ABSTRACT Graphene, the one-atom-thick sheet of sp2-hybridized carbon atoms, ever since its advent... more ABSTRACT Graphene, the one-atom-thick sheet of sp2-hybridized carbon atoms, ever since its advent in the scientific world, has enjoyed a star status. Owing to its unique structure, graphene is known to have extraordinary physical and chemical properties, such as very high electrical conductivity, exceptionally high surface area, and phenomenal mechanical strength. All these properties make graphene particularly attractive for its application in electrochemical capacitors (ECs), also known as supercapacitors. This chapter focuses on the fundamentals of a capacitor; different types of electrochemical capacitors, including electrochemical double-layer capacitors, pseudocapacitors, asymmetric or “hybrid” capacitors; and the applicability of graphene to each of these supercapacitor classes. One section of this chapter is dedicated to the emerging field of microsupercapacitors and the application of graphene as a material for microsupercapacitors. The chapter concludes with a summary and an outlook for further improvements to the currently existing works.
Two-dimensional graphene is a promising candidate material for use in high-performance enzymatic ... more Two-dimensional graphene is a promising candidate material for use in high-performance enzymatic biofuel cells (EBFCs). In this work, graphene/enzyme has been integrated onto three-dimensional (3D) micropillar arrays in order to obtain efficient enzyme immobilisation and enhanced enzyme loading and facilitate direct electron transfer. The fabrication process of this system combines top-down carbon microelectromechanical systems (C-MEMS) to fabricate the 3D micropillar array platform and bottom-up electrophoretic deposition (EPD) to deposit the graphene/enzyme onto the electrode surface. The amperometric response of the graphene-based bioelectrode exhibited excellent electrochemical activity, which indicated the successful co-deposition of graphene with the enzymes. The developed 3D graphene/enzyme network-based EBFC generated a maximum power density of 136.3 μW cm(-2) at 0.59 V, which is almost seven times the maximum power density of the bare 3D carbon micropillar array-based EBFC.
ABSTRACT Heterogeneous asymmetric hydrogenation of C=O and C=C bonds over chiral molecule-modifie... more ABSTRACT Heterogeneous asymmetric hydrogenation of C=O and C=C bonds over chiral molecule-modified metal particles represents an important route for the production of chiral compounds. In this minireview, we first briefly introduced the background of heterogeneous asymmetric hydrogenation and the remaining challenges in this field. Then, we highlighted recent important progress on the understanding of reaction mechanism in terms of the acid-base properties of supports and the size/shape effects of metal particles. Finally, we summarized the possible models proposed for the substrate-modifier adsorption and their interaction in asymmetric hydrogenation reactions.
Vacuum Microelectronics IEEE International Conference, 1996
To investigate the dependence of emission property of diamond film on the technique used in the f... more To investigate the dependence of emission property of diamond film on the technique used in the film depositions, Field Emitter Arrays (FEAs) with diamond emission surface were manufactured by two different method, with the diamond films being deposited by two techniques. These FEAs were measured, the I-V curves were analyzed, compared and discussed, and some conclusions were given
Enantioselective hydrogenation of isophorone in the presence of (S)-proline was examined over a s... more Enantioselective hydrogenation of isophorone in the presence of (S)-proline was examined over a series of Pd/MgO catalysts with varying Pd particle size. It was found that the Pd surfaces not only supply chemisorbed hydrogen required for the hydrogenation of isophorone but also be involve in the enantiodifferentiating step. Moreover, it was observed for the first time that the configuration of the chiral product could be tuned by varying the size of Pd particle such that (R)-TMCH rather than (S)-TMCH was obtained over the Pd/MgO catalysts with large Pd particles. Two competitive reaction pathways during the enantioselective hydrogenation of isophorone were proposed depending on the size of Pd particle. One involves the enantioselective hydrogenation of the reaction intermediates formed on large Pd particle with size exceeding 10 nm leading to the excess formation of (R)-TMCH enantiomer, whereas the other invokes the primary hydrogenation of isophorone to racemic TMCH over Pd particle with size smaller than 4 nm, followed by the kinetic resolution process leaving the (S)-TMCH enantiomer in excess.
Enantioselective hydrogenation of (Z)--dehydroamino acids on a cinchonidine-modified Pd/Al 2 O 3... more Enantioselective hydrogenation of (Z)--dehydroamino acids on a cinchonidine-modified Pd/Al 2 O 3 catalyst was explored. Comparative studies by using (Z)--dehydroamino acids and esters identified that the carboxylic group in dehydroamino acids was essentially important to get enantioselectivities (33% for aryl substituted and 46% for alkyl substituted -dehydroamino acids). This result extended the range of enantioselective hydrogenation of ␣,-unsaturated carboxylic acids on chirally modified Pd catalysts and offered a new approach to synthesize optically active -amino acids.
Porous Si prepared by the magnesiothermic reaction was used as anode material for lithium ion bat... more Porous Si prepared by the magnesiothermic reaction was used as anode material for lithium ion batteries. The synthesis conditions were investigated to obtain high purity of silicon phase. The structures of porous Si were characterized by TEM, Raman and N 2 adsorption-desorption. The electrochemical performance was tested by cyclic voltammetry (CV) and discharge-charge measurement. The porous Si exhibits larger storage capacity and improved cyclability compared to commercial Si powders. The enhanced capacity and cyclability are attributed to the loose mesoporous structure of porous Si, which can accommodate large volume change in the lithiation/delithiation process.
Belt-shaped molybdenum carbides in α- and β-phases were synthesized by reducing and carburizing a... more Belt-shaped molybdenum carbides in α- and β-phases were synthesized by reducing and carburizing a nano-sized α-MoO3 precursor with hydrocarbon-hydrogen mixtures at appropriate temperatures; the β-Mo2C nanobelts with a higher fraction of coordinatively unsaturated Mo sites were more active than the α-MoC1-x nanobelts in dehydrogenation of benzyl alcohol to benzaldehyde.
ABSTRACT Mo2N nanobelts about 60 nm wide and 0.5-72 mu m long have been synthesized by reacting a... more ABSTRACT Mo2N nanobelts about 60 nm wide and 0.5-72 mu m long have been synthesized by reacting a belt-shaped alpha-MoO3 precursor with ammonia at 850 degrees C. The Mo2N nanobelts effectively and selectively catalyzed dehydrogenation of a variety of aromatic alcohols. The coordinatively unsaturated Mo sites on the surface of the Mo2N nanobelts might be the active species.
The event-related potential technique was used to investigate the time course and scalp-potential... more The event-related potential technique was used to investigate the time course and scalp-potential topography for the numerical distance effect in a number-matching task. Twenty undergraduates judged whether a number matched or did not match another number presented 1.5 s earlier. Compared with number pairs with a 'small' numerical distance (distance=1), number pairs with a 'large' numerical distance (greater than 2) showed a longer latency and a greater positive amplitude in the N240 component. This numerical distance effect was limited to fronto-central electrodes. These results were discussed in terms of the neural bases of the numerical distance effect during the automatic processing of numbers.
Background: Recent molecular genetics studies showed significant associations between dopamine-re... more Background: Recent molecular genetics studies showed significant associations between dopamine-related genes (including genes for dopamine receptors, transporters, and degradation) and working memory, but little is known about the role of genes for dopamine modulation, such as those related to neurotensin (NT), in working memory. A recent animal study has suggested that NT antagonist administration impaired working memory in a learning task. The current study examined associations between NT genes and working memory among humans.
2010 Sixth International Conference on Natural Computation, 2010
ABSTRACT Evolution modeling of complex network is a fruitful field, yet few studies have modeled ... more ABSTRACT Evolution modeling of complex network is a fruitful field, yet few studies have modeled system with spatial information like human brain, and methods for modeling spatial system tend to get inconsistent results. The current study intends to improve it by modeling 3-dimension complex evolution model. With the assumption that probability of having edge depended on distance between nodes, we got a network follows power law.
Traditional behavioral genetic studies (e.g., twin, adoption studies) have shown that human perso... more Traditional behavioral genetic studies (e.g., twin, adoption studies) have shown that human personality has moderate to high heritability, but recent molecular behavioral genetic studies have failed to identify quantitative trait loci (QTL) with consistent effects. The current study adopted a multi-step approach (ANOVA followed by multiple regression and permutation) to assess the cumulative effects of multiple QTLs. Using a system-level (dopamine system) genetic approach, we investigated a personality trait deeply rooted in the nervous system (the Highly Sensitive Personality, HSP). 480 healthy Chinese college students were given the HSP scale and genotyped for 98 representative polymorphisms in all major dopamine neurotransmitter genes. In addition, two environment factors (stressful life events and parental warmth) that have been implicated for their contributions to personality development were included to investigate their relative contributions as compared to genetic factors. In Step 1, using ANOVA, we identified 10 polymorphisms that made statistically significant contributions to HSP. In Step 2, these polymorphism's main effects and interactions were assessed using multiple regression. This model accounted for 15% of the variance of HSP (p,0.001). Recent stressful life events accounted for an additional 2% of the variance. Finally, permutation analyses ascertained the probability of obtaining these findings by chance to be very low, p ranging from 0.001 to 0.006. Dividing these loci by the subsystems of dopamine synthesis, degradation/transport, receptor and modulation, we found that the modulation and receptor subsystems made the most significant contribution to HSP. The results of this study demonstrate the utility of a multi-step neuronal systemlevel approach in assessing genetic contributions to individual differences in human behavior. It can potentially bridge the gap between the high heritability estimates based on traditional behavioral genetics and the lack of reproducible genetic effects observed currently from molecular genetic studies.
International Conference on BioMedical Engineering and Informatics, 2009
This study used the complex network analysis to examine the brain functional network involved in ... more This study used the complex network analysis to examine the brain functional network involved in finger movements. We found that (a) long-range connections decreased exponentially as distance between nodes increased, whereas short-range connections increased linearly with distance; (b) the distribution of functional connections was scale-free; (c) the typical path lengths were relatively short and comparable to those calculated for equivalent random networks, but the clustering coefficients were several orders of magnitude larger than those of equivalent random networks; and (d) central nodes were located in brain regions identified in previous cognitive neuroscience studies. These results suggest that the method of complex network analysis can be an important tool in future research in cognitive neuroscience.
Previous research has shown inconsistent findings regarding the relations between the functional ... more Previous research has shown inconsistent findings regarding the relations between the functional Val158Met polymorphisms of the catechol-O-methyltransferase (COMT) gene and individual differences in personality traits. This study attempts to overcome some of the weaknesses of previous research, namely, small sample sizes, clinical samples, ethnic stratification, wide age ranges, neglecting sex differences, and single measures of personality traits. A large sample (n ¼ 556, 250 male, 306 female) of healthy Chinese college students (mean age ¼ 20.5 ± 1 years) was given a battery of personality scales, including the temperament and character inventory-revised, the behavioral inhibition system and behavioral approach system scale, the Beck depression inventory, and the Beck anxiety inventory. Factor analysis of the affect-related personality traits revealed two factors that corresponded to positive (PEM) and negative emotionality (NEM). We found a consistent COMT-by-sex interaction effect on affect-related personality traits. Compared with males with Met/Met alleles, males with Val/Val alleles showed significantly higher scores on NEM, but lower scores on PEM. Females, however, showed an opposite but nonsignificant pattern. Our results supported the role of the COMT gene in personality traits for males and contributed to the growing literature on sex differences in gene-behavior connections.
Response inhibition refers to the suppression of inappropriate or irrelevant responses. It has a ... more Response inhibition refers to the suppression of inappropriate or irrelevant responses. It has a central role in executive functions, and has been linked to a wide spectrum of prevalent neuropsychiatric disorders. Increasing evidence from neuropharmacological studies has suggested that gene variants in the norepinephrine neurotransmission system make specific contributions to response inhibition. This study genotyped five tag single-nucleotide polymorphisms covering the whole alpha-2B-adrenergic receptor (ADRA2B) gene and investigated their associations with response inhibition in a relatively large healthy Chinese sample (N=421). The results revealed significant genetic effects of the ADRA2B conserved haplotype polymorphisms on response inhibition as measured by stop-signal reaction time (SSRT) (F(2, 418)=5.938, p=0.003). Individuals with the AAGG/AAGG genotype (n=89; mean SSRT=170.2 ms) had significantly shorter SSRTs than did those with either the CCAC/AAGG genotype (n=216; mean SSRT=182.4 ms; uncorrected p=0.03; corrected p=0.09) or the CCAC/CCAC genotype (n=116; mean SSRT=195.8 ms; corrected p<0.002, Cohen's d=0.51). This finding provides the first evidence from association research in support of a critical role of the norepinephrine neurotransmission system in response inhibition. A better understanding of the genetic basis of response inhibition would allow us to develop more effective diagnosis, treatment, and prevention of deficient or underdeveloped response inhibition as well as its related prevalent neuropsychiatric disorders.
This study explored the neural basis of the processing of anomalous information (the N400 e¡ect) ... more This study explored the neural basis of the processing of anomalous information (the N400 e¡ect) in an arithmetic task. Twenty healthy undergraduate students were scanned while they performed a number-matching task. Relative to matched numbers, unmatched numbers elicited signi¢cantly greater activation at left inferior and superior parietal cortex, left inferior frontal gyrus, and left fusiform and lingual gyri. Combining these results and those of previous studies on semantic anomaly, we proposed that the parietal region is the source of the arithmetic N400 component and the left inferior frontal gyrus is involved in domain-general processing of anomalous information. NeuroReport18:747^751
Myosin heavy chain 9, nonmuscle (MYH9) and environmental factors have been shown to be associated... more Myosin heavy chain 9, nonmuscle (MYH9) and environmental factors have been shown to be associated with nonsyndromic cleft lip with or without cleft palate in several populations. Our study aimed to confirm the contribution of MYH9 and environmental factors to nonsyndromic orofacial cleft risk in western Han Chinese. Four single-nucleotide polymorphisms were investigated in 180 case trios and 224 normal peers in western China using transmission disequilibrium test, family-based association test analysis, and logistic regression models. Strong evidence of linkage disequilibrium was found between these markers and the disease by both single-nucleotide polymorphism analysis (G allele at rs2269529 and T allele at rs16996652) and haplotype analysis (G-T [for rs2269529 and rs16996652] and G-A-T [for rs2269529, rs3752462, and rs16996652] among others). Mothers' illness, medication, and passive smoking during the first trimester may increase the risk of nonsyndromic orofacial clefts, but mothers' vitamin (including folic acid) supplementation during the first trimester is a protective factor. Interactions between mothers' passive smoking during the first trimester and T=T genotype of rs16996652 had statistical significance. Risk factors identified in our study may provide a better understanding of the etiological role of MYH9 and influence of environmental factors in nonsyndromic orofacial cleft incidence.
ABSTRACT Graphene, the one-atom-thick sheet of sp2-hybridized carbon atoms, ever since its advent... more ABSTRACT Graphene, the one-atom-thick sheet of sp2-hybridized carbon atoms, ever since its advent in the scientific world, has enjoyed a star status. Owing to its unique structure, graphene is known to have extraordinary physical and chemical properties, such as very high electrical conductivity, exceptionally high surface area, and phenomenal mechanical strength. All these properties make graphene particularly attractive for its application in electrochemical capacitors (ECs), also known as supercapacitors. This chapter focuses on the fundamentals of a capacitor; different types of electrochemical capacitors, including electrochemical double-layer capacitors, pseudocapacitors, asymmetric or “hybrid” capacitors; and the applicability of graphene to each of these supercapacitor classes. One section of this chapter is dedicated to the emerging field of microsupercapacitors and the application of graphene as a material for microsupercapacitors. The chapter concludes with a summary and an outlook for further improvements to the currently existing works.
Two-dimensional graphene is a promising candidate material for use in high-performance enzymatic ... more Two-dimensional graphene is a promising candidate material for use in high-performance enzymatic biofuel cells (EBFCs). In this work, graphene/enzyme has been integrated onto three-dimensional (3D) micropillar arrays in order to obtain efficient enzyme immobilisation and enhanced enzyme loading and facilitate direct electron transfer. The fabrication process of this system combines top-down carbon microelectromechanical systems (C-MEMS) to fabricate the 3D micropillar array platform and bottom-up electrophoretic deposition (EPD) to deposit the graphene/enzyme onto the electrode surface. The amperometric response of the graphene-based bioelectrode exhibited excellent electrochemical activity, which indicated the successful co-deposition of graphene with the enzymes. The developed 3D graphene/enzyme network-based EBFC generated a maximum power density of 136.3 μW cm(-2) at 0.59 V, which is almost seven times the maximum power density of the bare 3D carbon micropillar array-based EBFC.
ABSTRACT Heterogeneous asymmetric hydrogenation of C=O and C=C bonds over chiral molecule-modifie... more ABSTRACT Heterogeneous asymmetric hydrogenation of C=O and C=C bonds over chiral molecule-modified metal particles represents an important route for the production of chiral compounds. In this minireview, we first briefly introduced the background of heterogeneous asymmetric hydrogenation and the remaining challenges in this field. Then, we highlighted recent important progress on the understanding of reaction mechanism in terms of the acid-base properties of supports and the size/shape effects of metal particles. Finally, we summarized the possible models proposed for the substrate-modifier adsorption and their interaction in asymmetric hydrogenation reactions.
Vacuum Microelectronics IEEE International Conference, 1996
To investigate the dependence of emission property of diamond film on the technique used in the f... more To investigate the dependence of emission property of diamond film on the technique used in the film depositions, Field Emitter Arrays (FEAs) with diamond emission surface were manufactured by two different method, with the diamond films being deposited by two techniques. These FEAs were measured, the I-V curves were analyzed, compared and discussed, and some conclusions were given
Enantioselective hydrogenation of isophorone in the presence of (S)-proline was examined over a s... more Enantioselective hydrogenation of isophorone in the presence of (S)-proline was examined over a series of Pd/MgO catalysts with varying Pd particle size. It was found that the Pd surfaces not only supply chemisorbed hydrogen required for the hydrogenation of isophorone but also be involve in the enantiodifferentiating step. Moreover, it was observed for the first time that the configuration of the chiral product could be tuned by varying the size of Pd particle such that (R)-TMCH rather than (S)-TMCH was obtained over the Pd/MgO catalysts with large Pd particles. Two competitive reaction pathways during the enantioselective hydrogenation of isophorone were proposed depending on the size of Pd particle. One involves the enantioselective hydrogenation of the reaction intermediates formed on large Pd particle with size exceeding 10 nm leading to the excess formation of (R)-TMCH enantiomer, whereas the other invokes the primary hydrogenation of isophorone to racemic TMCH over Pd particle with size smaller than 4 nm, followed by the kinetic resolution process leaving the (S)-TMCH enantiomer in excess.
Enantioselective hydrogenation of (Z)--dehydroamino acids on a cinchonidine-modified Pd/Al 2 O 3... more Enantioselective hydrogenation of (Z)--dehydroamino acids on a cinchonidine-modified Pd/Al 2 O 3 catalyst was explored. Comparative studies by using (Z)--dehydroamino acids and esters identified that the carboxylic group in dehydroamino acids was essentially important to get enantioselectivities (33% for aryl substituted and 46% for alkyl substituted -dehydroamino acids). This result extended the range of enantioselective hydrogenation of ␣,-unsaturated carboxylic acids on chirally modified Pd catalysts and offered a new approach to synthesize optically active -amino acids.
Porous Si prepared by the magnesiothermic reaction was used as anode material for lithium ion bat... more Porous Si prepared by the magnesiothermic reaction was used as anode material for lithium ion batteries. The synthesis conditions were investigated to obtain high purity of silicon phase. The structures of porous Si were characterized by TEM, Raman and N 2 adsorption-desorption. The electrochemical performance was tested by cyclic voltammetry (CV) and discharge-charge measurement. The porous Si exhibits larger storage capacity and improved cyclability compared to commercial Si powders. The enhanced capacity and cyclability are attributed to the loose mesoporous structure of porous Si, which can accommodate large volume change in the lithiation/delithiation process.
Belt-shaped molybdenum carbides in α- and β-phases were synthesized by reducing and carburizing a... more Belt-shaped molybdenum carbides in α- and β-phases were synthesized by reducing and carburizing a nano-sized α-MoO3 precursor with hydrocarbon-hydrogen mixtures at appropriate temperatures; the β-Mo2C nanobelts with a higher fraction of coordinatively unsaturated Mo sites were more active than the α-MoC1-x nanobelts in dehydrogenation of benzyl alcohol to benzaldehyde.
ABSTRACT Mo2N nanobelts about 60 nm wide and 0.5-72 mu m long have been synthesized by reacting a... more ABSTRACT Mo2N nanobelts about 60 nm wide and 0.5-72 mu m long have been synthesized by reacting a belt-shaped alpha-MoO3 precursor with ammonia at 850 degrees C. The Mo2N nanobelts effectively and selectively catalyzed dehydrogenation of a variety of aromatic alcohols. The coordinatively unsaturated Mo sites on the surface of the Mo2N nanobelts might be the active species.
The event-related potential technique was used to investigate the time course and scalp-potential... more The event-related potential technique was used to investigate the time course and scalp-potential topography for the numerical distance effect in a number-matching task. Twenty undergraduates judged whether a number matched or did not match another number presented 1.5 s earlier. Compared with number pairs with a 'small' numerical distance (distance=1), number pairs with a 'large' numerical distance (greater than 2) showed a longer latency and a greater positive amplitude in the N240 component. This numerical distance effect was limited to fronto-central electrodes. These results were discussed in terms of the neural bases of the numerical distance effect during the automatic processing of numbers.
Background: Recent molecular genetics studies showed significant associations between dopamine-re... more Background: Recent molecular genetics studies showed significant associations between dopamine-related genes (including genes for dopamine receptors, transporters, and degradation) and working memory, but little is known about the role of genes for dopamine modulation, such as those related to neurotensin (NT), in working memory. A recent animal study has suggested that NT antagonist administration impaired working memory in a learning task. The current study examined associations between NT genes and working memory among humans.
2010 Sixth International Conference on Natural Computation, 2010
ABSTRACT Evolution modeling of complex network is a fruitful field, yet few studies have modeled ... more ABSTRACT Evolution modeling of complex network is a fruitful field, yet few studies have modeled system with spatial information like human brain, and methods for modeling spatial system tend to get inconsistent results. The current study intends to improve it by modeling 3-dimension complex evolution model. With the assumption that probability of having edge depended on distance between nodes, we got a network follows power law.
Traditional behavioral genetic studies (e.g., twin, adoption studies) have shown that human perso... more Traditional behavioral genetic studies (e.g., twin, adoption studies) have shown that human personality has moderate to high heritability, but recent molecular behavioral genetic studies have failed to identify quantitative trait loci (QTL) with consistent effects. The current study adopted a multi-step approach (ANOVA followed by multiple regression and permutation) to assess the cumulative effects of multiple QTLs. Using a system-level (dopamine system) genetic approach, we investigated a personality trait deeply rooted in the nervous system (the Highly Sensitive Personality, HSP). 480 healthy Chinese college students were given the HSP scale and genotyped for 98 representative polymorphisms in all major dopamine neurotransmitter genes. In addition, two environment factors (stressful life events and parental warmth) that have been implicated for their contributions to personality development were included to investigate their relative contributions as compared to genetic factors. In Step 1, using ANOVA, we identified 10 polymorphisms that made statistically significant contributions to HSP. In Step 2, these polymorphism's main effects and interactions were assessed using multiple regression. This model accounted for 15% of the variance of HSP (p,0.001). Recent stressful life events accounted for an additional 2% of the variance. Finally, permutation analyses ascertained the probability of obtaining these findings by chance to be very low, p ranging from 0.001 to 0.006. Dividing these loci by the subsystems of dopamine synthesis, degradation/transport, receptor and modulation, we found that the modulation and receptor subsystems made the most significant contribution to HSP. The results of this study demonstrate the utility of a multi-step neuronal systemlevel approach in assessing genetic contributions to individual differences in human behavior. It can potentially bridge the gap between the high heritability estimates based on traditional behavioral genetics and the lack of reproducible genetic effects observed currently from molecular genetic studies.
International Conference on BioMedical Engineering and Informatics, 2009
This study used the complex network analysis to examine the brain functional network involved in ... more This study used the complex network analysis to examine the brain functional network involved in finger movements. We found that (a) long-range connections decreased exponentially as distance between nodes increased, whereas short-range connections increased linearly with distance; (b) the distribution of functional connections was scale-free; (c) the typical path lengths were relatively short and comparable to those calculated for equivalent random networks, but the clustering coefficients were several orders of magnitude larger than those of equivalent random networks; and (d) central nodes were located in brain regions identified in previous cognitive neuroscience studies. These results suggest that the method of complex network analysis can be an important tool in future research in cognitive neuroscience.
Previous research has shown inconsistent findings regarding the relations between the functional ... more Previous research has shown inconsistent findings regarding the relations between the functional Val158Met polymorphisms of the catechol-O-methyltransferase (COMT) gene and individual differences in personality traits. This study attempts to overcome some of the weaknesses of previous research, namely, small sample sizes, clinical samples, ethnic stratification, wide age ranges, neglecting sex differences, and single measures of personality traits. A large sample (n ¼ 556, 250 male, 306 female) of healthy Chinese college students (mean age ¼ 20.5 ± 1 years) was given a battery of personality scales, including the temperament and character inventory-revised, the behavioral inhibition system and behavioral approach system scale, the Beck depression inventory, and the Beck anxiety inventory. Factor analysis of the affect-related personality traits revealed two factors that corresponded to positive (PEM) and negative emotionality (NEM). We found a consistent COMT-by-sex interaction effect on affect-related personality traits. Compared with males with Met/Met alleles, males with Val/Val alleles showed significantly higher scores on NEM, but lower scores on PEM. Females, however, showed an opposite but nonsignificant pattern. Our results supported the role of the COMT gene in personality traits for males and contributed to the growing literature on sex differences in gene-behavior connections.
Response inhibition refers to the suppression of inappropriate or irrelevant responses. It has a ... more Response inhibition refers to the suppression of inappropriate or irrelevant responses. It has a central role in executive functions, and has been linked to a wide spectrum of prevalent neuropsychiatric disorders. Increasing evidence from neuropharmacological studies has suggested that gene variants in the norepinephrine neurotransmission system make specific contributions to response inhibition. This study genotyped five tag single-nucleotide polymorphisms covering the whole alpha-2B-adrenergic receptor (ADRA2B) gene and investigated their associations with response inhibition in a relatively large healthy Chinese sample (N=421). The results revealed significant genetic effects of the ADRA2B conserved haplotype polymorphisms on response inhibition as measured by stop-signal reaction time (SSRT) (F(2, 418)=5.938, p=0.003). Individuals with the AAGG/AAGG genotype (n=89; mean SSRT=170.2 ms) had significantly shorter SSRTs than did those with either the CCAC/AAGG genotype (n=216; mean SSRT=182.4 ms; uncorrected p=0.03; corrected p=0.09) or the CCAC/CCAC genotype (n=116; mean SSRT=195.8 ms; corrected p<0.002, Cohen's d=0.51). This finding provides the first evidence from association research in support of a critical role of the norepinephrine neurotransmission system in response inhibition. A better understanding of the genetic basis of response inhibition would allow us to develop more effective diagnosis, treatment, and prevention of deficient or underdeveloped response inhibition as well as its related prevalent neuropsychiatric disorders.
This study explored the neural basis of the processing of anomalous information (the N400 e¡ect) ... more This study explored the neural basis of the processing of anomalous information (the N400 e¡ect) in an arithmetic task. Twenty healthy undergraduate students were scanned while they performed a number-matching task. Relative to matched numbers, unmatched numbers elicited signi¢cantly greater activation at left inferior and superior parietal cortex, left inferior frontal gyrus, and left fusiform and lingual gyri. Combining these results and those of previous studies on semantic anomaly, we proposed that the parietal region is the source of the arithmetic N400 component and the left inferior frontal gyrus is involved in domain-general processing of anomalous information. NeuroReport18:747^751
Myosin heavy chain 9, nonmuscle (MYH9) and environmental factors have been shown to be associated... more Myosin heavy chain 9, nonmuscle (MYH9) and environmental factors have been shown to be associated with nonsyndromic cleft lip with or without cleft palate in several populations. Our study aimed to confirm the contribution of MYH9 and environmental factors to nonsyndromic orofacial cleft risk in western Han Chinese. Four single-nucleotide polymorphisms were investigated in 180 case trios and 224 normal peers in western China using transmission disequilibrium test, family-based association test analysis, and logistic regression models. Strong evidence of linkage disequilibrium was found between these markers and the disease by both single-nucleotide polymorphism analysis (G allele at rs2269529 and T allele at rs16996652) and haplotype analysis (G-T [for rs2269529 and rs16996652] and G-A-T [for rs2269529, rs3752462, and rs16996652] among others). Mothers' illness, medication, and passive smoking during the first trimester may increase the risk of nonsyndromic orofacial clefts, but mothers' vitamin (including folic acid) supplementation during the first trimester is a protective factor. Interactions between mothers' passive smoking during the first trimester and T=T genotype of rs16996652 had statistical significance. Risk factors identified in our study may provide a better understanding of the etiological role of MYH9 and influence of environmental factors in nonsyndromic orofacial cleft incidence.
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