Peri-implantitis is characterized by inflammation resulting from bacterial infections in peri-implant connective tissue. The purpose of this study was to prepare and characterize chitosan/gelatin ...(CSG)-based membranes with antibacterial agents to functionalize the surface of titanium (Ti) implants. CSG membranes were prepared on Ti substrates via electrophoretic deposition (EPD). Quercetin, an active flavonoid responsible for fulfilling various plant functions, was introduced as an antibacterial agent to be loaded into the membrane during preparation. The fabrication of quercetin-loaded CSG membranes via EPD was also investigated. Fluorescent microscope, Attenuated Total Reflection Fourier transform infrared spectroscopy, and X-ray diffraction results verified the entrapment of quercetin. The membranes swelled by 150% of mass after rehydration. The antibacterial effects of quercetin on Gram-positive bacteria, such as Staphylococcus aureus and methicillin-resistant Staphylococcus aureus, were verified by spread-plate, scanning electron microscopy, and live/dead staining. Cytological experiments showed that the biocompatibility of rat bone marrow mesenchymal stromal cells was promoted by quercetin-loaded membranes, exclusively in the group with the highest content of quercetin. The quercetin-loaded groups also enhanced the antineoplastic activity of MG-63 cells. These results suggested that quercetin-loaded CSG membranes were successfully fabricated via EPD. Thus, biocompatible and antibacterial membranes could be a potential strategy to functionalize Ti implants.
This paper aims to investigate the confined distance near the floor(0∼28 mm) and wire size (the ratios of copper core diameter to entire wire diameter are: 6mm/8 mm,6mm/10 mm,8mm/12 mm and 6mm/12 mm ...for type Ⅰ, type Ⅱ, type Ⅲ and type Ⅳ, respectively) on the flame spread over polyethylene (PE) wires. It is indicated that, when the confined distance is relatively small, the extinction occurs for all types.The typical parameters of flame shape including of flame width, flame height and flame area, flame spread rate and mass loss rate with the increase of confined distance s can be separated into continuous growth stage and stable fluctuation stage. At the continuous growth stage, the flame area shows an exponential relationship with s as: A∼s52. And at the stable fluctuation stage, the flame width is larger than that at the unconfined condition accounting for a large portion.While, the flame height is always smaller than that in the unconfined case.In order to explicitly describe the heat transfer, the upward large main flame and downward small flame are firstly introduced in this paper. Correspondingly, the heat flux feedback of components to the preheating zone is established with the upward main flame flux q˙f(up)″ includes of q˙vf(up)″+q˙rf(up)″, the downward small flame heat flux q˙f(down)″ includes of q˙vf(down)″+q˙rf(down)″, the conductive heat flux q˙c″ and the gypsum board heat flux q˙g″. With the increase of s, q˙f(down)″ shows an increasing and then decreasing trend, making it take a second role during heat flux feedback. Meanwhile, the analysis demonstrates that for the larger copper core (type Ⅲ) and the smaller of PE thickness (type Ⅰ), the ratio of heat flux of q˙f(down)″q˙f(up)″+q˙f(down)″ will be increased, which will enhance the heat transfer effect of downward small flame.
The purpose of this article is to discuss the statistical methods for agreement analysis used in Richelle's article (BMC Med Educ 22:335, 2022). The authors investigated the attitudes of final-year ...medical students regarding substance use during pregnancy and identified the factors that influence these attitudes.
We found that Cohen's kappa value for measuring the agreement between these medical students' attitudes towards drugs/alcohol use during pregnancy was questionable. In addition, we recommend using weighted kappa instead of Cohen's kappa for agreement analysis at the presence of three categories.
The agreement improved from "good" (Cohen's kappa) to "very good" (weighted kappa) for medical students' attitudes towards drugs/alcohol use during pregnancy.
To conclude, we recognize that this does not significantly alter the conclusions of the Richelle et al. paper, but it is necessary to ensure that the appropriate statistical tools are used.
Numerous studies have shown that long noncoding RNAs (LncRNAs) are involved in the development and immune escape of head and neck squamous-cell carcinoma (HNSCC). However, the specific regulatory ...mechanisms by which LINC01123 regulates HNSCC and its correlation with immunity remain unclear. Therefore, this study's primary purpose was to explore the mechanisms by which LINC01123 regulates the immune escape and progression of HNSCC. This study confirmed that LINC01123 is competitively bound to miR-214-3p, and miR-214-3p specifically targets B7-H3. The effects of LINC01123, B7-H3, and miR-214-3p on tumor progression, CD8
T-cell-mediated immune response, and the tumorigenicity of HNSCC in vitro and in vivo were examined through the downregulation or upregulation of LINC01123, B7-H3, and miR-214-3p. Our results indicated that LINC01123 and B7-H3 were highly expressed in HNSCC and are associated with poor prognosis in patients. Notably, overexpression of LINC01123 or B7-H3 or downregulation of miR-214-3p inhibited the function of CD8
T cells and promoted the progression of HNSCC. Therefore, LINC01123 acts as a miR-214-3p sponge to inhibit the activation of CD8
T cells and promote the progression of HNSCC by upregulating B7-H3.
Leaf-chewing insects are important pests that cause yield loss and reduce seed quality in soybeans (
). Breeding soybean varieties that are resistant to leaf-chewing insects can minimize the need for ...insecticide use and reduce yield loss. The marker gene for QTL-M,
(LOC100775351) that encodes a UDP-glycosyltransferase (UGT) is the major determinant of resistance against leaf-chewing insects in soybean; it exhibits a loss of function in insect-resistant soybean germplasms. In this study,
-mediated transformation introduced the CRISPR/Cas9 expression vector into the soybean cultivar Tianlong No. 1 to generate
gene mutants. We obtained two novel types of mutations, a 33-bp deletion and a single-bp insertion in the
coding region, which resulted in an enhanced resistance to
and
. Additionally, overexpressing
produced soybean varieties that were more sensitive to
.
and
. Both mutant and overexpressing lines exhibited no obvious phenotypic changes. The difference in metabolites and gene expression suggested that
is involved in imparting resistance to leaf-chewing insects by altering the flavonoid content and expression patterns of genes related to flavonoid biosynthesis and defense. Furthermore, ectopic expression of the
gene in the
mutant of
substantially rescued the phenotype of
resistance in the
mutant. Our study presents a strategy for increasing resistance against leaf-chewing insects in soybean through CRISPR/Cas9-mediated targeted mutagenesis of the
genes.
The performance of inductive pulsed power supplies (IPPSs) is limited by excessive joule heat loss and low energy transfer efficiency. A significant reduction in the coil resistance can fundamentally ...ameliorate this problem. This article takes the meat grinder with self-charge capacitor and thyristor (SECT) circuit as an example to study the performance improvement caused by the reduction of the coil resistance. The influence of coil resistance on several performance indexes is analyzed by circuit analysis and simulation. Then, the experiment with an energy level of 40 kJ is carried out, in which the inductors have very low resistance due to immersion in liquid nitrogen. With low temperature, the charging energy and the output current peak value are increased by 37% and 19%, respectively, the pulsewidth of output current is increased by 257%, and the energy transfer capacitor is successfully self-charged compared to the performance of the same SECT circuit with room temperature. Thus, the feasibility of applying nitrogen cooling to IPPS is validated.
The multi-pass deposited metals were prepared by metal-cored wire with low (2.5 wt%) and high (4.0 wt%) Ni to research the effect of Ni on the bainite/martensite transformation. Results showed that ...deposited metals exhibited a multiphase structure comprised of bainite, martensite and residual austenite, which is not only explained from SEM/TEM, but also identified and quantified each phase from crystallographic structure through XRD and EBSD. With Ni content increasing, the fraction of martensite increases from 37% to 41%, and that of bainite decreases from 61% to 55% accordingly because 4% Ni element narrows the temperature range of the bainite transformation ~20 °C. The 7.8% residual austenite exhibited block and sheet in the deposited metal with low Ni, while the fraction of residual austenite was 3.26% as a film with high Ni, caused by different transformation mechanisms of bainite and martensite. The tensile strengths of deposited metals were 1042 ± 10 MPa (2.5% Ni) and 1040 ± 5 MPa (4% Ni), respectively. The yield strength of deposited metals with high Ni was 685 ± 18 MPa, which was higher than low Ni due to the high fraction of martensite. The impact values of deposited metals with high Ni content decreased because the volume fraction of bainite and residual austenite and area fraction of large-angle grain boundary were lower.
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•CTS-SeNPs (around 54 nm) were uniform spherical and could be stable for 60 days.•CTS-SeNPs at a dose of 2.0 mg Se/kg bw exhibited a definite antidiabetic activity.•CTS-SeNPs showed ...higher antidiabetic activity than other selenium compounds.
Chitosan-stabilized selenium nanoparticles (CTS-SeNPs) were prepared through the reduction of selenite acid with ascorbic acid. The optimal synthesis conditions of CTS-SeNPs were obtained by orthogonal experiments. Besides, the size, morphology and stability of CTS-SeNPs were characterized by transmission electron microscopy (TEM), scanning electron microscope (SEM) and dynamic light scattering (DLS). The results showed that, the CTS-SeNPs with diameter of about 54 nm could be obtained under the optimal conditions (temperature of 25 °C, reaction time of 2 h, Vc concentration of 0.04 M and the CTS concentration of 1.0 mg/mL). CTS-SeNPs were uniform spherical and could be stable for approximately 60 days at 4 °C. Further, the antidiabetic activities of CTS-SeNPs in streptozotocin (STZ)-induced diabetic mice were investigated as well. The results revealed that CTS-SeNPs at a dose of 2.0 mg Se/kg bw exhibited higher antidiabetic activity than other doses of CTS-SeNPs and other selenium compounds with the same selenium content.
The safe service of reeled-pipeline welded joint subjected to multiple cyclic plastic deformation (CPD) is challenged by hydrogen embrittlement (HE) in the process of gas and petroleum ...transportation. Therefore, this work aims to study the interrelation of hydrogen and the ductility of X65 reeled-pipeline welded joint with CPD by using electrochemical hydrogen charging. The results showed that hydrogen could lead to the ductility degradation, regardless of whether the CPD process was performed. But the hydrogen-induced ductility degradation for the welded joint with CPD was retarded. When the hydrogen-charging current density was 50 mA/cm2, the hydrogen embrittlement index (IUE) based on the uniform elongation for welded joint with CPD was 0.33, while that of as-welded joint was 0.53, which indicated that CPD process reduced the sensitivity to HE. The morphology of tensile fracture indicated that brittle cracks initiated at the composite oxide inclusion enriched Al–Mg–Ca–S elements, and propagated radially by quasi-cleavage fracture pattern. The CPD process led to the increase of dislocations acting as reversible hydrogen traps, which significantly enhanced the hydrogen content of welded joint from 1.001 ppm to 2.516 ppm. However, the dislocation walls and cells related to the CPD process hindered the diffusion of hydrogen, and homogeneous distribution of dislocations after CPD dispersed trap sites for capturing hydrogen, which played important roles in delaying hydrogen-induced fracture.
In order to solve the problem of subgrade and foundation vibration damage induced by the railway train, a new type of rubber particle-flowable fly ash (FAR) subgrade was designed based on the ...principle of damping energy dissipation. The FAR material was prepared to meet the requirements of the working performance by the laboratory test, and the mechanical properties were investigated. The damping ratio characteristics of the FAR material were studied by the transient excitation method, the influence of the rubber particle content on the damping characteristics of the FAR material was analyzed and the vibration isolation mechanism of the FAR material was revealed. A 3D numerical model of track-subgrade-foundation was established by the finite element software, and the vibration isolation performance of the FAR subgrade was analyzed based on the coupled model. The results show that the rubber particles reduce the strength and dry density of the FAR subgrade. And the basic mechanical properties of the subgrade can meet the requirements of railway engineering application when the rubber particle content does not exceed 15% of the mass of solid mixture. The damping ratio of the FAR subgrade increases linearly with the increase of the rubber particle content. And the smaller the rubber particle size is, the larger the damping ratio of the FAR subgrade will be. On this basis, it is recommended to use the rubber particles with particle size of 150 mesh and particle content no more than 15%. The new subgrade is recommended for subgrade filling below the surface layer of the subgrade bed. Compared with the ordinary subgrade, the dynamic stresses of the subgrade bed bottom layer, subgrade soil and foundation soil of the FAR subgrade are reduced by 10%− 30%. In the main frequency range of the FAR subgrade vibration, the ground vibration acceleration level is generally reduced by 2–6 dB and the reduction is up to 83 dB, which verifies the good vibration isolation performance of the new FAR subgrade.
•A new type of rubber particle-flowable fly ash (FAR) material was prepared.•The FAR material was applicable for the railway subgrade.•The FAR subgrade was of good vibration isolation performance.
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