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1.
ACS Appl Mater Interfaces ; 14(43): 48570-48581, 2022 Nov 02.
Article in English | MEDLINE | ID: mdl-36269027

ABSTRACT

Rechargeable aqueous Zn metal batteries (AZMBs) are desirable because of the advantages of metallic Zn and aqueous media. However, AZMBs suffer from limited cyclability and low Coulombic efficiency, originating from uncontrolled dendrite growth and side reactions such as hydrogen gas evolution and corrosion. A hierarchically porous poly(vinylidene difluoride) (PVDF) protection layer with ferroelectric ß-phases is formed on the Zn metal using a simple electrospinning method. This suppresses Zn metal failure modes such as side reactions and dendrite growth and supports rapid electrolyte accessibility. The synergetic effect of hierarchically porous structures and ferroelectricity not only facilitates a supporting matrix to form uniform nucleation sites for Zn deposition but also inhibits corrosion, allowing dendrite-free Zn deposition. This multifunctional PVDF film significantly improves the cyclability of Zn symmetric cells, allowing for up to 850 h of repeated plating/stripping cycles. Moreover, it exhibits an excellent cycle life of 1000 cycles under harsh conditions and high current densities of 4.0-10.0 mA cm-2, which are 62-fold higher than those that the bare Zn electrode tolerates.

2.
Korean J Radiol ; 23(11): 1031-1043, 2022 11.
Article in English | MEDLINE | ID: mdl-36126953

ABSTRACT

OBJECTIVE: To compare digital breast tomosynthesis (DBT) and MRI as an adjunct to full-field digital mammography (FFDM) for the preoperative evaluation of women with breast cancer based on mammographic density. MATERIALS AND METHODS: This retrospective study enrolled 280 patients with breast cancer who had undergone FFDM, DBT, and MRI for preoperative local tumor staging. Three radiologists independently sought the index cancer and additional ipsilateral and contralateral breast cancers using either FFDM alone, DBT plus FFDM, or MRI plus FFDM. Diagnostic performances across the three radiologists were compared among the reading modes in all patients and subgroups with dense (n = 186) and non-dense breasts (n = 94) according to mammographic density. RESULTS: Of 280 patients, 46 (16.4%) had 48 additional (39 ipsilateral and nine contralateral) cancers in addition to the index cancer. For index cancers, both DBT plus FFDM and MRI plus FFDM showed sensitivities of 100% in the non-dense group. In the dense group, DBT plus FFDM showed lower sensitivity than that of MRI plus FFDM (94.6% vs. 99.6%, p < 0.001). For additional ipsilateral cancers, DBT plus FFDM showed specificity and positive predictive value (PPV) of 100% in the non-dense group, but sensitivity and negative predictive value (NPV) were not statistically different from those of MRI plus FFDM (p > 0.05). In the dense group, DBT plus FFDM showed higher specificity (98.2% vs. 94.1%, p = 0.005) and PPV (83.1% vs. 65.4%; p = 0.036) than those of MRI plus FFDM, but lower sensitivity (59.9% vs. 75.3%; p = 0.049). For contralateral cancers, DBT plus FFDM showed higher specificity than that of MRI plus FFDM (99.0% vs. 96.7%, p = 0.014), however, the other values did not differ (all p > 0.05) in the dense group. CONCLUSION: DBT plus FFDM showed an overall higher specificity than that of MRI plus FFDM regardless of breast density, perhaps without substantial loss in sensitivity and NPV in the diagnosis of additional cancers. Thus, DBT may have the potential to be used as a preoperative breast cancer staging tool.


Subject(s)
Breast Density , Breast Neoplasms , Humans , Female , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/surgery , Retrospective Studies , Radiographic Image Enhancement , Mammography , Magnetic Resonance Imaging
4.
AJR Am J Roentgenol ; 211(5): 1068-1074, 2018 11.
Article in English | MEDLINE | ID: mdl-30160992

ABSTRACT

OBJECTIVE: The objectives of this study were to determine the diagnostic yield of percutaneous biopsy of osseous spinal lesions under CT and fluoroscopy guidance and to analyze lesion-related and technical factors affecting higher diagnostic yield. MATERIALS AND METHODS: We retrospectively reviewed 247 consecutive percutaneous spinal biopsies and recorded the following information: size, anatomic location, and bone matrix of lesions; guiding modality; years of attending physicians' experience; number of approaches; pathologic result of initial biopsy; and final diagnosis. The pathologic results of the initial biopsies were classified as diagnostic or nondiagnostic. All variables were compared using Pearson chi-square test or Fisher exact test. Multivariate logistic regression was also conducted. RESULTS: Of the initial 247 biopsies, 197 (80%) biopsies were diagnostic. On multivariate analysis, size, bone matrix, and final diagnosis of lesion were significant factors affecting biopsy yield. Biopsies of large lesions (≥ 20 mm) showed higher diagnostic yield than biopsies of small lesions (p = 0.006). Biopsies of lytic lesions had the highest diagnostic yield (88%), followed by biopsies of mixed (84%), sclerotic (67%), and isodense lesions (61%). Differences were significant for diagnostic yields of biopsies of lytic versus sclerotic lesions (p = 0.004) and lytic versus isodense lesions (p = 0.031). Biopsies of metastases had significantly highest diagnostic yield (97%), followed by biopsies of primary malignancies (84%) and benign lesions (39%) (p < 0.05). CONCLUSION: For percutaneous image-guided biopsies of spinal tumorous lesions, diagnostic yield was 80%. Size, bone matrix, and final diagnosis of lesions affected diagnostic yield of percutaneous image-guided biopsies.


Subject(s)
Image-Guided Biopsy/methods , Spinal Diseases/diagnostic imaging , Spinal Diseases/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Fluoroscopy , Humans , Male , Middle Aged , Retrospective Studies , Tomography, X-Ray Computed
5.
Korean J Radiol ; 18(1): 260-267, 2017.
Article in English | MEDLINE | ID: mdl-28096734

ABSTRACT

OBJECTIVE: Cystic fibrosis (CF) is a rare congenital disease in Korea, and its clinical and imaging findings are unclear. The objective of our study was to describe the clinical and CT features of CF in Korea and compare its features with those of other diseases mimicking CF. MATERIALS AND METHODS: From November 1994 to December 2014, a presumptive diagnosis of CF was made in 23 patients based on clinical or radiological examination. After the exclusion of 10 patients without diagnostic confirmation, 13 patients were included in the study. A diagnosis of CF was made with the CF gene study. CT findings were evaluated for the presence and distribution of parenchymal abnormalities including bronchiectasis, tree-in-bud (TIB) pattern, mucus plugging, consolidation, and mosaic attenuation. RESULTS: Of the 13 patients, 7 (median age, 15 years) were confirmed as CF, 4 (median age, 19 years) had primary ciliary dyskinesia, 1 had bronchiectasis of unknown cause, and 1 had chronic asthma. CT of patients with CF showed bilateral bronchiectasis, TIB pattern, mosaic attenuation, and mucus plugging in all patients, with upper lung predominance (57%). In CT of the non-CF patients, bilateral bronchiectasis, TIB pattern, mosaic attenuation, and mucus plugging were also predominant features, with lower lung predominance (50%). CONCLUSION: Korean patients with CF showed bilateral bronchiectasis, cellular bronchiolitis, mucus plugging, and mosaic attenuation, which overlapped with those of non-CF patients. CF gene study is recommended for the definitive diagnosis of CF in patients with these clinical and imaging features.


Subject(s)
Cystic Fibrosis/diagnosis , Adolescent , Adult , Asthma/diagnosis , Asthma/diagnostic imaging , Bronchiectasis/diagnosis , Bronchiectasis/diagnostic imaging , Child , Ciliary Motility Disorders/diagnosis , Ciliary Motility Disorders/diagnostic imaging , Cystic Fibrosis/diagnostic imaging , Female , Humans , Male , Republic of Korea , Tomography, X-Ray Computed , Young Adult
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