The detection of methane has always been an important part of coal mine safety. In order to improve the methane measurement accuracy in coal mines and to determine the influence of environmental ...interference factors on the measurement results, we designed a spherical, experimental chamber simulating the on-site environment of an underground coal mine containing methane, in which various environmental interference factors can be superimposed. The simulation chamber can generate a uniform and controllable dust environment, a controllable methane environment with concentrations below that which would trigger an alarm, controllable humidity, and environments characterized by other interference factors. Based on computational simulations of the experimental chamber with varying dust-particle-concentration distributions using a single particle size, an optimal design for the chamber has been realized in terms of the rapid mixing of dust and the flow field. Finally, we constructed an underground methane concentration measurement system for coal mines and assessed the influences of different dust concentrations and relative humidity values on the performance of methane measurements, providing a means for improving the measurement accuracy of underground coal mine, spectral, absorption-type methane sensors.
Prim‐pol is a recently identified DNA primase‐polymerase belonging to the archaeao‐eukaryotic primase (AEP) superfamily. Here, we characterize a previously unrecognized prim‐pol in human cells, which ...we designate hPrimpol1 (human primase‐polymerase 1). hPrimpol1 possesses primase and DNA polymerase activities in vitro, interacts directly with RPA1 and is recruited to sites of DNA damage and stalled replication forks in an RPA1‐dependent manner. Cells depleted of hPrimpol1 display increased spontaneous DNA damage and defects in the restart of stalled replication forks. Both RPA1 binding and the primase activity of hPrimpol1 are required for its cellular function during DNA replication. Our results indicate that hPrimpol1 is a novel factor involved in the response to DNA replication stress.
This study identifies the first human DNA primase‐polymerase, which is required for stalled replication fork restart and the maintenance of genome integrity.
Magnetically retrievable bismuth tungstate/iron oxide/sodium montmorillonite composite (Bi
2
WO
6
/Fe
3
O
4
/Na-MMT) was synthesized via a simple solvothermal process. The structure and morphology of ...as-synthesized composite have been investigated by a series of characterization techniques, the photocatalytic performance was evaluated through the degradation of rhodamine B (RhB) under visible light irradiation, and the possible photodegradation mechanism also has been proposed based on the active species trapping experiments. The results indicated that the Fe
3
O
4
/Na-MMT as a magnetic carrier shows excellent adsorption capacity and electron transfer performance, and the h
+
radicals could be the main active species in the photocatalytic degradation of RhB. Furthermore, the composite exhibited an extraordinary enhanced photocatalytic activity, much more higher than those of the pure Bi
2
WO
6
and montmorillonite samples, and the composite possesses great paramagnetic properties that contribute a magnetically retrievable performance for solid–liquid separation.
Brassica napus, a hybrid resulting from the crossing of Brassica rapa and Brassica oleracea, is one of the most important oil crops. Despite its significance, B. napus productivity faces substantial ...challenges due to heavy metal stress, especially in response to cadmium (Cd), which poses a significant threat among heavy metals. Natural resistance-associated macrophage proteins (NRAMPs) play pivotal roles in Cd uptake and transport within plants. However, our understanding of the role of BnNRAMPs in B. napus is limited. Thus, this study aimed to conduct genome-wide identification and bioinformatics analysis of three Brassica species: B. napus, B. rapa, and B. oleracea.
A total of 37 NRAMPs were identified across the three Brassica species and classified into two distinct subfamilies based on evolutionary relationships. Conservative motif analysis revealed that motif 6 and motif 8 might significantly contribute to the differentiation between subfamily I and subfamily II within Brassica species. Evolutionary analyses and chromosome mapping revealed a reduction in the NRAMP gene family during B. napus evolutionary history, resulting in the loss of an orthologous gene derived from BoNRAMP3.2. Cis-acting element analysis suggested potential regulation of the NRAMP gene family by specific plant hormones, such as abscisic acid (ABA) and methyl jasmonate (MeJA). However, gene expression pattern analyses under hormonal or stress treatments indicated limited responsiveness of the NRAMP gene family to these treatments, warranting further experimental validation. Under Cd stress in B. napus, expression pattern analysis of the NRAMP gene family revealed a decrease in the expression levels of most BnNRAMP genes with increasing Cd concentrations. Notably, BnNRAMP5.1/5.2 exhibited a unique response pattern, being stimulated at low Cd concentrations and inhibited at high Cd concentrations, suggesting potential response mechanisms distinct from those of other NRAMP genes.
In summary, this study indicates complex molecular dynamics within the NRAMP gene family under Cd stress, suggesting potential applications in enhancing plant resilience, particularly against Cd. The findings also offer valuable insights for further understanding the functionality and regulatory mechanisms of the NRAMP gene family.
Seepage in the underground rock and soil is one of the main causes of geological disasters. Precursor information for geological disasters is provided by accurately measuring the seepage flow in rock ...and soil, so as to provide disaster warnings in time. This article analyzes the principle of seepage measurement in rock and soil based on heat transfer, deduces the relationship between the flow rate and temperature of the fluid with a seepage sensor, designs and manufactures an entire seepage measurement sensor, and designs a seepage measurement circuit. Finally, a set of portable geotechnical seepage measuring instruments is designed. An experimental platform is designed to realize seepage flow and temperature change experiments with the seepage sensor, it is proved that the sensor can effectively measure the seepage flow for different experimental samples, the measurement range is 0.06–0.160 ml/s. Based on the measured characteristic temperature of the seepage sensor, the calculated seepage flow is obtained, the relative error between the calculated value and the measured value is within 3%.
Mcm2-7 helicase is loaded onto double-stranded origin DNA as an inactive double hexamer (DH) in G1 phase. The mechanisms of Mcm2-7 remodeling that trigger helicase activation in S phase remain ...unknown. Here, we develop an approach to detect and purify the endogenous DHs directly. Through cellular fractionation, we provide in vivo evidence that DHs are assembled on chromatin in G1 phase and separated during S phase. Interestingly, Mcm10, a robust MCM interactor, co-purifies exclusively with the DHs in the context of chromatin. Deletion of the main interaction domain, Mcm10 C terminus, causes growth and S phase defects, which can be suppressed through Mcm10-MCM fusions. By monitoring the dynamics of MCM DHs, we show a significant delay in DH dissolution during S phase in the Mcm10-MCM interaction-deficient mutants. Therefore, we propose an essential role for Mcm10 in Mcm2-7 remodeling through formation of a cell-cycle-regulated supercomplex with DHs.
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•MCM undergoes cell-cycle-dependent change between double and single hexameric forms•Mcm10 directly associates with the double hexameric MCM on chromatin•Mcm10 C terminus-mediated MCM interaction is crucial in double hexamer splitting
In eukaryotes, DNA helicase MCM is loaded as an inactive dimeric ring in G1 phase. By using an in vivo biochemical approach, Quan et al. show that Mcm10 plays a critical role in its dissolution into two functional single rings to initiate bidirectional chromosome replication.
Oligomeric Proanthocyanidins (OPCs), as a class of compounds widely found in plants, are particularly abundant in grapes and blueberries. It is a polymer comprising many different monomers, such as ...catechins and epicatechins. The monomers are usually linked to each other by two types of links, A-linkages (C-O-C) and B-linkages (C-C), to form the polymers. Numerous studies have shown that compared to high polymeric procyanidins, OPCs exhibit antioxidant properties due to the presence of multiple hydroxyl groups. This review describes the molecular structure and natural source of OPCs, their general synthesis pathway in plants, their antioxidant capacity, and potential applications, especially the anti-inflammatory, anti-aging, cardiovascular disease prevention, and antineoplastic functions. Currently, OPCs have attracted much attention, being non-toxic and natural antioxidants of plant origin that scavenge free radicals from the human body. This review would provide some references for further research on the biological functions of OPCs and their application in various fields.
With the continuous progress of artificial intelligence and other manufacturing technologies, there is promising potential for wearable piezoresistive sensors in human physiological signal detection ...and bionic robots. Here, we present a facile solution-mixing process to fabricate a multiwalled carbon nanotube/graphite powder (MWCNT@Gp) film, which has high sensitivity and great linearity and is more oriented to flexible piezoresistive sensors. The sensor consists of two parts: a spinosum microstructure shaped by a sandpaper template and polydimethylsiloxane (PDMS) as the top substrate and interdigital electrodes as the bottom substrate. The experiments we have conducted show that these two parts provide good protection to the MWCNTs@Gp film and improve sensor sensitivity. Additionally, the sensitivity of the optimal ratio of multiwalled carbon nanotubes and graphite powder is analyzed. The 5%MWCNT@5%Gp composites were found to have relatively good conductivity, which is convenient for the fabrication of conductive films of piezoresistive sensors. Finally, we conducted application experiments and found that the flexible piezoresistive sensor can detect minute signals of human motion and different pressure points. This indicates the feasibility of portable sensors in electronic skin and smart devices.
Lysine methylation and methyltransferases are widespread in the third domain of life, archaea. Nevertheless, the effects of methylation on archaeal proteins wait to be defined. Here, we report that ...recombinant sisMCM, an archaeal homolog of Mcm2-7 eukaryotic replicative helicase, is methylated by aKMT4 in vitro. Mono-methylation of these lysine residues occurs coincidently in the endogenous sisMCM protein purified from the hyperthermophilic Sulfolobus islandicus cells as indicated by mass spectra. The helicase activity of mini-chromosome maintenance (MCM) is stimulated by methylation, particularly at temperatures over 70°C. The methylated MCM shows optimal DNA unwinding activity after heat-treatment between 76 and 82°C, which correlates well with the typical growth temperatures of hyperthermophilic Sulfolobus. After methylation, the half life of MCM helicase is dramatically extended at 80°C. The methylated sites are located on the accessible protein surface, which might modulate the intra- and inter- molecular interactions through changing the hydrophobicity and surface charge. Furthermore, the methylation-mimic mutants of MCM show heat resistance helicase activity comparable to the methylated MCM. These data provide the biochemical evidence that posttranslational modifications such as methylation may enhance kinetic stability of proteins under the elevated growth temperatures of hyperthermophilic archaea.
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