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1.
Neural networks show a progressive increase in complexity during the time course of evolution. From diffuse nerve nets in Cnidaria to modular, hierarchical systems in macaque and humans, there is a gradual shift from simple processes involving a limited amount of tasks and modalities to complex functional and behavioral processing integrating different kinds of information from highly specialized tissue. However, studies in a range of species suggest that fundamental similarities, in spatial and topological features as well as in developmental mechanisms for network formation, are retained across evolution. 'Small-world' topology and highly connected regions (hubs) are prevalent across the evolutionary scale, ensuring efficient processing and resilience to internal (e.g. lesions) and external (e.g. environment) changes. Furthermore, in most species, even the establishment of hubs, long-range connections linking distant components, and a modular organization, relies on similar mechanisms. In conclusion, evolutionary divergence leads to greater complexity while following essential developmental constraints.  相似文献   
2.
Unsteady magnetohydrodynamic heat and mass transfer analysis of hybrid nanoliquid flow over a stretching surface with chemical reaction, suction, slip effects, and thermal radiation is analyzed in this study. A combination of alumina (Al2O3) and titanium oxide (TiO2) nanoparticles are taken as hybrid nanoparticles and water is considered as the basefluid. Using the similarity transformation method, the governing equations are changed into a system of ordinary differential equations. These equations together with boundary conditions are numerically evaluated by using the Finite element method. The influence of various pertinent parameters on the profiles of fluids concentration, temperature, and velocity is calculated and the outcomes are plotted through graphs. The values of nondimensional rates of heat transfer, mass transfer, and velocity are also analyzed and the results are depicted in tables. Temperature sketches of hybrid nanoliquid intensified in both the steady and unsteady cases as the volume fraction of both nanoparticles rises.  相似文献   
3.
CeO2/CoPc nanocomposites were synthesized by simple chemical method. Thermal behavior of these nanocomposites was studied by thermogravimetric and differential thermal analysis. The as‐synthesized nanocomposite samples were characterized by various techniques. A decrease in band‐gap energy together with an improved absorption intensity of the composite material confirms the role of the cobalt phthalocyanine in the absorption properties of CeO2/CoPc composite. This study confirms structural modifications and extended spectral response of the synthesized CeO2/CoPc nanocomposites. The results demonstrate that CeO2/CoPc nanocomposite samples are promising materials for organic light‐emitting diodes, solar cells, and optoelectronic devices.  相似文献   
4.
In the present analysis, our aim is to investigate the mass and heat transport of silver (Ag)–ethylene glycol (EG) and copper (Cu)–EG-based nanofluids between two rotating stretchable disks under the convective boundary conditions. We have also incorporated Cattaneo–Christov heat flux, thermal radiation, and chemical reaction in the fluid flow. The system of coupled partial differential equations is transformed into ordinary differential equations by using similarity transformations. The finite element method has been accomplished to find numerical solutions to transformed equations. The behavior of radial and tangential velocity, temperature fields, and concentration fields influenced by the various parameters are sketched through graphs. The local skin friction coefficient, Nusselt number, and Sherwood number are also calculated for the pertinent parameters and displayed the results through tables. It is perceived that velocity sketches of both nanoliquids degenerate with larger values of thermal relaxation parameters. Also, the values local Nusselt number of both Ag–EG, and Cu–EG based Cattaneo–Christov nanofluid intensifies with improving values of stretching parameter at the lower disk, whereas, it impedes at the upper disk.  相似文献   
5.
The Buongiorno model Maxwell nanofluid flow, heat and mass transfer characteristics over a stretching sheet with a magnetic field, thermal radiation, and chemical reaction is numerically investigated in this analysis. This model incorporates the effects of Brownian motion and thermophoresis. The governing partial differential equations are transformed into a coupled nonlinear ordinary differential equation by using the similarity transformation technique. The resultant nonlinear differential equations are solved by using the Finite element method. The sketches of velocity, temperature and concentration with diverse values of magnetic field parameter (0.1 ≤ M ≤ 1.5), Deborah number (0.0 ≤ β ≤ 0.19), radiation parameter (0.1 ≤ R ≤ 0.7), Prandtl number (0.5 ≤ Pr ≤ 0.8), Brownian motion parameter (0.1 ≤ Nb ≤ 0.7), thermophoretic parameter (0.2 ≤ Nt ≤ 0.8), Chemical reaction parameter (1.0 ≤ Cr ≤ 2.5) and Lewis number (1.5 ≤ Le ≤ 3.0) have investigated and are depicted through plots. Moreover, the values of the Skin-friction coefficient, Nusselt number, and Sherwood numbers are also computed and are shown in tables. The sequels of this analysis reviewed that the values of Skin-friction coefficient and Sherwood number intensified with hiked values of Deborah number (β), whereas, the values of Nusselt number decelerate as values of (β) improves.  相似文献   
6.
A comprehensive study of the macrobenthic communities in the Kodungallur–Azhikode Estuary (KAE) was conducted during 2009–2011 period. A total of 18,846 organisms were collected, with 60% being malacostracans, followed by polychaetes (20%), molluscs (9%) and ‘others’ group (11%). A total of 79 species in 71 genera belonging to 49 families were identified, with 33 spp. being polychaetes, 26 spp. being malacostracans, 11 spp. being molluscs and 9 spp. being in the ‘others’ group. A single species of opportunistic amphipod (Americorophium triaeonyx) comprised more than 62.05% of the total numerical abundance of macrobenthos. The other dominant species were Obelia bidentata, Arcuatula senhousia, Cirolana fluviatilis, Prionospio cirrifera and Capitella sp. Canonical correspondence analysis (CCA) results indicated environmental parameters such as water column salinity, turbidity, sediment Eh, substratum type, chlorophyll‐a concentration, depth and organic matter in sediment were the significant factors influencing the distribution of macrobenthic species in the KAE. The present study provides baseline information for future KAE benthic studies.  相似文献   
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This study aims to synthesise and evaluate the acaricidal activity of nanoscale zinc oxide piperine formulation (NZPF) against Rhipicephalus microplus ticks. NZPF was prepared by using zinc oxide nanoparticles (ZnONPs) and piperine by employing encapsulation technique; characterised by UV spectroscopy, Fourier transformed infrared analysis, X‐ray diffraction, dynamic light scattering, zetapotential and scanning electron microscopy. Acaricidal activity of the NZPF on R. microplus was evaluated using larval packet test (LPT) and adult immersion test (AIT). LPT against R. microplus larvae showed an LC50 at 1 mg/l for NZPF followed by 2 and 3 mg/l for ZnONPs and piperine, respectively. AIT against R. microplus showed an LC50 at concentration of 3 mg/l for NZPF followed by 6 mg/l for ZnONPs and 7 mg/l for piperine. In both LPT and AIT, LC50 values of ZnONPs and NZPF were significantly lower compared to deltamethrin. NZPF showed significant ovulation inhibitory activity with lower IC50 and IC99 values compared to ZnONPs and piperine. NZPF has been proved to be the better alternative to routine chemical acaricides for control of tick infestation of cattle in the wake of acaricidal resistance, but safety issues need to be addressed before clinical application.Inspec keywords: molecular biophysics, pest control, ultraviolet spectra, X‐ray diffraction, zinc compounds, scanning electron microscopy, nanomedicine, agricultural engineering, agricultural safety, nanoparticles, light scattering, electrokinetic effects, encapsulation, Fourier transform infrared spectra, biotechnologyOther keywords: acaricidal activity, nanoscale zinc oxide piperine formulation, NZPF, Rhipicephalus microplus ticks, zinc oxide nanoparticles, ZnONP, LPT, adult immersion test, AIT, larval packet test, acaricidal resistance, UV spectroscopy, Fourier transformed infrared analysis, X‐ray diffraction, dynamic light scattering, zetapotential, scanning electron microscopy, ZnO  相似文献   
10.

Pure, porous titania nanowires (TiO2-pNW) are produced in bulk amount (~?250 kg/day, reaction time scale?<?1 min) using a unique solvo-plasma oxidation method utilizing microwave plasma with the potential of easy scale up. The prepared nanowire is found to be efficient towards both biotic disinfection and destruction of various abiotic contaminants in wastewaters. In terms of organic contaminants, the TiO2-pNW is tested for destruction of Rhodamine B (RhB) dye, tetracycline (TC) antibiotic, and diclofenac (DFC) and caffeine (CAF) drugs. In the case of biotic contaminants, the disinfection of E. coli bacteria is demonstrated. In all of the studies, the photocatalytic performance of anatase TiO2-pNW is compared to that of commercially available P25 nanoparticles (TiO2-P25), both in the presence and absence of ozone. The excellent photoactivity exhibited by TiO2-pNW is a result of low recombination rate of electron–hole pair owing to the spatial separation of electrons and holes within the photoexcited nanowires. Moreover, the scavenger experiments and experiments involving ozone reveal that electron transfer and/or presence of dissolved oxygen are the major limiting factors for both porous titania nanowires and P25 spherical powder under UV exposure with photocatalytic activity towards pollutant degradation.

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