Development of NaY9Si6O26:Yb3+ phosphors with high thermal stability for NIR anti-counterfeiting: study of its crystal structure and luminescent properties.

Near-infrared (NIR) radiation has generated considerable industrial and research interest. However, NIR phosphors for this are limited by low quantum efficiency and broad spectra. Rare-earth-containing compounds doped with activators as host systems for NIR phosphors may resolve these limitations. Yb3+-doped NaY9Si6O26 phosphors were synthesized using a conventional solid-state reaction method. The main phase of the synthesized phosphor samples exhibited a hexagonal structure NaY9Si6O26 phase, and had an angular-shape with an average grain size of 1-3 µm. The NaY9Si6O26:Yb3+ phosphors showed a near-infrared emission from 950 to 1100 nm, which was attributed to the 2F5/2 → 2F7/2 transition of Yb3+ ions under 270 and 920 nm excitation. The excitation spectra, recorded by monitoring the emission at 985 nm, showed two bands in the ultraviolet and infrared regions, which correspond to the charge transfer transition and the 2F7/2 → 2F5/2 transition of Yb3+ ions. At 300 °C, the emission intensity of the NaY9Si6O26:Yb3+ phosphor remained constant at 82%. Furthermore, the thermal degradation was negligible after cooling, suggesting the possibility of application in advanced anti-counterfeiting applications.

Phase-selective synthesis of lead-free CsMnBr3 and Cs3MnBr5 nanocrystals dependent on solvent concentration.

We demonstrate the crystal phase-selective synthesis for lead-free cesium manganese bromine perovskite nanocrystals synthesized by the modified hot-injection method due to changing the concentration of solvent (trioctylphosphine; TOP). The compositions synthesized were determined by the amount of TOP solvent, and the structure phase of the nanocrystals was selected from hexagonal CsMnBr3 to tetragonal Cs3MnBr5 as the amount of TOP solvent increased. The emission peaks of CsMnBr3 and Cs3MnBr5 nanocrystals were observed at 650 nm (red) and 520 nm (green), respectively. After a durability test at 85°C and 85% humidity for 24 h, the lead-free perovskite CsMnBr3 nanocrystal powder maintained its initial emission intensity, and the metal halide Cs3MnBr5 nanocrystal powder exhibited an increase in red emission due to the post-synthesis of CsMnBr3 nanocrystals.

Eu3+-doped Bi2MoO6 phosphors for highly sensitive and visible H2S gas indicator material: optical and color properties, and gas sensing performance.

Bi2MoO6:Eu3+ phosphors were synthesized by a solid state reaction, and H2S gas sensing performance was investigated. The Bi2MoO6:Eu3+ phosphors showed an excellent red emission due to f-f transition of Eu3+. Owing to the exposure to H2S gas, the emission intensity of the phosphors dramatically decreased to 40% of the initial value. The body color of the phosphor changed from yellow-white to dark brown. The response of the Bi2MoO6:Eu3+ phosphors for H2S gas was started from 10 ppm, and the emission intensity exponentially decreased with increasing the concentration until 500 ppm.

Development of a cyan blue-emitting Ba3La2(BO3)4:Ce3+,Tb3+ phosphor for use in dental glazing materials: color tunable emission and energy transfer.

The Ce3+/Tb3+ doped Ba3La2(BO3)4 phosphors were synthesized by a conventional solid state reaction method. The synthesized phosphor samples are a single phase of Ba3La2(BO3)4 and showed angular-shaped fine grains with average particle size from 5 µm to 10 µm. The Ba3La2(BO3)4:Ce3+ phosphors showed an asymmetric broad blue emission under excitation at 365 nm and the Ba3La2(BO3)4:Tb3+ phosphors exhibited typical green emission assigned to the 4f-4f transition of Tb3+ under excitation at 254 nm. Under near-UV (365 nm) excitation, Ba3La2(BO3)4:Ce3+,Tb3+ phosphors showed both a blue emission band and green emission peaks due to Ce3+ and Tb3+, respectively. By optimizing the composition, cyan-blue emission with high color purity (CIE chromaticity coordinate values x = 0.2557 and y = 0.3839) was obtained for the Ba3La2(BO3)4:0.05Ce3+,0.03Tb3+ phosphor, and the internal quantum efficiency of the phosphor at the excitation wavelength of 365 nm is estimated to be 50%. The dental glazing paste prepared by mixing organic binder, Ba3La2(BO3)4:Ce3+,Tb3+ phosphors, and low T g glass was successfully vitrified when it was heated at 600 and 700 °C, and showed high chemical stability of the luminescence properties in acidic aqueous solution (pH = 4).

Quality of life of patients with nasal bone fracture after closed reduction.

BACKGROUND: Closed reduction is the standard treatment for nasal bone fractures, which are the most common type of facial bone fractures. We investigated the effect of closed reduction on quality of life. METHODS: The 15-dimensional health-related quality of life survey was administered to 120 patients who underwent closed reduction under general anesthesia for nasal bone fractures from February 2018 to December 2019, on both the day after surgery and 3 months after surgery. Three months postoperatively, the presence or absence of five nasal symptoms (nose obstruction, snoring, pain, nasal secretions, and aesthetic dissatisfaction) was also evaluated. RESULTS: The quality of life items that showed significant changes between immediately after surgery and 3 months postoperatively were breathing, sleeping, speech, excretion, and discomfort. Low scores were found at 3 months for breathing, sleeping, and distress. There were 31 patients (25.83%) with nose obstruction, 25 (20.83%) with snoring, 12 (10.00%), with pain, 11 (9.17%) with nasal secretions, and 29 (24.17%) with aesthetic dissatisfaction. CONCLUSION: Closed reduction affected patients' quality of life, although most aspects improved significantly after 3 months. However, it was not possible to rule out deterioration of quality of life due to complications and dissatisfaction after surgery.

A retrospective study of changes in skin cancer characteristics over 11 years.

BACKGROUND: The incidence of skin cancer, which is primarily caused by exposure to ultraviolet radiation, has steadily increased in recent years. The authors of the present study sought to investigate changes in the epidemiology of skin cancer by conducting a retrospective review of patients diagnosed with skin cancer who received related care at a single medical institution.
. METHODS: The present study included patients who were diagnosed with skin cancer and received treatment at Gyeongsang National University Hospital from 2008 to 2018. The site and type of skin cancer, the number of patients with skin cancer each year, the sex and sex ratio of the patients, and changes in patients' age at first diagnosis were examined through retrospective chart reviews.
. RESULTS: The number of patients with skin cancer significantly increased, but statistically significant changes were not found in patients' sex, skin cancer sites, or the types of skin cancer. However, patients' age at the first diagnosis of skin cancer showed a statistically significant decrease starting in 2015.
. CONCLUSION: In this study, the number of patients with skin cancer increased over time. However, patients' age at first diagnosis has decreased since 2015. Therefore, younger patients should take care to prevent skin cancer, and further research on the causes of skin cancer in younger patients is needed.

The clinical usefulness of closed reduction of nasal bone using only a periosteal elevator with a rubber band.

BACKGROUND: Closed reduction of nasal fracture with various instrument is performed to treat nasal fracture. Depending on the type of nasal fracture and the situation in which it is being operated, the surgeon will determine the surgical tool. The objective of this study was to investigate whether a periosteal elevator (PE) was a proper device to perform closed reduction for patients with simple nasal fractures. METHODS: From March 2018 to December 2018, 50 cases of simple nasal bone fracture underwent closed reduction performed by a single surgeon. These patients were divided into two groups randomly: nasal bone reduction was performed using only PE (freer) and nasal bone reduction was performed using Walsham, Asch forcep, and Boies elevator (non-freer, non-PE). RESULTS: The paranasal sinus computed tomography was performed on patients before and after operation to carry out an accurate measurement of reduction distance at the same level. According to the results, the interaction between instruments and fracture types had a significant influence on reduction distance (p = 0.021). To be specific, reduction distance was significantly (p= 0.004) increased by 2.157 mm when PE was used to treat patients with partial displacement compared to that when non-PEs were used. CONCLUSION: Closed reduction using PE and other elevator is generally an effective treatment for nasal fracture. In partial-displacement type of simple nasal fracture, closed reduction using PE can have considerable success in comparison with using classic instruments.

Immediate regraft of the remnant skin on the donor site in split-thickness skin grafting.

BACKGROUND: Skin defects of head and neck need reconstruction using various local flaps. In some cases, surgeons should consider skin graft for large skin defect. It is important to heal skin graft and donor sites. The authors investigated wound healing mechanisms at the donor sites with split-thick-ness skin graft (STSG). In this study, the authors compared two types of immediate regraft including sheets and islands for the donor site after facial skin graft using remnant skin. METHODS: The author reviewed 10 patients who underwent STSG, from March 2015 to May 2017, for skin defects in the craniofacial area. The donor site was immediately covered with the two types using remnant skin after harvesting skin onto the recipient site. Depending on the size of the remnant skin, we conducted regraft with the single sheet (n= 5) and island types (n= 5). RESULTS: On postoperative day 1 and 3 months, the scar formation was evaluated using the Patient and Observer Scar Assessment Scale (POSAS) and Vancouver Scar Scale (VSS). Total POSAS and VSS scores for the island type were lower than in single sheet group after 3 months postoperatively. There was significant difference in specific categories of POSAS and VSS. CONCLUSION: This study showed a reduction in scar formation following immediate regrafting of the remnant skin at the donor site after STSG surgery. Particularly, the island type is useful for clinical application to facilitate healing of donor sites with STSG.

Development of high luminous efficacy red-emitting phosphor-in-glass for high-power LED lighting systems using our original low Tg and Ts glass.

Red-emitting phosphor-in-glass (PiG) materials with a high luminescence efficiency were developed by co-firing commercial red-emitting (Sr,Ca)AlSiN3:Eu2+ (SCASN) phosphor and our original glass frits with a composition of Li2O-Na2O-ZnO-Al2O3-B2O3-P2O5, which has a low Tg (271°C) and Ts (380°C) temperatures. By optimizing the sintering temperature and the content of the phosphor, the highest luminous efficacy was obtained for the 3 wt.% SCASN-based PiG sintered at 400°C, which showed a luminous efficacy of 25 lm/W rad by combining the PiG materials with a blue light-emitting diode (LED) chip-on-board (COB, incident power = 100 mA). The internal quantum efficiency of this sample under excitation at 450 nm was 53%. The PiG-based LED maintained a high luminous efficacy when the incident power of the blue COB increased up to 5.5 W (47 lm).

Reconstruction of nasal ala and tip following skin cancer resection.

BACKGROUND: Defects of the nasal ala and tip have a complex three-dimensional structure that makes them challenging to reconstruct. Many reconstructive options have been described for nasal ala and tip defects, ranging from primary closure to local flaps and skin grafts. However, it is difficult to determine which method will yield the best cosmetic results in each individual case. Thus, the purpose of this study was to determine which surgical procedures for reconstructing defects of the nasal ala and tip have better cosmetic results. METHODS: From 2008 to 2018, 111 patients underwent surgery to reconstruct skin defects after resection of skin cancer in the nasal ala or tip. Their charts were reviewed to obtain data on age, sex, surgical location, size of the defect, surgical method, and cosmetic results using a visual analog scale (VAS). RESULTS: For nasal ala reconstruction, the most commonly used surgical technique was the nasolabial flap (n= 42). This method also had the highest VAS score (7/10). The most commonly selected surgical method for nasal tip reconstruction was the bilobed flap (n= 13), and bilobed flaps and primary closure had the highest VAS score (7/10). CONCLUSION: Nasolabial flaps showed excellent cosmetic results for the reconstruction of nasal ala defects, while primary closure and bilobed flaps yielded excellent cosmetic results for the reconstruction of nasal tip defects.

Cutaneous Leiomyosarcoma of the Face.

Cutaneous leiomyosarcoma is an uncommon superficial soft tissue sarcoma and mainly found in the middle aged to elderly males. It can occur in any part of the body, mostly affecting the extremities and rarely affecting the face. It grows relatively slowly, can be diagnosed by biopsy and is treated by surgical excision. It needs to be distinguished from other spindle cell neoplasms, and immunohistochemical markers are usually required to attain an accurate diagnosis. We report a case of cutaneous leiomyosarcoma appeared on the left cheek within 6 month of a 73-year-old female patient suspected with malignant melanoma before surgery.

Cutaneous Basal Cell Carcinoma Arising in Odontogenic Cutaneous Fistula.

An odontogenic cutaneous fistula is a pathological communication between the outer skin surface of the face and the oral cavity. Facial cutaneous fistula is a complication of odontogenic infection that is often misdiagnosed with skin infection. We report a rare case, which was diagnosed as basal cell carcinoma based on the biopsy of skin lesions in the patient who had been diagnosed with odontogenic cutaneous fistula. A 64-year-old male patient presented with a cutaneous odontogenic fistula. The patient had undergone surgical extraction of fistula tract and loose tooth before dermatology or plastic surgery consultation. With the biopsy and computed tomography, it was confirmed that fistula and basal cell carcinoma. However, the connection between the fistula and skin cancer was not clear. Positron emission tomography-computed tomography scan was performed and was not detected as other local or distant metastasis. After that, wide excision of the skin lesion was performed. Although skin cancer is not commonly observed, it is necessary to rule out this disease entity by performing biopsy of skin lesions.

A Comparison of the Local Flap and Skin Graft by Location of Face in Reconstruction after Resection of Facial Skin Cancer.

BACKGROUND: Surgery for reconstruction of defects after surgery should be performed selectively and the many points must be considered. The authors conducted this study to compare the local flap and skin graft by facial location in the reconstruction after resection of facial skin cancer. METHODS: The authors performed the study in patients that had received treatment in Department of Plastic Surgery, Gyeongsang National University. The cases were analyzed according to the reconstruction methods for the defects after surgery, sex, age, tumor site, and tumor size. Additionally, the authors compared differences of aesthetic satisfaction (out of 5 points) of patients in the local flap and skin graft by facial location after resection of facial skin cancer by dividing the face into eight areas. RESULTS: A total of 153 cases were confirmed. The most common facial skin cancer was basal cell carcinoma (56.8%, 87 cases), followed by squamous cell carcinoma (37.2%, 57 cases) and bowen's disease (5.8%, 9 cases). The most common reconstruction method was local flap 119 cases (77.7%), followed by skin graft 34 cases (22.3%). 86 patients answered the questionnaire and mean satisfaction of the local flap and skin graft were 4.3 and 3.5 (p=0.04), respectively, indicating that satisfaction of local flap was significantly high. CONCLUSION: When comparing satisfaction of patients according to results, local flap shows excellent effects in functional and cosmetic aspects would be able to provide excellent results rather than using a skin graft with poor touch and tone compared to the surrounding normal skin.

Reduction of Zygomatic Arch Isolated Fracture Using Ultra Sound and Needle Marking.

BACKGROUND: Zygomatic arch is a bony arch constituting the lateral midface, which consists of 25% of all midface fractures. There are a number of ways to evaluate the extent of zygomatic arch fracture. Some authors have reported successful treatment outcomes using ultrasound (U/S). To add to the previous methods, we have considered ways to accurately display the location of the fracture line while using U/S with 23 gauge needle marking. We introduce our method, which provided satisfactory results for reduction using a portable U/S, and it can evaluate the fracture line simultaneously when reduction of an isolated zygomatic arch fracture is necessary, and needle marking, which can easily point out the fracture line on U/S. METHODS: We studied 21 patients with an isolated zygomatic arch fracture who underwent closed reduction using U/S and needle marking between 2013 and 2015. RESULTS: We achieved satisfactory results in all our cases with respect to reduction by using the Dingman elevator after performing a temporal approach incision, while confirming relative positioning between needle marking and zygomatic fracture at the same time, after insertion of a 23 gauge needle in the skin above the zygomatic arch fracture line parallel to it. CONCLUSION: We treated 21 patients with an isolated zygomatic arch fracture using U/S and the needle marking method, which provided satisfactory results because the extent of reduction of the fracture could be evaluated in real-time during the operation and exposure to radiation was reduced.