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Dual-Core Photonic Crystal Fiber Plasmonic Refractive Index Sensor: A Numerical Analysis

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Photonic Sensors 2019年第2期9卷 151-161页

作者： Alok Kumar paul Ajay Krishno SARKAR Department of Electrical & Electronic Engineering Rajshahi University of Engineering & Technology Rajshahi-6204 Bangladesh

A numerical analysis on dual core photonic crystal fiber (DC-PCF) based surface plasmon resonance (SPR) refractive index sensor is presented. The guiding parameters and required sensing performances are examined with finite element method (FEM) based software under MATLAB environment. According to simulation, it is warranted that the proposed refractive index sensor offers the maximum amplitude sensitivity of 554.9 refractive index unit (RIU-1) and 636.5 RIU 1 with the maximum wavelength sensitivity of 5800nm/RIU and 11 500nm/RIU, and the sensor resolutions of 1.72 ×10^-5RIU and 8.7× 10^-6 RIU, at analyte refractive index (RI) of 1.40 for x- and y-polarized modes, respectively. As the sensing performance in different wavelength ranges is quite high, the proposed sensor can be used in simultaneous detection for different wavelength ranges. Therefore, the proposed device is of a suitable platform for detecting biological, chemical, biochemical, and organic chemical analytes.

关键词： Photonic crystal fiber biosensor refractive index sensor finite element method plasmonic material

Pathobiology of the neutrophil-intestinal epithelial cell interaction:Role in carcinogenesis

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World Journal of Gastroenterology 2010年第46期16卷 5790-5800页

作者： paul M Hofman Laboratory of Clinical Experimental PathologyHuman BiobankUniversity of Nice Sophia Antipolis

The role of chronic inflammation,acting as an independent factor,on the onset of gastrointestinal carcinogenesis is now well ***,even if there is an increase in the number of elements directly involving polymorphonuclear leukocytes (PMNL),as a major actor in digestive carcinogenesis,the different cellular and molecular events occurring in this process are still not completely *** transepithelial migration of PMNL,which is the ultimate step of the afflux of PMNL into the digestive mucosa,is a complex phenomenon involving sequential interaction of molecules expressed both on PMNL and on digestive epithelial *** inflammatory areas rich in PMNL [so-called (chronic active inflammation)] and iterative transepithelial migration of PMNL certainly evoke intracellular signals,which lead toward progressive transformation of *** these different signals,the mutagenic effect of reactive oxygen species and nitrates,the activation of the nuclear factor-κB pathway,and the modulation of expression of certain microRNA are key *** the initiation of carcinogenesis,PMNL are involved in the progression and invasion of digestive carcinomas,with which they *** is noteworthy that different subpopulations of PMNL,which can have some opposite effects on tumor growth,in association with different levels of transforming growth factor-β and with the number of CD8 positive T lymphocytes,could be present during the development of digestive *** factors that involve PMNL,such as massive elastase release,and the production of angiogenic factors,can participate in the progression of neoplastic cells through *** may play a major role in the onset of metastases,since they allow the tumor cells to cross the endothelial barrier and to migrate into the blood ***,PMNL play a role,alone or in association with other cell parameters,in the initiation,promotion,progression and dissemination of digestive carcinomas.

关键词： Neutrophils Intestinal epithelial cells Carcinogenesis Cytokines Nuclear factor-κB pathway MicroRNA Reactive oxygen species

Tensor perturbations from bounce inflation scenario in f(Q)gravity

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 78-92页

作者： Kun Hu Tanmoy paul Taotao Qiu Institute of Astrophysics Central China Normal UniversityWuhan 430079China School of Physics Huazhong University of Science and TechnologyWuhan 430074China National Institute of Technology Jamshedpur Department of PhysicsJamshedpur 831014India

In this paper,we construct a bounce inflation cosmological scenario in the framework of the modified symmetric teleparallel gravity,namely f(Q)theory,and investigate the tensor perturbations *** is well-known,the tensor perturbations generated in the very early Universe(inflation and pre-inflation regions)can account for the primordial gravitational waves(PGWs)that are to be detected by the next generation of GW *** discuss the stability condition of the tensor perturbations in the bounce inflation process and investigate in detail the evolution of the perturbation *** general form of the tensor power spectrum is obtained both for large as well as small scale *** a result,we show both kinds of modes(short or long wavelength modes),and the tensor spectrum may get a positive tilt in the parametric range where the tensor perturbation proves to be stable—this interestingly hints an enhancement of gravitational waves’amplitude in the background of the f(Q)bounce-inflation ***,we study the LQC-like scenario as a specific case of our model,in which,the primordial tensor power spectrum turns out to be nearly scale-invariant on both small and large scales.

关键词： bounce cosmology modified gravity cosmological perturbations

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Chronic kidney disease and the skeleton

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Bone Research 2014年第4期2卷 205-217页

作者： paul D Miller Colorado Center for Bone Research LakewoodCO.USA

Fractures across the stages of chronic kidney disease （CKD） could be due to osteoporosis, some form of renal osteodystrophy defined by specific quantitative histomorphometry or chronic kidney disease-mineral and bone disorder （CKD-MBD）. CKD-MBD is a systemic disease that links disorders of mineral and bone metabolism due to CKD to either one or all of the following： abnormalities of calcium, phosphorus, parathyroid hormone or vitamin D metabolism; abnormalities in bone turnover, mineralization, volume, linear growth or strength; or vascular or other soft-tissue calcification. Osteoporosis, as defined by the National Institutes of Health, may coexist with renal osteodystrophy or CKD-MBD. Differentiation among these disorders is required to manage correctly the correct disorder to reduce the risk of fractures. While the World Health Organization （WHO） bone mineral density （BMD） criteria for osteoporosis can be used in patients with stages 1-3 CKD, the disorders of bone turnover become so aberrant by stages 4 and 5 CKD that neither the WHO criteria nor the occurrence of a fragility fracture can be used for the diagnosis of osteoporosis. The diagnosis of osteoporosis in stages 4 and 5 CKD is one of the exclusion--excluding either renal osteodystrophy or CKD- MBD as the cause of low BMD or fragility fractures. Differentiations among the disorders of renal osteodystrophy, CKD-MBD or osteoporosis are dependent on the measurement of specific biochemical markers, including serum parathyroid hormone （PTH） and/or quantitative bone histomorphometry. Management of fractures in stages 1-3 CKD does not differ in persons with or without CKD with osteoporosis assuming that there is no evidence for CKD-MBD, clinically suspected by elevated PTH, hyperphosphatemia or fibroblast growth factor 23 due to CKD. Treatment of fractures in persons with osteoporosis and stages 4 and 5 CKD is not evidence-based, with the exception of post-hoc analysis suggesting efficacy and safety of specific o

关键词： CKD GFR PTH MBD

Advantages of a Biomimetic Stiffness Profile in Pitching Flexible Fin Propulsion

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Journal of Bionic Engineering 2010年第2期7卷 113-119页

作者： paul Riggs Adrian Bowyer Julian Vincent Biomimetics Group Mechanical Engineering DepartmentUniversity of Bath

The use of oscillating flexible fins in propulsion has been the subject of several studies in recent years, but attention israrely paid to the specific role of stiffness profile in thrust *** profile is defined as the variation in localchordwise bending stiffness (EI) of a fin, from leading to trailing *** this study, flexible fins with a standard NACA0012shape were tested alongside fins with a stiffness profile mimicking that of a Pumpkinseed Sunfish (Lepomis gibbosus).The finswere oscillated with a pitching sinusoidal motion over a range of frequencies and amplitudes, while torque, lateral force andstatic thrust were *** the range of oscillation parameters tested, it was shown that the fin with a biomimetic stiffness profile offered a significantimprovement in static thrust, compared to a fin of similar dimensions with a standard NACA0012 aerofoil *** fin also produced thrust more consistently over each oscillation cycle.A comparison of fin materials of different stiffness showed that the improvement was due to the stiffness profile itself, andwas not simply an effect of altering the overall stiffness of the *** of the same stiffness profile were observed to follow thesame thrust-power curve, independent of the stiffness of the moulding *** fins were shown to produce up to26% greater thrust per watt of input power, within the experimental range.

关键词： biomimetic propulsion stiffness pitching flexible fin

An Efficient Approach for Simulation of Water Levels due to the Nonlinear Interaction of Tide and Surge Along the Coast of Bangladesh

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China Ocean Engineering 2020年第4期34卷 537-546页

作者： Gour Chandra paul Sukumar Senthilkumar Rana Pria Department of Mathematics University of RajshahiRajshahi-6205Bangladesh School of Mathematical Sciences Universiti Sains MalaysiaPulau Pinang-11800Malaysia Mathematics Discipline ScienceEngineering&Technology SchoolKhulna UniversityKhulna-9208.Bangladesh

The ultimate goal and highlight of this paper are to explore water levels along the coast of Bangladesh efficiently due to the nonlinear interaction of tide and surge by employing the method of lines(MOLs)with the aid of newly proposed RKAHeM(4,4)*** this regard,the spatial derivatives of shallow water equations(SWEs)were discretized by means of a finite difference method to obtain a system of ordinary differential equations(ODEs)of initial valued with time as an independent *** obtained system of ODEs was solved by the RKAHeM(4,4)***-way nested grid technique was exercised to incorporate coastal complexities closely with minimum computational cost.A stable tidal oscillation was produced over the region of interest by applying the most influential tidal constituent M2 along the southern open boundary of the outer *** newly developed model was applied to estimate water levels due to the non-linear interaction of tide and surge associated with the catastrophic cyclone April 1991 along the coast of *** approach employed in the study was found to perform well and ensure conformity with real-time observations.

关键词： method of lines RKAHeM(4 4)technique error estimation storm surge nested grid

The Potential of High Power Lasers for Tube Cutting and Concrete Scabbling in Nuclear Decommissioning

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稀有金属材料与工程 2011年第S4期40卷 252-256页

作者： paul Hilton Ali Khan TWI Ltd.Granta Park Cambridge CB21 6ALUK

Contaminated concrete and metal pipework presents a major nuclear decommissioning challenge in terms of the total volumes of material to be treated,the radiation levels present and the number of facilities *** recently,industrial lasers have often been seen as too unreliable for use in nuclear decommissioning environments and hence their usage has been *** advent of solid state 'fibre' lasers has,however,provided a robust and reliable industrial tool,capable of performing not only concrete scabbling but other laser based decommissioning processes,such as *** concrete scabbling has been demonstrated in the laboratory,to date,no representative scale demonstration has been provided which would give industry confidence in the *** paper will describe the development of a laser scabbling process head,equipped with an integrated debris collection device and adaptive control system for automatic maintenance of the attitude and stand off distance of the head from the concrete *** results of using optical fibre delivered laser power to remove the surface of a range of representative and large scale concrete samples will be *** 5kW of laser power,removal rates up to 7000 cc of concrete per hour have been recorded at a removal depth of the order *** paper will also report on the results of using the same laser source,for single-sided cutting of various 304L stainless steel tubes,of diameter up to 170mm and wall thickness up to *** results show that with the right optical configuration,it is entirely possible to laser cut tubes from one side,at extremely long and safe standoff distances,if the main objective is simply to sever the tube.

关键词： lasers concrete scabbling tube cutting.

The rise of 3D cellular spheroids: efficient culture via upward growth from a superamphiphobic surface

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National Science Review 2019年第6期6卷 1068-1069页

作者： paul J.Dyson Institut des Sciences et Ingénierie Chimiques Ecole Polytechnique Fédérale de Lausanne

Cell culture assays are extensively used in drug discovery and development programs, biomedical research, and in many others areas of science. Currently,2D monolayer cellular assays serve as the gold standard. However, while they provide seemingly indispensable information on drug activity, it is estimated that of the putative drug candidates selected

关键词： The rise of 3D cellular spheroids efficient culture via upward growth from a superamphiphobic surface

Geochemical characteristics of saturate hydrocar-bons in crude oils and source rocks of the Qaidam,Tarim,Tupran basins,NW China

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Chinese Journal Of Geochemistry 2012年第3期31卷 264-275页

作者： ZHANG Min paul Philp Department of Geochemistry Yangtze UniversityJingzhou434023China The Key Laboratory of Oil&Gas Resources and Exploration Technology Ministry of EducationYangtze UniversityJingzhou434023China School of Geology and Geophysics University of OklahomaNormanOK 73019USA

Based on the systematic analyses of fifteen typical crude oils and ten typical potential source rocks col-lected from the Qaidam,Tarim and Turpan basins,Northwest China,the geochemical characteristics of the oils and source rocks were investigated and oil-source rock correlations *** oils and source rocks deposited in saline lacustrine environment from the western Qaidam Basin were characterized by n-alkanes with even car-bon-number preference in the C20-C28 range,low pristane/phytane(Pr/Ph) ratios(less than 0.5),and high abundances of C27 steranes,gammacerane and C35 *** oils and source rocks deposited in marine environment from the Tarim Basin were characterized by n-alkanes with even carbon-number preference in the C14-C18 range,relatively low Pr/Ph ratios(near to 1),high abundance of C28 steranes,and relatively high *** contrast,the oils and source rocks deposited in terrigenous bog environment from the Turpan Basin were characterized by relatively high Pr/Ph ratios(oil samples greater than 6) high abundance of C29 steranes,and relatively low gammacerane and C31-35 *** higher amounts of C37 and C38 n-alkanes of source rocks from the western Qaidam Basin and the Tarim Basin suggest an origin of these alkanes from functionalized C37 and C38 n-alkadienes and alkenones in prymnesiophytes living in lacustrine and marine ***-source rock correlations suggest oils in the west-ern Qaidam Basin were derived from the Oligocene Lower Ganchaigou Formation(E3),oils in the Tabei and Tazhong uplifts from the Tarim Basin have a genetic relationship with the Middle-Upper Ordovician source *** in the Turpan Basin generally fall into two genetic *** oils in the Taibei depression from the Turpan Basin were derived from the Lower-Middle Jurassic coal measures,but the fewer oils in this region are a mixed source derived from the Lower-Middle Jurassic coal measure and the Upper Permian source rocks.

关键词：地球化学特征塔里木盆地柴达木盆地中国西北地区烃源岩碳氢化合物原油吐鲁番盆地