IFKMHC: Implicit Fuzzy K-Means Model for High-Dimensional Data Clustering.

The graph-information-based fuzzy clustering has shown promising results in various datasets. However, its performance is hindered when dealing with high-dimensional data due to challenges related to redundant information and sensitivity to the similarity matrix design. To address these limitations, this article proposes an implicit fuzzy k-means (FKMs) model that enhances graph-based fuzzy clustering for high-dimensional data. Instead of explicitly designing a similarity matrix, our approach leverages the fuzzy partition result obtained from the implicit FKMs model to generate an effective similarity matrix. We employ a projection-based technique to handle redundant information, eliminating the need for specific feature extraction methods. By formulating the fuzzy clustering model solely based on the similarity matrix derived from the membership matrix, we mitigate issues, such as dependence on initial values and random fluctuations in clustering results. This innovative approach significantly improves the competitiveness of graph-enhanced fuzzy clustering for high-dimensional data. We present an efficient iterative optimization algorithm for our model and demonstrate its effectiveness through theoretical analysis and experimental comparisons with other state-of-the-art methods, showcasing its superior performance.

Adsorption and Sensing Performances of MoTe2 Monolayers Doped with Pd, Ni, and Pt for SO2 and NH3: A DFT Investigation.

Density functional theory (DFT) calculation was used to study the adsorption and sensing performances of a transition metal atom (TMA) doped MoTe2 monolayer for two industrial toxic and harmful gases, SO2 and NH3, in this study. The adsorption structure, molecular orbital, density of state, charge transfer, and energy band structure were applied to investigate the interaction between the gas and MoTe2 monolayer substrate. The conductivity of the MoTe2 monolayer film doped with TMA (Ni, Pt, Pd) is significantly improved. The original MoTe2 monolayer has poor adsorptive ability for SO2 and NH3, which is physisorption, while for the TMA-doped MoTe2 monolayer, it is significantly enhanced and the adsorption process is chemisorption. All results provide a trustworthy theoretical basis for sensors based on MoTe2 to detect toxic and harmful gases SO2 and NH3. Additionally, it also provides guidance for further research on the transition metal cluster doped MoTe2 monolayer for gas detection.

Circular RNA 0007255 regulates the progression of breast cancer through miR-335-5p/SIX2 axis.

BACKGROUND: Breast cancer (BC) is a common cancer in women worldwide. Emerging evidence has indicated that circular RNA hsa-circ_0007255 (circ_0007255) is a prognostic mediator in BC progression. However, the functional role of circ_0007255 needs to be determined. METHODS: The expression of circ_0007255, microRNA (miR)-335-5p, and SIX Homeobox 2 (SIX2) was evaluated using quantitative real-time polymerase chain reaction (qRT-PCR) or western blot assay. Actinomycin D and RNase R treatment was performed to analyze the stability of circ_0007255. Additionally, Seahorse extracellular flux, colony formation and transwell analyses were carried out to detect oxygen consumption ratio (OCR), colony formation and cell mobility, respectively. The interaction between miR-335-5p and circ_0007255 or SIX2 was confirmed via dual-luciferase reporter assay. A xenograft tumor model was established to explore the role of circ_0007255 in vivo. RESULTS: Circ_0007255 and SIX2 were overexpressed, but miR-335-5p was diminished in BC tissues and cells. Circ_0007255 absence inhibited oxygen consumption, colony formation, cell migration and invasion, and these effects were particularly abrogated via miR-335-5p upregulation in BC cells. Moreover, SIX2 deficiency eliminated the promotion effects of miR-335-5p inhibitor on oxygen consumption, colony formation, and cell mobility in BC cells. Importantly, circ_0007255 inhibited tumor growth in vivo. Mechanically, circ_0007255 was a sponge of miR-335-5p to regulate SIX2 expression in BC progression. CONCLUSION: Circ_0007255 functioned as a novel oncogene in the progression of BC by regulating miR-335-5p/SIX2 axis, and might be a promising biomarker for BC treatment. KEY POINTS: Significant findings of the study: Levels of circ_0007255 and SIX2 were upregulated, but miR-335-5p was diminished in BC tissues and cells. Circ_0007255 was an oncogene in BC development and exerted its function via miR-335-5p/SIX2 axis in BC. Tumor growth was reduced by circ_0007255 absence. WHAT THIS STUDY ADDS: Circ_0007255 functioned as a novel oncogene in the progression of BC by regulating miR-335-5p/SIX2 axis, and might be a promising biomarker for BC treatment.

18F-FDG PET/CT makes a significant contribution to diagnosis of malignancy in patients with cervical lymphadenopathy: a study using optimal scale regression tests.

BACKGROUND: The specificity and precision of lymphadenopathy assessment using US, CT and MRI are generally unsatisfactory, while fluorodeoxyglucose-positron emission tomography/computed tomography ((18)F-FDG PET/CT) can support this process by providing additional information about the lymph node features. However, which image features of (18)F-FDG PET/CT play the key role in the diagnosis and cutoffs of malignant cervical lymphadenopathy still needs to be determined by further studies. Our study aimed to identify (18)F-FDG PET/CT abnormalities that would assist in making a reliable diagnosis of malignant cervical lymphadenopathy in enlarged cervical lymph nodes of patients with unknown primary diseases. METHODS: One hundred and ninety-one consecutive patients of cervical lymphadenopathy with unknown primary causes were examined by (18)F-FDG PET/CT from May 2007 to October 2011 and a definite diagnosis was established by pathologic biopsy. (18)F-FDG PET/CT images were evaluated to identify the relevant abnormalities. All image features were analyzed by optimal scale regression tests to determine the important factors that were predictive for the diagnosis of malignant cervical lymphadenopathy and the cutoffs. RESULTS: The factors studied in (18)F-FDG PET/CT images for predicting malignant cervical lymphadenopathy were sex, age, node location, size, shape, margins, maximum standard uptake value (SUV), mean SUV, FDG uptake pattern and number of nodes. It was found that mean SUV, maximum SUV, FDG uptake pattern, location, size and margins were the important risk factors of cervical lymph nodes that could predict malignant cervical lymphadenopathy. Signs of mean SUV ≥ 2.5 (or maximum SUV ≥ 3.5), nodular FDG uptake pattern, location of IIA, III, IV, VB, VI and VII regions, size ≥ 1.5 cm and vague margins had their optimal diagnostic accuracy (Ac) and Youden index (YI), further, combination of any three factors of these six important risk factors would led to the best diagnostic Ac of 96% and YI of 0.93. CONCLUSIONS: Signs of mean SUV, maximum SUV, FDG uptake pattern, location, size and margins of node in (18)F-FDG PET/CT imaging are important predictive factors of malignant cervical lymphadenopathy. A combination of multiple factors may yield a higher diagnostic efficacy.