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The reactions of Zn(II) salts with 4, 4ʹ-(1, 3-phenylenebis (methyleneoxy)) dibenzoic acid(pbd), 1,4-bis(imidazol-1-yl)butane (bib) and 1,10-phenanthroline (1,10-phen) co-ligands afforded two coordination polymers, [Zn(pbd)(bib)] (1) and [Zn(pbd)(1,10-phen)·4H2O] (2). The pbdcaptures the in situ generated scission product of C-O bondwith 4-(3-(hydroxymethyl)benzyloxy)benzoic acid (hbb). A new polymer of [Zn(hbb)(4,4′-bipy)](3) was also synthesized using the rigid N-donor ligand of 4,4′-bipyridine (4,4′-bpy). These polymers were characterized by IR spectroscopy, and Thermogravimetric analysis and further their structures were determined by single-crystal X-ray diffraction analysis. Compound 1 has 2D covalent network. 2 and 3 show 1D chains, which can be further interlinked into 2D supramolecular layer through π─π packing and hydrogen bonded interactions, respectively. The results indicated that 1 displayed good sensing property against most of the nitroaromatic compounds (NACs) by the decrease in its luminescent intensity. With 2,4,6-trinitrophenol (picric acid) Ksv value of 2.93 × 103 M−1 and limit of detection (LOD) of 1.24 ppm was observed. The plausible mechanism of the decline in the luminescent intensity of 1 in presence of NACs has been addressed with the help of theoretical calculations.

Ceramic matrix composites have been a promising advanced material due to its superior properties such as high strength and high temperature resistance. However, due to the high hardness and brittleness of reinforcement and matrix, the machining of this new material still needs to be solved. In this study, investigation of tool performance was conducted on SiC fiber reinforced SiC ceramic matrix composites using ultrasonic vibration assisted machining technique with taking advantages of decreasing cutting force, reducing tool wear and improving machinability. Three types of tools including PDC, brazed diamond tool and electroplated diamond tool were tested by carrying out ultrasonic vibration assisted milling-grinding experiments. The milling-grinding force, material removal volume and machined surface roughness was comparatively studied at the same machining conditions. From experimental results, it was found out that the wear mechanism of PDC and electroplated diamond tool was mainly abrasive wear and fracture of grains while pull-out of grains could be additionally found for brazed diamond tool. The PDC had a better tool performance with material removal volume being 12 times and 50.63 times as larger as that of brazed diamond tool and electroplated diamond tool respectively. It was recommended that the PDC could be used for high precision machining and brazed diamond tool could be chosen for rough machining or semi finish machining in ultrasonic vibration assisted milling-grinding SiC fiber reinforced SiC ceramic matrix composites.

The particle reinforced metal matrix composites (PRMMCs) are a new kind promising materials with attracting attentions due to its superior properties such as improved strength, low density, excellent low-temperature performance and increased wear resistance. However, it was a difficult-to-cut material due to the existence of hard ceramic particles. Ultrasonic vibration-assisted machining method has attracted many attentions in machining difficult-to-cut materials. In this study, an experimental investigation was conducted on the effect of cutting and vibration parameters on the machined surface integrity of ultrasonic vibration-assisted milling in-situ TiB2/7050Al metal matrix composites. After all experiments, surface integrity such as surface roughness, residual stress, hardness and machined defects and so on were comparatively analyzed between conventional and ultrasonic vibration-assisted cutting methods. It was found that the machined surface roughness of ultrasonic vibration-assisted milling was a little larger than that of conventional milling while the compressive residual stress of the former was greater than that of the latter. It could be found that it could obtain better machined performance when vibration frequency is 30 kHz and amplitude is 4 μm in the range of given experimental parameters.

To investigate the clinical significance of atypical squamous cells of unknown significance (ASCUS) with abnormal DNA ploidy in the early diagnosis of cervical lesions.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.(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, P0.01). But the difference between ASCUS with 1-2 abnormal DNA ploidy cells and normal DNA ploidy had no statistical significance (P0.05).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.

To investigate the expression of HER2/neu, Ki-67 and TK1 protein in meningiomas in correlation with tumor grades and recurrence.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.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 (P0.05). 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 (P0.05), whereas the atypical group had lower LI than that of the malignant group (P0.05). Higher levels of LI of Ki-67 and TK1 were correlated with higher tumor grades and recurrence of the benign meningiomas (P0.05). Expression of HER2 was positively correlated with Ki-67 and TK1 (r = 0.445, P0.01; r = 0.501, P0.01, respectively), and there was a positive correlation between Ki-67 and TK1 (r = 0.450, P0.01) 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 (P0.05). 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 (P0.05).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.