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1.
Small Methods ; 6(11): e2200880, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36250995

RESUMO

Ruddlesden-Popper oxides (A2 BO4 ) have attracted significant attention regarding their potential application in novel electronic and energy devices. However, practical uses of A2 BO4 thin films have been limited by extended defects such as out-of-phase boundaries (OPBs). OPBs disrupt the layered structure of A2 BO4 , which restricts functionality. OPBs are ubiquitous in A2 BO4 thin films but inhomogeneous interfaces make them difficult to suppress. Here, OPBs in A2 BO4 thin films are suppressed using a novel method to control the substrate surface termination. To demonstrate the technique, epitaxial thin films of cuprate superconductor La2- x Srx CuO4 (x = 0.15) are grown on surface-reconstructed LaSrAlO4 substrates, which are terminated with self-limited perovskite double layers. To date, La2- x Srx CuO4 thin films are grown on LaSrAlO4 substrates with mixed-termination and exhibit multiple interfacial structures resulting in many OPBs. In contrast, La2- x Srx CuO4 thin films grown on surface-reconstructed LaSrAlO4 substrates energetically favor only one interfacial structure, thus inhibiting OPB formation. OPB-suppressed La2- x Srx CuO4 thin films exhibit significantly enhanced superconducting properties compared with OPB-containing La2- x Srx CuO4 thin films. Defect engineering in A2 BO4 thin films will allow for the elimination of various types of defects in other complex oxides and facilitate next-generation quantum device applications.

2.
Sci Rep ; 10(1): 8541, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32444643

RESUMO

For 60-GHz band communications, both the mutual coupling and transmission distance restrict the performance of a multiple-input multiple-output (MIMO) antenna array. Several studies presented different types of meta-materials and electromagnetic bandgap (EBG) structures to improve the performance of a MIMO antenna array at the 60-GHz band. In this paper, we presented the four-element MIMO patch antenna with different types of EBG structures for the millimeter wave (mmW)communications at the 60-GHz unlicensed industrial, scientific, and medical band. The single element of the MIMO antenna array covered the mmW band from 57 GHz to 63 GHz having the dimensions of 1.3 mm × 1.8 mm × 0.1 mm. We developed a set of square-shaped, cross-shaped, and complex-slotted EBG ground planes between the antenna elements for the performance improvement. All the three EBG ground planes provided significant coupling reduction between the mmW MIMO antenna elements. The proposed EBG structures exhibited wide bandgap characteristics and improved scattering parameters in the desired frequency band. In contrast with the cross- and complex-slotted, the square-shaped EBG structure substantially improved the overall gain of MIMO antenna array. In addition, the square-shaped EBG reformed the maximum beam and enhanced the far-field gain pattern in the desired direction. Experimental results conducted with the fabricated prototypes showed a good agreement with the simulation results and adequately covered the 60-GHz band. The low-profile and salient features of the proposed MIMO antenna array shows the potential for on-chip applications at 60 GHz.

3.
Maxillofac Plast Reconstr Surg ; 38(1): 6, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26870717

RESUMO

BACKGROUND: Intravenous bisphosphonates have been used in metastatic breast cancer patients to reduce pathologic bone fracture and bone pain. However, necrosis of the jaw has been reported in those who received intravenous bisphosphonates. Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is caused by dental extraction, dental implant surgery, and denture wearing; however, it occurs spontaneously. The purpose of this study was to report BRONJ in metastatic breast cancer patients. METHODS: Consecutive 25 female patients were referred from the Department of Oncology from 2008 to 2014 for jaw bone discomfort. Staging of breast cancer, history of bisphosphonate infusion, etiology of BRONJ, and treatment results were reviewed. Average age of the patients was 55.4 years old (38-74). Twelve maxillae and 16 mandibles were involved. Conservative treatments such as irrigation, antibiotic medication, analgesics, and oral gargle were applied for all patients for the initial treatment. Patients who had sequestrum underwent debridement and primary closure. RESULTS: The etiologies of BRONJ were dental extraction (19 cases), dental implant (2 cases), and endodontic treatment (1 case). However, three patients did not have any risk factors to cause BRONJ. Three patients died of progression of metastasis during follow-up periods. Surgical debridement was performed in 21 patients with success in 18 patients. Three patients showed recurred bone exposure and infection after operation. CONCLUSIONS: Prevention of the BRONJ is critical in metastatic breast cancer patients. Conservative treatment to reduce pain, discomfort, and infection is recommended for the initial therapy. However, if there is a sequestrum, surgical debridement and primary closure is the key to treat the BRONJ.

4.
Maxillofac Plast Reconstr Surg ; 37(1): 45, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26693164

RESUMO

BACKGROUND: Radial forearm free flap is the most reliable flap for intraoral soft tissue reconstruction after cancer ablation surgery. However, unesthetic scar of the donor site and the need for a second donor site for skin graft are major disadvantages of the forearm flap. The purpose of this study was to report the clinical results of double-layered collagen graft to the donor site of the forearm free flap without skin graft. METHODS: Twenty-two consecutive patients who underwent oral cancer ablation and forearm reconstruction between April 2010 and November 2013 were included in this study. Male to female ratio was 12:10, and average age was 61.0 years old (27-84). Double-layered collagen was grafted to the donor site of the forearm free flap and healed for secondary intention. Upper silicone had been trimmed at the periphery during secondary intention, and dry dressing was used. Postoperative scar healing and esthetic results and function were evaluated. RESULTS: An average follow-up period was 34.9 months. The scar area was decreased to 63.9 % in average. The complete healing was obtained between 1.5 and 3 months according to the defect size. There was no functional defect or impairment 3 months after operation. All patients were satisfied with the esthetic results. Three patients died of recurred cancer. CONCLUSIONS: Double-layered collagen graft was successfully performed in this study. Without the thigh skin graft, patients had experienced less painful postoperative healing periods and discomfort.

5.
Biol Pharm Bull ; 28(7): 1177-82, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15997093

RESUMO

Gamisanghyulyunbueum (GSHYBE) has been used clinically to treat skin related disease in South Korea. We investigated GSHYBE-mediated changes in downstream T cell signal transduction. To determine the mechanism of inhibition, we have studied many of the major pathways in phytohemagglutinin (PHA)-activated T cell. We show that among the mitogen-activated protein kinase family activation of phosphorylation of extra cellular signal-regulated kinase 1/2 (ERK1/2, p44/42) and p38, but not c-jun NH2-terminal kinase is inhibited. In activated MOLT-4 cells, the nuclear localization of nuclear factor of activated T cells (NFATc) was blocked by GSHYBE (1 mg/ml). Also, degradation of inhibitor kappaB-alpha and transactivation by nuclear factor-kappaB (NF-kappaB)/Rel A were impaired by GSHYBE (1 mg/ml). Furthermore, interlukin (IL)-2, IL-4 and Interferen (IFN)-gamma secretion by PHA activated MOLT-4 cells and peripheral blood mononuclear cells (PBMC) were significantly diminishes following GSHYBE treatment (1 mg/ml). Also, oral administration of GSHYBE inhibited IL-2 secretion in skin allergic reaction. In conclusion, our data indicate that GSHYBE treatment of T cells inhibits ERK1/2 and p38 activation and nuclear translocation of NFATc, NF-kappaB, resulting in diminished secretion of IL-2.


Assuntos
Citocinas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Inibidores Enzimáticos/farmacologia , Imunossupressores/farmacologia , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Adulto , Sequência de Bases , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Primers do DNA , Humanos , Técnicas Imunoenzimáticas , Fatores de Transcrição NFATC
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