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Vakhnenko-type equations play a critical role in nonlinear electromagnetic and optical fiber applications. In this article, we present a new advancement in high-frequency wave propagation in electromagnetic and optical fiber applications by investigating an extended generalization of the Vakhnenko equation. In our study, we employ the bilinear method and introduce an auxiliary function that combines exponential and cosine functions. By utilizing this approach, we are able to derive two distinct sets of analytical solutions for the equation. By choosing suitable parameters involved in the solutions, we identify the presence of soliton molecules and soliton bifurcation in the equation. Furthermore, for the soliton molecules, we note the existence of two distinct types of phase transitions: (i) a transition from soliton molecules to loop-like breathers, and (ii) a transition from soliton molecules to intersection solitons. Regarding soliton bifurcation, we observe phase transitions among loop-like, cusp-like, and peak-like solitons. Moreover, the results of this study illuminate that the structures of all solitons, within the context of soliton molecules and soliton bifurcation, remain stable throughout the phase transitions. This stability carries considerable significance for practical applications. [ABSTRACT FROM AUTHOR]

Semaglutide, a glucagon-like peptide-1 receptor agonist, is clinically used as a glucose-lowering and weight loss medication due to its effects on energy metabolism. In heart failure, energy production is impaired due to altered mitochondrial function and increased glycolysis. However, the impact of semaglutide on cardiomyocyte metabolism under pressure overload remains unclear. Here we demonstrate that semaglutide improves cardiac function and reduces hypertrophy and fibrosis in a mouse model of pressure overload-induced heart failure. Semaglutide preserves mitochondrial structure and function under chronic stress. Metabolomics reveals that semaglutide reduces mitochondrial damage, lipid accumulation, and ATP deficiency by promoting pyruvate entry into the tricarboxylic acid cycle and increasing fatty acid oxidation. Transcriptional analysis shows that semaglutide regulates myocardial energy metabolism through the Creb5/NR4a1 axis in the PI3K/AKT pathway, reducing NR4a1 expression and its translocation to mitochondria. NR4a1 knockdown ameliorates mitochondrial dysfunction and abnormal glucose and lipid metabolism in the heart. These findings suggest that semaglutide may be a therapeutic agent for improving cardiac remodeling by modulating energy metabolism. Semaglutide is used for glucose control and weight reduction. Here, the authors show that it enhances myocardial metabolism by targeting Creb5/NR4a1, protecting against cardiac remodeling and offering a therapeutic approach for heart failure through metabolic regulation. [ABSTRACT FROM AUTHOR]

Soliton dynamics often exhibit a rich diversity and complexity, emerging from myriad combinations of nonlinearities and dispersions within nonlinear dynamical systems. This endeavor contributes to the novel exploration of intricate soliton interactions. In this paper, we investigate a multi-component Maccari system which can be used to depict optical pulse motions in multi-mode optical fibers. By employing the bilinear method, we obtain the system's analytical second-order solutions involving abundant parameters. Under taking suitable parameter settings, we observe some novel soliton interaction dynamics: soliton resonances from local to global ranges, transitions from soliton molecules to breathers, semi-elastic soliton collisions and soliton bifurcations (namely solitons' fission and fusion). Especially, all solitons in resonances, molecules and bifurcations hold stable propagation states. The findings also reveal new energy transition mechanism during soliton interactions by semi-elastic collisions and soliton bifurcations. [ABSTRACT FROM AUTHOR]

In this study, we employ the bilinear method to construct Nth-order solutions for a nonlinear (3+1)-dimensional shallow water equation. Subsequently, we delve into a comprehensive exploration of novel dynamical features within the equation, including soliton interactions, soliton bifurcations, soliton molecules, breather and soliton interactions, breather molecules, and breather-to-soliton transitions. Analytical expressions for the constraint conditions required to generate soliton bifurcations and soliton molecules are presented. Our study reveals that the newly obtained waves exhibit distinctive characteristics: they can form multi-layered step-like flat blocks, propagate with stable energies and shapes, thereby reflecting an intrinsic balance between nonlinearities and dispersions. We also verify that this equation has an infinite number of conservation laws. These intriguing findings contribute to a deeper understanding of the dynamic behaviors exhibited by solitons, breathers, and their hybrid forms within the realm of shallow water waves characterized by nonlinear motions. [ABSTRACT FROM AUTHOR]

In this study, under investigation is a (2+1)-dimensional coupled Maccari system which includes a complex dependent variable and a real dependent variable. By constructing new bilinear forms, we derive the semi-rational and rational solutions which exhibit as lump waves. Through the careful manipulation to the parameters, we unveil the phase transitions of the lump waves between different structures. The results show that there are distinct phase transition patterns for two dependent variables in the system. [ABSTRACT FROM AUTHOR]

In this article, we investigate the dynamical interaction behavior of a short pulse equation in optical fibers with fast-varying packets. We systematically unearth the interaction dynamics between solitons, breathers, and their hybrid forms. Using the bilinear method, we explicitly calculate the first- to fourth-order solutions. We categorize the solutions into three classes based on their dispersion coefficients: stripe-loop-like soliton, breather, and their hybrid form. We observe the existence of bright and dark solitons. Additionally, a breather may consist of periodical peak-trough waves and periodical kink-loop-like waves. As the order of the solutions increases, there are abundant and complicated interaction behaviors for the solitons, breathers, and their hybrid forms due to these rich patterns. [ABSTRACT FROM AUTHOR]

Soliton resonances and soliton molecules have become a hot topic in the field of nonlinear science and engineering in recent years due to their potential applications. This work presents a systematic study of the soliton interaction dynamics of the Maccari system. Using the bilinear method, explicit first- and second-order solutions of the system are derived for the system. With these solutions and carefully chosen parameters, we observe various soliton interaction phenomena, such as soliton resonances, soliton molecules, soliton oscillations, and heterotypic solitons, including the V- and Y-type soliton, for the two dependent variables under two coordinate systems: space and spatiotemporal coordinate systems, respectively. Notably, we find that soliton molecules and heterotypic solitons exhibit completely different features under the two coordinate systems. The constraint conditions for the existence of soliton molecules are more restrictive in the spatiotemporal coordinate, and the occurrence of V- and Y-type soliton patterns is relatively rare in this coordinate system. [ABSTRACT FROM AUTHOR]

The AB system is a critical component of fluid dynamics, as it is capable of modeling the nonlinear wave motions in two-layer fluids. In this study, we investigate soliton molecules and soliton resonance in the AB system. We employ the Darboux transformation scheme to derive new, explicit expressions for one- to four-order soliton solutions for the system. These solutions include spectrum parameter allowing us to explore novel soliton resonances and soliton molecules in the system. We identify two types of soliton resonances: local and global. We also reveal the evolution dynamics from local to global resonances. Global soliton resonances can be understood as the limit of local soliton resonances. Additionally, based on both the phase parameters, we report the existence of soliton molecules in the AB system. We further discover that parallel soliton molecules without entanglement become global soliton resonances with entanglement as the phase parameters approach zero. This finding holds great significance for the system as it provides theoretical evidence that the system possesses a breather-like wave structure, where two or multiple solitons exhibit mutual entanglement and stable energy. These findings enhance our understanding of the AB system and shed light how to manage and control these stable resonant solitons. [ABSTRACT FROM AUTHOR]

Background and Purpose: Limonin, a naturally occurring tetracyclic triterpenoid, has extensive pharmacological effects. Its role in cardiac hypertrophy remains to be elucidated. We investigated its effects on cardiac hypertrophy along with the potential mechanisms involved.Experimental Approach: The effects of limonin on cardiac hypertrophy in C57/BL6 mice caused by aortic banding, plus neonatal rat cardiac myocytes (NRCMs) stimulated with phenylephrine to induce cardiomyocyte hypertrophy in vitro were investigated.Key Results: Limonin markedly improved the cardiac function and heart weight in aortic banded mice. Limonin-treated mice and NRCMs also produced fewer cardiac hypertrophy markers than those treated with the vehicle in the hypertrophic groups. Sustained aortic banding- or phenylephrine-stimulation impaired cardiac sirtuin 6 (SIRT6) protein levels, which were partially reversed by limonin associated with enhanced activity of PPARα. Sirt6 siRNA inhibited the anti-hypertrophic effects of limonin in vitro. Interestingly, limonin did not influence Sirt6 mRNA levels, but regulated ubiquitin levels. Thus, the protein biosynthesis inhibitor, cycloheximide and proteasome inhibitor, MG-132, were used to determine SIRT6 protein expression levels. Under phenylephrine stimulation, limonin increased SIRT6 protein levels in the presence of cycloheximide, but it did not influence SIRT6 expression in the presence of MG-132, suggesting that limonin promotes SIRT6 levels by inhibiting its ubiquitination degradation. Furthermore, limonin inhibited the degradation of SIRT6 by activating ubiquitin-specific peptidase 10 (USP10), while Usp10 siRNA prevented the beneficial effects of limonin.Conclusion and Implications: Limonin mediates the ubiquitination and degradation of SIRT6 by activating USP10, providing an attractive therapeutic target for cardiac hypertrophy. [ABSTRACT FROM AUTHOR]

In this paper, we perform a systematical study on the breathers of the AB system in fluids. The expressions of the first- to third-order breather solutions are explicitly computed through applying the Darboux transformation method to the system. Some new and interesting features for the breathers are found out as follows. Firstly, in addition to the general breathers, Ak-breathers and Ma-breathers are observed. Further, the corresponding spectrum parameter constrains to form the three breathers are given. Secondly, the dependent variables A and B in the system possess a few of novel spatio-temporal patterns for the periodical wave packets which form the breathers: two-petals, three-petals and four-petals. Thirdly, the interactions between two- or multiple-breathers are elastic. Lastly, there are rich interaction patterns, such as, Ak-breathers and Ma-breather cross vertically, breathers parallel with the same speed. [ABSTRACT FROM AUTHOR]

Soliton resonances and soliton molecules play a vital role to generate stable high-energy waves in nonlinear system. Meanwhile, higher-order dispersions and higher-order nonlinearity effects are often introduced in optical models because new optical propagation media have constantly been developed. This article's motivation is to explore the optical soliton resonances and soliton molecules for the Lakshmanan–Porsezian–Daniel system governed by a four-order nonlinear Schrödinger equation arising in nonlinear optics. Via applying the Darboux transformation method, we obtained the system's analytical multi-soliton solutions. Then, through managing the spectrum parameters and initial phase parameters, novel soliton resonances and soliton molecules are discovered for the first time to the system. Our study reveals a few of significant properties of the soliton resonances and soliton molecules for the system: (i) The formation mechanism from local soliton resonances to soliton molecules is discovered. The soliton molecules can be established as a limit of local soliton resonances; (ii) the system energy carried by the soliton will obviously increase as local soliton resonances and soliton molecules occur; (iii) the spatiotemporal patterns of soliton molecules will be becoming more complex as the order of soliton solutions increases; (iv) the wave density of soliton molecules will grow with the increase in the weight coefficient of higher-order dispersion and higher-order nonlinearity. These new results indicate that the Lakshmanan–Porsezian–Daniel system may not only generate higher-energy solitons, but also carry richer optical information. [ABSTRACT FROM AUTHOR]

In this work, we study the soliton resonances for a transient stimulated Raman scattering system. The multi-soliton solutions are constructed via applying Darboux transformation technique for the system. By controlling the spectrum eigenvalues of the vector matrices in Darboux transformation, we reveal that there does exist interesting soliton resonances for the system. As any two solitons resonate completely, they will emerge into one and are separated by continuous single waves arranged periodically. Through observing the evolution from partial resonances to complete resonances, we acquire the formation mechanism of soliton resonances. The condition to generate the complete resonances is that any two spectrum eigenvalues should be a pair of complex numbers symmetrized with respect to the imaginary axis. Furthermore, the impacts of the phases on the complete resonant solitons are also investigated. The phase parameters can control the distances between the resonant solitons. Besides, there are exotic and ingenious geometric patterns for the resonant solitons. [ABSTRACT FROM AUTHOR]

By the means of reconstructing the Darboux transformation to the Manakov system, we obtain the new explicit solutions composed of a rogue wave and a breather for the system. Via controlling the parameter involved in the solutions, we reveal a novel 'firewall' effect during the rogue wave and breather interactions. There are three cases of inelastic collisions and one type of semi-elastic collision between the rogue wave and breather. Particularly, either of the rogue wave or breather cannot cross over another during the collision. [ABSTRACT FROM AUTHOR]

In this work, we develop a new (3+1)-dimensional Sakovich equation to describe nonlinear wave propagation. We use the truncation expansion method to confirm the Painlevé integrability of the newly established equation. Then, its general soliton solution and multiple-soliton solutions are constructed. We also verify that the equation possesses soliton molecules. A few of interesting features for the equation are discovered. [ABSTRACT FROM AUTHOR]

We report exotic hybrid rogue wave and breather solutions for a complex mKdV equation describing soliton dynamics in few-cycle ultra-short pulse optics. Starting from the Lax pair, the higher-order Darboux transformations for the equation are constructed. Then, a series of theorems to compute the hybrid rogue wave and breather solutions are constructed and proved. We also demonstrate the interaction features between rogue waves and breathers by controlling parameters. These results are of importance to understand nonlinear wave dynamics in optics. [ABSTRACT FROM AUTHOR]

In this paper, we develop a new extended Kadomtsev–Petviashvili (eKP) equation. We use the Painlevé analysis to confirm the integrability of the eKP equation. We derive the bilinear form, multiple soliton solutions and lump solutions via using the Hirota's direct method. Moreover, the soliton, breather and lump interaction solutions for this model are also obtained as well. Graphs are drawn to illustrate the abundant dynamical behaviors of the obtained solutions. [ABSTRACT FROM AUTHOR]

Indigenous animals show unique gut microbiota (GM) in the Tibetan plateau. However, it is unknown whether the hypertensive indigenous people in plateau also have the distinct gut bacteria, different from those living in plains. We sequenced the V3-V4 region of the gut bacteria 16S ribosomal RNA (rRNA) gene of feces samples among hypertensive patients (HPs) and healthy individuals (HIs) from 3 distinct altitudes: Tibetans from high altitude (3600–4500 m, n = 38 and 34), Hans from middle altitude (2260 m, n = 49 and 35), and Hans from low altitude (13 m, n = 34 and 35) and then analyzed the GM composition among hypertensive and healthy subgroups using the bioinformatics analysis, respectively. The GM of high-altitude Tibetan and middle-altitude Han HPs presented greater α- and β-diversities, lower ratio of Firmicutes/Bacteroidetes (F/B), and higher abundance of beneficial Verrucomicrobia and Akkermansia than the low-altitudes HPs did. The GM of high-altitude Tibetan and middle-altitude HIs showed greater α-diversity and lower ratio of F/B than the low-altitudes HIs did. But, β-diversity and abundance of Verrucomicrobia and Akkermansia among different subgroups of HIs did not show any differences. Conclusively, the high-altitude Tibetan and middle-altitude Han HPs have a distinct feature of GM, which may be important in their adaptation to hypertension in the plateau environments. [ABSTRACT FROM AUTHOR]

Indigenous animals show unique gut microbiota (GM) in the Tibetan plateau. However, it is unknown whether the hypertensive indigenous people in plateau also have the distinct gut bacteria, different from those living in plains. We sequenced the V3-V4 region of the gut bacteria 16S ribosomal RNA (rRNA) gene of feces samples among hypertensive patients (HPs) and healthy individuals (HIs) from 3 distinct altitudes: Tibetans from high altitude (3600–4500 m, n = 38 and 34), Hans from middle altitude (2260 m, n = 49 and 35), and Hans from low altitude (13 m, n = 34 and 35) and then analyzed the GM composition among hypertensive and healthy subgroups using the bioinformatics analysis, respectively. The GM of high-altitude Tibetan and middle-altitude Han HPs presented greater α- and β-diversities, lower ratio of Firmicutes/Bacteroidetes (F/B), and higher abundance of beneficial Verrucomicrobia and Akkermansia than the low-altitudes HPs did. The GM of high-altitude Tibetan and middle-altitude HIs showed greater α-diversity and lower ratio of F/B than the low-altitudes HIs did. But, β-diversity and abundance of Verrucomicrobia and Akkermansia among different subgroups of HIs did not show any differences. Conclusively, the high-altitude Tibetan and middle-altitude Han HPs have a distinct feature of GM, which may be important in their adaptation to hypertension in the plateau environments. [ABSTRACT FROM AUTHOR]

The main attention of this study is focused on the interaction dynamics of breather, and hybrid solitons and breather for an extended generalization of Vakhnenko equation. The general form of the N-order auxiliary function is first derived by the Hirota bilinear method. Then, the N-order solutions can be obtained. When N ≥ 2 , the loop-like breather may emerge by taking the dispersion coefficients as conjugate complex number. The breather is like a magical spring with good elasticity, changeable period and thickness. Furthermore, novel interaction features between breathers, between soliton/solitons and breather/breathers, are observed by visualizing method. The results show that there are abundant dynamics during the interactions, such as elastic collision, phase shift, amplitude amplification, collapse and bulge effect. [ABSTRACT FROM AUTHOR]

We report the novel colliding dynamics of the rogue waves (RWs) for a three-component transient stimulated Raman scattering system arising from nonlinear optics. The N-order RW solutions are constructed by utilizing the generalized Darboux transformation scheme. Then, the dynamics of the RWs are analyzed. As N ≥ 2 , the multiple RWs collide towards a central point. During the collisions and interactions, the peaks and troughs increase greatly. It is also interesting and magical that all the RWs possess exquisite symmetrical structures. [ABSTRACT FROM AUTHOR]

A particular attention is paid on a generalized nonlinear Boussinesq equation which can be used to describe the wave dynamics in fluids. Via symbolic computation method, analytical N-soliton solutions, three types of breather solutions (namely, Kuznetsov-Ma, Akhmediev and generalized breather solutions), and rogue wave solutions are obtained. The extreme points of rogue waves are analyzed in detail. Furthermore, a type of novel X-like soliton is observed. [ABSTRACT FROM AUTHOR]

A generalized nonlinear Schrödinger system is investigated, which can be used to describe the optical pulse propagation in inhomogeneous optical fibers with the fourth- and third-order dispersions operators. The Darboux transformation method is extended to construct a mixed breather and rogue wave solution for the system. The interaction behaviors between the breather and rogue wave are studied. As a novel result, the energy transition between the breather and rogue wave is observed. Furthermore, the impacts of the different operators on the mixed solution are analyzed. [ABSTRACT FROM AUTHOR]

A bilinear transformation method is proposed to find the rogue wave solutions for a generalized fourth‐order Boussinesq equation, which describes the wave motion in fluid mechanics. The one‐ and two‐order rogue wave solutions are explicitly constructed via choosing polynomial functions in the bilinear form of the equation. The existence conditions for these solutions are also derived. Furthermore, the system parameter controls on the rogue waves are discussed. The three parameters involved in the equation can strongly impact the wave shapes, amplitudes, and distances between the wave peaks. The results can be used to deeply understand the nonlinear dynamical behaviors of the rogue waves in fluid mechanics. [ABSTRACT FROM AUTHOR]

A generalized (3 + 1)-dimensional Kadomtsev–Petviashvili equation is investigated, which can be used to describe nonlinear wave propagation in fluids. Through choosing appropriate polynomial functions in bilinear form derived according Hirota bilinear transformation, one and two rogue wave solutions, and soliton and rogue wave mixed solution are constructed. Furthermore, based on the mixed solution, interaction and evolution behavior between the soliton and rogue wave is discussed. The result shows that the soliton will be gradually swallowing up the rogue wave with the increase of time. During the process, the energy carried by the rogue wave is absorbed by the soliton. [ABSTRACT FROM AUTHOR]

The Kraenkel-Manna-Merle system is investigated, which describes the propagations of the ferromagnetic particles in ferrite materials. A new series of the solutions are obtained via the auxiliary equation method. These solutions include periodic traveling wave solutions in Jacobi elliptic functions and soliton solutions in hyperbolic functions. Some of them are demonstrated in visualization. There exist loop-like periodic waves and loop-like solitons between independent variables related to the magnetization and the external magnetic fields vs. the time and space variables. The parameter influences on the periodic wave solutions are also discussed. [ABSTRACT FROM AUTHOR]

A particular attention is paid to investigate the Kraenkel-Manna-Merle (KMM) system, which can describe the nonlinear short-wave propagation in saturated ferromagnetic materials with zero-conductivity in an external field. A class of exact soliton solutions is constructed via the generalized G′/G-expansion method. Some novel soliton structures are excited by choosing the arbitrary functions in the solution as certain specific functions. Hump-soliton, cusp-soliton, loop-soliton, and kink-soliton are observed graphically. The results reveal the system theoretically possesses extremely rich soliton structures. [ABSTRACT FROM AUTHOR]

The Heisenberg ferromagnetic spin chain equation is investigated. By applying the improved F‐expansion method (Exp‐function method) and the Jacobi elliptic method, respectively, a series of exact solutions is constructed. The parametric conditions of the existence for the solutions are presented. These solutions comprise periodic wave solutions, doubly periodic wave solutions, and dark and bright soliton solutions, which are expressed in several different function forms, namely, Jacobi elliptic function, trigonometric function, hyperbolic function, and exponential function. The results illustrate that the Exp‐function method is a powerful symbolic algorithm to look for new solutions for the nonlinear evolution systems. [ABSTRACT FROM AUTHOR]

A non-traveling wave solution of a generalized Vakhnenko equation arising from the high-frequent wave motion in a relaxing medium is derived via the extended Riccati mapping method. The solution includes an arbitrary function of an independent variable. Based on the solution, two hyperbolic functions are chosen to construct new solitons. Novel single-loop-like and double-loop-like solitons are found for the equation. [ABSTRACT FROM AUTHOR]

Applying a direct symbolic computation method combined with variable transformations, some new Jacobi elliptic function solutions are obtained to the short-pulse equation in nonlinear optics. When Jacobi elliptic function modulus m→1 or 0, the travelling wave solutions degenerate to two types of solutions, namely, the loop-like soliton solution and the trigonometric function solution. [ABSTRACT FROM AUTHOR]

In this paper, a coupled monomode step-index optical fiber system is under investigation, which can be governed by a coupled Schrödinger equation. Though extending the Jacobi elliptic function method in complex form, a series of Jacobi elliptic function solitons are obtained for the equation. These solutions can be expressed in the form of doubly periodic waves. When the modulus of Jacobi elliptic function tends to 1, the bright and dark optical solitons are observed. Furthermore, the modulus of Jacobi elliptic function can control the periodic wave density. The wave width and direction of the solitons are effected by parameters. [ABSTRACT FROM AUTHOR]

A nonlinear waveguide directional coupler system in optical fibers is investigated. The system can be modelled as coupled nonlinear Schrödinger equations. Applying Hirota bilinear transformation method, analytic one- and two-soliton solutions are constructed. Furthermore, a novel class of solitons resonant behavior is observed. The solitons are split into multiple wave peaks around colliding point. The impacts of main parameters on soliton collisions are systematically discussed. Group velocity dispersion parameter and group velocity mismatch parameter can impact and control the resonant effects. Meanwhile, the complex parameters in the soliton solutions can determine resonant peaks intensity. [ABSTRACT FROM AUTHOR]