Publications by authors named "Chang Da"

How emerging adulthood, a period particularly susceptible to the onset of mental disorders, responds to acute aerobic exercise effects on mood and brain remains an open question. A challenge in addressing this question is the scarcity of open data derived from scientific intervention paradigms. We recruited 83 healthy volunteers aged 17 to 24, who were randomly assigned to either an exercise group or a control group.

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Background: Entropy trajectories remain unclear for the aging process of human brain system due to the lacking of longitudinal neuroimaging resource.

Results: We used open data from an accelerated longitudinal cohort (PREVENT-AD) that included 24 healthy aging participants followed by 4 years with 5 visits per participant to establish cortical entropy aging curves and distinguish with the effects of age and cohort. This reveals that global cortical entropy decreased with aging, while a significant cohort effect was detectable that people who were born earlier showed higher cortical entropy.

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Adverse perinatal factors can interfere with the normal development of the brain, potentially resulting in long-term effects on the comprehensive development of children. Presently, the understanding of cognitive and neurodevelopmental processes under conditions of adverse perinatal factors is substantially limited. There is a critical need for an open resource that integrates various perinatal factors with the development of the brain and mental health to facilitate a deeper understanding of these developmental trajectories.

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In this work, we have fabricated a novel Fenton-like ferrihydrite/MoS (Fh/MoS) composite and verified that the introduction of a small amount of iron on the surface of MoS can directly promote the exposure of Mo, finally enhancing the catalytic activity of the catalyst. Even though the content of iron element is only 1.19% in the composite, the reaction rate constant of Fh/MoS system for the degradation of environmental pollutants, such as organic dyes, antibiotic, and ionic liquid, is all much better than that of pure MoS system, which is attributed to much more generation of reactive oxygen species derived from synergistic effect of Fe/Fe and Mo/Mo redox cycles.

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During the past decade, cognitive neuroscience has been calling for population diversity to address the challenge of validity and generalizability, ushering in a new era of population neuroscience. The developing Chinese Color Nest Project (devCCNP, 2013-2022), the first ten-year stage of the lifespan CCNP (2013-2032), is a two-stages project focusing on brain-mind development. The project aims to create and share a large-scale, longitudinal and multimodal dataset of typically developing children and adolescents (ages 6.

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Hypothesis: The surface of silica nanoparticles (NP) may be covalently grafted with two amino ligands to balance colloidal stability and interfacial activity via formation of in situ Janus particles. The modified NP may be combined with a like-charged diamine surfactant to create ultra-stable CO foam at low NP concentrations.

Experiments: The NP colloidal stability was measured up to 80 °C in 230 g/L TDS brine with dynamic light scattering.

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Background: Medical schools have undergone a period of continual curricular change in recent years, particularly with regard to pre-clinical education. While these changes have many benefits for students, the impact on faculty is less clear.

Methods: In this study, faculty motivation to teach in the pre-clinical medical curriculum was examined using self-determination theory (SDT) as a framework.

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The rapid development of unconventional oil and gas resources presents challenges for foam flooding for reservoirs with high salinity and high heterogeneity at elevated temperatures. In this study, hydrophilic anionic sulfonate-modified nanoparticles (NPs) exhibited a synergistic effect with a cationic surfactant in stabilizing N/water foam in the presence of concentrated divalent ions from ambient temperature up to 70 °C. With low concentrations of both the sulfonated NPs (SNPs) and cationic surfactant, the foams remained stable for 4 days at 50 °C and atmospheric pressure, while the surfactant-stabilized foams collapsed completely in 1 day.

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Issue: Medical educators share the belief that fostering the development of lifelong learning skills is a fundamental task for teachers and learners in all stages of a physician's education: undergraduate medical education, graduate medical education, and continuing medical education. A significant challenge to developing and implementing best practices in lifelong learning is the varied interpretation and application of its related terminology, such as 'self-directed learning' in this context.

Evidence: This paper discusses the scholarly origins of key terms in lifelong learning ('self-directed learning' and 'self-regulated learning') and explores their commonalities and their common conflation.

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Brain entropy (BEN) calculated from resting state fMRI has been the subject of increasing research interest in recent years. Previous studies have shown the correlations between rest BEN and neurocognition and task performance, but how this relates to task-evoked brain activations and deactivations remains unknown. The purpose of this study is to address this open question using large data (n = 862).

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Hypothesis: Surface active anionic nanoparticles (NPs) with strategically designed covalent ligands may be combined with a liked-charged surfactant to form a highly elastic gas-water interface leading to highly stable gas/water foams.

Experiments: The colloidal stability of the NPs was determined by dynamic light scattering, and the surface elastic dilational modulus E' of the interface by sinusoidal oscillation of a pendant droplet at 0.1 Hz, which was superimposed on large-amplitude compression-expansion cycles.

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The relationship between the interfacial rheology of nanoparticle (NP) laden air-brine interfaces and NP adsorption and interparticle interactions is not well understood, particularly as a function of the surface chemistry and salinity. Herein, a nonionic ether diol on the surface of silica NPs provides steric stabilization in bulk brine and at the air-brine interface, whereas a second smaller underlying hydrophobic ligand raises the hydrophobicity to promote NP adsorption. The level of NPs adsorption at steady state is sufficient to produce an interface with a relatively strong elastic dilational modulus ' = dγ/d ln .

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The design of surface chemistries on nanoparticles (NPs) to stabilize gas/brine foams with concentrated electrolytes, especially with divalent ions, has been elusive. Herein, we tune the surface of 20 nm silica NPs by grafting a hydrophilic and a hydrophobic ligand to achieve two seemingly contradictory goals of colloidal stability in brine and high NP adsorption to yield a viscoelastic gas-brine interface. Highly stable nitrogen/water (N/brine) foams are formed with CaCl concentrations up to 2% from 25 to 90 °C.

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Chaos generation in a discrete-mode (DM) laser subject to optical feedback is experimentally explored. The results show that a DM laser with only optical feedback can produce flat broadband chaos under an optimized feedback ratio. The effect of the laser bias current on the bandwidth and flatness of chaos is also investigated.

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Better municipal solid waste (MSW) management can help to address environmental concerns and supports economic and social development. Because MSW characteristics can change over time, management strategies should also evolve and be applied correspondingly. However, many previous studies have focused on MSW characterization or investigated specific management strategies for a target MSW.

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Hypothesis: For an oil droplet on calcite with an intervening brine film, the water contact angle θ may be reduced markedly (greater water wetness) with surface modified silica nanoparticles (NP). Modification with cationic, anionic, and nonionic ligands may be used to control the nanoparticle adsorption and interactions at the oil-brine and brine-calcite interfaces to influence the rate and degree of reduction in θ.

Experiments: The colloidal stability at 25 °C was determined in concentrated divalent brine (8 wt% NaCl and 2 wt% CaCl) with dynamic light scattering, and the NP adsorption was determined on calcite.

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Cyclodextrin has been studied for more than 120 years. Due to the special structure and selectivity of the cyclodextrin cavity, native cyclodextrins, cyclodextrin derivatives and inclusion complexes have received extensive attention and are widely used in medicine, food, the environment, cosmetics, chemical analysis, separation technology, catalysts and other fields. Cyclodextrin-based materials have been applied to oilfields since the early 1980s and performed well in enhancing the performance of petroleum chemicals and improving the efficiency of oil exploration.

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Functional connectivity (FC) is fundamental to brain function and has been implicated in many neuropsychological and neuropsychiatric disorders. It is then of great scientific and clinical interest to find a non-invasive approach to modulate FC. Transcranial magnetic stimulation (TMS) is a non-invasive neuromodulational tool that can affect the target region and remote brain areas.

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Chronic smoking impairs brain functions in the prefrontal cortex and the projecting meso-cortical limbic system. The purpose of this pilot study is to examine whether modulating the frontal brain activity using high-frequency repetitive transcranial magnetic stimulation (rTMS) can improve smoking cessation and to explore the changing pattern of the brain activity after treatment. Fourteen treatment-seeking smokers were offered a program involving 10 days of rTMS treatment with a follow-up for another 25 days.

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Entropy is a fundamental trait of human brain. Using fMRI-based brain entropy (BEN) mapping, interesting findings have been increasingly revealed in normal brain and neuropsychiatric disorders. As BEN is still relatively new, an often-raised question is how much new information can this measure tell about the brain compared to other more established brain activity measures.

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The design of surfactants for CO/oil emulsions has been elusive given the low CO-oil interfacial tension, and consequently, low driving force for surfactant adsorption. Our hypothesis is that waterless, high pressure CO/oil emulsions can be stabilized by hydrophobic comb polymer surfactants that adsorb at the interface and sterically stabilize the CO droplets. The emulsions were formed by mixing with an impeller or by co-injecting CO and oil through a beadpack (CO volume fractions (ϕ) of 0.

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Entropy indicates system irregularity and the capacity for information processing. Recent research has identified interesting voxel-wise entropy distribution patterns in normal brain and its changes due to aging and brain disorders. A question of great scientific and clinical importance is whether brain entropy (BEN) can be modulated using non-invasive neuromodulations.

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Hypothesis: The viscosity and stability of CO/water foams at elevated temperature can be increased significantly with highly viscoelastic aqueous lamellae. The slow thinning of these viscoelastic lamellae leads to greater foam stability upon slowing down Ostwald ripening and coalescence. In the aqueous phase, the viscoelasticity may be increased by increasing the surfactant tail length to form more entangled micelles even at high temperatures and salinity.

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The repetitive application of transcranial magnetic stimulation (rTMS) on left dorsolateral prefrontal cortex (DLPFC) has been consistently shown to be beneficial for treating various neuropsychiatric or neuropsychological disorders, but its neural mechanisms still remain unclear. The purpose of this study was to measure the effects of high-frequency left DLPFC rTMS using cerebral blood flow (CBF) collected from 40 young healthy subjects before and after applying 20 Hz left DLPFC rTMS or SHAM stimulations. Relative CBF (rCBF) changes before and after 20 Hz rTMS or SHAM were assessed with paired-t test.

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Entropy is an important trait of brain function and high entropy indicates high information processing capacity. We recently demonstrated that brain entropy (BEN) is stable across time and differs between controls and patients with various brain disorders. The purpose of this study was to examine whether BEN is sensitive to pharmaceutical modulations with caffeine.

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