Secondary caries caused by dental plaque is one of the major reasons for the high failure rate of resin composite restoration. Although antimicrobial agent–modified dental restoration systems have ...been researched for years, few reported intelligent anticaries materials could respond to the change of the oral environment and help keep oral eubiosis. Herein, we report tertiary amine (TA)–modified resin adhesives (TA@RAs) with pH-responsive antibacterial effect to reduce the occurrence of secondary caries. Two kinds of newly designed TA monomers were synthesized: DMAEM (dodecylmethylaminoethyl methacrylate) and HMAEM (hexadecylmethylaminoethyl methacrylate). In the minimum inhibitory concentration and minimum bactericidal concentration test against Streptococcus mutans, Streptococcus sanguinis, and Streptococcus gordonii, they exhibited antibacterial effect only in acidic medium, which preliminarily verified the acid-activated effect of TAs. Then DMAEM and HMAEM were incorporated into adhesive resin at the mass fraction of 5%, yielding TA@RAs. In vivo and in vitro tests showed that the mechanical properties and biocompatibility of the adhesive were not affected. A S. mutans biofilm model in acidic and neutral medium was used and confirmed that TA@RAs could respond to the critical pH value of de-/remineralization and acquire reversible antibiofilm effect via the protonation and deprotonation of TAs. Meanwhile, the stability of antibacterial effect was confirmed via a 5-d pH-cycling experiment and a saliva-derived biofilm aging model. Furthermore, 16S rRNA gene sequencing showed that TA@RAs could increase the diversity of the saliva-derived biofilms, which implied that the novel materials could help regulate the microbial community to a healthy one. Finally, an in vitro demineralization model and in vivo secondary caries model were applied and demonstrated that TA@RAs could prevent secondary dental caries effectively. In summary, the reversible pH-responsive and non–drug release antibacterial resin adhesives ingeniously overcome the defect of the present materials and hold great promise for clinical application.
Recent genome-wide association studies identified over 100 genetic loci that significantly associate with schizophrenia (SZ). A top candidate gene, ZNF804A, was robustly replicated in different ...populations. However, its neural functions are largely unknown. Here we show in mouse that ZFP804A, the homolog of ZNF804A, is required for normal progenitor proliferation and neuronal migration. Using a yeast two-hybrid genome-wide screen, we identified novel interacting proteins of ZNF804A. Rather than transcriptional factors, genes involved in mRNA translation are highly represented in our interactome result. ZNF804A co-fractionates with translational machinery and modulates the translational efficiency as well as the mTOR pathway. The ribosomal protein RPSA interacts with ZNF804A and rescues the migration and translational defects caused by ZNF804A knockdown. RNA immunoprecipitation-RNAseq (RIP-Seq) identified transcripts bound to ZFP804A. Consistently, ZFP804A associates with many short transcripts involved in translational and mitochondrial regulation. Moreover, among the transcripts associated with ZFP804A, a SZ risk gene, neurogranin (NRGN), is one of ZFP804A targets. Interestingly, downregulation of ZFP804A decreases NRGN expression and overexpression of NRGN can ameliorate ZFP804A-mediated migration defect. To verify the downstream targets of ZNF804A, a Duolink in situ interaction assay confirmed genes from our RIP-Seq data as the ZNF804A targets. Thus, our work uncovered a novel mechanistic link of a SZ risk gene to neurodevelopment and translational control. The interactome-driven approach here is an effective way for translating genome-wide association findings into novel biological insights of human diseases.
To examine the influence of clay minerals on methane adsorption in shales, shale samples with low total organic carbon (TOC), ranging from 0.23 to 3.2 wt%, were collected from the Canning and Perth ...basins, Western Australia. The collected shale samples were measured on gas adsorption experiments: high-pressure methane adsorption and low-pressure nitrogen and carbon dioxide adsorption. Geological controlling factors of methane adsorption capacity for the studied samples were analysed based on a classification of TOC: low-TOC (<1.5 wt%) and high-TOC (>1.5 wt%) samples. The results show that the contribution of organic matter to the methane adsorption capacity of the studied samples is limited. The clay content appears to have a good relationship with the methane adsorption capacity, especially for the low-TOC (<1.5 wt%) samples, which is also supported by the Brunauer-Emmett-Teller surface area. TOC-normalised methane adsorption capacity decreases with increasing thermal maturity for the high-TOC (>1.5 wt%) samples. Furthermore, adsorption affinity of methane, described by the reciprocal of Langmuir pressure, is positively related to the micropore volume and T
max
for the high-TOC samples (>1.5 wt%).
(1) A weak relationship exists between TOC and methane adsorption capacity and clay minerals dominate methane adsorption capacity for low TOC (<1.5 wt%) shale samples.
(2) Methane adsorption capacity per wt% TOC decreases with increasing thermal maturity for high TOC samples and may result from changes in surface chemistry or roughness of pores.
(3) Affinity of adsorption for the high TOC samples is positively related to the micropore volume and thermal maturity.
Chemical and topological parameters have been widely used for predicting the phase selection in high-entropy alloys (HEAs). Nevertheless, previous studies could be faulted due to the small number of ...available data points, the negligence of kinetic effects, and the insensitivity to small compositional changes. Here in this work, 92 TiZrHfM, TiZrHfMM, TiZrHfMMM (M = Fe, Cr, V, Nb, Al, Ag, Cu, Ni) HEAs were prepared by melt spinning, to build a reliable and sufficiently large material database to inspect the robustness of previously established parameters. Modification of atomic radii by considering the change of local electronic environment in alloys, was critically found out to be superior in distinguishing the formation of amorphous and crystalline alloys, when compared to using atomic radii of pure elements in topological parameters. Moreover, crystal structures of alloying element were found to play an important role in the amorphous phase formation, which was then attributed to how alloying hexagonal-close-packed elements and face-centered-cubic or body-centered-cubic elements can affect the mixing enthalpy. Findings from this work not only provide parametric studies for HEAs with new and important perspectives, but also reveal possibly a hidden connection among some important concepts in various fields.
Background
The PA method combines optical absorption with acoustic detection of laser-generated ultrasound signals to enable high-resolution and high-speed imaging and determination of the mechanical ...properties of materials. A measurement of a single point takes only a few seconds; thus, the PA method is high throughput and allows for extracting spatially varying mechanical properties of materials, which is critical in characterizing heterogeneous materials such as biological tissues. As the PA method is non-contact, it precludes damaging the sample surfaces during the measurements.
Objective
This study explores the ability of a non-contact and high throughput photoacoustic (PA) method to extract the elastic moduli of bioenergy sorghum tissues, i.e., rind, pith, and vascular bundle, in the axial direction.
Methods
A pulsed laser generated a collimated circular beam, which was expanded from 3 mm to 15 mm by a pair of convex lenses. To increase the light absorption, red ink was applied to the sample surface. A focused laser beam from a vibrometer was also delivered at the same location to measure the local surface displacement in the vertical direction. The built-in camera of the vibrometer was used as a monitor.
Results
The elastic modulus of the bioenergy sorghum rind was significantly larger than the moduli of the pith and fiber bundles, thus indicating that rind tissues were much stiffer. The statistical results show statistically significant differences among the elastic moduli of the different tissues.
Conclusions
These measurements agree well with studies that have implemented other characterization techniques, thus attesting to the utility of the PA technique in characterizing sorghum and other plants going forward.
To eliminate the adverse impacts of hydrogen evolution on the capacity of iron-chromium redox flow batteries (ICRFBs) during the long-term operation and ensure the safe operation of the battery, a ...rebalance cell that reduces the excessive Fe(III) ions at the positive electrolyte by using the hydrogen evolved from the negative electrolyte is designed, fabricated and tested. The effects of the flow field, hydrogen concentration and H2/N2 mixture gas flow rate on the performance of the hydrogen-ferric ion rebalance cell have been investigated. Results show that: i) an interdigitated flow field based rebalance cell delivers higher limiting current densities than serpentine flow field based one does; ii) the hydrogen utilization can approach 100% at low hydrogen concentrations (≤5%); iii) the apparent exchange current density of hydrogen oxidation reaction in the rebalance cell is proportional to the square root of the hydrogen concentration at the hydrogen concentration from 1.3% to 50%; iv) a continuous rebalance process is demonstrated at the current density of 60 mA cm−2 and hydrogen concentration of 2.5%. Moreover, the cost analysis shows that the rebalance cell is just approximately 1% of an ICRFB system cost.
•The performance of the hydrogen-ferric ion rebalance cell is investigated.•Hydrogen utilization approaches 100% at low hydrogen percentages (≤5%).•A continuous rebalance is achieved at 60 mA cm−2 and 2.5% hydrogen percentage.•The rebalance cell is estimated to be approximately 1% of system cost.
Streptococcus mutans and Candida albicans are frequently co‐isolated from dental plaque of children with early childhood caries (ECC) and are only rarely found in children without ECC, suggesting ...that these species interact in a manner that contributes to the pathogenesis of ECC. Previous studies have demonstrated that glucans produced by S. mutans are crucial for promoting the formation of biofilm and cariogenicity with C. albicans; however, it is unclear how non‐glucan S. mutans biofilm factors contribute to increased biofilm formation in the presence of C. albicans. In this study we examined the role of S. mutans antigen I/II in two‐species biofilms with C. albicans, and determined that antigen I/II is important for the incorporation of C. albicans into the two‐species biofilm and is also required for increased acid production. The interaction is independent of the proteins Als1 and Als3, which are known streptococcal receptors of C. albicans. Moreover, antigen I/II is required for the colonization of both S. mutans and C. albicans during co‐infection of Drosophila melanogaster in vivo. Taken together, these results demonstrate that antigen I/II mediates the increase of C. albicans numbers and acid production in the two‐species biofilm, representing new activities associated with this known S. mutans adhesin.
Carbon nanomaterials-based electric double-layer capacitors (EDLCs) are reliable and appealing energy-storage systems offering high power density and long cycling stability. However, these energy ...storage devices are plagued with critical shortcomings, such as low specific capacitance, inefficient physical/chemical activation process, and self-discharge of electrode materials, hindering their future application. In this work, we use a self-activation process, an environmentally benign and low-cost process, to produce high-performance activated carbon (AC). Novel activated carbon from pecan shells (PS) was successfully synthesized through a single-step self-activation process, which combines the carbonization and activation processes. The as-synthesized pecan shell-derived activated carbon (PSAC) provides a high-porosity, low-resistance, and ordered pore structure with a specific pore volume of 0.744 cm3/g and BET surface area of 1554 m2/g. The supercapacitors fabricated from PSAC demonstrate a specific capacitance of 269 F/g at 2 A/g, excellent cycling stability over 15,000 cycles, and energy and power density of 37.4 Wh/kg and of 2.1 kW/kg, respectively. It is believed that the high-efficiency PSAC synthesized from the novel self-activation method could provide a practical route to environmentally friendly and easily scalable supercapacitors.
PDF
