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Aims. With the next generation of large surveys poised to join the ranks of observational cosmology in the near future, it is important to explore their potential synergies and to maximize their scientific outcomes. In this study, we aim to investigate the complementarity of two upcoming space missions: Euclid and the China Space Station Telescope (CSST), both of which will be focused on weak gravitational lensing for cosmology. In particular, we analyze the photometric redshift (photo-z) measurements by combining NUV, 2006;gy bands from CSST with the VIS, Y,2006;J,2006;H bands from Euclid, and other optical bands from the ground-based Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) and Dark Energy Survey. We also consider the advantages of combining the two space observational data in simplifying image deblending. For Euclid, weak lensing measurements use the broad optical wavelength range of 550-900 nm, for which chromatic point-spread function (PSF) effects are significant. For this purpose, the CSST narrow-band data in the optical can provide valuable information for Euclid to obtain more accurate PSF measurements and to calibrate the color and color-gradient biases for galaxy shear measurements., Methods. We created image simulations, using the Hubble Deep UV data as the input catalog, for different surveys and quantified the photo-z performance using the EAZY template fitting code. For the blending analyses, we employed high-resolution HST-ACS CANDELS F606W and F814W data to synthesize mock simulated data for Euclid, CSST, and an LSST-like survey. We analyzed the blending fraction for different cases as well as the blending effects on galaxy photometric measurements. Furthermore, we demonstrated that CSST can provide a large enough number of high signal-to-noise ratio multi-band galaxy images to calibrate the color-gradient biases for Euclid., Results. The sky coverage of Euclid lies entirely within the CSST footprint. The combination of Euclid with the CSST data can thus be done more uniformly than with the various ground-based data that are part of the Euclid survey. Our studies show that by combining Euclid and CSST, we can reach a photo-z precision of sigma(NMAD)0.04 and an outlier fraction of eta 2.4% at the nominal depth of the Euclid Wide Survey (VIS24.5 AB mag). For CSST, including the Euclid Y,& 2006;J,& 2006;H bands reduces the overall photo-z outlier fraction from similar to 8.5% to 2.4%. For z & 2004;>& 2004;1, the improvements are even more significant. Because of the similarly high resolutions, the data combination of Euclid and CSST can be relatively straightforward for photometry measurements. On the other hand, to include ground-based data, sophisticated deblending utilizing priors from high-resolution space observations are required. The multi-band data from CSST are very helpful in controlling the chromatic PSF effect for Euclid VIS shear measurements. The color-gradient bias for Euclid galaxies with different bulge-to-total flux ratio at different redshifts can be well calibrated to the level of 0.1% using galaxies from the CSST deep survey.

We report the detection and follow-up of a superstellar flare GWAC 181229A with an amplitude of ΔR ∼ 9.5 mag on an M9-type star by SVOM/GWAC and the dedicated follow-up telescopes. The estimated bolometric energy E bol is (5.56–9.25) × 1034 erg, which makes the event one of the most powerful flares seen on ultracool stars. The magnetic strength is inferred to be 3.6–4.7 kG. Thanks to sampling with a cadence of 15 s, a new component near the peak time with a very steep decay is detected in the R-band light curve, followed by the two-component flare template given by Davenport et al. An effective temperature of 5340 ± 40 K is measured by fitting a blackbody shape to the spectrum in the shallower phase during the flare. The filling factors of the flare are estimated to be ∼30% and 19% at the peak time and at 54 minutes after the first detection. The detection of this particular event with large amplitude, huge emitted energy, and a new component demonstrates that high-cadence sky monitoring cooperation with fast follow-up observations is very important for understanding the violent magnetic activity.

To investigate the effect of exemestane on HHUA human endometrial carcinoma cells.The HHUA human endometrial carcinoma cells were treated with various concentrations of exemestane, and its effects on cell growth and apoptosis were investigated in vitro. The cell apoptosis was analyzed by flow cytometry and RT-PCR was used to investigate the expression of CD44s. The invasion ability of HHUA human endometrial carcinoma cells which treated with exemestane were assessed using transwell chamber model.At increasing doses of exemestane, a simultaneous increase in apoptotic subpopulations was detected when compared with group A (p0.05); the CD44s expression was found to be suppressed after the exemestane treatment. The decrease was a dose-dependent with exemestane treatment.6x10⁸ mol/L exemestane is an optimal dose to inhibit the expression of CD44s mRNA and inhibit the invasive growth of the endometrial carcinoma HHUA cells.

To investigate the expression of human long non-coding ribonucleic acid (RNA) small nucleolar RNA host gene 15 (SNHG15) in non-small cell lung cancer (NSCLC) tissues and its prognostic significance, and to study the influencing mechanism of SNHG15 on biological functions in lung cancer cell lines.The expression levels of SNHG15 in 49 pairs of lung cancer tissues and para-carcinoma tissues were detected via quantitative real-time polymerase chain reaction (qRT-PCR). The lung cancer cells were transiently transfected with small-interfering (si)-SNHG15 using RNA interference technique. The effect of si-SNHG15 on the proliferation of lung cancer cells was observed via methyl thiazolyl tetrazolium (MTT) assay, its effect on apoptosis of A549 cells was detected via Hoechst 33342 staining and flow cytometry, and its effects on invasion and migration of A549 cells were studied via wound healing assay and transwell assay.Results of qRT-PCR showed that the expression of SNHG15 in cancer tissues was increased compared with that in para-carcinoma tissues. Results of cell counting kit-8 (CCK-8) assay showed that knocking down SNHG15 could significantly inhibit the proliferation of lung cancer A549 cells. Hoechst 33342 staining and flow cytometry revealed that knocking down SNHG15 could significantly promote apoptosis of A549 cells. Wound healing assay and transwell assay revealed that knocking down SNHG15 could significantly inhibit the invasion and metastasis capacities of lung cancer A549 cells. Results of Western blotting showed that knocking down SNHG15 could inhibit the invasion and metastasis of A549 cells through inhibiting the expressions of epithelial-mesenchymal transition (EMT), matrix metalloproteinase-2 (MMP-2) and MMP-9 in cells.The expression of SNHG15 in lung cancer tissues is significantly higher than that in para-carcinoma tissues, the prognosis of patients accompanied with a high expression of SNHG15 is poor, and knockdown of SNHG15 in A549 cells can inhibit cell proliferation, invasion, and metastasis, and promote apoptosis.

A prime number p is called strong if p − 1 and p + 1 each have a large prime factor. Let x be a large positive number. We show a lower bound on the number of strong primes p between 1 and x such that p−1 and p+1 each have a prime factor larger than \({\sqrt{p}}\) .

To study the effects of metformin on streptozotocin-induced type 2 diabetes mellitus (T2DM) in rats.Wistar male rats were divided into two groups: standard diet (SD, n = 20) group and high-fat diet (HFD, n = 80) group. Twenty rats in HFD group were randomly treated with metformin (EI group). After 6 weeks, among rats in HFD group, 20 rats were intraperitoneally injected with citrate buffered saline (IR group), 20 rats treated with metformin per day for 4 weeks (LI group), and 20 rats were given nothing (DM group). Rats in SD group were injected with citrate buffered saline as normal control (NC) group. Moreover, streptozotocin (STZ) was used for inducing diabetes. The metabolic parameters, such as body weight, fasting blood glucose (FBG), fasting insulin concentration (FINS), total cholesterol (TC), total triglycerides (TG), low-density lipoprotein cholesterol (LDLC) and total bile acid (TBA) were measured.Compared with SD group, the levels of body weight, FBG, TC, LDLC, TBA and FINS and AUC (glucose) were significantly higher in HFD group. After administration of metformin, the levels of FBG, TG, TC, LDLC and TBA in DM and LI group were higher than NC group. Besides, the FBG, TG, TC, TBA and LDLC levels in EI group were higher than DM group.Metformin may help to improve the glucose and lipid metabolism by influencing the level of serum total bile acids. A combination of HFD and metformin could be effective in the treatment of rats with T2DM.

Prior studies show promising results of the gastric peroral endoscopic pyloromyotomy (G-POEM) procedure for treatment of refractory gastroparesis. One major technical challenge involved in this procedure is identifying the pyloric muscular ring (PMR). The aim of this study is to establish a reliable method for identification of the PMR during G-POEM. Fluoroscopy-guided G-POEM was performed by placing an endoclip at the 9 to 11’o clock position at the pylorus for identification of PMR. Conventional G-POEM was performed by observation of blue colored mucosa at the pylorus area as an indirect marker for PMR. The degree of the PMR identification was graded into well identified, identified, and not identified based on the appearance of the PMR. Procedure times were accurately documented. Gastroparesis cardinal symptoms index and gastric emptying scintigraphy were evaluated before and after the procedure. Fourteen patients were studied, seven underwent fluoroscopy-guided G-POEM, and seven patients underwent conventional G-POEM. All procedures achieved technical success and no adverse events occurred. In the seven patients who underwent fluoroscopy-guided G-POEM, the PMR was well identified in four patients and identified in three patients. In the seven patients who underwent conventional G-POEM, the PMR was identified in four patients and not identified in three patients. The average time to complete the fluoroscopy-guided G-POEM was significantly shorter than that of the conventional G-POEM. Fluoroscopy-guided G-POEM by placement of an endoclip at the pylorus was a reliable and safe method to direct the orientation of the submucosal tunnel, to facilitate the location of the PMR, and to shorten the procedure time.

ZnO nanorod arrays were grown on Zn substrates by an inexpensive and facile hydrothermal reaction at low temperature of 95°C. 0.1 M ZnCl2 was used as a precursor was dissolved in 100 ml of deionized water, and 2ml ammonia solution (25%) was added to the solution, it enable easily obtained arrayed ZnO nanorods. Morphology and microstructure of the ZnO nanorods was characterized. Precision impedance analyzer and quasi-static d33 measurer were employed to analyze the micro-area piezoelectric property. The resonant frequency and the piezoelectric constant of ZnO nanorod arrays are 1.09 MHz and 17 pm/V, respectively.

The goal of this study was to investigate the possible therapy mechanism of triterpene acids of Eriobotrya japonica (Thunb.) Lindl. Leaf (TAL) in alveolar macrophage (AM) of chronic bronchitis (CB) rats. CB model was established by injection of bacillus calmette guein (BCG) plus lipopolisacharide (LPS) in rats. TAL significantly inhibited the increased NO concentration, iNOS expression and phosphorylation of p38 MAPK in alveolar macrophages (AMs) of CB rats. Using in vivo test, we found that SB203580, a p38 MAPK inhibitor, (10 μM) significantly inhibited inducible nitric oxide synthase (iNOS) mRNA expression in AM. This data indicate that TAL highly decreases excessive iNOS expression and NO induction, and p38 MAPK signal transduction participates in iNOS expression and NO induction in AM of CB rats. The effect of TAL on iNOS expression in AM may be related to its inhibition of p38 MAPK signal transduction.

ZnS nanowires with heterocrystal and bicrystal structures were successfully synthesized using the DC-plasma chemical vapour deposition (CVD) method. The heterocrystalline ZnS nanowires have the zinc blende (ZB) and wurtzite (WZ) zones aligned alternately in the transverse direction but without an obvious period. The bicrystal ZnS nanowires are composed of two ZB fractions separated by a clear grain boundary along the length. Significantly, the grain boundaries in both the heterocrystal and bicrystal structures are atomically sharp without any visible lattice distortion. The effects of plasma species, ion bombardment, and silicon impurities in the formation of these distinctive structures are discussed. A defect-induced red-shift and broadening of the band-gap emission are revealed in photoluminescence (PL) and cathodoluminescence (CL) measurements.

A thin film of La0.8Sr0.2MnO3. prepared by computer-controlled laser molecular-beam epitaxy, on a single-crystal SrTiO3 substrate, has been characterized by transmission electron microscopy. Electron microdiffraction and high-resolution imaging reveal that the as-received thin film with a thickness of 200 nm is epitaxially grown on the SrTiO3(001) substrate. The microstructures in the whole film are clarified in terms of the oriented microdomains. The crystallographic relationships of these domains are discussed on the basis of an orthorhombic unit cell. Theoretical calculations based on a geometrical model that was recently proposed and applied to a number of epitaxial systems have been carried out to rationalize the present observations.

Dynamic mechanical response of a 20 vol% silicon carbide particles (SiCp) reinforced 2024 Al composite prepared by powder metallurgy techniques were studied with a split Hopkinson bar. The fracture mechanisms and the deformation microstructure were examined with Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The present results indicate that the composite has a strong SiC-Al interfacial bonding; failure of the material is mainly caused by fracture of SiC particles and tearing failure of the SiC-Al interface. This failure by interface tearing with adhesion of an aluminium layer on SiC particles on the fracture surfaces has not been reported in SiC particle-reinforced aluminium composites. High-resolution transmission electron microscopy studies showed that many of the SiC-Al interfaces have coincident site lattice structures, which are considered to make a significant contribution to the strong interfacial bonding.

Some basic quantitative analysis techniques of digitized high resolution atomic image are developed in this paper. We describe how to divide the atomic image into small independent areas with special structure information by the valley mesh segmentation method. The procedure is with regard to the bright contrast spot segmentation of atomic images. We suggest several ways for bright contrast spot localization in images. Calculation routines for peak detection and weighted local position average methods for this purpose are given. (C) 1996 Wiley-Liss, Inc.

Unexpected trails have been seen subsequent to relative bright sources in astronomical images taken with the CCD camera of the Lunar-based Ultraviolet Telescope (LUT) since its first light on the Moon's surface. The trails can only be found in the serial-direction of CCD readout, differing themselves from image trails of radiation-damaged space-borne CCDs, which usually appear in the parallel-readout direction. After analyzing the same trail defects following warm pixels (WPs) in dark frames, we found that the relative intensity profile of the LUT CCD trails can be expressed as an exponential function of the distance i (in number of pixels) of the trailing pixel to the original source (or WP), i.e., . The parameters α and β seem to be independent of the CCD temperature, intensity of the source (or WP), and its position in the CCD frame. The main trail characteristics show evolution occurring at an increase rate of ~(7.3 ± 3.6) × 10−4 in the first two operation years. The trails affect the consistency of the profiles of different brightness sources, which make smaller aperture photometry have larger extra systematic error. The astrometric uncertainty caused by the trails is too small to be acceptable based on LUT requirements for astrometry accuracy. Based on the empirical profile model, a correction method has been developed for LUT images that works well for restoring the fluxes of astronomical sources that are lost in trailing pixels.

An easy and convenient method, using the well-established microtome technique, has been developed to precision cut nanowires into nanodots of well-defined sizes and shapes. The technique allows the determination of the growth direction, the shape of the cross section, the internal atomic structure (including twinning or other stacking faults, if any) of single nanowires. In our experiments, both the coaxial structure of vertical cross section of normal silicon nanowires (SiNWs) and horizontal cross section of necklace-like SiNWs were obtained and examined under TEM.

Here, we report a form of nanostructures bicrystal nanoribbons. Zinc sulfide (ZnS) bicrystal nanoribbons were prepared via simple thermal evaporation of a powder mixture of ZnS and SiO. The product was characterized with transmission electron microscopy (TEM), high-resolution TEM, and electron energy loss spectroscopy. The ZnS bicrystal nanoribbons have widths of 50–500 nm and lengths of several tens of micrometers. Two kinds of growth direction, i.e. [−1−21] and [−1−31], have been found. The growth of the ZnS bicrystal nanoribbons was considered to involve a combination of oxide-assisted and vapor-liquid-solid processes.

One of the major problems in material science has been the difficulty in modification of the most endurable material, diamond, due to its extreme hardness and chemical inertness. Here, we report the development of a conical structure of diamond by performing bias-assisted reactive ion etching in hydrogen plasma. The diamond cones produced by this method are uniformly distributed over large areas on silicon substrates. Each cone was identified to be a single crystal with an apical angle as small as 28° and a very sharp tip (tip radii ∼2 nm). Their [001] axes are perpendicular to the substrate surface and parallel to each other. Such striking structures of individual single-crystal diamond cones and their arrays, in addition to their scientific value, may lead to a breakthrough in the design of high-performance mechanical and electronic devices.

There are racial differences in the prevalence and types of androgenetic alopecia (AGA). The prevalence of AGA has been studied in Caucasians and in some Asian people. In China, although there have been some epidemiological studies carried out in single cities or regions, no multicentre population-based study has been reported.To study the prevalence and types of AGA in China and to compare the results with those previously reported in Caucasians and in other Asian people.A community-based study was carried out in six cities of China. Subjects were interviewed face-to-face and completed questionnaires. The degree of AGA was classified according to the Norwood and Ludwig classifications.In total 17 886 subjects were interviewed and 15 257 completed the questionnaires. In men, the overall prevalence of AGA was 21.3%, with 2.8% in men aged 18-29 years, 13.3% in those aged 30-39 years, 21.4% in those aged 40-49 years, 31.9% in those aged 50-59 years, 36.2% in those aged 60-69 years and 41.4% in those aged 70 years and over. The most common type was frontal and vertex hair loss. A small number of subjects (3.7%) showed 'female pattern' hair loss. In women, the prevalence of AGA was 6.0%, with 1.3% in women aged 18-29 years, 2.3% in those aged 30-39 years, 5.4% in those aged 40-49 years, 7.5% in those aged 50-59 years, 10.3% in those aged 60-69 years and 11.8% in those aged 70 years and over. Ludwig grade I was the most common type. The prevalence of AGA varied between cities. A positive family history was present in 29.7% of men and 19.2% of women with AGA.The prevalence of AGA in Chinese men and women was lower than in Caucasians and similar to that in Koreans.

A decaprismatic growth morphology has been found for the first time for the decagonal quasicrystal in the Al65Cu20Co15 alloy slowly cooled from the melt. Substituting a little si for Al in this alloy, for example, Al62Si3Cu20Co15, results in quasicrystal decaprisms of 0·5 mm in diameter and several millimetres in length. These decaprisms showed possibly a 10/mmm morphology which was proved later by electron and X-ray single crystal diffraction analyses. Moreover, the sharp selected-area electron diffraction (SAED) and convergent-beam electron diffraction (CBED) patterns show clearly a high degree of perfection and the X-ray precession photographs prove the single crystalline nature across a few millimetres of this decagonal quasicrystal.

Molecular cloning of cardiac troponin I-interacting kinase (TNNI3K), a novel cardiac-specific protein kinase containing seven N-terminal ankyrin (ANK) repeats followed by a protein kinase domain and a C-terminal Ser-rich domain, has previously been reported. In the present study, we show that the C-terminal functional region of TNNI3K negatively regulates the kinase activity, and the N-terminal ANK domain is necessary for autophosphorylation. An in vitro kinase assay shows that TNNI3K exhibits dual-specific kinase activity and forms dimers or oligomers that may be necessary for its activation.

We present a study of the photoluminescence and lasing characteristics of individual single-crystal zinc sulfide nanoribbons. We show that ZnS presents optical gain at the near band gap emission of ∼338 nm. Optical gain together with the optical cavity defined by the perfect crystallographic structure with a rectangular cross section results in lasing activity at optical pumping power densities of ∼ 50 kW/cm2. Small collection angle measurements show that nanoribbons form excellent optical cavities and gain medium with record (FWHM

To investigate the different killing effect to human pulmonary adenocarcinoma cell line cells GLC-82 with coexpressed double suicide genes compared with single gene.Recombinant expression vectors containing CD (cytosine deaminase) and/or TK (thymidine kinase) gene under CMV promoter were constructed successfully. The vectors were transfected to GLC-82 tumor cell lines by use of lipofectamine. The clones were picked out after G418 selection. Extraneous gene integration and expression were confirmed by PCR and semi-quantitative RT-PCR. The cytotoxicity to these transgenic cells under treatment with 5-Fc and GCV were measured by MTT assays.Double and single suicide gene transfer were both stably expressed in GLC-82 cells. The cytotoxic effects of co-expressed TK-CD genes were superior than that of the single gene.The CD + TK/5-Fc + GCV co-expression system is more effective for killing effect of tumor cells than CD/5-Fc or TK/GCV system alone.

In this paper, graphene/multi-walled carbon nanotubes (GM) hybrid nanostructure was synthesized by modifying GR using salicylamide. Cu -doped ZnO nanoparticles were successfully decorated on GR/MWNTs hybrids (GM). Their photocatalytic performance for the degradation of methyl orange (MO) was investigated and the results showed that the synthetic GM/ Cu -doped ZnO hybrids exhibited better photocatalytic ability than MWNTs/ Cu -doped ZnO and GR/ Cu -doped ZnO hybrids, in which the degraded rate for 20 mg/L MO solution reaches about 100% in 45 min.

Some basic quantitative analysis techniques of digitized high resolution atomic image are developed in this paper. We describe how to divide the atomic image into small independent areas with special structure information by the valley mesh segmentation method. The procedure is with regard to the bright contrast spot segmentation of atomic images. We suggest several ways for bright contrast spot localization in images. Calculation routines for peak detection and weighted local position average methods for this purpose are given.

Compact deformation - induced martensite found in Fe - 25Ni - 0.66C alloys has been studied by using optical, electron and scanning electron microscopy. The compact martensite consists of a large number of martensites with different variants connected closely to form large bulk in which almost no residual austenite remains. Its formation process is by further growth of thin plates to form lenticular plates and possible crossing and coalesence to form bulky martensite. These growth and coalesence are through martensitic twinning or twinning domains during deformation which leads to various interactions between the plates including cross, insert, coalescence and conversion. The substructure of the martensite is a crisscross twinning net. The corresponding deformation modes of the austenite are also studied.

The pressure of the portal trunk, the left gastric vein, the left and right gastroepiploic veins, the mesenteric vein and the abdominal aorta was measured experimentally at the same time in 10 normal dogs. The levels of the raised pressure in the different compartments with their outflow tracts obstructed respectively were observed and the potentials of the functional barriers between these compartments were quantitatively evaluated. The findings showed that the average power of the functional barriers was 45.1 +/- 5.7% between the different compartments in the gastrosplenic area and 74.3% in the mesenteric region. The weakness of the functional barriers' capacity limiting the collateral diversion between the lesser and greater splanchnic systems may be one of the causes making the distal splenorenal shunt lose its selectivity.

Thermal burn on the back of rat (20% TBSA full-thickness burn) was used to study the changes in free radicals and lipid peroxidation and function of the antioxidation of erythrocytes postburn. It was found that there were increase in the concentration of lipid peroxides and decrease in activity of glutathione peroxidase (GSHpx) in plasma. The activity of RBC GSHpx increased significantly on day 1 postburn. When RBC GSHpx could not resist the injury, the function of antioxidation decreased, such as the activities of G6PD, GSHpx and the concentration of GSH and NPSH. RBC LPO increased, which cross-linked with sulfhydryl proteins and inflicted injury to RBC membrane. It might be concluded that the mechanism of damage of RBC after burn injury is due to chain reactions of free radicals and lipid peroxidation of the cell membrane. It also proved that there were changes in functional capability of antioxidation in vivo after burn injury. Further study is needed to locate the site of production of free radicals within or/and in the neighborhood of RBC and elucidate the transfer of the messages which cause the change.

Substrate temperature and chemical etching were demonstrated to be dominant factors in determining the in-plane orientation of AlN films grown epitaxially on SrTiO3 (STO) (111) substrates by magnetron sputtering. Single-domain epitaxial AlN films were grown at moderate temperatures of 270–370°C with a sharp interface and orientation relationship of [21¯1¯0]AlN∥[01¯1]STO and (0002)AlN∥(111)STO. At temperature above 470°C, an additional 30° in-plane-rotated AlN domain appeared, and increased in percentage with increasing temperature. A model based on the reconstruction of STO (111) surfaces from (1×1) to (3×3)R30° was proposed to account for the formation of this new domain.

City Univ Hong Kong, Dept Phys & Mat Sci, Hong Kong, Hong Kong. Acad Sinica, Inst Met Res, Shenyang 110015, Peoples R China.;Lu, YX (reprint author), City Univ Hong Kong, Dept Phys & Mat Sci, Tat Chee Ave, Hong Kong, Hong Kong

A simple coating technique was introduced to preserve the surface structure of samples for transmission electron microscopy (TEM) characterization, and used to study boron nitride (BN) films. A gold film precoated on the surface of BN films served to protect the BN surface against ion damages during sample preparation, and to separate and distinguish the film surface structure from the TEM glue. The technique enabled the observation of detailed surface microstructures of cubic BN (cBN) films, which provided direct evidences for understanding cBN growth mechanisms. The TEM sample technique is expected to be generally applicable to other film systems, particularly those with an amorphous topmost layer.

X-ray diffraction showed that the conventionally solidified A165Cu20 Co15 alloy consistes mainly of 2-D decagonal quasicrystal (T phase). SEM reveals that T phase formed the perfect morphology of prismoid with 10/m or 10/mmm symmetry. The bounded planes of primoid correspond to the strong spots in the electron diffraction pattern of T phase.

Electron microscopy of purified Chlamydia trachomatis treated by various physical and chemical means shows that the envelope of the elementary bodies (EB) consists of the outer cell wall layer, the inner cell wall layer, and the inner membrane. The outer cell wall layer is mainly made up of granular subunits arranged in a hexagonal pattern and may be called the "mural structural protein layer". It forms together with the inner cell wall layer the rigid cell wall. The inner or protoplasmic membrane is not easily shown in the young EB. In the negatively stained specimen, a frail and easily removable superficial layer is seen adhering to the "mural structural protein layer". But in ultra-thin sections this superficial layer is not shown separately. There are fold-like grooves which are special structures probably related to reproduction. There are seen some EB's in binary fission, and a number of bodies very big in size yet having morphological characteristics of the EB's, which are in various processes of multiplication, such as binary fission, budding, and "multicentered germination". These observations give a challenge to the current opinion that only the initial bodies have the power of reproduction.