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Chinese Physics B 2023年第6期32卷 259-269页

作者： H Ahmad B Nizamani m Z Samion N Yusoff m F Ismail Photonics Research Centre Universiti Malaya50603 Kuala LumpurMalaysia Physics Department Faculty of ScienceUniversiti Malaya50603 Kuala LumpurMalaysia Distinguished Visiting Professor Universiti Kuala Lumpur British Malaysian Institute(UniKL BMI)Batu 8Jln Sungai Pusu53100SelangorMalaysia

We demonstrate antimonene as a saturable absorber(SA) to generate an ultrafast mode-locked and Q-switched laser in the 2 μm wavelength region. The two antimonene-based SAs were prepared and inserted separately in a thulium–holmiumdoped fiber laser to produce the pulsed laser. Antimonene was coated onto a tapered fiber to generate soliton mode-locked pulses and used in thin-film form for the generation of Q-switched pulses. The mode-locking was stable within a pump power of 267 m W–511 m W, and the laser operated at a central wavelength of 1897.4 nm. The mode-locked laser had a pulse width of 1.3 ps and a repetition rate of 12.6 mHz, with a signal-to-noise ratio of 64 d B. Q-switched laser operation was stable at a wavelength of 1890.1 nm within a pump power of 312 m W–381 m W. With the increase in pump power from 312 m W to 381 m W, the repetition rate increased to a maximum of 56.63 k Hz and the pulse width decreased to a minimum value of 2.85 μs. Wide-range tunability of the Q-switched laser was also realized within the wavelength range of1882 nm–1936 nm.

关键词： mode-locking Q-switched fiber laser optical saturable absorber

One-loop approximation of mφller scattering in generalized Krein-space quantization

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Science China(Physics,mechanics & Astronomy) 2009年第2期52卷 212-217页

作者： F. PAYANDEH m. mEHRAFARIN m. V. TAKOOK Physics Department Amirkabir University of Technology Payame Noor University Physics Department Razi University

It has been shown that the negative-norm states necessarily appear in a covariant quantization of the free minimally coupled scalar field in de Sitter spacetime. In this processes ultraviolet and infrared di- vergences have been automatically eliminated. A natural renormalization of the one-loop interacting quantum field in minkowski spacetime (λφ 4) has been achieved through the consideration of the nega- tive-norm states defined in Krein space. It has been shown that the combination of quantum field theory in Krein space together with consideration of quantum metric fluctuation, results in quantum field the- ory without any divergences. Pursuing this approach, we express Wick’s theorem and calculate mφller scattering in the one-loop approximation in generalized Krein space. The mathematical consequence of this method is the disappearance of the ultraviolet divergence in the one-loop approximation.

关键词： quantum field theory Krein space negative energy states

2D CFD Analysis and Experimental Analysis on the Effect of Hub to Tip Ratios on the Performance of 0.6 m Impulse Turbine

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Journal of Thermal Science 2004年第4期13卷 315-320页

作者： A. THAKKER m.El. HEmRY Wave Energy Research Team Department of mechanical and Aeronautical Engineering University of Limerick IrelandWave Energy Research Team Department of Mechanical and Aeronautical Engineering University of Limerick Ireland

The objective of this paper is to present the performance comparison of 2D Computational Fluid Dynamics (CFD) analysis with experimental analysis of 0.6 m impulse turbine with fixed guide vanes for both 0.6 and 0.7 hub to tip ratio (H/T). Also the comparison of 2D CFD analysis of the said turbine with different values of H/T ranging from 0.5 to 0.7. A 2D-cascade model was used for CFD analysis while uni-directional steady flow was used for experimental analysis. The blade and guide vane geometries are based on 0.6 m rotor diameter, with optimum profile, and different H/T of 0.5, 0.6 and 0.7. It was concluded from 2D CFD analysis that 0.5 H/T ratio performances was higher than that of 0.6 and 0.7 H/T at peak efficiency and the operational flow range for 0.5 H/T was found to be wider than that of 0.6 and 0.7 H/T ratio.

关键词： wave energy impulse turbine computational fluid dynamics (CFD).

measurement of the pion form factor for m_(ππ)～2 between 0.1 and 0.85 GeV^2 with the KLOE detector

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Chinese Physics C 2010年第6期34卷 686-691页

作者： Stefan E.müller Institut für Kernphysik Johannes Gutenberg-Universitt

The KLOE experiment at the φ-factory DAФPNE has measured the pion form factor in the range between 0.1 〈 mππ^2 〈 0.85 GeV^2 using events taken at √s = 1 GeV with a photon emitted at large polar angles in the initial state. This measurement extends the mππ^2 region covered by KLOE ISR measurements of the pion form factor down to the two pion production threshold. The value obtained in this measurement of the dipion contribution to the muon anomalous magnetic moment of △αμ^ππ= （478.5±2-0stat±4.8syst±2.9theo）·10^-10 further confirms the discrepancy between the Standard model evaluation for αμ and the experimental value measured by the （g-2） collaboration at BNL.

关键词： hadronic cross section initial state radiation pion form factor muon anomaly

m2BPGi for assessing liver fibrosis in patients with hepatitis C treated with direct-acting antivirals

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World Journal of Gastroenterology 2020年第21期26卷 2864-2876页

作者： Shereen A Saleh mohamed m Salama marwan m Alhusseini Ghada A mohamed Gastroenterology and Hepatology Unit Department of Internal MedicineFaculty of MedicineAin Shams UniversityCairo 11341Egypt

BACKGROUND Assessing liver fibrosis is important for predicting the efficacy of direct-acting antivirals(DAAs)and patient ***-invasive techniques to assess liver fibrosis are becoming ***,serum mac-2 binding protein glycosylation isomer(m2BPGi)was identified as a non-invasive marker of liver *** To investigate the diagnostic accuracy of m2BPGi in assessing liver fibrosis in patients with chronic hepatitis C(CHC)treated with *** From December 2017 to August 2018,80 treatment-naive adult patients with CHC who were eligible for DAAs therapy were consecutively enrolled in this observational cohort *** 12 weeks,65 patients were treated with sofosbuvir/daclatasvir,and 15 patients were treated with sofosbuvir/daclatasvir and a weight-based dose of ribavirin at knowledge and technology association for hepatitis C management clinic,Cairo,*** measured serum m2BPGi levels,PAPAS index,fibrosis-4(FIB-4)score and liver stiffness measurements(LSm)at baseline and 12 weeks after the end of *** m2BPGi levels were measured using enzyme-linked immunosorbent *** All patients achieved sustained virologic response(SVR12)(100%).Serum m2BPGi levels,LSm,FIB-4 score and PAPAS index decreased significantly at SVR12(Pm m2BPGi levels correlated positively with LSm at baseline and SVR12(Pmpared with the FIB-4 score and PAPAS index,m2BPGi was the best marker to distinguish patients with grade F4 fibrosis(AUC=0.801,Pm grade F0-1 fibrosis(AUC=0.713,P=0.012),patients with grade F3-4 from grade F0-2 fibrosis(AUC=0.730,Pm grade F0-1 fibrosis(AUC=0.763,Pm2BPGi had the greatest AUCs for differentiating patients with grade F4 fibrosis(AUC=0.844,Pm grade F0-2 fibrosis(AUC=0.893,P=0.002),patients with grade F3-4 from grade F0-2 fibrosis(AUC=0.891,P<0.001),and patients with grad

关键词： Hepatitis C virus Liver fibrosis Human mac-2 binding protein Antiviral agents Sustained virologic response Elastography

T_(m)-Eigenvalues of Odd-Order Tensors

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Communications on Applied mathematics and Computation 2022年第4期4卷 1258-1279页

作者： m.Pakmanesh Hamidreza Afshin Department of mathematics Vali-e-Asr University of RafsanjanRafsanjanIran

In this paper,we propose a definition for eigenvalues of odd-order tensors based on some ***,we define the Schur form and the Jordan canonical form of such tensors,and discuss commuting families of ***,we prove some e... 详细信息

关键词： T_(m)-product T_(m)-eigenvalue T_(m)-Schur form T_(m)-Jordan canonical form Odd-order tensor F_(m)-upper(lower)triangular tensor

S-band low noise amplifier using 1μm InGaAs/InAlAs/InP pHEmT

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Journal of Semiconductors 2012年第2期33卷 58-63页

作者： Z.Hamaizia N.Sengouga m.C.E.Yagoub m.missous Laboratory of materials Semiconductors and metallic University of Med Khider RF and microwave Research Group School of Electrical Engineering and Computer ScienceUniversity of OttawaOttawa ONKIN 6N5 Canada microelectronic & Nanostructure Group School of Electric and Electronic EngineeringUniversity of ManchesterUK

This paper discusses the design of a wideband low noise amplifier（LNA） in which specific architecture decisions were made in consideration of system-on-chip implementation for radio-astronomy *** LNA design is based on a novel ultra-low noise InGaAs/InAlAs/InP *** and non-linear modelling of this pHEmT has been used to design an LNA operating from 2 to 4 GHz.A common-drain in cascade with a common source inductive degeneration,broadband LNA topology is proposed for wideband *** proposed configuration achieved a maximum gain of 27 dB and a noise figure of 0.3 dB with a good input and output return loss（S11〈—10 dB,S22〈—11 dB）.This LNA exhibits an input 1-dB compression point of-18 dBm,a third order input intercept point of 0 dBm and consumes 85 mW of power from a 1.8 V supply.

关键词： HEmT InGaAs InP SKADS telescope LNA

Regenerative capacity of müller cells and their modulation as a tool to treat retinal degenerations

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Neural Regeneration Research 2023年第1期18卷 139-140页

作者： Federica m.Conedera Volker Enzmann Advanced microscopy Program Center for Systems BiologyMassachusetts General HospitalBostonMAUSA Wellman Center for Photomedicine Massachusetts General HospitalBostonMAUSA(Conedera FM)Department of OphthalmologyUniversity HospitalUniversity of BernBernSwitzerland Department of Biomedical Research University of BernBernSwitzerland

Vision is one of our most precious senses,and its impairment has a high socio-economic *** the industrialized world,degenerative diseases of the retina lead to vision loss,particularly among the *** degenerations include,for instance,retinitis pigmentosa,age-related macular degeneration,and diabetic *** treatments are evolving to manage late-stage symptoms of retinal degenerations,no effective therapies to recover vision loss *** degeneration often involves loss or damage to specialized neural cells,such as photoreceptors,and their death stimulates the activation and proliferation of müller cells(Salman et al.,2021).

关键词： degeneration diseases impairment

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros-mañé Laia Just-Borràs marta Balanyà-Segura Aleksandra Polishchuk Laura Nadal marta Tomàs Carolina Silvera-Simón manel m.Santafé maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

Additive neurorestorative effects of exercise and docosahexaenoic acid intake in a mouse model of Parkinson’s disease

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Neural Regeneration Research 2025年第2期20卷 574-586页

作者： Olivier Kerdiles méryl-Farelle Oye mintsa mi-mba Katherine Coulombe Cyntia Tremblay VincentÉmond martine Saint-Pierre Clémence Rouxel Line Berthiaume Pierre Julien Francesca Cicchetti Frédéric Calon Facultéde pharmacie UniversitéLaval1050 Avenue de la MédecineQuebecQCCanada Axe Neuroscience Centre de recherche du CHU de Québec-UniversitéLaval(Pavillon CHUL)2705 Boulevard LaurierQuebecQCCanada Institute of Nutrition and Functional Foods QuebecQCCanada Optinutribrain International Associated Laboratory(NutriNeuro FranceINAFCanada)QuebecQCCanada Axe Endocrinologie et Néphrologie Centre de recherche du CHU de Québec-UniversitéLavalQuebecQCCanada Département de médecine Facultéde MédecineUniversitéLavalQuebecQCCanada Département de Psychiatrie et Neurosciences Facultéde MédecineQuebecQCCanada

There is a need to develop interventions to slow or reverse the degeneration of dopamine neurons in Parkinson’s disease after *** that preclinical and clinical studies suggest benefits of dietary n-3 polyunsaturated fatty acids,such as docosahexaenoic acid,and exercise in Parkinson’s disease,we investigated whether both could synergistically interact to induce recovery of the dopaminergic ***,mice received a unilateral stereotactic injection of 6-hydroxydopamine into the striatum to establish an animal model of nigrostriatal *** weeks after lesion,animals were fed a docosahexaenoic acid-enriched or a control diet for the next 8 *** this period,the animals had access to a running wheel,which they could use or *** acid treatment,voluntary exercise,or the combination of both had no effect on(i)distance traveled in the open field test,(ii)the percentage of contraversive rotations in the apomorphine-induction test or(iii)the number of tyrosine-hydroxylase-positive cells in the substantia nigra pars ***,the docosahexaenoic acid diet increased the number of tyrosine-hydroxylase-positive terminals and induced a rise in dopamine concentrations in the lesioned *** to docosahexaenoic acid treatment or exercise alone,the combination of docosahexaenoic acid and exercise(i)improved forelimb balance in the stepping test,(ii)decreased the striatal DOPAC/dopamine ratio and(iii)led to increased dopamine transporter levels in the lesioned *** present results suggest that the combination of exercise and docosahexaenoic acid may act synergistically in the striatum of mice with a unilateral lesion of the dopaminergic system and provide support for clinical trials combining nutrition and physical exercise in the treatment of Parkinson’s disease.

关键词： 6-hydroxydopamine dopamine dopamine transporter exercise neurorestoration Parkinson’s disease polyunsaturated fatty acids omega-3