ABSTRACT A player׳s knowledge of her own actions and the corresponding payoffs may enable her to ... more ABSTRACT A player׳s knowledge of her own actions and the corresponding payoffs may enable her to infer or form beliefs about what the payoffs would have been if she had played differently. For quantitative learning models employed in studies of low information environments, players׳ ex-post inferences and beliefs have been largely ignored. For games with large strategy spaces, this omission can seriously weaken the predictive power of a learning model. We propose a novel method of using players׳ ex-post inferences and assessments to impute foregone payoffs for unplayed strategies in low-information environments. We then use the resulting learning model to explain the pricing and learning behavior observed in a Bertrand market experiment. Maximum likelihood estimation shows that the extended model organizes the data remarkably well at both the aggregate and individual levels.
Acetaminophen (APAP) is used drugs worldwide for treating pain and fever. However, APAP overdose ... more Acetaminophen (APAP) is used drugs worldwide for treating pain and fever. However, APAP overdose is the principal cause of acute liver failure in Western countries. Salvianolic acid B (SalB), a major water-soluble compound extracted from Radix Salvia miltiorrhiza, has well-known antioxidant and anti-inflammatory actions. We aimed to evaluate the ability of SalB to protect against APAP-induced acute hepatotoxicity by inducing nuclear factor-erythroid-2-related factor 2 (Nrf2) expression. SalB pretreatment ameliorated acute liver injury caused by APAP, as indicated by blood aspartate transaminase levels and histological findings. Moreover, SalB pretreatment increased the expression of Nrf2, Heme oxygenase-1 (HO-1) and glutamate-l-cysteine ligase catalytic subunit (GCLC). Furthermore, the HO-1 inhibitor zinc protoporphyrin and the GCLC inhibitor buthionine sulfoximine reversed the protective effect of SalB. Additionally, siRNA-mediated depletion of Nrf2 reduced the induction of HO-1 and GCLC by SalB, and SalB pretreatment activated the phosphatidylinositol-3-kinase (PI3K) and protein kinase C (PKC) signaling pathways. Both inhibitors (PI3K and PKC) blocked the protective effect of SalB against APAP-induced cell death, abolishing the SalB-induced Nrf2 activation and decreasing HO-1 and GCLC expression. These results indicated that SalB induces Nrf2, HO-1 and GCLC expression via activation of the PI3K and PKC pathways, thereby protecting against APAP-induced liver injury.
Applied microbiology and biotechnology, Jan 10, 2015
Glycosyltransferase DesVII and its auxiliary partner DesVIII from Streptomyces venezulae, homolog... more Glycosyltransferase DesVII and its auxiliary partner DesVIII from Streptomyces venezulae, homologs of EryCIII and EryCII in Saccharopolyspora erythraea, have previously been demonstrated to be flexible on their substrates in vitro. Herein, we investigated their in vivo function by interspecies complementation in the mutant strains of Sac. erythraea A226. As desVII and desVIII were concomitantly expressed in the ΔeryCIII mutant, the erythromycin A (Er-A) production was restored. Interestingly, co-expression of desVII and desVIII in the ΔeryBV mutant exhibited an increased Er-A yield by 15 % in comparison to A226. Hence, DesVII/DesVIII not only replaced EryCIII to upload D-desosamine to C5 position of 3-O-mycarosyl erythronolide B (MEB) but also in vivo attached L-mycarose, not D-desosamine to C3 position of erythronolide B (EB) with a higher activity than EryBV. Furthermore, expression of desVII in ΔeryCIII and ΔeryBV-CIII partially restored the Er-A production; however, no Er-A was ...
BldD (SACE_2077), a key developmental regulator in actinomycetes, is the first identified transcr... more BldD (SACE_2077), a key developmental regulator in actinomycetes, is the first identified transcriptional factor in Saccharopolyspora erythraea positively regulating erythromycin production and morphological differentiation. Although the BldD of S. erythraea binds to the promoters of erythromycin biosynthetic genes, the interaction affinities are relatively low, implying the existence of its other target genes in S. erythraea. Through the genomic systematic evolution of ligands by exponential enrichment (SELEX) method that we herein improved, four DNA sequences of S. erythraea A226, corresponding to the promoter regions of SACE_0306 (beta-galactosidase), SACE_0811 (50S ribosomal protein L25), SACE_3410 (fumarylacetoacetate hydrolase), and SACE_6014 (aldehyde dehydrogenase), were captured with all three BldD concentrations of 0.5, 1, and 2 μM, while the previously identified intergenic regions of eryBIV-eryAI and ermE-eryCI plus the promoter region of SACE_7115, the amfC homolog for ...
In the case of polymer blending, specific interaction between components is essential to form a m... more In the case of polymer blending, specific interaction between components is essential to form a miscible system. For PHB and PHBV, the carbonyl groups in their chains are available to form hydrogen bonds (H-bonds) with hydroxyl and amino groups. Such H-bonding may lead to ...
Journal of Industrial Microbiology & Biotechnology, 2014
Erythromycin, a medically important antibiotic, is produced by Saccharopolyspora erythraea. Unusu... more Erythromycin, a medically important antibiotic, is produced by Saccharopolyspora erythraea. Unusually, the erythromycin biosynthetic gene cluster lacks a regulatory gene, and the regulation of its biosynthesis remains largely unknown. In this study, through gene deletion, complementation and overexpression experiments, we identified a novel TetR family transcriptional regulator SACE_3986 negatively regulating erythromycin biosynthesis in S. erythraea A226. When SACE_3986 was further inactivated in an industrial strain WB, erythromycin A yield of the mutant was increased by 54.2 % in average compared with that of its parent strain, displaying the universality of SACE_3986 as a repressor for erythromycin production in S. erythraea. qRT-PCR analysis indicated that SACE_3986 repressed the transcription of its adjacent gene SACE_3985 (which encodes a short-chain dehydrogenase/reductase), erythromycin biosynthetic gene eryAI and the resistance gene ermE. As determined by EMSA analysis, purified SACE_3986 protein specifically bound to the intergenic region between SACE_3985 and SACE_3986, whereas it did not bind to the promoter regions of eryAI and ermE. Furthermore, overexpression of SACE_3985 in A226 led to enhanced erythromycin A yield by at least 32.6 %. These findings indicate that SACE_3986 is a negative regulator of erythromycin biosynthesis, and the adjacent gene SACE_3985 is one of its target genes. The present study provides a basis to increase erythromycin production by engineering of SACE_3986 and SACE_3985 in S. erythraea.
... Actuat. B 139(2009) 317-321. [8] S. Nazarpour, CL pez-G ndara, C. Zamani, JM Fern ndez-Sanju ... more ... Actuat. B 139(2009) 317-321. [8] S. Nazarpour, CL pez-G ndara, C. Zamani, JM Fern ndez-Sanju n, FM Ramos, A. Cirera, J. Alloys Compd. 505 (2010) 534-541. ... 43 (2000) 567-571. [35]I. Manna, PP Chattopadhyay, F. Banhart, HD Fecht, Appl. Phys. Lett. 81 (2002) 4136-4138. ...
FTIR spectroscopy was used to verify the presence of intermolecular hydrogen bond (inter-H-bond) ... more FTIR spectroscopy was used to verify the presence of intermolecular hydrogen bond (inter-H-bond) between poly(3-hydroxybutyrate co-3-hydroxyvalerate) (PHBV) and bisphenol A (BPA). By monitoring the spectral changes during PHBV crystallization and blends ...
Streptomyces hygroscopicus 5008 has been used for the production of the antifungal validamycin/ji... more Streptomyces hygroscopicus 5008 has been used for the production of the antifungal validamycin/jinggangmycin for more than 40 years. A high yield of validamycin is achieved by culturing the strain at 37°C, rather than at 30°C for normal growth and sporulation. The mechanism(s) of its thermo-regulated biosynthesis was largely unknown. The 10,383,684-bp genome of strain 5008 was completely sequenced and composed of a linear chromosome, a 164.57-kb linear plasmid, and a 73.28-kb circular plasmid. Compared with other Streptomyces genomes, the chromosome of strain 5008 has a smaller core region and shorter terminal inverted repeats, encodes more α/β hydrolases, major facilitator superfamily transporters, and Mg2+/Mn2+-dependent regulatory phosphatases. Transcriptomic analysis revealed that the expression of 7.5% of coding sequences was increased at 37°C, including biosynthetic genes for validamycin and other three secondary metabolites. At 37°C, a glutamate dehydrogenase was transcriptionally up-regulated, and further proved its involvement in validamycin production by gene replacement. Moreover, efficient synthesis and utilization of intracellular glutamate were noticed in strain 5008 at 37°C, revealing glutamate as the nitrogen source for validamycin biosynthesis. Furthermore, a SARP-family regulatory gene with enhanced transcription at 37°C was identified and confirmed to be positively involved in the thermo-regulation of validamycin production by gene inactivation and transcriptional analysis. Strain 5008 seemed to have evolved with specific genomic components to facilitate the thermo-regulated validamycin biosynthesis. The data obtained here will facilitate future studies for validamycin yield improvement and industrial bioprocess optimization.
The light-bulb idea metaphor (a light bulb above
someone’s head that appears or switches on when ... more The light-bulb idea metaphor (a light bulb above someone’s head that appears or switches on when they think of an idea) is widespread in the literature and popular culture. But, to the best of our knowledge, nobody has ever built an actual device that implements this function. The “Inventometer” is a fun and playful wearable device that measures and displays epiphanometric data to a real light bulb, so its wearer and others in the environment are alerted to “aha! moments” (“eureka moments”), epiphanies, inventions, and idea formation in the brain/mind of the wearer. It senses brainwave signals indicative of epiphanies, and indicates to others a continuously varying epiphanometric quantity by adjusting the light output of the bulb. It uses simple machine learning on EEG (electroencephalogaph) brainwave signals to automatically detect and quantify the novelty of ideas formed in the brain. Long exposure photographs — made while one or more Inventometer wearers walk around a room — result in a Phenomenal Augmented Reality (Augmented Reality of or pertaining to physical phenomena and phenomenology). In particular, these “epiphanographs”, over time, indicate what sorts of things in an environment tended to stimulate epiphanies and to what degree — epiphanogrammetry as a possible new field of study. Brain Games are designed so multiple people can compete using their minds much like people competing using their bodies (e.g. arm wrestling). The “brightest” people in a room become visible by way of their epiphanographs. But with their wearable display bulbs glowing brightly, they also serve as a distraction to each other, thus introducing a richly complex and competitive collective biofeedback gaming space. The device is meant to appeal to people of all ages, from children to university students, and thus forms a good teaching for making skills, science, and engineering (e.g. power electronics, 3D printing, etc.). It is also an ongoing research project
ABSTRACT A player׳s knowledge of her own actions and the corresponding payoffs may enable her to ... more ABSTRACT A player׳s knowledge of her own actions and the corresponding payoffs may enable her to infer or form beliefs about what the payoffs would have been if she had played differently. For quantitative learning models employed in studies of low information environments, players׳ ex-post inferences and beliefs have been largely ignored. For games with large strategy spaces, this omission can seriously weaken the predictive power of a learning model. We propose a novel method of using players׳ ex-post inferences and assessments to impute foregone payoffs for unplayed strategies in low-information environments. We then use the resulting learning model to explain the pricing and learning behavior observed in a Bertrand market experiment. Maximum likelihood estimation shows that the extended model organizes the data remarkably well at both the aggregate and individual levels.
Acetaminophen (APAP) is used drugs worldwide for treating pain and fever. However, APAP overdose ... more Acetaminophen (APAP) is used drugs worldwide for treating pain and fever. However, APAP overdose is the principal cause of acute liver failure in Western countries. Salvianolic acid B (SalB), a major water-soluble compound extracted from Radix Salvia miltiorrhiza, has well-known antioxidant and anti-inflammatory actions. We aimed to evaluate the ability of SalB to protect against APAP-induced acute hepatotoxicity by inducing nuclear factor-erythroid-2-related factor 2 (Nrf2) expression. SalB pretreatment ameliorated acute liver injury caused by APAP, as indicated by blood aspartate transaminase levels and histological findings. Moreover, SalB pretreatment increased the expression of Nrf2, Heme oxygenase-1 (HO-1) and glutamate-l-cysteine ligase catalytic subunit (GCLC). Furthermore, the HO-1 inhibitor zinc protoporphyrin and the GCLC inhibitor buthionine sulfoximine reversed the protective effect of SalB. Additionally, siRNA-mediated depletion of Nrf2 reduced the induction of HO-1 and GCLC by SalB, and SalB pretreatment activated the phosphatidylinositol-3-kinase (PI3K) and protein kinase C (PKC) signaling pathways. Both inhibitors (PI3K and PKC) blocked the protective effect of SalB against APAP-induced cell death, abolishing the SalB-induced Nrf2 activation and decreasing HO-1 and GCLC expression. These results indicated that SalB induces Nrf2, HO-1 and GCLC expression via activation of the PI3K and PKC pathways, thereby protecting against APAP-induced liver injury.
Applied microbiology and biotechnology, Jan 10, 2015
Glycosyltransferase DesVII and its auxiliary partner DesVIII from Streptomyces venezulae, homolog... more Glycosyltransferase DesVII and its auxiliary partner DesVIII from Streptomyces venezulae, homologs of EryCIII and EryCII in Saccharopolyspora erythraea, have previously been demonstrated to be flexible on their substrates in vitro. Herein, we investigated their in vivo function by interspecies complementation in the mutant strains of Sac. erythraea A226. As desVII and desVIII were concomitantly expressed in the ΔeryCIII mutant, the erythromycin A (Er-A) production was restored. Interestingly, co-expression of desVII and desVIII in the ΔeryBV mutant exhibited an increased Er-A yield by 15 % in comparison to A226. Hence, DesVII/DesVIII not only replaced EryCIII to upload D-desosamine to C5 position of 3-O-mycarosyl erythronolide B (MEB) but also in vivo attached L-mycarose, not D-desosamine to C3 position of erythronolide B (EB) with a higher activity than EryBV. Furthermore, expression of desVII in ΔeryCIII and ΔeryBV-CIII partially restored the Er-A production; however, no Er-A was ...
BldD (SACE_2077), a key developmental regulator in actinomycetes, is the first identified transcr... more BldD (SACE_2077), a key developmental regulator in actinomycetes, is the first identified transcriptional factor in Saccharopolyspora erythraea positively regulating erythromycin production and morphological differentiation. Although the BldD of S. erythraea binds to the promoters of erythromycin biosynthetic genes, the interaction affinities are relatively low, implying the existence of its other target genes in S. erythraea. Through the genomic systematic evolution of ligands by exponential enrichment (SELEX) method that we herein improved, four DNA sequences of S. erythraea A226, corresponding to the promoter regions of SACE_0306 (beta-galactosidase), SACE_0811 (50S ribosomal protein L25), SACE_3410 (fumarylacetoacetate hydrolase), and SACE_6014 (aldehyde dehydrogenase), were captured with all three BldD concentrations of 0.5, 1, and 2 μM, while the previously identified intergenic regions of eryBIV-eryAI and ermE-eryCI plus the promoter region of SACE_7115, the amfC homolog for ...
In the case of polymer blending, specific interaction between components is essential to form a m... more In the case of polymer blending, specific interaction between components is essential to form a miscible system. For PHB and PHBV, the carbonyl groups in their chains are available to form hydrogen bonds (H-bonds) with hydroxyl and amino groups. Such H-bonding may lead to ...
Journal of Industrial Microbiology & Biotechnology, 2014
Erythromycin, a medically important antibiotic, is produced by Saccharopolyspora erythraea. Unusu... more Erythromycin, a medically important antibiotic, is produced by Saccharopolyspora erythraea. Unusually, the erythromycin biosynthetic gene cluster lacks a regulatory gene, and the regulation of its biosynthesis remains largely unknown. In this study, through gene deletion, complementation and overexpression experiments, we identified a novel TetR family transcriptional regulator SACE_3986 negatively regulating erythromycin biosynthesis in S. erythraea A226. When SACE_3986 was further inactivated in an industrial strain WB, erythromycin A yield of the mutant was increased by 54.2 % in average compared with that of its parent strain, displaying the universality of SACE_3986 as a repressor for erythromycin production in S. erythraea. qRT-PCR analysis indicated that SACE_3986 repressed the transcription of its adjacent gene SACE_3985 (which encodes a short-chain dehydrogenase/reductase), erythromycin biosynthetic gene eryAI and the resistance gene ermE. As determined by EMSA analysis, purified SACE_3986 protein specifically bound to the intergenic region between SACE_3985 and SACE_3986, whereas it did not bind to the promoter regions of eryAI and ermE. Furthermore, overexpression of SACE_3985 in A226 led to enhanced erythromycin A yield by at least 32.6 %. These findings indicate that SACE_3986 is a negative regulator of erythromycin biosynthesis, and the adjacent gene SACE_3985 is one of its target genes. The present study provides a basis to increase erythromycin production by engineering of SACE_3986 and SACE_3985 in S. erythraea.
... Actuat. B 139(2009) 317-321. [8] S. Nazarpour, CL pez-G ndara, C. Zamani, JM Fern ndez-Sanju ... more ... Actuat. B 139(2009) 317-321. [8] S. Nazarpour, CL pez-G ndara, C. Zamani, JM Fern ndez-Sanju n, FM Ramos, A. Cirera, J. Alloys Compd. 505 (2010) 534-541. ... 43 (2000) 567-571. [35]I. Manna, PP Chattopadhyay, F. Banhart, HD Fecht, Appl. Phys. Lett. 81 (2002) 4136-4138. ...
FTIR spectroscopy was used to verify the presence of intermolecular hydrogen bond (inter-H-bond) ... more FTIR spectroscopy was used to verify the presence of intermolecular hydrogen bond (inter-H-bond) between poly(3-hydroxybutyrate co-3-hydroxyvalerate) (PHBV) and bisphenol A (BPA). By monitoring the spectral changes during PHBV crystallization and blends ...
Streptomyces hygroscopicus 5008 has been used for the production of the antifungal validamycin/ji... more Streptomyces hygroscopicus 5008 has been used for the production of the antifungal validamycin/jinggangmycin for more than 40 years. A high yield of validamycin is achieved by culturing the strain at 37°C, rather than at 30°C for normal growth and sporulation. The mechanism(s) of its thermo-regulated biosynthesis was largely unknown. The 10,383,684-bp genome of strain 5008 was completely sequenced and composed of a linear chromosome, a 164.57-kb linear plasmid, and a 73.28-kb circular plasmid. Compared with other Streptomyces genomes, the chromosome of strain 5008 has a smaller core region and shorter terminal inverted repeats, encodes more α/β hydrolases, major facilitator superfamily transporters, and Mg2+/Mn2+-dependent regulatory phosphatases. Transcriptomic analysis revealed that the expression of 7.5% of coding sequences was increased at 37°C, including biosynthetic genes for validamycin and other three secondary metabolites. At 37°C, a glutamate dehydrogenase was transcriptionally up-regulated, and further proved its involvement in validamycin production by gene replacement. Moreover, efficient synthesis and utilization of intracellular glutamate were noticed in strain 5008 at 37°C, revealing glutamate as the nitrogen source for validamycin biosynthesis. Furthermore, a SARP-family regulatory gene with enhanced transcription at 37°C was identified and confirmed to be positively involved in the thermo-regulation of validamycin production by gene inactivation and transcriptional analysis. Strain 5008 seemed to have evolved with specific genomic components to facilitate the thermo-regulated validamycin biosynthesis. The data obtained here will facilitate future studies for validamycin yield improvement and industrial bioprocess optimization.
The light-bulb idea metaphor (a light bulb above
someone’s head that appears or switches on when ... more The light-bulb idea metaphor (a light bulb above someone’s head that appears or switches on when they think of an idea) is widespread in the literature and popular culture. But, to the best of our knowledge, nobody has ever built an actual device that implements this function. The “Inventometer” is a fun and playful wearable device that measures and displays epiphanometric data to a real light bulb, so its wearer and others in the environment are alerted to “aha! moments” (“eureka moments”), epiphanies, inventions, and idea formation in the brain/mind of the wearer. It senses brainwave signals indicative of epiphanies, and indicates to others a continuously varying epiphanometric quantity by adjusting the light output of the bulb. It uses simple machine learning on EEG (electroencephalogaph) brainwave signals to automatically detect and quantify the novelty of ideas formed in the brain. Long exposure photographs — made while one or more Inventometer wearers walk around a room — result in a Phenomenal Augmented Reality (Augmented Reality of or pertaining to physical phenomena and phenomenology). In particular, these “epiphanographs”, over time, indicate what sorts of things in an environment tended to stimulate epiphanies and to what degree — epiphanogrammetry as a possible new field of study. Brain Games are designed so multiple people can compete using their minds much like people competing using their bodies (e.g. arm wrestling). The “brightest” people in a room become visible by way of their epiphanographs. But with their wearable display bulbs glowing brightly, they also serve as a distraction to each other, thus introducing a richly complex and competitive collective biofeedback gaming space. The device is meant to appeal to people of all ages, from children to university students, and thus forms a good teaching for making skills, science, and engineering (e.g. power electronics, 3D printing, etc.). It is also an ongoing research project
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Papers by Hang Wu
someone’s head that appears or switches on when they think of an
idea) is widespread in the literature and popular culture. But, to
the best of our knowledge, nobody has ever built an actual device
that implements this function. The “Inventometer” is a fun and
playful wearable device that measures and displays epiphanometric
data to a real light bulb, so its wearer and others in the
environment are alerted to “aha! moments” (“eureka moments”),
epiphanies, inventions, and idea formation in the brain/mind of
the wearer. It senses brainwave signals indicative of epiphanies,
and indicates to others a continuously varying epiphanometric
quantity by adjusting the light output of the bulb. It uses simple
machine learning on EEG (electroencephalogaph) brainwave
signals to automatically detect and quantify the novelty of ideas
formed in the brain. Long exposure photographs — made while
one or more Inventometer wearers walk around a room —
result in a Phenomenal Augmented Reality (Augmented Reality
of or pertaining to physical phenomena and phenomenology). In
particular, these “epiphanographs”, over time, indicate what sorts
of things in an environment tended to stimulate epiphanies and
to what degree — epiphanogrammetry as a possible new field of
study. Brain Games are designed so multiple people can compete
using their minds much like people competing using their bodies
(e.g. arm wrestling). The “brightest” people in a room become
visible by way of their epiphanographs. But with their wearable
display bulbs glowing brightly, they also serve as a distraction to
each other, thus introducing a richly complex and competitive
collective biofeedback gaming space. The device is meant to
appeal to people of all ages, from children to university students,
and thus forms a good teaching for making skills, science, and
engineering (e.g. power electronics, 3D printing, etc.). It is also
an ongoing research project
someone’s head that appears or switches on when they think of an
idea) is widespread in the literature and popular culture. But, to
the best of our knowledge, nobody has ever built an actual device
that implements this function. The “Inventometer” is a fun and
playful wearable device that measures and displays epiphanometric
data to a real light bulb, so its wearer and others in the
environment are alerted to “aha! moments” (“eureka moments”),
epiphanies, inventions, and idea formation in the brain/mind of
the wearer. It senses brainwave signals indicative of epiphanies,
and indicates to others a continuously varying epiphanometric
quantity by adjusting the light output of the bulb. It uses simple
machine learning on EEG (electroencephalogaph) brainwave
signals to automatically detect and quantify the novelty of ideas
formed in the brain. Long exposure photographs — made while
one or more Inventometer wearers walk around a room —
result in a Phenomenal Augmented Reality (Augmented Reality
of or pertaining to physical phenomena and phenomenology). In
particular, these “epiphanographs”, over time, indicate what sorts
of things in an environment tended to stimulate epiphanies and
to what degree — epiphanogrammetry as a possible new field of
study. Brain Games are designed so multiple people can compete
using their minds much like people competing using their bodies
(e.g. arm wrestling). The “brightest” people in a room become
visible by way of their epiphanographs. But with their wearable
display bulbs glowing brightly, they also serve as a distraction to
each other, thus introducing a richly complex and competitive
collective biofeedback gaming space. The device is meant to
appeal to people of all ages, from children to university students,
and thus forms a good teaching for making skills, science, and
engineering (e.g. power electronics, 3D printing, etc.). It is also
an ongoing research project