MicroRNA396 negatively regulates shoot regeneration in tomato.

Numerous studies have been dedicated to genetically engineering crops to enhance their yield and quality. One of the key requirements for generating genetically modified plants is the reprogramming of cell fate. However, the efficiency of shoot regeneration during this process is highly dependent on genotypes, and the underlying molecular mechanisms remain poorly understood. Here, we identified microRNA396 (miR396) as a negative regulator of shoot regeneration in tomato. By selecting two genotypes with contrasting shoot regeneration efficiencies and analyzing their transcriptome profiles, we found that miR396 and its target transcripts, which encode GROWTH-REGULATING FACTORs (GRFs), exhibit differential abundance between high- and low-efficiency genotypes. Suppression of miR396 functions significantly improved shoot regeneration rates along with increased expression of GRFs in transformed T0 explants, suggesting that miR396 is a key molecule involved in the determination of regeneration efficiency. Notably, we also showed that co-expression of a miR396 suppressor with the gene-editing tool can be employed to generate gene-edited plants in the genotype with a low capacity for shoot regeneration. Our findings show the critical role of miR396 as a molecular barrier to shoot regeneration in tomato and suggest that regeneration efficiency can be improved by blocking this single microRNA.

Cortical Iron Accumulation as an Imaging Marker for Neurodegeneration in Clinical Cognitive Impairment Spectrum: A Quantitative Susceptibility Mapping Study.

OBJECTIVE: Cortical iron deposition has recently been shown to occur in Alzheimer's disease (AD). In this study, we aimed to evaluate how cortical gray matter iron, measured using quantitative susceptibility mapping (QSM), differs in the clinical cognitive impairment spectrum. MATERIALS AND METHODS: This retrospective study evaluated 73 participants (mean age ± standard deviation, 66.7 ± 7.6 years; 52 females and 21 males) with normal cognition (NC), 158 patients with mild cognitive impairment (MCI), and 48 patients with AD dementia. The participants underwent brain magnetic resonance imaging using a three-dimensional multi-dynamic multi-echo sequence on a 3-T scanner. We employed a deep neural network (QSMnet+) and used automatic segmentation software based on FreeSurfer v6.0 to extract anatomical labels and volumes of interest in the cortex. We used analysis of covariance to investigate the differences in susceptibility among the clinical diagnostic groups in each brain region. Multivariable linear regression analysis was performed to study the association between susceptibility values and cognitive scores including the Mini-Mental State Examination (MMSE). RESULTS: Among the three groups, the frontal (P < 0.001), temporal (P = 0.004), parietal (P = 0.001), occipital (P < 0.001), and cingulate cortices (P < 0.001) showed a higher mean susceptibility in patients with MCI and AD than in NC subjects. In the combined MCI and AD group, the mean susceptibility in the cingulate cortex (ß = -216.21, P = 0.019) and insular cortex (ß = -276.65, P = 0.001) were significant independent predictors of MMSE scores after correcting for age, sex, education, regional volume, and APOE4 carrier status. CONCLUSION: Iron deposition in the cortex, as measured by QSMnet+, was higher in patients with AD and MCI than in NC participants. Iron deposition in the cingulate and insular cortices may be an early imaging marker of cognitive impairment related neurodegeneration.

Data-Driven Object Vehicle Estimation by Radar Accuracy Modeling with Weighted Interpolation.

For accurate object vehicle estimation using radar, there are two fundamental problems: measurement uncertainties in calculating an object's position with a virtual polygon box and latency due to commercial radar tracking algorithms. We present a data-driven object vehicle estimation scheme to solve measurement uncertainty and latency problems in radar systems. A radar accuracy model and latency coordination are proposed to reduce the tracking error. We first design data-driven radar accuracy models to improve the accuracy of estimation determined by the object vehicle's position. The proposed model solves the measurement uncertainty problem within a feasible set for error covariance. The latency coordination is developed by analyzing the position error according to the relative velocity. The position error by latency is stored in a feasible set for relative velocity, and the solution is calculated from the given relative velocity. Removing the measurement uncertainty and latency of the radar system allows for a weighted interpolation to be applied to estimate the position of the object vehicle. Our method is tested by a scenario-based estimation experiment to validate the usefulness of the proposed data-driven object vehicle estimation scheme. We confirm that the proposed estimation method produces improved performance over the conventional radar estimation and previous methods.

In Vitro and In Vivo Biosafety Analysis of Resorbable Polyglycolic Acid-Polylactic Acid Block Copolymer Composites for Spinal Fixation.

Herein, spinal fixation implants were constructed using degradable polymeric materials such as PGA-PLA block copolymers (poly(glycolic acid-b-lactic acid)). These materials were reinforced by blending with HA-g-PLA (hydroxyapatite-graft-poly lactic acid) and PGA fiber before being tested to confirm its biocompatibility via in vitro (MTT assay) and in vivo animal experiments (i.e., skin sensitization, intradermal intracutaneous reaction, and in vivo degradation tests). Every specimen exhibited suitable biocompatibility and biodegradability for use as resorbable spinal fixation materials.

A graphene barristor using nitrogen profile controlled ZnO Schottky contacts.

We have successfully demonstrated a graphene-ZnO:N Schottky barristor. The barrier height between graphene and ZnO:N could be modulated by a buried gate electrode in the range of 0.5-0.73 eV, and an on-off ratio of up to 107 was achieved. By using a nitrogen-doped ZnO film as a Schottky contact material, the stability problem of previously reported graphene barristors could be greatly alleviated and a facile route to build a top-down processed graphene barristor was realized with a very low heat cycle. This device will be instrumental when implementing logic functions in systems requiring high-performance logic devices fabricated with a low temperature fabrication process such as back-end integrated logic devices or flexible devices on soft substrates.

Alloyed 2D Metal-Semiconductor Heterojunctions: Origin of Interface States Reduction and Schottky Barrier Lowering.

The long-term stability and superior device reliability through the use of delicately designed metal contacts with two-dimensional (2D) atomic-scale semiconductors are considered one of the critical issues related to practical 2D-based electronic components. Here, we investigate the origin of the improved contact properties of alloyed 2D metal-semiconductor heterojunctions. 2D WSe2-based transistors with mixed transition layers containing van der Waals (M-vdW, NbSe2/WxNb1-xSe2/WSe2) junctions realize atomically sharp interfaces, exhibiting long hot-carrier lifetimes of approximately 75,296 s (78 times longer than that of metal-semiconductor, Pd/WSe2 junctions). Such dramatic lifetime enhancement in M-vdW-junctioned devices is attributed to the synergistic effects arising from the significant reduction in the number of defects and the Schottky barrier lowering at the interface. Formation of a controllable mixed-composition alloyed layer on the 2D active channel would be a breakthrough approach to maximize the electrical reliability of 2D nanomaterial-based electronic applications.

Ferroelectric/Dielectric Double Gate Insulator Spin-Coated Using Barium Titanate Nanocrystals for an Indium Oxide Nanocrystal-Based Thin-Film Transistor.

Barium titanate nanocrystals (BT NCs) were prepared under solvothermal conditions at 200 °C for 24 h. The shape of the BT NCs was tuned from nanodot to nanocube upon changing the polarity of the alcohol solvent, varying the nanosize in the range of 14-22 nm. Oleic acid-passivated NCs showed good solubility in a nonpolar solvent. The effect of size and shape of the BT NCs on the ferroelectric properties was also studied. The maximum polarization value of 7.2 µC/cm(2) was obtained for the BT-5 NC thin film. Dielectric measurements of the films showed comparable dielectric constant values of BT NCs over 1-100 kHz without significant loss. Furthermore, the bottom gate In2O3 NC thin film transistors exhibited outstanding device performance with a field-effect mobility of 11.1 cm(2) V(-1) s(-1) at a low applied gate voltage with BT-5 NC/SiO2 as the gate dielectric. The low-density trapped state was observed at the interface between the In2O3 NC semiconductor and the BT-5 NCs/SiO2 dielectric film. Furthermore, compensation of the applied gate field by an electric dipole-induced dipole field within the BT-5 NC film was also observed.

Characteristics of a pressure sensitive touch sensor using a piezoelectric PVDF-TrFE/MoS2 stack.

A new touch sensor device has been demonstrated with molybdenum disulfide (MoS2) field effect transistors stacked with a piezoelectric polymer, polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE). The performance of two device stack structures, metal/PVDF-TrFE/MoS2 (MPM) and metal/PVDF-TrFE/Al2O3/MoS2 (MPAM), were compared as a function of the thickness of PVDF-TrFE and Al2O3. The sensitivity of the touch sensor has been improved by two orders of magnitude by reducing the charge scattering and enhancing the passivation effects using a thin Al2O3 interfacial layer. Reliable switching behavior has been demonstrated up to 120 touch press cycles.

Ferroelectric polymer-gated graphene memory with high speed conductivity modulation.

The feasibility of a high speed ferroelectric graphene memory device using a ferroelectric polymer (PVDF-TrFE)/graphene stack has been demonstrated. The conductivity of this metal-ferroelectric-graphene (MFG) device could be modulated up to 775% with a very fast programming speed down to 10 ns. Also, programmed states were maintained up to 1000 s with endurance over 1000 cycles. In addition to demonstrating a single memory device, the array-level integration and cell write/read functionality of a 4 × 4 MFG array adopting a graphene bit line has also been confirmed to show the feasibility of MFG memory.