Effects of Dispersal for a Logistic Growth Population in Random Environments

We study a stochastic logistic model with diffusion between two patches in this paper. Using the definition of stationary distribution, we discuss the effect of dispersal in detail. If the species are able to have nontrivial stationary distributions when the patches are isolated, then they continue to do so for small diffusion rates. In addition, we use some examples and numerical experiments to reflect that diffusions are capable of both stabilizing and destabilizing a given ecosystem

Equivariant Hopf Bifurcation in a Ring of Identical Cells with Delay

A kind of delay neural network with n elements is considered. By analyzing the distribution of the eigenvalues, a bifurcation set is given in an appropriate parameter space. Then by using the theory of equivariant Hopf bifurcations of ordinary differential equations due to Golubitsky et al. (1988) and delay differential equations due to Wu (1998), and combining the normal form theory of functional differential equations due to Faria and Magalhaes (1995), the equivariant Hopf bifurcation is completely analyzed

The Complete Parameters Analysis of the Asymptotic Behaviour of a Logistic Epidemic Model with Two Stochastic Perturbations

A simple model of the dynamics of an infectious disease, taking into account environmental variability in the form of Gaussian white noise in the disease transmission rate and the increase in mortality rate due to disease, has been investigated. The probability distribution for the proportion of infected animals, plus its mean, mode, and variance, is found explicitly

A facile synthesis of Co-doped g-C

Co-g-C3N4 catalyst was prepared by a simple calcination method using melamine and Co(NO3)3·6H2O as precursors. X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR) were used to characterize the prepared samples. The results indicated the Co species are successfully coordinated with g-C3N4. Degradation experiments showed that Rhodamine B can be degraded effectively at a very low cobalt doping concentration (0.2 wt %). The enhanced catalytic activity may result from the synergistic effect of visible light photocatalysis and sulfate radical based Co-g-C3N4/PMS system

Identification of a novel homozygous mutation, TMPRSS3: c.535G>A, in a Tibetan family with autosomal recessive non-syndromic hearing loss.

Different ethnic groups have distinct mutation spectrums associated with inheritable deafness. In order to identify the mutations responsible for congenital hearing loss in the Tibetan population, mutation screening for 98 deafness-related genes by microarray and massively parallel sequencing of captured target exons was conducted in one Tibetan family with familiar hearing loss. A homozygous mutation, TMPRSS3: c.535G>A, was identified in two affected brothers. Both parents are heterozygotes and an unaffected sister carries wild type alleles. The same mutation was not detected in 101 control Tibetan individuals. This missense mutation results in an amino acid change (p.Ala179Thr) at a highly conserved site in the scavenger receptor cysteine rich (SRCR) domain of the TMPRSS3 protein, which is essential for protein-protein interactions. Thus, this mutation likely affects the interactions of this transmembrane protein with extracellular molecules. According to our bioinformatic analyses, the TMPRSS3: c.535G>A mutation might damage protein function and lead to hearing loss. These data suggest that the homozygous mutation TMPRSS3: c.535G>A causes prelingual hearing loss in this Tibetan family. This is the first TMPRSS3 mutation found in the Chinese Tibetan population

Doping Ag in ZnO Nanorods to Improve the Performance of Related Enzymatic Glucose Sensors

In this paper, the performance of a zinc oxide (ZnO) nanorod-based enzymatic glucose sensor was enhanced with silver (Ag)-doped ZnO (ZnO-Ag) nanorods. The effect of the doped Ag on the surface morphologies, wettability, and electron transfer capability of the ZnO-Ag nanorods, as well as the catalytic character of glucose oxidase (GOx) and the performance of the glucose sensor was investigated. The results indicate that the doped Ag slightly weakens the surface roughness and hydrophilicity of the ZnO-Ag nanorods, but remarkably increases their electron transfer ability and enhances the catalytic character of GOx. Consequently, the combined effects of the above influencing factors lead to a notable improvement of the performance of the glucose sensor, that is, the sensitivity increases and the detection limit decreases. The optimal amount of the doped Ag is determined to be 2 mM, and the corresponding glucose sensor exhibits a sensitivity of 3.85 μA/(mM·cm2), detection limit of 1.5 μM, linear range of 1.5 × 10−3–6.5 mM, and Michaelis-Menten constant of 3.87 mM. Moreover, the glucose sensor shows excellent selectivity to urea, ascorbic acid, and uric acid, in addition to displaying good storage stability. These results demonstrate that ZnO-Ag nanorods are promising matrix materials for the construction of other enzymatic biosensors

The Crystallization Behavior of TiO2-CaO-SiO2-Al2O3-MgO Pentabasic Slag with a Basicity of 1.1–1.4

The utilization of titanium-containing blast furnace slag has been an unsolved problem for a long time. Failure to make effective use of the slag, which is caused by a high TiO2 content within it, not only results in a waste of resources, especially titanium, but also increases environmental risk. The key to address the problem is the enrichment and extraction of TiO2 from the slag first. Therefore, in order to study the enrichment of titanium, the crystallization behavior of TiO2-CaO-SiO2-Al2O3-MgO pentabasic slag, the main compositions of titanium-containing blast furnace slag, within the basicity range of 1.1–1.4 was investigated theoretically and experimentally. Thermodynamic calculation shows that perovskite is the main titanium-containing phase and titanium can be enriched in perovskite. By decreasing the temperature, perovskite precipitates at first. Additionally, with the increase of basicity, perovskite precipitation temperature increases continuously, and its amount of precipitation almost does not change, while the amounts of other phases change obviously. The experimental results demonstrate similar results except for the amount of perovskite (with the increase of basicity, perovskite precipitation amount increases slightly), caused by kinetic reason. In addition, the morphology of the slag at different scales was observed. The surface of the cooled slag is granular, vein-like, and irregular, multilaterally shaped from outside to inside. The crystal is dendritic with a spine-like trunk, and the edge is blade-like. In terms of the structure of the crystal, the inner part of it is perovskite, and the outer part is covered with a layer of other phases with spinel inlaying it. Finally, the precipitated mechanism is proposed as well