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Thermal ionization mass spectrometry (TIMS) is a well-established instrumental technique for accurately analyzing isotopes of elements with low first ionization potential. However, the measurement accuracy is affected due to the existence of the mass fractionation effect. Generally, applying the external standard method or total evaporation method is the most common way to correct the mass fractionation effect. Total evaporation (TE） technology is the most conventional method for uranium major isotope ratio measurement (235U/238U) using TIMS. However, due to the strong peak tailing of the major isotopes and other factors, the measurement precision and accuracy of minor isotope ratios (234U/238U and 236U/238U) are relatively low. In this study, the modified total evaporation (MTE) method for highly precise measurement of uranium isotopes ratios by TIMS was developed based on the research of dynamic heating procedures, dynamic and static receiving procedures, peak tailing correction, efficiency calibration of collectors and mass discrimination calibration. The accuracy and reliability of the MTE method were verified with different reference materials. The experiment results showed that the yield of uranium oxide should be monitored and the related parameters should be precisely controlled to reduce the yield of uranium oxidation during measurement. This action could guarantee the effectiveness of the MTE measurement and improve the uranium samples utilization. The initial strength of 187Re+ played an important role in the ionization efficiency of uranium and the yield of uranium oxide. The optimal signal of 187Re+ should be set in the range of 0.17-0.22 V. When uranium samples with 2% 235U isotopic abundance were measured by the MTE method using TIMS, the measurement precisions of 235U/238U, 234U/238U and 236U/238U were 0.024%, 0.06%, and 0.19%, and the bias between the measured value and reference value were 0.025%, 0.19%, and 0.38%, respectively. Compared to the TE method, the MTE method showed the same precision for the 235U/238U ratio measurement. As for the MTE measurement of 234U/238U and 236U/238U ratios, the major uranium isotopes (235U and 238U) were used as an internal standard to overcome the mass fractionation effect. When the tailing effects were eliminated, the measurement precisions of 234U/238U and 236U/238U ratios were improved by 5 to 10 times. As for sample amount, the TE method generally requires the uranium amount of less than 1 μg, while 5 μg is required for the MTE method.

Current research on ancient porcelain in Hebei province is focused mainly on samples of Sui, Tang, Song and Jin Dynasty, while porcelain of the Northern Dynasties attracts little attention. This paper reports a method using X-ray Fluorescence Spectrometry (XRF) analysis, X-ray Diffraction (XRD), lithofacies analysis, water absorption test and dilatometer were to study the celadon wares excavated from the Caocun Kiln. In two samples, the contents of CaO were found to be 17.86% and 14.1%, with sintering temperatures of 1150.1℃ and 1185.2℃. In the remaining samples, the contents of PbO were no less than 42%, the water absorptions of partial samples were less than 5%, and mullite was found in the X-ray diffraction pattern. In conclusion, both celadon porcelain and lead-glaze pottery were found in the excavated artifact, which provides evidence to support the hypothesis that the Caocun kiln was one of the earliest kilns, manufacturing celadon porcelain in the north of China. The lead-glaze potteries were secondary sintered based on the sintering temperature of more than 1000℃, which was much higher than that for lead-glaze pottery. This new production technique may pave the way for tricolored glazed pottery at the Tang Dynasty. Conducting experiments such as these is helpful in the understanding of the development process of porcelains in North China.

This study aims to elucidate the underlying mechanism of Erxian Decoction(EXD) against neurogenesis impairment in late-onset depression(LOD) rats based on cerebrospinal fluid(CSF) proteomics. A total of 66 20-21-month-old male Wistar rats were randomized into naturally aged(AGED) group, LOD group, and EXD group. All rats received chronic unpredictable mild stress(CUMS) for 6 weeks for LOD modeling except for the AGED group. During the modeling, EXD group was given EXD(ig, twice a day at 4 g·kg~(-1)) and other groups received equivalent amount of normal saline(ig). After modeling, a series of behavioral tests, such as sucrose preference test(SPT), open-field test(OFT), forced swimming test(FST), and Morris water maze test(MWMT) were performed. Immunofluorescence method was used to detect the number of Ki-67/Nesti-positive cells and BrdU/DCX-positive cells in the hippocampal DG area of each group. High-concentration corticosterone(CORT) was combined with D-galactose(D-gal) to simulate the changes of LOD-related stress and aging and the proliferation and differentiation of primary neural stem cells of hippocampus in each group were observed. Data independent acquisition(DIA)-mass spectrometry(MS) was used to analyze the differential proteins in CSF among groups and bioinformatics analysis was performed to explore the biological functions of the proteins. Behavioral tests showed that sucrose consumption in SPT, total traveling distance in OFT, and times of crossing the platform in MWMT were all reduced(P<0.01) and the immobility time in FST was prolonged(P<0.01) in the LOD group compared with those in the AGED group, suggesting that LOD rats had developed depression symptoms such as anhedonia, decreased locomotor activity ability, and cognitive dysfunction. Behavioral abnormalities were alleviated(P<0.01, P<0.05) in the EXD group as compared with those in the LOD group. Immunofluorescence results demonstrated that Ki-67/Nesti-positive cells and BrdU/DCX-positive cells in the hippocampal DG area were fewer(P<0.05) in LOD group than in the AGED group, and the positive cells in the EXD group were more(P<0.05) than those in the LOD group. In vitro experiment showed that the proliferation and differentiation of primary hippocampal neural stem cells under the CORT+D-gal treatment were reduced(P<0.01). The proliferation rate of neural stem cells decreased(P<0.05) in CORT+D-gal+LOD-CSF group but increased(P<0.01) in CORT+D-gal+EXD-CSF group compared with that in the CORT+D-gal group. A total of 2 620 proteins were identified from rat CSF, with 135 differential proteins between the LOD group and AGED group and 176 between EXD group and LOD group. GDF11, NrCAM, NTRK2, and GhR were related to neurogenesis and 39 differential proteins were regulated by both LOD and EXD. EXD demonstrated obvious anti-LOD effect, as it improved the locomotor activity ability and cognitive function of LOD rats and protected the proliferation and differentiation of hippocampal neural stem cells. EXD exerts anti-LOD effect by regulating the proteins related to neurogenesis in CSF, such as GDF11, NrCAM, NTRK2, and GhR and maintaining hippocampal neurogenesis.

The "Kraak Porcelain" was a kind of Blue and White Porcelain which exported from China to Europe in Ming and Qing period. The study of Kraak Porcelain is a focus issue in international field of porcelain research. In 2007, the discovery of "Nan'ao I" Shipwreck of Ming Dynasty and the porcelains loaded in it, provided precious materials for the research on Kraak Porcelain. In this paper, we explored the provenance of 10 Kraak Porcelain samples from Nan'ao I, using both traditional visual method and WDXRF.

Qumazi is a commonly used Tibetan medicine. With a long history, it can be found in the Four Medical Tantras written by gYu-thog rNying-ma Yon-tan mGon-po since the 8th century AD. Qumazi grows in mudflats and fields, including species growing in highlands, lowlands, mountains and farmlands. According to records in Crystal Beads Materia Medica, it features green sword-shaped leaves, thin stems with red veins, inserted panicles, white chicken-like flowers and copper needle row-like roots. However, there are many inconsistent morphological descriptions for Qumazi plants in many Chinese versions of Tibetan medicine books. In this article, after studying ancient and modern Tibetan medicine books, consulting experts and conducting surveys, the authors confirmed that Qumazi belongs to Rheum of Polygonaceae, including Rheum nobile Hook. f. et. Thoms, R. globulosum Gage, R. alexandrae Hook. f. et. Thoms, R. pumilum Maxim and R. delavayi Franch. In some regions, Qumazi is substituted by R. spiciforme Royle and R. przewalskyi Losinsk. After the Chinese version of Qinghai-Tibet Plateau Drug Illustrations was published in 1972, Qumazi has been miswritten as P. sibiricum Laxm in many Chinese versions of Tibetan medicine books, perhaps because P. sibiricum Laxm has many similar features with Qumazi as described in Crystal Beads Materia Medica and then is mistranslated from Tibetan to Chinese versions. According to records, Qumazi can reduce edema and is mainly applied to treat the minamata disease in clinic.

ICP-AES was used to determine the elemental composition of solutions in different conservation steps for understanding the impact of cleaning agents on ceramics from Huaguangjiao I shipwreck. The results showed that high content in solution of Al, Fe, Mg ions, which can be indexes to reflect the damage in conservation of ceramics. According to these indexes, we discovered that agents of strong cleaning ability bring more damage to ceramic samples. Meanwhile, the state of preservation of the ceramics was closely related to the damage in conservation. Ceramics in an excellent state of preservation endure less damage than that in bad state. We also found that each cleaning agent cause certain degree of damage on porcelains, even neutral reagent, like deionized water. Moreover, moderate cleaning reagent, when using a long time, bring the same degree of damage as the strong acid. Therefore, in actual protection procedure, for conservation ceramics safe and effective, damage of each cleaning agents and cumulative damage should be considered.

Titania nanotubes (TNTs) were synthesized by hydrothermal treatment of rutile-phase TiO2 nanoparticals in NaOH solution at 110 degrees C for 24 hours. After drying in aceton for 36 h, the TNTs were under vacuum drying for 24 h at room temperature. The Pt-inserted titania nanotubes (Pt/TNTs) were obtained by filling H2 PtCl6 ethanol solution into the TNTs after vacuum drying. The characterizations of the as-synthesized samples were confirmed by TEM, XRD, and UV-Vis. The photocatalytic activity of the Pt/TNTs was investigated by photo-induced decomposition of methyl orange(MO)under the main 365 nm UV-light. In order to comparison, the photocatalytic activity of both the rutile-phase TiO2 nanoparticles and pure TNTs were also investigated at the same time under the same experimental conditions. The TEM images show that the TNTs are hollow, a few hundred nanometers long, and the inner/outer diameter is about 6/10 nm. The crystal structure of TNTs is H2Ti2O5 x H2O with a little Na. Both the shape and the crystalline of the TNTs are not changed after the modification. The oval or round Pt0 nanoparticals, about 3 nm in diameter, are found only in the nanotubes. Pt/TNTs exhibit enhanced absorption at the visible range in the UV-Vis spectra and its start absorption band edge(lambda0 approximately 457 nm)is obviously redshifted compared to the rutile-phase TiO2 nanoparticals and pure TNTs. The Pt nanoparticles are found to significantly enhance the photocatalytic activity of TNTs. Pt/TNTs are demonstrated to be highly efficient for the UV-light induced photocatalytic decomposition of MO compared to both the rutile-phase TiO2 nanoparticals and pure TNTs. After irradiation for 60 min, the photocatalysis decomposition rate of MO in rutile-phase TiO2 nanoparticals, TNTs and Pt/TNTs are 46.8%, 57.2% and 84.6% respectively.

Objective: To detect the changing profiles of three factors in nasal fluid before and after endoscopic sinus surgery (ESS), including platelet derived growth factor (PDGF), tumour necrosis factor-alpha (TNF-alpha) and hyaluronic acid (HA), to investigate the predictive factor of healing quality after sinus surgery., Methods: Nasal secretions were obtained from 22 patients with nasal polyp before ESS and at 1, 4, 8, 12 weeks after ESS compared to 22 controls. Nasal fluid was analyzed by enzyme-linked immunosorbent assay (ELISA) for PDGF, TNF-alpha and HA. The healing quality was evaluated at 1, 4, 8, 12 weeks postoperatively for every one. Finally, we performed a multiple logistic regression model to assess whether the healing quality was associated with age, gender, body mass, preoperative stage, and concentrations of PDGF, TNF-alpha, HA before ESS., Results: 1. Each factor before surgery showed different level when compared to controls, PDGF was constant, TNF-alpha was high (P = 0.034), and HA was low (P = 0.003). Comparing patients at 1 week after surgery with control subjects, a significant increase in the concentrations of PDGF, TNF-alpha, HA in nasal secretions could be demonstrated (compared to controls, P = 0.000, 0.020, 0.038, respectively). After that, decreasing amounts of these factors were found, reaching normal conditions at 12 weeks for PDGF (compared to controls, P = 0.087), 8 weeks for TNF-alpha (compared to controls, P =0.104), 4 weeks for HA (compared to controls, P = 0.304). There was another peak for TNF-alpha at 12 weeks (compared to controls, P = 0.002). 2. The percentage of good healing at 1, 4, 8, 12 week postoperatively was 0, 4.5%, 36.4%, 81.8%, respectively. The healing quality after ESS was significantly and independently correlated to the age of patient and preoperative PDGF concentrations in nasal secretions. The younger, the better healing. The lower PDGF concentration, the better healing., Conclusions: During the wound healing of nasal mucosa, the levels of PDGF, TNF-alpha, HA were different at each postoperative stage. Age and PDGF concentrations preoperatively were suitable factors to predict the healing quality after ESS.