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• Top-gate TFTs with PPD-prepared ZnSnO channel layers have been fabricated. • The property of TFTs can be controllable by adjusting channel-layer structure. • The fabricated double-channel-layer ZnSnO TFT exhibits excellent performance. In this study, an inorganic–organic hybrid thin-film transistor (TFT) with a top-gate structure is prepared using an inorganic ZnSnO film prepared via pulse plasma deposition as the channel layer and an organic polymethyl methacrylate film prepared by the solution method as the dielectric layer. The effect of oxygen pressure during the preparation of the ZnSnO channel layer and channel-layer structure on ZnSnO TFT performance was studied. The results show that increasing the oxygen pressure during the preparation process can effectively inhibit the formation of oxygen vacancies in ZnSnO and reduce the concentration of electron carriers in ZnSnO, resulting in a reduced off current and a positive shift of the threshold voltage (V th) in the single-channel layer ZnSnO TFT. In addition, a high-resistivity ZnSnO layer (Lt; with a lower electron-carrier concentration) is embedded between the low-resistivity ZnSnO layer (Lb; with a higher electron-carrier concentration) and the dielectric layer to form a high-/low-resistivity double-channel-layer structure (Lt/Lb). By changing the thickness combination of Lt/Lb, the resistance of the channel layer and the number of carriers modulated by gate voltage in the channel layer can be optimized, thereby adjusting the device's on current (affecting device mobility) and key energy consumption parameters (i.e., V th and off current) to achieve independent control. Thus, the fabricated double-channel-layer ZnSnO TFT exhibits excellent performance: high mobility (3.28 cm2/Vs), positive V th close to 0 V (0.48 V), and on-to-off current ratio of > 105. [ABSTRACT FROM AUTHOR]

Mg alloys possess biodegradability, suitable mechanical properties, and biocompatibility, which make them possible to be used as biodegradable implants. However, the uncontrollable degradation of Mg alloys limits their general applications. In addition to the factors from the metallic materials themselves, like alloy compositions, heat treatment process and microstructure, some external factors, relating to the test/service environment, also affect the degradation rate of Mg alloys, such as inorganic salts, bioorganic small molecules, bioorganic macromolecules. The influence of bioorganic molecules on Mg corrosion and its protection has attracted more and more attentions. In this work, the cutting-edge advances in the influence of bioorganic molecules (i.e., protein, glucose, amino acids, vitamins and polypeptide) and their coupling effect on Mg degradation and the formation of protection coatings were reviewed. The research orientations of biomedical Mg alloys in exploring degradation mechanisms in vitro were proposed, and the impact of bioorganic molecules on the protective approaches were also explored. [ABSTRACT FROM AUTHOR]

This prospective study analyzed changes in the oral and intestinal microbiomes in patients before and after fixed orthodontic treatment, elucidating the impacts of fixed orthodontic treatment on patient health and metabolism. Metagenomic analysis was conducted on stool, dental plaque, and saliva samples from 10 fixed orthodontic patients. All the samples were sequenced with Illumina NovaSeq 6000 with a paired-end sequencing length of 150 bp. Identification of taxa in metagenomes and functional annotation of genes of the microbiota were performed using the data after quality control. Clinical periodontal parameters, including the gingiva index, plaque index, and pocket probing depth, were examined at each time point in triplicates. Patients also received a table to record their oral hygiene habits of brushing, flossing, and dessert consumption frequency over 1 month. The brushing and flossing times per day of patients were significantly increased after treatment compared with baseline. The number of times a patient ate dessert daily was also fewer after treatment than at baseline. In addition, the plaque index decreased significantly, whereas the pH value of saliva, gingiva index, and pocket probing depth did not change. No significant differences were observed between the participants before and after orthodontic treatment regarding alpha-diversity analysis of the gut, dental plaque, or saliva microbiota. However, on closer analysis, periodontal disease-associated bacteria levels in the oral cavity remain elevated. Alterations in gut microbiota were also observed after orthodontic treatment. The richness and diversity of the microbiome did not change significantly during the initial stage of fixed orthodontic treatment. However, the levels of periodontal disease-associated bacteria increased. • Good oral hygiene did not prevent periodontal bacteria rise during orthodontic start. • First metagenomic study on post-orthodontic gut microbiota changes. • Twenty-two gut microbiota taxa increased significantly after orthodontic treatment. [ABSTRACT FROM AUTHOR]

Brain mapping is fundamental to understanding brain organization and function. However, a major drawback to the traditional Brodmann parcellation technique is the reliance on the use of postmortem specimens. It has therefore historically been difficult to make any comparison regarding functional data from different regions or hemispheres within the same individual. Moreover, this method has been significant limited by subjective boundaries and classification criteria and therefore suffer from reproducibility issues. The development of transcranial magnetic stimulation (TMS) offers an alternative approach to brain mapping, specifically the motor cortical regions by eliciting quantifiable functional reactions. To precisely describe the motor cortical topographic representation of pharyngeal constrictor musculature using TMS and to further map the brain for use as a tool to study brain plasticity. 51 healthy subjects (20 male/31 female, 19–26 years old) were tested using single-pulse TMS combined with intraluminal catheter-guided high-resolution manometry and a standardized grid cap. We investigated various parameters of the motor-evoked potential (MEP) that include the motor map area, amplitude, latency, center of gravity (CoG) and asymmetry index. Cortically evoked response latencies were similar for the left and right hemispheres at 6.79 ± 0.22 and 7.24 ± 0.27 ms, respectively. The average scalp positions (relative to the vertex) of the pharyngeal motor cortical representation were 10.40 ± 0.19 (SE) cm medio-lateral and 3.20 ± 0.20 (SE) cm antero-posterior in the left hemisphere and 9.65 ± 0.24 (SE) cm medio-lateral and 3.18 ± 0.23 (SE) cm antero-posterior in the right hemisphere. The mean motor map area of the pharynx in the left and right hemispheres were 9.22 ± 0.85(SE) cm2and 10.12 ± 1.24(SE) cm2, respectively. The amplitudes of the MEPs were 35.94 ± 1.81(SE)uV in the left hemisphere and 34.49 ± 1.95(SE)uV in the right hemisphere. By comparison, subtle but consistent differences in the degree of the bilateral hemispheric representation were also apparent both between and within individuals. The swallowing musculature has a bilateral motor cortical representation across individuals, but is largely asymmetric within single subjects. These results suggest that TMS mapping using a guided intra-pharyngeal EMG catheter combined with a standardized gridded cap might be a useful tool to localize brain function/dysfunction by linking brain activation to the corresponding physical reaction. • High-resolution Manometry was used firstly to test the length from nostril to pharyngeal musculature. • The approach allows precise insertion of intraluminal catheter and electrodes for PMEP measurement. • We created a standard gripped scalp cap for TMS mapping procedure. • A larger sample size had been recruited. [ABSTRACT FROM AUTHOR]

A Zinc-loaded montmorillonite (Zn-MMT) coating was hydrothermally prepared using Zn2+ ion intercalated sodium montmorillonite (Na-MMT) upon magnesium (Mg) alloy AZ31 as bone repairing materials. Biodegradation rate of the Mg-based materials was studied via potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS) and hydrogen evolution tests. Results revealed that both Na-MMT and Zn-MMT coatings exhibited better corrosion resistance in Dulbecco's modified eagle medium (DMEM) + 10% calf serum (CS) than bare Mg alloy AZ31 counterparts. Hemolysis results demonstrated that hemocompatibility of the Na-MMT and Zn-MMT coatings were 5%, and lower than that of uncoated Mg alloy AZ31 pieces. In vitro MTT tests and live-dead stain of osteoblast cells (MC3T3-E1) indicated a significant improvement in cytocompatibility of both Na-MMT and Zn-MMT coatings. Antibacterial properties of two representative bacterial strains associated with device-related infection, i.e. Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), were employed to explore the antibacterial behavior of the coatings. The measured inhibitory zone and bacterial growth rate confirmed that Zn-MMT coatings exhibited higher suppression toward both E. coli and S. aureus than that of Na-MMT coatings. The investigation on antibacterial mechanism through scanning electron microscopy (SEM) and lactate dehydrogenase (LDH) release assay manifested that Zn-MMT coating led to severe breakage of bacterial membrane of E. coli and S. aureus , which resulted in a release of cytoplasmic materials from the bacterial cells. In addition, the good inhibition of Zn-MMT coatings against E. coli and S. aureus might be attributed to the slow but sustainable release of Zn2+ ions (up to 144 h) from the coatings into the culture media. This study provides a novel coating strategy for manufacturing biodegradable Mg alloys with good corrosion resistance, biocompatibility and antibacterial activity for future orthopedic applications. The significance of the current work is to develop a corrosion-resistant and antibacterial Zn-MMT coating on magnesium alloy AZ31 through a hydrothermal method. The Zn-MMT coating on magnesium alloy AZ31 shows better corrosion resistance, biocompatibility and excellent antibacterial ability than magnesium alloy AZ31. This study provides a novel coating on Mg alloys for future orthopedic applications. [ABSTRACT FROM AUTHOR]

The karyotypes of Tulipa sinkiangensis and T. schrenkii were analyzed based on chromosome size and the physical mapping of 5S and 45S ribosomal DNAs (rDNAs) using fluorescence in situ hybridization. The genomes from both species were consistent with the uniform karyotype formula, i.e., having four pairs of submedian and eight pairs of subterminal chromosomes (2 n =2 x =24=8sm+16st). Remarkably, the number and location of 5S rDNA loci were quite different between the two species. A single pair of 5S rDNA loci was detected on both chromosomes 5 in T. sinkiangensis , but the 5S rDNA loci were detected on almost all chromosomes in T. schrenkii , except for chromosomes 4 and 6. For both species, the 45S rDNA loci were localized to telomeric regions of the chromosome—on either the short or long arm. Interestingly, the 5S rDNA and 45S rDNA loci positions and numbers varied among different genotypes of T. schrenkii . We conclude that the two species are close relatives and that a series of genome modifications occurred during the diversification of these two species. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Magnesium (Mg) and its alloys have become a research frontier in biodegradable materials owing to their superior biocompatibility and excellent biomechanical compatibility. However, their high degradation rate in the physiological environment should be well tackled prior to clinical applications. This review summarizes the latest progress in the development of polymeric coatings on biodegradable Mg alloys over the last decade, regarding preparation strategies for polylactic acid (PLA), poly (latic-co-glycolic) acid (PLGA), polycaprolactone (PCL), polydopamine (PDA), chitosan (CS), collagen (Col) and their composite, and their performance in terms of corrosion resistance and biocompatibility. Feasible perspectives and developing directions of next generation of polymeric coatings with respect to biomedical Mg alloys are briefly discussed. Statement of Significance Magnesium (Mg) and its alloys have become a research frontier in biodegradable materials owing to their superior biocompatibility and suitable biomechanical compatibility. However, the principal drawback of Mg-based implants is their poor corrosion resistance in physiological environments. Hence, it is vital to mitigate the degradation/corrosion behavior of Mg alloys for safe biomedical deployments. This review summarizes the latest progress in development of polymeric coatings on biomedical Mg alloys regarding preparation strategy, corrosion resistance and biocompatibility, including polylactic acid (PLA), poly (latic-co-glycolic) acid (PLGA), polycaprolactone (PCL), chitosan (CS), polydopamine (PDA), collagen (Col) and their composite. In addition, functionalized polymer coatings with Mg alloys exhibits a promising prospect owing to their ability of degradation along with biocompatibility, self-healing, drug-delivery and osteoinduction. [ABSTRACT FROM AUTHOR]