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1.
Brain Sci ; 14(5)2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38790422

ABSTRACT

The ability to inhibit conflicting information is pivotal in the dynamic and high-speed context of fast-ball sports. However, the behavioral and electrophysiological characteristics underlying the cognitive inhibition processes associated with table tennis expertise remain unexplored. This study aims to bridge these research gaps by utilizing the color-word Stroop task and the spatial Stroop task alongside event-related potential (ERP) measurements to investigate domain-general and domain-specific cognitive inhibition among table tennis athletes. The study involved a total of 40 participants, including 20 table tennis athletes (11 males and 9 females; mean age 20.75 years) and 20 nonathletes (9 males and 11 females; mean age 19.80 years). The group differences in the Stroop effect on behavioral outcomes and ERP amplitudes were compared within each task, respectively. In the color-word Stroop tasks, athletes exhibited smaller incongruent-related negative potential amplitudes (Ninc; 300-400 ms; p = 0.036) and a diminished Stroop effect on late sustained potential amplitudes (LSP; 500-650 ms; p = 0.028) than nonathletes, although no significant differences were observed in behavioral outcomes (p > 0.05). Conversely, in the spatial Stroop tasks, athletes not only responded more swiftly but also exhibited reduced Stroop effects on both LSP amplitudes (350-500 ms; p = 0.004) and reaction times (p = 0.002) relative to nonathletes. These findings suggest that table tennis athletes excel in cognitive inhibition in the context of both domain-general and domain-specific tasks, particularly exhibiting enhanced performance in tasks that are closely aligned with the demands of their sport. Our results support the neural efficiency hypothesis and improve our understanding of the interactions between cognitive functions and table tennis expertise.

2.
Brain Sci ; 14(3)2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38539611

ABSTRACT

BACKGROUND: Table tennis athletes have been extensively studied for their cognitive processing advantages and brain plasticity. However, limited research has focused on the resting-state function of their brains. This study aims to investigate the network characteristics of the resting-state electroencephalogram in table tennis athletes and identify specific brain network biomarkers. METHODS: A total of 48 healthy right-handed college students participated in this study, including 24 table tennis athletes and 24 controls with no exercise experience. Electroencephalogram data were collected using a 64-conductive active electrode system during eyes-closed resting conditions. The analysis involved examining the average power spectral density and constructing brain functional networks using the weighted phase-lag index. Network topological characteristics were then calculated. RESULTS: The results revealed that table tennis athletes exhibited significantly higher average power spectral density in the α band compared to the control group. Moreover, athletes not only demonstrated stronger functional connections, but they also exhibited enhanced transmission efficiency in the brain network, particularly at the local level. Additionally, a lateralization effect was observed, with more potent interconnected hubs identified in the left hemisphere of the athletes' brain. CONCLUSIONS: Our findings imply that the α band may be uniquely associated with table tennis athletes and their motor skills. The brain network characteristics of athletes during the resting state are worth further attention to gain a better understanding of adaptability of and changes in their brains during training and competition.

3.
Conscious Cogn ; 115: 103570, 2023 10.
Article in English | MEDLINE | ID: mdl-37689042

ABSTRACT

Consciousness is traditionally considered necessary for response inhibition. Recently, researchers have attempted to explore unconscious response inhibition using the masked go/no-go task. However, their findings were controversial and might have been confounded by the methodology employed. Therefore, we used a three-level Bayesian meta-analysis to provide the first systematic overview of the field of unconscious response inhibition. Finally, 34 studies in 16 articles with a total sample size of 521 were included. In summary, we found only inconclusive evidence of a reaction time slowing effect after excluding studies with conscious no-go experience (mean difference = 8.47 ms, BF10 = 2.71). In addition, the overall effect size of the difference in sensitivity to masked stimuli between the masked go/no-go task and the objective awareness task was small and uncertain (mean difference = 0.09, BF10 = 2.39). Taken together, these findings indicate a lack of solid evidence for the occurrence of unconscious response inhibition. Our findings do not oppose the possibility of unconscious response inhibition, but rather emphasize the need for more rigorous research methodologies in this field.


Subject(s)
Consciousness , Unconscious, Psychology , Humans , Bayes Theorem , Consciousness/physiology , Reaction Time/physiology , Inhibition, Psychological
4.
PLoS Biol ; 21(7): e3002197, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37410725

ABSTRACT

Drosophila melanogaster Down syndrome cell adhesion molecule 1 (Dscam1) encodes 19,008 diverse ectodomain isoforms via the alternative splicing of exon 4, 6, and 9 clusters. However, whether individual isoforms or exon clusters have specific significance is unclear. Here, using phenotype-diversity correlation analysis, we reveal the redundant and specific roles of Dscam1 diversity in neuronal wiring. A series of deletion mutations were performed from the endogenous locus harboring exon 4, 6, or 9 clusters, reducing to 396 to 18,612 potential ectodomain isoforms. Of the 3 types of neurons assessed, dendrite self/non-self discrimination required a minimum number of isoforms (approximately 2,000), independent of exon clusters or isoforms. In contrast, normal axon patterning in the mushroom body and mechanosensory neurons requires many more isoforms that tend to associate with specific exon clusters or isoforms. We conclude that the role of the Dscam1 diversity in dendrite self/non-self discrimination is nonspecifically mediated by its isoform diversity. In contrast, a separate role requires variable domain- or isoform-related functions and is essential for other neurodevelopmental contexts, such as axonal growth and branching. Our findings shed new light on a general principle for the role of Dscam1 diversity in neuronal wiring.


Subject(s)
Down Syndrome , Drosophila Proteins , Animals , Drosophila melanogaster/metabolism , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Cell Adhesion Molecule-1/genetics , Cell Adhesion Molecule-1/metabolism , Cell Adhesion Molecules/genetics , Cell Adhesion Molecules/metabolism , Clustered Regularly Interspaced Short Palindromic Repeats , Down Syndrome/genetics , Protein Isoforms/genetics , Protein Isoforms/metabolism , Neurons/metabolism
5.
Environ Sci Pollut Res Int ; 30(26): 68577-68590, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37126162

ABSTRACT

Addressing the impacts of climate change has become a global public crisis and challenge. China is characterized by a complex and diverse topography and vast territory, which makes it worthwhile to explore the differential impacts of climate change on urban electricity consumption in different zones and economic development conditions. This study examines the differential impact of climate factors on urban electricity consumption in China based on monthly panel data for 282 prefectures from 2011 to 2019 and projects the potential demand for future urban electricity consumption under different climate change scenarios. The results show that (1) temperature changes significantly alter urban electricity consumption, with cooling degree days (CDD) and heating degree days (HDD) contributing positively to urban electricity consumption in areas with different regional and economic development statuses, with elasticity coefficients of 0.1015-0.1525 and 0.0029-0.0077, respectively. (2) The temperature-electricity relationship curve shows an irregular U-shape. Each additional day of extreme weather above 30 °C and below -12 °C increases urban electricity consumption by 0.52% and 1.52% in the north and by 2.67% and 1.32% in the south. Poor cities are significantly more sensitive to extremely low temperatures than rich cities. (3) Suppose the impacts of climate degradation on urban electricity consumption are not halted. In that case, the possible Shared Socioeconomic Pathways 1-1.9 (SSP1-1.9), SSP1-2.6, and SSP2-4.5 will increase China's urban electricity consumption by 1621.96 billion kWh, 2960.87 billion kWh, and 6145.65 billion kWh, respectively, by 2090. Finally, this study makes some policy recommendations and expectations for follow-up studies.


Subject(s)
Climate Change , Economic Development , Cities , China , Electricity
6.
PNAS Nexus ; 2(5): pgad135, 2023 May.
Article in English | MEDLINE | ID: mdl-37152679

ABSTRACT

Drosophila Down syndrome cell adhesion molecule 1 (Dscam1) encodes tens of thousands of cell recognition molecules via alternative splicing, which are required for neural function. A canonical self-avoidance model seems to provide a central mechanistic basis for Dscam1 functions in neuronal wiring. Here, we reveal extensive noncanonical functions of Dscam1 isoforms in neuronal wiring. We generated a series of allelic cis mutations in Dscam1, encoding a normal number of isoforms, but with an altered isoform composition. Despite normal dendritic self-avoidance and self-/nonself-discrimination in dendritic arborization (da) neurons, which is consistent with the canonical self-avoidance model, these mutants exhibited strikingly distinct spectra of phenotypic defects in the three types of neurons: up to ∼60% defects in mushroom bodies, a significant increase in branching and growth in da neurons, and mild axonal branching defects in mechanosensory neurons. Remarkably, the altered isoform composition resulted in increased dendrite growth yet inhibited axon growth. Moreover, reducing Dscam1 dosage exacerbated axonal defects in mushroom bodies and mechanosensory neurons but reverted dendritic branching and growth defects in da neurons. This splicing-tuned regulation strategy suggests that axon and dendrite growth in diverse neurons cell-autonomously require Dscam1 isoform composition. These findings provide important insights into the functions of Dscam1 isoforms in neuronal wiring.

7.
Sci Adv ; 8(27): eabn9458, 2022 07 08.
Article in English | MEDLINE | ID: mdl-35857463

ABSTRACT

The Down syndrome cell adhesion molecule 1 (Dscam1) gene can generate tens of thousands of isoforms via alternative splicing, which is essential for nervous and immune functions. Chelicerates generate approximately 50 to 100 shortened Dscam (sDscam) isoforms by alternative promoters, similar to mammalian protocadherins. Here, we reveal that trans-splicing markedly increases the repository of sDscamß isoforms in Tetranychus urticae. Unexpectedly, every variable exon cassette engages in trans-splicing with constant exons from another cluster. Moreover, we provide evidence that competing RNA pairing not only governs alternative cis-splicing but also facilitates trans-splicing. Trans-spliced sDscam isoforms mediate cell adhesion ability but exhibit the same homophilic binding specificity as their cis-spliced counterparts. Thus, we reveal a single sDscam locus that generates diverse adhesion molecules through cis- and trans-splicing coupled with alternative promoters. These findings expand understanding of the mechanism underlying molecular diversity and have implications for the molecular control of neuronal and/or immune specificity.


Subject(s)
Drosophila Proteins , Alternative Splicing , Animals , Drosophila Proteins/genetics , Mammals/genetics , Protein Isoforms/genetics , Protein Isoforms/metabolism , RNA/metabolism , Trans-Splicing
8.
Curr Biol ; 32(13): 2908-2920.e4, 2022 07 11.
Article in English | MEDLINE | ID: mdl-35659864

ABSTRACT

Alternative splicing of Drosophila Dscam1 into 38,016 isoforms provides neurons with a unique molecular code for self-recognition and self-avoidance. A canonical model suggests that the homophilic binding of identical Dscam1 isoforms on the sister branches of mushroom body (MB) axons supports segregation with high fidelity, even when only a single isoform is expressed. Here, we generated a series of mutant flies with a single exon 4, 6, or 9 variant, encoding 1,584, 396, or 576 potential isoforms, respectively. Surprisingly, most of the mutants in the latter two groups exhibited obvious defects in the growth, branching, and segregation of MB axonal sister branches. This demonstrates that the repertoires of 396 and 576 Dscam1 isoforms were not sufficient for the normal patterning of axonal branches. Moreover, reducing Dscam1 levels largely reversed the defects caused by reduced isoform diversity, suggesting a functional link between Dscam1 expression levels and isoform diversity. Taken together, these results indicate that canonical self-avoidance alone does not explain the function of Dscam1 in MB axonal wiring.


Subject(s)
Drosophila Proteins , Mushroom Bodies , Animals , Axons/metabolism , Cell Adhesion Molecules/genetics , Cell Adhesion Molecules/metabolism , Drosophila/genetics , Drosophila/metabolism , Drosophila Proteins/metabolism , Drosophila melanogaster/genetics , Drosophila melanogaster/metabolism , Mushroom Bodies/metabolism , Protein Isoforms/genetics , Protein Isoforms/metabolism
9.
Front Psychol ; 13: 800781, 2022.
Article in English | MEDLINE | ID: mdl-35719555

ABSTRACT

Many reports have emphasized that unconscious processing demands attention. However, some studies were unable to observe a modulation of attentional load in subliminal visual processing. We proposed that the paradoxical phenomena could be explained based on whether the mental workload task was involved in central executive processes. In two experiments, by combining a masked shape discrimination task with an N-back task, executive attention availability for masked visuomotor processing decreased as the N-back task demand increased. We observed that unconscious visuomotor priming diminished with increasing executive attention load in Experiment 2; however, this pattern did not occur in Experiment 1. Further analysis verified that in Experiment 1, the role of the central executive in unconscious visuomotor priming was eliminated by the accuracy-speed trade-off since the higher load spatial N-back tasks with larger memory set sizes, compared with higher load verbal N-bask tasks, were quite difficult for the subjects to manage. Therefore, our results demonstrated that central executive load modulates unconscious visuomotor priming and that this modulation can be weakened by task difficulty. Collectively, by emphasizing the essential role of executive attention in subliminal visuomotor priming, the present work provides a powerful interpretation of prior debates and develops extant attention capacity limitations from the realm of consciousness to that of unconsciousness.

10.
Front Neurosci ; 16: 781099, 2022.
Article in English | MEDLINE | ID: mdl-35401077

ABSTRACT

Unconsciousness is a kind of brain activity that occurs below the level of consciousness, and the masked priming paradigm is a classic paradigm to study unconscious perceptual processing. With the deepening of unconscious perception research, different researchers mostly use different experimental materials and different masked priming paradigms in a single experiment but not for the comprehensive analysis of the unconscious information processing mechanism itself. Thus, the purpose of this study is to conduct a comprehensive analysis through a cross-experimental paradigm, cross-experimental materials, and cross-experimental purposes. We used activation likelihood estimation to test functional magnetic resonance imaging studies, involving 361 subjects, 124 foci in eight studies representing direct comparison of unconscious processing with baseline, and 115 foci in 10 studies representing direct comparison of unconscious priming effects. In the comparison of unconscious processing and baseline, clusters formed in the left superior parietal gyrus, the right insular gyrus, and the right inferior frontal gyrus (IFG) triangular part after correcting for familywise error (FWE). In the comparison of priming effects, clusters formed in only the right IFG triangular part after correcting for FWE. Here, we found that ventral and dorsal pathways jointly regulate unconscious perceptual processes, but only the ventral pathway is involved in the regulation of unconscious priming effects. The IFG triangular part is involved in the regulation of unconscious perceptual processing and unconscious priming effects and may be an important brain area in unconscious information processing. These preliminary data provide conditions for further study of the neural correlation of unconscious information processing.

11.
Sci Adv ; 8(4): eabm1763, 2022 Jan 28.
Article in English | MEDLINE | ID: mdl-35080968

ABSTRACT

Drosophila melanogaster Dscam1 encodes 38,016 isoforms via mutually exclusive splicing; however, the regulatory mechanism behind this is not fully understood. Here, we found a set of hidden RNA secondary structures that balance the stochastic choice of Dscam1 splice variants (designated balancer RNA secondary structures). In vivo mutational analyses revealed the dual function of these balancer interactions in driving the stochastic choice of splice variants, through enhancement of the inclusion of distal exon 6s by cooperating with docking site-selector pairing to form a stronger multidomain pre-mRNA structure and through simultaneous repression of the inclusion of proximal exon 6s by antagonizing their docking site-selector pairings. Thus, we provide an elegant molecular model based on competition and cooperation between two sets of docking site-selector and balancer pairings, which counteracts the "first-come, first-served" principle. Our findings provide conceptual and mechanistic insight into the dynamics and functions of long-range RNA secondary structures.

12.
Front Genet ; 12: 644238, 2021.
Article in English | MEDLINE | ID: mdl-33859670

ABSTRACT

Mutually exclusive splicing is an important mechanism for expanding protein diversity. An extreme example is the Down syndrome cell adhesion molecular (Dscam1) gene of insects, containing four clusters of variable exons (exons 4, 6, 9, and 17), which potentially generates tens of thousands of protein isoforms through mutually exclusive splicing, of which regulatory mechanisms are still elusive. Here, we systematically analyzed the variable exon 4, 6, and 9 clusters of Dscam1 in Coleoptera species. Through comparative genomics and RNA secondary structure prediction, we found apparent evidence that the evolutionarily conserved RNA base pairing mediates mutually exclusive splicing in the Dscam1 exon 4 cluster. In contrast to the fly exon 6, most exon 6 selector sequences in Coleoptera species are partially located in the variable exon region. Besides, bidirectional RNA-RNA interactions are predicted to regulate the mutually exclusive splicing of variable exon 9 of Dscam1. Although the docking sites in exon 4 and 9 clusters are clade specific, the docking sites-selector base pairing is conserved in secondary structure level. In short, our result provided a mechanistic framework for the application of long-range RNA base pairings in regulating the mutually exclusive splicing of Coleoptera Dscam1.

13.
PeerJ ; 9: e10842, 2021.
Article in English | MEDLINE | ID: mdl-33665022

ABSTRACT

This cross-sectional study compared the physical fitness and mental health status of 140 school-age children who participated in sport-specific training with 180 age-matched peers. All the participants were grouped by sport-specific training frequencies in extracurricular time into the following: (i) high sports training frequency group (HFG): training three to five times per week (n = 77, mean [SD] age: 9.60 [0.12] years); (ii) low sports training frequency group (LFG): training once per week (n = 63, mean [SD] age: 9.88 [0.14] years); and (iii) control group (CG): maintaining routine life (n = 180, mean (SD) age: 9.77(0.09) years). Physical fitness status, including body composition (body mass index), endurance (vital capacity; 50 × 8 round trip), speed and agility (50 m sprint), flexibility (sit-and-reach), coordination (1-min rope skipping), and core strength (1-min sit-ups) as well as mental health status was measured. Overall, the results showed that Grade 3 to 4 HFG students showed better total physical fitness scores than the LFG and CG students. Grade 2 and 5 participants in the three groups showed no significant difference in the total physical fitness score. Children in HFG performed better in several PF indicators (i.e., cardiopulmonary function, flexibility, core strength, and coordination) than those in LFG and CG, and children in LFG got a higher score than those in CG on a testing item of 1-min rope skipping. The mental health test results showed that HFG performed better than LFG and CG. The results indicated that participating in sport-specific training 3-5 times per week was beneficial for children's physical and mental health. Additionally, there was a weak and negative correlation between physical fitness and mental health in LFG and CG, while no correlation was found between physical fitness and mental health in HFG.

14.
Biol Sport ; 37(4): 405-413, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33343074

ABSTRACT

During human motor control, the three pathways of motor control coordinate to complete human response and inhibition control, so whether different types of motor skills training will affect the three pathways of motor control is the main question in this study. Magnetic resonance imaging was combined with behavioural evaluation to analyse the effects of different special training sessions on the motor control network of the frontal lobe and basal ganglia and to explore the role of the central nervous system in the regulation of motor behaviour. A Stop-signal paradigm was used to measure reaction and inhibition capacity, functional magnetic resonance imaging was used for whole brain scanning, and resting state data were collected. Compared to the control group, the competitive aerobics athletes had better reflexes while the soccer players had both better reflexes and inhibitory control. Furthermore, we found that training in the two sets of skills resulted in significant differences in different resting state brain function parameters compared with the control group. Additionally, there were significant differences among the three groups in the direct and indirect pathways of motor control in terms of functional connectivity. Open skill training may improve reaction ability while closed skill training improve both reaction and inhibition ability. These results suggest that the strength of the functional connectivity between the right inferior frontal gyrus and the left putamen may be a key to improving the inhibitory, and the left supplementary motor area- bilateral thalamic loop may play an inhibitory role in motor control.

15.
Angew Chem Int Ed Engl ; 59(23): 9088-9093, 2020 Jun 02.
Article in English | MEDLINE | ID: mdl-32162747

ABSTRACT

2D covalent organic frameworks (COFs) are receiving ongoing attention in semiconductor photocatalysis. Herein, we present a photocatalytic selective chemical transformation by combining sp2 carbon-conjugated porphyrin-based covalent organic framework (Por-sp2 c-COF) photocatalysis with TEMPO catalysis illuminated by 623 nm red light-emitting diodes (LEDs). Highly selective conversion of amines into imines was swiftly afforded in minutes. Specifically, the π-conjugation of porphyrin linker leads to extensive absorption of red light; the sp2 -C=C- double bonds linkage ensures the stability of Por-sp2 c-COF under high concentrations of amine. Most importantly, we found that crystalline framework of Por-sp2 c-COF is pivotal for cooperative photocatalysis with (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO). This work foreshadows that the outstanding hallmarks of COFs, particularly crystallinity, could be exploited to address energy and environmental challenges by cooperative photocatalysis.

16.
J Colloid Interface Sci ; 565: 614-622, 2020 Apr 01.
Article in English | MEDLINE | ID: mdl-32032853

ABSTRACT

The selective aerobic oxidation of sulfides is highly attractive for modern organic and pharmaceutical synthesis. Thus, there is an urgent need for exploring new photocatalytic system on this reaction. In this work, we investigated the polyimide-titanium dioxide (Aeroxide P25 TiO2, denoted as P25) photocatalyst in visible light-driven selective aerobic oxidation of sulfides. Polyimide-P25 shows enhanced absorption of visible light. Subsequently, this makes polyimide-P25 exhibits observable photocatalytic activity on visible light-driven selective aerobic oxidation of sulfides while pure polyimide and P25 individually have none. Aided by triethylamine (TEA), the yield of sulfoxide by polyimide-P25 photocatalysis reaches more than 3 folds compared to that without TEA, highlighting the remarkable cooperative effect between polyimide-P25 photocatalysis and TEA catalysis. Moreover, a plausible mechanism is figured out based on the quenching control experiments, kinetic studies and in-situ electron paramagnetic resonance (EPR) tests. This work could provide useful guidance for the rational design of hybrid photocatalysts to undertake challenging selective chemical transformations.

17.
Angew Chem Int Ed Engl ; 59(9): 3624-3629, 2020 Feb 24.
Article in English | MEDLINE | ID: mdl-31773844

ABSTRACT

The construction of 2D and 3D covalent organic frameworks (COFs) from functional moieties for desired properties has gained much attention. However, the influence of COFs dimensionality on their functionalities, which can further assist in COF design, has never been explored. Now, by selecting designed precursors and topology diagrams, 2D and 3D porphyrinic COFs (2D-PdPor-COF and 3D-PdPor-COF) are synthesized. By model building and Rietveld refinement of powder X-ray diffraction, 2D-PdPor-COF crystallizes as 2D sheets while 3D-PdPor-COF adopts a five-fold interpenetrated pts topology. Interestingly, compared with 2D-PdPor-COF, 3D-PdPor-COF showed interesting properties, including 1) higher CO2 adsorption capacity; 2) better photocatalytic performance; and 3) size-selective photocatalysis. Based on this study, we believe that with the incorporation of functional moieties, the dimensionality of COFs can definitely influence their functionalities.

18.
Angew Chem Int Ed Engl ; 58(19): 6430-6434, 2019 May 06.
Article in English | MEDLINE | ID: mdl-30884054

ABSTRACT

The construction of stable covalent organic frameworks (COFs) for various applications is highly desirable. Herein, we report the synthesis of a novel two-dimensional (2D) porphyrin-based sp2 carbon-conjugated COF (Por-sp2 c-COF), which adopts an eclipsed AA stacking structure with a Brunauer-Emmett-Teller surface area of 689 m2 g-1 . Owing to the C=C linkages, Por-sp2 c-COF shows a high chemical stability under various conditions, even under harsh conditions such as 9 m HCl and 9 m NaOH solutions. Interestingly, Por-sp2 c-COF can be used as a metal-free heterogeneous photocatalyst for the visible-light-induced aerobic oxidation of amines to imines. More importantly, in comparison to imine-linked Por-COF, the inherent structure of Por-sp2 c-COF equips it with several advantages as a photocatalyst, including reusability and high photocatalytic performance. This clearly demonstrates that sp2 carbon-linked 2D COFs can provide an interesting platform for heterogeneous photocatalysis.

19.
J Org Chem ; 81(19): 9296-9307, 2016 10 07.
Article in English | MEDLINE | ID: mdl-27654104

ABSTRACT

The facile one-step reaction of [60]fullerene with aldehydes and primary amines in the presence of cheap and easily available Cu(OAc)2·H2O afforded a series of new types of fulleropyrrolines with trisubstituted C═C bonds in good to excellent yields, which would be difficult to prepare by known methods. The formed fulleropyrroline under the assistance of Pd(OAc)2 and CuCl2·2H2O could be further converted to 1-fulleropyrrolidine by the chlorohydroxylation reaction of C═C bond. Subsequent elimination reaction of 1-fulleropyrrolidine with the aid of TsOH·H2O generated the scarce 1-fulleropyrroline derivative.

20.
J Nanosci Nanotechnol ; 16(4): 3457-67, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27451650

ABSTRACT

Chemical derived graphene oxide, an atomically thin sheet of graphite with two-dimensional construction, offers interesting physical, electronic, thermal, chemical, and mechanical properties that are currently being explored for advanced physics electronics, membranes, and composites. Herein, we study graphene quantum dots (GQD) with the blue photoluminescence under various parameters. The GQD samples were prepared at different temperatures, and the blue photoluminescence intensity of the solution improved radically as the heating temperatures increased. Concerning PL peak and intensity of the quantum dots, the results demonstrated dependence on time under heating, temperature of heating, and pH adjusted by the addition of sodium hydroxide. After hydrothermal synthesis routes, the functional groups of graphene oxide were altered the morphology showed the stacking configuration, and self-assembled structure of the graphene sheets with obvious wrinkles appeared at the edge structures. In addition, absorption, PL, and PLE spectra of the graphene quantum dots increase with different quantities of sodium hydroxide added. Finally, using GQD to target PNTIA cells was carried out successfully. High uptake efficiency and no cytotoxic effects indicate graphene quantum dots can be suitable for bio-targeting.


Subject(s)
Graphite/chemistry , Luminescent Measurements/methods , Nanoparticles/chemistry , Prostate/cytology , Quantum Dots , Cell Line , Cell Survival/drug effects , Crystallization/methods , Graphite/toxicity , Humans , Male , Materials Testing , Nanoparticles/toxicity , Nanoparticles/ultrastructure , Particle Size , Prostate/chemistry , Prostate/drug effects
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