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Nano-clusters based materials have received increasing attention as smart materials owing to their unique optical, electronic properties, which make their promising for a wide range of applications, such as catalysis, sensors, and drug delivery, which will expand the science of clusters. A lot of efforts have been devoted to preparing nano-scale materials with controllable size and structure in order to achieve enhanced performances in certain applications. Mass spectrometry has been widely used for characterization of clusters with different m/z . Ion mobility spectrometry combined with mass spectrometry (IM-MS) is a new technique for characterization of mental nano-clusters, which can provide the information of both structure and m/z. In this review, we compared the advantages and disadvantages between IM-MS and single crystal diffraction, nuclear magnetic resonance spectroscopy, infrared spectroscopy. The principles of different IMS including travelling-wave ion mobility spectrometry, drift tube ion mobility spectrometry and differentia mobility spectrometry were introduced. Then, the structures of different commercial IM-MS were summarized and their applications for the characterization of nanocluster were introduced, which would help to expand the ion-chemistry of atomically precise clusters. The formation of ligated metal clusters through solution-phase chemical reduction is of interest due to their sizes and structures with tunable properties. Possible isomers in ligand protected Au and Ag cluster ions have been selectively detected and identified by ion mobility mass spectrometry. The structures for vanadium oxide cluster, chromium oxide cluster, nickel oxide cluster, cerium oxide cluster, titanium oxide cluster were investigated and confirmed based on the comparisons between the measured collision cross section and the theoretical simulation. Finally, the development tendency in future were discussed and prospected. Possible tendency was suggested as following: 1) IM-MS with higher resolution should be developed to measure the size and structure of metal clusters especially for isomers. 2) For the preparation of metal cluster with size and structure selected, the clusters with special property can be obtained through the combination of IM-MS with soft deposition device, the properties of such isomers and the insights they provide on the chemistry of monolayer-protected clusters would be subjects of a future study. 3) Comparing both experimental and theoretical collision cross section would aid in characterizing clusters and exploration of the dynamic equilibrium between isomer with different structures. 4) The relationship between the structure of metal cluster and the measured reduced mobility should be investigated and the corresponding fundamental database should be set up.

Two hundred eighteen PM 10 and 202 PM 2.5 samples were collected at three sampling sites to study the pollution characteristics of carbonaceous aerosols in Yulin from July 2015 to March 2016. Organic carbon (OC) and elemental carbon (EC) in the PM 10 and PM 2.5 samples were analyzed by a Multiwavelength Thermal/Optical Carbon Analyzer, and the characteristics, including pollution levels, temporal and spatial distributions, and possible sources of OC and EC, were investigated. The results showed that the OC and EC mass concentrations in PM 10 in Yulin were 10.99 and 5.11 μg·m -3 , respectively, while the OC and EC mass concentrations in PM 2.5 were 7.51 and 4.70 μg·m -3 , respectively. Strong correlations between OC and EC were found in PM 10 ( R 2 =0.58) and PM 2.5 ( R 2 =0.60). The winter average concentrations of secondary organic carbon (SOC) in PM 10 and PM 2.5 were 14.50 μg·m -3 and 6.74 μg·m -3 , respectively. The SOC/OC ratios in both the PM 10 and PM 2.5 were higher than 0.5. The contribution of SOC to OC was 80.6% in PM 10 and 77.7% in PM 2.5 , which were the highest in the summer, in accordance with the high temperature and strong solar radiation in the summer.

Distribution characteristics, chemical constituents, and sources of particulate matter were measured using a scanning mobility particle sizer and single particle aerosol mass spectrometer during pollution monitoring that occurred between December 5 th and December 11 th , 2016, in Nanning. Results showed that particulate matter (PM) sized between 20 nm-10 μm were concentrated in the 23 to 395 nm range, with a peak of 100 nm. Three new particle types were generated during the course of this monitoring. These new 30 nm particles came into existence between 14:00 to 18:00, and grew to a size of between 40 nm and 110 nm between 20:00 to 06:00 the next day. The generation of the all three new particles was affected by motor vehicle exhaust emissions. Many secondary particles were also produced during this period of pollution. The source of the fine particulate matter was mainly from the burning of biomass, dust, and the combustion of coal. In addition, a long-distance transmission also contributed to the particles from biomass burning.

To study the chemical composition and pollution sources of the fine particulate matter during the four seasons in Nanning, single particle aerosol mass spectrometry was performed to characterize the fine particulate matter in Nanning during the four seasons. The correlation ( R 2 ) between the fine particulate matter number concentration and the mass concentration of the fine particulate matter obtained using SPAMS was all above 0.75 in the observation period. The particle number concentration could reflect the atmospheric pollution situation to some degree. The average mass spectrogram of the fine particulate matter reflected that secondary pollutants were more in winter and spring in Nanning. The Art-2a classification method was used to classify the chemical composition of the fine particulate matter. The results showed that the number concentration of the chemical composition and sources of pollution had differences in the four seasons. Chemical composition could reflect pollution sources. The elevated elemental carbon was positively with increasing coal combustion in winter. The elevated organic carbon was positively correlated with motor vehicle source in autumn. Rich potassium particles, levoglucosan and substance were positively correlated with biomass burning source and dust in summer. The rich sodium particles and heavy metals were higher in spring. During the process of increasing pollution, the contributions of biomass and coal combustion sources were large.

Objective: To explore the effect of polydatin on the growth of TGF-β₁induced humanalveolar epithelium A549 cells and the mechanism of polydatin for inhibiting the process of epithelial-mesenchymal transition (EMT)., Methods: A549 cells in vitro cultured were randomly divided into five groups, i.e., the blank group, the control group, the low dose polydatin group, the middle dose polydatin group, the high dose polydatin group. Common culture fluid was added in A549 cells of the blank group. Five ng/mLTGF-β₁contained culture fluid was added in A549 cells of the control group. 50, 100, and 150 μmol/mL of polydatin plus 5 ng/mL TGF-β₁contained culture fluid was added in A549 cells of low, middle, and high dosepolydatin groups, respectively. Morphological changes were observed and recorded at different time points. The optimal concentration of polydatin was determined by MTT method. Protein and mRNA expressions of E-cad epithelial cell marker) and Vimentin (mesenchymal cell marker) were detected by Western blot and Real-time PCR., Results: Under inverted phase contrast microscope, A549 cells turned from previous pebble shape to fusiform shape after intervened by polydatin and TGF-β1. The intercellular space was enlargedand the intercellular connection became loose. These phenomena were more obviously seen in the control group. A549 cells were more satiated in low, middle, and high dose polydatin groups than in the control group. The EMT inhibition was most obviously seen in the middle dose polydatin group at 48 h. Protein and mRNA expressions of E-cad showed an overall descending tendency after intervened by polydatin and TGF-β1 (P < 0.05). But compared with the control group, protein and mRNA expressions of E-cad were down-regulated in a lesser amplitude in each intervened group. Besides, the tendency was more obviously seen at 48 h than at 24 h. Protein and mRNA expressions of Vimentin showed an overall up-regulating tendency. But compared with the control group, protein and mRNA expressions of Vimentin were down-regulated in a lesser amplitude in each intervened group. Besides, the tendency was more obviously seen at 48 h than at 24 h (P < 0.05). CONCLUSIONS Polydatin could inhibit TGF-β1 induced EMT process of A549 cells time- and dose-dependently. It also played roles in inhibiting pulmonary fibrosis.

Single Particle Aerosol Mass Spectrometry (SPAMS) was performed to characterize the PM2.5 in Nanning from 15 to 24 February 2015. The correlation (R2) between the PM2.5 number concentration and the mass concentration of PM2.5 obtained using SPAMS was 0.76. The particle number concentration could reflect the atmospheric pollution situation to some degree. The Art-2a classification method was used to classify the chemical composition of PM2.5. The results showed that the principal chemical constituents were elemental carbon, organic elements carbon hybrid particles, organic carbon, rich potassium particles, mineral substance, rich sodium particles, second inorganic particles, levoglucosan and other heavy metals. Among them, the composition of elemental carbon was the highest, followed by organic carbon and rich potassium particles. The particle size of 80% of PM2.5 was mainly concentrated in the range of 0.2 microm to 1.0 microm with a peak value occurring at 0. 62 microm. The particle size distribution characteristics of different chemical components were similar. The number concentration of the chemical components in PM2.5 had the same variation tread with the mass concentration of PM2.5 over time. To a certain extent, the change in chemical composition could reflect the instantaneous pollution source.

Objective: To study the effect of Flos Daturae alkaloids (FDA) on TGF-beta1-1uuuu;U epithelial-mesenchymal transition (EMT) of human pulmonary adenocarcinoma A549 cells., Methods: A549 cells in vitro cultured were randomly divided into 5 groups, i.e., the blank control group, the TGF-beta1 group, the low dose FDA group, the medium dose FDA group, and the high dose FDA group. The morphologies of A549 cells were observed. Expressions of cytokeratin (CK)-19 and alpha-smooth muscle actin (alpha-SMA) were detected by Western blot and real-time PCR at 24, 48, and 72 h, respectively., Results: A549 cells in the TGF-beta1, group turned from cobblestone to spindle shape gradually. Those in low, medium and high dose FDA groups showed similar shapes to those of the TGF-beta1 group. There was no statistical difference in the morphology of A549 cells among the 3 dose FDA groups (P > 0.05). Western blot showed that, when compared with the blank control group, the expression of CK-19 was down-regulated, but the expression of alpha-SMA was up-regulated in the TGF-beta1 group (P < 0.01). Compared with the TGF-beta1, group, the expression of CK-19 was up-regulated, but the expression of alpha-SMA was suppressed in low, medium and high dose FDA groups (P < 0.01). The CK-19 expression obviously increased, but the alpha-SMA expression was suppressed in high dose FDA group at 72 h (P < 0.01). Real-time PCR results showed, as compared with the TGF-beta1 group, the mRNA expression of CK-19 was increased, but the mRNA expression of alpha-SMA was reduced in low, medium and high dose FDA groups (P < 0.01)., Conclusions: FDA had no effect on EMT morphological changes of TGF-beta1 induced A549 cells. FDA could reverse characteristic markers of A549 cells during EMT to some extent, such as expressions of CK-19 and alpha-SMA. The expression of CK-19 (as the epithelium marker) increased and the expression of alpha-SMA (as the mesenchymal marker) was reduced. Besides, they were most obviously seen in the high dose FDA group at 72 h in a dose- and time-dependent manner.

Aim: To investigate when and why a colonoscopist should discontinue incomplete colonoscopy by himself., Methods: In this cross-sectional study, 517 difficult colonoscope insertions (Grade C, Kudo's difficulty classification) screened from 37800 colonoscopy insertions were collected from April 2004 to June 2014 by three 4(th)-level (Kudo's classification) colonoscopists. The following common factors for the incomplete insertion were excluded: structural obstruction of the colon or rectum, insufficient colon cleansing, discontinuation due to patient's discomfort or pain, severe colon disease with a perforation risk (e.g., severe ischemic colonopathy). All the excluded patients were re-scheduled if permission was obtained from the patients whose intubation had failed. If the repeat intubations were still a failure because of the difficult operative techniques, those patients were also included in this study. The patient's age, sex, anesthesia and colonoscope type were recorded before colonoscopy. During the colonoscopic examination, the influencing factors of fixation, tortuosity, laxity and redundancy of the colon were assessed, and the insertion time (> 10 min or ≤ 10 min) were registered. The insertion time was analyzed by t-test, and other factors were analyzed by univariate and multivariate logistic regression., Results: Three hundred and twenty-two (62.3%) of the 517 insertions were complete in the colonoscope insertion into the ileocecum, but 195 (37.7%) failed in the insertion. Fixation, tortuosity, laxity or redundancy occurred during the colonoscopic examination. Multivariate logistic regression analysis revealed that fixation (OR = 0.06, 95%CI: 0.03-0.16, P < 0.001) and tortuosity (OR = 0.04, 95%CI: 0.02-0.08, P < 0.001) were significantly related to the insertion into the ileocecum in the left hemicolon; multivariate logistic regression analysis also revealed that fixation (OR = 0.16, 95%CI: 0.06-0.39, P < 0.001), tortuosity (OR 0.23, 95%CI: 0.13-0.43, P < 0.001), redundancy (OR = 0.12, 95%CI: 0.05-0.26, P < 0.001) and sex (OR = 0.35, 95%CI: 0.20-0.63, P < 0.001) were significantly related to the insertion into the ileocecum in the right hemicolon. Prolonged insertion time (> 10 min) was an unfavorable factor for the insertion into the ileocecum., Conclusion: Colonoscopy should be discontinued if freedom of the colonoscope body's insertion and rotation is completely lost, and the insertion time is prolonged over 30 min.

Objective: To explore the effect of qidong huoxue decoction (QHD) on inflammatory factors and Toll-like receptor (TLR4) mRNA expressions in acute lung injury (ALI) rats., Methods: Totally 50 healthy male SD rats were randomly divided into the blank control group, the lipopolysaccharide (LPS) model group, low, middle, high dose QHD groups according to body weight, 10 rats in each group. Rats in low, middle, high dose QHD groups were intragastrically administered with QHD at 4, 8, and 16 mL/kg 24, 12 h before modeling and 12 h after modeling, respectively. Normal saline was intragastrically administered to rats in the blank control group and the LPS model group. An ALI rat model was established using intratracheal instillation of LPS. Rats were killed after 24-h modeling. Then the bronchoalveolar lavage fluid was prepared. Contents of TNF-α, IL-1β, and L-10 were detected using ELISA. TLR4 mRNA expressions were determined byreal time PCR., Results: Compared with the blank control group, contents of TNF-α, IL-1β , and IL-10 increased (P <0. 01), TLR4 mRNA expressions also increased in the LPS model group (all P <0. 01). Compared with the LPS model group, contents of TNF-α and IL-1β decreased (P <0. 05, P <0. 01), IL-10 levels increased (P <0. 01) , TLR4 mRNA expressions were also reduced (P <0. 01), in high and middle dose QHD groups. Compared with the high dose QHD group, con- tents of TNF-α and IL-1β increased in middle and low dose QHD groups (P <0. 05); IL-10 levels decreased (P <0. 05) in the low dose QHD group(P <0. 05), TLR4 mRNA expressions also increased in the low dose QHD group (P <0. 05). Compared with the middle dose QHD group, IL-10 levels was reduced, but TLR4 mRNA expressions increased in the low dose QHD group (P <0. 05)., Conclusions: QHD had the protective effect on LPS induced ALI rats. Its mechanism might be associated with inhibiting TLR4 mRNA expressions, leading to decreased pro-inflammatory cytokines such as TNF-α and IL-β, elevated anti-inflammatory cytokine IL-10, and thereby, correcting unbalanced inflammation.