Enhancement of electron–ion recombination rates at low energy range in the heavy ion storage ring CSRm

Recombination of Ar^(14+), Ar^(15+), Ca^(16+), and Ni^(19+) ions with electrons has been investigated at low energy range based on the merged-beam method at the main cooler storage ring CSRm in the Institute of Modern Physics, Lanzhou,China. For each ion, the absolute recombination rate coefficients have been measured with electron–ion collision energies from 0 meV to 1000 meV which include the radiative recombination(RR) and also dielectronic recombination(DR)processes. In order to interpret the measured results, RR cross sections were obtained from a modified version of the semiclassical Bethe and Salpeter formula for hydrogenic ions. DR cross sections were calculated by a relativistic configuration interaction method using the flexible atomic code(FAC) and AUTOSTRUCTURE code in this energy range. The calculated RR + DR rate coefficients show a good agreement with the measured value at the collision energy above 100 meV.However, large discrepancies have been found at low energy range especially below 10 meV, and the experimental results show a strong enhancement relative to the theoretical RR rate coefficients. For the electron–ion collision energy below 1 meV, it was found that the experimentally observed recombination rates are higher than the theoretically predicted and fitted rates by a factor of 1.5 to 3.9. The strong dependence of RR rate coefficient enhancement on the charge state of the ions has been found with the scaling rule of q^(3.0), reproducing the low-energy recombination enhancement effects found in other previous experiments.

Negative conversion of autoantibody profile in chronic hepatitis B:A case report

BACKGROUND Autoimmune antibodies are detected in many diseases.Viral infections are accompanied by several immunopathological manifestations.Some autoimmune antibodies have been associated with the immune response induced by virus or drugs.Thus,a comprehensive diagnosis of chronic hepatitis B combined with autoimmune hepatitis is required,and immunosuppressant or antiviral therapy should be carefully considered.CASE SUMMARY We present a case of a patient who had negative transformation of autoimmune antibodies during chronic active hepatitis B.A 50-year-old female who had a history of asymptomatic hepatitis B virus carriers for more than 10 years presented to the hospital with the complaint of weakness for 1 wk.Blood tests revealed elevated liver enzymes;the detection of autoantibodies was positive.Hepatitis B viral load was 72100000 IU/mL.The patient started tenofovir alafenamide fumigate 25 mg daily.Liver biopsy was performed,which was consistent with chronic active hepatitis B.The final diagnosis of the case was chronic active hepatitis B.The autoimmune antibodies turned negative after 4 wk of antiviral therapy.The patient recovered and was discharged with normal liver function.There was no appearance of autoantibodies,and liver function was normal at regular follow-ups.CONCLUSION Autoimmune antibodies may appear in patients with chronic active hepatitis.It is necessary to differentiate the diagnosis with autoimmune hepatitis.

Direct Coulomb explosion of N2O2+induced by monochromatic extreme ultraviolet photons at 38.5 eV

The direct Coulomb explosion of N2O2+has been investigated experimentally after double-ionization by a single extreme ultraviolet(EUV)photon with an energy of ~38.5 eV.From the ion–ion time-of-flight coincidence spectrum,the de-nitrogenation(N2O2+→N++NO+)and de-oxygenation(N2O2+→O++N+2)photodissociation channels of N2O2+are unequivocally identified.The measured kinetic energy release(KER)distribution of the de-nitrogenation channel presents a major peak accompanied by a shoulder structure.We find that the major peak can be attributed to the direct photodissociation of the 11△and 1^1Σ+states,while the shoulder structure should be ascribed to the predissociation of the1^1△and 1^1Σ+states via 13Πstate.

The Maximum Power Tracking Method and Reactive Compensation Simulation Research Based on DIgSILENT

This paper studies about the mechanical part of wind turbine and wind generator operation stability.1) It makes a comparative study of two control methods for maximum power tracking: curve fitting method and hill climbing algorithm, sets up improved control modules in DIgSLIENT and makes comparison research, thus gets the conclusion that the improved control modules of hill climbing algorithm has good effect on MPPT, and it is more desirable in the condition of steady wind. 2) This paper sets up SVC and STATCOM models and improved control modules in DIgSLIENT, which are connected to wind power system, verifying the validity of SVC and STATCOM models, and verifying its influence on wind power plant and system. The results of the study show that STATCOM is more helpful in voltage recovery when large disturbance of three-phase short-circuit happened in wind power grid, reactive compensation is more effective.

Simulation Study of Three Types of Distributed Power Based on EMTDC

In order to analyze the performances of directly-driven permanent magnet synchronous generator wind turbine (PMSG) connecting to the grid, photovoltaic array and microtubine, dynamic models of them are established. The validity of the established models and proposed control strategies are demonstrated by simulation system under the software package PSCAD/EMTDC.

Pharmacophore-based design,synthesis,and biological evaluation of novel 3-((3,4-dichlorophenyl)(4-substituted benzyl)amino)propanamides as cholesteryl ester transfer protein(CETP)inhibitors

Cholesteryl ester transfer protein （CETP） is a plasma glycoprotein that plays an important role in decreasing high-density lipoprotein cholesterol （HDL-C） levels and increasing low-density lipoprotein cholesterol （LDL-C） levels. Inhibition of CETP may be a new therapy for treating atherosclerosis. Herein, we report the development of a ligand-based pharmacophore model and pharmacophore-based virtual screening of the ZINC/big-n-greasy database, leading to the identification of compound H-10 as a potential CETP inhibitor in vitro. Based on H-10, a series of 3-（（3,4-dichlorophenyl）（4-substituted benzyl）amino） propanamides were designed, synthesized, and evaluated against CETP. Compound 41 was found to have the best activity, resulting in 85.0% inhibition of CETP at l0 μmol/L.

Low energy range dielectronic recombination of Fluorine-like Fe^17+at the CSRm

The accuracy of dielectronic recombination （DR） data for astrophysics related ions plays a key role in astrophysical plasma modeling. The absolute DR rate coefficient of Fe^17＋ ions was measured at the main cooler storage ring at the Institute of Modern Physics, Lanzhou, China. The experimental electron-ion collision energy range covers the first Rydberg series up to n = 24 for the DR resonances associated with the 2p1/2 →^2 p3/2△n= 0 core excitations. A theoretical calculation was performed by using FAC code and compared with the measured DR rate coefficient. Overall reasonable agreement was found between the experimental results and calculations. Moreover, the plasma rate coefficient was deduced from the experimental DR rate coefficient and compared with the available results from the literature. At the low energy range, significant discrepancies were found, and the measured resonances challenge state-of-the-art theory at low collision energies.

Synthesis of novel β-propanamides to inhibit cholesteryl ester transfer protein(CETP)

A novel series of β-propanamide derivatives as inhibitors of cholesteryl ester transfer protein（CETP）were synthesized.Previously,H3（IC_（50） 2 μmol/L） was observed to inhibit CETP moderately（Xie et ah,2016）.Structural modifications based on H3 led to discovery of the successful CETP inhibitor,known as 1-methyl-4-arylpyrazole.Using a similar approach,compound Q08 was identified as a highly potent CETP inhibitor with an IC_（50） of 490 nmol/L in vitro.

Hexagonal trumpet-like flowers growth induced by a colloidal crystal composite film

Hexagonal trumpet-like sodium hexafluorosilicate （SFS） flowers, grown on an ordered porous polystyrene film （OPPF）, were prepared via a synchronous dissolution/regrowth process. Their formation process can be divided into several steps： first, the dissolution of the silica spheres induced the crystallization of SFS onto the OPPF; second, some pores emerged on the closely packed bumps when being blown by the SiF4 gas; third, when the crystal was blown by continuous gas from the pores, the span of the top became larger than that of the bottom.