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Sharma, Anukriti, Ken B. Johnson, Alper Sen, et al. "Abstract P1-04-02: Longitudinal multi-omics study reveals potential targets against chemotherapy induced peripheral neuropathy during taxane treatment." Clinical Cancer Research 31, no. 12_Supplement (2025): P1–04–02—P1–04–02. https://doi.org/10.1158/1557-3265.sabcs24-p1-04-02.
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Abstract Background: Taxanes are effective but pose a significant clinical challenge due to the risk of chemotherapy-induced peripheral neuropathy (CIPN) that can result in treatment discontinuation or dose reduction. In a multi-omic, longitudinal study, patients with early-stage breast cancer undergoing taxane therapy as part of their (neo)adjuvant treatment regimen were evaluated over 12 months. Using selected panels of mRNAs, miRNAs, cytokines, and metabolites obtained from blood, we examined changes in molecular markers over time to elucidate biological pathways involved in CIPN and identify potential targets for therapeutic intervention. We hypothesized that a biomarker profile could be identified to track CIPN predisposition and its progression over time. Methods: 400 breast cancer patients were evaluated at 7 time points—pre (visit 1), during (visits 2-4), and after taxane chemotherapy (visits 5-7). CIPN was measured using the Chemotherapy-induced Peripheral Neuropathy 20-item (CIPN20) questionnaire. Patients with linearized CIPN20 scores (range 0-100) of 8 points above baseline at a time point were classified as having neuropathy. Panels of 194 mRNAs, 798 miRNAs, 13 cytokines, and 85 metabolites were assessed at each of the 7 time points. Changes in molecular markers from pre-treatment baseline through treatment and post-treatment phases were analyzed using a semi-parametric approach, the OmicsLonDA package. Changes in mRNA expression over time were used to examine the activation (Z score > 0) and inhibition (Z score < 0) of selected molecular pathways associated with CIPN, mapped using Ingenuity Pathway Analyses (IPA). Results: 99 mRNAs, 55 miRNAs, and 10 metabolites showed significant differences between patients with and without CIPN over six time intervals; no significant differences were found for the cytokine panel (P>.05). For example, among the mRNAs, expression of OPRM1 was significantly higher in the CIPN negative group from visit 3 to 7 (int3-7), while expression of CAMK1D mRNA was significantly higher in the CIPN positive group for int2-6 (FDR P<.05). Among the miRNA candidates, miR.31.5p.0 was significantly higher in the CIPN negative group for int3-6, whereas miR.184.0 was significantly higher in the CIPN positive group for int6-7 (FDR P<.05). Among the 10 statistically significant metabolites, tyrosine was significantly higher in the CIPN positive group compared to the CIPN negative group for int2-7 (FDR P<.05). Total 99 significant mRNA candidates were identified in 120 pathways over time, including 18 genes in cAMP-response element binding protein (CREB) signaling, 14 in opioid signaling, 6 in neuropathic pain signaling, and 10 in endocannabinoid neuronal synapse pathways. Additionally, interval-specific (i.e. between visits) comparative analyses of these pathways longitudinally revealed general predicted activation (Z-score > 0) of CREB signaling in int1-2, inhibition (Z-score < 0) from int2-3 to int5-6, and further activation at int6-7 in the CIPN negative group. A similar activation-inhibition pattern was also observed for the opioid signaling pathway. Conclusions: Using our multi-omic approach, we observed that CIPN is associated with changes in CREB signaling and opioid signaling pathways, which may provide novel opportunities for therapeutic intervention and biomarker development. Funding: R61NS113258-01A1, R33NS113258 Citation Format: Anukriti Sharma, Ken B. Johnson, Alper Sen, Bihua Bie, Emily E. Rhoades, Courtney Hershberger, Mei Wei, N. Lynn Henry, Carla Bou Dargham, G. Thomas Budd, Joseph Foss, Daniel M. Rotroff. Longitudinal multi-omics study reveals potential targets against chemotherapy induced peripheral neuropathy during taxane treatment [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2024; 2024 Dec 10-13; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2025;31(12 Suppl):Abstract nr P1-04-02.
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Dr., V. Lakshminarayanan. "ENHANCEMENT THE PERFORMANCE OF 64cm2 INTERDIGITATED FLOW CHANNEL OF PEM FUEL CELL BY TAGUCHI METHOD." International Journal of Advanced Trends in Engineering and Technology 2, no. 2 (2017): 11–15. https://doi.org/10.5281/zenodo.834352.
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The Proton Exchange Membrane (PEM) fuel cell is an electrochemical device and its performance depends on the design and operating parameters. In this paper, optimization of various operating and design parameters on interdigitated flow channel with64cm<sup>2</sup>active area of the PEM fuel cell was considered. The modeling of Three Dimensional (3-D) PEM fuel cell, Analysis and optimization by Taguchi method was done by Creo Parametric 2.0, CFD Fluent 14.5and Minitab 17 software respectively. Based on the optimization study, the R: C- 1:2hasproduced 0.169 W/cm<sup>2</sup> of power density on PEM fuel cell performance and square of response factor (R<sup>2</sup>) was achieved by Taguchi method as 99.93%.
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Bhovi, Prabhakar M., Akash R. Naik, Dattatraya Adarsh, C. G. Ranjitkumar, and K. Venkateswarlu. "Simulation Studies and Evolution of Mechanical Properties of AA6061 Subjected to RCS." Advanced Materials Research 1148 (June 2018): 142–51. http://dx.doi.org/10.4028/www.scientific.net/amr.1148.142.
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AA6061 alloy was selected as starting material, as this alloy play vital role in aerospace, automotive and naval applications. To enhance mechanical properties and study the structural correlation of AA6061 using one of the promising SPD (Severe Plastic Deformation) technique. In RCS (Repetitive Corrugation and Straightening), repetitive bending and shearing stresses act alternatively on the specimen. The die models and work piece were designed using Creo parametric 2.0 and imported to AFDEX-2014 (Adviser metal Forming Design Expert) for simulation studies. AA6061 was subjected to four passes (8 stages) of RCS. Effective strain observed in AA6061 alloy was 2.389 and strain rate increased during corrugation and less during straightening stages. The theoretical effective strain was 2.65.The experimental effective strain was validated and found to be nearly approximately 92% of the theoretical result. Further, mechanical properties like tensile strength and microhardness increased to 1.5 to 2 times in AA6061 alloy after eight passes of RCS. Keywords: AA6061, RCS, SPD, Microhardness, Tensile strength
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Rihane, Salah Eddine, Mohand Ouamar Hernane, and Alain Togbé. "A parametric family of quartic Thue inequalities." Notes on Number Theory and Discrete Mathematics 27, no. 4 (2021): 1–14. http://dx.doi.org/10.7546/nntdm.2021.27.4.1-14.
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Let c\neq 0,-1 be an integer. In this paper, we use the method of Tzanakis to transform the quartic Thue equation x^4 -(c^2+c+4) x^3y +(c^2+c+3) x^2 y^2 +2 xy^3 -y^4 = \mu into systems of Pell equations. Then, we determine all primitive solutions (x,y) with 0<|\mu|\leq |c+1|.
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Kiranbabu, P., V. Sivaprasad, Raghuram Pradhan, L. Ramprasad Reddy, S. Kondala Rao, and Yarram Srinivasa Reddy. "Performance Analysis of The Hairpin Heat Exchanger Using Different Nano Fluids." International Journal of Innovative Research in Computer Science & Technology 10, no. 3 (2022): 386–92. http://dx.doi.org/10.55524/ijircst.2022.10.3.61.
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An apparatus that moves heat from one fluid to another is a heat exchanger. To avoid mixing, the fluids may be separated by a solid wall, or they may be in direct touchHairpin Exchangers are available in bare tubes, finned tubes, U-tubes, straight tubes (with rod-thru capability), fixed tube sheets, and detachable bundles. They also come in single tubes (Double Pipe) and numerous tubes within a hairpin shell (Multitude). The combination characteristics of nano fluid and base fluid water are calculated in this article. Magnesium Oxide and silver nano particle volume fractions of 0.35, 0.45, 0.55, and 0.65 percent at varied velocities (0.5, 1,1.5, and 2 m/s) were used as nano fluids. The properties of nanofluids are calculated theoretically, and the results are used as inputs for analysisA 3D model of the hair pin heat exchanger with and without twisted tape is made using CREO parametric software. CFD analysis of the hair pin heat exchanger is performed at different nanofluid volume fractions. The pressure drop, Reynolds number, heat transfer coefficient, and Nusselt number are all determined using CFD analysis.
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Carton, Xavier, Thomas Meunier, Glenn R. Flierl, Xavier Perrot, and Mikhail A. Sokolovskiy. "Explosive instability of geostrophic vortices. Part 2: parametric instability." Theoretical and Computational Fluid Dynamics 24, no. 1-4 (2009): 131–35. http://dx.doi.org/10.1007/s00162-009-0139-0.
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Ghosh, Debashis, and Lakshmi Kanta Dey. "On some parametric classifications of quasi-symmetric 2-designs." Tamkang Journal of Mathematics 46, no. 3 (2015): 269–80. http://dx.doi.org/10.5556/j.tkjm.46.2015.1755.
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Quasi-symmetric $2$-designs with block intersection numbers $x$ and $y$, where $y=x+4$ and $x > 0$ are considered. If $D(v, b, r, k, \lambda; x, y)$ is a quasi-symmetric $2$-design with above condition, then it is shown that the number of such designs is finite, whenever $3\leq x \leq 68$. Moreover, the non-existence of triangle free quasi-symmetric $2$-designs under these parameters is obtained.
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Nazin, S. S., and V. B. Shikin. "Parametric excitation of the charged surface of liquid helium." Soviet Journal of Low Temperature Physics 12, no. 2 (1986): 65–68. https://doi.org/10.1063/10.0031434.
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The instability of the charged surface of superfluid helium in a time-alternating normal electric field of the form E⊥=E⊥0+δE⊥cos2Ωt is investigated. The δE⊥ instability threshold for parametric resonance is calculated in the hydrodynamic approximation to within η3/2 (η is the first viscosity coefficient) in the first order with respect to δE⊥/E⊥0.Explicit relations obtained for δE⊥ as a function of E⊥0 by numerical calculations are given for the case T = 0.9 °K, ns = 108 cm−2 (ns is the surface density of electrons) at Ω = 100 and 400 Hz.
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Kats, Vladimir, and Eugene Levner. "Parametric algorithms for 2-cyclic robot scheduling with interval processing times." Journal of Scheduling 14, no. 3 (2010): 267–79. http://dx.doi.org/10.1007/s10951-010-0166-0.
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Bai, Yunru, Leszek Gasiński, and Nikolaos S. Papageorgiou. "Nonlinear Eigenvalue Problems for the Dirichlet (p,2)-Laplacian." Axioms 11, no. 2 (2022): 58. http://dx.doi.org/10.3390/axioms11020058.
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We consider a nonlinear eigenvalue problem driven by the Dirichlet (p,2)-Laplacian. The parametric reaction is a Carathéodory function which exhibits (p−1)-sublinear growth as x→+∞ and as x→0+. Using variational tools and truncation and comparison techniques, we prove a bifurcation-type theorem describing the “spectrum” as λ>0 varies. We also prove the existence of a smallest positive eigenfunction for every eigenvalue. Finally, we indicate how the result can be extended to (p,q)-equations (q≠2).
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Pane, Rahmawati, and Sutarman. "Estimation of Heteroskedasticity Semiparametric Regression Curve Using Fourier Series Approach." Journal of Research in Mathematics Trends and Technology 2, no. 1 (2020): 14–20. http://dx.doi.org/10.32734/jormtt.v2i1.3744.
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A heteroskedastic semiparametric regression model consists of two main components, i.e. parametric component and nonparametric component. The model assumes that any data (x̰ i′ , t i , y i ) follows y i = x̰ i′ β̰+ f(t i ) + σ i ε i , where i = 1,2, … , n , x̰ i′ = (1, x i1 , x i2 , … , x ir ) and t i is the predictor variable. Parameter vector β̰ = (β 1 , β 2 , … , β r ) ′ ∈ ℜ r is unknown and f(t i ) is also unknown and is assumed to be in interval of C[0,π] . Random error ε i is independent on zero mean and varianceσ 2 . Estimation of the heteroskedastic semiparametric regression model was conducted to evaluate the parametric and nonparametric components. The nonparametric component f(t i ) regression was approximated by Fourier series F(t) = bt + 12 α 0 + ∑ α k 𝑐 𝑜𝑠 kt Kk=1 . The estimation was obtained by means of Weighted Penalized Least Square (WPLS): min f∈C(0,π) {n −1 (y̰− Xβ̰−f̰) ′ W −1 (y̰− Xβ̰− f̰) + λ ∫ 2π [f ′′ (t)] 2 dt π0 } . The WPLS solution provided nonparametric component f̰̂ λ (t) = M(λ)y̰ ∗ for a matrix M(λ) and parametric component β̰̂ = [X ′ T(λ)X] −1 X ′ T(λ)y̰
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BARBU, LUMINIŢA, and GHEORGHE MOROŞANU. ""Eigenvalues of the (p, q, r)-Laplacian with a parametric boundary condition"." Carpathian Journal of Mathematics 38, no. 3 (2022): 547–61. http://dx.doi.org/10.37193/cjm.2022.03.03.
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"Consider in a bounded domain $\Omega \subset \mathbb{R}^N$, $N\ge 2$, with smooth boundary $\partial \Omega$ the following nonlinear eigenvalue problem \begin{equation*} \left\{\begin{array}{l} -\sum_{\alpha \in \{ p,q,r\}}\rho_{\alpha}\Delta_{\alpha}u=\lambda a(x) \mid u\mid ^{r-2}u\ \ \mbox{ in} ~ \Omega,\\[1mm] \big(\sum_{\alpha \in \{p,q,r\}}\rho_{\alpha}\mid \nabla u\mid ^{\alpha-2}\big)\frac{\partial u}{\partial\nu}=\lambda b(x) \mid u\mid ^{r-2}u ~ \mbox{ on} ~ \partial \Omega, \end{array}\right. \end{equation*} where $p, q, r\in (1, +\infty),~q<p,~r\not\in \{p, q\};$ $\rho_p, \rho_q, \rho_r$ are positive constants; $\Delta_{\alpha}$ is the usual $\alpha$-Laplacian, i.e., $\Delta_\alpha u=\, \mbox{div} \, (|\nabla u|^{\alpha-2}\nabla u)$; $\nu$ is the unit outward normal to $\partial \Omega$; $a\in L^{\infty}(\Omega),$ $b\in L^{\infty}(\partial\Omega)$ {are given nonnegative functions satisfying} $\int_\Omega a~dx+\int_{\partial\Omega} b~d\sigma >0.$ Such a triple-phase problem is motivated by some models arising in mathematical physics. If $r \not\in (q, p),$ we determine a positive number $\lambda_r$ such that the set of eigenvalues of the above problem is precisely $\{ 0\} \cup (\lambda_r, +\infty )$. On the other hand, in the complementary case $r \in (q, p)$ with $r < q(N-1)/(N-q)$ if $q<N$, we prove that there exist two positive constants $\lambda_*<\lambda^*$ such that any $\lambda\in \{0\}\cup [\lambda^*, \infty)$ is an eigenvalue of the above problem, while the set $(-\infty, 0)\cup (0, \lambda_*)$ contains no eigenvalue $\lambda$ of the problem."
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Ali, Mohammed, and Hussain Al-Qassem. "On Rough Parametric Marcinkiewicz Integrals Along Certain Surfaces." Mathematics 13, no. 8 (2025): 1287. https://doi.org/10.3390/math13081287.
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In this paper, we study rough Marcinkiewicz integrals associated with surfaces defined by ΨP,ϕ={(˜P(w),ϕ(w)):w∈Rm}. We establish the Lp-boundedness of these integrals when the kernel functions lie in the Lq(Sm−1) space. Combining this result with Yano’s extrapolation technique, we further obtain the Lp-boundedness under weaker kernel conditions—specifically, when the kernels belong to either the block space Bq(0,−1/2)(Sm−1) or L(logL)1/2(Sm−1). Our results extend and refine several previously known results on Marcinkiewicz integrals, offering broader applicability and sharper conclusions.
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Téllez-Velázquez, Arturo, Herón Molina-Lozano, Luis A. Villa-Vargas, et al. "A Feasible Genetic Optimization Strategy for Parametric Interval Type-2 Fuzzy Logic Systems." International Journal of Fuzzy Systems 20, no. 1 (2017): 318–38. http://dx.doi.org/10.1007/s40815-017-0307-0.
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Nath, C. Nageswara, M. Tajuddin, and JM Kumar. "On the parametric model of loose bonding between poroelastic half-spaces." Journal of Vibration and Control 18, no. 9 (2011): 1261–74. http://dx.doi.org/10.1177/1077546311417834.
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Wave propagation in a Newtonian viscous liquid layer of thickness ‘ h’ and of shear viscosity ‘ η’ bounded by two poroelastic half-spaces is studied. Possible bonding between the poroelastic half-spaces is discussed by considering the limiting forms of the secular equation, when h→0: (1) η is finite or η→0 such that η/h → ∞, (2) η→0 such that η/h → 0, (3) η → 0 such that η/h is a finite nonzero quantity, for each permeable and impermeable surface. It is shown that these three forms respectively represent welded, smooth and loosely bonded interface of poroelastic half-spaces. The secular equation for the interfacial waves for each of the above three types of bonding for infinite wavelength is derived as a particular case. It is observed that this secular equation is the same for all three types of bonding for each permeable and impermeable surface. Several other special cases are obtained.
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Yang, Jie, Haibo Chen, and Senli Liu. "Multiplicity of Nodal Solutions for a Class of Double-Phase Problems." Journal of Function Spaces 2020 (June 4, 2020): 1–7. http://dx.doi.org/10.1155/2020/3805803.
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We consider the following parametric double-phase problem: −div∇up−2∇u+ax∇uq−2∇u=λfx,u in Ω,u=0,on ∂Ω.. We do not impose any global growth conditions to the nonlinearity fx,u, which refer solely to its behavior in a neighborhood of u=0. And we will show that they suffice for the multiplicity of signed and nodal solutions of the double-phase problem above when λ is large enough.
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Xingbo, Liu. "Dynamics Near the Heterodimensional Cycles with Nonhyperbolic Equilibrium." International Journal of Bifurcation and Chaos 28, no. 01 (2018): 1850003. http://dx.doi.org/10.1142/s0218127418500037.
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In this paper, bifurcations of heterodimensional cycle with one nonhyperbolic equilibrium and one saddle-focus in three-dimensional vector fields are investigated. We study the interaction of a transcritical bifurcation with a codimension-0/codimension-2 heteroclinic cycle. Based on the construction of a Poincaré return map, we obtain the expressions of parametric curves of homoclinic and heteroclinic connections around the heterodimensional cycle as well as periodic orbits. Furthermore, the configurations of the parametric curves corresponding to different bifurcations are illustrated.
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Alvarez-Caudevilla, Pablo, Cristina Brandle, and Devashish Sonowal. "Positive solutions for n-dimensional fourth-order systems under a parametric condition." Electronic Journal of Differential Equations 2025, no. 01-?? (2025): 56. https://doi.org/10.58997/ejde.2025.56.
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We establish the existence of positive solutions for a system of coupled fourth-order partial differential equations on a bounded domain \(\Omega \subset \mathbb{R}^n\), $$\displaylines{ \Delta^2u_1 +\beta_1 \Delta u_1-\alpha_1 u_1=f_1({ x},u_1,u_2),\cr \Delta^2 u_2+\beta_2\Delta u_2-\alpha_2 u_2=f_2({ x},u_1,u_2), }$$ for \(x\in\Omega\), subject to homogeneous Navier boundary conditions, where the functions \(f_1,f_2 : \Omega\times [0,\infty)\times [0,\infty) \to [0,\infty)\) are continuous, and \(\alpha_1,\alpha_2,\beta_1\) and \(\beta_2\) are real parameters satisfying certain constraints related to the eigenvalues of the associated Laplace operator. For more information see https://ejde.math.txstate.edu/Volumes/2025/56/abstr.html
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Alemayehu, Dawit Bogale, Masahiro Todoh, and Song-Jeng Huang. "Advancing 3D Dental Implant Finite Element Analysis: Incorporating Biomimetic Trabecular Bone with Varied Pore Sizes in Voronoi Lattices." Journal of Functional Biomaterials 15, no. 4 (2024): 94. http://dx.doi.org/10.3390/jfb15040094.
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The human mandible’s cancellous bone, which is characterized by its unique porosity and directional sensitivity to external forces, is crucial for sustaining biting stress. Traditional computer- aided design (CAD) models fail to fully represent the bone’s anisotropic structure and thus depend on simple isotropic assumptions. For our research, we use the latest versions of nTOP 4.17.3 and Creo Parametric 8.0 software to make biomimetic Voronoi lattice models that accurately reflect the complex geometry and mechanical properties of trabecular bone. The porosity of human cancellous bone is accurately modeled in this work using biomimetic Voronoi lattice models. The porosities range from 70% to 95%, which can be achieved by changing the pore sizes to 1.0 mm, 1.5 mm, 2.0 mm, and 2.5 mm. Finite element analysis (FEA) was used to examine the displacements, stresses, and strains acting on dental implants with a buttress thread, abutment, retaining screw, and biting load surface. The results show that the Voronoi model accurately depicts the complex anatomy of the trabecular bone in the human jaw, compared to standard solid block models. The ideal pore size for biomimetic Voronoi lattice trabecular bone models is 2 mm, taking in to account both the von Mises stress distribution over the dental implant, screw retention, cortical bone, cancellous bone, and micromotions. This pore size displayed balanced performance by successfully matching natural bone’s mechanical characteristics. Advanced FEA improves the biomechanical understanding of how bones and implants interact by creating more accurate models of biological problems and dynamic loading situations. This makes biomechanical engineering better.
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Perumal, A. K., and Y. Zhou. "Parametric study and scaling of jet manipulation using an unsteady minijet." Journal of Fluid Mechanics 848 (June 8, 2018): 592–630. http://dx.doi.org/10.1017/jfm.2018.376.
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A parametric study is conducted for the control of a turbulent jet using a single unsteady minijet. A number of control parameters that influence the decay rate $K$ of the jet centreline mean velocity are investigated, including the mass flow rate ratio $C_{m}$, excitation frequency ratio $f_{e}/f_{0}$ and exit diameter ratio $d/D$ of the minijet to main jet, along with the duty cycle ($\unicode[STIX]{x1D6FC}$) of the minijet injection. Extensive hot-wire, particle image velocimetry and flow visualization measurements were performed in the manipulated jet. Various flow structures have been identified, such as the flapping flow, non-flapping flow and that showing a manipulable thrust vector, depending on $C_{m}$, $f_{e}/f_{0}$ and $\unicode[STIX]{x1D6FC}$. Empirical scaling analysis unveils that, prior to the minijet impingement upon the wall of the nozzle and the generation of turbulence, the relationship $K=g_{1}$ ($C_{m}$, $f_{e}/f_{0}$, $d/D$, $\unicode[STIX]{x1D6FC}$) may be reduced to $K=g_{2}$ ($\unicode[STIX]{x1D709}$), where $g_{1}$ and $g_{2}$ are different functions and the scaling factor $\unicode[STIX]{x1D709}=(\sqrt{MR}/\unicode[STIX]{x1D6FC})(d/D)^{n}$ ($\sqrt{MR}\equiv C_{m}(D/d)$ is the momentum ratio and $n$ is a constant that depends on $\unicode[STIX]{x1D6FC}$) is physically the effective momentum ratio per pulse or effective penetration depth. Discussion is conducted based on $K=g_{2}$ ($\unicode[STIX]{x1D709}$), which provides important insight into the jet control physics.
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Li, Shengfeng, and Yi Dong. "Parametric Estimation in the Vasicek-Type Model Driven by Sub-Fractional Brownian Motion." Algorithms 11, no. 12 (2018): 197. http://dx.doi.org/10.3390/a11120197.
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In the paper, we tackle the least squares estimators of the Vasicek-type model driven by sub-fractional Brownian motion: d X t = ( μ + θ X t ) d t + d S t H , t ≥ 0 with X 0 = 0 , where S H is a sub-fractional Brownian motion whose Hurst index H is greater than 1 2 , and μ ∈ R , θ ∈ R + are two unknown parameters. Based on the so-called continuous observations, we suggest the least square estimators of μ and θ and discuss the consistency and asymptotic distributions of the two estimators.
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Gu, Ruijie, Jiameng Gao, Shuaifeng Zhao, and Hao Xing. "Research and Mechanism Design Analysis of Leg Lifting Device Based on Human Body Stretching." Machines 13, no. 2 (2025): 78. https://doi.org/10.3390/machines13020078.
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Leg stretching devices are one of the main instruments used to improve human function. To solve the limitations of existing leg stretching products, such as single function and low degree of coincidence, a leg stretching device satisfying ergonomics was studied in this paper. Firstly, the Box–Behnken Design (BBD) response surface methodology was applied to establish a regression model for leg force. Secondly, a motion analysis was conducted on the leg lifting mechanism using analytical methods, and the model data were coupled by Creo Parametric and Automatic Dynamic Analysis of Mechanical System (ADAMS) 2019 software to develop the kinematic model. Then, the motion characteristics during the whole process were studied, and the motion parameter curves were obtained. Next, ABAQUS 2022 software was employed to create the finite element simulation model of the leg lifting device, and key component strength was also analyzed. Finally, a prototype of the device was made and experimentally validated with leg lifting. The results show that in the case of different heights and weights, the lifting angle of the human leg has a significant effect on the force state during the leg lifting process. When the leg is lifted 0–30°, the force on the leg is small. As the leg lifting angle increases, the force on the leg also increases. In the process of leg lifting, the angular velocity and angular acceleration of the leg lifting mechanism change more gently, and there is no obvious mutation. The maximum stress of the driving rod is 102.5 MPa, the maximum stress of the lifting rod is 88.12 MPa, and the maximum stress of the leg placing plate is 40.5 MPa, all of which meet the strength requirements and provide a reference for the research of the human leg stretching device.
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Nasiruzzaman, Md, Nadeem Rao, Manish Kumar, and Ravi Kumar. "Approximation on bivariate parametric-extension of Baskakov-Durrmeyer-operators." Filomat 35, no. 8 (2021): 2783–800. http://dx.doi.org/10.2298/fil2108783n.
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The main purpose of this article is to study the bivariate approximation generalization for Baskakov-Durrmeyer-operators with the aid of non-negative parametric variants suppose 0 ? ?1,?2 ? 1. We obtain the order of approximation by use of the modulus of continuity in terms of well known Peetre?s K-functional, Voronovskaja type theorems and Lipschitz maximal functions. Further, we also discuss here the approximation properties of the operators in B?gel-spaces by use of mixed-modulus of continuity.
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Belikova, M. Ya, T. N. Trofimova, M. Yu Kabanov, and K. V. Sementsov. "MR-ELASTOGRAPHY OF THE PANCREAS: RESEARCH TECHNIQUE, NORMAL VALUES, FIRST RESULTS OF APPLICATION IN PATIENTS WITH PANCREATIC ADENOCARCINOMA AT THE PLANNING OF PANCREATODUODENODAL RESECTION." Diagnostic radiology and radiotherapy, no. 2 (August 4, 2019): 80–84. http://dx.doi.org/10.22328/2079-5343-2019-10-2-80-84.
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Objective: optimization of the technique and study of the possibilities of MR-elastography in assessing the rigidity of the pancreatic parenchyma under normal conditions, with fibrotic changes and adenocarcinoma. Materials and methods. MR elastography was performed for 15 patients with no history and clinical laboratory data indicating the presence of pancreatic diseases, 20 patients with pancreatic adenocarcinoma at the stage of preoperative planning to assess the rigidity of the tumor and parenchyma, in order to predict the probability of pancreatic fistulas. With the application of special software, the quantitative values of stiffness in kPa were calculated, a qualitative analysis of the state of the parenchyma was carried out using color parametric maps. Results. The stiffness of the pancreatic parenchyma normally ranged from 1,54 to 2,87 kPa, averaging 2,5 kPa. The unchanged parenchyma was characterized by blue staining on color parametric maps in the hardness range from 0 to 8 kPa, violet in the range from 0 to 20 kPa. In patients with a tumor process in all cases there was a low-grade adenocarcinoma of the pancreatic head, verified by histological data. The rigidity of adenocarcinoma varied from 6 to 9 kPa, on the color parametric maps there was a red staining of the tumor in the range of hardness of 0– 8 kPa, yellow in the range of 0–20 kPa. In the postoperative period, the pancreatic fistula on the background of preoperative preparation was formed only in 3 patients with normal pancreatic parenchyma, according to elastography rigidity indicators. Conclusion. MR-elastography is an informative method for quantitative and qualitative analysis of the stiffness of pancreatic parenchyma, and effective instrument for predicting the development of pancreatic fistulas.
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Petrov, V., A. Yelisseyev, L. Isaenko, S. Lobanov, A. Titov, and J. J. Zondy. "Second harmonic generation and optical parametric amplification in the mid-IR with orthorhombic biaxial crystals LiGaS 2 and LiGaSe 2." Applied Physics B: Lasers and Optics 78, no. 5 (2004): 543–46. http://dx.doi.org/10.1007/s00340-004-1463-0.
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Pal, Satyabrata, and Kalyan Kumar Goswami. "A New Class of Latin Square Type PBIB Designs." Calcutta Statistical Association Bulletin 42, no. 1-2 (1992): 135–42. http://dx.doi.org/10.1177/0008068319920113.
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A method of construction of a new class of Latin square association scheme with i=2 constraints ( L2 design) has been obtained. The method eventually yields a solution of an unsolved L2 (6) design whose parametric combinations are v=36, b=60, r= 10, K=6, λ1 =0 and λ2 =2. This method of construction also implies the existence of a new series of orthogonal array.
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Høibakk, Ralph, Dag Lukkassen, Annette Meidell, and Lars-Erik Persson. "A New Look at the Single Ladder Problem (SLP) via Integer Parametric Solutions to the Corresponding Quartic Equation." Mathematics 8, no. 2 (2020): 267. http://dx.doi.org/10.3390/math8020267.
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The aim is to put new light on the single ladder problem (SLP). Some new methods for finding complete integer solutions to the corresponding quartic equation z 4 − 2 L z 3 + ( L 2 − a 2 − b 2 ) z 2 + 2 L a 2 z − L 2 a 2 = 0 are developed. For the case L ≥ L min , these methods imply a complete parametric representation for integer solutions of SLP in the first quadrant. Some corresponding (less complete) results for the case L > L min are also pointed out.
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Mosleh, Moein, Rik J. Williams, and Marijn Franx. "ON THE ROBUSTNESS OFz= 0-1 GALAXY SIZE MEASUREMENTS THROUGH MODEL AND NON-PARAMETRIC FITS." Astrophysical Journal 777, no. 2 (2013): 117. http://dx.doi.org/10.1088/0004-637x/777/2/117.
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Ali, Mohammed, and Oqlah Al-Refai. "Boundedness of Generalized Parametric Marcinkiewicz Integrals Associated to Surfaces." Mathematics 7, no. 10 (2019): 886. http://dx.doi.org/10.3390/math7100886.
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In this article, the boundedness of the generalized parametric Marcinkiewicz integral operators M Ω , ϕ , h , ρ ( r ) is considered. Under the condition that Ω is a function in L q ( S n - 1 ) with q ∈ ( 1 , 2 ] , appropriate estimates of the aforementioned operators from Triebel–Lizorkin spaces to L p spaces are obtained. By these estimates and an extrapolation argument, we establish the boundedness of such operators when the kernel function Ω belongs to the block space B q 0 , ν - 1 ( S n - 1 ) or in the space L ( l o g L ) ν ( S n - 1 ) . Our results represent improvements and extensions of some known results in generalized parametric Marcinkiewicz integrals.
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Lestari, Susi, Ace Baehaki, and Imam Mahdi Rahmatullah. "Pengaruh Kondisi Post Mortem Ikan Patin (Pangasius Djambal) dengan Kematian Menggelepar yang Disimpan pada Suhu Berbeda Terhadap Mutu Filletnya." Jurnal FishtecH 9, no. 1 (2020): 34–44. http://dx.doi.org/10.36706/fishtech.v9i1.11005.
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This study aimed to determine the quality of differences in catfish fillets made in the pre rigor, rigor mortis, and post rigorstage. This research is divided into 2 stages, the preliminary research stage and further research. Data processing is carried out quantitatively by analyzing parametric statistical data with Anova and non parametric tests with the Kruskal Wallis test. The parameters of this study include stiffness index, pH value, TVB and organoleptic test. Preliminary research results on catfish at the meeting room temperature pre rigor, rigor mortis, and post rigor are interrelated at 0, 1.5, 9 hours with rigor index values of 0%, 27%, 5% and time of pre rigor and rigor mortis at cold temperatures at 0 and 6 hours with rigor index values of 0% and 70%.. In the main study it was shown that all TVB comparisons are significantly different and at pH values all are significantly different except for cold temperature pre rigor and post rigor comparisons. The results of organoleptic fillets showed significantly different results in the comparison of rigor mortis and post rigor phases in the part of testing the appearance of meat integrity and color appearance of filllet meat at cold temperatures.
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Henriksson, M., L. Sjöqvist, V. Pasiskevicius та F. Laurell. "Narrow linewidth 2 μm optical parametric oscillation in periodically poled LiNbO3 with volume Bragg grating outcoupler". Applied Physics B 86, № 3 (2006): 497–501. http://dx.doi.org/10.1007/s00340-006-2446-0.
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Shaw, James D., and James Guyker. "On Parametric and Matrix Solutions to the Diophantine Equation x 2 + d y 2 − z 2 = 0 Where d Is a Positive Square‐Free Integer." International Journal of Mathematics and Mathematical Sciences 2023 (September 25, 2023): 1–18. http://dx.doi.org/10.1155/2023/1505337.
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The well‐known matrix‐generated tree structure for Pythagorean triplets is extended to the primitive solutions of the Diophantine equation x 2 + d y 2 − z 2 = 0 where d is a positive square‐free integer. The proof is based on a parametrization of these solutions as well as on a dual version of the Fermat’s method of descent.
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Dmitriy, Demin. "CONSTRUCTING THE PARAMETRIC FAILURE FUNCTION OF THE TEMPERATURE CONTROL SYSTEM OF INDUCTION CRUCIBLE FURNACES." EUREKA: Physics and Engineering, no. 6 (November 30, 2020): 19–32. https://doi.org/10.21303/2461-4262.2020.001489.
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The objects of the study were diagnostic features that allow determining the quality of controlling temperature modes of induction crucible melting. For this, in the normalized space of feature factors, which are the content of SiO<sub>2</sub> and FeO+Fe<sub>2</sub>O<sub>3 </sub>in slag, a discriminant function is constructed and a decision rule is obtained in the form of a linear classifier, which allows determining in which mode the process was carried out. It is shown that this rule is the basis for identifying an event qualified as a parametric failure, and it can be included in the general structure of the parametric failure function. The parametric failure function constructed for the temperature control system of induction crucible melting makes it possible to ascertain that the control system does not meet the specified requirements for a specific temperature mode of melting. The mechanism of inferencing regarding the occurrence of a parametric failure based on this function is as follows. If the decision rule showed that the object belongs to the “low-temperature mode” class, although the process under these conditions should have been carried out in the high-temperature mode, a parametric failure is recorded. In this case, the numerical value of this function takes the value of “1”, otherwise – “0”. The inferencing mechanism works similarly if, on the basis of the decision rule, it is revealed that the process was carried out in the high-temperature mode, although under these conditions it should have been carried out in the low-temperature mode. Based on the constructed parametric failure function, practical problems related to planning maintenance of the temperature control system integrated into the melting complex or organizational and technical measures aimed at minimizing violations of the melting regulations can be solved
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Anwar, Y. R., H. Tasman, and N. Hariadi. "Determining implicit equation of conic section from quadratic rational Bézier curve using Gröbner basis." Journal of Physics: Conference Series 2106, no. 1 (2021): 012017. http://dx.doi.org/10.1088/1742-6596/2106/1/012017.
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Abstract The Gröbner Basis is a subset of finite generating polynomials in the ideal of the polynomial ring k[x 1,…,xn ]. The Gröbner basis has a wide range of applications in various areas of mathematics, including determining implicit polynomial equations. The quadratic rational Bézier curve is a rational parametric curve that is generated by three control points P 0(x 0,y 0), P 1(xi ,yi ), P 2(x 2,y 2) in ℝ2 and weights ω 0, ω 1, ω 2, where the weights ω i are corresponding to control points Pi (xi, yi ), for i = 0,1, 2. According to Cox et al (2007), the quadratic rational Bézier curve can represent conic sections, such as parabola, hyperbola, ellipse, and circle, by defining the weights ω 0 = ω 2 = 1 and ω 1 = ω for any control points P 0(x 0, y 0), P 1(x 1, y 1), and P 2(x 2, y 2). This research is aimed to obtain an implicit polynomial equation of the quadratic rational Bézier curve using the Gröbner basis. The polynomial coefficients of the conic section can be expressed in the term of control points P 0(x 0, y 0), P 1(x 1, y 1), P 2(x 2, y 2) and weight ω, using Wolfram Mathematica. This research also analyzes the effect of changes in weight ω on the shape of the conic section. It shows that parabola, hyperbola, and ellipse can be formed by defining ω = 1, ω > 1, and 0 < ω < 1, respectively.
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Homaee, Mehdi, and Ahmad Farrokhian Firouzi. "Deriving point and parametric pedotransfer functions of some gypsiferous soils." Soil Research 46, no. 3 (2008): 219. http://dx.doi.org/10.1071/sr07161.
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Parametric description of the soil water retention curve as well as the hydraulic conductivity curve is needed for modelling water movement and solute transport in the vadose zone. The objective of this study was to derive pedotransfer functions (PTFs) to predict the water retention curve and the van Genuchten and the van Genuchten–Mualem parameters of some gypsiferous soils. Consequently, 185 gypsiferous soil samples were collected and their physical properties were measured. The particle size distribution was determined in 2 steps: (i) with gypsum, by covering the particles with barium sulphate; (ii) without gypsum, using the hydrometry method. The easily obtainable variables were grouped as (1) particle size distribution, bulk density, and gypsum content; and (2) bulk density, gypsum content, geometric mean, and geometric standard deviation of the particle diameter. Stepwise multiple linear regression method was used to derive the PTFs. Two types of parametric and point functions were derived using these variables. The first group of variables predicted water retention and the van Genuchten and van Genuchten–Mualem parameters better than the second group. The gypsum content appeared to be the second dominant parameter for predicting water retention at 0, −330, −1000, −3000, −5000, and −15 000 cm. The derived PTFs were compared with the Rosetta database as independent dataset. The validity test indicated that in order to predict the hydraulic properties of gypsiferous soils the derived PTFs are more accurate than what can be obtained from the Rosetta database. Removal of gypsum increased the water retention at pressure heads of 0, –100, –330, –1000, –3000, –5000, and –15 000 cm (P < 0.01). The results also indicated that hydraulic parameters were different for the same soil with and without gypsum.
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Skene, Calum S., and Peter J. Schmid. "Adjoint-based parametric sensitivity analysis for swirling M-flames." Journal of Fluid Mechanics 859 (November 21, 2018): 516–42. http://dx.doi.org/10.1017/jfm.2018.793.
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A linear numerical study is conducted to quantify the effect of swirl on the response behaviour of premixed lean flames to general harmonic excitation in the inlet, upstream of combustion. This study considers axisymmetric M-flames and is based on the linearised compressible Navier–Stokes equations augmented by a simple one-step irreversible chemical reaction. Optimal frequency response gains for both axisymmetric and non-axisymmetric perturbations are computed via a direct–adjoint methodology and singular value decompositions. The high-dimensional parameter space, containing perturbation and base-flow parameters, is explored by taking advantage of generic sensitivity information gained from the adjoint solutions. This information is then tailored to specific parametric sensitivities by first-order perturbation expansions of the singular triplets about the respective parameters. Valuable flow information, at a negligible computational cost, is gained by simple weighted scalar products between direct and adjoint solutions. We find that for non-swirling flows, a mode with azimuthal wavenumber $m=2$ is the most efficiently driven structure. The structural mechanism underlying the optimal gains is shown to be the Orr mechanism for $m=0$ and a blend of Orr and other mechanisms, such as lift-up, for other azimuthal wavenumbers. Further to this, velocity and pressure perturbations are shown to make up the optimal input and output showing that the thermoacoustic mechanism is crucial in large energy amplifications. For $m=0$ these velocity perturbations are mainly longitudinal, but for higher wavenumbers azimuthal velocity fluctuations become prominent, especially in the non-swirling case. Sensitivity analyses are carried out with respect to the Mach number, Reynolds number and swirl number, and the accuracy of parametric gradients of the frequency response curve is assessed. The sensitivity analysis reveals that increases in Reynolds and Mach numbers yield higher gains, through a decrease in temperature diffusion. A rise in mean-flow swirl is shown to diminish the gain, with increased damping for higher azimuthal wavenumbers. This leads to a reordering of the most effectively amplified mode, with the axisymmetric ($m=0$) mode becoming the dominant structure at moderate swirl numbers.
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Repovš, Dušan D., and Calogero Vetro. "The behavior of solutions of a parametric weighted $ (p, q) $-Laplacian equation." AIMS Mathematics 7, no. 1 (2021): 499–517. http://dx.doi.org/10.3934/math.2022032.
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<abstract><p>We study the behavior of solutions for the parametric equation</p> <p><disp-formula> <label/> <tex-math id="FE1"> \begin{document}$ -\Delta_{p}^{a_1} u(z)-\Delta_{q}^{a_2} u(z) = \lambda |u(z)|^{q-2} u(z)+f(z,u(z)) \quad \mbox{in } \Omega,\, \lambda &gt;0, $\end{document} </tex-math></disp-formula></p> <p>under Dirichlet condition, where $ \Omega \subseteq \mathbb{R}^N $ is a bounded domain with a $ C^2 $-boundary $ \partial \Omega $, $ a_1, a_2 \in L^\infty(\Omega) $ with $ a_1(z), a_2(z) &gt; 0 $ for a.a. $ z \in \Omega $, $ p, q \in (1, \infty) $ and $ \Delta_{p}^{a_1}, \Delta_{q}^{a_2} $ are weighted versions of $ p $-Laplacian and $ q $-Laplacian. We prove existence and nonexistence of nontrivial solutions, when $ f(z, x) $ asymptotically as $ x \to \pm \infty $ can be resonant. In the studied cases, we adopt a variational approach and use truncation and comparison techniques. When $ \lambda $ is large, we establish the existence of at least three nontrivial smooth solutions with sign information and ordered. Moreover, the critical parameter value is determined in terms of the spectrum of one of the differential operators.</p></abstract>
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Lee, Ji-Eun. "Slant Curves in Contact Lorentzian Manifolds with CR Structures." Mathematics 8, no. 1 (2020): 46. http://dx.doi.org/10.3390/math8010046.
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In this paper, we first find the properties of the generalized Tanaka–Webster connection in a contact Lorentzian manifold. Next, we find that a necessary and sufficient condition for the ∇ ^ -geodesic is a magnetic curve (for ∇) along slant curves. Finally, we prove that when c ≤ 0 , there does not exist a non-geodesic slant Frenet curve satisfying the ∇ ^ -Jacobi equations for the ∇ ^ -geodesic vector fields in M. Thus, we construct the explicit parametric equations of pseudo-Hermitian pseudo-helices in Lorentzian space forms M 1 3 ( H ^ ) for H ^ = 2 c > 0 .
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CHANG, SHU-MING, WEN-WEI LIN, and TAI-CHIA LIN. "CHAOTIC AND QUASIPERIODIC MOTIONS OF THREE PLANAR CHARGED PARTICLES." International Journal of Bifurcation and Chaos 11, no. 07 (2001): 1937–51. http://dx.doi.org/10.1142/s0218127401003127.
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We study two dynamical systems for the motion of three planar charged particles with charges nj ∈ {±1}, j = 1, 2, 3. Both dynamical systems are parametric with a parameter α ∈ [0, 1] and have the same nonlinear terms. As α = 0, 1, the dynamical systems have no chaos. However, one dynamical system may create chaos as α varies from zero to one. This may provide an example to show that the homotopy deformation of dynamical systems cannot preserve the long-time dynamics even though the dynamical systems have the same nonlinear terms.
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HOANG, V. H., and CH SCHWAB. "ANALYTIC REGULARITY AND POLYNOMIAL APPROXIMATION OF STOCHASTIC, PARAMETRIC ELLIPTIC MULTISCALE PDEs." Analysis and Applications 11, no. 01 (2013): 1350001. http://dx.doi.org/10.1142/s0219530513500012.
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A class of second order, elliptic PDEs in divergence form with stochastic and anisotropic conductivity coefficients and n known, separated microscopic length scales εi, i = 1, …, n in a bounded domain D ⊂ ℝd is considered. Neither stationarity nor ergodicity of these coefficients is assumed. Sufficient conditions are given for the random solution to converge ℙ-a.s, as εi → 0, to a stochastic, elliptic one-scale limit problem in a tensorized domain of dimension (n + 1)d. It is shown that this stochastic limit problem admits best N-term "polynomial chaos" type approximations which converge at a rate σ > 0 that is determined by the summability of the random inputs' Karhúnen–Loève expansion. The convergence of the polynomial chaos expansion is shown to hold ℙ-a.s. and uniformly with respect to the scale parameters εi. Regularity results for the stochastic, one-scale limiting problem are established. An error bound for the approximation of the random solution at finite, positive values of the scale parameters εi is established in the case of two scales, and in the case of n > 2, scales convergence is shown, albeit without giving a convergence rate in this case.
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Gasiński, Leszek, and Nikolaos S. Papageorgiou. "Multiple Solutions for Nonlinear Dirichlet Problems with Concave Terms." MATHEMATICA SCANDINAVICA 113, no. 2 (2013): 206. http://dx.doi.org/10.7146/math.scand.a-15570.
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We consider a nonlinear parametric Dirichlet problem with parameter $\lambda>0$, driven by the $p$-Laplacian and with a concave term $\lambda|u|^{q-2}u$, $1<q<p$ and a Carathéodory perturbation $f(z,\zeta)$ which is asymptotically $(p-1)$-linear at infinity. Using variational methods combined with Morse theory and truncation techniques, we show that there is a critical value $\lambda^*>0$ of the parameter such that for $\lambda\in (0,\lambda^*)$ the problem has five nontrivial smooth solutions, four of constant sign (two positive and two negative) and the fifth nodal. In the semilinear case ($p=2$), we show that there is a sixth nontrivial smooth solution, but we cannot provide information about its sign. Finally for the critical case $\lambda=\lambda^*$, we show that the nonlinear problem ($p\ne 2$) still has two nontrivial constant sign smooth solutions and the semilinear problem ($p=2$) has three nontrivial smooth solutions, two of which have constant sign.
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Bachmayr, Markus, Albert Cohen, and Giovanni Migliorati. "Sparse polynomial approximation of parametric elliptic PDEs. Part I: affine coefficients." ESAIM: Mathematical Modelling and Numerical Analysis 51, no. 1 (2016): 321–39. http://dx.doi.org/10.1051/m2an/2016045.
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We consider the linear elliptic equation − div(a∇u) = f on some bounded domain D, where a has the affine form a = a(y) = ā + ∑j≥1yjψj for some parameter vector y = (yj)j ≥ 1 ∈ U = [−1,1]N. We study the summability properties of polynomial expansions of the solution map y → u(y) ∈ V := H01(D) . We consider both Taylor series and Legendre series. Previous results [A. Cohen, R. DeVore and C. Schwab, Anal. Appl. 9 (2011) 11–47] show that, under a uniform ellipticity assuption, for any 0 <p< 1, the ℓp summability of the (∥ψj∥L∞)j ≥ 1 implies the ℓp summability of the V-norms of the Taylor or Legendre coefficients. Such results ensure convergence rates n− s of polynomial approximations obtained by best n-term truncation of such series, with s = (1/p)−1 in L∞(U,V) or s = (1/p)−(1/2) in L2(U,V). In this paper we considerably improve these results by providing sufficient conditions of ℓp summability of the coefficient V-norm sequences expressed in terms of the pointwise summability properties of the (|ψj|)j ≥ 1. The approach in the present paper strongly differs from that of [A. Cohen, R. DeVore and C. Schwab, Anal. Appl. 9 (2011) 11–47], which is based on individual estimates of the coefficient norms obtained by the Cauchy formula applied to a holomorphic extension of the solution map. Here, we use weighted summability estimates, obtained by real-variable arguments. While the obtained results imply those of [7] as a particular case, they lead to a refined analysis which takes into account the amount of overlap between the supports of the ψj. For instance, in the case of disjoint supports, these results imply that for all 0 <p< 2, the ℓp summability of the coefficient V-norm sequences follows from the weaker assumption that (∥ψj∥L∞)j ≥ 1 is ℓq summable for q = q(p) := 2p/(2−p) . We provide a simple analytic example showing that this result is in general optimal and illustrate our findings by numerical experiments. The analysis in the present paper applies to other types of linear PDEs with similar affine parametrization of the coefficients, and to more general Jacobi polynomial expansions.
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Lima, Leonardo R. de, Heloisa M. F. Mendes, Frederico M. Soriani, et al. "Histologic and inflammatory lamellar changes in horses with oligofructose-induced laminitis treated with a CXCR1/2 antagonist." Pesquisa Veterinária Brasileira 36, no. 1 (2016): 13–18. http://dx.doi.org/10.1590/s0100-736x2016000100002.
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Abstract: With the hypothesis that blocking chemokine signaling can ameliorate acute laminitis, the aim was to evaluate the therapeutic effect of intravenous DF1681B, a selective antagonist for CXCR1 and CXCR2 (chemokine receptors), in an oligofructose equine laminitis model. To twelve mixed breed clinically healthy hoses with no previous history of hoof-related lameness was administered oligofructose (10g/kg given by nasogastric tube) and divided into two groups: treated (intravenous DF1681B at 30mg/kg 6, 12, 18, and 24h after oligofructose) and non-treated groups. Laminar biopsies were performed before and 12, 36, and 72h after administering oligofructose. Samples were stained with periodic acid-Schiff (PAS) and scored from 0 to 6 according to epidermal cell and basal membrane changes. The IL-1β, IL-6, and CXCL1 RNA expressions were determined by RT-PCR. Parametric and non-parametric tests were used to compare times within each group (P<0.05). The PAS grades and IL-1β and IL-6 RNA expression increased in the non-treated group, but remained constant in the treated horses. In conclusion, DF1681B therapy reduced laminar inflammation and epidermal deterioration in treated horses. CXCR1/2 blockage should be considered therapeutically for equine acute laminitis.
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NISTOR, VICTOR, and CHRISTOPH SCHWAB. "HIGH-ORDER GALERKIN APPROXIMATIONS FOR PARAMETRIC SECOND-ORDER ELLIPTIC PARTIAL DIFFERENTIAL EQUATIONS." Mathematical Models and Methods in Applied Sciences 23, no. 09 (2013): 1729–60. http://dx.doi.org/10.1142/s0218202513500218.
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Let D ⊂ ℝd, d = 2, 3, be a bounded domain with piecewise smooth boundary, Y = ℓ∞(ℕ) and U = B1(Y), the open unit ball of Y. We consider a parametric family (Py)y∈U of uniformly strongly elliptic, second-order partial differential operators Py on D. Under suitable assumptions on the coefficients, we establish a regularity result for the solution u of the parametric boundary value problem Py u(x, y) = f(x, y), x ∈ D, y ∈ U, with mixed Dirichlet–Neumann boundary conditions on ∂d D and, respectively, on ∂n D. Our regularity and well-posedness results are formulated in a scale of weighted Sobolev spaces [Formula: see text] of Kondrat'ev type. We prove that the (Py)y ∈ U admit a shift theorem that is uniform in the parameter y ∈ U. Specifically, if the coefficients of P satisfy [Formula: see text], y = (yk)k≥1 ∈ U and if the sequences [Formula: see text] are p-summable in k, for 0 < p< 1, then the parametric solution u admits an expansion into tensorized Legendre polynomials Lν(y) such that the corresponding sequence [Formula: see text], where [Formula: see text]. We also show optimal algebraic orders of convergence for the Galerkin approximations uℓ of the solution u using suitable Finite Element spaces in two and three dimensions. Namely, let t = m/d and s = 1/p-1/2, where [Formula: see text], 0 < p < 1. We show that, for each m ∈ ℕ, there exists a sequence {Sℓ}ℓ≥0 of nested, finite-dimensional spaces Sℓ ⊂ L2(U;V) such that the Galerkin projections uℓ ∈ Sℓ of u satisfy ‖u - uℓ‖L2(U;V) ≤ C dim (Sℓ)- min {s, t} ‖f‖Hm-1(D), dim (Sℓ) → ∞. The sequence Sℓ is constructed using a sequence Vμ⊂V of Finite Element spaces in D with graded mesh refinements toward the singularities. Each subspace Sℓ is defined by a finite subset [Formula: see text] of "active polynomial chaos" coefficients uν ∈ V, ν ∈ Λℓ in the Legendre chaos expansion of u which are approximated by vν ∈ Vμ(ℓ, ν), for each ν ∈ Λℓ, with a suitable choice of μ(ℓ, ν).
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Dattoma, V., M. De Giorgi, S. Giancane, P. Manco, and A. E. Morabito. "A parametric associative modelling of aeronautical structural concepts under C 0, C 1 or C 2 continuity constraints." Aeronautical Journal 116, no. 1181 (2012): 727–41. http://dx.doi.org/10.1017/s0001924000007193.
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Abstract In this paper an associative-parametric approach is proposed in order to model the mesh of an aeronautical concept starting from a set of high-level structural primitives. This approach allows the designer to carry out the geometric modelling and the automatic mesh generation within one software environment in a fast and interactive way. The structural optimisation process is then simplified, with a relevant man-hours saving. A lower number of data transfers between different software is, moreover, involved with less problems related to the data corruption. To assure orders of continuity higher than C 0 between adjacent instances, a suitable mathematical description of the structural primitives has been proposed. This description assures the maintenance of the required continuity constraints when the mesh is modified. Appropriate schemes of dependences are identified to guarantee the automatic propagation of the modifications complying with the continuity constraints.
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Galaktionov, V. A. "On blow-up and degeneracy for the semilinear heat equation with source." Proceedings of the Royal Society of Edinburgh: Section A Mathematics 115, no. 1-2 (1990): 19–24. http://dx.doi.org/10.1017/s0308210500024537.
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SynopsisThe asymptotic behaviour of the solution of the semilinear parabolic equation ut = uxx + (1 + u)ln2(l + u) for t > 0, x ∊[−π, π ], ux(t, ± π) = 0 for t > 0 and u(0, x) = u0(x) ≧ 0 in [−π, π], which blows up at a finite time T0, is investigated. It is proved that for some two-parametric set of initial functions u0 the behaviour of u(t, x) near t = T0 is described by the approximate self-similar solution va(t, x) = exp {(T0 −t)−1 cos2 (x/2)} − 1, satisfying the first order nonlinear Hamilton–Jacobi equation vt, = (vx)2 /(1 + v) + (1 + v) ln2 (1 + v). Some open problems of degeneracy near a finite blow-up time for other semilinear or quasilinear parabolic equations with source ut, = Δu + (1 + u) lnβ (1 + u) (β >1), ut, = Δu + uβ(β > l), ut = Δu + eu; ut = ∇. (lnσ(1 + u)∇u)+ (1 + u)lnβ(1 + u) (σ > 0, β > 1) are discussed.
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Bachmayr, Markus, Albert Cohen, Ronald DeVore, and Giovanni Migliorati. "Sparse polynomial approximation of parametric elliptic PDEs. Part II: lognormal coefficients." ESAIM: Mathematical Modelling and Numerical Analysis 51, no. 1 (2016): 341–63. http://dx.doi.org/10.1051/m2an/2016051.
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We consider the linear elliptic equation − div(a∇u) = f on some bounded domain D, where a has the form a = exp(b) with b a random function defined as b(y) = ∑ j ≥ 1yjψj where y = (yj) ∈ ℝNare i.i.d. standard scalar Gaussian variables and (ψj)j ≥ 1 is a given sequence of functions in L∞(D). We study the summability properties of Hermite-type expansions of the solution map y → u(y) ∈ V := H01(D) , that is, expansions of the form u(y) = ∑ ν ∈ ℱuνHν(y), where Hν(y) = ∏j≥1Hνj(yj) are the tensorized Hermite polynomials indexed by the set ℱ of finitely supported sequences of nonnegative integers. Previous results [V.H. Hoang and C. Schwab, M3AS 24 (2014) 797−826] have demonstrated that, for any 0 <p ≤ 1, the ℓp summability of the sequence (j ∥ψj ∥L∞)j ≥ 1 implies ℓp summability of the sequence (∥ uν∥V)ν ∈ ℱ. Such results ensure convergence rates n− s with s = (1/p)−(1/2) of polynomial approximations obtained by best n-term truncation of Hermite series, where the error is measured in the mean-square sense, that is, in L2(ℝN,V,γ) , where γ is the infinite-dimensional Gaussian measure. In this paper we considerably improve these results by providing sufficient conditions for the ℓp summability of (∥uν∥V)ν ∈ ℱ expressed in terms of the pointwise summability properties of the sequence (|ψj|)j ≥ 1. This leads to a refined analysis which takes into account the amount of overlap between the supports of the ψj. For instance, in the case of disjoint supports, our results imply that, for all 0 <p< 2 the ℓp summability of (∥uν∥V)ν ∈ ℱfollows from the weaker assumption that (∥ψj∥L∞)j ≥ 1is ℓq summable for q := 2p/(2−p) . In the case of arbitrary supports, our results imply that the ℓp summability of (∥uν∥V)ν ∈ ℱ follows from the ℓp summability of (jβ∥ψj∥L∞)j ≥ 1 for some β>1/2 , which still represents an improvement over the condition in [V.H. Hoang and C. Schwab, M3AS 24 (2014) 797−826]. We also explore intermediate cases of functions with local yet overlapping supports, such as wavelet bases. One interesting observation following from our analysis is that for certain relevant examples, the use of the Karhunen−Loève basis for the representation of b might be suboptimal compared to other representations, in terms of the resulting summability properties of (∥uν∥V)ν ∈ ℱ. While we focus on the diffusion equation, our analysis applies to other type of linear PDEs with similar lognormal dependence in the coefficients.
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Vasconcelos, Luiz, Piotr Kijanka, and Matthew W. Urban. "Parametric evaluation of Kelvin-Voigt dispersion curve fitting." Journal of the Acoustical Society of America 153, no. 3_supplement (2023): A313. http://dx.doi.org/10.1121/10.0018970.
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Ultrasound shear wave elastography (SWE) is a useful technique for non-invasive tissue assessment. For effective quantitative analysis the employment of physical models is necessary for rheological parameter estimation, such as the Kelvin-Voigt (KV) model. From SWE data, the frequency response can be calculated, and the shear wave velocity dispersion can be fit, yielding the shear elasticity and shear viscosity, μ1 and μ2, respectively. In this study, a parametric evaluation is performed using staggered-grid finite-difference simulations of materials with μ1 = 1–25 kPa (increment: 1 kPa) and μ2 = 0–10 Pa s (increment: 0.5 Pa s), with an acoustic radiation force push of f-number equal to 2. The novel Stockwell transform combined with a slant frequency-wavenumber analysis (GST-SFK) was compared with the two-dimensional Fourier transform for dispersion curve estimation over a variety of frequency ranges. Regardless of dispersion curve estimation technique, the accuracy of estimating μ1 is confounded for μ2 values above 5 Pa s. It was found that KV fitting benefits from wider frequency ranges (up to 1kHz), with lower μ1 and μ2 estimation errors. The GST-SFK was the best dispersion curve calculation technique, yet the KV fitting process was found to be unreliable for parameter estimation in highly viscous media.
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Shwan, Bestun J. "Passive earth pressure analysis considering hydraulic and mechanical hysteresis for unsaturated soil." PLOS ONE 20, no. 1 (2025): e0310536. https://doi.org/10.1371/journal.pone.0310536.
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This paper addresses the mechanical characteristics of a passive earth pressure problem taking into account water retention curve (SWRC) hysteresis. Both hydraulic (drying and wetting cycles) and mechanical hysteresis were considered. Parametric studies were carried out at various air entry values (AEV = 5–30 kPa), different wall frictions (δ = 0, 0.33 ϕ, 0.5 ϕ, 0.67 ϕ and δ = ϕ), and unsaturated conditions (covering the zone from the fully saturated to the transition suction, 0 - ~40 kPa) using an upper bound theorem. The numerical results were compared with a passive earth pressure equation based on the limit equilibrium method. The results indicated significant influences of SWRC hysteresis and wall frictions on the passive thrust (Pp) for the modeled suction profiles. An increase of 1.31-fold in Pp was obtained when the AEV changed from 10 to 20 kPa at the water table (Hw) = -2 m. Additionally, the combined effects of AEV and δ were found to be significant. An increase of 4.14-fold in Pp at Hw = -3 m was obtained when comparing the case of AEV = 30 kPa and δ = ϕ with AEV = 5 kPa and δ = 0. Based on the parametric studies, a series of design charts of the exerted passive thrust were proposed.
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RAM, B.DHALE, S. KORE SUHAS, S.T. JAGTAP Prof., B.WATHARKAR PRATHAMESH, and R.CHAVAN PRATHAMESH. "DESIGN, ANALYSIS AND MANUFACTURING OF GO-KART CHASSIS." IJIERT - International Journal of Innovations in Engineering Research and Technology NITET-18 (March 17, 2018): 24–33. https://doi.org/10.5281/zenodo.1451455.
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<strong><strong> </strong>This report aims to model,simulate,perform the static and dynamic analysis and fabrication of a go kart chassis consisting of Circular beams. Modelling,simulations are performed using mo delling software i.e. PTC CREO 2 0 and analysis on ANSYS V 14.5 . The maximum deflection is determined by performing dynamic analysis. The chassis is designed such that it requires less material and as well as it is strong enough to withstand the various impacts on it. Strength and light weight were our basic consideration throughout the design of thechas sis of the kart. Hence,AISI 1018 was selected as an appropriate material for design which is a medium carbon steel with properties such as light weight,high tensile strength,high machinability,better weldability,etc. All the impacts and stresses were analysed by considering the severe working conditions and then the design was analysed in the analysis software. Step by step modifications in design were made as found necessary and as analysed on the software. After the complete analysis and the approval of design by inspecting it in all the modes of failure the design was finalized and was selected to fabricate which will not fail in any extreme criteria of stresses or load induced.</strong> <strong>https://www.ijiert.org/paper-details?paper_id=141204</strong>