China’s past economic growth has substantially relied on fossil fuels, causing serious air pollution issues. Decoupling economic growth and pollution has become the focus in developing ecological ...civilization in China. We have analyzed the three-decade progress of air pollution controls in China, highlighting a strategic transformation from emission control toward air quality management. Emission control of sulfur dioxide (SO2) resolved the deteriorating acid rain issue in China in 2007. Since 2013, control actions on multiple precursors and sectors have targeted the reduction of the concentration of fine particulate matter (PM2.5), marking a transition to an air-quality-oriented strategy. Increasing ozone (O3) pollution further requires O3 and PM2.5 integrated control strategies with an emphasis on their complex photochemical interactions. Fundamental improvement of air quality in China, as a key indicator for the success of ecological civilization construction, demands the deep de-carbonization of China’s energy system as well as more synergistic pathways to address air pollution and global climate change simultaneously.
Ammonia (NH3) plays a vital role in the formation of fine particulate matter (PM2.5). Prior studies have primarily focused on the control of agricultural NH3 emissions, the dominant source of ...anthropogenic NH3 emissions. The air quality impact from vehicular NH3 emissions, which could be particularly important in urban areas, has not been adequately evaluated. We developed high-resolution vehicular NH3 emission inventories for Beijing and Shanghai based on detailed link-level traffic profiles and conducted atmospheric simulations of ambient PM2.5 concentrations contributed by vehicular NH3 emissions. We found that vehicular NH3 emissions shared high proportions among total anthropogenic NH3 emissions in the urban areas of Beijing (86%) and Shanghai (45%), where vehicular NH3 was primarily emitted by gasoline vehicles. Local vehicular NH3 emissions could be responsible for approximately 3% of urban PM2.5 concentrations during wintertime, and the contributions could be much higher during polluted periods (∼3 μg m–3). We also showed that controlling vehicular NH3 emissions will be effective and feasible to alleviate urban PM2.5 pollution for megacities in the near future.
Abstract The temporo-parieto-occipital (TPO) junction plays a unique role in human high-level neurological functions. Long-range fibers from and to this area have been described in detail but little ...is known about short TPO tracts mediating local connectivity. In this study, we performed high angular diffusion spectrum imaging (DSI) analyses to visualize the short TPO connections in the human brain. Fiber tracking was conducted on a subject-specific approach (10 subjects) and a template of 90 subjects (NTU-90 Atlas). Three tracts were identified: posterior segment of the superior longitudinal fasciculus (SLF-V), connecting the posterior part of the middle and inferior temporal gyri with the angular gyrus and supramarginal gyrus, vertical occipital fasciculus (VOF), connecting the inferior parietal with the lower temporal and occipital lobe, and a novel temporo-parietal (TP) connection, interconnecting the inferior temporal gyrus, middle temporal gyrus and fusiform gyrus, and inferior occipital lobe with the superior parietal lobe. These studies were complemented by fiber dissection techniques. It is the first study that demonstrated the trajectory and connectivity of the VOF using fiber dissection, as well as displayed the spatial relationship of the SLF-V with the cortex and the adjacent fiber bundles on one dissecting hemisphere. By providing a more accurate and detailed description of the local connectivity of the TPO junction, our findings help to develop new insights into its functional role in the human brain.
Microglia-mediated neuroinflammation plays an important role in focal ischemic stroke, a disorder with no effective therapeutic agents. Since microglial polarization to the M2 phenotype and reduction ...of oxidative stress are mediated through AMP-activated protein kinase (AMPK) and nuclear factor erythroid 2-related factor 2 (Nrf2) activation, we assessed the dual therapeutic effect of AMPK and Nrf2 activation by a novel neuroprotectant HP-1c in the treatment of ischemic stroke.
We developed a novel class of hybrids (HP-1a-HP-1f) of telmisartan and 2-(1-hydroxypentyl)-benzoate (HPBA) as a ring-opening derivative of NBP. The most promising hybrid, HP-1c, exhibited more potent anti-inflammatory and neuroprotective effects in vitro and reduced brain infarct volume and improved neurological deficits in a rat model of transient focal cerebral ischemia when compared with telmisartan alone, NBP alone, or a combination of telmisartan and NBP. HP-1c had a therapeutic window of up to 24 h, ameliorated ischemic cerebral injury in permanent focal cerebral ischemia, and improved motor function. The beneficial effects of HP-1c in ischemic stroke were associated with microglial polarization to the M2 phenotype and reduced oxidative stress. HP-1c also shifted the M1/M2 polarization in a mouse neuroinflammatory model. The anti-inflammatory and anti-oxidative effects of HP-1c were associated with AMPK-Nrf2 pathway activation for neuroprotection. We showed that HP-1c penetrates the brain, has a plasma half-life of around 3.93 h, and has no toxicity in mice. Innovation and Conclusion: Our study results suggest that HP-1c, with dual AMPK- and Nrf2-activating properties, may have potential in further studies as a novel therapy for ischemic stroke. Antioxid. Redox Signal. 28, 141-163.
Three basic deformation modes of an object (bending, twisting, and contraction/extension) along with their various combinations and delicate controls lead to diverse locomotion. As a result, seeking ...mechanisms to achieve simple to complex deformation modes in a controllable manner is a focal point in related engineering fields. Here, a pneumatic-driven, origami-based deformation unit that offers all-purpose deformation modes, namely, three decoupled basic motion types and four combinations of these three basic types, with seven distinct motion modes in total through one origami module, was created and precisely controlled through various pressurization schemes. These all-purpose origami-based modules can be readily assembled as needed, even during operation, which enables plug-and-play characteristics. These origami modules with all-purpose deformation modes offer unprecedented opportunities for soft robots in performing complex tasks, which were successfully demonstrated in this work.
As a key component in non-enzyme resistance system, flavonoids play a crucial role in the plant growth and defenses, which are significantly affected by biotic and abiotic factors such as fungi, ...bacteria, viruses, heavy metals, and atmospheric CO2. Arbuscular mycorrhizal fungi (AMF) play an important role in enhancing plant tolerance to adverse environments, which can significantly affect the synthesis of flavonoids by forming mycorrhizal symbionts with plant roots. However, few studies explored the combined effects of AMF, elevated CO2, and heavy metals on flavonoids in plants. Here, we investigated the adaptive response of flavonoids accumulation in Robinia pseudoacacia L. seedlings affected by the contamination of cadmium (Cd) and elevated CO2 to arbuscular mycorrhizal symbiosis. The results showed that G. mosseae decreased (p < 0.05) Cd content in leaves by 62.2% under elevated CO2. Moreover, G. mosseae colonization led to significant decreases in robinin, quercetin, kaempferol and acacetin by 17.4%, 11.1%, 15.5% and 23.1% under elevated CO2 + Cd, respectively. Additionally, G. mosseae down-regulated (p < 0.05) expression levels of phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS) genes under elevated CO2 + Cd, and CHS and uridine diphosphate flavonoid glucosyltransferase (UFGT) activities decreased (p < 0.05). Quercetin, kaempferol and acacetin showed positive (p < 0.05) correlation with PAL and CHS genes expression and PAL, CHS, and UFGT activities. Cadmium, C/N ratio, carotenoids, leaf biomass, total chlorophyll, P, and starch in leaves and G. mosseae colonization rate in roots influenced (p < 0.05) flavonoids content. Overall, G. mosseae reduced flavonoids synthesis by down-regulating gene expression levels and activities of key enzymes under elevated CO2 + Cd. The results improved our understanding of the regulation of AMF on non-enzymatic resistance of plants grown in heavy metal-contaminated soils under increasing atmospheric CO2 scenarios.
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•G. mosseae reduced Cd uptake by R. pseudoacacia leaves upon elevated CO2 (eCO2).•G. mosseae down-regulated expression of PAL and CHS genes under eCO2 + Cd.•G. mosseae decreased CHS and UFGT activities under the combination of eCO2 and Cd.•G. mosseae lowered robinin, quercetin, kaempferol, and acacetin under eCO2 + Cd.
MicroRNAs (miRNAs) play crucial roles in tumor initiation and development. Previously, we indicated that miR-504 is downregulated and suppresses tumor proliferation in glioblastoma (GBM). However, ...the regulation and relevant mechanism of miR-504 in GBM mesenchymal (ME) transition remain unclear.
Transcriptome and clinical data were obtained from The Cancer Genome Atlas (TCGA) database. The potential functions of miR-504 were predicted using gene ontology analysis. GBM cell migration and invasion were examined using wound healing and Transwell assays. Epithelial-mesenchymal transition (EMT) progression in GBM cell lines was detected with immunofluorescence and western blotting. The stemness activity of glioma stem-like cells (GSCs) was assessed by sphere formation assay and tumor xenograft model. miR-504 binding to the FZD7 (frizzled class receptor 7) 3' untranslated region (3'UTR) was validated using dual luciferase reporter assay. TOP/FOP Flash assays were conducted to determine the effects of miR-504 on Wnt/β-catenin signaling.
Analysis of TCGA transcriptomic data showed that low miR-504 expression correlated with ME subtype transition and poor survival in patients with GBM. Functional experiments showed that miR-504 overexpression suppressed malignant behaviors of GBM cells, such as migration, invasion, EMT, and stemness activity. Furthermore, miR-504 was a negative regulator of the Wnt-β-catenin pathway by directly repressing FZD7 expression, and FZD7 overexpression reversed the EMT inhibition caused by miR-504. Moreover, the low miR-504/FZD7 expression ratio was a ME subtype marker and could serve as a significant prognostic indicator and predict the clinical outcome of chemotherapy and radiotherapy for patients with GBM in TCGA dataset.
Our results suggest that miR-504 suppresses the aggressive biological processes associated with the ME phenotype of GBM and could be a potential candidate for therapeutic applications in these malignant brain tumors.
On-road vehicle emissions are a major contributor to
elevated air pollution levels in populous metropolitan areas. We developed a
link-level emissions inventory of vehicular pollutants, called ...EMBEV-Link (Link-level Emission factor Model for the BEijing Vehicle fleet),
based on multiple datasets extracted from the extensive road traffic
monitoring network that covers the entire municipality of Beijing, China
(16 400 km2). We employed the EMBEV-Link model under various traffic
scenarios to capture the significant variability in vehicle emissions,
temporally and spatially, due to the real-world traffic dynamics and the
traffic restrictions implemented by the local government. The results
revealed high carbon monoxide (CO) and total hydrocarbon (THC) emissions in
the urban area (i.e., within the Fifth Ring Road) and during rush hours,
both associated with the passenger vehicle traffic. By contrast,
considerable fractions of nitrogen oxides (NOx), fine particulate
matter (PM2.5) and black carbon (BC) emissions were present beyond the
urban area, as heavy-duty trucks (HDTs) were not allowed to drive through
the urban area during daytime. The EMBEV-Link model indicates that nonlocal
HDTs could account for 29 % and 38 % of estimated total on-road emissions of
NOx and PM2.5, which were ignored in previous conventional
emission inventories. We further combined the EMBEV-Link emission inventory
and a computationally efficient dispersion model, RapidAir®,
to simulate vehicular NOx concentrations at fine resolutions (10 m × 10 m in the entire municipality and 1 m × 1 m in the
hotspots). The simulated results indicated a close agreement with ground
observations and captured sharp concentration gradients from line sources to
ambient areas. During the nighttime when the HDT traffic restrictions are
lifted, HDTs could be responsible for approximately 10 µg m−3 of
NOx in the urban area. The uncertainties of conventional top-down
allocation methods, which were widely used to enhance the spatial resolution
of vehicle emissions, are also discussed by comparison with the EMBEV-Link
emission inventory.
Approximately, one in three ischemic stroke survivors suffered from depression, namely, post-stroke depression (PSD). PSD affects functional rehabilitation and may lead to poor quality of life of ...patients. There are numerous explanations about the etiologies of PSD. Here, we speculated that PSD are likely to be the result of specific changes in brain pathology. We hypothesized that the stroke-induced hyperactivity of hypothalamic–pituitary–adrenal (HPA) axis plays an important role in PSD. Stroke initiates a complex sequence of events in neuroendocrine system including HPA axis. The HPA axis is involved in the pathophysiology of depression, especially, the overactivity of the HPA axis occurs in major depressive disorder. This review summarizes the possible etiologies of PSD, focusing on the stroke-induced activation of HPA axis, mainly including the stress followed by severe brain damage and the proinflammatory cytokines release. The role of hyperactive of HPA axis in PSD was discussed in detail, which includes the role of high level corticotropin-releasing hormone in PSD, the effects of glucocorticoids on the alterations in specific brain structures, the expression of enzymes, excitotoxicity, the change in intestinal permeability, and the activation of microglia. The relationship between neuroendocrine regulation and inflammation was also described. Finally, the therapy of PSD by regulating HPA axis, neuroendocrine, and immunity was discussed briefly. Nevertheless, the change of HPA axis and the occurring of PSD maybe interact and promote on each other, and future investigations should explore this hypothesis in more depth.
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•The stroke-induced hyperactivity of HPA axis may plays an important role in PSD through CRH, ACTH and GCs respectively.•The roles of CRH may integrate many recognized findings in depression.•The augmented circulatory levels of GCs may cause depression by many routes, including affecting secretion of proinflammatory cytokines, etc.
Soft climbing robots have attracted much attention of researchers for their potential applications on the wall or inside the tube. However, making a soft robot climb on the outer surface of a rod or ...tube by agile and efficient motion has long been a challenge. Inspired by the winding climbing locomotion of arboreal snakes, a tethered pneumatic-actuated winding-styled soft rod-climbing robot that consists of two winding actuators and a telescopic actuator is proposed in this work. Based on constant curvature assumption, we develop a theoretical model to analyze the linear and bending motion of the actuators. We demonstrate that our robot can perform climbing locomotion similar to snakes, including turning around a corner along a rod, climbing a vertical rod with a maximum speed of 30.85 mm/s (0.193 body length/s), and carrying a larger payload (weight, 500 g, more than 25 times its self-weight) than existing soft climbing robots do on a vertical surface. In addition, the experimental tests exhibit the potential applications of the robot in special environments such as high-voltage cables, nuclear power plants, and underwater sites.
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