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Objective To develop an MATLAB algorithm for the automated measurement of motor neuron (MN) neurites and apply this algorithm to evaluate the organophosphate flame retardant tris (2-chloroethyl) phosphate (TCEP) on the growth of MN neurites. Methods Human embryonic stem cells were induced to gradually differentiate into MN. After the neurites were labelled with βⅢ-tubulin for fluorescence image processing, an image process algorithm was developed to automatically analyze the neurite and changes in neurite network area after pollutant treatment. During MN differentiation, the cells were treated with different concentrations of TCEP (0, 25, 50 and 100 μmol/L). Results MNs were successfully induced with the expression of choline acetyltransferase. The developed image recognition algorithm could analyze images in batches, and calculate the pixel area occupied by neural network, and reserve weak neurites by optimizing neurite retention threshold to improve the accuracy of measurement. The quantification data from image process algorithm showed that TCEP significantly decreased the percentage of neurite network area since the dose started from 50 μmol/L (P < 0.05). Conclusion An image process algorithm is successfully developed for automated measurement of neurites based on the human MN neurite model. Moreover, this algorithm can be applied to the toxicity assessment of TCEP.

Enhanced geothermal system (EGS) technologies have been developed to improve geothermal energy production from hot dry rock (HDR). In this study, discrete fracture network models for geometric topological networks that consider different parameters (the fracture density and the fracture length index) were built on the basis of fractal geometry theory. The heat extraction processes of CO2 and water as the working fluid through different discrete fracture networks were simulated with the application of the thermal–hydraulic–mechanical (THM) coupled method. A series of sensitivity analyses were carried out to reveal the influences of fracture parameters on heat transfer processes. Based on the simulation results, heat extraction efficiencies and temperature distributions in the reservoir of CO2 and water as the working fluid were compared, which showed that CO2 as the working fluid can bring a faster thermal breakthrough. It was found that the fracture length index a = 2.5 and the fracture density I = 5.0 can provide the highest heat extraction rate compared with other cases. This study provides a detailed analysis of fracture parameters and working fluids, which will contribute to the optimized management of geothermal energy production. [ABSTRACT FROM AUTHOR]

Valproic acid (VPA), a clinically approved small molecule, has been reported to activate Wnt signalling that is critical for dorsal–ventral (DV) patterning of neural tube. However, little is known about the impact of VPA on DV patterning process. Here, we show that even though VPA has a negative impact on the early formation of human neural tube organoids (hNTOs), it significantly enhances the efficiency of ventrally patterned hNTOs, when VPA is added during the entire differentiation process. RNA sequencing and RT‐qPCR analysis demonstrates VPA activates endogenous Wnt signalling in hNTOs. Surprisingly, transcriptome analysis also identifies upregulation of genes for degradation of GLI2 and GLI3 proteins, whose truncated fragment are transcriptional repressors of Shh signalling. The Western‐blot analysis confirms the increase of GLI3R proteins after VPA treatment. Thus, VPA might enhance ventral patterning of hNTOs through both activating Wnt, which can antagonise Shh signalling by inducing GLI3 expression, and/or inhibiting Shh signalling by inducing GLI protein degradation. We further obtain results to show that VPA still increases patterning efficiency of hNTOs with a weak influence on their early formation when the initiation time of VPA is delayed and its duration is reduced. Taken together, this study demonstrates that VPA enhances the generation of more reproducible hNTOs with ventral patterning, opening the avenues for the applications of hNTOs in developmental biology and regenerative medicine. [ABSTRACT FROM AUTHOR]

This study proposed an efficient way of direct sewage pre-concentration by a combined coagulation microfiltration (CCM) system and an optimal operational strategy of aeration. Compared to two typical technologies for sewage pre-concentration, i.e. direct sewage microfiltration (DSM) and continuous aerated sewage microfiltration (ASM), the CCM system under optimal aeration strategy showed higher concentration efficiency and slower permeability decline (i.e. better control of membrane fouling), and easier collection of retained organic matter (OM). A lab-scale CCM reactor was running continuously for 295 h, and a concentrate of about 16,000 mg COD/L was produced at an average net flux of 13.3 L/(m 2 h) and an influent OM recovery of nearly 70%, which was higher than the concentrate produced by a high-loaded membrane bioreactor (MBR) with one day solids retention time. The use of chemical coagulant was found to have little impact on the following anaerobic digestion (AD) process, for anaerobic biodegradability of the concentrate is 56.5% (close to the typical value for blackwater). The integration of the CCM and AD processes could achieve a net energy production of 0.0098 kW h/m 3 after deduction of 0.0919 kW h/m 3 required for the operation of the CCM system, thus showing promise as an effective OM concentration method for energy recovery from sewage. [ABSTRACT FROM AUTHOR]