The EDA/EDAR/NF-κB pathway in non-syndromic tooth agenesis: A genetic perspective

Non-syndromic tooth agenesis (NSTA) is one of the most common dental developmental malformations affected by genetic factors predominantly. Among all 36 candidate genes reported in NSTA individuals, EDA, EDAR, and EDARADD play essential roles in ectodermal organ development. As members of the EDA/EDAR/NF-κB signaling pathway, mutations in these genes have been implicated in the pathogenesis of NSTA, as well as hypohidrotic ectodermal dysplasia (HED), a rare genetic disorder that affects multiple ectodermal structures, including teeth. This review provides an overview of the current knowledge on the genetic basis of NSTA, with a focus on the pathogenic effects of the EDA/EDAR/NF-κB signaling pathway and the role of EDA, EDAR, and EDARADD mutations in developmental tooth defects. We also discuss the phenotypic overlap and genetic differences between NSTA and HED. Ultimately, this review highlights the importance of genetic analysis in diagnosing and managing NSTA and related ectodermal disorders, and the need for ongoing research to improve our understanding of these conditions

Reciprocal facilitation between annual plants and burrowing crabs:Implications for the restoration of degraded saltmarshes

Increasing evidence shows that facilitative interactions between species play an essential role in coastal wetland ecosystems. However, there is a lack of understanding of how such interactions can be used for restoration purposes in saltmarsh ecosystems. We therefore studied the mechanisms of reciprocal facilitative interactions between native annual plants, Suaeda salsa, and burrowing crabs, Helice tientsinensis, in a middle-elevation saltmarsh (with generally high plant density and moderate tides) in the Yellow River Delta of China. We investigated the relationship between the densities of the plants and crab burrows in different seasons. Then, we tested whether and how saltmarsh plants and crabs indeed facilitate each other in a series of field and laboratory experiments. Finally, we applied the results by creating a field-scale artificial approach for microtopographic modification to restore a degraded saltmarsh. We found that the density of plant seedlings in spring was positively correlated with the density of crab burrows in the previous autumn; moreover, the density of crab burrows was correlated with the density of plants in summer. The concave-convex surface microtopography created by crabs promoted seed retention and seedling establishment of saltmarsh plants in winter and spring. These plants in turn facilitated crabs by inhibiting predators, providing food and reducing physical stresses for crabs in summer and autumn. The experimental removal of saltmarsh plants decreased crab burrow density, while both transplanting and simulating plants in bare patches promoted crabs. The microtopographic modification, inspired by our new understanding of the interactions between saltmarsh plants and crabs, showed that these degraded saltmarsh ecosystems can be restored by a single ploughing intervention. Synthesis. Our results suggest a reciprocal facilitation between annual plants and burrowing crabs in a middle-elevation saltmarsh ecosystem. This knowledge yielded new restoration options for degraded coastal saltmarshes through the one-time ploughing initiation of microtopographic variation, which could promote the re-establishment of ecosystem engineers and lead to the efficient recovery of pioneer coastal vegetation and associated fauna

The Effect of Chemically Modified Multi-Walled Carbon Nanotubes on the Electro-Optical Properties of a Twisted Nematic Liquid Crystal Display Mode

In this study, we have chemically modified multi-walled carbon nanotubes (MWNTs) with different side chains for better dispersion in liquid crystal solutions, and fabricated twisted nematic liquid crystal cells doped with such MWNT derivatives. The introduction of MWNT derivatives affects the alignment of LC molecules with or without external electric fields. Electro-optical property tests showed that the contrast ratio changed slightly with the sharp decrease in drive voltage, improving the drive ability of the twisted nematic liquid crystal display (TN-LCD) mode

Side-Chain Liquid Crystal Co-Polymers for Angular Photochromic Anti-Counterfeiting Powder and Fiber

Anti-counterfeiting technologies with the features of easy distinguishability, high cost performance, and good processability are needed to meet the demands of a market during the consumption upgrading moment. A series of side-chain liquid crystal co-polymers (SCLCPs) are designed, synthesized, and blended, and the preparation of a series of angular photochromic materials that have different center reflection wavelengths in the visible and near infra-red region is reported in this article. Differential scanning calorimetry and polarized optical microscopy were utilized to characterize the phase transition behaviors and self-assembling structures of the SCLCPs. The selective reflection properties were characterized with a UV/VIS/IR spectrum study and further verified by scanning electron microscopy. The results showed that the SCLCPs had the desired reflection wavelengths and thermal stability. The SCLCPs could easily form a planar texture of cholesteric liquid crystal and, depending on the good processability, anti-counterfeiting powders and fibers with angular photochromic features were prepared and characterized to prove the potential applications of the SCLCPs in anti-counterfeiting labels

Angular Photochromic LC Composite Film for an Anti-Counterfeiting Label

In the harsh application environment, improving the mechanical properties of liquid crystal materials is a fundamental and important problem in the design of anti-counterfeit materials. In this paper, by a stepwise polymerization of first, photo-polymerization and subsequently thermal-polymerization, a coexistent polymer dispersed network was first constructed in cholesteric liquid crystal materials containing a photo-polymerizable system of urethane acrylate and a thermo-polymerizable system of isocyanate. Results revealed that the coexistent polymer dispersed network exhibited largely enhanced mechanical performance, and the networks obtained by different methods had different contributions to the enhancement of the peel strength and toughness of the composite films. Then an angular photochromic anti-fake label based on a coexistent polymer dispersed network with enhanced mechanical and apparent angular discoloration characteristics, suitable for practical applications, was successfully achieved

Polysiloxane-Based Side Chain Liquid Crystal Polymers: From Synthesis to Structure–Phase Transition Behavior Relationships

Organosilicon polymer materials play an important role in certain applications due to characteristics of much lower glass transition temperatures (Tg), viscosities, surface energy, as well as good mechanical, thermal stabilities, and insulation performance stemming from the higher bond energy and the larger bond angles of the adjacent silicon-oxygen bond. This critical review highlights developments in the synthesis, structure, and phase transition behaviors of polysiloxane-based side chain liquid crystal polymers (PSCLCPs) of linear and cyclic polysiloxanes containing homopolymers and copolymers. Detailed synthetic strategies are elaborated, and the relationship between molecular structures and liquid crystalline phase transition behaviors is systematically discussed, providing theoretical guidance on the molecular design of the materials

Effect of Liquid Crystalline Acrylates on the Electro-Optical Properties and Micro-Structures of Polymer-Dispersed Liquid Crystal Films

Polymer-dispersed liquid-crystal (PDLC) films have wide applications in light shutters, smart windows for cars and buildings, dimming glasses, and smart peep-proof films due to their switchable optical states under electrical fields as well as large area processibility. They are usually prepared with liquid crystals (LCs) and non-liquid crystalline monomers (NLCMs). Introduction of liquid crystalline monomers (LCMs) into PDLCs might spark new functionality or high-performance devices such as polymer-dispersed and -stabilized liquid crystals. In this study, the effect of molecular structures and doping concentrations of acrylate LCMs on the electro-optical properties and micro-structures of PDLC films is systematically studied. The pore size of polymer networks and the driving voltage of the PDLC films are affected by the molecular polarity and degree of functionality of the LCMs. The electro-optical properties of the PDLC films are affected by the synergistic influence of molecular structure of LCMs and micro-structures of PDLCs. These results might provide the experimental and theoretical basis for constructing the relationship between the molecular structure of LCM, micro-structure and electro-optical response of PDLC films

Colored PDLC Films with Wide Gamut Range

Due to the discoloration properties under different applied voltages, dye-doped polymer-dispersed liquid crystal (PDLC) films are widely used as camouflage nets and invisibility cloaks. However, the range of the discoloration has an intuitive effect on their applications. In this work, we studied the gamut range of PDLC film doped with dyes of red, green, blue, and yellow, with the concentration corresponding to the minimum haze of these dyes. The influence of the applied voltage on the color range of single-layer and double-layer films with different backgrounds was studied. The relationship of the voltage with the color was set from 0 V to 60 V at steps of 5 V, to characterize the discoloration of the PDLC films. The results showed that the films could cover 42.48% of the sRGB gamut and even exceed the range

Coupling of Defect Modes in Cholesteric Liquid Crystals Separated by Isotropic Polymeric Layers

Cholesteric liquid crystal structures with multiple isotropic defect layers exhibit localized optical modes (defect modes). Coupling effects between these modes were simulated using the finite difference time domain method. Analogous to the well-known result of the tight-binding approximation in solid state physics, splitting of the defect modes takes place, as soon as the structure contains more than one defect layer. The dispersion relation of the mini-bands forming within the photonic band gap of the structure is calculated numerically. The structures might have promising applications for multiwavelength filters and low-threshold lasers

Effect of Curing Temperature on the Properties of Electrically Controlled Dimming Film with Wide Working Temperature Range

In this paper, a polymer dispersed liquid crystal (PDLC) film with good electro-optical properties and wide working temperature range was prepared by the UV-polymerization induced phase separation (PIPS) method by optimizing the curing temperature using a LC with wide temperature range. The investigation found that when the polymerization temperature was at the clearing point of the prepolymer/LC mixture, the film had better electro-optical properties and a high contrast ratio of 51 at 90 °C, and the rise time and decay time were respectively as fast as 241.5 ms and 1750 ms at −20 °C. This study provides further methodological guidance for the curing process of PDLC film, and promotes its application in outdoor smart windows