dana Gerlach, Christina Haskins, Taylor Heyl, Danie Kinkade, Sawyer Newman, Shannon Rauch, et al. How can BCO-DMO help with your oceanographic data? How can BCO-DMO help with your oceanographic data?, December 2021. http://dx.doi.org/10.1575/1912/27803.

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BCO-DMO curates a database of research-ready data spanning the full range of marine ecosystem related measurements including in-situ and remotely sensed observations, experimental and model results, and synthesis products. We work closely with investigators to publish data and information from research projects supported by the National Science Foundation (NSF), as well as those supported by state, private, and other funding sources. BCO-DMO supports all phases of the data life cycle and ensures open access of well-curated project data and information. We employ F.A.I.R. Principles that comprise a set of values intended to guide data producers and publishers in establishing good data management practices that will enable effective reuse.

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Kinkade, Danie. BCO-DMO: Surfing the Crests and Troughs of Data Sharing. Woods Hole Oceanographic Institution, March 2022. http://dx.doi.org/10.1575/1912/29174.

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Many of the challenges currently associated with sharing oceanographic data currently facing researchers and the repositories through which they share their data, are cultural rather than technical. This talk presents an overview of obstacles and opportunities related to data sharing within the oceanographic community.

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Barrios Ross, Armando, and Abelardo Daza. Un Estudio sobre la Autonomía Administrativa del Banco Central de Venezuela. Inter-American Development Bank, September 2000. http://dx.doi.org/10.18235/0011845.

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El propósito básico de este estudio es contribuir a la comprensión de los factores favorables y los elementos de potencial amenaza para que los bancos centrales ejerzan su autonomía institucional. Para el logro de este propósito, se utiliza la metodología de estudio de casos, examinando la experiencia de Venezuela durante dos eventos particulares: la crisis financiera acaecida en el período 1994-1996 y el manejo de la política cambiaria durante los años 1995-96. Ambos eventos sucedieron durante la vigencia de la Ley del Banco Central de Venezuela (BCV) reformada en 1992, mediante la cual se aspiró conferirle un grado significativo de autonomía frente a otras instituciones del Estado, particularmente el poder ejecutivo. Ello constituye un escenario natural para poner a prueba la autonomía institucional del BCV frente al gobierno y los diversos grupos a que está expuesta su actuación.

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Soenen, Karen, Danie Kinkade, Adam Shepherd, Mak A. Saito, Dana Gerlach, Lynne M. Merchant, Sawyer Newman, Shannon Rauch, and Amber York. Fitting square pegs into a round hole. Curating heterogeneous oceanographic data at BCO-DMO. Woods Hole Oceanographic Institution, February 2024. http://dx.doi.org/10.1575/1912/67676.

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BCO-DMO is a domain-specific repository containing 18 years of curated, heterogeneous oceanographic data. Data managers are at the core of the repository, applying the F.A.I.R. principles to every dataset coming in. This talk steers the audience through such a curated dataset, covering the advancements and challenges that comes with domain curation.

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Olivo, Víctor. Perspectiva histórica sobre el declive de la economía venezolana. Banco Interamericano de Desarrollo, August 2023. http://dx.doi.org/10.18235/0005067.

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El documento busca distinguir los elementos más importantes para explicar el colapso de la economía venezolana a partir de 2015. Se analizan las cifras macroeconómicas más relevantes para describir los determinantes de la crisis venezolana, con información desde 1950 o 1960 de acuerdo con la disponibilidad. A su vez, se labora la narrativa detrás del comportamiento de estos indicadores, particularmente durante los años previos a la crisis. El episodio registrado luego de 2015 se resume en una contracción económica y una aceleración inflacionaria sin precedentes en América Latina. Este se apalanca en la frágil institucionalidad fiscal-monetaria instaurada desde la nacionalización del petróleo. La caída del ingreso petrolero luego de 2004 no detuvo el crecimiento del gasto público, de modo que el chavismo terminó fundamentando su sistema económico en una indisciplina fiscal-monetaria que se hizo paso entre reformas legales que facilitaron el financiamiento monetario de la gestión fiscal, autorizando el otorgamiento de préstamos del BCV a una PDVSA que fue utilizada para actividades parafiscales. La evidencia empírica señala que los controles de precio, de cambio y de tasas de interés acompañados de una política fiscal y monetaria expansiva derivó en una caída del producto potencial.

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Neeley, Aimee, Stace E. Beaulieu, Chris Proctor, Ivona Cetinić, Joe Futrelle, Inia Soto Ramos, Heidi M. Sosik, et al. Standards and practices for reporting plankton and other particle observations from images. Woods Hole Oceanographic Institution, July 2021. http://dx.doi.org/10.1575/1912/27377.

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This technical manual guides the user through the process of creating a data table for the submission of taxonomic and morphological information for plankton and other particles from images to a repository. Guidance is provided to produce documentation that should accompany the submission of plankton and other particle data to a repository, describes data collection and processing techniques, and outlines the creation of a data file. Field names include scientificName that represents the lowest level taxonomic classification (e.g., genus if not certain of species, family if not certain of genus) and scientificNameID, the unique identifier from a reference database such as the World Register of Marine Species or AlgaeBase. The data table described here includes the field names associatedMedia, scientificName/ scientificNameID for both automated and manual identification, biovolume, area_cross_section, length_representation and width_representation. Additional steps that instruct the user on how to format their data for a submission to the Ocean Biodiversity Information System (OBIS) are also included. Examples of documentation and data files are provided for the user to follow. The documentation requirements and data table format are approved by both NASA’s SeaWiFS Bio-optical Archive and Storage System (SeaBASS) and the National Science Foundation’s Biological and Chemical Oceanography Data Management Office (BCO-DMO).

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