In this article, a finite volume element algorithm is presented and discussed for the numerical solutions of a time-fractional nonlinear fourth-order diffusion equation with time delay. By choosing the second-order sp...
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In this article, a finite volume element algorithm is presented and discussed for the numerical solutions of a time-fractional nonlinear fourth-order diffusion equation with time delay. By choosing the second-order spatial derivative of the original unknown as an additional variable, the fourth-order problem is transformed into a second-order system. Then the fully discrete finite volume element scheme is formulated by using L1approximation for temporal Caputo derivative and finite volume element method in spatial direction. The unique solvability and stable result of the proposed scheme are proved. A priori estimate of L2-norm with optimal order of convergence O(h2+τ2−α)where τand hare time step length and space mesh parameter, respectively, is obtained. The efficiency of the scheme is supported by some numerical experiments.
Fractional-order time-delay differential equations can describe many complex physical phenomena with memory or delay effects, which are widely used in the fields of cell biology, control systems, signal processing, et...
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Fractional-order time-delay differential equations can describe many complex physical phenomena with memory or delay effects, which are widely used in the fields of cell biology, control systems, signal processing, etc. Therefore, it is of great significance to study fractional-order time-delay differential equations. In this paper, we discuss a finite volume element method for a class of fractional-order neutral time-delay differential equations. By introducing an intermediate variable, the fourth-order problem is transformed into a system of equations consisting of two second-order partial differential equations. The L1 formula is used to approximate the time fractional order derivative terms, and the finite volume element method is used in space. A fully discrete format of the equations is established, and we prove the existence, uniqueness, convergence and stability of the solution. Finally, the validity of the format is verified by numerical examples.
Thin walls of an AZ91 magnesium alloy with fine equiaxed grains were fabricated via cold arc-based wire arc additive manufacturing(CA-WAAM),and the droplet transfer behaviours,microstructures,and mechanical properties...
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Thin walls of an AZ91 magnesium alloy with fine equiaxed grains were fabricated via cold arc-based wire arc additive manufacturing(CA-WAAM),and the droplet transfer behaviours,microstructures,and mechanical properties were *** results showed that the cold arc process reduced splashing at the moment of liquid bridge breakage and effectively shortened the droplet transfer *** microstructures of the deposited samples exhibited layered characteristics with alternating distributions of coarse and fine *** layer-by-layer deposition,the β-phase precipitated and grew preferentially along grain boundaries,while the fineη-Al_(8)Mn_(5)phase was dispersed in the α-Mg *** mechanical properties of the CA-WAAM deposited sample showed isotropic *** ultimate tensile strength and elongation in the building direction(BD)were 282.7 MPa and 14.2%,*** microhardness values of the deposited parts were relatively uniform,with an average value of HV 69.6.
Chitin is an abundant natural biopolymer that plays a crucial role in insect growth and development as a fundamental structural component of the *** membrane-integralβ-glycosyltransferase,chitin synthase,has been ide...
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Chitin is an abundant natural biopolymer that plays a crucial role in insect growth and development as a fundamental structural component of the *** membrane-integralβ-glycosyltransferase,chitin synthase,has been identified as the central component in chitin ***,the precise roles of other proteins in facilitating chitin synthase in chitin biosynthesis remain *** this study,we employed split-ubiquitin membrane yeast two-hybrid(MYTH)and pull-down assays to demonstrate the physical interaction between Twinstar(Tsr),a small molecular protein in the actin-depolymerizing factor ADF/Cofilin protein family,and chitin synthase Krotzkopf verkehrt(Kkv)in Drosophila melanogaster in *** RNA interference(RNAi)-mediated global knockdown of Tsr in *** resulted in larval ***,targeted suppression of Tsr in the tracheal and epidermal tissues also led to larval mortality,while knocking down Tsr in the wing tissues led to wrinkled ***,silencing Tsr not only reduced the chitin content in the first longitudinal vein of the wings but also led to the absence of the chitin lamellar *** validate the functional conservation of Tsr in other insect orders,the two agricultural pests Ostrinia furnacalis and Tribolium castaneum,representing lepidoptera and coleoptera insects,respectively,were *** experiments targeting the Drosophila Tsr orthologues OfTsr in *** and TcTsr in *** produced abnormal larvae during molting or pupation in *** and lethality in *** findings not only improve ourknowledge of the chitin biosynthesis machinery in insect cuticles but also provide new potential targets for the control of major agricultural pests.
It is fundamental and useful to investigate how deep learning forecasting models(DLMs)perform compared to operational oceanography forecast systems(OFSs).However,few studies have intercompared their performances using...
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It is fundamental and useful to investigate how deep learning forecasting models(DLMs)perform compared to operational oceanography forecast systems(OFSs).However,few studies have intercompared their performances using an identical *** this study,three physically reasonable DLMs are implemented for the forecasting of the sea surface temperature(SST),sea level anomaly(SLA),and sea surface velocity in the South China *** DLMs are validated against both the testing dataset and the“OceanPredict”Class 4 *** show that the DLMs'RMSEs against the latter increase by 44%,245%,302%,and 109%for SST,SLA,current speed,and direction,respectively,compared to those against the ***,different references have significant influences on the validation,and it is necessary to use an identical and independent reference to intercompare the DLMs and *** the Class 4 dataset,the DLMs present significantly better performance for SLA than the OFSs,and slightly better performances for other *** error patterns of the DLMs and OFSs show a high degree of similarity,which is reasonable from the viewpoint of predictability,facilitating further applications of the *** extreme events,the DLMs and OFSs both present large but similar forecast errors for SLA and current speed,while the DLMs are likely to give larger errors for SST and current *** study provides an evaluation of the forecast skills of commonly used DLMs and provides an example to objectively intercompare different DLMs.
Single-shot ultrafast compressed imaging(UCI) is an effective tool for studying ultrafast dynamics in physics, chemistry,or material science because of its excellent high frame rate and large frame number. However, th...
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Single-shot ultrafast compressed imaging(UCI) is an effective tool for studying ultrafast dynamics in physics, chemistry,or material science because of its excellent high frame rate and large frame number. However, the random code(Rcode) used in traditional UCI will lead to low-frequency noise covering high-frequency information due to its uneven sampling interval, which is a great challenge in the fidelity of large-frame reconstruction. Here, a high-frequency enhanced compressed active photography(H-CAP) is proposed. By uniformizing the sampling interval of R-code, H-CAP capture the ultrafast process with a random uniform sampling mode. This sampling mode makes the high-frequency sampling energy dominant, which greatly suppresses the low-frequency noise blurring caused by R-code and achieves high-frequency information of image enhanced. The superior dynamic performance and large-frame reconstruction ability of H-CAP are verified by imaging optical self-focusing effect and static object, respectively. We applied H-CAP to the spatial-temporal characterization of double-pulse induced silicon surface ablation dynamics, which is performed within 220 frames in a single-shot of 300 ps. H-CAP provides a high-fidelity imaging method for observing ultrafast unrepeatable dynamic processes with large frames.
The macrophage-mediated inflammatory response is crucial for the recovery of skeletal muscle following ***,macrophage-based therapeutic targets need to be explored for ischemic *** the current study,we found that the ...
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The macrophage-mediated inflammatory response is crucial for the recovery of skeletal muscle following ***,macrophage-based therapeutic targets need to be explored for ischemic *** the current study,we found that the mRNA levels of scavenger receptor A1(Sr-a1)were elevated in patients with critical limb ischemia,based on an analysis of the Gene Expression Omnibus *** then investigated the role and underlying mechanisms of macrophage SR-A1 in a mouse hindlimb ischemia(HLI)*** with the Sr-a1^(fl/fl)mice,the Lyz^(Cre+)/Sr-a1^(flox/flox)(Sr-a1~(ΔMΦ))mice showed significantly reduced laser Doppler blood flow in the ischemic limb on day seven after ***,histological analysis revealed that the ischemic limb of the Sr-a1~(ΔMΦ)mice exhibited more severe and prolonged necrotic morphology,inflammation,fibrosis,decreased vessel density,and delayed regeneration than that of the control Sr-a1~(fl/fl)***,restoring wild-type myeloid cells to the Sr-a1 knockout mice effectively improved the Doppler perfusion in the ischemic limb and mitigated skeletal muscle damage seven days after *** with these in vivo findings,co-cultivating macrophages with the mouse myoblast cell line C2C12 revealed that the Sr-a1^(-/-)bone marrow macrophages significantly inhibited myoblast differentiation in ***,SR-A1 enhanced the skeletal muscle regeneration in response to HLI by inhibiting oncostatin M production via suppression of the NF-κB signaling *** findings indicate that SR-A1 may be a promising candidate protein to improve tissue repair and regeneration in peripheral ischemic arterial disease.
Introducing the inherent genetic diversity of wild species into cultivars has become one of the hot topics in crop genetic breeding and genetic resource research. Fiber-and seed-related traits, which are critical to t...
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Introducing the inherent genetic diversity of wild species into cultivars has become one of the hot topics in crop genetic breeding and genetic resource research. Fiber-and seed-related traits, which are critical to the global economy and people's livelihoods, are the principal focus of cotton breeding. Here, the wild cotton species Gossypium tomentosum was used to broaden the genetic basis of G. hirsutum and identify QTLs for fiber-and seed-related traits. A population of 559 chromosome segment substitution lines(CSSLs) was established with various chromosome segments from G. tomentosum in a G. hirsutum cultivar background. Totals of 72, 89, and 76 QTLs were identified for three yield traits, five fiber quality traits, and six cottonseed nutrient quality traits, *** alleles of 104 QTLs were contributed by G. tomentosum. Sixty-four QTLs were identified in two or more environments, and candidate genes for three of them were further identified. The results of this study contribute to further studies on the genetic basis of the morphogenesis of these economic traits, and indicate the great breeding potential of G. tomentosum for improving the fiber-and seed-related traits in G. hirsutum.
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