The human brain develops rapidly in the first postnatal year, in which rewired functional brain networks could shape later behavioral and cognitive performance. Resting-state functional magnetic ...resonances imaging (rs-fMRI) and complex network analysis have been widely used for characterizing the developmental brain functional connectome. Yet, such studies focusing on the first year of postnatal life are still very limited. Leveraging normally developing longitudinal infant rs-fMRI scans from neonate to one year of age, we investigated how brain functional networks develop at a fine temporal scale (every 3 months). Considering challenges in the infant fMRI-based network analysis, we developed a novel algorithm to construct the robust, temporally consistent and modular structure augmented group-level network based on which functional modules were detected at each age. Our study reveals that the brain functional network is gradually subdivided into an increasing number of functional modules accompanied by the strengthened intra- and inter-modular connectivities. Based on the developing modules, we found connector hubs (the high-centrality regions connecting different modules) emerging and increasing, while provincial hubs (the high-centrality regions connecting regions in the same module) diminishing. Further region-wise longitudinal analysis validates that different hubs have distinct developmental trajectories of the intra- and inter-modular connections suggesting different types of role transitions in network, such as non-hubs to hubs or provincial hubs to connector hubs et al. All findings indicate that functional segregation and integration are both increased in the first year of postnatal life. The module reorganization and hub transition lead to more efficient brain networks, featuring increasingly segregated modular structure and more connector hubs. This study provides the first comprehensive report of the development of functional brain networks at a 3-month interval throughout the first postnatal year of life, which provides essential information to the future neurodevelopmental and developmental disorder studies.
∙A modularity and hub study at every 3 months in the first postnatal year∙Brains functional networks are gradually subdivided in the first postnatal year∙Connector hubs are spatially expanded, whereas provincial hubs are shrinking∙Different regions have distinct developmental trajectories toward hubs
Two different terminal alkynes now can be coupled together in the presence of NiCl2·6H2O/CuI by using an excess of one of the terminal alkyne substrates. The new method employed 20 mol % TMEDA as the ...ligand and environmentally benign O2 or air as the oxidant. It is the first example using Ni-salt as catalyst by employing air or O2 as oxidant, which led to efficient heterocoupling of two different alkynes.
Adult brains are functionally flexible, a unique characteristic that is thought to contribute to cognitive flexibility. While tools to assess cognitive flexibility during early infancy are lacking, ...we aimed to assess the spatiotemporal developmental features of “neural flexibility” during the first 2 y of life. Fifty-two typically developing children 0 to 2 y old were longitudinally imaged up to seven times during natural sleep using resting-state functional MRI. Using a sliding window approach, MR-derived neural flexibility, a quantitative measure of the frequency at which brain regions change their allegiance from one functional module to another during a given time period, was used to evaluate the temporal emergence of neural flexibility during early infancy. Results showed that neural flexibility of whole brain, motor, and high-order brain functional networks/regions increased significantly with age, while visual regions exhibited a temporally stable pattern, suggesting spatially and temporally nonuniform developmental features of neural flexibility. Additionally, the neural flexibility of the primary visual network at 3 mo of age was significantly and negatively associated with cognitive ability evaluated at 5/6 y of age. The “flexible club,” comprising brain regions with neural flexibility significantly higher than whole-brain neural flexibility, were consistent with brain regions known to govern cognitive flexibility in adults and exhibited unique characteristics when compared to the functional hub and diverse club regions. Thus, MR-derived neural flexibility has the potential to reveal the underlying neural substrates for developing a cognitively flexible brain during early infancy.
A D−A type of luminophore, TPA-CDP, was designed and synthesized by using triphenylamine (TPA) as D (electron donor), 1,3-diaryl pyrazole with cyano groups (CDP) as A (electron acceptor) and ...employing a cyanovinyl segment as a recognition group. Firstly, TPA-CDP demonstrates effective fluorescence quenching as a sensor for I− by the nucleophilic addition reaction of the cyanovinyl segment with a high level of sensitivity, selectivity and a low determination limit of 4.43 μM. Interestingly, TPA-CDP exhibited an AIE phenomenon with the fw value reaching 50%. In addition, TPA-CDP displayed distinct mechanochromic fluorescence behavior with 70 nm red shift, which was observed over four repeated cycles. Furthermore, the mechanochromic fluorescence behavior of TPA-CDP, as observed in powder XRD experiments, was found to be associated with the morphological transition from a crystalline state to an amorphous state. These results confirm the significant potential of CDP as a powerful electron-deficient component in the creation of D−A-type mechanochromic fluorescence materials and biosensors for detecting I−.
The objective of this study was to examine associations of lifetime concussion history (CHx) and an advanced metric of lifetime repetitive head impact exposure with resting-state functional ...connectivity (rsFC) across the whole-brain and among large-scale functional networks (Default Mode; Dorsal Attention; and Frontoparietal Control) in former collegiate football players. Individuals who completed at least one year of varsity collegiate football were eligible to participate in this observational cohort study (n = 48; aged 36–41 years; 79.2% white/Caucasian; 12.5±4.4 years of football played; all men). Individuals were excluded if they reported history/suspicion of psychotic disorder with active symptoms, contraindications to participation in study procedures (e.g., MRI safety concern), or inability to travel. Each participant provided concussion and football playing histories. Self-reported concussion history was analyzed in two different ways based on prior research: dichotomous “High” (≥3 concussions; n = 28) versus “Low” (<3 concussions; n = 20); and four ordinal categories (0–1 concussion n = 19; 2–4 concussions n = 8; 5–7 concussions n = 9; and ≥8 concussions n = 12). The Head Impact Exposure Estimate (HIEE) was calculated from football playing history captured via structured interview. Resting-state fMRI and T1-weighted MRI were acquired and preprocessed using established pipelines. Next, rsFC was calculated using the Seitzman et al., (2020) 300-ROI functional atlas. Whole-brain, within-network, and between-network rsFC were calculated using all ROIs and network-specific ROIs, respectively. Effects of CHx and HIEE on rsFC values were examined using separate multivariable linear regression models, with a-priori α set to 0.05. We observed no statistically significant associations between rsFC outcomes and either CHx or HIEE (ps ≥ .12). Neither CHx nor HIEE were associated with neural signatures that have been observed in studies of typical and pathological aging. While CHx and repetitive head impacts have been associated with changes in brain health in older former athletes, our preliminary results suggest that associations with rsFC may not be present in early midlife former football players.
The objective of this study was to examine associations of lifetime concussion history (CHx) and an advanced metric of lifetime repetitive head impact exposure with resting-state functional ...connectivity (rsFC) across the whole-brain and among large-scale functional networks (Default Mode; Dorsal Attention; and Frontoparietal Control) in former collegiate football players. Individuals who completed at least one year of varsity collegiate football were eligible to participate in this observational cohort study (n = 48; aged 36-41 years; 79.2% white/Caucasian; 12.5±4.4 years of football played; all men). Individuals were excluded if they reported history/suspicion of psychotic disorder with active symptoms, contraindications to participation in study procedures (e.g., MRI safety concern), or inability to travel. Each participant provided concussion and football playing histories. Self-reported concussion history was analyzed in two different ways based on prior research: dichotomous "High" (≥3 concussions; n = 28) versus "Low" (<3 concussions; n = 20); and four ordinal categories (0-1 concussion n = 19; 2-4 concussions n = 8; 5-7 concussions n = 9; and ≥8 concussions n = 12). The Head Impact Exposure Estimate (HIEE) was calculated from football playing history captured via structured interview. Resting-state fMRI and T1-weighted MRI were acquired and preprocessed using established pipelines. Next, rsFC was calculated using the Seitzman et al., (2020) 300-ROI functional atlas. Whole-brain, within-network, and between-network rsFC were calculated using all ROIs and network-specific ROIs, respectively. Effects of CHx and HIEE on rsFC values were examined using separate multivariable linear regression models, with a-priori α set to 0.05. We observed no statistically significant associations between rsFC outcomes and either CHx or HIEE (ps ≥ .12). Neither CHx nor HIEE were associated with neural signatures that have been observed in studies of typical and pathological aging. While CHx and repetitive head impacts have been associated with changes in brain health in older former athletes, our preliminary results suggest that associations with rsFC may not be present in early midlife former football players.
Human brain undergoes rapid growth during the first few years of life. While previous research has employed graph theory to study early brain development, it has mostly focused on the topological ...attributes of the whole brain. However, examining regional graph-theory features may provide unique insights into the development of cognitive abilities. Utilizing a large and longitudinal rsfMRI dataset from the UNC/UMN Baby Connectome Project, we investigated the developmental trajectories of regional efficiency and evaluated the relationships between these changes and cognitive abilities using Mullen Scales of Early Learning during the first twenty-eight months of life. Our results revealed a complex and spatiotemporally heterogeneous development pattern of regional global and local efficiency during this age period. Furthermore, we found that the trajectories of the regional global efficiency at the left temporal occipital fusiform and bilateral occipital fusiform gyri were positively associated with cognitive abilities, including visual reception, expressive language, receptive language, and early learning composite scores (P < 0.05, FDR corrected). However, these associations were weakened with age. These findings offered new insights into the regional developmental features of brain topologies and their associations with cognition and provided evidence of ongoing optimization of brain networks at both whole-brain and regional levels.
•Our paper charts brain functional development on a day-by-day basis.•Regional efficiencies show spatiotemporal heterogeneous development related to regional functional roles.•The developmental trajectories of regional global efficiency at the fusiform are positively associated with cognitive abilities.
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•A new nanocomposite (MMS/CS) containing CS, thioether and MMS moieties was developed.•Thiol-ene click reaction was applied to overcome the drawbacks of cross-linking method.•The ...MMS/CS exhibited selective Hg(II) capture and excellent adsorption ability.•Hg(II) loaded spent adsorbent could be utilized as an efficient catalyst.
Development of multifunctional bioadsorbents by a simple method for selective capture of the toxic Hg(II) from aqueous media, and subsequent reuse of the spent Hg(II) adsorbents as efficient heterogeneous catalysts are of great interest but remains a great challenge. Hence, in this work, a novel magnetic mesoporous silica/chitosan (MMS/CS) composite was facilely synthesized via the thiol-ene click reaction strategy to overcome the drawbacks of conventional cross-linking methods. The obtained materials were characterized by FTIR, XRD, SEM, XPS analyses. The uptake of Hg(II) by MMS/CS was systematically investigated under different parameters. Kinetic studies indicate that the sorption equilibrium can be reached within 20 min and sorption process fits well to the pseudo-second-order model. Sorption isotherm is well described by Langmuir model with the maximum sorption capacity of 478.47 mg/g at 298 K. Which represent a better Hg(II) uptake capacity and rate than the concerned materials previously reported. Besides, the coexisting ions exhibit little competition effluence on Hg(II) uptake. What’s more, the Hg(II) loaded MMS/CS can be used as an efficient catalyst to transform the phenylacetylene into acetophenone with yield of 98.3%. Therefore, this work not only demonstrates thiol-ene click reaction is a new and facile method for preparing chitosan-based functional materials with promising uptake capacity for Hg(II), but also provides a new approach for reusing of Hg(II) adsorbed material for catalytic application, thus expand the application of chitosan and magnetic mesoporous silica in diverse scientific fields.
The metal-organic frameworks/cotton fabric composites (MOFs/CFCs) have emerged as a new type of prospective materials for environmental cleanup, due to their convenient recyclability and high removal ...efficiency towards hazardous pollutants. However, their practical applications are limited by complicated synthetic conditions, insufficient interface bonding and poor adsorption capacity. Herein, for the first time, a robust ethylenediaminetetraacetic acid (EDTA)-functionalized MOFs/CFC is prepared based on UiO-66-NH2 crystals by using EDTA dianhydride as the cross-linking agent, and applied for simultaneous removal of heavy metals and dyes, as well as degradation of chemical warfare agents. The as-prepared EDTA-UiO-66-NH2/CFC shows extraordinary monocomponent adsorption performance with maximum adsorption capacity of 158.7, 126.2, 131.5, 117.4 and 104.5 mg/g for Cd(II), Cu(II), methylene blue, crystal violet and safranin O, respectively. Interestingly, in metal-dyes binary system, the uptake of Cu(II) by EDTA-UiO-66-NH2/CFC increases significantly when co-existing high concentration of dyes. The results indicate that the synergistic and simultaneous removal of both dyes and metal from complex systems can be realized by EDTA-UiO-66-NH2/CFC via multiple mechanisms. The EDTA-UiO-66-NH2/CFC also exhibits an outstanding catalytic performance for degrading dimethyl 4-nitrophenylphosphate. Besides, it can be reused for several times without obvious decrease of its adsorption and catalysis efficiencies. More impressively, the cross-linking reaction approach can not only anchor UiO-66-NH2 crystals firmly onto cotton fabric, but also facilitate in-situ formation of abundant adsorption sties on the adsorbent surface. Therefore, this work offers a simple and versatile synthetic strategy to develop high-performance environmental material for multiple pollutants remediation.
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•A simple and versatile synthetic strategy to develop high-performance environmental material.•Efficient and simultaneous adsorption of metal and dye pollutants.•EDTA dianhydride act as cross-linking agent and in-situ formation of chelating sites for metals.•EDTA-UiO-66-NH2/CFC exhibits excellent catalytic property in DMNP degradation.
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