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To obtain a precise 2D/3D image of fissure or karst water, multi-channel magnetic resonance sounding (MRS) systems using edge-to-edge or overlapping receiving coils are needed. Thus, acquiring a nano-volt signal for a small amount of the aquifer and suppressing the mutual coupling between adjacent coils are two important issues for the design of the signal acquisition module in the system. In the present study, we propose to use a passive low pass filter, consisted of a resistance (R) and capacitance (C), to inhibit the mutual coupling effects of the coils. Four low-noise operational amplifiers LT1028, OPA124, AD745, and OP27 were compared with respect to achieving the lowest system noise. As a result, 3 pieces of LT1028 were chosen and connected in parallel to serve as preamplifier, with a sensitivity of 1.4 nV/√Hz at 2 kHz. Experimental results are presented for 2D MRS groundwater investigations conducted in the suburb of Changchun, China. The inversion result is consistent with the result of drilling log, suggesting that the signal acquisition module is well developed.

Forest parks are key protected areas that protect biodiversity and important ecosystems with a high efficiency and low cost and have become an international research area of high interest. Eco-efficiency is an important tool to measure the sustainable development of natural protected areas and provides a valuable decision reference for policy-makers. This research constructs a comprehensive performance evaluation system for forest park ecosystems, economic systems, and environmental systems. The undesired output model (SBM), spatial analysis, and panel Tobit regression model are applied to measure and analyze the forest park eco-efficiency in 30 provinces and autonomous regions of the Chinese mainland from 1990 to 2019, as well as the temporal and spatial differentiation characteristics and their driving factors. The results show that (1) both the average level of eco-efficiency and economic efficiency of forest parks show a declining trend; (2) the eco-efficiency of forest parks shows high-efficiency zones in the northeast and northwest, medium-efficiency zones in the west, and low-efficiency zones in the middle region of the Chinese mainland; (3) forest parks in the eastern region with a higher-than-average efficiency are located in Tianjin and Zhejiang Province, while the western region with lower efficiency is located in Xinjiang, Inner Mongolia, Qinghai, and Gansu Province; and (4) the forest park tourism service quality has an important impact on forest parks’ eco-efficiency, but the entertainment activity has a significant negative impact on the eco-efficiency of forest parks. Finally, suggestions are proposed for the sustainable and green development of forest park ecological tourism.

Background: Although we previously revealed that DNA-dependent protein kinase catalytic subunit (DNA-PKcs) is overexpressed in pancreatic ductal adenocarcinoma (PDAC) and important for gemcitabine resistance, the role of DNA-PKcs in the progression and metastasis of PDAC remain unclear. To date, the upstream signaling events stimulating DNA-PKcs overexpression in PDAC are still not well characterized. Methods: Expression of DNA-PKcs was measured by western blot. The levels of miRNA-101 and lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) were detected by real-time PCR. Cell viability was determined by CCK-8. Cell migration and cell invasion were measured by transwell assay. The regulatory relationship between NEAT1 and miR-101 was determined by a luciferase assay. Results: DNA-PKcs expression was significantly elevated in human PDAC tissues and cells. DNA-PKcs overexpression was correlated with TNM stage and lymph node metastasis. Higher expression of DNA-PKcs was closely correlated with patients of worse overall survival (OS). DNA-PKcs knockdown suppresses malignant behaviors of PDAC cells. Further study showed that miRNA-101 level was decreased in PDAC tissues and cells, which could be responsible for DNA-PKcs overexpression and DNA-PKcs mediated oncogenic actions in PDAC cells. Moreover, NEAT1 functions as an oncogene influencing cell proliferation, migration and invasion in part by serving as a competing endogenous RNA (ceRNAs) modulating miR-101 expression, leading to up-regulation of DNA-PKcs. Conclusion: These findings suggest that NEAT1/miR-101-dependent up-regulation of DNA-PKcs promotes the malignant behaviors of PDAC cells. The NEAT1/miR-101/DNA-PKcs axis may serve as a viable prognostic marker and therapeutic target for PDAC.