One-dimensional spatio-temporal patterns in the CIMA reaction

Spatial patterns in biotic reactions of forest trees (secondary growth, defoliation, nutrition) in Germany and their associations with conditions and changes in forest soils and with other environmental variables were investigated. The study aimed to identify areas at risk and risk factors. Growth ring widths and defoliation indicated drought stress as main risk factor. High annual mean temperature deviations of approximately 1.5 °C from the long-term mean (1961–1990), particularly in combination with high negative precipitation deviations, were associated with increased defoliation in all four main tree species. Defoliation development types that showed clear large-scale spatial distribution patterns were identified for all species. The defoliation development types were in good accordance with the landscape regions of Germany. Weather conditions, in particular deviations of temperature and precipitation from the long-term mean, explained a large proportion of differences among defoliation development types. South-western Germany was the region at highest risk for defoliation in recent years. This finding was mainly attributed to severe drought stress in this region in the previous years. Nutrition types did not display a strong spatial pattern. In regions affected by chronic high N deposition or where intensive liming has been conducted, antagonistic effects of K with other nutrients ( $$ {\mathrm{NH}}_4^{+} $$ , Ca) probably played a role in frequently observed deficient nutrition of forest trees with K and also in defoliation. Mitigation of climate change should have top priority. Environmental policy and forest management should further aim to reduce stress factors originating from air pollution and nutrient deficiencies in order to facilitate the regenerative capability of forest trees and adaption to climate change.

On stability and uniqueness of stationary one-dimensional patterns in the Belousov-Zhabotinsky reaction

The generalized fractional reaction–diffusion equations which exist in the form of noninteger order partial differential equations have now found wide application for illustrating important and useful physical phenomena, such as subdiffusive and superdiffusive scenarios. The space fractional derivatives are defined in the Riesz sense on the intervals $$0<\alpha <1$$ and $$1<\alpha \le 2$$ . We propose robust numerical techniques, such as a spectral representation of the fractional Laplacian operator in conjunction with the exponential time differencing method, and present the equivalent relationship between the Riesz fractional derivative and fractional Laplacian operator. We apply these techniques to numerically solve a range of chaotic processes, such as the Chua’s equations, Rossler system, Lorenz and Lorenz-type systems. Simulation results revealed various complex and spatiotemporal chaos, spiral chaos, intermittent chaos and spots patterns in two-dimensional space fractional reaction–diffusion problems.

初回部位におけるツベルクリン反応の時間的経過に関する研究 : 第3編 初回部位におけるツベルクリン反応の時間的経過と血中抗体との関係

同一局所反復施行によるツベルクリン反応の促進に関する研究 : 第8報 反応の時間的経過に関する研究(3) : 結核学童と健康学童について同一局所に反復注射した場合のツ反応の時間的経過

Rotating spiral waves organize excitation in various biological, physical, and chemical systems. They underpin a variety of important phenomena, such as cardiac arrhythmias, morphogenesis processes, and spatial patterns in chemical reactions. Important insights into spiral wave dynamics have been obtained from theoretical studies of the reaction-diffusion (RD) partial differential equations. However, most of these studies have ignored the fact that spiral wave rotation is often accompanied by substantial deformations of the medium. Here, we show that joint consideration of the RD equations with the equations of continuum mechanics for tissue deformations (RD-mechanics systems), yield important effects on spiral wave dynamics. We show that deformation can induce the breakup of spiral waves into complex spatiotemporal patterns. We also show that mechanics leads to spiral wave drift throughout the medium approaching dynamical attractors, which are determined by the parameters of the model and the size of the medium. We study mechanisms of these effects and discuss their applicability to the theory of cardiac arrhythmias. Overall, we demonstrate the importance of RD-mechanics systems for mathematics applied to life sciences.

Spatial patterns of precipitation reaction

Worldwide, mineral exploration is suffering from rising capital costs, due to the depletion of readily recoverable reserves and the need to discover and assess more inaccessible or geologically complex deposits. For gold exploration, this problem is particularly acute. We propose an innovative approach to mineral exploration and orebody characterisation, based on the analysis of geological core data as a spatial dynamical system, using the mathematical tools of dynamical system analysis. This approach is highly relevant for orogenic gold deposits, which-in contrast to systems formed at chemical equilibrium-exhibit many features of nonlinear dynamical systems, including episodic fluctuations on various length and time scales. Feedback relationships between thermo-chemical and deformation processes produce recurrent fluid temperatures and pressures and the deposition of vein-filling minerals such as pyrite and gold. We therefore relax the typical assumption of chemical equilibrium and analyse the underlying processes as aseismic, non-adiabatic, and inherent to a hydrothermal, nonlinear dynamical open-flow chemical reactor. These processes are approximated using the Gray-Scott model of reaction-diffusion as a complex toy system, which captures some of the features of the underlying mineralisation processes, including the spatiotemporal Turing patterns of unsteady chemical reactions. By use of this analysis, we demonstrate the capability of recurrence plots, recurrence power spectra, and recurrence time probabilities to detect underlying unstable periodic orbits as one sign of deterministic dynamics and their robustness for the analysis of data contaminated by noise. Recurrence plot based quantification is then applied to three mineral concentrations in the core data from the Sunrise Dam gold deposit in the Yilgarn region of Western Australia. Using a moving window, we reveal the episodic recurring low-dimensional dynamic structures and the period doubling route to instability with depth, embedded in and originating from higher-dimensional processes of the complex mineralisation system.

EPT: An R package for ensemble patch transform

The purpose of this study is to explore and illustrate the potential of exposed roots to reconstruct larger-scale landslide activity and thus to complement tree-ring data gathered from stems to reconstruct spatio-temporal patterns of landslide reactivation. Work was undertaken in a forested area of the Davids-Bas landslide, Barcelonnette (Southeastern French Alps) and based on growth disturbances (GD) from 48 stems and on anatomical changes (decrease of cell lumina) in 20 exposed root sections of heavily affected Mountain pine (Pinus uncinata Mill. ex Mirb.) trees growing on the scarps and upon the landslide body. A total of 95 GD and 20 anatomical changes were identified in the samples pointing to 7 movements of the landslide body since AD 1977. The study demonstrates that reconstructions of landslide reactivations obtained from exposed roots samples are not significantly different from those gathered from stems, but that the inclusion of exposed roots permits realization of frequency maps in sectors which could not be documented with classic dendrogeomorphic approaches focusing on tree-ring records from stems (scars, cracks). In addition, and even more importantly, the inclusion of exposed roots allowed assessment of the geomorphic evolution of the landslide at the local scale and to detect precursor signals of major reactivations in the form of crack widening before the main movement was registered in the tree stems. In that sense, the combined approach presented in this paper can be considered as a valuable tool for land-use planners and emergency cells in charge of forecasting future events and in protecting people and their assets from the negative effects of landslides.

Stability and bifurcation analysis of a reaction–diffusion equation with spatio-temporal delay

Three-dimensional CFD simulation of pattern formation in a shallow packed-bed reactor for oxidative coupling of methane

This study examines the job satisfaction dynamics of entrepreneurs. Using the Household Income and Labour Dynamic in Australia (HILDA) survey, we evaluate the temporal pattern of anticipation, reaction, and adaptation in job satisfaction occurring before, during, and after the transition into self-employment. Results vary across the different domains of job satisfaction: while entrepreneurship entry induces a short-term boost in overall job satisfaction and satisfaction with the work itself, it has a long-lasting negative impact on satisfaction with income and job security. Further, entrepreneurs exhibit positive adaption to balancing work, non-work commitments, and leisure time. No significant gender differences were identified.KeywordsLags and leadsEntrepreneurshipHedonic treadmillHedonic adaptationJob satisfactionHILDAPanel data analysisGender analysis

To study regional and temporal pattern of glial and neuronal reaction to induction of kaolin hydrocephalus in adult rats. Enzyme- and immunohistochemistry was performed in 20 adult rats with kaolin-hydrocephalus after 2, 4, 6 and 8 weeks to glial glutamatergic transmission activity (GLDH) and neuronal nitrous oxide synthetic activity (nNOS). Also, glial fibrillary acidic protein (GFAP), 68 kd neurofilament protein (NF68) and synaptophysin (SYN38) and basic fibroblastic growth-factor (bFGF) were stained. Results were quantified by imaging analysis (SCION IMAGE) and expressed as relative immunopositive area. After 2 weeks, nNos-activity increased in cortical and hippocampal neurones (CA1 and CA3) and GLDH-activity also showed increases, most significant in periventricular white matter (25.7 +/- 3.8 vs. 15.5 +/- 4.9; p < 0.001) and hippocampus (p < 0.01). After 4 or 6 weeks, global cortical GLDH-activity showed further marked increases (25.7 +/- 3.9 vs. 11.3 +/- 1.5; p < 0.05), while sustained structural changes have occurred: GFAP decreased in periventricular (3.3 +/- 0.5 vs. 6.3 +/- 1.2; p < 0.01), hippocampal and cortical astrocytes (0.9 +/- 0.34 vs. 5.0 +/- 0.7%; p < 0.01), whereas NF68 in cortical efferent neurones increased (6.5 +/- 1.5% vs. 4.7 +/- 0.1; p < 0.01) followed by a decrease in cortical and hippocampal (CA1) SYN 38 (p < 0.05). Acute glial and neuronal reactions were almost functional and in chronic stages sustained structural changes predominated. Since neuronal reactions were pronounced in selective vulnerable areas glial reaction was not restricted to periventricular astrocytes.

Studies on the Temporal Patterns of Tuberculin Reaction in the New Site. : Part 2.Effects of the Repitation of the Tuberculin Reaction to the Temporal Pattern of the Tuberculin Reaction in the New Site