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The timely onset of female parturition is a critical determinant for pregnancy success. The highly heterogenous maternal decidua has been increasingly recognized as a vital factor in setting the timing of labor. Despite the cell type specific roles in parturition, the role of the uterine epithelium in the decidua remains poorly understood. This study uncovers the critical role of epithelial SHP2 in parturition initiation via COX1 and COX2 derived PGF2α leveraging epithelial specific Shp2 knockout mice, whose disruption contributes to delayed parturition initiation, dystocia and fetal deaths. Additionally, we also show that there are distinct types of epithelium in the decidua approaching parturition at single cell resolution accompanied with profound epithelium reformation via proliferation. Meanwhile, the epithelium maintains the microenvironment by communicating with stromal cells and macrophages. The epithelial microenvironment is maintained by a close interaction among epithelial, stromal and macrophage cells of uterine stromal cells. In brief, this study provides a previously unappreciated role of the epithelium in parturition preparation and sheds lights on the prevention of preterm birth.

The phyllic alteration zone is regarded as one of the most important near-surface markers in mineral exploration of porphyry deposits. The Gongpoquan and Baishantang copper deposits are two typical porphyry deposits in the Beishan metallogenic belt. A comprehensive structural and chemical study for white micas from sericitolites of these two deposits, utilizing polarized microscope, Scanning Electron Microscope (SEM), powder X-ray Diffractometer (XRD) and Electron Microprobe Analyzer (EMPA) is reported in this paper. It was discovered that both 1M polytype common sericites/muscovites and 2M1 polytype phengites co-exist in the samples. The micas occur as irregular petals, kinked platelets or straight platelets during SEM observation. According to XRD analyses, both 1M and 2M1 polytypes co-exist with different b0 values in micas, indicating their different forming conditions. The SiⅣ atoms in micas range from 3.04 to 3.37 and from 3.03 to 3.35 for Gongpoquan and Baishantang deposits, respectively, indicating the co-existence of sericites/muscovites and hydrothermal phengites. The co-existence of two types of white micas in porphyry copper deposits of the Beishan area indicate the rapid changes of ore-forming fluids from higher temperature and acidity to lower temperature and less acidity during mineralization.

Asub-micron uranium-bearing mineral in pomegranate amphibolite in the Altyn area was identified by Electron Microprobe(EPMA) and Scanning Electron Microscopy(SEM).Optical Microscope, Raman Spectroscopy and Electron Back Scattering Diffraction(EBSD) were used to study the chemical composition, occurrence state, physical and optical properties and crystal structure.Results show that this mineral is an opaque mineral closely associated with ilmenite and occurs at the edge of ilmenite.The mineral is composed of TiO2, ZrO2 and UO2 and the crystallochemical formula is(Zr, U)Ti2O6 with isomorphous substitution of U and Zr.It has a unique Raman spectrum characteristic and possibly belongs to orthorhombic system with a fersmite structure.EPMA Th-U-Pb dating of Ti-Zr-U oxide mineral yields an isochron age of 451±49 Ma, which represents the retrograde age of the host rock.Compared to the crystals which have a similar chemical composition to Ti-Zr-U oxide, the crystal structure of Ti-Zr-U oxide was found to be different from that of Srilankite, but similar to a synthetic crystal(Zr5Ti7O24) in chemical composition and crystal structure.Therefore, it is inferred that the Ti-Zr-U oxide is previously undiscovered mineral.

To separate the target group siganl in midcourse, a method based on time-frequency filtering is proposed in this paper. Firstly, the micro-motion period of one target is estimated based on the auto correlation method. Then, the signal is divided to several segments based on the estimated period. Also, the strong energy area in time-frequency domain for each segment signal is obtained by S-transform. The intersection of strong energy areas for different period can be seem as the support area of target. So, the signal attribute to one target can be obtained by time-frequency filtering based on the estimated support area. Simulation results verify the effectiveness of the proposed algorithm.

Many associated metals such as Au, Ag, Pt, Pd, and U have been found in the skarn type copper-iron deposit of Tongguanshan in Anhui. Combining microscope and Electron Microprobe (EPMA), the occurrence and distribution characteristics of these elements and calculations of the formation age of U-bearing minerals using EPMA for the first time is reported in this paper. The results show that Au exists as electrum and is related to copper sulfides and the average quality of gold is 638, indicating that gold minerals may have formed in the low temperature environment at the middle-late mineralization period. Ag occurs in different minerals and as the form of isomorphism of Cu, Te, Bi, Pb with Ag content from 74.15% to 0.12%. Pt and Pd occur as independent minerals such as platinum-bearing merenskyite. U occurs as uraninite and is associated with magnetite or occurs in the cracks of magnetite. Based on the Th-U-Pb system, the formation age of uraninite is 124±14 Ma, later than the rock (about 139 Ma), but earlier than the formation of copper and other minerals containing Au, Ag, Pt, Pb. Combining with the geological characteristics it is likely that uraninite and magnetite formed at the same time. Microscope observation shows that the paragentic sequence of minerals is garnet magnetite, uraninite, and minerals containing Au, Ag, Pt, Pd, and copper sulfides. This study provides clues for precious metal dressing, and the age of uraninite can constrain the formation age of the associated precious metals.

As a new type of displacement sensor, grating eddy current displacement sensor (GECDS) combines traditional eddy current sensors and grating structure in one. The GECDS performs a wide range displacement measurement without precision reduction. This paper proposes an analytical modeling approach for the GECDS. The solution model is established in the Cartesian coordinate system, and the solving domain is limited to finite extents by using the truncated region eigenfunction expansion method. Based on the second order vector potential, expressions for the electromagnetic field as well as coil impedance related to the displacement can be expressed in closed-form. Theoretical results are then confirmed by experiments, which prove the suitability and effectiveness of the analytical modeling approach.

Chlorides are the most common and important solutes in liquid phase of natural fluid inclusions, but they are difficult to study by Laser Raman Microscopy (LRM) at room temperature, due to their strong ionic bonds, which are not Raman active under experimental conditions. This problem seriously hinders the utilizing of LRM in a fluid inclusion study, neither for their specific components in both vapor and liquid phases, nor for their salinity. In combination with laser Raman Spectrometry and hot and cold operation boards, Raman spectra of ice, sodium chloride hydrate and calcium chloride hydrate, which were formed by frozen NaCl-H2O and CaCl2-H2O solutions with different concentrations at low temperature (-185℃) were acquired. According to systematic analysis and comparison of Raman spectra of sodium and calcium chloride hydrates with different concentrations, an attempt was made to establish a method for salinity determination by cryogenic laser Raman Spectroscopy. Results show that the area ratios of Raman bands at about 3425 cm-1 of sodium chloride hydrates to which at about 3120 cm-1 of ice were in good correlation with prepared concentrations of NaCl-H2O solutions (r2=0.9995). Similarly, area ratios of Raman bands at about 3431 cm-1 of calcium chloride hydrates to that at about 3120 cm-1 of ice were in good correlation with prepared concentrations of CaCl2-H2O solutions, too (r2=0.9458). Reliability of this method was examined by synthetic NaCl-H2O and CaCl2-H2O inclusions, which were prepared by healing microfracture of quartz crystals under high pressure and temperature conditions when the crystals were dipped in solution of specific concentration. Inspection results show that when this method is applied to > 0.5 mol/L NaCl-H2O fluid inclusions, the accuracy is better than 20%. Meanwhile, when applied to > 0.5 mol/L CaCl2-H2O fluid inclusions, the best accuracy might reach to 5%. The results meet semi-quantitative to quantitative analysis requirements for fluid inclusions. The interior pressure of fluid inclusions might be less important in salinity determination of fluid inclusions by cryogenic Raman Spectroscopy. The Raman bands of ice were somewhat different to those acquired by most other researchers (at about 3120 cm-1 in this study), which is most likely due to different polymorphs formed under the experimental condition. This method allows knowledge of the main fluid system to be attained as well as the salinity of fluid inclusions semi-quantitatively to quantitatively, with improved accuracy over traditional techniques.

In recent years, due to the similar appearance of Chicken-blood stone, red cinnabar jade has been a research concern of mineral composition, lithology and other related aspects in Jilin, Guizhou, Qinghai and other places. To investigate this further, mineralogical and gemological research has been conducted on cinnabar jade in Xunyang, Shaanxi Province, by means of normal gem conventional determination, Polarizing Microscope, X-ray Powder Diffraction (XRD), Laser Raman Spectrometer (LRS) and Electron Probe (EP). The main mineral compositions of the samples are quartz and cinnabar, with minor calcite, dolomite, barite and pyrite. The color of cinnabars becomes darker with the increase of iron content. The mineral textures are mainly clastic, granular and interpenetration metasomatic. Both the red cinnabar jade samples and bloodstone contain cinnabar, leading to their similarity in appearance. Moreover, there are obvious differences in deposit genesis and mineral composition between them. Cinnabar jade in Xunyang belongs to sedimentary-hydrothermal-strongly alteration ore deposit. The matrix of the samples is quartz, and the phenocryst is cinnabar. Chicken-blood stone of Changhua in Zhejiang Province and Balin in Mongolia Province are found in secondary fractures of Mesozoic metasomatic acidic volcanic rocks and the matrix minerals are dickite, kaolinite and pyrophyllite, with the same phenocryst of cinnabar as the samples used in this study.