30 research outputs found
Tunable tribological properties in water-based lubrication of water-soluble fullerene derivatives via varying terminal groups
Tunable tribological properties in water-based lubrication of water-soluble fullerene derivatives via varying terminal groups
The protective effect of PL 1-3 on D-galactose-induced aging mice
The aging population has become an issue that cannot be ignored, and research on aging is receiving increasing attention. PL 1-3 possesses diverse pharmacological properties including anti-oxidative stress, inhibits inflammatory responses and anti-apoptosis. This study showed that PL 1-3 could protect mice, especially the brain, against the aging caused by D-galactose (D-gal). D-gal could cause oxidative stress, inflammation, apoptosis and tissue pathological injury and so on in aging mice. The treatment of PL 1-3 could increase the anti-oxidative stress ability in the serum, liver, kidney and brain of aging mice, via increasing the total antioxidant capacity and the levels of anti-oxidative defense enzymes (superoxide dismutase, glutathione peroxidase, and catalase), and reducing the end product of lipid peroxidation (malondialdehyde). In the brain, in addition to the enhanced anti-oxidative stress via upregulating the level of the nuclear factor erythroid 2-related factor 2 and heme oxygenase 1, PL 1-3 could improve the dysfunction of the cholinergic system via reducing the active of acetylcholinesterase so as to increase the level of acetylcholine, increase the anti-inflammatory and anti-apoptosis activities via downregulating the expressions of pro-inflammatory cytokines (interleukin-6 and tumor necrosis factor-α) and pro-apoptosis proteins (Bcl-2 associated X protein and Caspase-3) in the D-gal-induced aging mice, to enhance the anti-aging ability via upregulating the expression of sirtuin 1 and downregulating the expressions of p53, p21, and p16. Besides, PL 1-3 could reverse the liver, kidney and spleen damages induced by D-gal in aging mice. These results suggested that PL 1-3 may be developed as an anti-aging drug for the prevention and intervention of age-related diseases
Stable CsPbBr3 Achieved by PorphyrinâThiol Surface Management and Their DualâStimuli Responsive for Optical Encoding
Abstract Surface ligand management plays an essential role in improving the stability of perovskite quantum dots (QDs) and endowing them with novel property. Herein, a red fluorescence porphyrinâthiol (named PorâSH) is applied to adjust the surface and stimuli responsiveness of CsPbBr3 QDs. According to the theoretical and experimental results, PorâSH can bind tightly to the exposed Pb of CsPbBr3 QDs, thus leading to the formation of PorâSHâQDs with an excellent resistance to water and UV light. Moreover, CsPbBr3 act as energy donors to improve the photoresponse of PorâSH through energy transfer, especially when heated. Notably, the PorâSH and QDs behave differently in terms of response to the temperature in the PorâSHâQDs system. Therefore, the PorâSHâQDs are capable of reversible stimuliâresponse property in the presence of heat/cool stimuli when excited by UV light. Finally, the disposable or reversible optical encoding label based on PorâSHâQDs and QDs is obtained by combining stability and the responsiveness to stimuli. Through the selection of suitable ligands, the surface of QDs is efficiently managed, which can not only mitigate instability but also endow perovskite QDs with the responsiveness to stimuli
Adjustable Tribological Behavior of Glucose-Sensitive Hydrogels
Stimuli-responsive
hydrogels have been considered to have various
applications in numerous fields. In the present work, a double-network
(DN) hydrogel has been synthesized. The copolymers of 2-acrylamide-2-methylpropane
sulfonic acid (AMPS) and acrylamide (AM) [PÂ(AMPS-<i>co</i>-AM)] are prepared as the 1st network and polyÂ(acrylic acid) as the
2nd network. This DN hydrogel is sensitive to glucose by introducing
the glucose-sensitive group phenylboronic acid to the network. The
tribological properties of this glucose-sensitive DN hydrogel have
been investigated using a universal mechanical tester (UMT-5). The
tribological results show that the friction coefficient varied with
the glucose solution. The friction coefficient increased to a maximum
of 0.06, and finally decreased to 0.025 with the increase in the glucose
concentration. An adjustable friction coefficient of the hydrogel,
between 0.025 and 0.056, was achieved along with the change of lubricant.
According to the tribological experimental results and the analysis
of the DN structure, it can be deduced that a hydrated layer exists
in the interface of the hydrogel. The hydrated layers consisting of
water molecules are bounded with the hydrophilic group of the hydrogel
network by hydrogen bonds. The change in the number of water molecules
leads to the difference in the water content of the hydrogel, which
further resulted in the various tribological properties. In addition,
the hydrogelâs mesh size also has an impact on the change in
friction coefficient. In general, the adjustable friction of the hydrogel
in a glucose environment is achieved
Charge carrier relaxation model in disordered organic semiconductors
The relaxation phenomena of charge carrier in disordered organic semiconductors have been demonstrated and investigated theoretically. An analytical model describing the charge carrier relaxation is proposed based on the pure hopping transport theory. The relation between the material disorder, electric field and temperature and the relaxation phenomena has been discussed in detail, respectively. The calculated results reveal that the increase of electric field and temperature can promote the relaxation effect in disordered organic semiconductors, while the increase of material disorder will weaken the relaxation. The proposed model can explain well the stretched-exponential law by adopting the appropriate parameters. The calculation shows a good agreement with the experimental data for organic semiconductors
Prediction of Cholecystokinin-Secretory Peptides Using Bidirectional Long Short-term Memory Model Based on Transfer Learning and Hierarchical Attention Network Mechanism
Cholecystokinin (CCK) can make the human body feel full and has neurotrophic and anti-inflammatory effects. It is beneficial in treating obesity, Parkinsonâs disease, pancreatic cancer, and cholangiocarcinoma. Traditional biological experiments are costly and time-consuming when it comes to finding and identifying novel CCK-secretory peptides, and there is an urgent need to develop a new computational method to predict new CCK-secretory peptides. This study combines the transfer learning method with the SMILES enumeration data augmentation strategy to solve the data scarcity problem. It establishes a fusion model of the hierarchical attention network (HAN) and bidirectional long short-term memory (BiLSTM), which fully extracts peptide chain features to predict CCK-secretory peptides efficiently. The average accuracy of the proposed method in this study is 95.99%, with an AUC of 98.07%. The experimental results show that the proposed method is significantly superior to other comparative methods in accuracy and robustness. Therefore, this method is expected to be applied to the preliminary screening of CCK-secretory peptides