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The particle reinforced metal matrix composites have drawn attractive attentions in modern industries due to their excellent properties such as low density, improved strength, and wear resistance. However, due to the existence of hard ceramic particles, it shows poor machinability such as large cutting force and unstable machined surface quality using traditional cutting method. In this study, taking advantage of ultrasonic vibration–assisted cutting method such as reducing cutting force and improving machining quality, the machined surface integrity of a new kind of in situ TiB2/7050Al metal matrix composites was comparatively investigated between conventional milling (CM) and ultrasonic vibration–assisted milling (UVM). It was much important to match appropriate ultrasonic vibration parameters and cutting parameters for achieving a smaller surface roughness and larger surface compressive residual stress in UVM. The depth of compressive residual stress layer in the subsurface was about 90 to 120 μm, which was deeper than that of CM. Besides, ultrasonic vibration did not make obvious impact on the surface hardness and microhardness. In this paper, for ultrasonic vibration–assisted milling in situ TiB2/7050Al MMCs, the vibration parameters and cutting parameters were recommended as frequency of 30 kHz, amplitude of 4 μm, cutting speed of 30 m/min, feed rate of 0.05 mm/z, and cutting depth of 0.5 mm; the surface roughness was 0.34 μm and compressive surface residual stress was − 208 MPa. Therefore, a proper match of ultrasonic parameters and cutting parameters could significantly enhance the surface integrity in ultrasonic vibration–assisted milling in situ TiB2/7050Al MMCs. [ABSTRACT FROM AUTHOR]

A flexible wireless dielectric sensor is presented here for noninvasively monitoring the permittivity and conductivity of fluids, based on resistor–inductor–capacitor (RLC) resonant circuit and capacitively coupled contactless conductivity detection (C4D) technique. The RLC sensor consists of one single-turn inductor and one interdigital capacitor. The resonant frequency of the device is sensitive to the surrounding environment, thanks to the electric field leaked out between the interdigital capacitor electrodes. Through the high-frequency structure simulator (HFSS) simulation, and experiments on ethanol/water solutions and NaCl solutions, it was confirmed that a fluid's permittivity and conductivity could be detected by the return loss curve (S11). With great repeatability and stability, the proposed sensor has potential for broad applications, especially in wearable low-cost smart devices. [ABSTRACT FROM AUTHOR]

An all‐in‐fiber broadband photodetector is realized by integrating a micrometer‐scale multilayer graphene‐MoS2‐WS2 van der Waals heterostructure film onto a fiber facet. The device detects visible and infrared with high sensitivity and fast response. As Yi‐Feng Xiong, Yan‐Qing Lu, Fei Xu, and co‐workers report in article 1800562, the device generates photocurrent through competing photoconductive and photo‐bolometric effects. Broadband and gating‐free photodetectors and other novel optoelectronic devices could be developed from these findings. [ABSTRACT FROM AUTHOR]

Objective: To investigate the clinical significance of atypical squamous cells of unknown significance (ASCUS) with abnormal DNA ploidy in the early diagnosis of cervical lesions., Methods: Eight thousand four hundred and forty-eight patients were included in this study and all had DNA quantitative analysis and cervical liquid-based cytology. Among 1041 cases with DNA aneuploidy and/or abnormal cervical liquid-based cytology and additional cervical biopsy, histological review was performed in 247 ASCUS cases with abnormal DNA ploidy., Results: (1) Among 8448 cases, 7877 were normal or benign, 426 were ASCUS, 45 were ASC-H, 55 were LSIL and 22 were HSIL by TBS diagnosis. The presence of 1-2 abnormal DNA ploidy cells was detected in 15.3% (65/426) of ASCUS, 11.1% (5/45) of ASC-H, 9.1% (5/55) of LSIL, and 0 (0/22) of HSIL. The presence of ≥ 3 abnormal DNA ploidy cells was detected in 39.0% (166/426) of ASCUS, 75.6% (34/45) of ASC-H, 76.4% (42/55) of LSIL, and 95.5% (21/22) of HSIL. (2) A total of 67 cases of CIN 2, CIN 3 or cancers were found in 247 patients with ASCUS by colposcopy biopsies, of which 13.9% (5/36) had 1-2 abnormal DNA ploidy cells, 45.5% (56/123) had ≥ 3 abnormal DNA ploidy cells and 6.8% (6/88) had normal DNA polidy. ASCUS with 1-2 abnormal DNA ploidy cells and with ≥ 3 abnormal DNA ploidy cells were compared. The difference was statistically significant (χ(2) = 11.79, P < 0.01). But the difference between ASCUS with 1-2 abnormal DNA ploidy cells and normal DNA ploidy had no statistical significance (P > 0.05)., Conclusions: ASCUS with ≥ 3 abnormal DNA ploidy cells has higher risk for developing CIN 2, CIN 3 or invasive carcinoma. The application of DNA quantitative analysis and cervical liquid-based cytology test can help in guiding clinical follow-up and treatment options in patients with ASCUS.

Objective: To investigate the expression of HER2/neu, Ki-67 and TK1 protein in meningiomas in correlation with tumor grades and recurrence., Methods: Twenty cases of each of the following types of meningiomas were selected for the study, namely: the benign non-recurrent, recurrent benign, atypical and malignant, according to the World Health Organization (WHO) histological classification of nervous system, 2007. Immunohistochemistry study for HER2/neu, Ki-67 and TK1 protein was performed. HER2/neu gene amplification was detected using FISH. Cases with HER2 protein overexpression were studied by immunohistochemistry staining. The results of the biomarker assays were also used to study the correlationship with the tumor grades and tumor recurrency., Results: Immunohistochemistry showed that the positive rates of HER2 expression in non-recurrence benign group, recurrence benign group, atypical group and malignant group were 3 cases (15%), 6 cases (30%), 7 cases (35%), and 10 cases (50%), respectively (P < 0.05). A higher tumor grade was correlated with a higher rate of HER2/neu expression. The Ki-67 and TK1 labeling index (LI) in non-recurrence group were lower than those in the atypical or malignant group (P < 0.05), whereas the atypical group had lower LI than that of the malignant group (P < 0.05). Higher levels of LI of Ki-67 and TK1 were correlated with higher tumor grades and recurrence of the benign meningiomas (P < 0.05). Expression of HER2 was positively correlated with Ki-67 and TK1 (r = 0.445, P < 0.01; r = 0.501, P < 0.01, respectively), and there was a positive correlation between Ki-67 and TK1 (r = 0.450, P < 0.01) as well. HER2/neu gene copy amplification in 7 of 26 cases (26.9%) of HER2 immunopositive meningiomas. The rates of HER2/neu gene amplification were 0 in tumors with 1+ immunopositivity, 4/6 in tumor with 2+ immunopositivity and 3/4 in tumor with 3+ immunopositivity. HER2/neu gene amplification in 3+ and 2+ immunopositive cases had no statistical significance (P > 0.05). Aneuploidy of chromosome 17 existed in 9 of 26 of HER2 immunopositive meningiomas (34.6%). However, the rates of chromosome 17 aneuploidy had no significant difference among tumors with variable HER2/neu imumopositivity (P > 0.05)., Conclusions: High levels of HER2 and Ki-67 or TK1 expression correlate with the increase of tumor grades and tumor recurrence. HER2/neu gene amplification is seen in a subset of meningiomas with the protein expression (26.9%). A combination of biomarker study including HER2/neu, Ki-67 and TK1 may be useful in predicting the biological behavior of meningiomas.