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Electroencephalography can assess connectivity between brain hemispheres, potentially influencing cognitive functions. Much of the existing electroencephalography research primarily focuses on undirected connectivity, leaving uncertainties about directed connectivity alterations between left-right brain hemispheres or frontal-posterior lobes in mild cognitive impairment. We analyzed resting-state electroencephalography data from 34 mild cognitive impairment individuals and 23 normal controls using directed transfer function and graph theory for directed network analysis. Concerning the dominance within left-right hemispheres or frontal-posterior lobes, the mild cognitive impairment group exhibited decreased connectivity within the frontal compared with posterior brain regions in the delta and theta bands. Regarding the dominance between the brain hemispheres or lobes, the mild cognitive impairment group showed reduced connectivity from the posterior to the frontal regions versus the reverse direction in the same bands. Among all participants, the intra-lobe frontal-posterior dominance correlated positively with executive function in the delta and alpha bands. Inter-lobe dominance between frontal and posterior regions also positively correlated with executive function, attention, and language in the delta band. Additionally, interhemispheric dominance between the left and right hemispheres positively correlated with attention in delta and theta bands. These findings suggest altered cerebral dominance in mild cognitive impairment, potentially serving as electrophysiological markers for neurocognitive disorders., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The evolution of body size within and among species is predicted to be influenced by multifarious environmental factors. However, the specific drivers of body size variation have remained difficult to understand because of the wide range of proximate factors that covary with ectotherm body sizes across populations with varying local environmental conditions. Here, we used female Eremias argus lizards collected from different populations across their wide range in China, and constructed linear mixed models to assess how climatic conditions and/or available resources at different altitudes shape the geographical patterns of lizard body size across altitude. Lizard populations showed significant differences in body size across altitudes. Furthermore, we found that climatic and seasonal changes along the altitudinal gradient also explained variations in body size among populations. Specifically, body size decreased with colder and drier environmental conditions at high altitudes, reversing Bergmann's rule. Limited resources at high altitudes, measured by the low vegetative index, may also constrain body size. Therefore, our study demonstrates that multifarious environmental factors could strongly influence the intraspecific variation in organisms' body size., Competing Interests: The authors declare no competing interest., (© 2023 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

The complete mitochondrial genome of the Leptobrachella alpina Fei, Ye, and Li 1990, was assembled for the first time. The mitogenome of this species was 17,763 bp in length, containing 13 protein-coding genes, two ribosomal RNA genes (12S rRNA and 16S rRNA), 22 transfer RNA genes (tRNA), and a non-coding control region (D-loop). The base content of the mitogenome was that A, T, G, and C occupied 28.5%, 30.8%, 15.1%, and 25.6%, respectively. The phylogenetic analysis was conducted based on 17 complete mitogenome sequences of the family Megophryidae by the Bayesian inference approach. The phylogenetic tree suggested that Leptobrachium and Oreolalax clustered into a clade and formed a sister group with Leptobrachella. This work is critical for the further genetic research and conservation of this species., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

The complete mitochondrial genome of the Oreolalax lichuanensis was determined. It is a circular molecule of 17 702 bp in size and consists of 13 protein-coding genes, 23 tRNA genes, two rRNA genes and a control region (D-loop). The base composition on light strand was 28.0% A, 32.2% T, 24.9% C and 14.9% G. Compared with most other vertebrates, this mitogenome appear a tandem duplication of tRNA - Met gene. This study will facilitate the further research of the population genetics of this species and systematic study of the genus Oreolalax ., Competing Interests: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper., (© 2016 The Author(s). Published by Taylor & Francis.)

We determined the complete mitochondrial genome of Kaloula rugifera in this work. The mitogenome was 17,073 bp in length, containing 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region (D-loop). The base composition of the light strand was 29.7% A, 30.4% T, 25.7% C and 14.2% G. The gene order and contents of it is identical to most amphibian mitogenome. All protein-coding genes began with ATG as start codon except ND1 gene beginning with GTG and COI gene beginning with ATA. Five protein-coding genes (COII, ATP 6, COIII, ND3 and ND4) ended with incomplete stop codon T. The 22 tRNA genes with the size ranging from 65 bp to 73 bp were interspersed along the whole genome. The D-loop region containing tandem repetition was 1675 bp in length and heavily biased to A + T nucleotides.

Ion mobility spectrometry (IMS) was explored in the selective detection of nitrobenzene compounds in industrial waste water and surface water, and the selectivity was theoretically elucidated with the transformation energy in the product ion formation reaction. A linear detection range of 0.5-50 ppm and a limit of detection (LOD) of 0.1 ppm were found for 2,4,6-trinitrotoluene (TNT). With the IMS as the detection system of molecularly imprinted polymer (MIP) separation technique, the MIP-IMS system was proved to be excellent method to detect trace amount of nitrobenzene compounds in surface water, in which more than 87% of nitrobenzene compounds could be adsorbed on MIPs with 90-105% of recovery., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The method of detecting trace 1,4-dioxane in water using membrane extraction coupled with gas chromatography/differential mobility spectrometry (GC/DMS) was developed. The parameters including radio frequency voltage, sampling flow rate, permeation time and trapping time were optimized to 1000 V, 50 mL/min, 30 min and 150 s, respectively. The linear range for dioxane was obtained from 2.0 μg/L to 20.0 μg/L. The LOD was found to be 0. 67 μg/L. The specificity towards 1,4-dioxane in the presence of five chlorinated hydrocarbons was improved by using two-dimensional GC separation with optimized DMS compensation voltage. This method paves a way for developing field-deployable sensors for real-time monitoring contaminants in groundwater.

This paper introduces a simple method for selective and sensitive detection of black powder by adding chlorinated hydrocarbons in the drift gas instead of changing the structure of conventional ion mobility spectrometer (IMS). The function of chloride modifiers was to substitute Cl(-)(H₂O)n for [O₂⁻ (H₂O)(n)] in the drift region so as to avoid the overlap between O₂⁻ (H₂O)(n) and sulfur ion peaks. Among CH₂Cl₂, CHCl₃ and CCl₄, CCl₄ was chosen as the modifier due to the best peak-to-peak resolution and stability towards the fluctuation of modifier concentration. With 1.4 ppm CCl₄ as the modifier, the minimum detectable quantity of 0.1 ng for sulfur was achieved. Moreover, this method showed the ability for detection of common explosives at sub-nanogram level, such as black powder (BP), ammonium nitrate fuel oil (ANFO), 2,4,6-trinitrotoluene (TNT), and pentaerythritol tetranitrate (PETN). In summary, this method requiring no configuration modification has high sensitivity and selectivity, and consumes trace amount of modifier. And these characteristics make it easy to be adopted in current deployed IMS to detect black powder explosives., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The complete mitochondrial genome of a stream-dwelling frog species Paramegophrys oshanensis was determined. This mitogenome was 17,747 bp in length, containing 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and a control region (D-loop). The base composition of the light strand was 28.77% A, 29.85% T, 26.26% C, and 15.11% G. Compared with most other vertebrates, this mitogenome has some different features: a non-tandem duplication of tRNA-Met gene (forming tRNA-Met1 and tRNA-Met2 genes), the replacement of tRNA-Trp gene by a 72-bp noncoding region translocated from the cluster of WANCY to the back of Cytb gene, the translocation of tRNA-Val gene from the front of 16S rRNA to the back of tRNA-Met1 gene, and the translocation of tRNA-Pro gene from the front of D-loop region to the front of tRNA-Met2 gene. Three kinds of tandem repeats with size ranging from 71 to 92 bp were detected within D-loop region.

A nano-electrospray ionization-ion mobility spectrometer (nanoESI-IMS) was built up. Firstly, the effects of the parameters such as drift gas flow rate and solvent flow rate on the desolvation capability were studied and optimized. Then, a series of compounds were used to characterize the nanoESI-IMS system. The results showed that, complete desolvation was achieved for nano-electrospray ion droplets with the nanoESI-IMS apparatus. The limit of detection of this instrument for trioctylamine could reach 10 microg/L. Finally, this instrument was coupled to the high performance liquid chromatography (HPLC) as a detector for amines analysis. A test mixture containing triethylamine, diethylamine and butylamine was successfully separated and determined by the HPLC-nanoESI-IMS system. Linear response ranges of about two orders of magnitude were achieved for triethylamine, diethylamine and butylamine with this system.