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In this paper, we investigate the following chemotaxis–haptotaxis system (1) with nonlinear diffusion and signal production under homogenous Neumann boundary conditions in a bounded domain with smooth boundary. Under suitable conditions on the data we prove the following: (i) For 0 < γ ≤ 2 n , if α > γ − k + 1 and β > 1 − k , problem (1) admits a classical solution (u , v , w) which is globally bounded. (ii) For 2 n < γ ≤ 1 , if α > γ − k + 1 e + 1 and β > max { (n γ − 2) (n γ + 2 k − 2) 2 n − k + 1 , (n γ − 2) (γ + 1 e) n − k + 1 } or α > γ − k + 1 and β > max { (n γ − 2) (n γ + 2 k − 2) 2 n − k + 1 , (n γ − 2) (α + k − 1) n − k + 1 } , problem (1) admits a classical solution (u , v , w) which is globally bounded. [ABSTRACT FROM AUTHOR]

We consider the parabolic-elliptic chemotaxis system with the exponents depending on the spatial variableslogistic source and nonlinear signal production: $ u_{t} = \Delta u-\chi \nabla \cdot \left(u\nabla \upsilon \right) +f(x,u),(x,t)\in \Omega \times (0,T) $, $ 0 = \Delta \upsilon -\upsilon +u^{\gamma } $ in a bounded domain $ \Omega \subset \mathbb{R} ^{N} $ $ \left(N\geq 1\right) $ with smooth boundary, subject to nonnegative initial data and homogeneous Neumann boundary conditions, where $ \chi >0 $, $ \gamma \geq 1 $ and $ \frac{\partial }{\partial \nu } $ denotes the outward normal derivative on $ \partial \Omega $. The logistic function $ f $ fulfilling $ f(x,s)\leq \eta s-\mu s^{\alpha \left(x\right) +1} $, $ \eta \geq 0 $, $ \mu >0 $ for all $ s>0 $ with $ f(x,0)\geq 0 $ $ \forall x\in \Omega $, where $ \alpha :\Omega \rightarrow \left[ 1,\infty \right) $ is a measurable function. It is proved that if $ 1\leq \alpha \left(x\right) <\infty $ for all $ x\in \Omega $ such that $ ess\inf_{x\in \Omega }\alpha \left(x\right) >\gamma $ or$ ess\inf_{x\in \Omega }\alpha \left(x\right) = \gamma $ with $ \mu >\chi $, then there exists a nonnegative classical solution $ (u,\upsilon) $ that is global-in-time and bounded. In addition, under the particular conditions $ \gamma = 1 $ and $ f(x,s) = \mu \left(s-s^{\alpha \left(x\right) +1}\right) $, if $ \mu $ is sufficiently large, the global bounded solution $ (u,\upsilon) $ satisfies$ \begin{equation*} \left\Vert u\left(\cdot ,t\right) -1\right\Vert _{L^{\infty }\left(\Omega \right) }+\left\Vert \upsilon \left(\cdot ,t\right) -1\right\Vert _{L^{\infty }\left(\Omega \right) }\leq Ce^{-\frac{k}{N+2}t}\text{ } \end{equation*} $for all$ \ t>0 $ with $ k = \min \left\{ \frac{\chi ^{2}}{4},\frac{1}{2}\right\} $, $ C>0 $.The global-in-time existence and uniform-in-time boundedness of solutions are established under specific parameter conditions, which improves the known results. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the following chemotaxis–haptotaxis system (1) with nonlinear diffusion and signal production under homogenous Neumann boundary conditions in a bounded domain with smooth boundary. Under suitable conditions on the data we prove the following: (i) For 0<γ≤2n, if α>γ−k+1 and β>1−k, problem (1) admits a classical solution (u,v,w) which is globally bounded. (ii) For 2n<γ≤1, if α>γ−k+1e+1 and β>max{(nγ−2)(nγ+2k−2)2n−k+1,(nγ−2)(γ+1e)n−k+1} or α>γ−k+1 and β>max{(nγ−2)(nγ+2k−2)2n−k+1,(nγ−2)(α+k−1)n−k+1}, problem (1) admits a classical solution (u,v,w) which is globally bounded.

Human language is characterized by the integration of multiple signal modalities, including speech, facial and gestural signals. While language likely has deep evolutionary roots that are shared with some of our closest living relatives, studies of great ape communication have largely focused on each modality separately, thus hindering insights into the origins of its multimodal nature. Studying when multimodal signals emerge during great ape ontogeny can inform about both the proximate and ultimate mechanisms underlying their communication systems, shedding light on potential evolutionary continuity between humans and other apes. To this end, the current study investigated developmental patterns of multimodal signal production by 28 semiwild chimpanzees, Pan troglodytes , ranging in age from infancy to early adolescence. We examined the production of facial expressions, gestures and vocalizations across a range of behavioural contexts, both when produced separately and as part of multimodal signal combinations (henceforth multimodal). Overall, we found that while unimodal signals were produced consistently more often than multimodal combinations across all ages and contexts, the frequency of multimodal combinations increased significantly in older individuals and most within the aggression and play contexts, where the costs of signalling ambiguity may be higher. Furthermore, older individuals were more likely to produce a multimodal than a unimodal signal and, again, especially in aggressive contexts. Variation in production of individual signal modalities across ages and contexts are also presented and discussed. Overall, evidence that multimodality increases with age in chimpanzees is consistent with patterns of developing communicative complexity in human infancy, revealing apparent evolutionary continuity. Findings from this study contribute novel insights into the evolution and development of multimodality and highlight the importance of adopting a multimodal approach in the comparative study of primate communication. • Multimodality is a key feature of ape communication but is still poorly understood. • Chimpanzees already produce multimodal signal combinations from infancy. • Chimpanzee multimodal communication increased with age, similar to human children. • Multimodal combinations occurred more in contexts where cost of ambiguity was high. [ABSTRACT FROM AUTHOR]

Loop-mediated isothermal amplification (LAMP) is a thermostatic nucleic acid amplification technology that is widely used in the fields of clinical diagnosis and food safety detection. Centrifugal microfluidic chips are developed based on traditional microfluidic chips, using centrifugal force to achieve liquid flowing, mixing and reaction, eliminating the design of complex valves and pumps. The combination of LAMP and centrifugal microfluidic chips has great potential for rapid field nucleic acid detection. In this review, we discuss the design of a centrifugal microfluidic chip based on LAMP technology, including the chip fabrication, DNA extraction chamber, fluid control technology, common dye types in the reaction chamber, and the supporting detection device. It aims to provide some ideas and references for the further development and application of centrifugal microfluidic chip-based loop-mediated isothermal amplification in fast, on-site nucleic acid detection such as point-of-care tests and food safety. • Loop mediated isothermal amplification (LAMP) based centrifugal microfluidic chip system. • The construction of LAMP-based centrifugal microfluidic chips. • DNA extraction, fluid control, signal production and portable device of the system. • Commercialized LAMP-based centrifugal microfluidic chip. • Challenges and future perspective of the system. [ABSTRACT FROM AUTHOR]