Not Just a Simple Sugar: Arabinose Metabolism and Function in Plants.

Growth, development, structure as well as dynamic adaptations and remodeling processes in plants are largely controlled by properties of their cell walls. These intricate wall structures are mostly made up of different sugars connected through specific glycosidic linkages but also contain many glycosylated proteins. A key plant sugar that is present throughout the plantae, even before the divergence of the land plant lineage, but is not found in animals, is l-arabinose (l-Ara). Here, we summarize and discuss the processes and proteins involved in l-Ara de novo synthesis, l-Ara interconversion, and the assembly and recycling of l-Ara-containing cell wall polymers and proteins. We also discuss the biological function of l-Ara in a context-focused manner, mainly addressing cell wall-related functions that are conferred by the basic physical properties of arabinose-containing polymers/compounds. In this article we explore these processes with the goal of directing future research efforts to the many exciting yet unanswered questions in this research area.

Safety and efficacy of basic fibroblast growth factors for deep second-degree burn patients.

INTRODUCTION: Burn injuries are common afflictions; however, conservative wound care frequently leads to poor treatment compliance and physical disability in deep burn patients. Therefore, regenerative biologic materials, which are more effective for tissue repair, are required, particularly for deep second-degree burns. A novel spray formulation of basic fibroblast growth factors (bFGF) was produced by synthesizing fibroblast growth factor proteins. In this post-marketing surveillance (PMS) study, we assessed the safety and efficacy of bFGF and indirectly compared this formulation with cultured epidermal autografts (CEAs) for treating deep second-degree burns. MATERIALS AND METHODS: A total of 3173 patients treated at 15 hospitals were used for PMS of bFGF in South Korea for six years. In total, 1630 patients with deep second-degree burns were selected for assessing adverse events (AEs) of bFGF treatments. Efficacy was evaluated according to time periods until re-epithelialization, and clinical usefulness of bFGF was indirectly compared with that of CEAs. RESULTS: AEs occurred in 37 patients (2.3%) and included application site pain (1.7%) and contact dermatitis (0.6%). All AEs were mild and were evaluated as probably unrelated with bFGF. The average time for re-epithelialization was 8 days; this time span was significantly longer after major burns (9.7 days) than after minor (7.8 days) or moderate burns (7.9 days). Most treated burn wounds (99.8%) were assessed as improved. The indirect comparison included 534 patients using the same inclusion criteria for CEA patients (n = 35). The bFGF treatment demonstrated superior efficacy compared to CEAs by significantly reducing the average day to application (5.4 vs. 8.8 days) and re-epithelialization time (7.1 vs. 13.7 days). CONCLUSION: Our study demonstrated that bFGF is a compelling regenerative therapy with competitive clinical efficacy and safety for deep second-degree burns and reduced treatment time, which is expected to reduce medical costs, particularly for deep second-degree burn patients.

Performance of AlGaN/GaN Nanowire Omega-Shaped-Gate Fin-Shaped Field-Effect Transistor.

The AlGaN/GaN nanowire omega-shaped-gate FinFET have been successfully fabricated demonstrating much improved performance compared to conventional AlGaN/GaN MISHFET. The AlGaN/GaN omega-shaped-gate FinFET exhibited the remarkable on-state performances, such as maximum drain current of 1.1 A/mm, low on-resistance, and low current collapse compared to that of the conventional device structure. In addition, the excellent off-state performances were measured: low off-state leakage current as low as -10(-10) mA, the theoretical SS value of -62 mV/dec, and high I(ON)/I(OFF) ratio (-10(9)). Improved dc performances were obtained for omega-shaped-gate structure due to the fully depletion of the active fin body and perfectly separation of the depleted fin from the underlying thick GaN buffer layer. Furthermore, the additional reason for the enhanced device performance of the proposed device is the improved gate controllability compared to the conventional MISHFET. The proposed nano-structure device is very promising candidate for the steep switching device applications.

Short-Channel Tunneling Field-Effect Transistor with Drain-Overlap and Dual-Metal Gate Structure for Low-Power and High-Speed Operations.

We have investigated and proposed a highly scaled tunneling field-effect transistor (TFET) based on Ge/GaAs heterojunction with a drain overlap to suppress drain-induced barrier thinning (DIBT) and improve low-power (LP) performance. The highly scaled TFET with a drain overlap achieves lower leakage tunneling current because of the decrease in tunneling events between the source and drain, whereas a typical short-channel TFET suffers from a great deal of tunneling leakage current due to the DIBT at the off-state. However, the drain overlap inevitably increases the gate-to-drain capacitance (Cgd) because of the increase in the overlap capacitance (Cov) and inversion capacitance (Cinv). Thus, in this work, a dual-metal gate structure is additionally applied along with the drain overlap. The current performance and the total gate capacitance (Cgg) of the device with a dual-metal gate can be possibly controlled by adjusting the metal gate workfunction (φgate) and φoverlap-gate in the overlapping regions. As a result, the intrinsic delay time (τ) is greatly reduced by obtaining lower Cgg divided by the on-state current (Ion), i.e., Cgg/Ion. We have successfully demonstrated excellent LP and high-speed performance of a highly scaled TFET by adopting both drain overlap and dual-metal gate with DIBT minimization.