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Communications in Theoretical Physics 2020年第10期72卷 98-102页

作者： K Bakke h Belich Departamento de Física Universidade Federal da ParaíbaCaixa Postal 500858051-900João Pessoa-PBBrazil Departamento de Física e Química Universidade Federal do Espírito SantoAv.Fernando Ferrari514Goiabeiras29060-900VitoriaESBrazil

We investigate quantum effects on a nonrelativistic neutral particle with a permanent magnetic dipole moment that interacts with an electric *** neutral particle is also under the influence of a background that breaks the lorentz *** focus on the lorentz symmetry violation background determined by a space-like vector ***,we show that the effects of the violation of lorentz symmetry can yield an attractive Coulomb-type ***,we obtain the bound state solutions to the SchrÖdinger–Pauli equation and show that the spectrum of energy is a function of the Aharonov–Casher geometric quantum ***,we discuss the arising of persistent spin currents.

关键词： lorentz symmetry violation Aharonov–Casher effect persistent spin current Coulomb-type potential

Inhibition of sperm motility does not affect live-dead separation of bull sperm by glass beads

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Asian Journal of Andrology 2001年第3期3卷 193-198页

作者： Robert h.Foote Department of Animal Science Cornell University Ithaca NY 14853-4801 USA

Aim: This study was designed to explore factors which influence binding of dead versus live sperm to glass ***: Multiple semen collections from bulls were used to explore selective filtration of bull sperm as influencedby nonlethal inhibition of sperm motility with fluoride, killing of sperm by quick-freezing, alteration of the glass sur-face with silicone, and different intervals of sexual rest between semen collections. Results: A comparison of glassspheres 100, 200 and 390μm in diameter indicated that 200 μm spheres were optimal for selective filtration. Quantita-tive separation of live from dead sperm was demonstrated with a correlation between the percentage of motile sperm andretention of sperm by the filter of r = -0.87 (P l/l NaFl did not alter the proportion ofsperm retained by the filter despite inhibiting sperm motility during filtration, an inhibition which was reversible. Pro-portions of live-dead sperm, based upon eosin staining, were unaffected by fluoride. Coating the glass spheres with sil-icone greatly reduced selective filtration. Dead sperm adherence to glass was reduced and resistance to NaFl inhibitionwas increased by daily ejaculation versus one-week intervals of sexual rest. Conclusion; These studies indicate thatthe adherence of sperm to glass is primarily due to some form of physico-chemical change accompanying death of thesperm cell independent of active sperm motility. This attraction between the sperm plasma membrane and glass is modi-fied by the age of the ejaculated sperm. This information is useful in evaluating different clinical procedures used forsperm separation. (Asian J Androl 2001 Sep; 3: 193-198)

关键词： sperm motility glass spere filters silicone fluorides inhibition

Analysis of a Plasmonic Based Optical Fiber Optrode With Phase Interrogation

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Photonic Sensors 2016年第3期6卷 221-233页

作者： h. MOAYYED I. T. lEITE l. COElhO J. l. SANTOS D. VIEGAS CAP / INESC TEC - Technology and Science and Faculty of Sciences from the University of Porto Rua do CampoAlegre 687 4169-007 Porto Portugal INl - International Iberian Nanotechnology laboratory Av. Mestre Jose Veiga 4715-310 Braga Portugal

Optical fiber optrodes are attractive sensing devices due to their ability to perform point measurement in remote locations. Mostly, they are oriented to biochemical sensing, quite often supported by fluorescent and spectroscopic techniques, but with the refractometric approach considered as well when the objective is of high measurement performance, particularly when the focus is on enhancing the measurand resolution. In this work, we address this subject, proposing and analyzing the characteristics of a fiber optic optrode relying on plasmonic interaction. A linearly tapered optical fiber tip is covered by a double overlay： the inner one - a silver thin film and over it - a dielectric layer, with this combination allowing to achieve, at a specific wavelength range, surface plasmonic resonance （SPR） interaction sensitive Typically, the interrogation of the SPR sensing to the refractive index of the surrounding medium. structures is performed, considering spectroscopic techniques, but in principle, a far better performance can be obtained, considering the reading of the phase of the light at a specific wavelength located within the spectral plasmonic resonance. This is the approach which is studied here in the context of the proposed optical fiber optrode configuration. The analysis performed shows the combination of a silver inner layer with a dielectric titanium oxide layer with tuned thicknesses enables sensitive phase reading and allows the operation of the fiber optic optrode sensor in the third telecommunication wavelength window.

关键词： Optrode fiber sensing surface plasmon resonance phase interrogation metallic-oxide coupled layers

Src inhibition rescues FUNDC1-mediated neuronal mitophagy in ischaemic stroke

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Stroke & Vascular Neurology 2024年第4期9卷 367-379,I0022-I0031页

作者： Tianchi Tang li-bin hu Chao Ding Zhihua Zhang Ning Wang Tingting Wang hang Zhou Siqi Xia linfeng Fan Xiong-jie Fu Feng Yan Xiangnan Zhang Gao Chen Jianru li Department of Neurosurgery Zhejiang University School of Medicine Second Affiliated HospitalHangzhouZhejiangChina 2NeurosurgeryZhejiang University School of Medicine Second Affiliated HospitalHangzhouZhejiangChina 3Zhejiang University School of MedicineHangzhouZhejiangChina 4Zhejiang University Department of PharmacologyHangzhouZhejiangChina

Background Ischaemic stroke triggers neuronal mitophagy,while the involvement of mitophagy receptors in ischaemia/reperfusion(I/R)injury-induced neuronal mitophagy remain not fully ***,we aimed to investigate the involvement of mitophagy receptor FUN14 domain-containing 1(FUNDC1)and its modulation in neuronal mitophagy induced by I/R *** Wild-type and FUNDC1 knockout mice were generated to establish models of neuronal I/R injury,including transient middle cerebral artery occlusion(tMCAO)in vivo and oxygen glucose deprivation/reperfusion in *** outcomes of mice with two genotypes were *** mitophagy was analysed both in vivo and in *** of FUNDC1 and its regulator Src were *** impact of Src on FUNDC1-mediated mitophagy was assessed through administration of Src antagonist *** To our surprise,FUNDC1 knockout mice subjected to tMCAO showed stroke outcomes comparable to those of their wild-type *** neuronal mitophagy could be activated by I/R injury,FUNDC1 deletion did not disrupt neuronal *** activation of FUNDC1,represented by dephosphorylation of Tyr18,was detected in the early stages(within 3hours)of neuronal I/R injury;however,phosphorylated Tyr18 reappeared and even surpassed baseline levels in later stages(after 6hours),accompanied by a decrease in FUNDC1-light chain 3 *** inactivation of FUNDC1 was associated with Src activation,represented by phosphorylation of Tyr416,which changed in parallel with the level of phosphorylated FUNDC1(Tyr18)during neuronal I/R ***,FUNDC1-mediated mitophagy in neurons under I/R conditions can be rescued by pharmacological inhibition of *** FUNDC1 is inactivated by Src during the later stage(after 6hours)of neuronal I/R injury,and rescue of FUNDC1-mediated mitophagy may serve as a potential therapeutic strategy for treating ischaemic stroke.

关键词： FUNDC1 involvement injury

双歧杆菌和乳酸菌β-半乳糖苷酶转糖基作用的研究进展

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食品科学 2019年第7期40卷 335-341页

作者：姜陈波杭锋乳业生物技术国家重点实验室上海乳业生物工程技术研究中心光明乳业股份有限公司乳业研究院上海200436

双歧杆菌和乳酸菌作为一般认为安全的微生物,是β-半乳糖苷酶(β-galactosidase,β-gal)的较好来源。部分双歧杆菌和乳酸菌菌株能够产生具有转糖基活力的β-gal,以乳糖为底物可合成具有益生作用的低聚半乳糖(galactooligosaccharides,GO... 详细信息

双歧杆菌和乳酸菌作为一般认为安全的微生物,是β-半乳糖苷酶(β-galactosidase,β-gal)的较好来源。部分双歧杆菌和乳酸菌菌株能够产生具有转糖基活力的β-gal,以乳糖为底物可合成具有益生作用的低聚半乳糖(galactooligosaccharides,GOS),而GOS产物的产量和组成受到β-gal的来源以及反应条件的影响。因此,本文总结了能够产生具有转糖基活力的β-gal的双歧杆菌和乳酸菌菌株,比较了两类来源的β-gal的酶学性质,并重点阐述了这两类β-gal在GOS合成中的应用。

关键词： β-半乳糖苷酶乳酸菌双歧杆菌转糖基作用低聚半乳糖

An AI-empowered indoor digital contact tracing system for COVID-19 outbreaks in residential care homes

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Infectious Disease Modelling 2024年第2期9卷 474-482页

作者： Jiahui Meng Justina Yat Wa liu lin Yang Man Sing Wong hilda Tsang Boyu Yu Jincheng Yu Freddy Man-hin lam Daihai he lei Yang Yan li Gilman Kit-hang Siu Stefanos Tyrovolas Yao Jie Xie David Man David h.K.Shum School of Nursing The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Electronic and Information Engineering The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Research Centre of Textiles for Future Fashion The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Department of land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Department of Applied Mathematics The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina The Jockey Club School of Public health and Primary Care The Chinese University of Hong KongHong Kong Special Administrative RegionChina Department of Rehabilitation Sciences The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Department of Computing The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Department of health Technology and Informatics The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Department of Nutrition and Food Studies George Mason UniversityUSA Tung Wah College Hong Kong Special Administrative RegionChina Mental health Research Centre The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina

An AI-empowered indoor digital contact-tracing system was developed using a centralized architecture and advanced low-energy Bluetooth technologies for indoor positioning,with careful preservation of privacy and data *** analyzed the contact pattern data from two RChs and investigated a COVID-19 outbreak in one study *** evaluate the effectiveness of the system in containing outbreaks with minimal contacts under quarantine,a simulation study was conducted to compare the impact of different quarantine strategies on outbreak containment within *** significant difference in contact hours between weekdays and weekends was observed for some pairs of RCh residents and staff during the two-week data collection *** significant difference between secondary cases and uninfected contacts was observed in a COVID-19 outbreak in terms of their demographics and contact *** results based on the collected contact data indicated that a threshold of accumulative contact hours one or two days prior to diagnosis of the index case could dramatically increase the efficiency of outbreak containment within RChs by targeted isolation of the close *** study demonstrated the feasibility and efficiency of employing an AI-empowered system in indoor digital contact tracing of outbreaks in RChs in the post-pandemic era.

关键词： COVID-19 Indoor contact tracing Contact pattern Outbreak containment Artificial intelligence

A new model of speciation

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National Science Review 2019年第2期6卷 289-290页

作者： loren h.Rieseberg Department of Botany and Biodiversity Research Centre University of British Columbia NSR

In the first paragraph of ‘On the origin of species’, Darwin [1]refers to speciation as that ‘mystery of mysteries’. Although the means by which new species arise is no longer mysterious, some puzzles remain. One such puzzle, which is addressed in a recent paper from Chung-I Wu’s group on mangrove speciation [2],concerns the popular allopatric speciation model. In this model,

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Effects of hydroxyl Groups in Organic Ammonium Counterions on the Properties of Fluorinated Surfactants

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China Detergent & Cosmetics 2017年第4期2卷 57-65页

作者： Zhang Tiantian Zhou hongyu Wu Bowan Xiao Jinxin Xing hang longdong University-Fluobon Surfactant Engineering Technology Center College of Chemistry and Chemical EngineeringLongdong University Beijing FlUOBON Surfactant Institute

The surface tension, foaming and viscosity for C7F15COO^-N^＋h（C2h4Oh）χ（C2hs）3-x and C8F17SO3- N^＋h（C2h4Oh）χ（C2h5）3-χ （x = 0, 1, 2, 3） were measured to systematically study the effects of hydroxyl groups in organic ammonium counterions on the properties of perfluorooctanoates and perfluorooctanesulfonates. The results showed that the critical micelle concentration （cmc） and the surface tension at cmc （γcmc） were both increased with the increase of number of hydroxyl groups （χ） in the two series. The perfluorooctanesulfonate had smaller cmc but higher γ=cmc than perfluorooctanoate with the same counterion. The minimum molecular area of surface adsorption （Amin） of C8F17zSO3^-N^＋h（C2h4Oh）χ（C2h5）3-χ were 0.64, 0.57, 0.63 and 0.72 nm^2 while the Amin values of C7F15COO^-N^＋h（C2h4Oh）χ（C2h5）3-χ were 0.61, 0.62, 0.61 and 0.71 nm^2 when χ = 0, 1, 2 and 3, respectively. For the investigated systems of surfactants, the results of foam expansion ratio agreed with those of surface activity, while the 25% drainage time were consistent with the results of viscosity.

关键词： counter-ion organic ammonium ion fluorocarbon surfactant foam surface activity micellization

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忆魏廷格先生

人民音乐 2022年第3期 66-68页

作者：李航《钢琴音乐》

时间走得太快,魏廷格老师离开我们已经三个月了,还是经常会想起与他见面最经典的一句开场白:我,魏某人……一边说一边微微摇着头摆着手。回想起和魏老师的相识是在1 997年底,那时的我初进《钢琴艺术》杂志,他作为杂志创办人之一,担任副... 详细信息

时间走得太快,魏廷格老师离开我们已经三个月了,还是经常会想起与他见面最经典的一句开场白:我,魏某人……一边说一边微微摇着头摆着手。回想起和魏老师的相识是在1 997年底,那时的我初进《钢琴艺术》杂志,他作为杂志创办人之一,担任副主编一职。对于这样的大人物,作为晚辈只有仰望的份儿。

关键词：创办人开场白老师大人物《钢琴艺术》副主编杂志

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Efects of Molybdenum Concentration and Valence State on the Structural and Magnetic Properties of BaFe_(11.6)Mo_xZn_(0.4-x)O_(19) hexaferrites

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Acta Metallurgica Sinica(English letters) 2013年第5期26卷 509-516页

作者： G.h.Dushaq S.h.Mahmood I.Bsoul h.K.Juwhari B.lahlouh M.A.AlDamen Physics Department The University of Jordan Physics Department Al al-Bayt University Chemistry Department The University of Jordan

Barium hexaferrites BaFe11.6Mox Zn0.4-x O19（x=0.1,0.2,0.4）were prepared by precipitation of the precursors using wet chemical mixture method and then sintering the dried powders at 1100℃.The properties of the prepared samples were investigated using X-ray difraction（XRD）,scanning electron microscopy（SEM）,vibrating sample magnetometer,and Mssbauer *** patterns revealed that all prepared samples had BaFe12O19hexaferrite structure as a majority *** images demonstated that the samples consisted mainly of hexagonal platelet-like grains with diameters ranging from 100 to 500 nm.Mssbauer spectra revealed that Zn2＋ions occupy 4f1 sites leading to the splitting of the 12k *** Mo6＋ions occupy 2b sites while Mo4＋ prefer 4f1 and 12k *** the sample with x=0.4,Mo6＋and Mo4＋ ions were found to have preference for 2b and 12k sites,respectively,and to induce the development of Fe2＋ions in the hexaferrite,leading to noticeable changes in the magnetic properties of the *** observed magnetic properties were found to be consistent with the preferential site occupation of metal ions,and the hyperfine fields derived from Mssbauer spectra of these samples.

关键词： Coercivity Barium hexaferrites Mossbauer spectroscopy Magneticproperties hyperfine Interactions