Factors influencing the development of artificial intelligence in orthodontics.

OBJECTIVES: Since developing AI procedures demands significant computing resources and time, the implementation of a careful experimental design is essential. The purpose of this study was to investigate factors influencing the development of AI in orthodontics. MATERIALS AND METHODS: A total of 162 AI models were developed, with various combinations of sample sizes (170, 340, 679), input variables (40, 80, 160), output variables (38, 76, 154), training sessions (100, 500, 1000), and computer specifications (new vs. old). The TabNet deep-learning algorithm was used to develop these AI models, and leave-one-out cross-validation was applied in training. The goodness-of-fit of the regression models was compared using the adjusted coefficient of determination values, and the best-fit model was selected accordingly. Multiple linear regression analyses were employed to investigate the relationship between the influencing factors. RESULTS: Increasing the number of training sessions enhanced the effectiveness of the AI models. The best-fit regression model for predicting the computational time of AI, which included logarithmic transformation of time, sample size, and training session variables, demonstrated an adjusted coefficient of determination of 0.99. CONCLUSION: The study results show that estimating the time required for AI development may be possible using logarithmic transformations of time, sample size, and training session variables, followed by applying coefficients estimated through several pilot studies with reduced sample sizes and reduced training sessions.

Guaiacol as an Organic Superoxide Dismutase Mimics for Anti-ageing a Ru-based Li-rich Layered Oxide Cathode.

High-capacity Li-rich layered oxides using oxygen redox as well as transition metal redox suffer from its structural instability due to lattice oxygen escaped from its structure during oxygen redox and the following electrolyte decomposition by the reactive oxygen species. Herein, we rescued a Li-rich layered oxide based on 4d transition metal by employing an organic superoxide dismutase mimics as a homogeneous electrolyte additive. Guaiacol scavenged superoxide radicals via dismutation or disproportionation to convert two superoxide molecules to peroxide and dioxygen after absorbing lithium superoxide on its partially negative oxygen of methoxy and hydroxyl groups. Additionally, guaiacol was decomposed to form a thin and stable cathode-electrolyte interphase (CEI) layer, endowing the cathode with the interfacial stability.

Breathable Artificial Interphase for Dendrite-Free and Chemo-Resistive Lithium Metal Anode.

A dendrite-free and chemically stabilized lithium metal anode is required for extending battery life and for the application of high energy density coupled with various cathode systems. However, uneven Li metal growth and the active surface in nature accelerate electrolyte dissipation and surface corrosion, resulting in poor cycle efficiency and various safety issues. Here, the authors suggest a thin artificial interphase using a multifunctional poly(styrene-b-butadiene-b-styrene) (SBS) copolymer to inhibit the electrochemical/chemical side reaction during cycling. Based on the physical features, hardness, adhesion, and flexibility, the optimized chemical structure of SBS facilitates durable mechanical strength and interphase integrity against repeated Li electrodeposition/dissolution. The effectiveness of the thin polymer film enables high cycle efficiency through the realization of a dendrite-free structure and a chemo-resistive surface of Li metal. The versatile anode demonstrates an improvement in the electrochemical properties, paired with diverse cathodes of high-capacity lithium cobalt oxide (3.5 mAh cm-2 ) and oxygen for advanced Li metal batteries with high energy density.

Biogenesis of chloroplast outer envelope membrane proteins.

Most organisms on Earth use glucose, a photosynthetic product, as energy source. The chloroplast, the home of photosynthesis, is the most representative and characteristic organelle in plants and is enclosed by the outer envelope and inner envelope membranes. The chloroplast biogenesis and unique functions are very closely associated with proteins in the two envelope membranes of the chloroplast. Especially, the chloroplast outer envelope membrane proteins have important roles in signal transduction, protein import, lipid biosynthesis and remodeling, exchange of ions and numerous metabolites, plastid division, movement, and host defense. Therefore, biogenesis of these membrane proteins of chloroplast outer envelope membrane is very important for biogenesis of the entire chloroplast proteome as well as plant development. Most proteins among the outer envelope membrane proteins are encoded by the nuclear genome and are post-translationally targeted to the chloroplast outer envelope membrane. In this process, cytoplasmic receptor and import machineries are required for efficient and correct targeting of these membrane proteins. In this review, we have summarized recent advances on the sorting, targeting, and insertion mechanisms of the outer envelope membrane proteins of chloroplasts and also provide future direction of the study on these topics.

Development of a Soy Protein Hydrolysate with an Antihypertensive Effect.

In this study, we combined enzymatic hydrolysis and lactic acid fermentation to generate an antihypertensive product. Soybean protein isolates were first hydrolyzed by Prozyme and subsequently fermented with Lactobacillus rhamnosus EBD1. After fermentation, the in vitro angiotensin-converting enzyme (ACE) inhibitory activity of the product (P-SPI) increased from 60.8 ± 2.0% to 88.24 ± 3.2%, while captopril (a positive control) had an inhibitory activity of 94.20 ± 5.4%. Mass spectrometry revealed the presence of three potent and abundant ACE inhibitory peptides, PPNNNPASPSFSSSS, GPKALPII, and IIRCTGC in P-SPI. Hydrolyzing P-SPI with gastrointestinal proteases did not significantly affect its ACE inhibitory ability. Also, oral administration of P-SPI (200 mg/kg body weight) to spontaneous hypertensive rats (SHRs) for 6 weeks significantly lowered systolic blood pressure (-19 ± 4 mm Hg, p < 0.05) and controlled body weight gain relative to control SHRs that were fed with physiological saline. Overall, P-SPI could be used as an antihypertensive functional food.

Shifting Target Reaction from Oxygen Reduction to Superoxide Disproportionation by Tuning Isomeric Configuration of Quinone Derivative as Redox Mediator for Lithium-Oxygen Batteries.

Quinones having a fully conjugated cyclic dione structure have been used as redox mediators in electrochemistry. 2,5-Ditert-butyl-1,4-benzoquinone (DBBQ or DB-p-BQ) as a para-quinone derivative is one of the representative discharge redox mediators for facilitating the oxygen reduction reaction (ORR) kinetics in lithium-oxygen batteries (LOBs). Herein, we presented that the redox activity of DB-p-BQ for electron mediation was possibly used for facilitating superoxide disproportionation reaction (SODR) by tuning the isomeric configuration of the carbonyl groups of the substituted quinone to change its reduction potentials. First, we expected a molecule having its reduction potential between oxygen/superoxide at 2.75 V versus Li/Li+ and superoxide/peroxide at 3.17 V to play a role of the SODR catalyst by transferring an electron from one superoxide (O2-) to another superoxide to generate dioxygen (O2) and peroxide (O22-). By changing the isomeric configuration from para (DB-p-BQ) to ortho (DB-o-BQ), the reduction potential of the first electron transfer (Q/Q-) of the ditert-butyl benzoquinone shifted positively to the potential range of the SODR catalyst. The electrocatalytic SODR-promoting functionality of DB-o-BQ kept the reactive superoxide concentration below a harmful level to suppress superoxide-triggered side reaction, improving the cycling durability of LOBs, which was not achieved by the para form. The second electron transfer process (Q-/ Q2-) of the DB-o-BQ, even if the same process of the para form was not used for facilitating ORR, played a role of mediating electrons between electrode and oxygen like the Q/Q- process of the para form. The ORR-promoting functionality of the ortho form increased the LOB discharge capacity and reduced the ORR overpotential.

Critical Void Dimension of Carbon Frameworks to Accommodate Insoluble Products of Lithium-Oxygen Batteries.

High-energy density lithium-oxygen batteries (LOBs) seriously suffer from poor rate capability and cyclability due to the slow oxygen-related electrochemistry and uncontrollable formation of lithium peroxide (Li2O2) as an insoluble discharge product. In this work, we accommodated the discharge product in macro-scale voids of a carbon-framed architecture with meso-dimensional channels on the carbon frame and open holes connecting the neighboring voids. More importantly, we found that a specific dimension of the voids guaranteed high capacity and cycling durability of LOBs. The best LOB performances were achieved by employing the carbon-framed architecture having voids of 0.8 µm size as the cathode of the LOB when compared with the cathodes having voids of 0.3 and 1.4 µm size. The optimized void size of 0.8 µm allowed only a monolithic integrity of lithium peroxide deposit within a void during discharging. The deposit was grown to be a yarn ball-looking sphere exactly fitting the shape and size of the void. The good electric contact allowed the discharge product to be completely decomposed during charging. On the other hand, the void space was not fully utilized due to the mass transfer pathway blockage at the sub-optimized 0.3 µm and the formation of multiple deposit integrities within a void at the sur-optimized 1.4 µm. Consequently, the critical void dimension at 0.8 µm was superior to other dimensions in terms of the void space utilization efficiency and the lithium peroxide decomposition efficiency, disallowing empty space and side reactions during discharging.

Amphi-Active Superoxide-Solvating Charge Redox Mediator for Highly Stable Lithium-Oxygen Batteries.

A multifunctional electrolyte additive for lithium oxygen batteries (LOBs) was designed to have (1) a redox-active moiety to mediate decomposition of lithium peroxide (Li2O2 as the final discharge product) during charging and (2) a solvent moiety to solvate and stabilize lithium superoxide (LiO2 as the intermediate discharge product) in electrolyte during discharging. 4-Acetamido-TEMPO (TEMPO = 2,2,6,6-tetramethylpiperidin-1-yl)oxyl) or AAT was employed as the additive working for both charge and discharge processes (amphi-active). The redox-active moiety was rooted in TEMPO, while the acetamido (AA) functional group inherited the high donor number (DN) of N,N-dimethylacetamide (DMAc). Integrating two functional moieties (TEMPO and AA) into a single molecule resulted in the bifunctionality of AAT (1) facilitating Li2O2 decomposition by the TEMPO moiety and (2) encouraging the solvent mechanism of Li2O2 formation by the high-DN AA moiety. Significantly improved LOB performances were achieved by the superoxide-solvating charge redox mediator, which were not obtained by a simple cocktail of TEMPO and DMAc.

A Three-Dimensional Nano-web Scaffold of Ferroelectric Beta-PVDF Fibers for Lithium Metal Plating and Stripping.

Lithium metal has been considered as an anode material to improve energy densities of lithium chemistry-based rechargeable batteries (that is to say, lithium metal batteries or LMBs). Higher capacities and cell voltages are ensured by replacing practically used anode materials such as graphite with lithium metal. However, lithium metal as the LMB anode material has been challenged by its dendritic growth, electrolyte decomposition on its fresh surface, and its serious volumetric change. To address the problems of lithium metal anodes, herein, we guided and facilitated lithium ion transport along a spontaneously polarized and highly dielectric material. A three-dimensional web of nanodiameter fibers of ferroelectric beta-phase polyvinylidene fluoride (beta-PVDF) was loaded on a copper foil by electrospinning (PVDF#Cu). The electric field applied between the nozzle and target copper foil forced the dipoles of PVDF to be oriented centro-asymmetrically and then the beta structure induced ferroelectric polarization. Three-fold benefits of the ferroelectric nano-web architecture guaranteed the plating/stripping reversibility especially at high rates: (1) three-dimensional scaffold to accommodate the volume change of lithium metal during plating and stripping, (2) electrolyte channels between fibers to allow lithium ions to move, and (3) ferroelectrically polarized or negatively charged surface of beta-PVDF fibers to encourage lithium ion hopping along the surface. Resultantly, the beta-PVDF web architecture drove dense and integrated growth of lithium metal within its structure. The kinetic benefit expected from the ferroelectric lithium ion transport of beta-PVDF as well as the porous architecture of PVDF#Cu was realized in a cell of LFP as a cathode and lithium-plated PVDF#Cu as an anode. Excellent plating/stripping reversibility along repeated cycles was successfully demonstrated in the cell even at a high current such as 2.3 mA cm-2, which was not obtained by the nonferroelectric polymer layer.

Anti-inflammatory mechanisms of resveratrol in activated HMC-1 cells: pivotal roles of NF-kappaB and MAPK.

Resveratrol is a phytoalexin polyphenolic compound found in various plants, including grapes, berries, and peanuts. Recently, studies have documented various health benefits of resveratrol including cardiovascular and cancer-chemopreventive properties. The aim of the present study was to demonstrate the effects of resveratrol on the expression of pro-inflammatory cytokines, as well as to elucidate its mechanism of action in the human mast cell line (HMC-1). Cells were stimulated with phorbol 12-myristate 13-acetate (PMA) plus A23187 in the presence or absence of resveratrol. To study the possible effects of resveratrol, ELISA, RT-PCR, real-time RT-PCR, Western blot analysis, fluorescence, and luciferase activity assays were used in this study. Resveratrol significantly inhibited the PMA plus A23187-induction of inflammatory cytokines such as tumour necrosis factor (TNF)-alpha, interleukin (IL)-6 and IL-8. Moreover, resveratrol attenuated cyclooxygenase (COX)-2 expression and intracellular Ca2+ levels. In activated HMC-1 cells, phosphorylation of extra-signal response kinase (ERK) 1/2 decreased after treatment with resveratrol. Resveratrol inhibited PMA plus A23187-induced nuclear factor (NF)-kappaB activation, IkappaB degradation, and luciferase activity. Resveratrol suppressed the expression of TNF-alpha, IL-6, IL-8 and COX-2 through a decrease in the intracellular levels of Ca2+ and ERK 1/2, as well as activation of NF-kappaB. These results indicated that resveratrol exerted a regulatory effect on inflammatory reactions mediated by mast cells.

Inhibition of LPS-induced iNOS, COX-2 and inflammatory mediator expression by paeonol through the MAPKs inactivation in RAW 264.7 cells.

We evaluated the in vivo anti-inflammatory and analgesic activities of orally administered paeonol in mice, and also investigated the anti-inflammatory activity of paeonol in a cell line. Paeonol significantly reduced the edema induced by arachidonic acid in rats. The analgesic effects were assayed using 2 different models, i.e., by acetic acid-induced writhing response and by formalin induced licking and biting time. Moreover, we examined the effects of paeonol on the release of inflammatory mediators such as NO, PGE(2) and IL-6. Our results demonstrated that paeonol inhibited LPS induced expression of NO, PGE(2) and IL-6. Paeonol prevented LPS induced iNOS, COX-2 and ERK activation. Therefore, paeonol appears to have potential as a treatment for inflammatory disease and analgesic.

Resistance to Cleavage of Core⁻Shell Rubber/Epoxy Composite Foam Adhesive under Impact Wedge⁻Peel Condition for Automobile Structural Adhesive.

Epoxy foam adhesives are widely used for weight reduction, watertight property, and mechanical reinforcement effects. However, epoxy foam adhesives have poor impact resistance at higher expansion ratios. Hence, we prepared an epoxy composite foam adhesive with core⁻shell rubber (CSR) particles to improve the impact resistance and applied it to automotive structural adhesives. The curing behavior and pore structure were characterized by differential scanning calorimetry (DSC) and X-ray computed tomography (CT), respectively, and impact wedge⁻peel tests were conducted to quantitatively evaluate the resistance to cleavage of the CSR/epoxy composite foam adhesives under impact. At 5 and 10 phr CSR contents, the pore size and expansion ratio increased sufficiently due to the decrease in curing rate. However, at 20 phr CSR content, the pore size decreased, which might be due to the steric hindrance effect of the CSR particles. Notably, at 0 and 0.1 phr foaming agent contents, the resistance to cleavage of the adhesives under the impact wedge⁻peel condition significantly improved with increasing CSR content. Thus, the CSR/epoxy composite foam adhesive containing 0.1 phr foaming agent and 20 phr CSR particles showed high impact resistance (EC = 34,000 mJ/cm²) and sufficient expansion ratio (~148%).

Biomimetic Superoxide Disproportionation Catalyst for Anti-Aging Lithium-Oxygen Batteries.

Reactive oxygen species or superoxide (O2-), which damages or ages biological cells, is generated during metabolic pathways using oxygen as an electron acceptor in biological systems. Superoxide dismutase (SOD) protects cells from superoxide-triggered apoptosis by converting superoxide to oxygen and peroxide. Lithium-oxygen battery (LOB) cells have the same aging problems caused by superoxide-triggered side reactions. We transplanted the function of SOD of biological systems into LOB cells. Malonic acid-decorated fullerene (MA-C60) was used as a superoxide disproportionation chemocatalyst mimicking the function of SOD. As expected, MA-C60 as the superoxide scavenger improved capacity retention along charge/discharge cycles successfully. A LOB cell that failed to provide a meaningful capacity just after several cycles at high current (0.5 mA cm-2) with 0.5 mAh cm-2 cutoff survived up to 50 cycles after MA-C60 was introduced to the electrolyte. Moreover, the SOD-mimetic catalyst increased capacity, e.g., more than a 6-fold increase at 0.2 mA cm-2. The experimentally observed toroidal morphology of the final discharge product of oxygen reduction (Li2O2) and density functional theory calculation confirmed that the solution mechanism of Li2O2 formation, more beneficial than the surface mechanism from the capacity-gain standpoint, was preferred in the presence of MA-C60.

Anti-nociceptive and anti-inflammatory effects of Angelicae dahuricae radix through inhibition of the expression of inducible nitric oxide synthase and NO production.

The extract of Angelicae dahuricae radix has traditionally been used as an anti-noceptive remedy in China. In this study, the methanol extract of Angelicae dahuricae radix (MEAD) was evaluated to determine if it has anti-noceptive and anti-inflammatory action. The anti-nociceptive activities of MEAD were evaluated by determining the writhing response and sleeping time, as well as by a formalin test. In addition, the anti-inflammatory activities of MEAD were evaluated by a vascular permeability test as well as by measuring the carrageenan-induced paw edema and conducting a myeloperoxidase (MPO) assay. MEAD (600 and 1200 mg/kg) exhibited anti-inflammatory effects on acetic acid-induced vascular permeability, carrageenan-induced paw edema, and MPO activity. Moreover, the results of the formalin test, the acetic acid-induced writhing response and the pentobarbital-induced sleeping time indicated that MEAD had anti-nociceptive effects that occurred in a concentration-dependent manner. To determine the mechanism by which MEAD exerted its effects on the expression of inducible nitric oxide synthase (iNOS) and the production of nitric oxide (NO) by treated murine macrophage RAW 264.7 cells was evaluated. Similar to the in vivo activities, both the iNOS expression and NO production were significantly suppressed by MEAD in a dose-dependent manner. Furthermore, MEAD inhibited the activating phosphorylation of ERK1/2. These results provide a scientific basis that explains the mechanism by which Angelicae dahuricae radix relieves inflammatory pain.

Discrimination of Korean ginseng (Panax ginseng Meyer) cultivar Chunpoong and American ginseng (Panax quinquefolius) using the auxin repressed protein gene.

BACKGROUND: Korean ginseng (Panax ginseng) is one of the most important medicinal plants in the Orient. Among nine cultivars of P. ginseng, Chunpoong commands a much greater market value and has been planted widely in Korea. Chunpoong has superior quality "Chunsam" (1st grade ginseng) when made into red ginseng. METHODS: A rapid and reliable method for discriminating the Chunpoong cultivar was developed by exploiting a single nucleotide polymorphism (SNP) in the auxin repressed protein gene of nine Korean ginseng cultivars using specific primers. RESULTS: An SNP was detected between Chunpoong and other cultivars, and modified allele-specific primers were designed from this SNP site to specifically identify the Chunpoong cultivar and P. quinquefolius via multiplex polymerase chain reaction (PCR). CONCLUSION: These results suggest that great impact to prevent authentication of precise Chunpoong and other cultivars using the auxin repressed protein gene. We therefore present an effective method for the authentication of the Chunpoong cultivar of P. ginseng and P. quinquefolius.

Double-injection perivascular ultrasound-guided axillary brachial plexus block according to needle positioning: 12 versus 6 o'clock position of the axillary artery.

BACKGROUND: We conducted prospective, randomized, observer-blinded trial to compare two double-injection perivascular (PV) ultrasound-guided techniques of axillary brachial plexus block (BPB). METHODS: American Society of Anesthesiologists physical status I-II, 50 patients undergoing surgery of the forearm, wrist or hand were randomly allocated to two groups. For PV12 group, injection was carried out at the 12 o'clock position using 24 ml of 2% lidocaine. Patients of PV6 group got their injection of 24 ml of 2% lidocaine at direction of 6 o'clock of axillary artery. For all 2 groups, the musculocutaneous nerve was identified and 5 ml of 2% lidocaine was deposited around the nerve. The performance time and the onset time were recorded. The induction time (sum of performance and onset time), the success rate of the block, the need rate of rescue block, and incidence of adverse events was compared. RESULTS: The success rate was same (84%) in two groups. The performance time, onset time, and induction time showed no differences between two groups. There were no differences in vessel puncture, paresthesia, and numbness. CONCLUSIONS: Double-injection perivascular ultrasound-guided axillary BPB can be performed at 12 o'clock or 6 o'clock position of axillary artery, and performer may choose needle targeting position by considering surgery site. Thus perivascular double-injection technique may be an alternative method for axillary BPB and useful in case of difficult block.

Direct integration of polycrystalline graphene into light emitting diodes by plasma-assisted metal-catalyst-free synthesis.

The integration of graphene into devices is a challenging task because the preparation of a graphene-based device usually includes graphene growth on a metal surface at elevated temperatures (∼1000 °C) and a complicated postgrowth transfer process of graphene from the metal catalyst. Here we report a direct integration approach for incorporating polycrystalline graphene into light emitting diodes (LEDs) at low temperature by plasma-assisted metal-catalyst-free synthesis. Thermal degradation of the active layer in LEDs is negligible at our growth temperature, and LEDs could be fabricated without a transfer process. Moreover, in situ ohmic contact formation is observed between DG and p-GaN resulting from carbon diffusion into the p-GaN surface during the growth process. As a result, the contact resistance is reduced and the electrical properties of directly integrated LEDs outperform those of LEDs with transferred graphene electrodes. This relatively simple method of graphene integration will be easily adoptable in the industrialization of graphene-based devices.

Molecular characterization of two glutathione peroxidase genes of Panax ginseng and their expression analysis against environmental stresses.

Glutathione peroxidases (GPXs) are a group of enzymes that protect cells against oxidative damage generated by reactive oxygen species (ROS). GPX catalyzes the reduction of hydrogen peroxide (H2O2) or organic hydroperoxides to water or alcohols by reduced glutathione. The presence of GPXs in plants has been reported by several groups, but the roles of individual members of this family in a single plant species have not been studied. Two GPX cDNAs were isolated and characterized from the embryogenic callus of Panax ginseng. The two cDNAs had an open reading frame (ORF) of 723 and 681bp with a deduced amino acid sequence of 240 and 226 residues, respectively. The calculated molecular mass of the matured proteins are approximately 26.4kDa or 25.7kDa with a predicated isoelectric point of 9.16 or 6.11, respectively. The two PgGPXs were elevated strongly by salt stress and chilling stress in a ginseng seedling. In addition, the two PgGPXs showed different responses against biotic stress. The positive responses of PgGPX to the environmental stimuli suggested that ginseng GPX may help to protect against environmental stresses.

Direction of catheter insertion and the incidence of paresthesia during continuous epidural anesthesia in the elderly patients.

BACKGROUND: Continuous epidural anesthesia is useful for endoscopic urologic surgery, as mostly performed in the elderly patients. In such a case, it is necessary to obtain successful sacral anesthesia, and the insertion of epidural catheter in the caudad direction may be needed. However, continuous epidural catherization has been related to paresthesias. This study aimed to evaluate the effects of the direction of the catheter insertion on the incidence of paresthesias in the elderly patients. METHODS: Two hundred elderly patients scheduled for endoscopic urologic surgery were enrolled. The epidural catheter was inserted at L2-3, L3-4, and L4-5 using the Tuohy needle. In Group I (n = 100), the Tuohy needle with the bevel directed the cephalad during the catheter insertion. In Group II (n = 100), it directed the caudad. During the catheter insertion, an anesthesiologist evaluated the presence of paresthesias and the ease or difficulty during the catheter insertion. RESULTS: In Group I (n = 97), 15.5% of the patients had paresthesias versus 18.4% in Group II (n = 98), and there was no significant difference between the two groups. In paresthesia depending on the insertion site and the ease or difficulty during the catheter insertion, there were no significant differences between the two groups. CONCLUSIONS: Our results concluded that the direction of epidural catheter insertion did not significantly influence the incidence of paresthesias in the elderly patients.

Less strained and more efficient GaN light-emitting diodes with embedded silica hollow nanospheres.

Light-emitting diodes (LEDs) become an attractive alternative to conventional light sources due to high efficiency and long lifetime. However, different material properties between GaN and sapphire cause several problems such as high defect density in GaN, serious wafer bowing, particularly in large-area wafers, and poor light extraction of GaN-based LEDs. Here, we suggest a new growth strategy for high efficiency LEDs by incorporating silica hollow nanospheres (S-HNS). In this strategy, S-HNSs were introduced as a monolayer on a sapphire substrate and the subsequent growth of GaN by metalorganic chemical vapor deposition results in improved crystal quality due to nano-scale lateral epitaxial overgrowth. Moreover, well-defined voids embedded at the GaN/sapphire interface help scatter lights effectively for improved light extraction, and reduce wafer bowing due to partial alleviation of compressive stress in GaN. The incorporation of S-HNS into LEDs is thus quite advantageous in achieving high efficiency LEDs for solid-state lighting.