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Abstract Biochar, a soil conditioner containing significant amounts of polycyclic aromatic hydrocarbons (PAHs), has gained widespread popularity in agricultural practices due to its advantages in improving soil fertility and carbon sequestration. While biochar may increase soil black carbon (BC) and PAH contents, the quantitative accumulation of BC and PAHs in different soil environments under varying biochar addition dosages remains poorly understood. Here, we investigated the content and composition of black carbon (evaluated using benzene polycarboxylic acids, BPCAs) and PAHs in soils treated with different biochar addition dosages from two long-term experimental farmlands in Ningxia (5-year) and Shandong (7- and 11-year), China. Results showed that increasing cumulative biochar dosage caused elevated contents of black carbon and PAHs, accompanied by decreases in their retention efficiencies. Contrasting retention was observed between sites, with the Shandong site characterized by higher retention efficiencies of BPCAs and lower retention efficiencies of PAHs, possibly owing to its higher temperature, more sandy soil texture, less irrigation, and lower sunlight intensity. Despite both black carbon and PAHs originating from biochar and sharing similar condensed aromatic structures, there was no significant correlation between the contents of black carbon and PAHs, indicating distinct behaviors and fates of these compounds. These findings emphasize the importance of optimizing biochar addition dosages and considering site-specific environmental factors for effective soil black carbon sequestration through biochar application. Graphical Abstract

High-throughput identification and cultivation of functional-yet-uncultivable microorganisms is a fundamental goal in environmental microbiology. It remains as a critical challenge due to the lack of routine and effective approaches. Here, we firstly proposed an approach of stable-isotope-probing and metagenomic-binning directed cultivation (SIP-MDC) to isolate and characterize the active phenanthrene degraders from petroleum-contaminated soils. From SIP and metagenome, we assembled 13 high-quality metagenomic bins from 13C-DNA, and successfully obtained the genome of an active PHE degrader Achromobacter (genome-MB) from 13C-DNA metagenomes, which was confirmed by gyrB gene comparison and average nucleotide/amino identity (ANI/AAI), as well as the quantification of PAH dioxygenase and antibiotic resistance genes. Thereinto, we modified the traditional cultivation medium with antibiotics and specific growth factors (e.g., vitamins and metals), and separated an active phenanthrene degrader Achromobacter sp. LJB-25 via directed isolation. Strain LJB-25 could degrade phenanthrene and its identity was confirmed by ANI/AAI values between its genome and genome-MB (>99 %). Our results hinted at the feasibility of SIP-MDC to identify, isolate and cultivate functional-yet-uncultivable microorganisms (active phenanthrene degraders) from their natural habitats. Our findings developed a state-of-the-art SIP-MDC approach, expanded our knowledge on phenanthrene biodegradation mechanisms, and proposed a strategy to mine functional-yet-uncultivable microorganisms.

This paper empirically investigates the impact of industrial robot use on China’s labor market using data from 13 segments of manufacturing industry between 2006 and 2016. According to the findings, the use of industrial robots has a displacement effect on labor demand in manufacturing industry. The specific performance is that for every 1% increase in industrial robot stock, labor demand falls by 1.8%. After endogenous processing and a robustness test, this conclusion remains valid. This paper also discusses the effects of industrial robots across industries and genders. According to the results, industrial robot applications have a more pronounced displacement effect in low-skilled manufacturing than in high-skilled manufacturing. In comparison to female workers, industrial robot applications are more likely to decrease the demand for male workers. Moreover, this paper indicates that the displacement effect is significantly influenced by labor costs. Finally, we make appropriate policy recommendations for the labor market’s employment stability based on the findings.

Rhizoremediation is a promising remediation technology for the removal of soil persistent organic pollutants (POPs), especially benzo[a]pyrene (BaP). However, our understanding of the associations among rhizospheric soil metabolites, functional microorganisms, and POPs degradation in different plant growth stages is limited. We combined stable-isotope probing (SIP), high-throughput sequencing, and metabolomics to analyze changes in rhizospheric soil metabolites, functional microbes, and BaP biodegradation in the early growth stages (tillering, jointing) and later stage (booting) of ryegrass. Microbial community structures differed significantly among growth stages. Metabolisms such as benzenoids and carboxylic acids tended to be enriched in the early growth stage, while lipids and organic heterocyclic compounds dominated in the later stage. From SIP, eight BaP-degrading microbes were identified, and most of which such as Ilumatobacter and Singulisphaera were first linked with BaP biodegradation. Notably, the relationship between the differential metabolites and BaP degradation efficiency further suggested that BaP-degrading microbes might metabolize BaP directly to produce benzenoid metabolites (3-hydroxybenzo[a]pyrene), or utilize benzenoids (phyllodulcin) to stimulate the co-metabolism of BaP in early growth stage; some lipids and organic acids, e.g. 1-aminocyclopropane-1-carboxylic acid, might provide nutrients for the degraders to promote BaP metabolism in later stage. Accordingly, we determined that certain rhizospheric metabolites might regulate the rhizospheric microbial communities at different growth stages, and shift the composition and diversity of BaP-degrading bacteria, thereby enhancing in situ BaP degradation. Our study sheds light on POPs rhizoremediation mechanisms in petroleum-contaminated soils.

Di-(2-ethylhexyl) phthalate (DEHP) is a dominant phthalic acid ester in the environment and commonly occurs at high concentration in agricultural soils. Its influence on the soil microbial community has been widely reported, while research related to its effects on microbial structure, function, and interactions in the rhizosphere, a microbial hotspot region in the terrestrial ecosystem, is still limited. This study investigated the response of microbes in the rhizosphere to DEHP contamination. DEHP reduced microbial quantity, shifted the microbial community structure, and enriched the soil bacteria with potential DEHP degraders. Although the rhizosphere can alleviate DEHP toxicity, DEHP still played an important role in microbial community construction in the rhizosphere. Interestingly, some microbes were influenced by the synergistic toxicity effect of DEHP addition and plant growth, and there were significant differences in their relative abundance and alpha diversity in soil treated with both DEHP and planting compared to soils with just DEHP spiking or planting. The genes related to cell motility, metabolism of terpenoids and polyketides, protein families, genetic information processing, and replication and repair pathways changed only in soil treated with both DEHP and planting further proved the existence of synergistic toxicity. Anyway, the impact of DEHP on microbial function in the rhizosphere was important with 52.42‰ of the genes being changed. The change in cell motility, biofilm formation, and genes related to the quorum sensing pathway might affect the relationship between microbes, which play a crucial role in ecosystem function. This was further proven by changes in the microbial co-occurrence pattern. Our results can benefit risk evaluation of DEHP to microbial community in the rhizosphere, which is important for the effective function of terrestrial ecosystems and soil health.

Mass Rapid Transit (MRT) systems, i.e. subway systems, all over the world, are experiencing an increase in ridership. This also means that in case of an unplanned MRT service disruption, the number of affected passengers is larger, requiring a fast and comprehensive response. In this paper, we thus study the disruption management of MRT systems. We develop an optimization model to identify the optimal bridging plan in response to an MRT disruption, so that the negative effects of a disruption could be minimized. Our approach supports deployment of multiple types of bridging buses, reflecting the diversity of vehicle types in a typical public transportation provider’s vehicle fleet. The optimization objective of our approach is to decrease the travel delay of passengers and increase the number of passengers who can be served. We demonstrate the effectiveness of our approach on a hypothetical case study in the central business district of Singapore. Moreover, we validate our analytical results with microscopic simulation, showing that our simplified analytical optimization approach can be used for disruption response planning. Some deviations indicate, however, that a combined simulation and optimization approach yields better results to obtain an effective bridging plan.

Per- and polyfluoroalkyl substances (PFASs) are ubiquitous in the environment but pose potential risks to ecosystems and human health. The soil–plant system plays an important role in the bioaccumulation of PFASs. Because most PFASs in the natural environment are anionic and amphiphilic (both lipophilic and hydrophilic), their sorption and accumulation behaviors differ from those of neutral organic and common ionic compounds. In this review, we discuss processes affecting the availability of PFASs in soil after analyzing the potential mechanisms underlying the sorption and uptake of PFASs in the soil–plant system. We also summarize the current knowledge on root uptake and translocation of PFASs in plants. We found that the root concentration factor of PFASs for plants grown in soil was not significantly correlated with hydrophobicity, whereas the translocation factor was significantly and negatively correlated with PFAS hydrophobicity regardless of whether plants were grown hydroponically or in soil. Further research on the cationic, neutral, and zwitterionic forms of diverse PFASs is urgently needed to comprehensively understand the environmental fates of PFASs in the soil–plant system. Additional research directions are suggested, including the development of more accurate models and techniques to evaluate the bioavailability of PFASs, the effects of root exudates and rhizosphere microbiota on the bioavailability and plant uptake of PFASs, and the roles of different plant organelles, lipids, and proteins in the accumulation of PFASs by plants.

Organophosphate esters (OPEs) are normally used as flame retardants, plasticizers and lubricants, but have become environmental pollutants. Because OPEs are normally present alongside heavy metals in soils, the effects of interactions between OPEs and heavy metals on plant uptake of OPEs need to be determined. In this study, we investigated the effects of OPEs chemical structure, plant cultivar and copper (Cu) on the uptake and translocation of OPEs by plants. The bioaccumulation of OPEs varied among plant cultivars. They were preferentially enriched in carrot, with the lowest concentrations observed in maize. OPEs with electron-ring substituents (ER-OPEs) exhibited a higher potential for root uptake than did OPEs with open-chain substituents (OC-OPEs), which could be attributed to the higher sorption of ER-OPEs onto root charged surfaces. This was explained by the stronger noncovalent interactions with the electron-rich structure of ER-OPEs. The presence of Cu slightly reduced the distinct difference in the ability of roots to take up OC-OPEs and ER-OPEs. This was explained by the interactions of Cu ions with the electron-rich structure of ER-OPEs, which suppressed the sorption of ER-OPEs on the root surface. A negative relationship between the logarithms of the translocation factor and octanol-water partition coefficient (Kow) was observed in treatments with either OPEs only or OPEs + Cu, implying the significant role of hydrophobicity in the OPEs acropetal translocation. The results will improve our understanding of the uptake and translocation of OPEs by plant cultivars as well as how the process is affected by the chemical structure of OPEs and Cu, leading to improvements in the ecological risk assessment of OPEs in the food chain.

Aspergillus subgenus Nidulantes includes species with emericella-like ascomata and asexual species. Subgenus Nidulantes is the second largest subgenus of Aspergillus and consists of nine sections. In this study, agricultural soils were sampled from 12 provinces and autonomous regions in China. Based on primary BLAST analyses, seven of 445 Aspergillus isolates showed low similarity with existing species. A polyphasic investigation, including phylogenetic analysis of partial ITS, β-tubulin, calmodulin, and RNA polymerase II second largest subunit genes, provided evidence that these isolates were distributed among four new species (Aspergillus guangdongensis, A. guangxiensis, A. sichuanensis and A. tibetensis) in sections Aenei, Ochraceorosei, and Sparsi of subgenus Nidulantes. Illustrated morphological descriptions are provided for each new taxon.

Wastewater treatment plants (WWTPs) are the main hotspots for the release of antibiotics, including the widely used sulphonamides. Microbes play important roles in eliminating sulphonamides in WWTPs, and knowledge about these degraders and their interactions within the microbial community is crucial for operating and optimising WWTPs. In the present study, stable isotope probing (SIP) coupled with high-throughput sequencing as culture-independent approach revealed four operational taxonomic units (OTUs) involved in sulphamethoxazole (SMX) degradation in activated sludge. Except for the OTU affiliated with Gammaproteobacteria, the others have not been previously reported to possess the ability to metabolise SMX. The isolated SMX degrader by culture-dependent method did not participate in SMX biodegradation in situ according to the SIP analysis, and showed weak correlations with other members in the activated sludge. The complex interactions between in situ active SMX degraders and non-degrading microbes might explain our failure to isolate these degraders. In addition, sul1 genes associated with SMX resistance were also labelled with 13C, suggesting that they might benefit from SMX degradation and/or originate from the active SMX degraders. These findings broaden our understanding of the diversity of SMX-degrading microbes and their associated characteristics in WWTPs. Keywords: Antibiotic resistance genes, Activated sludge, Sulphamethoxazole-degrading bacteria, Molecular ecological network analysis, Stable isotope probing, Sulphonamide biodegradation

Autochthonous bioaugmentation (ABA) strategies are primarily carried out using a single, highly efficient type of bacteria that is capable of directly degrading the target compound. However, no studies have examined the use of non-direct degraders (NDDs), which are involved in the metabolic pathway of target compounds instead of direct degradation. Here, to evaluate the bioremediation efficiency and mechanism of ABA by NDDs, we demonstrated the use of an NDD on the biodegradation of biphenyl, a model compound used to study polychlorinated biphenyl (PCB) degradation. The NDD examined in this study, Marmoricola LJ-33, was isolated from activated sludge. Although Marmoricola LJ-33 alone did not directly degrade biphenyl under laboratory conditions, it did contribute to in situ biphenyl biodegradation in the activated sludge, as evidenced by DNA-stable-isotope-probing (DNA-SIP). Implementation of ABA with strain LJ-33 was shown to significantly accelerate biphenyl degradation efficiency, demonstrating the potential of NDD strains for degradation in ABA. More importantly, LJ-33 amendment altered the diversity of the microbial communities involved in biphenyl metabolism. Our findings suggest that a combination of pre-screening followed by DNA-SIP analysis is a practical strategy to precisely separate NDDs. Additionally, our work indicates a new mechanism of ABA strategy with NDDs as a promising in situ bioremediation strategy, broadening our concept in constructing functional consortia to enhance the biodegradation performance of activated sludge in wastewater treatment plants. Keywords: Autochthonous bioaugmentation (ABA), Non-direct degraders (NDDs), Stable isotope probing (SIP), Pre-screening, bphC gene

Summary: Dysregulated alternative splicing events have been implicated in many types of cancer, but the underlying molecular mechanisms remain unclear. Here, we observe that the splicing factor SRSF1 regulates DBF4B exon6 splicing by specifically binding and promoting its inclusion. Knockdown of the exon6-containing isoform (DBF4B-FL) significantly inhibits the tumorigenic potential of colon cancer cells in vitro and in mice, and SRSF1 inactivation phenocopies DBF4B-FL depletion. DBF4B-FL and SRSF1 are required for cancer cell proliferation and for the maintenance of genomic stability. Overexpression of DBF4B-FL can protect against DNA damage induced by SRSF1 knockdown and rescues growth defects in SRSF1-depleted cells. Increased DBF4B exon6 inclusion parallels SRSF1 upregulation in clinical colorectal cancer samples. Taken together, our findings identify SRSF1 as a key regulator of DBF4B pre-mRNA splicing dysregulation in colon cancer, with possible clinical implications as candidate prognostic factors in cancer patients. : Chen et al. find that SRSF1 is a key regulator of DBF4B pre-mRNA splicing in colon cancer cells and demonstrates that SRSF1 prevents DNA damage and promotes tumorigenesis through its regulation of a DBF4B-FL splice variant.

Plant pathogens are increasingly considered as important agents in promoting plant coexistence, while plant symbionts like ectomycorrhizal fungi (EMF) can facilitate plant dominance by helping conspecific individuals to defend against plant pathogens. However, we know little about their relationships with plants at large scales. Here, using soil fungal data collected from 28 forest reserves across China, we explored the latitudinal diversity gradients of overall fungi and different fungal functional guilds, including putative plant pathogens, EMF, and saprotrophic fungi. We further linked the spatial patterns of alpha diversities of putative plant pathogens and EMF to the variation of plant species richness. We found that the relationships between latitude and alpha diversities of putative plant pathogens and EMF were region-dependent with sharp diversity shifts around the mid-latitude (~35°N), which differed from the unimodal diversity distributions of the overall and saprotrophic fungi. The variations in the diversities of putative plant pathogens and EMF were largely explained by the spatial regions (south vs. north/subtropical zone vs. temperate zone). Additionally, the alpha diversities of these two fungal guilds exhibited opposing trends across latitude. EMF could alter the relationship between diversities of putative plant pathogens and plants in the south/subtropical region, but not vice versa. We also found that the ratio of their alpha diversities (EMF to putative plant pathogens) was negatively related to plant species richness across the spatial regions (north to south), and explained ~10% of the variation of plant species richness. Overall, our findings suggest that plant-microbe interactions not only shape the local plant diversity but also may have non-negligible contributions to the large-scale patterns of plant diversity in forest ecosystems.

We propose an optimum distance search method for realizing high-quality computational ghost imaging (CGI). The proposed method, which utilizes the advantages of compressive sensing and the CGI technique, is composed of two search steps. The first step is a coarse search, and the second is a fine search. By using the two-step search, an optimum distance can be obtained. The signal-to-noise ratio (SNR) and the relative mean square error (RMSE) are used as criteria during the search process. Both simulation and experimental results demonstrate that the proposed method can enhance imaging quality, and compressive CGI is more sensitive to distance variations than traditional CGI. The SNR and RMSE are improved when the object is at the optimum distance.

Alternative splicing is a major mechanism of controlling gene expression and protein diversity in higher eukaryotes. We report that the splicing factor SRSF10 functions during striated muscle development, myoblast differentiation, and glucose production both in cells and in mice. A combination of RNA-sequencing and molecular analysis allowed us to identify muscle-specific splicing events controlled by SRSF10 that are critically involved in striated muscle development. Inclusion of alternative exons 16 and 17 of Lrrfip1 is a muscle-specific event that is activated by SRSF10 and essential for myoblast differentiation. On the other hand, in mouse primary hepatocytes, PGC1α is a key target of SRSF10 that regulates glucose production by fasting. SRSF10 represses inclusion of PGC1α exon 7a and facilitates the production of functional protein. The results highlight the biological significance of SRSF10 and regulated alternative splicing in vivo.

We develop an adaptive differential correspondence imaging (CI) method using a sorting technique. Different from the conventional CI schemes, the bucket detector signals (BDS) are first processed by a differential technique, and then sorted in a descending (or ascending) order. Subsequently, according to the front and last several frames of the sorted BDS, the positive and negative subsets (PNS) are created by selecting the relative frames from the reference detector signals. Finally, the object image is recovered from the PNS. Besides, an adaptive method based on two-step iteration is designed to select the optimum number of frames. To verify the proposed method, a single-detector computational ghost imaging (GI) setup is constructed. We experimentally and numerically compare the performance of the proposed method with different GI algorithms. The results show that our method can improve the reconstruction quality and reduce the computation cost by using fewer measurement data.

Microorganisms responsible for the degradation of phenanthrene in a clean forest soil sample were identified by DNA-based stable isotope probing (SIP). The soil was artificially amended with either 12C- or 13C-labeled phenanthrene, and soil DNA was extracted on days 3, 6 and 9. Terminal restriction fragment length polymorphism (TRFLP) results revealed that the fragments of 219- and 241-bp in HaeIII digests were distributed throughout the gradient profile at three different sampling time points, and both fragments were more dominant in the heavy fractions of the samples exposed to the 13C-labeled contaminant. 16S rRNA sequencing of the 13C-enriched fraction suggested that Acidobacterium spp. within the class Acidobacteria, and Collimonas spp. within the class Betaproteobacteria, were directly involved in the uptake and degradation of phenanthrene at different times. To our knowledge, this is the first report that the genus Collimonas has the ability to degrade PAHs. Two PAH-RHDα genes were identified in 13C-labeled DNA. However, isolation of pure cultures indicated that strains of Staphylococcus sp. PHE-3, Pseudomonas sp. PHE-1, and Pseudomonas sp. PHE-2 in the soil had high phenanthrene-degrading ability. This emphasizes the role of a culture-independent method in the functional understanding of microbial communities in situ.