Search

To compare the difference in live birth rates (LBRs) between vaginal and intramuscular progesterone as luteal support in programmed vitrified-warmed blastocyst transfer cycles and to determine whether the association was moderated by overweight/obesity.Retrospective cohort study.Tertiary reproductive medicine center.Patients undergoing transfer of single vitrified-warmed blastocyst in a programmed cycle between January 2018 and June 2021.Vaginal progesterone or intramuscular progesterone as luteal support. Analysis was performed using the generalized estimating equations (GEE) framework and multivariate regression models. Interaction testing was used to determine whether overweight/obesity (body mass index of 25 or higher) moderated the association between progesterone replacement and LBRs.The primary outcome was live birth. The secondary outcomes were biochemical pregnancy, clinical pregnancy, miscarriage and total pregnancy loss.A total of 6905 programmed cycles (4616 with vaginal progesterone and 2289 with intramuscular progesterone) were included in the analysis. In the general cohort undergoing cryopreserved blastocyst transfer, the LBRs were 46.23% in vaginal progesterone group versus 48.62% in intramuscular progesterone group, respectively (OR 0.91, 95%CI 0.82-1.01; aOR 0.89, 95%CI 0.81-0.98), with a significantly increased rate of pregnancy losses in vaginal progesterone group compared with intramuscular progesterone group (22.22% versus 18.90%; OR 1.23, 95% CI 1.08-1.39; aOR 1.23, 95% CI 1.08-1.40). Among normal weight women, the LBRs among vaginal progesterone group were lower than that among intramuscular progesterone group (aOR 0.84, 95% CI 0.75-0.95). Whereas, among women with overweight/obesity, the LBRs were similar between the two groups of progesterone replacement (aOR 1.06, 95% CI 0.86-1.33). Interaction testing of routes of progesterone administration and overweight/obesity was significant (P=0.03).Luteal support with vaginal progesterone was associated with reduced LBRs compared with intramuscular progesterone for vitrified-warmed blastocyst transfer and the association was modified by maternal overweight/obesity. Further research is needed to better understand the mechanisms behind the association.

Peatlands play a crucial role in mediating the emissions of methane through active biogeochemical cycling of accumulated carbon driven by methane-metabolizing microorganisms; meanwhile, they serve as vital archives of atmospheric heavy metal deposition. Despite many edaphic factors confirmed as determinants to modulate the structure of methanotrophic and methanogenic communities, recognition of interactions among them is limited. In this study, peat soils were collected from Dajiuhu peatland to assess the presence of heavy metals, and methanotrophs and methanogens were investigated via high-throughput sequencing for functional genes mcrA and pmoA. Further analyses of the correlations between methane-related functional groups were conducted. The results demonstrated that both methane-metabolizing microorganisms and heavy metals have prominent vertical heterogeneity upward and downward along the depth of 20 cm. Pb, Cd, and Hg strongly correlated with methanotrophs and methanogens across all seasons and depths, serving as forceful factors in structural variations of methanogenic and methanotrophic communities. Particularly, Pb, Cd, and Hg were identified as excessive elements in Dajiuhu peatland. Furthermore, seasonal variations of networks among methane-related functional groups and environmental factors significantly affected the changes of methane fluxes across different seasons. Concretely, the complicated interactions were detrimental to methane emissions in the Dajiuhu peatland, leading to the minimum methane emissions in winter. Our study identified the key heavy metals affecting the composition of methane-metabolizing microorganisms and linkages between seasonal variations of methane emissions and interaction among heavy metals and methane-metabolizing microorganisms, which provided much new reference and theoretical basis for integrated management of natural peatlands.

To interpret the common symmetric peaks caused by the large-scale structure in the complex S(f) spectrum from the heterodyne Doppler reflectometry (DR) measurement in EAST, a 2D circular-shape O-mode full wave model based on the finite-difference time-domain method is built. The scattering characteristics and the influences on the DR signal from various scales are investigated. When the structure is located around the cut-off layer, a moving radial or poloidal large scale structure $k_\theta\lesssim k_{\theta,match}$ ($k_{\theta,match}$ is the theoretic wavenumber of Bragg scattering) could both generate an oscillation phase term called “phase modulation”, and symmetrical peaks in the complex S(f) spectrum. It was found that the image rejection ratio $A_{-1}/A_{+1}$ ($A_{\pm1}$ represent the amplitudes of $\pm1$ order modulation peaks) could be a feasible indicator for experiment comparison. In the case when the structure is near the cut-off layer same as experiment arrangement for the edge DR channel, the curve of $A_{-1}/A_{+1}$ versus to $k_\theta$ could be divided into three regions, weak asymmetrical range with $k_\theta/k_0\lesssim0.15$ ($k_0$ is the vacuum wavenumber), harmonics range with $0.15\lesssim k_\theta/k_0\lesssim0.4$, and Bragg scattering range $0.4\lesssim k_{\theta}/k_0\lesssim0.7$. In the case when the structure is located away from the cut-off layer, the final complex S(f) spectrum is the simple superimposing of modulation and Bragg scattering, and the modulation peaks have an amplitude response nearly proportional to the local density fluctuation, called the "propagation-route effect". Under the H-mode experiment arrangement for the core DR, a critical fluctuation amplitude $Amp(n_{e,Mod.@route})/Amp(n_{e,Tur.@MSA})\sim1.3-4.1$ ($Amp(n_{e,Mod.@route})$ refers to the pedestal large scale structure amplitude and $Amp(n_{e,Tur.@MSA})$ refers to turbulence amplitude at the main scattering area) is needed for the structure in the pedestal to be observed by the core DR measurement. The simulations are well consistent with the experimental results. These effects need to be carefully considered during the DR signal analyses as the injecting beam passing through the plasma region with large scale structures.

The Doppler reflectometer (DR), a powerful diagnostic for the plasma perpendicular velocity ($u_\perp$) and turbulence measurement has been widely used in various fusion devices. Many efforts have been put into extracting the Doppler shift from the DR signal. There are several commonly used methods for Doppler shift extraction, such as the phase derivative, the center of gravity (COG), and symmetric fitting (SFIT). However, the strong zero-order reflection component around $0 kHz$ may interfere with the calculation of the Doppler shift. To avoid the influence of the zero-frequency peak, the asymmetric fitting (AFIT) method was designed to calculate the Doppler shift. Nevertheless, the AFIT method may lead to an unacceptable error when the Doppler shift is relatively small compared to the half width at half maximum (HWHM). Therefore, an optimized method, which can remove the zero-frequency peak and fit the remaining Doppler peak with a Gaussian function, is devised to extract the Doppler shift. This method can still work reliably whether the HWHM is larger than the Doppler shift or not.

Background Intrauterine insemination (IUI) treatment is recommended in subfertile women with AFS/ASRM stage I/II endometriosis. However, the efficacy of IUI in women with ovarian endometriomas with tubal patency is uncertain. We explored the efficacy of IUI for the treatment of endometrioma-associated subfertility. Methods We performed a retrospective matched cohort study using propensity matching (PSM) analysis. Subfertile couples undergoing IUI with and without ovarian stimulation between January 1, 2015, and May 30, 2020 were reviewed. Results After PSM, 56 women with endometrioma alone were matched to 173 patients with unexplained subfertility. The per-cycle pregnancy rate (PR) was comparable between women with endometrioma-associated subfertility (n = 56, 87 cycles) and women with unexplained subfertility (n = 173, 280 cycles) (9.2% vs. 17.9%, OR 0.47; 95% CI, 0.21–1.03). Subgroup analyses based on IUI with or without stimulation also resulted in comparable results. A trend toward a lower cumulative pregnancy rates (CPRs) was seen in women with endometrioma (14.3%, 8/56) compared with women with unexplained subfertility (28.9%, 50/173), but the differences were not significant (HR 0.49; 95% CI, 0.23–1.15). However, patients with endometrioma were nearly twice as likely to converse to IVF treatment compared with those without the disease (60.7% versus 43.9%; OR 1.97; 95% CI, 1.07–3.65). Conclusion IUI may be a viable approach for subfertile women with endometrioma and no other identifiable infertility factor. More studies are needed to reassure the findings.

Propagation of whistler-mode waves in a magnetized plasma structure is investigated in the Keda linear magnetized plasma device. The magnetized plasma structure has its density peak in the center, and the background magnetic field is homogeneous along the axial direction. A whistler-mode wave with a frequency of 0.3 times of electron cyclotron frequency (f ce) is launched into the plasma structure. The wave normal angle (WNA) is about 25°, and the wavefront exhibits a wedge structure. During propagation of the whistler wave, both the propagating angle and WNA slowly approach zero, and then the wave is converged toward the center of the structure. Therefore, the wave tends to be trapped in the plasma structure. The results present observational evidence of the propagation of a whistler-mode wave trapped in the enhanced-density structure in a laboratory plasma. This trapping effect is consistent with satellite observations in the inner magnetosphere.

In this article, partial and full collapses of sawtooth activity are investigated with the high-resolution two-dimensional electron cyclotron emission (ECE) Imaging diagnostic in EAST. The partial ...

The oxygen reduction reaction (ORR) has been regarded as a bottleneck in air-cathode microbial fuel cells (MFC). Herein, transition metal oxides and silver were used in combination with a conductive and hydrophilic MXene (Ti3C2) for ORR. The transition metal oxides could facilitate oxygen adsorption and OO bond dissociation to improve the ORR catalytic performance of catalysts, and silver was capable of increasing the ORR kinetics and decreasing the activation overpotential significantly. Ti3C2–MxOy–Ag exhibited high ORR activity with a direct four-electron and indirect four-electron pathway in a neutral medium. In MFCs, the maximum power density was achieved by Ti3C2–MnO2–Ag (418.09 mW m−2), which was 41% higher than that of Ag–Ti3C2 (295.78 mW m−2) and 10.8 times that of Ti3C2 (38.89 mW m−2). This could be attributed to the synergistic effect between transition metal oxides and silver to promote ORR.

A two-color homodyne Mach–Zehnder (M–Z) optical fiber interferometer with wavelengths of 1.55 and 1.31 µm was developed for long-time measurement of line-integrated plasma electron density. A novel phase difference demodulation algorithm based on a single 3 × 3 optical coupler was implemented in a two-color optical fiber interferometer scheme for the first time. Our laboratory tests showed that this new optical fiber interferometer could determine the phase shift due to the low-frequency ambient vibration and could maintain high phase resolution measurement. The resolution of the new interferometer was less than 0.04 rad in 1000 s, corresponding to a line-averaged electron density of less than 1.0 × 1019 m−2. Actual plasma discharge experiments performed on KTX-CTI, which is a new compact torus injector (CTI) constructed at the Keda Torus eXperiment (KTX), showed that this interferometer has excellent several-second stability.

A homodyne Mach–Zehnder (M-Z) optical fiber interferometer (OFI) based on the optical coupler demodulation with 1.55 μm wavelength is firstly developed for high plasma density measurement on the theta pinch (IMP-θ) plasmas in the Institute of Modern Physics for the research on magnetic-inertial fusion. The evolutions of center line-averaged electron density in the theta pinch discharges are measured by the interferometer. The OFI is full-fiber structure and the line-average electron number density resolution is 10 18 m -2 . The minimum time resolution of OFI is 1ns, depended on the bandwidth of terminal InGaAs detectors. Finally, the dynamics of theta pinch plasmas are reported, which are analyzed from the density waveforms under different gas pressures and charging voltages of capacitor banks. It shows the OFI is a highly reliable and flexible routine high plasma density diagnostic tool for theta pinch plasmas.

Purpose A small number of risk prediction model have been previously reported to predict the infertility treatment success. While the studies of the risk prediction model for the patients with low prognosis are limited. This study aimed to construct and validate a nomogram for the prediction of cumulative live birth rate (CLBR) in patients with low prognosis from a single center database in Chinese population. Methods Clinical data of 4,395 patients with low prognosis, who received in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) therapy between 2014 and 2018, were retrieved and randomly divided into training (70%) and the external validation (30%) sets. Multivariate analysis with logistic regression model was conducted. Results Multivariate analyses showed that maternal age, body mass index (BMI), basal serum follicle-stimulating hormone (FSH) level, type of infertility, male factors, uterine factors, and usable embryos number at day 3 were risk factors for CLBR in patients with low prognosis. The area under the receiver operating characteristic curve (AUC) of the prediction model was 0.769 (95% confident interval (CI): 0.751, 0.787) in training set. The validation set presented good performance with an AUC of 0.749 (95% CI: 0.720, 0.778). In addition, Hosmer-Lemeshow chi-square value was 10.194 (P = 0.252). Conclusion We constructed and validated a nomogram for the prediction of CLBR in low prognosis patients with a single center database in Chinese population. The validated nomogram for the prediction of CLBR could be potentially applied in clinic for IVF counselling in patients with low prognosis.

IntroductionNatural cycle (NC) and hormone replacement treatment (HT) are frequently used endometrial preparation protocols prior to frozen-thawed embryo transfer in ovulatory women. It is not clear which protocol results in a higher live birth rate. It has been suggested that there is an increased risk in maternal and perinatal morbidity following HT protocol due to the lack of corpus luteum. The objective of this trial is to compare the clinical outcomes of NC and HT protocols in frozen embryo transfer.Methods and analysisCOMPETE is an open-label, single-centre, randomised controlled trial targeting to recruit 888 women, with 444 women each in two arms (1:1 treatment ratio). Women undergoing in vitro fertilisation scheduled for a frozen embryo transfer and have a regular menstrual cycle are eligible. Exclusion criteria include ovulation disorders and intrauterine adhesions. The primary outcome is live birth resulting from the first frozen embryo transfer after randomisation. Secondary outcomes include biochemical pregnancy, clinical pregnancy, multiple pregnancy, ongoing pregnancy, miscarriage, endometrial thickness, cycle cancellation, gestational diabetes mellitus, hypertensive disorders of pregnancy, antepartum haemorrhage, preterm birth, birth weight, large for gestational age, congenital anomaly and perinatal mortality. The data analysis will be following the intention-to-treat principle.Ethics and disseminationThis study has been approved by the Institutional Review Board of Northwest women’s and children’s hospital (2020008). Written informed consent will be obtained from each participant before randomisation. The results of the trial will be presented via publications.Trial registration numberChiCTR2000040640.

Due to the discrete nature of the saddle coils for the active feedback control of the plasma instabilities, the emergence of the sideband modes is inevitable. In the Keda Torus eXperiment (KTX), the edge Mirnov coils are unevenly distributed on the inner surface of the vacuum vessel to suppress the sideband modes. These arrays of the Mirnov coils are used for the feedback control system of KTX. They are also used for the magnetohydrodynamics (MHD) mode identification, which is a fundamental and significant method to distinguish and describe the plasma instabilities. A set of suitable MHD mode analysis methods has been utilized to complete the mode detection, including the spatial discrete Fourier transform (SDFT) method, the singular value decomposition (SVD) method and the Lomb periodogram method. These methods can obtain comprehensive mode information of the plasma instabilities and their results can be used as the feedback of the feedback control system. These methods have been successfully applied to detect and characterize an impulsive mode of ( $m = 1$ , $n = 0$ ) and rotating modes of ( $m = 2$ , 3, 4, $n = 1$ ) in the tokamak plasma of KTX, while the matrix decomposition technique is not applicable for KTX.

Electron density fluctuation has been measured based on the collect forward scattering method using a single-chord microwave interferometer system on the Keda Torus eXperiment (KTX) reversed field pinch. The interferometer system is a heterodyne one with two terahertz solid-state sources with frequency around 650 GHz, and the transmitted beam and forward scattering beam are received simultaneously by a Schottky planar diode mixer with sensitivity about 500 mV/mW. Constrained by the beamwidth and geometry limitation, the measurable wave vector range is $k_{w}\le 5 {\mathrm {cm}}^{-1}$ with a resolution $\Delta k\approx 2.07\,{\mathrm {cm}}^{-1}$ . MHD activities are detected via this forward scattering technique. The results are consistent with other diagnostics, such as the chord averaged electron density, the edge magnetic probe, and high-speed charge-coupled device (CCD) camera.

In addition to the magnetic confinement fusion plasma, Thomson scattering has been applied to measure electron density and temperature of low-temperature plasmas. Based on a linear magnetized plasma device, a set of Thomson scattering diagnostic system is designed to diagnose the plasma with n e = 10 18 – 10 19 m − 3 and T e = 2 – 5 eV. Due to low plasma temperature and density, this diagnostic system needs high spectral resolution and collection efficiency to meet the requirements of electron velocity distribution function measurements. Through the bench test, it is confirmed that the spectral resolution reaches 0.01 nm, and theoretical collection efficiency is high enough to obtain a Thomson scattering spectrum by 1000 accumulations.

Motivated by the need of the electron density measurement for the Keda Reconnection eXperiment (KRX) facility which is under development, an interferometer system has been designed and tested in bench. The 320 GHz solid-state microwave source with 1 mm wavelength is used to fulfill the high phase difference measurement in such low temperature plasma device. The results of the bench test show that the phase difference is accurately measured. In contrast to tens of degrees of phase shift expected to be measured on the KRX, the system noise (∼1°) is low enough for the KRX diagnostics. In order to optimize the system for better performance, we utilize the Terasense sub-THz imaging system to adjust alignment. The interferometer system has also been calibrated via changing of the optical path length controlled by the piezo inertial motor. Simultaneously, high density polyethylene thin film is introduced successfully to change a tiny phase difference and test the sensitivity of the interferometer system.

The Solar Influences Data Analysis Center (SIDC) issued a new version (version 2) of the sunspot number data in July 2015. The 13-month smoothed monthly sunspot number from the new version is used for the first time to research the relations among the feature parameters of solar cycles under the bimodal distribution for the modern era cycles (10–23), and, their physical implications are discussed. These relations are utilized to predict the maximum amplitude of solar cycle 25. Cycle 25 is predicted to start in October 2020 and reach its maximum amplitude of 168.5 ± 16.3 in October 2024, thus, it should be stronger than cycle 24 but weaker than cycle 23.

Groove plate with triangle structure has been designed and fabricated to improve the microwave transmittance in W band. The parameters of the triangle structure has been optimized via the Effective Medium Theory (EMT) and FDTD program. The antireflection surface in W band has been verified in lab, the experimental results are qualitatively consistent with the theoretical results.

A dynamo is necessary for reversed field pinch (RFP) configuration sustainment in a continuous way or oscillation cycles by self-organization. A dynamo velocity field from electrostatic drift is studied in three-dimensional (3D) equilibrium for Keda Torus eXperiment RFP plasmas in quasi-multi-helical (QMH) and quasi-single-helical (QSH) states. The 3D equilibrium reconstruction is computed by VMEC code. It is found that the electrostatic potential provides helical modulation of plasma flow in QSH states. The electrostatic potential in QMH states is processed as a superposition of limited helical harmonics, and it shows an axisymmetric pattern. Non-axisymmetric components are negligible in QMH states because of flux surface averaging of the electrostatic field and corresponding electrostatic drift flow. The electrostatic drift velocity is comparable to the total plasma drift in QSH states; this implies that the electrostatic drift may play an important role in sustaining the helical configuration in RFP plasma.

The flux of magnetic helicity characterizes how the topology of a magnetic field changes and helicity and its transport play essential roles in plasma equilibrium and instabilities in the reversed-field pinch (RFP) device configuration. Used to suppress magnetohydrodynamic instabilities effectively, the stabilizing conducting shell located at the boundary of an RFP device is always characterized by an eddy-current distribution that evolves rapidly with time. After measuring and analyzing the eddy currents on this stabilizing shell during tokamak discharges in the Keda Torus eXperiment device, the distributions of multiple physical quantities on the shell are obtained, including the magnetic fields, eddy currents, and electric fields. An experimental technique for measuring helicity flux density is demonstrated, combined with eddy-current diagnosis and these physical vectors on the boundary. How the magnetic and current helicity flux densities evolve is given by a feasible mathematical analysis, and data suggest that the plasma mediates both the generation and transport of magnetic helicity during the discharge. The experimental results of the distribution of the magnetic helicity flux densities (MHFDs) due to the instability on the boundary are given, and the average of these MHFDs over the whole boundary surface is far less than the maximum value of the MHFDs. In addition, the results of current helicity flux densities on the boundary are also presented.

A compact torus injection system, KTX-CTI, has been developed for the planned injection experiments on the Keda Torus eXperiment (KTX) reversed field pinch (RFP) device to investigate the physics and engineering issues associated with interaction between a compact torus (CT) and RFP. The key interests include fueling directly into the reactor center, confinement improvement, and the injection of momentum and helicity into the RFP discharges. The CT velocity and mass have been measured using a multichannel optical fiber interferometer, and for the first time the time evolution of the CT density profile during CT propagation is obtained. The effects of discharge parameters on the number of injected particles, CT velocity and CT density have been characterized: the maximum hydrogen CT plasma mass, m CT , is 50 μg, corresponding to 30% of the mass in a typical KTX plasma; the CT velocity exceeds 120 km s−1. It is observed for the first time that multiple CTs can be produced and emitted during a very short period (μs) in one discharge, which is significant for the future study of repetitive CT injection, even with an ultra-high frequency.

An optical fiber Mach-Zehnder interferometer at a wavelength of 1.55 µm has been developed for measurements of high electron density on compact torus (CT) plasmas with a high time resolution of 0.1 µs and high phase resolution of 6.4 × 10-4 rad. To improve density measurement accuracy, the phase noise of the interferometer has been investigated in detail and optimized. In the bench test, the interferometer was calibrated using a piezoelectric ceramic actuator with known stroke. Initial results on CT plasma show that the optical fiber interferometer provides reliable density measurements at two spatial locations and the bulk velocity of plasma can be determined by the method of time of flight.

Glaucocalyxin A (GLA), a major component isolated from Rabdosia japonica, has been proven to show anti-bacterial and anti-tumor biological characteristics according to previous studies. However, its potential effect on bladder cancer remains unknown. The present research aims to investigate the underlying mechanism in treating bladder cancer in vivo and in vitro. Cell proliferation was analyzed by CCK-8 assay and colony formation. Flow cytometry was used to measure the cell cycle distribution and apoptosis. The expressions of the cell cycle and apoptosis-related proteins were detected by western blotting and immunofluorescence staining. Meanwhile, the in vivo study was performed to evaluate the anti-tumor effect on a UMUC3 subcutaneous tumor of NOD/SCID mice model. GLA suppressed colony-formation ability, triggered G2/M arrest and promoted apoptosis of UMUC3 cells in a dose-dependent manner. Furthermore, western blotting showed that GLA downregulated the expressions of PI3K p85, p-Akt, Bcl-2, CDK1, Cyclin B1 whereas upregulated the levels of PTEN, Bax, Cleaved Caspase-3. In vivo, GLA at a dosage of 20 mg/kg significantly inhibited tumor growth compared with the control group by intraperitoneal injection. These results suggested that GLA-related G2/M arrest and apoptosis in UMUC3 cells were mediated by a suppressed PI3K/Akt signaling pathway, which regulated p21Waf1/Cip1 as well as intrinsic caspase cascade. Collectively, our observations could help to develop new drugs targeting the PI3K/Akt pathway for the treatment of bladder cancer.

Taste and odor (T & O) episodes always cause strong effects on drinking water supply system. Luanhe River diversion into Tianjin City in China is an important drinking water resource. Massive growth of a benthic filamentous cyanobacterium with geosmin production in the open canal caused a strong earthy odor episode in Tianjin. On the basis of the morphological and Molecular identification of this cyanobacterium as Oscillatoria limosa Agardh ex Gomont, the genetic basis for geosmin biosynthesis and factors influencing growth and geosmin production of O. limosa CHAB 7000 were studied in this work. A 2268-bp open reading frame,.encoding 755 amino acids, was amplified and characterized as the geosmin synthase gene (geo), followed by a cyclic nucleotide-binding protein gene (cob). Phylogenetic analysis implied that the evolution of the geosmin genes in O. limosa CHAB 7000 might involve a horizontal gene transfer event. Examination on the growth and geosmin production of O. limosa CHAB 7000 at different light intensities showed that the maximum geosmin production was observed at 10 mu mol photons m(-2)s(-1), while the optimum growth was at 60 mu,mol photons m(-2)s(-1). Under three temperature conditions (15 degrees C, 25 degrees C, and 35 degrees C), the maximum growth and geosmin production were observed at 25 C. Most amounts of geosmin were retained in cells during the growth phase, but high temperature and low light intensity increased the release of geosmin into the medium, implying that O. limosa CHAB 7000 had a high potential harm for the release of geosmin from its cells at these adverse conditions. (C) 2017 Elsevier B.V. All rights reserved.

Electron cyclotron emission imaging (ECEI), as an advanced diagnostic, provides two-dimensional (2D) images of electron temperature fluctuation in the core plasma region. The ECEI system on Experim...

Cylindrospermopsis raciborskii and its highly similar relatives Raphidiopsis species have been recognized as globally invasive and expansive filamentous cyanobacteria causing water blooms. Reports on C. raciborskii/Raphidiopsis species and their harmful metabolites such as hepatotoxic cylindrospermopsins (CYNs) in Chinese waters have been increasing, but mostly restricted to the southern regions of China. To further explore the existence and distribution of C. raciborskii in China, six water samples from Beijing city were morphologically and molecularly examined. Five samples of the six were shown to have Cylindrospermopsis filaments with straight and spiral morphotypes. PCR detection targeting on Cylindrospermopsis/Raphidiopsis specific 16S rRNA gene region also showed the positive amplification, and such amplifications were confirmed by sequencing and phylogenetic analysis. As well, three of the five Cylindrospermopsis containing samples were shown to have cyrJ — a gene of CYN synthesis gene cluster. The results represented the presence of toxic Cylindrospermopsis at the most northern line in China so far, indicating rapid expansion of this harmful invasive cyanobacterium. It is strongly suggested that the monitoring on C. raciborskii/Raphidiopsis species and their production of cylindrospermopsin should be emphasized in Beijing and even more northern parts of China.

An equilibrium field (EQ) power supply (PS) circuit using a feedback H-bridge pulse-width-modulation controller has been developed to control the plasma horizontal position and to satisfy the requi...

A massive amount of positrons (plasma positrons), produced by the collision between runaway electrons and nuclei during fusion plasma disruption, was first predicted theoretically in 2003. To help confirm this prediction, we report here the design of an experimental system to detect tokamak plasma positrons. Because a substantial amount of positrons (material positrons) are produced when runaway electrons impact plasma-facing materials, we proposed maximizing the ratio of plasma to material positrons by inserting a thin carbon target at the plasma edge as a plasma positron bombing target and producing a plasma disruption scenario triggered by massive gas injection. Meanwhile, the coincidence detection of positron annihilation photons was used to filter out the noise of annihilation photons from locations other than the carbon target and that of bremsstrahlung photons near 511 keV. According to our simulation, the overall signal-to-noise ratio should be more than 10:1.

To investigate the clinical efficacy of growth hormone (GH) in normal response patients with poor embryo quality in previous in vitro fertilization cycles. A total of 1562 infertile women w...

We report about the soft X-ray (SXR) tomography system which is being developed on Keda Torus eXperiment (KTX). The tomographic system aims at studying three dimensional effects in reversed field pinch with high plasma current, particularly in quasi-single-helicity state (QSH). The view distribution of the probes has been carefully designed to reflect the experimental constraints. Bayesian experimental design (BED) is used to optimize the signal camera location and camera opening angle, aiming at maximizing the gain information in future QSH states. The BED approach allows us to quantitatively evaluate the performance of the design, and to estimate the design robustness. The physical image of the plasma is tomographically reconstructed using Cormack approach and the reconstructed emissivity image may be compared to the emissivity model using the residual error χ. The camera location, camera opening angle, and sightline density are finally decided by quantitatively comparing diverse designs in order to achieve the best reconstruction.

Through a systematically developed theory, we demonstrate that the motion of Instanton identified in Zhang et al (2017 Phys. Plasmas 24 122304) is highly correlated to the intermittent excitation and propagation of geodesic acoustic mode (GAM) that is observed in tokamaks. While many numerical simulations have observed the phenomena, it is the first theory that reveals the physical mechanism behind GAM intermittent excitation and propagation. The preceding work is based on the micro-turbulence associated with toroidal ion temperature gradient mode, and slab-based phenomenological model of zonal flow. When full toroidal effect is introduced into the system, two branches of zonal flow emerge: the torus-modified low frequency zonal flow (TLFZF), and GAM, necessitating a unified exploration of GAM and TLFZF. Indeed, we observe that the transition from the Caviton to Instanton is triggered by a rapid zero-crossing of radial group velocity of drift wave and is found to be strongly correlated with the GAM onset. Many features peculiar to intermittent GAMs, observed in real machines, are thus identified in the numerical experiment. The results will be displayed in figures and in a movie; first for single central rational surface, and then with coupled multiple central rational surfaces. The periodic bursting first shown disappears as being replaced by irregular one, more similar to the intermittent characteristics observed in GAM experiments.