Effective hemostasis is vital to reduce the pain and mortality of patients, and the research and development of hemostatic materials are prerequisite for effective hemostasis. Chitosan (CS), with ...good biodegradability, biocompatibility and non-toxicity, has been widely applied in bio-medicine, the chemical industry, the food industry and cosmetics. The excellent hemostatic properties of CS have been extensively studied. As a result, chitosan-based composite hemostatic materials have been emerging. In this review, the hemostatic mechanism of chitosan is briefly discussed, and then the progress of research on chitosan-based composite hemostatic materials with multiple forms such as films, sponges, hydrogels, particles and fibers are introduced. Finally, future perspectives of chitosan-based composite hemostatic materials are given. The objective of this review is to provide a reference for further research and development of effective hemostatic materials.
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•Effect of humic acid (HA) on photo(cata)lysis of tetracycline (TC) was assessed.•Photolytic degradation of TC was enhanced by HA due to photosensitization effect.•Photocatalytic ...degradation of TC was inhibited by HA through OH quenching.•Photolytic and photocatalytic degradation pathways of TC were proposed.•The yields of products were affected by HA during photolysis and photocatalysis.
The widespread occurrence of tetracycline (TC) in the aquatic environment poses a potential risk to aquatic ecosystem and human health. In this study, elimination of TC by photolysis and TiO2 photocatalysis were investigated by using mercury-free UVA-LED as an alternative light source. Particular emphasis was given to the effect of humic acid (HA) on the reaction kinetics and mechanisms of TC removal. Photolytic degradation of TC was slightly enhanced by HA due to its photosensitization effect, as evidenced by the increased steady-state concentrations of OH. The most abundant transformation product of TC, which was formed by the attack of OH radical, was enhanced during photolytic degradation. During photocatalytic experiments, HA dramatically inhibited TC loss due to the surface deactivation of TiO2 and OH quenching. The steady-state concentration of OH was dramatically decreased in the presence of HA. Identification of transformation products showed that HA could inhibit the oxidation pathways initiated by OH during photocatalysis of TC. These findings provide further insights into the assessment of photolysis and photocatalysis for antibiotics elimination in natural waters where HA exists ubiquitously.
Aromatic‐imide‐based thermally activated delayed fluorescent (TADF) enantiomers, (+)‐(S,S)‐CAI‐Cz and (−)‐(R,R)‐CAI‐Cz, were efficiently synthesized by introducing a chiral 1,2‐diaminocyclohexane to ...the achiral TADF unit. The TADF enantiomers exhibited high PLQYs of up to 98 %, small ΔEST values of 0.06 eV, as well as obvious temperature‐dependent transient PL spectra, thus demonstrating their excellent TADF properties. Moreover, the TADF enantiomers showed mirror‐image CD and CPL activities. Notably, the CP‐OLEDs with CPEL properties based on the TADF enantiomers not only achieved high EQE values of up to 19.7 and 19.8 %, but also displayed opposite CPEL signals with gEL values of −1.7×10−3 and 2.3×10−3, which represents the first CP‐OLEDs, based on the enantiomerically pure TADF materials, having both high efficiencies and intense CPEL.
It's intense: Thermally activated delayed fluorescenct (TADF) enantiomers were developed by introducing a chiral 1,2‐diaminocyclohexane to the achiral TADF unit. They exhibited high PLQYs (98 %), small ΔEST values (0.06 eV), and mirror‐image CD and CPL spectra. Moreover, they represent the first example of CP‐OLEDs, based on the enantiomerically pure TADF materials, having both high efficiencies (EQE: 19.8 %) and intense CPEL.
Ammonia synthesis is one of the most kinetically complex and energetically challenging chemical processes in industry and has used the Harber–Bosch catalyst for over a century, which is processed ...under both harsh pressure (150–350 atm) and hightemperature (623–823 K), wherein the energy and capital intensive Harber–Bosch process has a huge energy cost accounting for about 1%–3% of human's energy consumption. Therefore, there has been a rough and vigorous exploration to find an environmentally benign alternative process. As the amorphous material is in a metastable state and has many “dangling bonds”, it is more active than the crystallized one. In this paper, CeOx‐induced amorphization of Au nanoparticles anchored on reduced graphite oxide (a‐Au/CeOx–RGO) has been achieved by a facile coreduction method under ambient atmosphere. As a proof‐of‐concept experiment, a‐Au/CeOx–RGO hybrid catalyst containing the low noble metal (Au loading is 1.31 wt%) achieves a high Faradaic efficiency (10.10%) and ammonia yield (8.3 μg h−1 mg−1cat.) at −0.2 V versus RHE, which is significantly higher than that of the crystalline counterpart (c‐Au/RGO), and even comparable to the yields and efficiencies under harsh temperatures and/or pressures.
CeOx‐induced amorphization of Au nanoparticles anchored on reduced graphite oxide (a‐Au/CeOx–RGO) as a heterogeneous electrocatalyst shows excellent catalytic activity for electrochemical N2 reduction reaction with high Faradic efficiency (10.10%) and ammonia yield (8.3 μg h‐1 mg‐1cat.)
Cervical cancer is the leading cause of cancer-related deaths in women, and treatment for cervical cancer is very limited. Emerging evidence suggests that targeting ferroptosis is a promising way to ...treat cancer. Here, we investigated the role of ferroptosis in cervical cancer, with a focus on the Cdc25A/PKM2/ErbB2 axis. Cervical cancer cells were treated with sorafenib to induce ferroptosis. Cellular MDA/ROS/GSH/iron detection assays were used to measure ferroptosis. MTT assays were performed to assess cell viability. qRT-PCR, western blot, and immunostaining assays were performed to measure the levels of proteins. Autophagy was monitored by fluorescence microscopy. Nuclear and cytosolic fractions were isolated to examine the location of PKM2 modifications. Co-IP experiments were conducted to determine the Cdc25A/PKM2 interaction. ChIP assays were performed to measure the binding affinity between H3K9Ac and the ErbB3 promoter, and a dual luciferase assay was performed to examine the transcriptional activity of ErbB2. A nude mouse xenograft model was used to examine the effects of the Cdc25A/ErbB2 axis on tumour growth in vivo. Cdc25A was elevated in human cervical cancer tissues but was reduced during sorafenib-induced ferroptosis of cervical cancer cells. Overexpression of Cdc25A inhibited sorafenib-induced ferroptosis by dephosphorylating nuclear PKM2 and suppressing autophagy. Cdc25A regulated autophagy-induced ferroptosis by increasing ErbB2 levels via the PKM2-pH3T11-H3K9Ac pathway. Cdc25A increased the resistance of cervical cancer to sorafenib, while knockdown of ErbB2 blocked these effects. Cdc25A suppressed autophagy-dependent ferroptosis in cervical cancer cells by upregulating ErbB2 levels through the dephosphorylation of PKM2. These studies revealed that Cdc25A/PKM2/ErbB2 pathway-regulated ferroptosis could serve as a therapeutic target in cervical cancer.
As an alternative approach for N2 fixation under milder conditions, electrocatalytic nitrogen reduction reaction (NRR) represents a very attractive strategy for sustainable development and N2 cycle ...to store and utilize energy from renewable sources. However, the research on NRR electrocatalysts still mainly focuses on noble metals, while, high costs and limited resources greatly restrict their large‐scale applications. Herein, as a proof‐of‐concept experiment, taking PdCu amorphous nanocluster anchored on reduced graphene oxide (rGO) as NRR catalysts, the optimum Pd0.2Cu0.8/rGO composite presents a synergistic effect and shows superior electrocatalytic performance toward NRR under ambient conditions (yield: 2.80 µg h−1 mgcat.−1 at −0.2 V vs reversible hydrogen electrode), which is much higher than that of monometallic, especially noble metal, counterparts. The superior catalytic performance of alloy catalysts with low noble metal loading would strongly spur interest toward more researches on NRR catalysts in the future.
PdCu amorphous nanoclusters anchored on graphene are successfully synthesized by a facile coreduction route. The optimum Pd0.2Cu0.8/rGO sample presents enhanced electrocatalytic performance toward electrochemical N2 fixation to NH3 under ambient conditions.
An optimized macroseismic intensity index, which integrates the traditional macroseismic intensity scale and the instrument intensity evaluation model, is proposed to evaluate regional buildings’ ...empirical resilience and vulnerability. The traditional failure probability of the group structure is modified and improved. The parameters and probability indexes used to assess the resilience and vulnerability of group structure in urban and rural areas are innovatively proposed. The empirical group structure seismic loss data from the actual field investigation of the Jiuzhaigou earthquake in Sichuan Province, China, on August 8, 2017, were statistically analysed, the vulnerability of the sample data was assessed by using the optimized Chinese seismic intensity scale (OCSIS-20), European Macroseismic Scale (EMS-98) and the Modified Mercalli Intensity (MMI), and the assessment and comparison model of multidimensional modal resilience and probability index was established. To improve the rationality and accuracy of typical building resilience in the macrointensity quantification region, a new quantitative model of resilience and vulnerability based on optimizing the macrointensity index and updating the lognormal distribution is proposed, and the group structure resilience comparison models for typical macrointensity standard evaluation are established. The structural vulnerability database of the Jiuzhaigou earthquake is utilized to verify the rationality of the innovative model. Ultimately, field loss inspection and damage mechanism analysis are conducted based on the characteristics of regional structural seismic resilience and the actual vulnerability of the Jiuzhaigou earthquake.
•The rapid resilience and vulnerability prediction and evaluation domain, plane, surface, and matrix based on quantity and failure index parameters are established.•An innovative regional domain vulnerability and resilience assessment model is conducted.•A new quantitative model of resilience and vulnerability based on optimizing the macrointensity index and updating the lognormal distribution is proposed.
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•Adsorption behaviors of ibuprofen and naproxen by UiO-66 and UiO-66-NH2.•Adsorption mechanisms of ibuprofen and naproxen were revealed by DFT calculation.•π-π EDA, H-bonding, LAB ...complexing, and anion-π interaction were involved.•The binding energies followed the order of π-π > hydrogen bonding > LAB > anion-π.
Ibuprofen (IBP) and naproxen (NAP), two typical anti-inflammatory drugs, were frequently detected in natural waters. Therefore, their adsorption to various materials has drawn great interests. However, the adsorption mechanisms of IBP and NAP at a molecular level were not well-known. This study investigated the adsorption of IBP and NAP by two types of metal organic frameworks (MOFs), UiO-66 and UiO-66-NH2, and the adsorption mechanisms were revealed at macro and micro molecule levels based on experiments and density functional theory (DFT) calculations. Greater adsorption of IBP onto MOFs was observed compared with NAP, which is incurred by its higher binding energies with adsorbents than NAP as revealed by DFT calculations. Four mechanisms, including π-π EDA interaction, Lewis acid/base complexing (LAB), hydrogen bonding, and anion-π interaction, were simultaneously involved in the adsorption of IBP/NAP by MOFs. The binding energies followed the order of π-π > hydrogen bonding > LAB > anion-π. The decreasing adsorption of IBP and NAP with rising pH was induced by the facilitated aggregation of MOFs at pH < pHpzc and the electrostatic repulsion between IBP/NAP and MOFs at pH > pHpzc. Direct competition for adsorption sites accounted for the competitive adsorption between IBP and NAP, and the extra type of binding site (amino group) and less amount of adsorption sites induced the less competition between IBP and NAP onto UiO-66-NH2 compared with UiO-66. This study, at a molecular level, provides adsorption mechanisms of acidic pharmaceuticals with MOFs.
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