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Angularity in Higgs boson decays via H→gg at NNLL' accuracy

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Chinese Physics C 2025年第02期 64-84页

作者：朱佳伟宋昱锦高俊 Daekyoung Kang Tanmay Maji key laboratory of Nuclear Physics and ion-beam Application (MOE) and Institute of Modern Physics Fudan University School of Physics and Astronomy Shanghai Key Laboratory for Particle Physics and Cosmologyand Key Laboratory for Particle Astrophysics and Cosmology (MOE)Shanghai Jiao Tong University Department of Physics Korea University Department of Physics National Institute of Technology

We present improved predictions of a class of event-shape distributions called angularity for a contribution from an effective operator H→gg in Higgs hadronic decay that suffers from large perturbative uncertainties. In the framework of the soft-collinear effective theory, logarithmic terms of the distribution are resummed at NNLL' accuracy, for which a two-loop constant of gluon-jet function for angularity is independently determined using a fit to the fixed-order distribution at the NLO corresponding to O（αs2） relative to the Born rate. Our determination has reasonable agreement with the value in a recently released thesis. In the fit, we use an asymptotic form with a fractional power conjectured from recoil corrections at one-loop order, and it improves the accuracy of determining positive values of the angularity parameter a. The resummed distribution is matched to the NLO fixed-order results to make our predictions valid at all angularity values. We also discuss the first and subtracted moments of angularity as a function of a that enable the extraction of information on leading and subleading nonperturbative corrections associated with gluons.

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Optimization of L-lactic Acid Production of Rhizopus Oryzae Mutant RLC41-6 by ion beam Implantation at Low-Energy

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Plasma Science and Technology 2005年第5期7卷 3078-3080页

作者：周秀红葛春梅姚建铭潘仁瑞余增亮 key laboratory of ion beam bioengineering Chinese Academy of Sciences

In order to obtain an industrial strain with a higher L（＋）-lactic acid yield, the strain Rhizopus oryzae RF3608 was mutated by means of nitrogen ion beam implantation and the mutant strain RLC41-6 was isolated. Under optimal conditions the yield of L（＋）-lactic acid produced in a shake-flask reached 133 g/L - 137 g/L after 36 h cultivation, indicating that the conversion rate based on glucose was as high as 88% - 91% and the productivity was 3.75 g/L.h. It was almost a 115% increase in lactic acid production compared with the original strain RF3608.

关键词： ion implantation fermentation L(+)-lactic acid Rhizopus oryzae

Effects of 13 T Static Magnetic Fields (SMF) in the Cell Cycle Distribution and Cell Viability in Immortalized Hamster Cells and Human Primary Fibroblasts Cells

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Plasma Science and Technology 2010年第1期12卷 123-128页

作者：赵国平陈少鹏赵烨朱玲燕黄佩鲍凌志王军王磊吴李君吴跃进许安 key laboratory of ion beam bioengineering Institute of Plasma PhysicsChinese Academy of Sciences

Magnetic resonance image （MRI） systems with a much higher magnetic flux density were developed and applied for potential use in medical diagnostic. Recently, much attention has been paid to the biological effects of static, strong magnetic fields （SMF）. With the 13 T SMF facility in the Institute of Plasma Physics, Chinese Academy of Sciences, the present study focused on the cellular effects of the SMF with 13 T on the cell viability and the cell cycle distribution in immortalized hamster cells, such as human-hamster hybrid （AL） cells, Chinese hamster ovary （CHO） cells, DNA double-strand break repair deficient mutant （XRS-5） cells, and human primary skin fibroblasts （AG1522） cells. It was found that the exposure of 13 T SMF had less effect on the colony formation in either nonsynchronized or synchronized AL cells. Moreover, as compared to non-exposed groups, there were slight differences in the cell cycle distribution no matter in either synchronized or nonsynchronized immortalized hamster ceils after exposure to 13 T SMF. However, it should be noted that the percentage of exposed AG1522 cells at G0/G1 phase was decreased by 10% as compared to the controls. Our data indicated that although 13 T SMF had minimal effects in immortalized hamster cells, the cell cycle distribution was slightly modified by SMF in human primary fibroblasts.

关键词： static magnetic fields immortalized hamster cells human primary fibroblasts cells

The Mutation Breeding and Mutagenic Effect of Air Plasma on Penicillium Chrysogenum

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Plasma Science and Technology 2012年第4期14卷 297-302页

作者：桂芳王辉王鹏刘会蔡晓春胡以华袁成凌郑之明 key laboratory of ion beam bioengineering Chinese Academy of Sciences Electronic Engineering Institute

Low temperature air plasma was used as the mutation tool for penicillin-producing strain Penicillium chrysogenum. The discharge conditions were RF power of 360 W, temperature of 40℃ in a sealed chamber, and pressure of 10 Pa to 30 Pa. The result showed that the kinetics of the survival rate followed a typical saddle-shaped curve. Based on a statistic analysis, at the treating duration of 10 min, the positive mutation rate was as high as 37.5% while the negative mutation rate was low. The colonial morphology changed obviously when the plasma treating duration reached or exceeded 45 min. After both primary and secondary screening, a mutant designated as aPc051310 with high productivity of penicillin was obtained, and a strong mutagenic effect on P. chrysogenurn was observed in the process. It was proved that after five generations, the mutant aPc051310 still exhibits a high productivity. All the results prove that the plasma mutation method could be developed as a convenient and effective tool to breed high-yield strains in the fermentation industry, while expanding the plasm application at the same time.

关键词： low temperature air plasma Penicillium chrysogenum mutation breeding mutation mechanism

A Mutant of Bacillus Subtilis with High-Producing Surfactin by ion beam Implantation

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Plasma Science and Technology 2006年第4期8卷 491-496页

作者：刘清梅袁航王军贡国鸿周伟樊永红王丽姚建铭余增亮 key laboratory of ion beam bioengineering Chinese Academy of SciencesHefei 230031China

In order to generate a mutant of Bacillus subtilis with enhanced surface activity through low energy nitrogen ion beam implantation, the effects of energy and dose of ions implanted were studied. The morphological changes in the bacteria were observed by scanning electron microscope （SEM）. The optimum condition of ions implantation, 20 keV of energy and 2.6 × 10^15N^＋/cm^2 in dose, was determined. A mutant, B.s-E-8 was obtained, whose surface activity of 50-fold and 100-fold diluted cell-free Landy medium was as 5.6-fold and 17.4-fold as the wild strain. The microbial growth and biosurfactant production of both the mutant and the wild strain were compared. After purified by ultrafiltration and SOURCE 15PHE, the biosurfactant was determined to be a complex of surfactin family through analysis of electrospray ionization mass spectrum （ESI/MS） and there was an interesting finding that after the ion beam implantation the intensities of the components were different from the wild type strain.

关键词： bacillus subtilis surfactin low energy ion beam implantation mutation breeding

Enhancement of Gongronella *** Chitosanase Production by ion beam Implantation

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Plasma Science and Technology 2007年第1期9卷 115-118页

作者：袁航周伟王军张束清姚建铭 key laboratory of ion beam bioengineering Chinese Academy of SciencesHefei 230031China

Gongronella sp. JG was a fungal strain which expressed extracellular chitosanase of about 800 U/L during its growth in production medium. To improve its enzyme production, low energy N＋ implantation was employed to mutate spores of JG. The implantation condition was optimized and the parameters of 15 keV and 60 × breeding experiments. A mutant designated as SG 2.6 × 10^13 ions/cm^2 were selected for further was obtained. It showed increased chitosanase production （1800 U/L） and shortened cultivation period （from 72 h to 60 h）. Five-generation cultivation of SG indicated that its chitosanase production was stable at about 1800 U/L.

关键词： breeding chitosanase Gongronella sp. ion beam implantation

Analysis and Optimization of Stability of CAS-LIBB Single ion Microbeam

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Plasma Science and Technology 2008年第5期10卷 651-654页

作者：许明亮许永建詹福如陈斌陈连运李军余增亮 key laboratory of ion beam bioengineering Chinese Academy of SciencesHefei 230031China

Single ion microbeam is the most advanced technology which can emit a single ion for precise localization. A single-ion microbeam facility has been constructed at the key laboratory of ion beam bioengineering （LIBB）, Chinese Academy of Sciences （CAS）, with a spatial resolutions of about 5 μm. Based on CAS-LIBB microbeam, three key elements affecting the quality of the system are assessed： the size of beam spot, the energy range and the counting accuracy of implanting ions. Various contributions to the ion beam stability, including the ion source, the terminal voltage of electrostatic accelerator and the components in beam pipeline, are discussed. Analysis shows that the improvement of terminal voltage stability is the most important issue for future optimization of CAS-LIBB facility. Some preliminary investigations and project aimed at optimization and development are proposed as well.

关键词： single ion microbeam electrostatic accelerator ion beam stability

Caffeine Markedly Enhanced Radiation-Induced Bystander Effects

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Plasma Science and Technology 2009年第2期11卷 250-254页

作者：蒋而康吴李君 key laboratory of ion beam bioengineering Institute of Plasma PhysicsChinese Academy of Sciences

In this paper it is shown that incubation with 2 mM caffeine enhanced significantly the MN （micronucleus） formation in both the 1 cGy α-particle irradiated and non-irradiated by- stander regions. Moreover, caffeine treatment made the non-irradiated bystander cells more sensitive to damage signals. Treated by c-PTIO（2-（4-carboxy-phenyl）-4,4,5,5-tetramethyl-imidazoline- 1-oxyl-3-oxide）, a nitric oxide （NO） scavenger, the MN frequencies were effectively inhibited, showing that nitric oxide might be very important in mediating the enhanced damage. These results indicated that caffeine enhanced the low dose m-particle radiation-induced damage in irradiated and non-irradiated bystander regions, and therefore it is important to investigate the relationship between the radiosensitizer and radiation-induced bystander effects （RIBE）.

关键词： caffeine co-culture RIBE

Optimization of L(+)-Lactic Acid Production from Xylose with Rhizopus Oryzae Mutant RLC41-6 Breeding by Low-Energy ion Implantation

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Plasma Science and Technology 2007年第5期9卷 638-642页

作者：杨英歌樊永红李文王冬梅吴跃进郑之明余增亮 key laboratory of ion beam bioengineering Chinese Academy of SciencesHefei 230031China Bioengineering high vocational school of XuzhouXuzhou 221006China key laboratory of ion beam bioengineering Chinese Academy of SciencesHefei 230031China

In order to obtain an industrial strain with a higher L（＋）-lactic acid yield, the strain Rhizopus oryzae PW352 was mutated by means of nitrogen ion beam implantation and the mutant strain Rhizopus oryzae RLC41-6 was obtained. An experimental finding was made in surprise that Rhizopus oryzae mutant RLC41-6 is not only an L（＋）-lactic acid producer from corn starch but also an efficient producer of L（＋）-lactic acid from xylose. Under optimal conditions, the production of L（＋）-lactic acid from 100 g/L xylose reached 77.39 g/L after 144 h fed-batch fermentation, A high mutation rate and a wide mutation spectrum of low-energy ion implantation were observed in the experiment.

关键词： L(+)-lactic acid xylose Rhizopus oryzae ion implantation