An Optimized Thermal Feedback Methodology for Accurate Temperature Control and High Amplification Efficiency during Fluorescent qPCR

Traditional qPCR instrument is combined with CMOS and a personal computer, and a photoelectric feedback automatic fluorescence detection system is designed to realize quantitative real-time PCR. The key to reaction efficiency lies in how to ensure that the temperature of the detection reagent completely matches the set temperature. However, for most traditional real-time fluorescent PCR systems, the temperature cycling is controlled by detecting the temperature of the heating well plate. It cannot directly measure the temperature in the reaction reagent PCR tube, which will cause the deviation in the actual temperature of the reagent to be as expected. Therefore, in this paper, we raise a method of directly detecting the temperature in the reaction tube of the reagent during the temperature cycling is adopted. According to the deviation from the expected value, the set temperature of the PCR instrument is adjusted to make the actual temperature of the reagent closer to the expected value. Through this method, we also realized the temperature calibration and optimization of the TEC circulation system we built. Experiments show that this low-cost, portable real-time quantitative PCR system can detect and analyze pathogens in situ

Toward carbon neutrality: Uncovering constraints on critical minerals in the Chinese power system

China has set up its ambitious carbon neutrality target, which mainly relies on significant energy-related carbon emissions reduction. As the largest important contributing sector, power sector must achieve energy transition, in which critical minerals will play an essential role. However, the potential supply and demand for these minerals are uncertain. This study aims to predict the cumulative demand for critical minerals in the power sector under different scenarios via dynamic material flow analysis (DMFA), including total demands, supplies and production capacities of different minerals. Then, these critical minerals are categorized into superior and scarce resources for further analysis so that more detailed results can be obtained. Results present that the total minerals supply will not meet the total minerals demand (74260 kt) in 2060. Serious resource shortages will occur for several key minerals, such as Cr, Cu, Mn, Ag, Te, Ga, and Co. In addition, the demand for renewable energy will be nearly fifty times higher than that of fossil fuels energy, implying more diversified demands for various minerals. Finally, several policy recommendations are proposed to help improve the overall resource efficiency, such as strategic reserves, material substitutions, and circular economy

Additional file 1 of Toward efficient and high-fidelity metagenomic data from sub-nanogram DNA: evaluation of library preparation and decontamination methods

Additional file 1: Table S1. Composition and sequences of the synthetic DNA material sequins. Table S2. Characteristics of library construction kits. Table S3. 495 core microbial contaminations at the genus level

Additional file 2 of Toward efficient and high-fidelity metagenomic data from sub-nanogram DNA: evaluation of library preparation and decontamination methods

Additional file 2: Fig. S1. Sequencing depth and rarefaction curves. Fig. S2. Performance of WGA in metagenomics using sub-nanogram DNA. Fig. S3. Comparison of non-WGA-based DNA library preparation methods. Fig. S4. Characteristics of contaminating DNA. Fig. S5. Thresholds and performance of in silico decontamination methods