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The DArk Matter Particle Explorer (DAMPE) is well suitable for searching for monochromatic and sharp $\gamma$-ray structures in the GeV$-$TeV range thanks to its unprecedented high energy resolution. In this work, we search for $\gamma$-ray line structures using five years of DAMPE data. To improve the sensitivity, we develop two types of dedicated data sets (including the BgoOnly data which is the first time to be used in the data analysis for the calorimeter-based gamma-ray observatories) and adopt the signal-to-noise ratio optimized regions of interest (ROIs) for different DM density profiles. No line signals or candidates are found between 10 and 300 GeV in the Galaxy. The constraints on the velocity-averaged cross section for $\chi\chi \to \gamma\gamma$ and the decay lifetime for $\chi \to \gamma\nu$, both at 95% confidence level, have been calculated and the systematic uncertainties have been taken into account. Comparing to the previous Fermi-LAT results, though DAMPE has an acceptance smaller by a factor of $\sim 10$, similar constraints on the DM parameters are achieved and below 100 GeV the lower limits on the decay lifetime are even stronger by a factor of a few. Our results demonstrate the potential of high-energy-resolution observations on dark matter detection., Comment: 14 pages, 8 figures. Update the content to keep up with the published version

Today, approximately 10% of participants in assisted reproductive technology (ART) are defined as having recurrent implantation failure (RIF). Recent studies show that endometrial receptivity array can improve pregnancy and implantation rates by nearly 20% in women with RIF. However, these studies are limited, with little published data in the Chinese population. Recently, we have established a transcriptome-based endometrial receptivity assessment (Tb-ERA) method of predicting the endometrial window of implantation (WOI) using transcriptome-profiling data of different phases of the menstrual cycle from healthy fertile Chinese women by RNA-Seq. It is meaningful to conduct a randomized controlled trial (RCT) to assess the clinical efficiency of Tb-ERA in Chinese patients with RIF.In this RCT, a total of 200 RIF patients will be recruited and randomized into 2 groups. Patients in the Tb-ERA group will undergo a Tb-ERA test, after which embryo transfer time will be adjusted according to Tb-ERA results and embryo transfer will be performed again in the next cycle. Patients in the control group will not receive any interventions until the next transfer cycle. We will perform statistical analysis on both groups at the primary endpoint (clinical-pregnancy rate) and at secondary endpoints (rate of WOI displacement, embryo implantation, biochemical pregnancy, early abortion, and ectopic pregnancy).NCT04497558, registered August 4, 2020.

Tungsten has been considered as one of suitable candidate as plasma-facing material for the first wall of fusion devices. However, the application of tungsten in fusion reactions presents risk because of the brittleness, high ductile–brittle transition temperature, and other defects of tungsten materials. Studies have shown that ultrafine-grained/nanostructured tungsten materials can improve these problems. In its first part this article describes the powder metallurgy techniques for the preparation of ultrafine-grained/nanostructured tungsten. And the second part of this article reviews bulk processes for the preparation. The possibility of preparing ultrafine-grained/nanostructured tungsten and referenceable process parameters are described. By describing the mechanical properties and irradiation performance of ultrafine-grained/nanostructured tungsten, the research prospects and development directions of tungsten materials for fusion reactors are indicated.

Extracting the amplitude and time information from the shaped pulse is an important step in nuclear physics experiments. For this purpose, a neural network can be an alternative in off-line data processing. For processing the data in real time and reducing the off-line data storage required in a trigger event, we designed a customized neural network accelerator on a field programmable gate array platform to implement specific layers in a convolutional neural network. The latter is then used in the front-end electronics of the detector. With fully reconfigurable hardware, a tested neural network structure was used for accurate timing of shaped pulses common in front-end electronics. This design can handle up to four channels of pulse signals at once. The peak performance of each channel is 1.665 Giga operations per second at a working frequency of 25 MHz.

Obesity is a serious health challenge in the world, and searching effective drugs to cure obesity is of great importance. 1-Deoxynojirimycin (DNJ) is extracted from mulberry leaves and acts as an α-glucosidase inhibitor to lower blood glucose. Recent studies demonstrated that it also has anti-obesity effect, but the mechanisms remain unknown. In our present study, we mainly examined the effects of DNJ on beige remodeling of 3T3-L1 preadipocytes. We observed that DNJ didn't affect the mRNA levels of fatty acid binding protein 4 (aP2), peroxisome proliferator-activated receptor γ (PPARγ), preadipocyte factor-1 (Pref-1) as well as the mitochondrial uncoupling protein 1 (UCP1), PR domain containing protein 16 (PRDM16), transmembrane protein 26 (TMEM26) in undifferentiated preadipocytes. But after inducing 3T3-L1 preadipocytes to differentiation with white or beige adipogenic medium, DNJ significantly reduced aP2, PPARγ and Pref-1 expressions, while up-regulated the expressions of UCP1, PRDM16 and TMEM26, accompanying with decreased lipid deposition. The ratio of p-AMPK/AMPK was up-regulated by DNJ (10 μM) treatment for 10 days, and the effects of DNJ on p-AMPK/AMPK, UCP1 and PRDM16 could be blocked by AMPK inhibitor Compound C. These results demonstrated that hypoglycemic agent DNJ could suppress the adipogenesis during the differentiation of white preadipocytes, and promote the switch of white preadipocytes to beige adipocytes via activating AMPK, which provided new mechanisms for explaining the benefits of DNJ on obesity-related disorders.

Two three dimensional (3D) Co(II) coordination polymers incorporating similar substituted imidazole-dicarboxylate and dipyridyl-type ancillary ligands pillared layer, namely, {Co3(mimda3 −)2 (bpe)3·3H2O}n (1) and {Co3 (eimda3 −)2(bipy)3·8H2O}n (2) (H3mimda = 1H-2-methyl-4,5-imidazole-dicarboxylic acid, while H3eimda = 1H-2-ethyl-4,5-imidazole-dicarboxylic acid, bpe = 1,2-di(4-pyridyl) ethylene and bipy = 4, 4′-bipyridine) have been successfully synthesized. Both polymers 1 and 2 have been characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, and thermogravimetric analysis (TGA). X-ray structural analysis reveals that they are nearly isostructural, possessing similar symmetry units based on trinuclear clusters, and further is propagated into a Kagome-like lattice. The lattice consists of corner-sharing triangles of spins with magnetic coupling between the nearest neighboring Co(II) ions. Magnetic measurements revealed spin-canting-like antiferromagnetism behaviors for compounds 1 and 2 at lower temperature. The interaction in 1 is slightly stronger than that of 2, which can be explained by the discrepancy of organic linker between the adjacent Co(II) centers.

Neural network models show promising speed and accuracy for online and on-site data analysis in high energy physics. In this report, we discuss a multi-functional neural computing chip called PulseDL for measurement of pulse characteristics. We adopted a structure with outside RISC CPU and processing engines in PulseDL for balanced power and performance. Digital logic at register transfer level was specially designed with emphasis on thread level parallelism. Based on the hardware scheme, we co-designed the network architecture to best utilize the on-chip resources. Convolution, deconvolution and fully-connected matrix multiplication of the network were fitted into the hardware with reconfiguration during runtime. The chip has been taped out under the GSMCR013 130 nm process, with 4.9 mm × 4.9 mm area, at least 25 MHz working frequency and 1.2 V core voltage. Measured by post-layout simulations, the peak power efficiency of the chip was estimated to be about 12 giga operations per second per watt.

Solvothermal reaction of conjugated pyridine/benzene dicarboxylic acid ligand with manganese acetate in the presence of ammonium oxalate afforded a novel 2D polymer, {[Mn4(ddpp)2 (μ4-C2O4)·6H2O]·2H2O}n (ddpp = 2, 5-di(2′,4′-dicarboxylphenyl) pyridine) (1). It has been characterized by element analysis, thermogravimetry, infrared spectroscopy and single-crystal X-ray diffraction studies. Polymer 1 is constructed from tetranuclear MnII clusters through oxalate bridging, in which four adjacent MnII ions are linked into a parallelogram-core aggregate, and the polymer 1 exhibits 1D double-zigzag chains bearing a ladder-like topology feature. The ddpp ligands further interconnect these 1D double chains into 2D corrugated-shape network. Variable temperature magnetic susceptibility measurements indicate that polymer 1 exhibits weak antiferromagnetic interactions.

A new family of five new lanthanide–organic frameworks incorporating both substituted isonicotinic acid and an oxalate coligand, have been fabricated successfully through a solvo-thermal reaction, namely, {[Ln(μ2-H2minca)](μ2-C2O4)·2H2O]·mH2O}n, (Ln = Sm (1), m = 0; Eu (2), m = 1; Gd (3), m = 1; Tb (4), m = 0; Ho (5), m = 0), (H3minca = 2-(hydroxyl)-6-methyl-isonicotinic acid, H2C2O4 = oxalate acid). Complexes 1–5 are isomorphous and isostructural, and they all exhibit two dimensional (2-D) corrugated networks with 63 topology, in which {LnO8} polyhedra are linked through carboxylate and oxalate groups into a net-like sheet. The luminescence emission spectra of the complexes vary depending on which lanthanide(III) ion is present. The H2minca ligand provides efficient energy transfer for sensitization of the Eu(III) and Tb(III) complexes. Variable temperature magnetic susceptibility measurements show that compound 3 displays weak anti-ferromagnetic interactions. The magnetic behaviors of 1, 2, 4 and 5 are ascribed to the depopulation of the Stark levels and weak antiferromagnetic interactions within the lanthanide(III) complexes.

An efficient method for the construction of chiral gamma-trifluoromethylated alpha,beta-unsaturated delta-lactone, a widely existing pharmacophore, has been developed and successfully applied for synthesis of gamma-trifluoromethylated goniothalamins. The

The Xiaanxi artificial aggregate production system in Three Gorges Project is the largest one in the world by now. In the process of quarrying, the problems of serious water & soil erosion and primary ecological system injury causing by excavation and dreg have not been solved. This paper analyses the site condition of the region, and basing on it, discusses the plan of water conservation and afforestation on quarry slope, stockyard platform and tailing-dump slope. Synthetically applying different methods and technologies, it would be able to achieve the efforts of conserving water and soil as well as good ecological landscape.

Taking the method of shotcrete and rock bolt support can effectively keep slope stability and prevent soil erosion, but this method also makes the local microclimate change. This paper is to discuss the microclimate effect of revegetation on concrete slope, which take the excavated slope in Guandi hydropower station as the research object. The results show that, vegetation can significantly reduce the ground temperature and increase humidity on concrete slope, and adjust humidity changes. Especially under the conditions of high temperature in sunny day, the microclimate regulation effect of vegetation on naked slope is more obvious.

One large-diameter and non-circular steel tube was adopted in Henan TV tower (China). This special cross-section consists of three flat plates welded to three arc plates one by one. This paper studies the critical local buckling behavior of steel plates by using the finite element analysis method. Initial geometric imperfections and residual stresses presented in steel plates, material yielding and strain hardening were taken into account in the nonlinear analysis. An experimental study was performed to verify the capacity ability of this special steel tube. Based on the results obtained from the nonlinear finite element analyses and experiments, a set of design recommendations are provided for ensuring the safety of this special tube in Henan TV tower.

On the purpose of looking for better cholesterol absorption inhibitors, several trifluoromethyl substituted ezetimibe analogs 1a-d were designed and synthesized. The key steps in the synthesis of these optically pure trans-4-CF3-beta-lactams include chira

The synthesis of the first fluorine-containing analog of isoaltholactone, 5-trifluoromethylisoaltholactone (I), is described.

A stereoselective synthesis of the biologically interesting γ-monofluorinated goniothalamin analogue 2a was described. The features of the synthesis included regioselective reduction of the unprotected hydroxypropynyl moiety of compound 10 by Red-Al, asymmetric Sharpless epoxidation of allyl alcohol 11, and regio- and stereoselective ring-opening hydrofluorination of the hydroxypropynyl epoxide 14 with Et(3)N·3HF in high ee and dr. The chiral hydroxypropynyl fluorohydrin 15 was used as a valuable building block for preparation of a range of γ-monofluorinated α,β-unsaturated δ-lactones.

Background Ovarian granulosa cells are the predominant source of estradiol and progesterone biosynthesis in vivo. Rosiglitazone, a synthetic agonist of the peroxisome proliferator-activated receptor gamma (PPAR gamma), is applied as the treatment of insulin resistance including women with PCOS. The aim of the study was to investigate the direct effects of rosiglitazone on steroidogenesis and proinflammatory factor production in human granulosa-lutein cells (GLCs). Methods Primary human GLCs were separated during in vitro fertilization and cultured in the presence of rosiglitazone, GW9662 (an antagonist of PPAR gamma) and hCG. The mRNA expression of key steroidogenic factors including 3beta- hydroxysteriod dehydrogenase (3beta-HSD), cytochrome P-450 scc (CYP11A1), cytochrome P-450 aromatase (CYP19A1), and steroidogenic acute regulatory protein (StAR) were detected by quantitative real-time PCR. Estradiol and progesterone levels in GLCs cultures were measured by chemiluminescence immunoassay, and the proinflammtory factors (TNFalpha and IL-6) in conditioned culture media were measured by ELISA. Results PPAR gamma mRNA levels increased up to 3.24 fold by rosiglitazone at the concentration of 30 microM compared to control (P < 0.05). hCG alone or hCG with rosiglitazone had no significant effects on PPAR gamma mRNA levels. The CYP19A1 mRNA level at exposure to rosiglitazone alone showed a drop, but was not significantly reduced comparing to control. The expression levels of enzymes 3beta-HSD and CYP11A1 in all treatments did not alter significantly. The StAR mRNA expression at exposure to rosiglitazone was significantly increased comparing to control (P < 0.05). The media concentrations of E2 and progesterone by rosiglitazone treatment showed a declining trend comparing to control or cotreatment with hCG, which did not reach significance. Most importantly, treatment with rosiglitazone decreased TNFalpha secretion in a statistically significant manner compared with control (P < 0.05). The concentration of IL-6 following rosiglitazone exposure did not significantly decrease comparing to control. Conclusion In cultured GLCs, rosiglitazone stimulated StAR expression, but did not significantly affect steroidogenic enzymes, as well as E2 and progesterone production. Moreover, rosiglitazone significantly decreased the production of TNFalpha in human GLCs, suggesting that PPAR gamma may play a role in the regulation of GLCs functions through inhibiting proinflammatory factors.