The Experts below are selected from a list of 71538 Experts worldwide ranked by ideXlab platform
Sylvie Cloutier - One of the best experts on this subject based on the ideXlab platform.
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ugt74s1 is the Key Player in controlling secoisolariciresinol diglucoside sdg formation in flax
BMC Plant Biology, 2017Co-Authors: Bourlaye Fofana, Kaushik Ghose, Jason Mccallum, Sylvie CloutierAbstract:Flax lignan, commonly known as secoisolariciresinol (SECO) diglucoside (SDG), has recently been reported with health-promoting activities, including its positive impact in metabolic diseases. However, not much was reported on the biosynthesis of SDG and its monoglucoside (SMG) until lately. Flax UGT74S1 was recently reported to sequentially glucosylate SECO into SMG and SDG in vitro. However, whether this gene is the only UGT achieving SECO glucosylation in flax was not known. Flax genome-wide mining for UGTs was performed. Phylogenetic and gene duplication analyses, heterologous gene expression and enzyme assays were conducted to identify family members closely related to UGT74S1 and to establish their roles in SECO glucosylation. A total of 299 different UGTs were identified, of which 241 (81%) were duplicated. Flax UGTs diverged 2.4–153.6 MYA and 71% were found to be under purifying selection pressure. UGT74S1, a single copy gene located on chromosome 7, displayed no evidence of duplication and was deemed to be under positive selection pressure. The phylogenetic analysis identified four main clusters where cluster 4, which included UGT74S1, was the most diverse. The duplicated UGT74S4 and UGT74S3, located on chromosomes 8 and 14, respectively, were the most closely related to UGT74S1 and were differentially expressed in different tissues. Heterologous expression levels of UGT74S1, UGT74S4 and UGT74S3 proteins were similar but UGT74S4 and UGT74S3 glucosylation activity towards SECO was seven fold less than UGT74S1. In addition, they both failed to produce SDG, suggesting neofunctionalization following their divergence from UGT74S1. We showed that UGT74S1 is closely related to two duplicated genes, UGT74S4 and UGT74S3 which, unlike UGT74S1, failed to glucosylate SMG into SDG. The study suggests that UGT74S1 may be the Key Player in controlling SECO glucosylation into SDG in flax although its closely related genes may also contribute to a minor extent in supplying the SMG precursor to UGT74S1.
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UGT74S1 is the Key Player in controlling secoisolariciresinol diglucoside (SDG) formation in flax
BMC Plant Biology, 2017Co-Authors: Bourlaye Fofana, Kaushik Ghose, Jason Mccallum, Frank M. You, Sylvie CloutierAbstract:Background Flax lignan, commonly known as secoisolariciresinol (SECO) diglucoside (SDG), has recently been reported with health-promoting activities, including its positive impact in metabolic diseases. However, not much was reported on the biosynthesis of SDG and its monoglucoside (SMG) until lately. Flax UGT74S1 was recently reported to sequentially glucosylate SECO into SMG and SDG in vitro. However, whether this gene is the only UGT achieving SECO glucosylation in flax was not known. Results Flax genome-wide mining for UGTs was performed. Phylogenetic and gene duplication analyses, heterologous gene expression and enzyme assays were conducted to identify family members closely related to UGT74S1 and to establish their roles in SECO glucosylation. A total of 299 different UGTs were identified, of which 241 (81%) were duplicated. Flax UGTs diverged 2.4–153.6 MYA and 71% were found to be under purifying selection pressure. UGT74S1 , a single copy gene located on chromosome 7, displayed no evidence of duplication and was deemed to be under positive selection pressure. The phylogenetic analysis identified four main clusters where cluster 4, which included UGT74S1 , was the most diverse. The duplicated UGT74S4 and UGT74S3 , located on chromosomes 8 and 14, respectively, were the most closely related to UGT74S1 and were differentially expressed in different tissues. Heterologous expression levels of UGT74S1, UGT74S4 and UGT74S3 proteins were similar but UGT74S4 and UGT74S3 glucosylation activity towards SECO was seven fold less than UGT74S1. In addition, they both failed to produce SDG, suggesting neofunctionalization following their divergence from UGT74S1 . Conclusions We showed that UGT74S1 is closely related to two duplicated genes, UGT74S4 and UGT74S3 which, unlike UGT74S1, failed to glucosylate SMG into SDG. The study suggests that UGT74S1 may be the Key Player in controlling SECO glucosylation into SDG in flax although its closely related genes may also contribute to a minor extent in supplying the SMG precursor to UGT74S1 .
Yves Zenou - One of the best experts on this subject based on the ideXlab platform.
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who is the Key Player a network analysis of juvenile delinquency
Journal of Business & Economic Statistics, 2020Co-Authors: Lungfei Lee, Xiaodong Liu, Eleonora Patacchini, Yves ZenouAbstract:This article presents a methodology for empirically identifying the Key Player, whose removal from the network leads to the optimal change in aggregate activity level in equilibrium [Ballester, C.,...
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Who is the Key Player? A Network Analysis of Juvenile Delinquency ∗†
Journal of Business & Economic Statistics, 2020Co-Authors: Lungfei Lee, Xiaodong Liu, Eleonora Patacchini, Yves ZenouAbstract:This article presents a methodology for empirically identifying the Key Player, whose removal from the network leads to the optimal change in aggregate activity level in equilibrium [Ballester, C.,...
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Key Player Policies When Contextual Effects Matter
The Journal of Mathematical Sociology, 2014Co-Authors: Coralio Ballester, Yves ZenouAbstract:We consider a model where the criminal decision of each individual is affected by not only her own characteristics, but also by the characteristics of her friends (contextual effects). We determine who the Key Player is, i.e. the criminal who once removed generates the highest reduction in total crime in the network. We generalize the intercentrality measure proposed by Ballester et al. (2006) by taking into account the change in contextual effects following the removal of the Key Player. We also provide an example that shows how the new formula can be calculated in practice.
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Key Players in Co-Offending Networks
2014Co-Authors: Matthew J. Lindquist, Yves ZenouAbstract:We study peer effects in crime by analyzing co-offending networks. We first provide a credible estimate of peer effects in these networks equal to 0.17. This estimate implies a social multiplier of 1.2 for those individuals linked to only one co-offender and a social multiplier of 2 for those linked to three co-offenders. We then provide one of the first empirical tests of the Key Player policy in a real world setting. This policy defines a micro-founded strategy for removing the criminal from each network that reduces total crime by the largest amount. Using longitudinal data, we are able to compare the theoretical predictions of the Key Player policy with real world outcomes. By focusing on networks for which the Key Player has disappeared over time, we show that the theoretical predicted crime reduction is close to what is observed in the real world. We also show that the Key Player policy outperforms other reasonable police policies such as targeting the most active criminals or targeting criminals who have the highest betweenness or eigenvector centrality in the network. This indicates that behavioral-based policies can be more efficient in reducing crime than those based on algorithms that have no micro-foundation.
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Criminal Networks: Who is the Key Player?
SSRN Electronic Journal, 2012Co-Authors: Xiaodong Liu, Yves Zenou, Eleonora Patacchini, Lungfei LeeAbstract:We analyze delinquent networks of adolescents in the United States. We develop a dynamic network formation model showing who the Key Player is, i.e. the criminal who once removed generates the highest possible reduction in aggregate crime level. We then structurally estimate our model using data on criminal behaviors of adolescents in the United States (AddHealth data). Compared to other criminals, Key Players are more likely to be male, have less educated parents, are less attached to religion and feel socially more excluded. We also find that, even though some criminals are not very active in criminal activities, they can be Key Players because they have a crucial position in the network in terms of betweenness centrality.
Kaushik Ghose - One of the best experts on this subject based on the ideXlab platform.
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ugt74s1 is the Key Player in controlling secoisolariciresinol diglucoside sdg formation in flax
BMC Plant Biology, 2017Co-Authors: Bourlaye Fofana, Kaushik Ghose, Jason Mccallum, Sylvie CloutierAbstract:Flax lignan, commonly known as secoisolariciresinol (SECO) diglucoside (SDG), has recently been reported with health-promoting activities, including its positive impact in metabolic diseases. However, not much was reported on the biosynthesis of SDG and its monoglucoside (SMG) until lately. Flax UGT74S1 was recently reported to sequentially glucosylate SECO into SMG and SDG in vitro. However, whether this gene is the only UGT achieving SECO glucosylation in flax was not known. Flax genome-wide mining for UGTs was performed. Phylogenetic and gene duplication analyses, heterologous gene expression and enzyme assays were conducted to identify family members closely related to UGT74S1 and to establish their roles in SECO glucosylation. A total of 299 different UGTs were identified, of which 241 (81%) were duplicated. Flax UGTs diverged 2.4–153.6 MYA and 71% were found to be under purifying selection pressure. UGT74S1, a single copy gene located on chromosome 7, displayed no evidence of duplication and was deemed to be under positive selection pressure. The phylogenetic analysis identified four main clusters where cluster 4, which included UGT74S1, was the most diverse. The duplicated UGT74S4 and UGT74S3, located on chromosomes 8 and 14, respectively, were the most closely related to UGT74S1 and were differentially expressed in different tissues. Heterologous expression levels of UGT74S1, UGT74S4 and UGT74S3 proteins were similar but UGT74S4 and UGT74S3 glucosylation activity towards SECO was seven fold less than UGT74S1. In addition, they both failed to produce SDG, suggesting neofunctionalization following their divergence from UGT74S1. We showed that UGT74S1 is closely related to two duplicated genes, UGT74S4 and UGT74S3 which, unlike UGT74S1, failed to glucosylate SMG into SDG. The study suggests that UGT74S1 may be the Key Player in controlling SECO glucosylation into SDG in flax although its closely related genes may also contribute to a minor extent in supplying the SMG precursor to UGT74S1.
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UGT74S1 is the Key Player in controlling secoisolariciresinol diglucoside (SDG) formation in flax
BMC Plant Biology, 2017Co-Authors: Bourlaye Fofana, Kaushik Ghose, Jason Mccallum, Frank M. You, Sylvie CloutierAbstract:Background Flax lignan, commonly known as secoisolariciresinol (SECO) diglucoside (SDG), has recently been reported with health-promoting activities, including its positive impact in metabolic diseases. However, not much was reported on the biosynthesis of SDG and its monoglucoside (SMG) until lately. Flax UGT74S1 was recently reported to sequentially glucosylate SECO into SMG and SDG in vitro. However, whether this gene is the only UGT achieving SECO glucosylation in flax was not known. Results Flax genome-wide mining for UGTs was performed. Phylogenetic and gene duplication analyses, heterologous gene expression and enzyme assays were conducted to identify family members closely related to UGT74S1 and to establish their roles in SECO glucosylation. A total of 299 different UGTs were identified, of which 241 (81%) were duplicated. Flax UGTs diverged 2.4–153.6 MYA and 71% were found to be under purifying selection pressure. UGT74S1 , a single copy gene located on chromosome 7, displayed no evidence of duplication and was deemed to be under positive selection pressure. The phylogenetic analysis identified four main clusters where cluster 4, which included UGT74S1 , was the most diverse. The duplicated UGT74S4 and UGT74S3 , located on chromosomes 8 and 14, respectively, were the most closely related to UGT74S1 and were differentially expressed in different tissues. Heterologous expression levels of UGT74S1, UGT74S4 and UGT74S3 proteins were similar but UGT74S4 and UGT74S3 glucosylation activity towards SECO was seven fold less than UGT74S1. In addition, they both failed to produce SDG, suggesting neofunctionalization following their divergence from UGT74S1 . Conclusions We showed that UGT74S1 is closely related to two duplicated genes, UGT74S4 and UGT74S3 which, unlike UGT74S1, failed to glucosylate SMG into SDG. The study suggests that UGT74S1 may be the Key Player in controlling SECO glucosylation into SDG in flax although its closely related genes may also contribute to a minor extent in supplying the SMG precursor to UGT74S1 .
Bourlaye Fofana - One of the best experts on this subject based on the ideXlab platform.
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ugt74s1 is the Key Player in controlling secoisolariciresinol diglucoside sdg formation in flax
BMC Plant Biology, 2017Co-Authors: Bourlaye Fofana, Kaushik Ghose, Jason Mccallum, Sylvie CloutierAbstract:Flax lignan, commonly known as secoisolariciresinol (SECO) diglucoside (SDG), has recently been reported with health-promoting activities, including its positive impact in metabolic diseases. However, not much was reported on the biosynthesis of SDG and its monoglucoside (SMG) until lately. Flax UGT74S1 was recently reported to sequentially glucosylate SECO into SMG and SDG in vitro. However, whether this gene is the only UGT achieving SECO glucosylation in flax was not known. Flax genome-wide mining for UGTs was performed. Phylogenetic and gene duplication analyses, heterologous gene expression and enzyme assays were conducted to identify family members closely related to UGT74S1 and to establish their roles in SECO glucosylation. A total of 299 different UGTs were identified, of which 241 (81%) were duplicated. Flax UGTs diverged 2.4–153.6 MYA and 71% were found to be under purifying selection pressure. UGT74S1, a single copy gene located on chromosome 7, displayed no evidence of duplication and was deemed to be under positive selection pressure. The phylogenetic analysis identified four main clusters where cluster 4, which included UGT74S1, was the most diverse. The duplicated UGT74S4 and UGT74S3, located on chromosomes 8 and 14, respectively, were the most closely related to UGT74S1 and were differentially expressed in different tissues. Heterologous expression levels of UGT74S1, UGT74S4 and UGT74S3 proteins were similar but UGT74S4 and UGT74S3 glucosylation activity towards SECO was seven fold less than UGT74S1. In addition, they both failed to produce SDG, suggesting neofunctionalization following their divergence from UGT74S1. We showed that UGT74S1 is closely related to two duplicated genes, UGT74S4 and UGT74S3 which, unlike UGT74S1, failed to glucosylate SMG into SDG. The study suggests that UGT74S1 may be the Key Player in controlling SECO glucosylation into SDG in flax although its closely related genes may also contribute to a minor extent in supplying the SMG precursor to UGT74S1.
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UGT74S1 is the Key Player in controlling secoisolariciresinol diglucoside (SDG) formation in flax
BMC Plant Biology, 2017Co-Authors: Bourlaye Fofana, Kaushik Ghose, Jason Mccallum, Frank M. You, Sylvie CloutierAbstract:Background Flax lignan, commonly known as secoisolariciresinol (SECO) diglucoside (SDG), has recently been reported with health-promoting activities, including its positive impact in metabolic diseases. However, not much was reported on the biosynthesis of SDG and its monoglucoside (SMG) until lately. Flax UGT74S1 was recently reported to sequentially glucosylate SECO into SMG and SDG in vitro. However, whether this gene is the only UGT achieving SECO glucosylation in flax was not known. Results Flax genome-wide mining for UGTs was performed. Phylogenetic and gene duplication analyses, heterologous gene expression and enzyme assays were conducted to identify family members closely related to UGT74S1 and to establish their roles in SECO glucosylation. A total of 299 different UGTs were identified, of which 241 (81%) were duplicated. Flax UGTs diverged 2.4–153.6 MYA and 71% were found to be under purifying selection pressure. UGT74S1 , a single copy gene located on chromosome 7, displayed no evidence of duplication and was deemed to be under positive selection pressure. The phylogenetic analysis identified four main clusters where cluster 4, which included UGT74S1 , was the most diverse. The duplicated UGT74S4 and UGT74S3 , located on chromosomes 8 and 14, respectively, were the most closely related to UGT74S1 and were differentially expressed in different tissues. Heterologous expression levels of UGT74S1, UGT74S4 and UGT74S3 proteins were similar but UGT74S4 and UGT74S3 glucosylation activity towards SECO was seven fold less than UGT74S1. In addition, they both failed to produce SDG, suggesting neofunctionalization following their divergence from UGT74S1 . Conclusions We showed that UGT74S1 is closely related to two duplicated genes, UGT74S4 and UGT74S3 which, unlike UGT74S1, failed to glucosylate SMG into SDG. The study suggests that UGT74S1 may be the Key Player in controlling SECO glucosylation into SDG in flax although its closely related genes may also contribute to a minor extent in supplying the SMG precursor to UGT74S1 .
Ioannis Kompatsiaris - One of the best experts on this subject based on the ideXlab platform.
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Key Player identification in terrorism related social media networks using centrality measures
European Intelligence and Security Informatics Conference, 2016Co-Authors: Ilias Gialampoukidis, George Kalpakis, Theodora Tsikrika, Stefanos Vrochidis, Ioannis KompatsiarisAbstract:Monitoring terrorist groups and their suspicious activities in social media is a challenging task, given the large amounts of data involved and the need to identify the most influential users in a smart way. To this end, many efforts have focused on using centrality measures for the identification of the Key Players in terrorism-related social media networks, so that their suspension/removal leads to severe disruption in the connectivity of the network. This work proposes a novel centrality measure, Mapping Entropy Betweenness (MEB), and assesses its effectiveness for Key Player identification on a dataset of terrorism-related Twitter user accounts by simulating targeted attacks that remove the most central nodes of the network. The results indicate that the MEB affects the robustness of this terrorist network more than well-established centrality measures.
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EISIC - Key Player Identification in Terrorism-Related Social Media Networks Using Centrality Measures
2016 European Intelligence and Security Informatics Conference (EISIC), 2016Co-Authors: Ilias Gialampoukidis, George Kalpakis, Theodora Tsikrika, Stefanos Vrochidis, Ioannis KompatsiarisAbstract:Monitoring terrorist groups and their suspicious activities in social media is a challenging task, given the large amounts of data involved and the need to identify the most influential users in a smart way. To this end, many efforts have focused on using centrality measures for the identification of the Key Players in terrorism-related social media networks, so that their suspension/removal leads to severe disruption in the connectivity of the network. This work proposes a novel centrality measure, Mapping Entropy Betweenness (MEB), and assesses its effectiveness for Key Player identification on a dataset of terrorism-related Twitter user accounts by simulating targeted attacks that remove the most central nodes of the network. The results indicate that the MEB affects the robustness of this terrorist network more than well-established centrality measures.
