AOBLMOA: A Hybrid Biomimetic Optimization Algorithm for Numerical Optimization and Engineering Design Problems.

The Mayfly Optimization Algorithm (MOA), as a new biomimetic metaheuristic algorithm with superior algorithm framework and optimization methods, plays a remarkable role in solving optimization problems. However, there are still shortcomings of convergence speed and local optimization in this algorithm. This paper proposes a metaheuristic algorithm for continuous and constrained global optimization problems, which combines the MOA, the Aquila Optimizer (AO), and the opposition-based learning (OBL) strategy, called AOBLMOA, to overcome the shortcomings of the MOA. The proposed algorithm first fuses the high soar with vertical stoop method and the low flight with slow descent attack method in the AO into the position movement process of the male mayfly population in the MOA. Then, it incorporates the contour flight with short glide attack and the walk and grab prey methods in the AO into the positional movement of female mayfly populations in the MOA. Finally, it replaces the gene mutation behavior of offspring mayfly populations in the MOA with the OBL strategy. To verify the optimization ability of the new algorithm, we conduct three sets of experiments. In the first experiment, we apply AOBLMOA to 19 benchmark functions to test whether it is the optimal strategy among multiple combined strategies. In the second experiment, we test AOBLMOA by using 30 CEC2017 numerical optimization problems and compare it with state-of-the-art metaheuristic algorithms. In the third experiment, 10 CEC2020 real-world constrained optimization problems are used to demonstrate the applicability of AOBLMOA to engineering design problems. The experimental results show that the proposed AOBLMOA is effective and superior and is feasible in numerical optimization problems and engineering design problems.

Regulation of insulin secretion by the post-translational modifications.

Post-translational modification (PTM) has a significant impact on cellular signaling and function regulation. In pancreatic ß cells, PTMs are involved in insulin secretion, cell development, and viability. The dysregulation of PTM in ß cells is clinically associated with the development of diabetes mellitus. Here, we summarized current findings on major PTMs occurring in ß cells and their roles in insulin secretion. Our work provides comprehensive insight into understanding the mechanisms of insulin secretion and potential therapeutic targets for diabetes from the perspective of protein PTMs.

Chemical Weathering and CO2 Consumption Inferred from Riverine Water Chemistry in the Xi River Drainage, South China.

Hydrochemistry and strontium isotope data were analysed in water samples from the Xi River Drainage system to reveal the spatial and seasonal variations in chemical weathering, associated CO2 consumption fluxes, and their control factors. The main ions were Ca2+, Mg2+, and HCO3-, which are characteristic of a drainage system on carbonate-dominated bedrock. The dissolved loads were derived from four major end-member reservoirs: silicate, limestone, dolomite, and atmosphere. The silicate weathering rates (SWRs) increased downstream from 0.03 t/km2/year to 2.37 t/km2/year. The carbonate weathering rates (CWRs) increased from 2.14 t/km2/year in the upper reaches, to 32.65 t/km2/year in the middle reaches, and then decreased to 23.20 t/km2/year in the lower reaches. The SWR values were 281.38 and 113.65 kg/km2/month during the high- and low-water periods, respectively. The CWR values were 2456.72 and 1409.32 kg/km2/month, respectively. The limestone weathering rates were 2042.74 and 1222.38 kg/km2/month, respectively. The dolomite weathering rates were 413.98 and 186.94 kg/km2/month, respectively. Spatial and seasonal variations in chemical weathering were controlled mainly by lithology, vegetation, and climate (temperature, water discharge, and precipitation). The CO2 consumption flux by chemical weathering was estimated at 189.79 × 109 mol/year, with 156.37 × 109 and 33.42 × 109 mol/year for carbonate and silicate weathering, respectively. The CO2 fluxes by chemical weathering are substantially influenced by sulfuric acid in the system. The CO2 flux produced by sulfuric acid weathering was estimated at 30.00 × 109 mol/year in the basin. Therefore, the Xi River Basin is a CO2 sink with a net consumption of CO2 flux of 3.42 × 109 mol/year.

Spatiotemporal Evolution and Regional Differences in the Production-Living-Ecological Space of the Urban Agglomeration in the Middle Reaches of the Yangtze River.

The urban agglomeration in the middle reaches of the Yangtze River, which is the second largest urban agglomeration in China, represents a typical land space range of ecological vulnerability in China. Large differences occur in economic development mode between resource- and non-resource-based cities in this basin area. Accurate identification of the evolution and regional differences in the production-living-ecological space (PLES) is very important in order to elucidate the development and utilization of land space in the region. At present, relevant research has largely focused on the classification and determination of PLES temporal and spatial patterns. Temporal and spatial pattern research has mainly considered a single scale of administrative division, whereas fewer studies have analyzed the temporal and spatial patterns and regional differences in the PLES in ecologically fragile natural watersheds. Therefore, based on PLES classification, the regional differences in the PLES between two types of cities in the basin are measured via the Theil index and exploratory spatial data analysis (ESDA). First, the ecological space (ES) of these two types of cities in the urban agglomeration in the middle reaches of the Yangtze River is compressed by the production space (PS) and living space (LS), in which the ES of resource-based cities is compressed for a longer period, and the phenomenon involving PS compression by the LS and ES mainly occurs in non-resource-based cities within the urban agglomeration in the middle reaches of the Yangtze River. Second, the PLES of these two types of cities exhibits the characteristics of spatial aggregation, and high- and low-density areas of the PLES remain relatively stable. Third, the regional differences in the PLES of the urban agglomeration in the middle reaches of the Yangtze River mainly originate from intraregional differences. The PLES of these two types of cities in the urban agglomeration in the middle reaches of the Yangtze River is more sensitive to changes in economic development than to those in the population distribution.

Protein adsorption-dependent electro-kinetic pore flow: modeling of ion-exchange electrochromatography with an oscillatory transverse electric field.

Electro-kinetic acceleration of protein mass transfer was studied by dynamic chromatographic experiments and computer simulations on IEC with an oscillatory transverse electric field (EF) perpendicular to the mobile-phase flow (pIEEC). The breakthrough behavior of BSA was investigated at different electric current densities. A two-dimensional mathematical model has been established to describe the electro-kinetic convection-diffusion behavior of protein adsorption in a single adsorbent particle. The equation was coupled with the axial dispersion model to simulate the dynamic adsorption process in the pIEEC. The model parameters were determined by independent experiments or calculations. It was found that protein adsorption led to an exponential decrease of intraparticle electro-kinetic flow with increasing protein adsorption. Taking this effect into consideration, the model calculations could well describe dynamic breakthrough curves. Moreover, protein distribution in adsorbents was observed to present excursion along the periodical oscillatory EF direction. At the beginning of pIEEC, intraparticle convection caused by the EF contributed more to the enhancement of dynamic binding capacity. Finally, it was confirmed that both the EOF and electrophoresis contributed to the acceleration of mass transfer.