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A dynamic study of explosive cyclogeneses developments over the ocean

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海洋预报 2001年第Z1期18卷 58-66页

作者： Yonggang Zhang(张永刚) Chengzhi Sun(孙成志) Meizhong Lu(吕美仲) Ziji Ouyang(欧阳子济) Dalian Naval Submarine College，Marine Meteorology section，Dalian China Dalian Naval Submarine College，Marine Meteorology Section，DalianChina Force Meteorology College，Dynamic Meteorology Section.Nanjing.China Force Meteorology College，Dynamic Meteorology Section.Nanjing.China

A diagnostic analysis of two explosive cyclogeneses and one general cyclone over the North- west Pacific Ocean in 1979 is presented by potential vorticity and E-P flux. The analysis results demon- strate that main dynamic mechanism of explosive cyclogenesis development is upper-layer forcing action and large condensation latent heatproduced by lower-layer aqueous vapour transportation.

关键词： explosive cyclogenesis, potential vorticity, E-P flux diagnostic analysis.

Comparing the behavior of orbits in different 3D dynamical models for elliptical galaxies

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Research in Astronomy and Astrophysics 2012年第4期12卷 383-399页

作者： Euaggelos E.Zotos Department of Physics Section of Astrophysics Astronomy and Mechanics Aristotle University of Thessaloniki 541 24 Thessaloniki Greece

We study the behavior of orbits in two different galactic dynamical models, describing the motion in the central parts of a triaxial elliptical galaxy with a dense nucleus. Numerical experiments show that both models display regular motion together with extended chaotic regions. A detailed investigation of the properties of motion is made for the 2D and 3D Hamiltonian systems, using a number of different dynamical parameters, such as the Poincare′ surface of a section, the maximal Lyapunov Characteristic Exponent, the S（c） spectrum, the S（w） spectrum and the P （f ） indicator. The numerical calculations suggest that the properties of motion in both potentials are very similar. Our results show that one may use different kinds of gravitational potentials in order to describe the motion in triaxial galaxies while obtaining quantitatively similar results.

关键词： galaxies kinematics and dynamics-- galaxies elliptical

The symmetry group and harmonic potentials of an electrostatic generalized multipole

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Science China Mathematics 1995年第8期38卷 963-973页

作者：李钰 Research section of Applied Physics East China University of Technology Shanghai 200093 China

The concept of an electrostatic ordinary multipole has been extended to an electrostatic generalized multipole which consists of a pair of close placed electrostatic ordinary multipole and electrostatic round lens. The definition of the M function for an electrostatic ordinary multipole has been extended to that of the M function for an electrostatic generalized multipole. The relation between the symmetry group of anelectrostaticordinary multipole and that of its corresponding electrostatic generalized multipole, and the relation between their constraint relations among their mth partial harmonic potentials have been derived. By analyzing some important electrostatic generalized multipoles, it is concluded that if an electrostatic deflector-multipole and an electrostatic round lens are placed close to each other , one cannot assert that this combined system can always be treated by the aberration theory of a combined focusing-deflection system.

关键词： electron optics symmetry group.

Analysis of PC6 window function using fractional Fourier transform

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光电工程 2018年第6期45卷 60-68页

作者： Navdeep Goel Jaspinder Kaur Electronics and Communication Engineering section Yadavindra College of Engineering Talwandi Sabo 151302 India

Fractional Fourier transform(FRFT)is a linear transform generalizing Fourier transform(FT)that plays an important role in the field of signal processing and *** contains an adjustable parameterα,which it rotates the signal in the time frequency plane and represents the signal in an intermediate domain between time and *** provides a measure about the angular distribution of signal’s energy in time frequency *** is a special case of FRFT when angleαis equal toπ/*** paper presents mathematical model for obtaining FRFT of PC6 window *** different parameters of this window function are also obtained with the help of simulation results.A comparison of window function parameters is presented using FT and *** comparison of this window function with Hanning window function is presented in terms of Side Lobe Fall off Rate(SLFOR).For different values of FRFT order,PC6 window function shows variation in different *** by changing the FRFT order,the minimum stop band attenuation of the resulting window function can be controlled.

关键词：傅立叶变换信号函数数学模型

In search for the “idyllic” animal model to evaluate ocular pathologies and translate new therapies to improve human health

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Neural Regeneration Research 2022年第12期17卷 2697-2699页

作者： Francisco M.Nadal-Nicolás Kiyoharu J.Miyagishima Wei Li Retinal Neurophysiology section National Eye InstituteNational Institutes of HealthBethesdaMDUSA

The retina is a highly specialized neural tissue that encodes information of vision,a vital sensory modality for most *** the retina also contributes to other non‐image‐forming signals(*** of circadian clocks),vision chiefly enables animals to interpret and navigate their environment(despite the diverse variety of species and lifestyles;Baden et al.,2020)and also to interact with other ***,features such as high visual resolution and color discrimination are important for interactive behaviors like prey capture and also for social animals,including primates,that establish a dominance *** vertebrates,the laminar structure of the retina is notably *** photoreceptor layer(rods and cones)initiates the process of converting light energy into nerve impulses by absorbing photons and transferring the signals to interneurons.

关键词： laminar enable absorbing

Prevalence and associated factors of obesity in inflammatory bowel disease:A case-control study

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World Journal of Gastroenterology 2020年第47期26卷 7528-7537页

作者： Giuseppe Losurdo Rosa Federica La Fortezza Andrea Iannone Antonella Contaldo Michele Barone Enzo Ierardi Alfredo Di Leo Mariabeatrice Principi section of Gastroenterology Department of Emergency and Organ TransplantationUniversity of BariBari 70124Italy

BACKGROUND In recent years,an increasing prevalence of obesity in inflammatory bowel disease(IBD)has been ***,moreover,has been directly correlated with a more severe clinical course and loss of response to *** To assess the prevalence and associated factors of obesity in *** We collected data about IBD disease pattern and activity,drugs and laboratory investigations in our *** measures were retrieved and obesity defined as a body mass index(BMI)>***,we compared characteristics of obese vs non obese patients,and Chi-squared test and Student’s t test were used for discrete and continuous variables,respectively,at univariate *** multivariate analysis,we used binomial logistic regression and estimated odd ratios(OR)and 95%confidence intervals(CI)to ascertain factors associated with *** We enrolled 807 patients with IBD,either ulcerative colitis(UC)or Crohn’s disease(CD).Four hundred seventy-four patients were male(58.7%);the average age was 46.2±13.2 years;438(54.2%)patients had CD and 369(45.8%)*** enrolled 378 controls,who were comparable to IBD group for age,sex,BMI,obesity,diabetes and abdominal circumference,while more smokers and more subjects with hypertension were observed among *** prevalence of obesity was 6.9%in IBD and 7.9%in controls(not statistically different;P=0.38).In the comparison of obese IBD patients and obese controls,we did not find any difference regarding diabetes and hypertension prevalence,nor in sex or smoking *** IBD patients were younger than obese controls(51.2±14.9 years vs 60.7±12.1 years,P=0.03).At univariate analysis,obese IBD were older than normal weight ones(51.2±14.9 vs 44.5±15.8,P=0.002).IBD onset age was earlier in obese population(44.8±13.6 vs 35.6±15.6,P=0.004).We did not detect any difference in disease *** subjects had consumed more frequently long course of systemic steroids(66.6%vs 12.5%,P=0.02)as well as antibiotics s

关键词： Inflammatory bowel disease Obesity Body mass index Antibiotics Risk factor Corticosteroids

Stool characteristics of infants receiving short-chain galactooligosaccharides and long-chain fructo-oligosaccharides:A review

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World Journal of Gastroenterology 2014年第37期20卷 13446-13452页

作者： Petra AMJ Scholtens Dominique AM Goossens Annamaria Staiano Nutricia Research section of Pediatrics Department of Translation Medical ScienceFederico ⅡUniversity of Naples

Human milk is considered to be the optimal source of infant nutrition. Some of the benefits of breastfeeding have been ascribed to human milk oligosaccharides(HMO). For instance, HMO can affect faecal characteristics such as stool consistency and stool frequency. Such effects on stool characteristics can be beneficial for young infants as hard stools and even constipation is common in that age group. Prebiotics in infant milk formulas have been introduced to exert similar functionalities. A specific mixture of prebiotics consists of a combination of short chain galacto-oligosaccharides and long-chain fructo-oligosaccharides(scGOS/lcFOS) in a ratio of 9:1. This specific mixture has been developed to closely resemble the molecular size composition of HMO. Many studies have been done with scGOS/lcFOS, and indicators for digestive comfort have often been included as secondary outcomes. This review summarizes the effects of scGOS/lcFOS(9:1) on stool consistency,stool frequency and transit time in healthy term and preterm infants. In several of the studies with scGOS/lcFOS in a ratio of 9:1 in infant milk formulas, positive effects of this mixture on stool characteristics such as stool consistency and stool frequency were observed. As stool consistency was shown to be correlated to whole gut transit time, scGOS/lcFOS can be hypothesised to have a role in reducing the risk of constipation.

关键词： Short-chain galactooligosaccharides Long-chain fructooligosaccharides Stool consistency Stool frequency Infants

Extraordinary sneeze:Spontaneous transmaxillarytransnasal discharge of a migrated dental implant

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World Journal of Clinical Cases 2016年第8期4卷 229-232页

作者： Pasquale Procacci Daniele De Santis Dario Bertossi Massimo Albanese Cristina Plotegher Giovanni Zanette Alessia Pardo Pier Francesco Nocini section of Oral and Maxillofacial Surgery Department of Surgery University of Verona

This case report describes an extraordinary case of the spontaneous transmaxillary-transnasal discharge of a dental implant, which occurred during a sneeze. The patient was complained of symptoms of acute sinusitis. She underwent a computed tomography scan that revealed a dental implant dislocated in the maxillary sinus. Medical treatment based on antibiotics and mucolytics was administered to the patient in order to prepare her for endoscopic endonasal surgery. The implant was spontaneously discharged two days after during a sneeze. Mucociliary clearance in combination with a local osteolytic inflammatory process and mucolytics therapy are the likely causes of this unusual discharge.

关键词： Complications Dental implant Acute sinusitis Implant surgery

The nature of orbits in a prolate elliptical galaxy model with a bulge and a dense nucleus

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Research in Astronomy and Astrophysics 2011年第12期11卷 1449-1456页

作者： Nicolaos D.Caranicolas Euaggelos E.Zotos Department of Physics Section of AstrophysicsAstronomy and MechanicsAristotle University of Thessaloniki 541 24ThessalonikiGreece

We study the transition from regular to chaotic motion in a prolate elliptical galaxy dynamical model with a bulge and a dense nucleus. Our numerical investigation shows that stars with angular momentum Lz less than or equal to a critical value Lzc, moving near the galactic plane, are scattered to higher z, when reaching the central region of the galaxy, thus displaying chaotic motion. An inverse square law relationship was found to exist between the radius of the bulge and the critical value Lzc of the angular momentum. On the other hand, a linear relationship exists between the mass of the nucleus and Lzc. The numerically obtained results are explained using theoretical arguments. Our study shows that there are connections between regular or chaotic motion and the physical parameters of the system, such as the star＇s angular momentum and mass, the scale length of the nucleus and the radius of the bulge. The results are compared with the outcomes of previous work.

关键词： galaxies: kinematics and dynamics