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排序方式: 共有159条查询结果,搜索用时 15 毫秒
121.
Fatahi Negin Hoat D. M. Laref Amel Amirian Shirin Reshak A. H. Naseri Mosayeb 《The European Physical Journal B - Condensed Matter and Complex Systems》2020,93(7):1-7
The European Physical Journal B - The present study investigates amplitude death in an oscillator network with asymmetric connection delays and a tree graph topology. A frequency domain analysis... 相似文献
122.
Oumaima Zidi Nessrine Souai Henda Raies Farhat Ben Ayed Amel Mezlini Sonia Mezrioui Fabrice Tranchida Jean-Marc Sabatier Amor Mosbah Ameur Cherif Laetitia Shintu Soumaya Kouidhi 《Molecules (Basel, Switzerland)》2021,26(8)
Breast cancer (BC) is the most common form of cancer among women worldwide. Despite the huge advancements in its treatment, the exact etiology of breast cancer still remains unresolved. There is an increasing interest in the role of the gut microbiome in modulating the anti-cancer therapeutic response. It seems that alteration of the microbiome-derived metabolome potentially promotes carcinogenesis. Taken together, metabolomics has arisen as a fascinating new omics field to screen promising metabolic biomarkers. In this study, fecal metabolite profiling was performed using NMR spectroscopy, to identify potential biomarker candidates that can predict response to neoadjuvant chemotherapy (NAC) for breast cancer. Metabolic profiles of feces from patients (n = 8) following chemotherapy treatment cycles were studied. Interestingly, amino acids were found to be upregulated, while lactate and fumaric acid were downregulated in patients under the second and third cycles compared with patients before treatment. Furthermore, short-chain fatty acids (SCFAs) were significantly differentiated between the studied groups. These results strongly suggest that chemotherapy treatment plays a key role in modulating the fecal metabolomic profile of BC patients. In conclusion, we demonstrate the feasibility of identifying specific fecal metabolic profiles reflecting biochemical changes that occur during the chemotherapy treatment. These data give an interesting insight that may complement and improve clinical tools for BC monitoring. 相似文献
123.
Ilhem Djellit Mohamed Lamine Sahari Amel Hachemi 《Journal of Applied Analysis & Computation》2013,3(1):11-20
In this work, we consider some dynamical properties and specific contactbifurcations of a discrete-time predator-prey system having inverseswith vanishing denominator. The dynamics is investigated by usingconcepts of focal points, prefocal curves and bifurcation theory.The system undergoes flip bifurcation and Neimark-Sacker bifurcation.Numerical simulations are presented not only to illustrate our resultswith the theoretical analysis, but also to confirm further the complexityof the dynamical behaviors as extinction, persistence and permanence. 相似文献
124.
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126.
N.I. Amel’kin 《Journal of Applied Mathematics and Mechanics》2010,74(5):513-523
For a dynamically symmetrical satellite carrying a two-degree-of-freedom powered gyroscope, all the relative equilibria in a circular orbit are found as a function of the angular momentum of the rotor and the angle between the precession axis of the gyroscope and the plane of dynamical symmetry. The case with no spring on the axis of the gyroscope frame and the case with a spring whose stiffness satisfies definite conditions are considered. The secular stability of the equilibria is investigated. For a system with dissipation in the axis of the gyroscope frame, the Barbashin–Krasovskii theorem is used to perform a detailed analysis, which enables the character of the Lyapunov stability of all the equilibria to be determined, with the exception of a few points. The results of a numerical solution of the problem of the optimal values of the system parameters, for which asymptotically stable equilibria are obtained with maximum speed, are presented. 相似文献
127.
N.I. Amel’kin 《Journal of Applied Mathematics and Mechanics》2010,74(4):406-415
A method that enables a conclusion to be drawn regarding the nature of the Lyapunov stability of the equilibria positions of autonomous systems with partial dissipation from the nature of the secular stability and truncated equations of the linear approximation is developed based on the Barbashin–Krasovskii theorem. The method is used to investigate the stability of the equilibria of a satellite carrying a two-degree-of-freedom powered gyroscope with dissipation in the axis of the frame in a circular orbit. For the case when the axis of the gyroscope frame is oriented parallel to one of the principal axes of inertia of the satellite, the nature of the Lyapunov stability of all the equilibria, with the exception of a few branching points, is determined. It is established that gyroscopic stabilization, which is possible when there is no dissipation in the axis of the frame for certain equilibria that are unstable in the secular sense, breaks down when dissipation occurs. 相似文献
128.
Nesrine Louhichi Amel Houas Naoufel Ben Hamadi Moncef Msaddek 《Journal of heterocyclic chemistry》2012,49(2):267-271
In explorations of syntheses and chemistry of spiroheterocycles, we found that the reaction of 2‐diazopropane with (E)‐α‐arylidenepyrrolin‐2‐one, (E)‐α‐arylidene‐γ‐butyrolactone, and (E)‐arylidene‐N‐arylsuccinimide derivatives produced spiro‐Δ1‐pyrazolines. The photolysis of Δ1‐pyrazolines has led to cyclopropanes. The structures of the obtained adducts have been assigned by means of spectroscopic measurements. J. Heterocyclic Chem., (2011). 相似文献
129.
Results of kaolin modification by thermal activation, sonication and 3% solution of acetic acid are considered. It is shown that the introduction of thermally activated kaolin to compositions based on styrene–acrylic filming agents increases the adhesion characteristics by 1.25–1.4 times (for steel and cement–sand surfaces) and cohesive strength by 1.5–2 times. 相似文献
130.
Experimental Techniques - 相似文献