Phylogeography of the South China Field Mouse (Apodemus draco) on the Southeastern Tibetan Plateau Reveals High Genetic Diversity and Glacial Refugia

The southeastern margin of the Tibetan Plateau (SEMTP) is a particularly interesting region due to its topographic complexity and unique geologic history, but phylogeographic studies that focus on this region are rare. In this study, we investigated the phylogeography of the South China field mouse, Apodemus draco, in order to assess the role of geologic and climatic events on the Tibetan Plateau in shaping its genetic structure. We sequenced mitochondrial cytochrome b (cyt b) sequences in 103 individuals from 47 sampling sites. In addition, 23 cyt b sequences were collected from GenBank for analyses. Phylogenetic, demographic and landscape genetic methods were conducted. Seventy-six cyt b haplotypes were found and the genetic diversity was extremely high (π = 0.0368; h = 0.989). Five major evolutionary clades, based on geographic locations, were identified. Demographic analyses implied subclade 1A and subclade 1B experienced population expansions at about 0.052-0.013 Mya and 0.014-0.004 Mya, respectively. The divergence time analysis showed that the split between clade 1 and clade 2 occurred 0.26 Mya, which fell into the extensive glacial period (EGP, 0.5-0.17 Mya). The divergence times of other main clades (2.20-0.55 Mya) were congruent with the periods of the Qingzang Movement (3.6-1.7 Mya) and the Kun-Huang Movement (1.2-0.6 Mya), which were known as the most intense uplift events in the Tibetan Plateau. Our study supported the hypothesis that the SEMTP was a large late Pleistocene refugium, and further inferred that the Gongga Mountain Region and Hongya County were glacial refugia for A. draco in clade 1. We hypothesize that the evolutionary history of A. draco in the SEMTP primarily occurred in two stages. First, an initial divergence would have been shaped by uplift events of the Tibetan Plateau. Then, major glaciations in the Pleistocene added complexity to its demographic history and genetic structure

The driver design for N

In this paper, the driver circuit for N2O gas detection system based on tunable interband cascade laser (ICL) is developed. Considering the influence of power supply stability on the digital-analog hybrid drive circuit of tunable diode laser absorption spectroscopy (TDALS), the high-efficiency TPS5430 is used to design the positive and negative power supply circuit. The large electrolytic capacitor + post-stage LC filter combination filter is used to effectively filter out high and low frequency ripple and switching noise. The use of thick high current trace + via + multilayer printed circuit board (PCB) design makes the line temperature rise smaller, more stable and durable, and uses high frequency shielding inductance to effectively reduce radiation interference to ensure the stability of the drive. The STM32F407, a highperformance microcontroller based on the ARM Cortex-M4 core, is used as the master control chip and generates a sawtooth scanning signal. The direct digital synthesizer (DDS) chip ICL8038 is used to generate a sinusoidal modulated signal of a specific frequency. The two signals are superimposed by a reverse addition circuit, and the laser drive signal is generated by a developed positive feedback balanced voltagecurrent conversion circuit. Experimental results show that the driver circuit can well meet the drive development requirements of N2O gas detection systems based on tunable interband cascade laser

Antibacterial Performance of a Mussel-Inspired Polydopamine-Treated Ag/Graphene Nanocomposite Material

Graphene-based nanocomposites have attracted tremendous attention in recent years. In this study, a facile yet effective approach was developed to synthesize reduced graphene oxide and an Ag–graphene nanocomposite. The basic strategy involved in the preparation of reduced graphene oxide includes reducing graphene oxide with dopamine, followed by in situ syntheses of the Ag-PDA-reducing graphene oxide (RGO) nanocomposite through adding AgNO3 solution and a small amount of dopamine. The nanocomposite was characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD), FTIR spectra, Raman spectra, ultraviolet-visible (UV-vis), and X-ray photoelectron spectroscopy (XPS), results indicated that a uniform PDA film is formed on the surface of the GO and GO is successfully reduced. Besides, the in situ synthesized Ag nanoparticles (AgNPs) were evenly distributed on the RGO surface. To investigate antibacterial properties Ag-PDA-RGO, different dosages were selected for evaluating the antibacterial activity against Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Escherichia coli. The Ag-PDA-RGO nanocomposites displayed excellent antibacterial property. The antibacterial ratio reached 99.9% against S. aureus and 90.9% against E. coli when the dosage of 100 mg/L Ag-PDA-RGO nanocomposites was 100 μL. The novel Ag-PDA-RGO nanocomposite prepared by a facile yet effective, environmentally friendly, and low-cost method holds great promise in a wide range of modern biomedical applications

Auto-focusing system for microscope based on computational verb controllers

Abstract—In this paper, an auto-focusing system of microscope for integrated circuits (IC) analysis is presented. In this system, the Laplacian algorithm is used as the evaluation function, which provides a reference to the degree of defocus. The auto-focusing controlling algorithm based on computational verb theory consists of two controllers designed: The moving-speed controller and the moving-direction controller. Both controllers work well under the verb-control rules designed in this paper. It has shown that the system can focus accurately and quickly, and it can adjust itself when it is out of focus

Table <b>4.</b> Pairwise <i>F</i>_ST values among the 13 populations surveyed of <i>Apodemus draco</i>.

<p>Populations contain only one sample are exclude in this analyses.</p><p>Numbers in bold indicate statistically significant genetic differentiation (<i>P</i><0.05). Populations are numbered as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0038184#pone-0038184-t001" target="_blank">Table 1</a>.</p

Sampling information of <i>Apodemus draco</i>.

<p>We did not have the coordinates of the individuals in the first five populations because their sequences are from GenBank. Their references and GenBank accession numbers can be found in text.</p

Fifty percent majority rule consensus tree from Bayesian analysis of <i>Apodemus draco</i> based on all the haplotypes of cyt <i>b</i> data.

<p>Numbers represent node supports inferred from Bayesian posterior probability of non-partitioned data and partitioned data, and maximum parsimony bootstrap analyses, respectively. Only values of the main evolutionary clades are shown. The haplotype names can be found in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0038184#pone-0038184-t001" target="_blank">Table 1</a>.</p

The result of McDonald-Kreitman test for cyt <i>b</i> gene of <i>Apodemus draco</i> (N = 126) and <i>A. latronum</i> (N = 68).

<p>Values corrected by Jukes and Cantor (1969) are given in parentheses.</p

Median-joining network of all cyt <i>b</i> haplotypes found in <i>Apodemus draco</i>.

<p>The missing haplotypes in the network are represented by gray dots. Circle sizes are proportional to the number of individuals sharing the same haplotypes. Each mutation step is shown as a short line connecting neighboring haplotypes, and numbers of mutations between haplotypes are indicated near branches if it is greater than one. Haplotype designations can be found in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0038184#pone-0038184-t001" target="_blank">Table 1</a>. Evolutionary clades correspond to the five major clades and three subclades in Fig. 2. Haplotypes from different populations are marked as *.</p