Search

The Helmholtz equation plays a crucial role in the study of wave propagation, underwater acoustics, and the behavior of waves in the ocean environment. The Helmholtz equation is also used to describe propagation through ocean waves, such as sound waves or electromagnetic waves. This paper presents the Elzaki transform residual power series method (E T-RPSM) for the analytical treatment of fractional-order Helmholtz equation. To develop this scheme, we combine Elzaki transform (E T) with residual power series method (RPSM). The fractional derivatives are described in Caputo sense. The E T is capable of handling the fractional order and turning the problem into a recurrence form, which is the novelty of our paper. We implement RPSM in such a way that this recurrence relation generates the results in the form of an iterative series. Two numerical applications are considered to demonstrate the efficiency and authenticity of this scheme. The obtained series are determined very quickly and converge to the exact solution only after a few iterations. Graphical plots and absolute error are shown to observe the authenticity of this suggested approach. [ABSTRACT FROM AUTHOR]

Stochastic Magnetic Tunnel Junctions (SMTJs) emerge as a promising candidate for neuromorphic computing. The inherent stochasticity of SMTJs makes them ideal for implementing stochastic synapses or neurons in neuromorphic computing. However, the stochasticity of SMTJs may impair the performance of neuromorphic systems. In this study, we conduct a systematic examination of the influence of three stochastic effects (shift, change of slope, and broadening) on the sigmoid activation function. We further explore the implications of these effects on the reconstruction performance of Restricted Boltzmann Machines (RBMs). We find that the trainability of RBMs is robust against the three stochastic effects. However, reconstruction error is strongly related to the three stochastic effects in SMTJs-based RBMs. Significant reconstruction error is found when the stochastic effect is strong. Last, we identify the correlation of the reconstruction error with each stochastic factor. Our results might help develop more robust neuromorphic systems based on SMTJs. [ABSTRACT FROM AUTHOR]

This study presents the modified form of the homotopy perturbation method (HPM), and the Yang transform is adopted to simplify the solving process for the Kuramoto–Sivashinsky (KS) problem with fractal derivatives. This scheme is established by combining the two-scale fractal scheme and Yang transform, which is very helpful to evaluate the approximate solution of the fractal KS problem. Initially, we transfer the fractal problem into its partners using the two-scale fractal approach, and then we use the Yang transform ( T) to obtain the recurrent relation. Second, the HPM is then introduced to deal with the nonlinear elements of the fractal model. The numerical example demonstrates how the suggested technique is incredibly straightforward and precise for nonlinear fractal models. In addition, the graphical error of the proposed fractal model is compared with the calculated results of our suggested approach and the exact results. This graphical error displays the strength and authenticity of our proposed scheme. [ABSTRACT FROM AUTHOR]

This paper presents the concept of a new strategy that examines the analytical solution of the Harry Dym equation (HDEq) with fractional derivative in the Caputo sense. This new approach is called the Mohand homotopy perturbation transform scheme (MHPTS) which is constructed on the basis of the Mohand transform (MT) and the homotopy perturbation method (HPM). The implementation of MT produces the recurrence relation without any assumption and hypothesis theory whereas HPM is additionally used to overcome the nonlinearity in differential problems. Our primary focus is to handle the error analysis in the recurrence relation and generates the solution in the order of series. These obtained results yield the exact solution very rapidly due to its fast convergence. Some graphical representations are demonstrated to show the high efficiency and performance of this approach. [ABSTRACT FROM AUTHOR]

Two conspiracy theories that respectively attribute the origin of COVID-19 to a Chinese research institute and the US, were widely disseminated over China's social media sphere in early 2020. By integrating the social-mediated crisis communication model with the theory of planned behavior, this study investigates predictors of public reactions to these conspiracy claims. The results of a cross-sectional survey discovered that message strategies and forms as well as user types and emotions can variously predict their believing in and diffusing conspiracy theories. Rational appeal and internet efficacy both predict diffusing the theory that attributes its origin to the US but have no effect on diffusing its counterpart. Moreover, family discussion has no effect on diffusing both two theories. These findings suggest that public reactions to coronavirus-related conspiracy theories should be examined in the contexts of not only social media applications but also China's internet regulations, cultural values, and international relations. [ABSTRACT FROM AUTHOR]

A stiffened deep cement mixing (SDCM) pile is a type of composite pile that has a rigid pile at the core that reinforces the deep cement mixing (DCM) pile. An SDCM pile combines the advantages of both a DCM pile (i.e., high lateral friction resistance) and a rigid pile (i.e., high stiffness and strength). This work presents four sets of laboratory model tests that were aimed at investigating the vertical bearing capacity of SDCM piles with different cement contents by monitoring the pile top load, the axial force, the pile settlement, and the pile end resistance. Two failure modes of the SDCM piles were observed during the tests––pile failure (the pile ruptured at the section below the core pile) and punching failure (the pile penetrated into the underlying soil). It was found that the vertical bearing capacity of the SDCM piles increased with cement content, up to the point of punching failure. The pile end resistance increased with the pile top load. When the ultimate bearing capacities of the SDCM piles were reached in the model tests, the ratio between pile end resistance and pile top load ranged from 19.4% to 54.2%, indicating that pile end resistance cannot be ignored. [ABSTRACT FROM AUTHOR]

Rogue waves are usually considered as the large amplitude waves that come from nowhere and disappear without trace. The formation of rogue waves are generally related to the degradation of breather solutions. In some special cases, a special form of the interactions between two solitons can be explained by the breather solutions. The types of soliton collisions are very rich, such as weak interactions, strong interactions, and solitons decay: rogue waves (the large amplitude waves that come from nowhere and disappear without trace), and partial-rogue waves (the large amplitude waves that come from nowhere but leave with a trace). Different from the rogue waves and partial-rogue waves, we mainly study the rogue wave type solutions (the large amplitude waves that come and leave with a trace) from the degeneracy in soliton solutions caused by the interactions of solitons synchronization and resonance in the Rotating reduced Maxwell–Bloch equations, which originated from circularly polarized light propagation on two isotropic electronic field components from optical system. These results systematically illustrate the formation of rogue wave type solutions in terms of boundary conditions, spectral parameters and the number of soliton interactions. [ABSTRACT FROM AUTHOR]

A nonlinear vibration system behaviors always periodically; however, sometimes a vibrating structure, e.g. an empty oil tank, will be collapsed suddenly. This can be explained as a kind of rogue waves. This paper gives a general approach to search for rational breather waves to nonlinear equations including nonlinear vibration systems and dispersive wave systems. A breather type of rogue wave solution which contains two peaks whose amplitudes are two to three times higher than its surrounding waves and generally forms in a short time is constructed. Moreover, by using three-wave method, new breather-type multisolitary coherent structures are presented, the fusion interactions of localized structures are discussed and graphically investigated, showing some novel features and interesting behaviors. [ABSTRACT FROM AUTHOR]

Broad new families of rational form variable separation solutions with two arbitrary lower-dimensional functions of the (2 + 1)-dimensional Broer-Kaup system with variable coefficients are derived by means of an improved mapping approach and a variable separation hypothesis. Based on the derived variable separation excitation, some new special types of localized solutions such as rouge wave, multidromion soliton, and soliton vanish phenomenon are revealed by selecting appropriate functions of the general variable separation solution. [ABSTRACT FROM AUTHOR]

A broad general variable separation solution with two arbitrary lower-dimensional functions of the (2+1)-dimensional Broer-Kaup (BK) equations was derived by means of a projective equation method and a variable separation hypothesis. Based on the derived variable separation excitation, some new special types of localized solutions such as oscillating solitons, instanton-like and cross-like fractal structures are revealed by selecting appropriate functions of the general variable separation solution. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the (3+1)-dimensional potential-YTSF equation is investigated. Exact solutions with three-wave form including periodic cross-kink wave, periodic two-solitary wave and breather type of two-solitary wave solutions are obtained using Hirota’s bilinear form and generalized three-wave approach with the aid of symbolic computation. Moreover, the properties for some new solutions are shown with some figures. [Copyright &y& Elsevier]

Abstract: Exact three-wave solutions including periodic cross-kink wave solutions, doubly periodic solitary wave solutions and breather type of two-solitary wave solutions for the (3+1)-dimensional Jimbo–Miwa equation are obtained using the generalized three-wave method. It is shown that the generalized three-wave method, with the help of symbolic computation, provides an effective and powerful mathematical tool for solving high-dimensional nonlinear evolution equations in mathematical physics. [Copyright &y& Elsevier]

Abstract: New exact solutions including homoclinic wave and periodic wave solutions for the 2D Ginzburg–Landau equation are obtained using the auxiliary function method and the -expansion method, respectively. The solutions are expressed by the hyperbolic functions and the trigonometric functions. There result shows that there exists a kink wave solution which tends to one and the same periodic wave solution as time tends to infinite. [ABSTRACT FROM AUTHOR]

Abstract: New exact solutions including the kink-shaped solutions, bell-shaped solutions, periodic solutions, singular soliton solutions and rational solution for the (2+1)-dimensional Sine-Gordon equation are obtained using the tanh method, the -expansion method and the auxiliary function method, respectively. [Copyright &y& Elsevier]

Abstract: In this paper, by using the generalized Riccati equation mapping method, and picking up its new solutions authors obtain abundant new exact solutions including kink solutions, periodic form solutions, soliton-like solutions and rational solutions to a -dimensional Jimbo–Miwa equation, respectively. [Copyright &y& Elsevier]

Abstract: In this short letter, new exact solutions including kink solutions, soliton-like solutions and periodic form solutions for a combined version of the potential KdV equation and the Schwarzian KdV equation are obtained using the generalized Riccati equation mapping method. [Copyright &y& Elsevier]

Abstract: New exact wave solutions including homoclinic wave, kink wave and soliton solutions for the 2D Ginzburg–Landau equation are obtained using the auxiliary function method, generalized Hirota method and the ansatz function technique under the certain constraint conditions of coefficients in equation, respectively. The result shows that there exists a kink-wave solution which tends to one and the same periodic wave solution as time tends to infinite. [Copyright &y& Elsevier]

Abstract: In this paper, we obtain a new class of exact cross kink-wave and periodic solitary-wave solutions for Jimbo–Miwa equation by using two-soliton method, bilinear method and transforming parameters into complex ones. Moreover, we investigate singular and non-singular phenomenons of solutions. In addition, we study the resonance and non-resonance interactions between periodic solitons and different line solitons. [Copyright &y& Elsevier]

The B-box proteins (BBXs) encode a family of zinc-finger transcription factors that regulate the plant circadian rhythm and early light morphogenesis. The double B-box (DBB) family is in the class of the B-box family, which contains two conserved B-box domains and lacks a CCT (CO, CO-like and TOC1) motif. In this study, the identity, classification, structures, conserved motifs, chromosomal location, cis elements, duplication events, and expression profiles of the PtrDBB genes were analyzed in the woody model plant Populus trichocarpa. Here, 12 PtrDBB genes (PtrDBB1–PtrDBB12) were identified and classified into four distinct groups, and all of them were homogeneously spread among eight out of seventeen poplar chromosomes. The collinearity analysis of the DBB family genes from P. trichocarpa and two other species (Z. mays and A. thaliana) indicated that segmental duplication gene pairs and high-level conservation were identified. The analysis of duplication events demonstrates an insight into the evolutionary patterns of DBB genes. The previously published transcriptome data showed that PtrDBB genes represented distinct expression patterns in various tissues at different stages. In addition, it was speculated that several PtrDBBs are involved in the responsive to drought stress, light/dark, and ABA and MeJA treatments, which implied that they might function in abiotic stress and phytohormone responses. In summary, our results contribute to the further understanding of the DBB family and provide a reference for potential functional studies of PtrDBB genes in P. trichocarpa. [ABSTRACT FROM AUTHOR]

Reintroduction programs seek to restore degraded populations and reverse biodiversity loss. To examine the hypothesis that gut symbionts could be used as an indicator of reintroduction success, we performed intensive metagenomic monitoring over 10 years to characterize the ecological succession and adaptive evolution of the gut symbionts of captive giant pandas reintroduced to the wild. We collected 63 fecal samples from 3 reintroduced individuals and 22 from 9 wild individuals and used 96 publicly available samples from another 3 captive individuals. By microbial composition analysis, we identified 3 community clusters of the gut microbiome (here termed enterotypes) with interenterotype succession that was closely related to the reintroduction process. Each of the 3 enterotypes was identified based on significant variation in the levels of 1 of 3 genera: Clostridium, Pseudomonas, and Escherichia. The enterotype of captive pandas was Escherichia. This enterotype was gradually replaced by the Clostridium enterotype during the wild‐training process, which in turn was replaced by the Pseudomonas enterotype that resembled the enterotype of wild pandas, an indicator of conversion to wildness and a successful reintroduction. We also isolated 1 strain of Pseudomonas protegens from the wild enterotype, a previously reported free‐living microbe, and found that its within‐host evolution contributed to host dietary adaptation in the wild. Monitoring gut microbial structure provides a novel, noninvasive tool that can be used as an indicator of successful reintroduction of a captive individual to the wild. [ABSTRACT FROM AUTHOR]

The interaction between vacancies and nitrogen atoms in fcc iron has been systematically studied by first-principles calculations. The interstitial N atoms bind strongly with vacancies into V n N m clusters, and each vacancy prefers only two N atoms that locate at the first nearest neighboring octahedral interstitial sites to the vacancy and align along the 〈1 0 0〉 directions. The number of N atoms is determined by the local lattice distortion evaluated by the expansion of atomic coordination polyhedrons with respect to the vacancy at the center. The most stable V 1 N 2 cluster can be considered as a structural unit for the cluster development. Moreover, in larger V n N m clusters with relatively high stability, the vacancies aggregate at the center and the N atoms are around the vacancies. Then, the effect of N solute on radiation swelling depending on the N concentration is discussed from a perspective of the cluster formation. The radiation swelling increases with the N concentration because the existence of N atoms can promote the vacancy aggregation and, hence, the nucleation and growth of voids. However, as the concentration further increases, N atoms will saturate the surfaces of vacancy clusters to form barrier layers, which can hinder the combination of the V n N m clusters and the void formation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Perillaldehyde could mitigate doxorubicin-induced cardiotoxicity in vitro and in vivo. • Notably, perillaldehyde significantly inhibited DOX-induced cardiac insufficiency, myocardial injury, oxidative stress, myocardial fibrosis, inflammatory response, and cardiomyocyte apoptosis. • Innovatively, the curative role of perillaldehyde on doxorubicin-induced cardiotoxicity is related to the inhibition of NHE1 phosphorylation and activation of PI3K/AKT phosphorylation. Doxorubicin (DOX), a broad-spectrum anti-tumor drug, has severe cardiotoxic side effects that limit its clinical application. Perillaldehyde (PAE) is the main component of volatile oil extracted from the stems and leaves of Herbaceous plant-perilla, which demonstrates antioxidant, anti-inflammatory, hypolipidemic, and other health functions. The present study aimed to explore the protective effect of perillaldehyde on DOX-induced cardiotoxicity in rats and to confirm its possible mechanism. The results showed that PAE could significantly improve cardiac function, alleviate myocardial fibrosis, and attenuate oxidative stress and inflammatory responses in DOX-induced cardiotoxicity in rats. Mechanistically, PAE could DOX-induced cardiotoxicity, which is related to its regulation of the PI3K/Akt signaling pathway and inhibition of NHE1 phosphorylation. Therefore, the finding demonstrates that perillaldehyde may be a promising cardioprotective agent for the prevention and treatment of cardiotoxicity caused by DOX. [ABSTRACT FROM AUTHOR]

The effects of [0 0 1] uniaxial strain on the energetics, stable structures, and structural evolution of vacancy clusters with different structure and orientation characteristics in copper have been studied by molecular statics simulation. The dependence of binding energies as functions of strain for different cluster types, including linear, planar, and body types, shows complicated behavior. The binding energies of both linear and planar clusters monotonously vary with the strain from −10% to 10%, while those of body clusters decrease with increasing both tensile and compressive strain. According to the variation of the binding energies, it has been suggested that the linear and planar clusters tend to align parallel (perpendicular) to the strain axis under tensile (compressive) strain. Moreover, both the {0 0 1} planar cluster and body cluster become the dominant types when the clusters grow under high strain. Then, a mechanism that the local structure around a vacancy cluster tends to approach the ideal lattice structure without defects and strain has been applied to explain the effects of the uniaxial strain on the relative stability of the vacancy clusters. This tendency is closely tied to the level of the atomic relaxation which can be measured by the average atomic displacement of the nearest-neighbor atoms surrounding the vacancy cluster. [ABSTRACT FROM AUTHOR]

This paper focuses on developing an agricultural droughty monitoring method in north Jiangsu province based on the measurements from the Moderate Resolution Imaging Spectroradiometer (MODIS). In order to build soil moisture estimation model, we collected gravimetric water content of soil at experimental sites in 2011, measured the soil moisture of the sites in 2012, and downloaded the 8-day MODIS reflectance and land surface temperature data from January to May in 2011 and 2012 in this study region. The gravimetric water content of soil included soil moisture at 10 cm depth and at 20 cm depth. The used MODIS data have some noise from atmospheric effects, and some data can not be acquired because of cloud. Therefore, a Savitzky-Golay (S-G) filter method was selected to remove NDVI and LST noise, and generate lost NDVI and LST. Then, the Temperature-Vegetation Dryness Index (TVDI) was calculated from the re-created NDVI and LST data. A correlation analysis between TVDI and soil moisture at 10 cm and 20 cm depth were conducted. The results showed that TVDI was more correlative with soil moisture at 10 cm depth compared to at 20 cm depth, and that soil moisture at 10 cm depth was highly correlative with soil moisture at 20 cm depth. Based on the TVDI and soil moisture data at 10 cm depth, an empirical model for soil moisture estimation was built and validated. In addition, an empirical model was also built to describe the relationship between soil moisture at 10 cm and 20 cm depth. Finally, the two models was utilized to estimate soil moisture at 20 cm depth in the area from MODIS data, and the estimated soil moisture was used to monitor field droughty status with a criterion about wheat field draughty evaluation. The results show that S-G filter method removes the MODIS data noise, and can be used to generate the lost data. The correlation analysis between soil moisture and TVDI shows that TVDI has higher correlation with soil moisture at 10 cm depth, and a linear model can be used to best-fit the relationship between TVDI and the soil moisture at 10 cm depth. The correlation analysis between soil moisture at 10 cm depth and at 20 cm depth shows that soil moisture at 20 cm depth has higher correlation with soil moisture at 10 cm depth, and a linear model can be used to best-fit the relationship between soil moisture at 10 cm depth and at 20 cm depth. The validation experiments show that the model obtains a high accuracy of soil moisture estimation with an r2 of 0.575 and a RMSE of 2.59 %. Using this model, soil moisture maps at 10 cm depth were obtained. The linear model describing the relationship between soil moisture at 10 cm and 20 cm depth was used to obtain soil moisture maps at 20 cm depth. Wheat field draught maps in north Jiangsu Province were obtained by the criterion about wheat field draughty evaluation. Validation experiments showed that the experiments showed the droughty monitoring method was promising in monitoring the droughty, which appeared in north Jiangsu province. [ABSTRACT FROM AUTHOR]