8 research outputs found
Electronic Structure of the PeryleneâZinc Oxide Interface: Computational Study of Photoinduced Electron Transfer and Impact of Surface Defects
The
electronic properties of dye-sensitized semiconductor surfaces consisting
of perylene chromophores chemisorbed on zinc oxide via different spacer-anchor
groups have been studied at the density-functional-theory level. The
energy distributions of the donor states and the rates of photoinduced
electron transfer from dye to surface are predicted. We evaluate in
particular the impact of saturated versus unsaturated aliphatic spacer
groups inserted between the perylene chromophore and the semiconductor
as well as the influence of surface defects on the electron-injection
rates
Antimicrobial Nonisocyanate Polyurethane Foam Derived from Lignin for Wound Healing
Medical dressings, as a cover for wounds, can replace
damaged skin
in the wound healing process to play a temporary barrier role, avoid
or control wound infection, and provide a favorable environment for
wound healing. Therefore, there is an urgent need for medical antimicrobial
dressings for the treatment of chronic wounds. Although traditional
polyurethane foam has been widely used in medical dressings, conventional
polyurethane foams are primarily prepared using nonbiocompatible isocyanate-based
compounds, which are potentially hazardous for both operators and
applications in the medical field. Here, we propose nonisocyanate
polyurethane foams naturally derived from lignin by enzymatic lignin
alkylation, cyclic carbonation modification, and polymerization with
diamine and the addition of a blowing agent. Silver nanoparticle solution
was added during foaming to confer antimicrobial properties. This
lignin-based nonisocyanate polyurethane/silver composite foam (named
NIPU foam-silver) using a green synthesis method has good mechanical
properties, which can be used to manufacture polyurethane/silver foams,
and thermal and antimicrobial properties. Notably, NIPU foam-Ag showed
more than 95% bactericidal efficacy against both Escherichia
coli and Staphylococcus aureus within 4 h. Evaluation of in vitro wounds in mice showed that this
antimicrobial composite foam rapidly promotes wound healing and repairs
damaged tissue. This suggests that this biobased biodegradable antimicrobial
foam has significant scope for clinical applications in wound management
Manganese-Doped Potassium Chloride Nanoelectrodes to Potentiate Electrochemical Immunotherapy
Hypochlorous acid (HClO), as a powerful oxidizer, is
obtained from
the oxidation of Clâ ions during the electrochemical
therapy (EChT) process for cancer therapy. However, the extracellular
generated HClO is inadequate to inhibit effective tumor cell death.
Herein, manganese-doped potassium chloride nanocubes (MPC NCs) fabricated
and modified with amphipathic polymer PEG (PMPC NCs) to function as
massive three-dimensional nanoelectrodes (NEs) were developed to enhance
the generation of HClO for electrochemical immunotherapy under an
alternating electric field. Under an square-wave alternating current
(AC) electric field, the generation of HClO was boosted by PMPC NEs
due to the enlarged active surface area, enhanced mass transfer rate,
and improved electrocatalytic activity. Notably, PMPC NEs upregulated
the intracellular HClO concentration to induce robust immunogenic
cell death (ICD) under an AC electric field. Meanwhile, the electric-triggered
release of Mn2+ effectively stimulated dendritic cells
(DCs) maturation. In vivo results illustrated that
PMPC-mediated EChT inhibited tumor growth and triggered the promotion
of the immune response to regulate the tumor immune microenvironment.
Based on the potent antitumor immunity, PMPC-mediated EChT was further
combined with an immune checkpoint inhibitor (αCTLA-4) to realize
combined EChT-immunotherapy, which demonstrated enhanced tumor inhibition
of the primary tumors and an abscopal effect on distant tumors. To
summarize, our work highlights the application of electrochemical-immunotherapy
technology in tumor therapy
Table_2_Drought resistance index screening and evaluation of lettuce under water deficit conditions on the basis of morphological and physiological differences.docx
IntroductionWater is one of the important factors affecting the yield of leafy vegetables. Lettuce, as a widely planted vegetable, requires frequent irrigation due to its shallow taproot and high leaf evaporation rate. Therefore, screening drought-resistant genotypes is of great significance for lettuce production.MethodsIn the present study, significant variations were observed among 13 morphological and physiological traits of 42 lettuce genotypes under normal irrigation and water-deficient conditions.ResultsFrequency analysis showed that soluble protein (SP) was evenly distributed across six intervals. Principal component analysis (PCA) was conducted to transform the 13 indexes into four independent comprehensive indicators with a cumulative contribution ratio of 94.83%. The stepwise regression analysis showed that root surface area (RSA), root volume (RV), belowground dry weight (BDW), soluble sugar (SS), SP, and leaf relative water content (RWC) could be used to evaluate and predict the drought resistance of lettuce genotypes. Furthermore, the drought resistance ranks of the genotypes were similar according to the drought resistance comprehensive evaluation value (D value), comprehensive drought resistance coefficient (CDC), and weight drought resistance coefficient (WDC). The cluster analysis enabled the division of the 42 genotypes into five drought resistance groups; among them, variety Yidali151 was divided into group I as a strongly drought-resistant variety, group II included 6 drought-resistant genotypes, group III included 16 moderately drought-resistant genotypes, group IV included 12 drought-sensitive genotypes, and group V included 7 highly drought-sensitive genotypes. Moreover, a representative lettuce variety was selected from each of the five groups to verify its water resistance ability under water deficit conditions. In the drought-resistant variety, it was observed that stomatal density, superoxide anion (O2.âwfi2) production rate, and malondialdehyde (MDA) content exhibited a low increase rate, while catalase (CAT), superoxide dismutase (SOD), and that peroxidase (POD) activity exhibited a higher increase than in the drought-sensitive variety.DiscussionIn summary, the identified genotypes are important because their drought-resistant traits can be used in future drought-resistant lettuce breeding programs and water-efficient cultivation.</p
Table_1_Drought resistance index screening and evaluation of lettuce under water deficit conditions on the basis of morphological and physiological differences.docx
IntroductionWater is one of the important factors affecting the yield of leafy vegetables. Lettuce, as a widely planted vegetable, requires frequent irrigation due to its shallow taproot and high leaf evaporation rate. Therefore, screening drought-resistant genotypes is of great significance for lettuce production.MethodsIn the present study, significant variations were observed among 13 morphological and physiological traits of 42 lettuce genotypes under normal irrigation and water-deficient conditions.ResultsFrequency analysis showed that soluble protein (SP) was evenly distributed across six intervals. Principal component analysis (PCA) was conducted to transform the 13 indexes into four independent comprehensive indicators with a cumulative contribution ratio of 94.83%. The stepwise regression analysis showed that root surface area (RSA), root volume (RV), belowground dry weight (BDW), soluble sugar (SS), SP, and leaf relative water content (RWC) could be used to evaluate and predict the drought resistance of lettuce genotypes. Furthermore, the drought resistance ranks of the genotypes were similar according to the drought resistance comprehensive evaluation value (D value), comprehensive drought resistance coefficient (CDC), and weight drought resistance coefficient (WDC). The cluster analysis enabled the division of the 42 genotypes into five drought resistance groups; among them, variety Yidali151 was divided into group I as a strongly drought-resistant variety, group II included 6 drought-resistant genotypes, group III included 16 moderately drought-resistant genotypes, group IV included 12 drought-sensitive genotypes, and group V included 7 highly drought-sensitive genotypes. Moreover, a representative lettuce variety was selected from each of the five groups to verify its water resistance ability under water deficit conditions. In the drought-resistant variety, it was observed that stomatal density, superoxide anion (O2.âwfi2) production rate, and malondialdehyde (MDA) content exhibited a low increase rate, while catalase (CAT), superoxide dismutase (SOD), and that peroxidase (POD) activity exhibited a higher increase than in the drought-sensitive variety.DiscussionIn summary, the identified genotypes are important because their drought-resistant traits can be used in future drought-resistant lettuce breeding programs and water-efficient cultivation.</p
Table_4_Drought resistance index screening and evaluation of lettuce under water deficit conditions on the basis of morphological and physiological differences.docx
IntroductionWater is one of the important factors affecting the yield of leafy vegetables. Lettuce, as a widely planted vegetable, requires frequent irrigation due to its shallow taproot and high leaf evaporation rate. Therefore, screening drought-resistant genotypes is of great significance for lettuce production.MethodsIn the present study, significant variations were observed among 13 morphological and physiological traits of 42 lettuce genotypes under normal irrigation and water-deficient conditions.ResultsFrequency analysis showed that soluble protein (SP) was evenly distributed across six intervals. Principal component analysis (PCA) was conducted to transform the 13 indexes into four independent comprehensive indicators with a cumulative contribution ratio of 94.83%. The stepwise regression analysis showed that root surface area (RSA), root volume (RV), belowground dry weight (BDW), soluble sugar (SS), SP, and leaf relative water content (RWC) could be used to evaluate and predict the drought resistance of lettuce genotypes. Furthermore, the drought resistance ranks of the genotypes were similar according to the drought resistance comprehensive evaluation value (D value), comprehensive drought resistance coefficient (CDC), and weight drought resistance coefficient (WDC). The cluster analysis enabled the division of the 42 genotypes into five drought resistance groups; among them, variety Yidali151 was divided into group I as a strongly drought-resistant variety, group II included 6 drought-resistant genotypes, group III included 16 moderately drought-resistant genotypes, group IV included 12 drought-sensitive genotypes, and group V included 7 highly drought-sensitive genotypes. Moreover, a representative lettuce variety was selected from each of the five groups to verify its water resistance ability under water deficit conditions. In the drought-resistant variety, it was observed that stomatal density, superoxide anion (O2.âwfi2) production rate, and malondialdehyde (MDA) content exhibited a low increase rate, while catalase (CAT), superoxide dismutase (SOD), and that peroxidase (POD) activity exhibited a higher increase than in the drought-sensitive variety.DiscussionIn summary, the identified genotypes are important because their drought-resistant traits can be used in future drought-resistant lettuce breeding programs and water-efficient cultivation.</p
Table_3_Drought resistance index screening and evaluation of lettuce under water deficit conditions on the basis of morphological and physiological differences.docx
IntroductionWater is one of the important factors affecting the yield of leafy vegetables. Lettuce, as a widely planted vegetable, requires frequent irrigation due to its shallow taproot and high leaf evaporation rate. Therefore, screening drought-resistant genotypes is of great significance for lettuce production.MethodsIn the present study, significant variations were observed among 13 morphological and physiological traits of 42 lettuce genotypes under normal irrigation and water-deficient conditions.ResultsFrequency analysis showed that soluble protein (SP) was evenly distributed across six intervals. Principal component analysis (PCA) was conducted to transform the 13 indexes into four independent comprehensive indicators with a cumulative contribution ratio of 94.83%. The stepwise regression analysis showed that root surface area (RSA), root volume (RV), belowground dry weight (BDW), soluble sugar (SS), SP, and leaf relative water content (RWC) could be used to evaluate and predict the drought resistance of lettuce genotypes. Furthermore, the drought resistance ranks of the genotypes were similar according to the drought resistance comprehensive evaluation value (D value), comprehensive drought resistance coefficient (CDC), and weight drought resistance coefficient (WDC). The cluster analysis enabled the division of the 42 genotypes into five drought resistance groups; among them, variety Yidali151 was divided into group I as a strongly drought-resistant variety, group II included 6 drought-resistant genotypes, group III included 16 moderately drought-resistant genotypes, group IV included 12 drought-sensitive genotypes, and group V included 7 highly drought-sensitive genotypes. Moreover, a representative lettuce variety was selected from each of the five groups to verify its water resistance ability under water deficit conditions. In the drought-resistant variety, it was observed that stomatal density, superoxide anion (O2.âwfi2) production rate, and malondialdehyde (MDA) content exhibited a low increase rate, while catalase (CAT), superoxide dismutase (SOD), and that peroxidase (POD) activity exhibited a higher increase than in the drought-sensitive variety.DiscussionIn summary, the identified genotypes are important because their drought-resistant traits can be used in future drought-resistant lettuce breeding programs and water-efficient cultivation.</p
Activation Energy of Organic Cation Rotation in CH<sub>3</sub>NH<sub>3</sub>PbI<sub>3</sub> and CD<sub>3</sub>NH<sub>3</sub>PbI<sub>3</sub>: Quasi-Elastic Neutron Scattering Measurements and First-Principles Analysis Including Nuclear Quantum Effects
The
motion of CH<sub>3</sub>NH<sub>3</sub><sup>+</sup> cations in the low-temperature phase of
the promising photovoltaic material methylammonium lead triiodide
(CH<sub>3</sub>NH<sub>3</sub>PbI<sub>3</sub>) is investigated experimentally
as well as theoretically, with a particular focus on the activation
energy. Inelastic and quasi-elastic neutron scattering measurements
reveal an activation energy of âŒ48 meV. Through a combination
of experiments and first-principles calculations, we attribute this
activation energy to the relative rotation of CH<sub>3</sub> against
an NH<sub>3</sub> group that stays bound to the inorganic cage. The
inclusion of nuclear quantum effects through path integral molecular
dynamics gives an activation energy of âŒ42 meV, in good agreement
with the neutron scattering experiments. For deuterated samples (CD<sub>3</sub>NH<sub>3</sub>PbI<sub>3</sub>), both theory and experiment
observe a higher activation energy for the rotation of CD<sub>3</sub> against NH<sub>3</sub>, which results from the smaller nuclear quantum
effects in CD<sub>3</sub>. The rotation of the NH<sub>3</sub> group,
which is bound to the inorganic cage via strong hydrogen bonding,
is unlikely to occur at low temperatures due to its high energy barrier
of âŒ120 meV