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1.
Int J Biol Macromol ; 265(Pt 2): 130898, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38508556

ABSTRACT

Anti-infection hydrogels have recently aroused enormous attraction, particularly in the treatment of chronic wounds. Herein, silver nanoparticle@catechol formaldehyde resin microspheres (Ag@CFRs) were fabricated by one-step hydrothermal method and subsequently encapsulated in hydrogels which were developed by Schiff base reaction between aldehyde groups in oxidized hyaluronic acid and amino groups in carboxymethyl chitosan. The developed polysaccharide hydrogel exhibited microporous structure, high swelling capacity, favorable mechanical strength, enhanced tissue adhesion and photothermal activities. Additionally, the hydrogel not only ensured long-term and high-efficiency antibacterial performance (99.9 %) toward E. coli and S. aureus, but also realized superior cytocompatibility in vitro. Moreover, based on the triple antibacterial strategies endowed by chitosan, silver nanoparticles and the photothermal properties of catechol microspheres, the composite hydrogel exhibited excellent anti-infection function, significantly downregulated inflammatory factors (TNF-α and IL-1ß) and promoted in vivo infected-wound healing. These results demonstrated that the polysaccharide hydrogel containing Ag@CFRs has great potential for infected-wounds repair.


Subject(s)
Chitosan , Metal Nanoparticles , Hydrogels/pharmacology , Silver , Escherichia coli , Microspheres , Staphylococcus aureus , Anti-Bacterial Agents/pharmacology , Catechols/pharmacology , Anti-Inflammatory Agents , Polysaccharides/pharmacology
2.
Opt Express ; 31(18): 29012-29018, 2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37710709

ABSTRACT

In this work, we experimentally investigate the nonlinear dynamics of a mid-infrared interband cascade laser (ICL) subject to optoelectronic feedback (OEF) through inspecting the time series and power spectrum of the laser output. The results show that, within the range of feedback strength limited by the experiment condition, the ICL sequentially presents stable state, continuously periodical oscillation (CPO), low-frequency regular pulse (LF-RP) and intermittent oscillation state with the increase of feedback strength. For the LF-RP state, the peak-to-peak value and the oscillation period increase with the increase of feedback strength. For the intermittent oscillation state, the time series is composed of the laminar region and burst region appeared alternately, and the average value and standard deviation for the duration of burst region gradually decrease with the increase of feedback strength.

3.
Front Chem ; 10: 910710, 2022.
Article in English | MEDLINE | ID: mdl-35665058

ABSTRACT

A series of novel galactoside derivatives containing 1,3,4-thiadiazole moiety were synthesized, and the structure of them was verified by spectroscopy of NMR and HRMS, and antifungal and antibacterial activities of them were screened. The results showed that the newly synthesized compounds had good antifungal activities. Among them, Ⅲ16, Ⅲ17, and Ⅲ19 exhibited satisfactory activities against Phytophthora infestans (P. infestans), with EC50 values of 5.87, 4.98, and 6.17 µg/ml, respectively, which were similar to those of dimethomorph (5.52 µg/ml). Meanwhile, the title compounds also possessed certain antibacterial activities.

4.
Sci Total Environ ; 807(Pt 2): 150660, 2022 Feb 10.
Article in English | MEDLINE | ID: mdl-34634339

ABSTRACT

Water hyacinth is a major aquatic plant in ecological restoration which propagates rapidly, whereas its biomass waste lacks value-added utilization routes. To address this problem, we put forth an innovative two-step carbonization strategy to convert water hyacinth to catalyst for isomerization of glucose to fructose. Through combining the hydrothermal carbonization and pyrolysis, catalyst morphology including its carbon substrate and calcium salts was successfully engineered. The prepared hydrochar-based catalyst presented an outstanding catalytic performance, the optimal of which could obtain 31% fructose yield with 89% selectivity at 120 °C for 45 min in water and maintain the reactivity for at least three runs. The catalytic reactivity was derived from the crystallization of endogenous alkaline earth calcium in water hyacinth, which was comparable to catalysts doped with expensive metals. Besides, the equipment and energy requirements for preparation were quite low-demanding (calcined only at 400 °C for 1 h). This study not only pioneers a sustainable way to upcycle aquatic biomass, but also invents a low-cost and efficient catalyst for biorefinery through the production of engineered carbon.


Subject(s)
Eichhornia , Biomass , Calcium , Glucose , Isomerism
5.
Environ Sci Pollut Res Int ; 28(37): 52547-52564, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34018105

ABSTRACT

Determine the main factors affecting carbon emissions of the Chinese steel industry is indispensable commitments to achieve the sustainable development of China. Hereby, based on the Stochastic Impacts by Regression on Population, Affluence and Technology (STIPRAT) model, this paper combines the economic growth function, carbon emission production function, and the FDI function of the Chinese steel industry, and uses the three-stage least square equation model (3SLS) to analyze the relationship between China's economic growth, carbon emissions in the steel industry, and FDI (foreign direct investment) inflows. The results document a complete two-way causal relationship of three variables in the whole country and the Western region, while the relationship in the Eastern region and the Central region is not complete. Moreover, there are no bidirectional causal relationship between carbon emissions and FDI in the Eastern region, while only bidirectional causality between carbon emissions and FDI in the Central region. These findings are of great significance for the Chinese steel industry to formulate effective emission reduction policies.


Subject(s)
Carbon , Economic Development , Carbon Dioxide/analysis , China , Investments , Steel
6.
Sci Total Environ ; 777: 146037, 2021 Jul 10.
Article in English | MEDLINE | ID: mdl-33677301

ABSTRACT

Since efficient isomerization of glucose to fructose is vital for valorizing cellulose fraction of biomass to value-added chemicals, an approach of engineering aluminum-hydrochar catalyst by impregnating aluminum on swollen cellulose derived hydrochar has been studied. The results showed that Al-hydrochar calcinated at 300°C achieved fructose yield of 26.3% in acetone/H2O reaction medium. It was found that the amorphous Al structures with nano-size on the surface of the carbon microspheres were the major contributor of the catalytic activity on glucose to fructose isomerization, while the formation of Al crystal had an inhibition effect on glucose isomerization. The deactivation study of Al-hydrochar catalysts showed the exfoliation of colloidal carbon containing aluminum active catalytic sites. This finding provides a novel strategy for efficient isomerization of glucose by Al-hydrochar prepared through hydrothermal carbonization and mild calcination activation process.


Subject(s)
Aluminum , Cellulose , Carbon , Catalysis , Glucose , Isomerism , Temperature
7.
Vascular ; 29(3): 323-329, 2021 Jun.
Article in English | MEDLINE | ID: mdl-32921291

ABSTRACT

OBJECTIVES: Aortic dissection involving the ascending aorta and aortic arch is a serious condition. Treatment using traditional surgical methods has certain disadvantages. This study investigated the effectiveness of thoracic endovascular repair of aortic dissection using an external prefenestrated stent. METHODS: We present a series of aortic dissection cases involving the ascending aorta and aortic arch treated with an external prefenestrated stent. RESULTS: Postoperative follow-up of the patients showed that all stents were released at the proper position and that branch vessels were not occluded, and there were no instances of type I endoleak. One patient died suddenly one week after surgery; another experienced retrograde type A aortic dissection in the second week; and type I endoleak occurred in one patient in the first week, although this resolved within six months. No serious complications such as cerebrovascular events, acute spinal cord ischemia, and paraplegia occurred during the perioperative period. All patients had false lumen thrombosis in the ascending aorta and aortic arch. CONCLUSION: Prefenestrated stent grafting is a feasible treatment option for repairing an entry tear in the ascending aorta.


Subject(s)
Aorta, Thoracic/surgery , Aortic Aneurysm, Thoracic/surgery , Aortic Dissection/surgery , Blood Vessel Prosthesis Implantation/instrumentation , Blood Vessel Prosthesis , Endovascular Procedures/instrumentation , Stents , Ulcer/surgery , Adult , Aged , Aortic Dissection/diagnostic imaging , Aorta, Thoracic/diagnostic imaging , Aortic Aneurysm, Thoracic/diagnostic imaging , Blood Vessel Prosthesis Implantation/adverse effects , Endovascular Procedures/adverse effects , Female , Humans , Male , Middle Aged , Postoperative Complications/etiology , Prosthesis Design , Time Factors , Treatment Outcome , Ulcer/diagnostic imaging
8.
Chemosphere ; 263: 128093, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33297089

ABSTRACT

In this study, bamboo residues derived functional hydrochar microspheres have been fabricated by different acids-assisted hydrothermal carbonization including hydrochloric aicd, sulfuric acid or nitric acid.The energy-dispersive X-ray fluorescence spectroscopy and Fourier Transform Infrared spectroscopy analyses showed that sulfur- and nitrogen-containing functional groups were grafted on the surface of hydrochar microspheres, respectively. Elemental analysis indicates that the addition of acids has a significant influence on the hydrothermal reaction pathway and promotes the hydrolysis process. When the hydrothermal carbonization temperature is 220 °C, hydrochloric acid and nitric acid can effectively overcome the agglomeration of hydrochar microspheres and form single micron carbon sphere. Irregularly shaped hydrochar particles groups were formed during sulfuric acid-assisted hydrothermal treatment. The results indicate the viability of acid assisted hydrothermal carbonization to produce the functional hydrochar microsphere using bamboo residues.


Subject(s)
Carbon , Nitrogen , Hydrolysis , Microspheres , Temperature
9.
Vascular ; 29(5): 637-643, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33308107

ABSTRACT

OBJECTIVE: The present study aims to analyze the outcomes of three cases of pre-fenestration and branch stent-graft endovascular repair of aortic disease with zone 2 aortic lesions. METHODS: From August 2017 to June 2018, three patients with zone 2 aortic lesions underwent thoracic endovascular repair with innominate artery, left common carotid artery, and left subclavian artery recannulation using pre-fenestration and branched stent-grafts to preserve the patency of the aortic arch branches. RESULTS: The technical success rate was 100%. One patient had a proximal type I endoleak with no need for additional treatment. The overall mortality was 0%. All branches were patent. The follow-up period lasted for 2-15 months, with one patient lost to follow-up. There were no conversions to open surgical repair, aortic rupture, paraplegia, or retrograde type A aortic dissection. CONCLUSION: The use of a pre-fenestration and branch stent-graft for the thoracic endovascular repair of zone 2 aortic lesions is a feasible and effective method for aortic arch branch revascularization. The risk of this surgical procedure is high, requiring significant expertise. The procedure should be conducted only in experienced centers. Durability concerns should be assessed in future studies with long-term follow-up.


Subject(s)
Aneurysm, False/surgery , Aortic Aneurysm, Thoracic/surgery , Aortic Dissection/surgery , Adult , Aged , Aortic Dissection/diagnostic imaging , Aortic Dissection/physiopathology , Aneurysm, False/diagnostic imaging , Aneurysm, False/physiopathology , Aortic Aneurysm, Thoracic/diagnostic imaging , Aortic Aneurysm, Thoracic/physiopathology , China , Female , Humans , Male , Time Factors , Vascular Patency
10.
Sci Total Environ ; 727: 138743, 2020 Jul 20.
Article in English | MEDLINE | ID: mdl-32334238

ABSTRACT

Hydrochar microspheres supported Al catalysts with hierarchically porous structure (Al/HPHMs) for glucose to fructose isomerization were fabricated. Superior catalytic selectivity (93.3%) and fructose yield (32.6%) were achieved in aqueous under 160 °C for 20 min. Hierarchically porous structure was formed after KHCO3 and K2CO3 activation and the roles of KHCO3 and K2CO3 in controlling the Al phase and tailoring morphology of hydrochar supported Al were evaluated. The major active sites were characterized as Al hydroxides including ß-Al(OH)3, γ-Al(OH)3, γ-AlO(OH), Al-C-O linkages. Active sites by KHCO3 activation with high contents of Al-C-O and Al(OH)3 have better selectivity. Oxygen-containing functional groups including aluminum­oxygen groups on the hydrochar microspheres have contributed to the formation of hydrogen bond and π-π interactions between glucose and Al species. Green process synthesized aluminum-hydrochars have potential for their application as a variety of stable, recyclable, and efficient catalysts for lignocellulosic biorefining.


Subject(s)
Aluminum , Carbon , Fructose , Glucose , Isomerism , Temperature
11.
Bioresour Technol ; 299: 122586, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31865154

ABSTRACT

One-step fractionation with concentrated formic acid at elevated temperatures with short retention time was investigated for corn stover valorization. Crude pulp (CP) with high purity of cellulose and FA-lignin (FAL) with high guaiacyl content were fractionated through one-step mild pretreatment. Formylation reaction on both CP and FAL fractions occurred during the pretreatment and improved the hydrophobicity and thermal stability of CPs and FALs. The presence of formyl group on CPs significantly inhibited the enzymatic hydrolysis efficiency for sugar production, however, the formylated cellulose showed super high reactivity and selectivity for HMF production through catalysis by maleic acid and aluminum chloride in acetonitrile-water co-solvent system. In addition, the fractionated FAL fraction exhibited a loose structure which is prominent for its further catalytic conversion into chemicals and energy.


Subject(s)
Lignin , Zea mays , Cellulose , Formates , Furaldehyde/analogs & derivatives , Hydrolysis
12.
J Anal Methods Chem ; 2019: 5032950, 2019.
Article in English | MEDLINE | ID: mdl-31061741

ABSTRACT

To perform accurate and synchronous detection of the soluble solid contents (SSC) in fresh jujubes at different stages of maturity, hyperspectral imaging was used to establish robust models. The combined data constituting four maturation stages were used to build the grid-search least squares support vector machine (GS-LS-SVM) model. The determination coefficient (Rp2), the root-mean-square error (RMSEP), and the residual predictive deviation (RPD) of the prediction set for samples of the overall stages were 0.98, 1.10%, and 7.85, respectively. Furthermore, a successive projections algorithm (SPA) was used to extract the characteristic wavelengths of the combined data. An artificial bee colony (ABC) algorithm (for the prediction set, Rp2 = 0.98, RMSEP = 1.19%, RPD = 7.25) was used to improve the SPA-LS-SVM model, which was better than the SPA-GS-LS-SVM model (for the prediction set, Rp2 = 0.98, RMSEP = 1.24%, RPD = 6.96). Lastly, visualization of the SSC distribution map was performed based on the SPA-ABC-LS-SVM model, which clearly showed that the SSC gradually increased during maturation. The results indicated that it was realistic to construct a detection model of the multimaturity stage. This research also demonstrated that the combination of hyperspectral imaging and the ABC had good application values in the testing of agricultural products.

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