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The in vitro propagation and ex situ conservation strategy provides new means for the conservation and mass propagation of economically and medicinally important plants. The present work aimed to observe the main characteristics of the in vitro propagation of Garcinia livingstonei from matured seed segments. Successful multiple shoots were induced on a woody plant (WP) medium supplemented with cytokinins. An average of 13.0 shoots per explant were grown from matured seed segments on a WP medium containing 15.0 µM BAP after 12 weeks of culture. The shoot elongation and multiplication were achieved using a repeated and periodic subculturing of shoot clumps in the same medium. The optimum in vitro rooting of shoots was obtained on the half-strength WP medium supplemented with IBA (5.0 µM). The regenerated plantlets were successfully transplanted to pots containing soil, sand, and farmyard manure (1:1:1) and were maintained in a greenhouse with a survival frequency was 80%.

The urethral catheter is used in various clinical situations such as diagnosing urologic disease, urine drainage in patients after surgery, and for patients who cannot urinate voluntarily. However, catheters can cause numerous adverse effects, such as catheter-associated infection, obstruction, bladder stones, urethral injury, and catheter-related bladder discomfort (CRBD). CRBD symptoms vary among patients from burning sensation and pain in the suprapubic and penile areas to urinary urgency. CRBD significantly reduces patient quality of life and can lead to several complications. CRBD is caused by catheter-induced bladder irritation due to muscarinic receptor-mediated involuntary contractions of bladder smooth muscle and also can be caused by mechanical stimulus of the urethral catheter. Various pharmacologic studies for managing CRBD, including antimuscarinic and antiepileptic agents and botulinum toxin injections have been reported. If urologists can reduce patients’ CRBD, their quality of life and recovery can improve.

In Camellia japonica callus culture, the effects of light quality on the accumulation of phenolic compounds were examined. To this end, the calli were cultured under three monochrome [white (W), red (R), and blue (B)] and two mixed [red/blue (RB) and red/green/blue (RGB)] light sources. After 4 weeks of culture, fresh and dry callus weights were determined, and phenolic content was analyzed using high-performance liquid chromatography. We also examined the effects of RGB light on calli derived from four origins (leaf: CL; root: CR; petal: CP; and ovary: CO). Total phenolic and flavonoid content and DPPH radical scavenging activity were highest in calli exposed to RB and RGB. Catechin was detected only in calli exposed to mixed light (RB and RGB). Interestingly, red pigmentation development in CL and CR calli after 2 weeks of culture and organogenic calli in CR and CP samples was observed. Furthermore, expression of the phenylalanine ammonia lyase and chalcone synthase genes was found to be higher in the CR line than in other lines, and total phenolic and flavonoid content was also higher in the CR and CP lines. The findings of the present study revealed that the accumulation of phenolics and flavonoids in callus tissue varies depending on light quality, which stimulates cell division, and may thus affect the proliferation and organogenesis of C. japonica callus. We also established that the effects of light on red pigment expression and the accumulation of bioactive compounds are dependent on the tissue origin of callus material.

In this study, an external light extraction layer with a micro-nano hybrid structure was applied to improve the external light extraction efficiency of organic light-emitting diodes (OLEDs). A reactive ion-etching (RIE) process, using O2 and CHF3 plasma, was performed on the surface of the micro-scale pattern to form micro-nano hybrid structures. According to the results of this study, the nanostructures formed by the treatment of O2 and CHF3 were different, and the efficiency according to the structures was analyzed experimentally and theoretically. As a result, the OLED, to which the micro-nano hybrid structure, manufactured through a simple process, is applied, improved the external light extraction efficiency by up to 38%, and an extended viewing angle profile was obtained. Additionally, an effective method for enhancing the out-coupling efficiency of OLEDs was presented by optimizing the micro-nano hybrid structure according to process conditions.

In this study, we fabricated a random nanostructure (RNS) external light extraction composite layer containing high-refractive-index nanoparticles through a simple and inexpensive solution process and a low-temperature mask-free process. We focused on varying the shape and density of the RNSs and adjusted the concentration of the high-refractive-index nanoparticles to control the optical properties. The RNSs fabricated using a low-temperature mask-free process can use the distance between the nanostructures and various forms to control the diffraction and scattering effects in the visible light wavelength range. Consequently, our film exhibited a direct transmittance of ~85% at a wavelength of 550 nm. Furthermore, when the RNSs’ composite film, manufactured using the low-temperature mask-free process, was applied to organic light-emitting diodes (OLEDs), it exhibited an external quantum efficiency improvement of 32.2% compared with the OLEDs without the RNSs. Therefore, the randomly distributed high-refractive-index nanoparticles on the polymer film can reduce the waveguide mode and total reflection at the substrate/air interface. These films can be used as a scattering layer to reduce the loss of the OLED substrate mode.

Lilium dauricum is a rare and endangered species belonging to the family Liliaceae. The species contains several bioactive compounds used as functional foods and medicinal agents in Northeast Asia. This study aimed (1) to establish an in vitro bulblet culture using an air-lift bioreactor and callus culture for the conservation of L. dauricum and obtaining its bioactive compounds; (2) investigate the plant phenolic compounds from both cultures system. The highest bulblet production with 12.5-fold increase in growth rate was obtained using MS medium supplemented with 0.5 g L-1 BA and 3% sucrose. Addition of 7% sucrose facilitated bulblet enlargement, with approximate 2.5- and 7-fold increases in diameter and fresh weight, respectively. The highest rate of callus (100%) was obtained using a combination of 1.0 mg L-1 picloram and 0.5 mg L-1 Kinetin. The callus proliferation occurred on MS medium supplemented with 1.0 mg L-1 picloram, 0.25 mg L-1 kinetin, and 0.25 g L-1 casein hydrolysate. There was a significant difference in the total phenolic compound content of callus, which was 1.5-fold higher than that in the bulblets. These findings indicate a suitable system for optimizing both bulblet and callus culture of L. dauricum, therefore, providing useful bio-materials for industrial purposes and contributing to the conservation of this species.