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Plasma effects on the bacteria Escherichia coli via two evaluation methods

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Plasma Science and Technology 2017年第7期19卷 102-109页

作者： Danijela VUJO?EVI? Uro? CVELBAR Ur?ka REPNIK martina MODIC sa?a LAZOVI? Tina ZAVA?NIK-BERGANT Nevena PUA? Boban MUGO?A Evangelos GOGOLIDES Zoran Lj PETROVI? Miran MOZETI? Institute of Public Health Jozef Stefan Institute Institute of Physics University of Belgrade Institute of nanoscience and nanotechnology (INN) National Center for Scientific Research NCSR Demokritos

The degradation of Escherichia coli bacteria by treatment with cold, weakly ionised, highly dissociated oxygen plasma, with an electron temperature of 3 eV, a plasma density of 8 × 10^15 m^-3 and a neutral oxygen atom density of 3.5 × 10^21 m^-3 was studied. To determine the ＇real＇ plasma effects, two methods were used for evaluation and determination, as well as a comparison of the number of bacteria that had survived： the standard plate count technique （PCT） and advanced fluorescence-activated cell sorting （FACS）. Bacteria were deposited onto glass substrates and kept below 50 ℃ during the experiments with oxygen plasma. The results showed that the bacteria had fully degraded after about 2 min of plasma treatment, depending slightly on the amount of bacteria that had been deposited on the substrates. The very precise determination of the O flux on the substrates and the two-method comparison allowed for the determination of the critical dose of oxygen atoms required for the destruction of a bacterial cell wall--about 6 × 10^24 m^-2--as well as deactivation of the substrates--about 8 × 10^25 m^-2. These results were taken in order to discuss other results obtained by comparable studies and scientific method evaluations in the determination of plasma effects on bacteria.

关键词： oxygen plasma bacteria degradation PCT FACS

naturally occurring spike mutations influence the infectivity and immunogenicity of saRS-CoV-2

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Cellular & Molecular Immunology 2022年第11期19卷 1302-1310页

作者： Qiaoli Peng Runhong Zhou na Liu Hui Wang Haoran Xu Meiqing Zhao Dawei Yang ka-Kit Au Haode Huang Li Liu Zhiwei Chen AIDS Institute Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionPR China national Clinical Research Center for Infectious Diseases HKU AIDS Institute Shenzhen Research LaboratoryThe Third People’s Hospital of Shenzhen and The Second Affiliated Hospital of Southern University of Science and TechnologyShenzhenGuangdongPR China Department of Microbiology Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionPR China Centre for Virology Vaccinology and Therapeutics LimitedThe University of Hong KongHong Kong Special Administrative RegionPR China HKU AIDS Institute Joint Laboratory Department of Clinical Microbiology and Infection ControlThe University of Hong Kong-Shenzhen HospitalShenzhenGuangdongPR China State Key Laboratory of Emerging Infectious Disease The University of Hong KongHong Kong Special Administrative RegionPR China

Mutations in saRS-CoV-2 variants of concern(VOCs)have enhanced transmissibility and immune evasion with respect to current vaccines and neutralizing antibodies(nabs).How naturally occurring spike mutations affect the infectivity and antigenicity of VOCs remains to be *** entry efficiency of individual spike mutations was determined in vitro using pseudotyped ***/c mice were immunized with 2-dose Dna vaccines encoding B.1.1.7,B.1.351,B.1.1.529 and their single *** and humoral immune responses were then compared to determine the impact of individual mutations on *** the B.1.1.7 lineage,Del69–70 and Del 144 in NTD,A570D and P681H in SD1 and S982A and D1118H in S2 significantly increased viral entry,whereas T716I resulted in a *** the B.1.351 lineage,L18F and Del 242–244 in the NTD,K417N in the RBD and A701V in S2 also increased viral entry.S982A weakened the generation of binding *** sera showed reduced cross-neutralization activity against B.1.351,B.1.617.2(Delta)and B.1.1.529(Omicron BA.1).S982A,L18F,and Del 242–244 hindered the induction of cross-nabs,whereas Del 69–70,Del144,R246I,and K417N showed the opposite effects.B.1.351 elicited adequate broad cross-nabs against both B.1.351 and *** immunogens tested,however,showed low neutralization against circulating *** addition,T-cell responses were unlikely affected by mutations tested in the *** conclude that individual spike mutations influence viral infectivity and vaccine *** VOC-targeted vaccines is likely necessary to overcome immune evasion from current vaccines and neutralizing antibodies.

关键词： saRS-CoV-2 Variants of Concern Single mutation neutralizing antibody T cell responses vaccine immunogenicity

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利用择形分子筛异构化亚甲基二苯胺

Chinese Journal of Catalysis 2024年第7期62卷 124-130页

作者： sam Van Minnebruggen ka Yan Cheung Trees De Baerdemaeker Niels Van Velthoven matthias Degelin Galahad O’Rourke Hiroto Toyoda Andree Iemhoff Imke Muller Andrei-Nicolae Parvulescu Torsten mattke Jens Ferbitz 吴勤明肖丰收 Toshiyuki Yokoi Nils Bottke Dirk De Vos 巴斯夫股份有限公司膜分离、吸附、催化和光谱学可持续解决方案中心(cmaCS) 比利时巴斯夫股份有限公司研究组德国东京工业大学纳米空间催化研究所横滨日本浙江大学化学系浙江杭州310028

亚甲基二苯胺(MDA)被广泛用作生产聚氨酯和聚异氰脲酸酯的中间体.然而,当前MDA的生产工艺在控制(4,4’/(2,4’+2,2’))异构体比例方面还存在局限.其中,4,4’-MDA被认为是最有价值的异构体.尽管2,4'-MDA在市场上也有一定的需求,但如果能... 详细信息

亚甲基二苯胺(MDA)被广泛用作生产聚氨酯和聚异氰脲酸酯的中间体.然而,当前MDA的生产工艺在控制(4,4’/(2,4’+2,2’))异构体比例方面还存在局限.其中,4,4’-MDA被认为是最有价值的异构体.尽管2,4'-MDA在市场上也有一定的需求,但如果能将其有效地转化为4,4'-MDA,将能显著提升其附加值.本文在使用苯胺的条件下,利用β分子筛等催化剂,通过双分子机制,可以选择性地将2,4'-MDA异构化为4,4'-MDA.尽管实验显示,多种酸性沸石具有较高的异构化活性,但MCM-68(具有MSE拓扑结构)的催化性能尤为出色,它不仅展现出高异构化活性,而且具有很好的选择性.MCM-68主要催化2,4'-MDA异构化为4,4'-MDA,而2,2'-MDA和低聚物的形成则可以忽略不计.本文还深入探讨了该择形作用的原因,并详细研究了酸位置在MSE分子筛孔道限制中的关键作用.

关键词：铝分布多相催化异构化亚甲基二苯胺聚氨酯择形

Late Diagnosis of Congenital Optic Disc Abnormalities

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Open Journal of Ophthalmology 2024年第3期14卷 229-235页

作者： Aïssatou Aw Soda Mbaye Jean Pierre Diagne Sy El Hadji malick Alassane Ba Aly Mbara ka Serigne Sohibou Gaye Ousmane Ndiaga Senghor Lamine Ndiaye Mouhamed Ndiaye El Hadj Abdellahi Seyid Papa Amadou Ndiaye Ophthalmology Department of Abass NDAO Hospital Cheikh Anta Diop University Dakar Senegal

Purpose: To show epidemiological and imaging aspects of congenital optic disc abnormalities diagnosed late. Method: It was a retrospective study, including all patients with congenital optic disc abnormalities diagnosed at a late age between January 2020 and October 2022 at the eye center of Abass Ndao Hospital. Complete ophthalmological examination was performed with eye imaging according to the cases. Results: 09 patients (10 eyes) were diagnosed with congenital optic disc abnormalities. The mean age was 29 years, with a sex ratio of 0.8. Three patients had consulted for unilateral decreased visual acuity since childhood, two for sudden vision loss and in four cases the diagnosis was fortuitous. Visual acuity was ranged from 1/200 to 20/20. Fundus examination showed myelinated retinal nerve fibers in four eyes, optic disc pit in three eyes including two complicated by maculopathy, two cases of morning glory syndrome and a case of pseudoduplication of the optic disc. Optical coherence tomography, ocular ultrasound B and OCT-Angiography were performed according to the cases. Conclusion: Congenital optic disc abnormalities are often diagnosed late. They are potentially amblyogenic and complications are not rare, worsening the visual prognosis. Their screening should be systematic by ophthalmological examination in newborns.

关键词： Myelinated Nerves Fibers Optic Disc Pit Morning Glory Syndrome Pseudoduplication Optic Disc

All-parameters Rayleigh wave inversion

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Earthquake Engineering and Engineering Vibration 2021年第2期20卷 517-534页

作者： Xiao-Hui Yang ka-Veng Yuen State Key Laboratory of Internet of Things for Smart City and Department of Civil and Environmental Engineering University of MacaoMacao 999078China

Since S-wave velocity of the subsurface is an important parameter in near surface applications,many studies have been conducted for its *** the various methods that use surface waves or body waves,Rayleigh wave inversion is the most *** practice,the densities and P-wave velocities of different layers are usually assumed to be known to avoid ill-posed problems,as they have less influence on the dispersion ***,improper assignment of these two groups of parameters leads to inaccurate estimation of the S-wave velocity *** order to address this problem,the all-parameters Rayleigh wave inversion strategy is proposed in which the S-wave velocities,layer thicknesses,densities and P-wave velocities of different layers are included as the unknown parameters for ***,the transitional markov Chain Monte Carlo(TMCMC)algorithm is applied for the implementation of all-parameters Rayleigh wave *** simulated example and two real-test applications are demonstrated to verify the capability of the proposed method in the estimation of the S-wave velocity profile,the densities and the P-wave ***,it is verified that the proposed method achieved more accurate S-wave velocity profile estimation than the traditional approach.

关键词： all-parameters Rayleigh wave inversion Bayesian S-wave velocity profile TMCMC algorithm uncertainty quantification

Bayesian Rayleigh wave inversion with an unknown number of layers

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Earthquake Engineering and Engineering Vibration 2020年第4期19卷 875-886页

作者： ka-Veng Yuen Xiao-Hui Yang State Key Laboratory of Internet of Things for Smart City and Department of Civil and Environmental Engineering University of Macao999078MacaoChina

Surface wave methods have received much attention due to their efficient, flexible and convenient characteristics. However, there are still critical issues regarding a key step in surface wave inversion. In most existing methods, the number of layers is assumed to be known prior to the process of inversion. However, improper assignment of this parameter leads to erroneous inversion results. A Bayesian nonparametric method for Rayleigh wave inversion is proposed herein to address this problem. In this method, each model class represents a particular number of layers with unknown S-wave velocity and thickness of each layer. As a result, determination of the number of layers is equivalent to selection of the most applicable model class. Regarding each model class, the optimization search of S-wave velocity and thickness of each layer is implemented by using a genetic algorithm. Then, each model class is assessed in view of its efficiency under the Bayesian framework and the most efficient class is selected. Simulated and actual examples verify that the proposed Bayesian nonparametric approach is reliable and efficient for Rayleigh wave inversion, especially for its capability to determine the number of layers.

关键词： Bayesian model class selection generalized r/t coefficients algorithm genetic algorithm inversion of Rayleigh wave number of layers

The Most General Corrdinate Transformation Between the Hydrogen Atom and Harmonic Oscillator in Arbitrary Dimensions

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Chinese Physics Letters 1997年第10期14卷 721-723页

作者： SU ka-lin Department of Physics Yueyang Normal CollegeYueyang 414000

In this paper,we find out the most general coordinate transformation between a d-dimensional hydrogen atom and a D-dimensional harmonic oscillator by means of the SU(1,l)*** other words,the generalized Kustaanheimo-St... 详细信息

关键词： algebra Transformation coordinate

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三轴加载下灰岩的力学特性及声发射特征

矿业研究与开发 2024年第2期44卷 129-137页

作者：王巍浩杜西岗许城高凯河北水利电力学院交通工程系河北沧州市061001 中冶(上海)钢结构科技有限公司上海201908 中绎建设科技集团有限公司河北石家庄050035

灰岩作为煤矿广泛赋存的沉积岩之一,揭示其力学性质和损伤演化过程对于煤炭资源的安全开采至关重要。针对取自淮北某矿81采区-950 m回风石门底板的灰岩试样进行了不同围压下的三轴压缩试验,并采用声发射对灰岩的变形破坏全过程进行监测... 详细信息

灰岩作为煤矿广泛赋存的沉积岩之一,揭示其力学性质和损伤演化过程对于煤炭资源的安全开采至关重要。针对取自淮北某矿81采区-950 m回风石门底板的灰岩试样进行了不同围压下的三轴压缩试验,并采用声发射对灰岩的变形破坏全过程进行监测。试验结果表明:(1)灰岩的应力-应变曲线可划分为四个阶段。随着围压的增大,弹性模量E、泊松比μ、起裂应力σ_(ci)以及峰值应力σ_(pv)均会增大,但闭合应力σ_(c)基本保持不变;应力比σ_(c)/σ_(pv)随围压的增大而减小,σ_(ci)/σ_(pv)与σ_(r)/σ_(pv)对围压变化不敏感,残余应力σ_(r)处的内聚力和内摩擦角相比于峰值应力处分别降低了18.94%和26.27%。(2)声发射(AE)演化能够较好地表征灰岩的渐进性破坏过程,不同围压下灰岩的声发射演化规律保持一致;振铃计数峰值随着围压的增大而减小,声发射幅值均分布在20~100 dB范围内,灰岩试样内的高幅值AE事件会随着轴向应力的加载增多并呈聚集分布。(3)以累计振铃计数作为特征参量建立的损伤演化模型能够较好地描述三轴应力下灰岩内部的微裂隙闭合、扩展、贯通直至发生宏观破坏这一渐进性破坏过程。

关键词：灰岩三轴压缩力学性质声发射损伤演化

Combining acellular nerve allografts with brainderived neurotrophic factor transfected bone marrow mesenchymal stem cells restores sciatic nerve injury better than either intervention alone

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Neural Regeneration Research 2014年第20期9卷 1814-1819页

作者： Yanru Zhang Hui Zhang Gechen Zhang ka ka Wenhua Huang School of International Education Zhengzhou University Institute of Clinical Anatomy Southern Medical University Department of Orthopedic Surgery First Affiliated Hospital of Zhengzhou University

In this study, we chemically extracted acellular nerve allografts from bilateral sciatic nerves, and repaired 10-mm sciatic nerve defects in rats using these grafts and brain-derived neurotrophic factor transfected bone marrow mesenchymal stem cells. Experiments were performed in three groups： the acellular nerve allograft bridging group, acellular nerve allograft ＋ bone marrow mesenchymal stem cells group, and the acellular nerve allograft ＋ brain-derived neurotrophic factor transfected bone marrow mesenchyrnal stem cells group. Results showed that at 8 weeks after bridging, sciatic functional index, triceps wet weight recovery rate, myelin thickness, and number of myelinated nerve fibers were significantly changed in the three groups. Variations were the largest in the acellular nerve allograft ＋ brain-derived neurotrophic factor transfected bone marrow mesenchymal stem cells group compared with the other two groups. Experimental findings suggest that chemically extracted acellular nerve allograft combined nerve factor and mesenchymal stem cells can promote the restoration of sciatic nerve defects. The repair effect seen is better than the single application of acellular nerve allograft or acellular nerve allograft combined mesenchymal stem cell transplantation.

关键词： nerve regeneration peripheral nerve regeneration peripheral nerve injury chemicallyextracted acellular nerve brain-derived neurotrophic factor bone marrow mesenchymal stem cells nerve tissue engineering neural regeneration