Self-Curable Synaptic Ferroelectric FET Arrays for Neuromorphic Convolutional Neural Network.

With the recently increasing prevalence of deep learning, both academia and industry exhibit substantial interest in neuromorphic computing, which mimics the functional and structural features of the human brain. To realize neuromorphic computing, an energy-efficient and reliable artificial synapse must be developed. In this study, the synaptic ferroelectric field-effect-transistor (FeFET) array is fabricated as a component of a neuromorphic convolutional neural network. Beyond the single transistor level, the long-term potentiation and depression of synaptic weights are achieved at the array level, and a successful program-inhibiting operation is demonstrated in the synaptic array, achieving a learning accuracy of 79.84% on the Canadian Institute for Advanced Research (CIFAR)-10 dataset. Furthermore, an efficient self-curing method is proposed to improve the endurance of the FeFET array by tenfold, utilizing the punch-through current inherent to the device. Low-frequency noise spectroscopy is employed to quantitatively evaluate the curing efficiency of the proposed self-curing method. The results of this study provide a method to fabricate and operate reliable synaptic FeFET arrays, thereby paving the way for further development of ferroelectric-based neuromorphic computing.

Effects of nutritional status and cognitive ability on olfactory function in geriatric patients.

OBJECTIVE: The aim of this study was to investigate the prevalence of olfactory dysfunction and evaluate the relationship between olfactory function and nutritional status, comorbidity, and the results of a neurocognitive test in geriatric patients who do not suffer from neurodegenerative disease. MATERIALS AND METHODS: A total of 45 patients who visited the Geriatric Health Center of Chungnam National University Hospital were enrolled in this study. Olfactory function was assessed using a Korean Version of Sniffin' Stick Test II. Cognitive status of all participants was assessed with the MMSE-K (Korean version of the Mini-Mental State Examination). Nutritional status was assessed with body mass index, Mini-Nutritional Assessment (MNA), and serum total protein and albumin. RESULTS: A total of 45 participants were enrolled in this study. Of these subjects, 28 were men and 17 were women, with a mean age of 71.7±5.16 years. Nine (20%) were normosmia, 13 (28.9%) were hyposmia, and 23 (51.1%) were anosmia. Thirty-six patients (80%) suffered from olfactory dysfunction (anosmia or hyposmia). MMSE score showed significant correlation with MNA score. There were significant negative correlations between age and total TDI (threshold, discrimination, and identification) score, discrimination score, identification score, and MMSE score. MMSE score showed significant correlation with discrimination score and identification score. However, MNA score did not show any significant correlation with olfactory function test results. CONCLUSION: Although olfactory function was not influenced by nutritional status, abilities of discrimination and identification of odors were associated with cognitive function in geriatric patients.

Pediatric aggressive giant cell granuloma of nasal cavity.

INTRODUCTION: Giant cell granuloma (GCG) is a non-neoplastic osseous proliferative lesion of unknown etiology. Although a benign disease process, GCG can be locally destructive. It is extremely rare to have a pediatric case of GCG occurring in the nasal cavity with intracranial invasion. PRESENTATION OF CASE: We report a case of an aggressive and recurrent giant cell granuloma with intracranial invasion in a 10 years old female patient which was completely excised with endoscopic craniofacial resection. DISCUSSION: A literature review on pathogenesis, diagnosis and management is also performed. CONCLUSION: The most common treatment for giant cell granuloma is surgery, ranging from simple curettage to resection. However, it must be completely excised in cases of aggressive and extensive lesion because of the high recurrence rate after incomplete removal.

The role of B cell Activating Factor (BAFF) expression on pathogenesis of nasal polyp in chronic rhinosinusitis with nasal polyposis.

BACKGROUND: B cells, plasma cells, and local immunoglobulins, are important as a mucosal immune barrier function, and tend to increase in patients with chronic rhinosinusitis with nasal polyposis (CRSwNP). However, their association with eosinophils' aggregation has not been fully understood. The objectives of this study was to explore whether BAFF expression in the subepithelial area in nasal polyp tissues of CRSwNP was associated with eosinophils' accumulation, and also to evaluate cells which cells produce BAFF. METHODOLOGY: Immunohistochemical and immunofluorescence staining were used to analyse expression of BAFF, CD20, immunoglobulin A (IgA) and a proliferation inducing ligand (APRIL) on nasal tissues from CRSwNP patients to control subjects. To identify the relationship between BAFF and tissue eosinophilia, CRSwNP subjects were divided into eosinophilic polyp and non-eosinophilic groups. Double immunofluorescence analysis for BAFF and CD11c or CD11b was performed to identify cells producing BAFF. RESULTS: The numbers of BAFF, CD20, and IgA-positive cells in the subepithelial area were significantly higher in the CRSwNP group (both eosinophilic polyps and non-eosinophilic polyps. There were statistically significant correlations between the number of BAFF and CD20-positive cells, CD20 and IgA-positive cells, and BAFF and IgA-positive cells. CD11b-positive were co-localized with BAFF positive cells. CONCLUSION: The subepithelial expression of BAFF was associated with increased number of B cells and plasma cells, and increased production of IgA in the patients with CRSwNP, especially eosinophilic nasal polyps. Therefore, BAFF-induced IgA production may be associated with eosinophils' aggregation and degranulation, which cause aggravation of tissue inflammation and finally polyp formation. The expression of BAFF in the subepithelial area may be associated with innate inflammatory cells (CD11b+ cells), such as monocytes, granulocytes, macrophages, and natural killer cells.

Upregulation of HGF and c-MET is associated with subclinical central lymph node metastasis in papillary thyroid microcarcinoma.

BACKGROUND: Identification of a novel biomarker of subclinical lymph node metastasis (SLNM) in papillary thyroid microcarcinoma (PTMC) could provide important clues regarding SLNM in PTMC. We evaluated the significance of HGF and c-Met expression in surgically removed tumor tissue from PTMC patients as a predictive marker of SLNM. METHODS: We analyzed the immunohistochemical relationship between HGF and c-Met expression and SLNM in 113 surgically treated PTMC patients with clinically negative nodes presurgery. In addition, we explored whether HGF/c-Met pathway activation enhanced the in vitro migration and invasion of PTC cells. RESULTS: Positive immunohistochemical HGF and c-Met staining was found in 107 (95 %) and 103 (91 %) cases, respectively. The HGF staining distribution was as follows: no staining in 6 cases, weak staining in 43, moderate staining in 55, and strong staining in 9. Of the nine cases with strong HGF staining, eight (89 %) had SLNM. The c-Met staining distribution was as follows: no staining in 10 cases, weak staining in 39, moderate staining in 59, and strong staining in 5. Of the five cases with strong c-Met staining, three (60 %) had SLNM. The presence of SLNM was strongly correlated with HGF and c-Met expression in PTMC in a univariate analysis (P < 0.05). HGF overexpression was also associated with SLNM in a multivariate analysis (P < 0.05). Stimulation with exogenous HGF and constitutive activation of c-Met enhanced the migration and invasion of PTC cells in vitro by enhancing VEGF-A expression. CONCLUSIONS: HGF/c-Met pathway activation is associated with SLNM of the central neck in PTMC.

Tumor size measured by preoperative ultrasonography and postoperative pathologic examination in papillary thyroid carcinoma: relative differences according to size, calcification and coexisting thyroiditis.

Ultrasonography (US) is a useful diagnostic modality for evaluation of the size and features of thyroid nodules. Tumor size is a key indicator of the surgical extent of thyroid cancer. We evaluated the difference in tumor sizes measured by preoperative US and postoperative pathologic examination in papillary thyroid carcinoma (PTC). We reviewed the medical records of 172 consecutive patients, who underwent thyroidectomy for PTC treatment. We compared tumor size, as measured by preoperative US, with that in postoperative specimens. And we analyzed a number of factors potentially influencing the size measurement, including cancer size, calcification and coexisting thyroiditis. The mean size of the tumor measured by preoperative US was 11.4, and 10.2 mm by postoperative pathologic examination. The mean percentage difference (US-pathology/US) of tumor sizes measured by preoperative US and postoperative pathologic examination was 9.9 ± 19.3%, which was statistically significant (p < 0.001). When the effect of tumor size (≤10.0 vs. 10.1-20.0 vs. >20.0 mm) and the presence of calcification or coexisting thyroiditis on the tumor size discrepancy between the two measurements was analyzed, the mean percentage differences according to tumor size (9.1 vs. 11.2% vs. 9.8%, p = 0.842), calcification (9.2 vs. 10.2%, p = 0.756) and coexisting thyroiditis (17.6 vs. 9.5%, p = 0.223) did not show statistical significance. Tumor sizes measured in postoperative pathology were ~90% of those measured by preoperative US in PTC; this was not affected by tumor size, the presence of calcification or coexisting thyroiditis. When the surgical extent of PTC treatment according to tumor size measured by US is determined, the relative difference between tumor sizes measured by preoperative US and postoperative pathologic examination should be considered.