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bifurcation analysis of a discrete Phytoplankton-Zooplankton model with linear predational response function and toxic substance distribution

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International Journal of biomathematics 2023年第4期16卷 81-101页

作者： A.Q.Khan F.Nazir m.b.almatrafi Departmentof mathematics University of Azad Jammu and Kashmir muzaffarabad 13100 Pakistan Department of mathematics College of Science Taibah University Al-Madinah Al-MunawarahSaudi Arabia

Phytoplanktons are drifting plants in an aquatic system.They provide food for marine animals and are compared to terrestrial plants in that having chlorophyll and carrying out photosynthesis.Zooplanktons are drifting animals found inside the aquatic bodies.For stable aquatic ecosystem,the growth of both Zooplankton and Phytoplankton should be in steady state but in previous eras,there has been a universal explosion in destructive Plankton or algal blooms.many investigators used various mathematical methodologies to try to explain the bloom phenomenon.So,in this paper,a discretized two-dimensional Phytoplankton-Zooplankton model is investigated.The results for the existence and uniqueness,and conditions for local stability with topological classifications of the equilibrium solutions are determined.It is also exhibited that at trivial and semitrivial equilibrium solutions,discrete model does not undergo fip bifurcation,but it undergoes Neimark-Sacker bifurcation at interior equilibrium solution under certain conditions.Further,state feedback method is deployed to control the chaos in the under consideration system.The extensive numerical simulations are provided to demonstrate theoretical results.

关键词： Discrete model numerical simulation bifurcations chaos

Analytical and Numerical Investigation for the Dmbbm Equation

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Computer modeling in Engineering & Sciences 2020年第2期122卷 743-756页

作者： Abdulghani Alharbi mahmoud A.E.Abdelrahman m.b.almatrafi Department of mathematics College of ScienceTaibah UniversityAl-Madinah Al-MunawarahSaudi Arabia. Department of mathematics Faculty of ScienceMansoura UniversityMansouraEgypt.

The nonlinear dispersive modified benjamin-bona-mahony(Dmbbm)equation is solved numerically using adaptive moving mesh PDEs(mmPDEs)method.Indeed,the exact solution of the Dmbbm equation is obtained by using the extended Jacobian elliptic function expansion method.The current methods give a wider applicability for handling nonlinear wave equations in engineering and mathematical physics.The adaptive moving mesh method is compared with exact solution by numerical examples,where the explicit solutions are known.The numerical results verify the accuracy of the proposed method.

关键词： Dmbbm equation Jacobian elliptic functions moving mesh PDEs(mmPDEs) moving adaptive scheme solitary waves.

Soils in extraterrestrial space: Need for studies under microgravity

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Pedosphere 2024年第1期34卷 13-14页

作者： m.b.KIRKHAm Department of Agronomy Kansas State UniversityManhattan KS 66506USA

With the increased interest of plants in space, gravity cannot be ignored when studying soil-plant-water relations. Therefore, it is important to understand the water relations of soils under zero gravity in space or under reduced gravity on the moon or mars. This paper outlines the problems of moving water in soils under zero gravity or microgravity, as well as growing plants in these soils. It is suggested that microgravity experiments could be done on Earth using both soils and plants. Results from such experiments could be used to grow plants when mankind establishes bases on the moon and mars.

关键词： soils soil bases

Global Stability Analysis of the mathematical model for malaria Transmission between Vector and Host Population

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American Journal of Computational mathematics 2024年第2期14卷 275-289页

作者： Raghad Alsulami Amal almatrafi Nehad Almohammadi Hanin Alosaimi H. A. batarfi Department of mathematics Faculty of Science King Abdulaziz University Jeddah Kingdom of Saudi Arabia

In this paper, we discuss a mathematical model of malaria transmission between vector and host population. We study the basic qualitative properties of the model, the boundedness and non-negativity, calculate all equilibria, and prove the global stability of them and the behaviour of the model when the basic reproduction ratio R0 is greater than one or less than one. The global stability of equilibria is established by using Lyapunov method. Graphical representations of the calculated parameters and their effects on disease eradication are provided.

关键词： malaria Transmission Global Stability Lyapunov Function

Quantum correlations and entanglement in coupled optomechanical resonators with photon hopping via Gaussian interferometric power analysis

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Chinese Physics b 2024年第5期33卷 204-211页

作者： Y.Lahlou b.maroufi m.Daoud LPHE-mS Department of PhysicsFaculty of SciencesMohammed V UniversityRabatMorocco LPmS Department of PhysicsFaculty of SciencesIbn Tofail UniversityKénitraMorocco

Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum computation.Essentially,for quantum systems prepared in pure states,it is difficult to differentiate between quantum entanglement and quantum correlation.Nonetheless,this indistinguishability is no longer holds for mixed states.To contribute to a better understanding of this differentiation,we have explored a simple model for both generating and measuring these quantum correlations.Our study concerns two macroscopic mechanical resonators placed in separate Fabry–Pérot cavities,coupled through the photon hopping process.this system offers a comprehensively way to investigate and quantify quantum correlations beyond entanglement between these mechanical modes.The key ingredient in analyzing quantum correlation in this system is the global covariance matrix.It forms the basis for computing two essential metrics:the logarithmic negativity(E_(N)^(m))and the Gaussian interferometric power(P_(G)^(m)).These metrics provide the tools to measure the degree of quantum entanglement and quantum correlations,respectively.Our study reveals that the Gaussian interferometric power(P_(G)^(m))proves to be a more suitable metric for characterizing quantum correlations among the mechanical modes in an optomechanical quantum system,particularly in scenarios featuring resilient photon hopping.

关键词： quantum correlations entanglement Gaussian interferometric power logarithmic negativity optomechanics photon hopping

Complexed amino acid minerals vs. bis-glycinate chelated minerals:Impact on the performance of old laying hens

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Animal Nutrition 2024年第1期16卷 395-408页

作者： marcos J.b.Santos maria C.m.m.Ludke Leandro m.Silva Carlos b.V.Rabello mércia R.barros Fabiano S.Costa Clariana S.Santos Jamille S.S.Wanderley Department of Animal Science Rural Federal University of Pernambuco Department of Veterinary Science Rural Federal University of Pernambuco

The present study was to evaluate the effect of trace minerals(Zn, mn, and Cu) from complexed amino acid minerals(ZmCAA) and bis-glycinate chelated minerals(ZmCGly) in laying hen diets on performance,internal and external egg quality, yolk mineral deposition, intestinal morphometry, and bone characteristics. From 78 to 98 weeks of age, 400 White LSL-Lite strain laying hens were distributed in a randomized design with 4 treatments with 10 replicates per treatment. Treatments were distributed in a 2 ×2 factorial arrangement using either Zn, mn, and Cu of ZmCAA or ZmCGly source at 2 levels: low(20, 20,and 3.5 mg/kg of Zn, mn, and Cu, respectively) or high(40, 40, and 7 mg/kg of Zn, mn, and Cu,respectively). The analysis of variance was performed, and in cases where differences were observed, the means were compared using Tukey?s test(P mineral supplementation had a significant impact on the performance of laying hens. Hens fed ZmCAA had higher egg production(P = 0.01), egg weight(P = 0.02), egg mass(P = 0.01), and lower feed conversion ratio(P =0.05) compared to those fed ZmCGly. The ZmCAA supplementation showed higher albumen height(P =0.01), albumen weight(P = 0.01), and eggshell thickness(P mn(PmCAA. Tibia weight(P = 0.04)and bone densitometry(P bia were higher with ZmCAA supplementation. In the small intestine, ZmCAA resulted in longer villi(P = 0.02) and shorter crypt depth(P = 0.01) in the duodenum.Jejunum and ileum measurements were influenced by the level and source of trace minerals(P mCAA exhibited superior performance, egg quality, deposition of trace minerals in the egg yolk, and bone density compared to hens fed ZmCGly. In this study, older laying hens supplemented with ZmCAA at lower levels demonstrated adequate levels of supplementation.

关键词： bis-glycinates metal-amino acids Radiodensity Trace minerals

Direct microwave leaching conditions of rare earth elements in fluorescent wastes

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Journal of Rare Earths 2024年第6期42卷 1165-1174,I0007页

作者： A.bilen b.birol m.N.Saridede S.S.Kaplan m.S.Sonmez Department of metallurgical and materials Engineering Yildiz Technical UniversityIstanbulTurkey Department of Chemical Engineering and materials Science Stevens Institute of TechnologyNew JereyUSA Department of metallurgical and materials Engineering Istanbul Technical UniversityIstanbulTurkey

The luminescent phosphor powder in the fluorescent lamp constitutes 2%of the lamp’s weight.It can be mentioned that fluorescent wastes are a crucial raw material to produce rare earth oxides.In the present study,microwave leaching process was conducted to dissolve rare earth elements yttrium(Y),europium(Eu),and remaining rare earth elements(REEs)present in the phosphor powder of the fluorescent lamp.and the yields were compared.In the microwave leaching process,the effects of the temperature(80-160℃),acid type(hydrochloric acid(HCl),nitric acid(HNO_(3)),sulphuric acid(H_(2)SO_(4))),acid concentration(0.5-6 mol/L),solid to liquid ratio(0.1:10-0.5:10)and reaction time(5-90 min)parameters on leaching efficiencies of varying rare earth elements and calcium were investigated.The highest yield was obtained in the direct microwave leaching of fluorescent waste with the experimental conditions of 6 mol/L HCl,160℃,0.1:10 solid-to-liquid ratio(S:L),and 90 min.Activation energy calculations were made,and kinetic models of the reactions were obtained,and it is observed that Y and Eu dissolution is diffusion-controlled,on the other hand,lanthanum(La),cerium(Ce),and terbium(Tb)were examined to be chemical reaction controlled.moreover,calcium(Ca)and gadolinium(Gd)seem coherent with the mixed model.Concurrently,mathematical models of all experimental studies are created with the response surface box-behnken method and the correlation coefficients of all the models are over 90%.

关键词： Rare earth elements(REEs) Direct microwave leaching Fluorescent waste Kinetic models Response surface method

Semi-analytical investigation of heat transfer in a porous convective radiative moving longitudinal fin exposed to magnetic field in the presence of a shape-dependent trihybrid nanofluid

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Applied mathematics and mechanics(English Edition) 2024年第1期45卷 197-216页

作者： C.G.PAVITHRA b.J.GIREESHA m.L.KEERTHI Department of PG Studies and Research in mathematics Kuvempu UniversityShankaraghatta 577451India Department of mathematics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The thermal examination of a non-integer-ordered mobile fin with a magnetism in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The combination approach is utilized to evaluate the physical and thermal characteristics of the trihybrid and hybrid nanofluids, excluding the thermal conductivity and dynamic viscosity. These two properties are inferred by means of the interpolation method based on the volume fraction of nanoparticles. The governing equation is transformed into a dimensionless form, and the Adomian decomposition Sumudu transform method(ADSTm) is adopted to solve the conundrum of a moving fin immersed in a trihybrid nanofluid. The obtained results agree well with those numerical simulation results, indicating that this research is reliable. The influence of diverse factors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furthermore, the fluctuations in the heat transfer concerning the pertinent parameters are studied. The results show that the heat flux in the presence of the combination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the combination of only spherical and cylindrical nanoparticles. The temperature at the fin tip increases by 0.705 759% when the value of the Peclet number increases by 400%, while decreases by 11.825 13% when the value of the Hartman number increases by 400%.

关键词： convection radiation moving longitudinal fin Adomian decomposition Sumudu transform method(ADSTm) trihybrid nanofluid magnetic field

multi-aspect analysis of ureteral access sheath usage in retrograde intrarenal surgery: A RIRSearch group study

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Asian Journal of Urology 2024年第1期11卷 80-85页

作者： Oktay Özman Hacı m.Akgül Cem başataç Önder Çınar Eyüp b.Sancak Cenk m.Yazıcı bülent Önal Haluk Akpınar Gaziosmanpasa Training and Research Hospital Urology ClinicİstanbulTurkey TekirdağNamık Kemal University School of MedicineDepartment of UrologyTekirdağTurkey Group Florence Nightingale Hospitals Department of UrologyİstanbulTurkey Zonguldak bulent Ecevit University School of MedicineDepartment of UrologyZonguldakTurkey Çanakkale Onsekiz mart University School of MedicineDepartment of UrologyÇanakkaleTurkey İstanbul University-Cerrahpaşa Cerrahpaşa Medical FacultyDepartment of UrologyİstanbulTurkey

Objective:To evaluate the effect of ureteral access sheath(UAS)use and calibration change on stone-free rate and complications of retrograde intrarenal surgery(RIRS).methods:Data from 568 patients undergoing RIRS for kidney or upper ureteral stones were retrospectively included.Firstly,patients were compared after 1:1 propensity score matching,according to UAS usage during RIRS(UAS used[+]87 and UAS non-used[−]87 patients).Then all UAS+patients(n=481)were subdivided according to UAS calibration:9.5-11.5 Fr,10-12 Fr,11-13 Fr,and 13-15 Fr.Primary outcomes of the study were the success and complications of RIRS.Results:Stone-free rate of UAS+patients(86.2%)was significantly higher than UAS−patients(70.1%)after propensity score matching(p=0.01).Stone-free rate increased with higher caliber UAS(9.5-11.5 Fr:66.7%;10-12 Fr:87.0%;11-13 Fr:90.6%;13-15 Fr:100%;pmplications of UAS+patients(11.5%)were significantly lower than UAS−patients(27.6%)(p=0.01).Complications(8.7%)with 9.5-11.5 Fr UAS was lower than thicker UAS(17.2%)but was not statistically significant(p=0.09).UAS usage was an independent factor predicting stone-free status or peri-and post-operative complications(odds ratio[OR]3.654,95%confidence interval[CI]1.314-10.162;OR 4.443,95%CI 1.350-14.552;OR 4.107,95%CI 1.366-12.344,respectively).Conclusion:Use of UAS in RIRS may increase stone-free rates,which also increase with higher caliber UAS.UAS usage may reduce complications;however,complications seemingly increase with higher UAS calibration.

关键词： Stone Retrograde intrarenal surgery Ureteral access sheath Urolithiasis Kidney