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The spatial patterns of field arthropod communities are an essential part of ecology and can provide fundamental data regarding field ecological processes and reveal the mechanism of ecosystem biodiversity maintenance. This study investigated the spatial distribution pattern of field insect communities to detect the spatial relationships between insect communities in farmland. The study site was located at the Dehui Agro-ecological Experimental Station of Black Soil, Jilin, China. Insect communities and environmental factors were sampled at 121 uniformly distributed points in a 400 × 400 m plot in August, September, and October 2015. The analysis revealed that insect communities from June to October demonstrated significant spatial correlation, and 6085 samples of 47 species and 47 families in 11 orders were collected from the insect community in the farmland. The farmland insect community structure changes and dynamic changes of nutritional function groups occur with time. According to the 400 x 400 m plot, the diversity of farmland insect communities and functional groups is maintained at a relatively high and stable level. In this study, a total of 6085 samples of corn farmland insects were obtained using the fluke method and direct observation method, including 11 orders, 26 families and 47 species, 4 absolute dominant populations, 6 main dominant populations, and 37 other populations. These studies can provide help for pest control in the spring corn area of Northeast China. [ABSTRACT FROM AUTHOR]

Spatial distribution is an important topic in community ecology and a key to understanding the structure and dynamics of populations and communities. However, the available information related to the spatial patterns of soil mite communities in long-term tillage agroecosystems remains insufficient. In this study, we examined the spatial patterns of soil mite communities to explain the spatial relationships between soil mite communities and soil parameters. Soil fauna were sampled three times (August, September and October 2015) at 121 locations arranged regularly within a 400 m × 400 m monitoring plot. Additionally, we estimated the physical and chemical parameters of the same sampling locations. The distribution patterns of the soil mite community and the edaphic parameters were analyzed using a range of geostatistical tools. Moran’s I coefficient showed that, during each sampling period, the total abundance of the soil mite communities and the abundance of the dominant mite populations were spatially autocorrelated. The soil mite communities demonstrated clear patchy distribution patterns within the study plot. These patterns were sampling period-specific. Cross-semivariograms showed both negative and positive cross-correlations between soil mite communities and environmental factors. Mantel tests showed a significant and positive relationship between soil mite community and soil organic matter and soil pH only in August. This study demonstrated that in the cornfield, the soil mite distribution exhibited strong or moderate spatial dependence, and the mites formed patches with sizes less than one hundred meters. In addition, in this long-term tillage agroecosystem, soil factors had less influence on the observed pattern of soil mite communities. Further experiments that take into account human activity and spatial factors should be performed to study the factors that drive the spatial distribution of soil microarthropods. [ABSTRACT FROM AUTHOR]

Treatments for triple-negative breast cancer (TNBC) are limited; intermediate-conductance calcium-activated potassium (SK4) channels are closely involved in tumor progression, but little is known about these channels in TNBC. We aimed to investigate whether SK4 channels affect TNBC. First, by immunohistochemistry (IHC) and western blotting (WB), increased SK4 protein expression in breast tumor tissues was detected relative to that in non-tumor breast tissues, but there was no apparent expression difference between various subtypes of breast cancer (p>0.05). Next, functional SK4 channels were detected in the TNBC cell line MDA-MB-231 using WB, real-time PCR, immunofluorescence and patch-clamp recording. By employing SK4 specific siRNAs and blockers, including TRAM-34 and clotrimazole, in combination with an MTT assay, a colony-formation assay, flow cytometry and a cell motility assay, we found that the suppression of SK4 channels significantly inhibited cell proliferation and migration and promoted apoptosis in MDA-MB-231 cells (p<0.05). Further investigation revealed that treatment with epidermal growth factor (EGF)/basic fibroblast growth factor (bFGF) caused MDA-MB-231 cells to undergo the epithelial-mesenchymal transition (EMT) and to show increased SK4 mRNA expression. In addition, the down-regulation of SK4 expression inhibited the EMT markers Vimentin and Snail1. Collectively, our findings suggest that SK4 channels are expressed in TNBC and are involved in the proliferation, apoptosis, migration and EMT processes of TNBC cells. [ABSTRACT FROM AUTHOR]