627 research outputs found

    Development of a hybrid magnetic resonance/computed tomography-compatible phantom for magnetic resonance guided radiotherapy

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    The purpose of the present study was to develop a hybrid magnetic resonance/computed tomography (MR/CT)-compatible phantom and tissue-equivalent materials for each MR and CT image. Therefore, the essential requirements necessary for the development of a hybrid MR/CT-compatible phantom were determined and the development process is described. A total of 12 different tissue-equivalent materials for each MR and CT image were developed from chemical components. The uniformity of each sample was calculated. The developed phantom was designed to use 14 plugs that contained various tissue-equivalent materials. Measurement using the developed phantom was performed using a 3.0-T scanner with 32 channels and a Somatom Sensation 64. The maximum percentage difference of the signal intensity (SI) value on MR images after adding K2CO3 was 3.31%. Additionally, the uniformity of each tissue was evaluated by calculating the percent image uniformity (%PIU) of the MR image, which was 82.18 ±1.87% with 83% acceptance, and the average circular-shaped regions of interest (ROIs) on CT images for all samples were within ±5 Hounsfield units (HU). Also, dosimetric evaluation was performed. The percentage differences of each tissue-equivalent sample for average dose ranged from -0.76 to 0.21%. A hybrid MR/CT-compatible phantom for MR and CT was investigated as the first trial in this field of radiation oncology and medical physics

    Change in Grafted Secondary Alveolar Bone in Patients with UCLP and UCLA : A Three-Dimensional Computed Tomography Study

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    Objective: To evaluate changes in the grafted bone after secondary alveolar bone graft (ABG) with iliac bone using 3-dimensional computed tomography (3D-CT). Materials and Methods: The sample consisted of 10 patients with unilateral cleft lip and palate (UCLP) and 5 patients with unilateral cleft lip and alveolus (UCLA) (mean age 10 years). 3DCT data (Sensation 10, Siemens, Munchen, Germany), which was obtained 1 month before (T0), 3 months after (T1), and 12 months (T2) after ABG, were used to measure the height, labiolingual thickness (LLT), and volume of the grafted bone using V-Works 4.0 program (Cybermed Inc, Seoul, Korea). All of the UCLA patients showed the lingual process in the cleft area at T0, but the UCLP did not. Results: During T1–T2, there was a significant decrease in height of the upper part of the grafted bone; however, volumes of both the upper and lower parts were decreased. Unilateral cleft type and presence of ULI in the cleft area did not affect the change in height and volume of the grafted bone. The resorption amount (RA) was significantly larger in the lower part than in the upper part, while the resorption rate (RR) exhibited an opposite result. In addition, there was significantly more RA in the labial side in UCLA than UCLP (P .05). There was no correlation between the initial cleft width and changes in height, LLT, and volume of the grafted bone. Conclusion: Overpacking and/or excessive condensation of the grafted bone is not necessary in UCLA with the lingual process because of the greater chance of resorption on the labial side of the grafted bone

    Fabrication and characterization of silicon wire solar cells having ZnO nanorod antireflection coating on Al-doped ZnO seed layer

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    In this study, we have fabricated and characterized the silicon [Si] wire solar cells with conformal ZnO nanorod antireflection coating [ARC] grown on a Al-doped ZnO [AZO] seed layer. Vertically aligned Si wire arrays were fabricated by electrochemical etching and, the pn junction was prepared by spin-on dopant diffusion method. Hydrothermal growth of the ZnO nanorods was followed by AZO film deposition on high aspect ratio Si microwire arrays by atomic layer deposition [ALD]. The introduction of an ALD-deposited AZO film on Si wire arrays not only helps to create the ZnO nanorod arrays, but also has a strong impact on the reduction of surface recombination. The reflectance spectra show that ZnO nanorods were used as an efficient ARC to enhance light absorption by multiple scattering. Also, from the current-voltage results, we found that the combination of the AZO film and ZnO nanorods on Si wire solar cells leads to an increased power conversion efficiency by more than 27% compared to the cells without it. © 2012 Baek et al.1

    Evaluating the effect of database inflation in proteogenomic search on sensitive and reliable peptide identification

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    Comparison of novel peptides identified from real proteogenomic databases. (DOCX 68 kb

    Characteristics and surgical outcomes of cleft palate in kabuki syndrome: a case series of 11 patients

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    Objective A significant number of patients with KS have cleft palate (CP) or submucous cleft palate (SMCP) and show delayed speech development. However, few reports have discussed the characteristics of CP in KS and the outcomes of postoperative speech development. The purpose of this study was to investigate the characteristics and surgical outcomes of CP in patients with KS, and to discuss the importance of the diagnosis of CP or SMCP. Methods We conducted a retrospective study on patients with clinically diagnosed KS who underwent palatoplasty. Clinical and surgical data were collected from patients medical records, and velopharyngeal function was evaluated using nasopharyngoscopy and speech analysis. Results In 11 cases, 5 patients had CP (45.5%) and 6 had SMCP (54.5%). Four patients who were genetically tested had a pathogenic variant of KMT2D. Seven of nine patients (77.8%) who underwent conventional palatoplasty showed velopharyngeal insufficiency and hypernasality. All patients who underwent pharyngeal flap surgery achieved velopharyngeal competency. Statistical analysis revealed a statistically significant difference in postoperative results between non-syndromic and KS patients. Conclusion Patients with SMCP may be more common than previously reported. The results showed that it is difficult to produce optimal results with conventional palatoplasty; therefore, pharyngeal flap surgery should be considered as a treatment to obtain favorable results. Pharyngeal flap surgery in patients with KS should be carefully designed based on speech evaluation and nasopharyngoscopic findings

    Surgical treatment and long-term outcomes of low-grade myofibroblastic sarcoma: a single-center case series of 15 patients

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    Abstract Background Low-grade myofibroblastic sarcoma (LGMS) is a poorly studied, rare, soft tissue sarcoma. LGMS is characterized by a low malignancy potential, tendency for local recurrence, and low likelihood of distant metastases. However, no studies have reported on the surgical treatment method and its long-term outcomes. Methods We included all patients treated for LGMS at our institution between March 2010 and March 2021. Medical charts were retrospectively reviewed to collect demographic information, as well as information about the clinical course, tumor characteristics, and outcomes. Statistical analysis was performed to identify the factors associated with the recurrence rate. Results Fifteen patients who underwent surgical treatment were enrolled in this study. There were seven cases in the upper extremities, four in the trunk area, three in the lower extremities, and one in the head and neck area. There were no metastatic cases and two cases of local recurrence. Conclusions The incidence of LGMS in the extremities or trunk may be higher than expected based on the current literature. Univariate analysis showed that local tissue invasion and surgical method could be associated with local recurrence. Although further large studies are needed to establish risk factors of local recurrence or extent of resection margins, based on our study, wide local excision under the proper diagnosis is the most important treatment
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