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"Liang, Yun"
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كيف يحكم الحزب الشيوعي الصيني
مع التغيرات التاريخية وتقلبات الزمن، ظل العالم يتساءل : من أين جاءت مكانة الحزب الشيوعي الصيني في قلوب الصينيين والعالم ؟ وكيف حاز ثقة الصينيين وتأييدهم ؟ وكيف يتغلب على الصعاب ؟ وكيف يقود الصين في ثبات لبدء رحلة الاشتراكية التحديثية الجديدة، مواجهة التغير العميق لأوضاع العالم والدولة والحزب ؟ يجيب هذا الكتاب على هذه التساؤلات عبر جوانب مختلفة من وجهات النظر ويدقق النظر ويستقصي أمور الحزب الشيوعي الصيني، فيرصد أفعاله ويبحث أقواله ويحلل إنجازاته خلال هذا الوقت الذي اقترب فيه من تحقيق النهضة العظيمة للأمة الصينية أكثر من أي فترة على مر التاريخ وذلك بتمشيط الحقب والخبرات التي مر بها الحزب الشيوعي الصيني خلال توليه الحكم.
BOOK
Self- regeneration of Au/CeO2 based catalysts with enhanced activity and ultra-stability for acetylene hydrochlorination
Replacement of Hg with non-toxic Au based catalysts for industrial hydrochlorination of acetylene to vinyl chloride is urgently required. However Au catalysts suffer from progressive deactivation caused by auto-reduction of Au(I) and Au(III) active sites and irreversible aggregation of Au(0) inactive sites. Here we show from synchrotron X-ray absorption, STEM imaging and DFT modelling that the availability of ceria(110) surface renders Au(0)/Au(I) as active pairs. Thus, Au(0) is directly involved in the catalysis. Owing to the strong mediating properties of Ce(IV)/Ce(III) with one electron complementary redox coupling reactions, the ceria promotion to Au catalysts gives enhanced activity and stability. Total pre-reduction of Au species to inactive Au nanoparticles of Au/CeO
2
&AC when placed in a C
2
H
2
/HCl stream can also rapidly rejuvenate. This is dramatically achieved by re-dispersing the Au particles to Au(0) atoms and oxidising to Au(I) entities, whereas Au/AC does not recover from the deactivation.
Despite the extensive efforts to stabilize Au catalysts for industrial hydrochlorination of acetylene to vinyl chloride the deactivation is not overcome yet. Here, the authors demonstrate that the ceria promotion to Au catalysts affords enhanced activity and stability via formation of Au(0)/Au(I) as new active pairs.
Journal Article
The oncometabolite 2-hydroxyglutarate produced by mutant IDH1 sensitizes cells to ferroptosis
Ferroptosis is a non-apoptotic form of cell death characterized by the iron-dependent lipid peroxidation and is implicated in several human pathologies, such as tissue ischemia, neurodegeneration, and cancer. Ferroptosis appears to be high cell-context dependent and the regulation of ferroptosis by physiological or pathological conditions are unclear. Here, we report that tumor-derived
IDH1
mutation sensitizes cells to ferroptosis. Deletion of the mutant
IDH1
allele in
IDH1
heterozygous tumor cells or pharmacological inhibition of mutant IDH1 to produce the oncometabolite D-2-hydroxyglutarate (D-2-HG) confers resistance to erastin-induced ferroptosis. Conversely, ectopic expression of mutant IDH1 or treatment of cells with cell-permeable D-2-HG promotes the accumulation of lipid reactive oxygen species (ROS) and subsequently ferroptosis. Mechanistically, mutant IDH1 reduces the protein level of the glutathione peroxidase 4 (GPX4), a key enzyme in removing lipid ROS and ferroptosis, and promotes depletion of glutathione. Our results uncover a new role of mutant
IDH1
and 2-HG in ferroptosis.
Journal Article
Hydrogen radical-boosted electrocatalytic CO2 reduction using Ni-partnered heteroatomic pairs
The electrocatalytic reduction of CO
2
to CO is slowed by the energy cost of the hydrogenation step that yields adsorbed *COOH intermediate. Here, we report a hydrogen radical (H•)-transfer mechanism that aids this hydrogenation step, enabled by constructing Ni-partnered hetero-diatomic pairs, and thereby greatly enhancing CO
2
-to-CO conversion kinetics. The partner metal to the Ni (denoted as M) catalyzes the Volmer step of the water/proton reduction to generate adsorbed *H, turning to H•, which reduces CO
2
to carboxyl radicals (•COOH). The Ni partner then subsequently adsorbs the •COOH in an exothermic reaction, negating the usual high energy-penalty for the electrochemical hydrogenation of CO
2
. Tuning the H adsorption strength of the M site (with Cd, Pt, or Pd) allows for the optimization of H• formation, culminating in a markedly improved CO
2
reduction rate toward CO production, offering 97.1% faradaic efficiency (FE) in aqueous electrolyte and up to 100.0% FE in an ionic liquid solution.
Commercially viable catalytic CO
2
electroreduction to CO would enable many green technologies, yet it is impeded by the initial hydrogenation step of CO
2
. Here, the authors report Ni-Cd dual atom catalysts with complementary properties of favorable adsorption of CO
2
and H to overcome this barrier.
Journal Article
Highly defective graphene quantum dots-doped 1T/2H-MoS2 as an efficient composite catalyst for the hydrogen evolution reaction
We present a new composite catalyst system of highly defective graphene quantum dots (HDGQDs)-doped 1T/2H-MoS 2 for efficient hydrogen evolution reactions (HER). The high electrocatalytic activity, represented by an overpotential of 136.9 mV and a Tafel slope of 57.1 mV/decade, is due to improved conductivity, a larger number of active sites in 1T-MoS 2 compared to that in 2H-MoS 2 , and additional defects introduced by HDGQDs. High-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS) were used to characterize both the 1T/2H-MoS 2 and GQDs components while Fourier-transform infrared spectroscopy (FTIR) was employed to identify the functional groups on the edge and defect sites in the HDGQDs. The morphology of the composite catalyst was also examined by field emission scanning electron microscopy (FESEM). All experimental data demonstrated that each component contributes unique advantages that synergistically lead to the significantly improved electrocatalytic activity for HER in the composite catalyst system.
Journal Article
Machine Learning-Based Prediction of Air Quality
Air, an essential natural resource, has been compromised in terms of quality by economic activities. Considerable research has been devoted to predicting instances of poor air quality, but most studies are limited by insufficient longitudinal data, making it difficult to account for seasonal and other factors. Several prediction models have been developed using an 11-year dataset collected by Taiwan’s Environmental Protection Administration (EPA). Machine learning methods, including adaptive boosting (AdaBoost), artificial neural network (ANN), random forest, stacking ensemble, and support vector machine (SVM), produce promising results for air quality index (AQI) level predictions. A series of experiments, using datasets for three different regions to obtain the best prediction performance from the stacking ensemble, AdaBoost, and random forest, found the stacking ensemble delivers consistently superior performance for R2 and RMSE, while AdaBoost provides best results for MAE.
Journal Article
Stepwise Size Shrinkage Cascade‐Activated Supramolecular Prodrug Boosts Antitumor Immunity by Eliciting Pyroptosis
Effective pyroptosis induction is a promising approach to potentiate cancer immunotherapy. However, the actual efficacy of the present pyroptosis inducers can be weakened by successive biological barriers. Here, a cascaded pH‐activated supramolecular nanoprodrug (PDNP) with a stepwise size shrinkage property is developed as a pyroptosis inducer to boost antitumor immune response. PDNPs comprise multiple poly(ethylene glycol) (PEG) and doxorubicin (DOX) drug–polymer hybrid repeating blocks conjugated by ultra‐pH‐sensitive benzoic imine (bzi) and hydrazone (hyd) bonds. The PEG units endow its “stealth” property and ensure sufficient tumor accumulation. A sharp switch in particle size and detachment of PEG shielding can be triggered by the acidic extracellular pH to achieve deep intratumor penetration. Following endocytosis, second‐stage size switching can be initiated by more acidic endolysosomes, and PDNPs disassociate into ultrasmall cargo to ensure accurate intracellular delivery. The cascaded pH activation of PDNPs can effectively elicit gasdermin E (GSDME)‐mediated pyroptosis to enhance the immunological response. In combination with anti‐PD‐1 antibody, PDNPs can amplify tumor suppression and extend the survival of mice, which suggests a powerful immune adjuvant and pave the way for high‐efficiency immune checkpoint blockade therapy. A cascaded pH‐activated supramolecular nanoprodrug (PDNP) with mutistage size shrinkage property is developed to combat the successive drug delivery barriers. The size‐transformable PDNPs can precise intracellular delivery drug for effectively eliciting pyroptosis and augmenting antitumor immune response, favorable for boosting checkpoint blockade‐based immunotherapy.
Journal Article
Uric Acid Induces Endothelial Dysfunction by Activating the HMGB1/RAGE Signaling Pathway
Uric acid (UA) is a risk factor for endothelial dysfunction, a process in which inflammation may play an important role. UA increases high mobility group box chromosomal protein 1 (HMGB1) expression and extracellular release in endothelial cells. HMGB1 is an inflammatory cytokine that interacts with the receptor for advanced glycation end products (RAGE), inducing an oxidative stress and inflammatory response, which leads to endothelial dysfunction. In this study, human umbilical vein endothelial cells (HUVECs) were incubated with a high concentration of UA (20 mg/dL) after which endothelial function and the expression of HMGB1, RAGE, nuclear factor kappa B (NF-κB), inflammatory cytokines, and adhesion molecules were evaluated. UA inhibited endothelial nitric oxide synthase (eNOS) expression and nitric oxide (NO) production in HUVECs, increased intracellular HMGB1 expression and extracellular HMGB1 secretion, and upregulated RAGE expression. UA also activated NF-κB and increased the level of inflammatory cytokines. Blocking RAGE significantly suppressed the upregulation of RAGE and HMGB1 and prevented the increase in DNA binding activity of NF-κB and the levels of inflammatory cytokines. It also blocked the decrease in eNOS expression and NO production induced by UA. Our results suggest that high concentrations of UA cause endothelial dysfunction via the HMGB1/RAGE signaling pathway.
Journal Article
Present status, future trends, and control strategies of invasive alien plants in China affected by human activities and climate change
Invasive alien plants (IAPs) have serious environmental and economic impacts, especially in vulnerable areas of China. However, IAP richness distribution patterns, their driving factors, and the dynamic shifts in potential distribution areas remain elusive. We assessed IAP richness distribution patterns and drivers using 402 IAPs recorded in China at 88 926 occurrence points, and then predicted their potential distribution areas. The results show that IAP hotspots were mainly located in southeastern China, especially coastal areas of the South and East and large inland cities. Population density, gross domestic product (GDP), and four climate variables associated with precipitation and temperature jointly influenced the richness distribution pattern of all IAPs. Specifically, population density and GDP impacted the richness distribution pattern of narrow‐range IAPs, and population density, GDP, distance to the nearest national highway, and five climate variables affected the richness distribution pattern of widespread IAPs. Only GDP contributed significantly to the richness distribution pattern of the top 5% hotspot grid cells, whereas population density, GDP, and precipitation in the driest month (BIO14) significantly influenced the richness distribution patterns of hotspots for both the top 10% and top 20%. Prediction analysis demonstrated that southeastern China would have particularly high invasion risk under both current and future climate scenarios. Regions with increases in predicted species richness are more common (44.83–64.97%) than those with decreases, except under the Representative Concentration Pathway (RCP) 4.5 scenario. Climate change will contribute greatly to the expansion of potential IAP distribution areas under both optimistic (RCP 2.5) and pessimistic scenarios (RCP 8.5). The results of this study provide insights into the priority management of IAPs by developing promising strategies for the control and prevention of IAP invasion.
Journal Article