Membrane distillation (MD) displays superior characteristics to other technologies to alleviate the ever-increasing freshwater crisis through seawater desalination and/or wastewater recycling. ...However, the critical challenge in MD is fabricating high-performance membranes. In this study, we fabricated a high-performance hierarchical fibrous composite (HFC) membrane to acquire a high water flux while maintaining a high salt rejection for MD. This HFC membrane comprises of a thin active dense layer with small poly (vinylidene fluoride-
co
-hexafluoropropylene) (PH) nanofibers to allow maximum mass transfer and a thick support layer with large poly(ethylene terephthalate) (PET) microfibers to give minimum heat transfer. By tailoring the structures of both the active and support layers to reduce the trade-off between the mass transfer and heat transfer during the MD process, the optimized HFC membrane, having a 3 μm thick PH active layer and 70 μm thick PET support layer, achieved the highest reported water flux of 79.21 ± 4.17 L m
−2
h
−1
and the salt rejection was higher than 99.9% using 3.5 wt% NaCl as the feed under a temperature difference of 40 °C in direct contact membrane distillation (DCMD). Our study describes a novel HFC membrane which demonstrates great achievements in elevating the MD performance.
Mammalian retinoic acid-inducible gene I (RIG-I)-like receptors detect viral double-stranded RNA (dsRNA) and 5'-triphosphorylated RNA to activate the transcription of interferon genes and promote ...antiviral defense. The
RIG-I-like receptor DRH-1 promotes defense through antiviral RNA interference (RNAi), but less is known about its role in regulating transcription. Here, we describe a role for DRH-1 in directing a transcriptional response in
called the intracellular pathogen response (IPR), which is associated with increased pathogen resistance. The IPR includes a set of genes induced by diverse stimuli, including intracellular infection and proteotoxic stress. Previous work suggested that the proteotoxic stress caused by intracellular infections might be the common trigger of the IPR, but here, we demonstrate that different stimuli act through distinct pathways. Specifically, we demonstrate that DRH-1/RIG-I is required for inducing the IPR in response to Orsay virus infection but not in response to other triggers like microsporidian infection or proteotoxic stress. Furthermore, DRH-1 appears to be acting independently of its known role in RNAi. Interestingly, expression of the replication-competent Orsay virus RNA1 segment alone is sufficient to induce most of the IPR genes in a manner dependent on RNA-dependent RNA polymerase activity and on DRH-1. Altogether, these results suggest that DRH-1 is a pattern recognition receptor that detects viral replication products to activate the IPR stress/immune program in
lacks homologs of most mammalian pattern recognition receptors, and how nematodes detect pathogens is poorly understood. We show that the
RIG-I homolog DRH-1 mediates the induction of the intracellular pathogen response (IPR), a novel transcriptional defense program, in response to infection by the natural
viral pathogen Orsay virus. DRH-1 appears to act as a pattern recognition receptor to induce the IPR transcriptional defense program by sensing the products of viral RNA-dependent RNA polymerase activity. Interestingly, this signaling role of DRH-1 is separable from its previously known role in antiviral RNAi. In addition, we show that there are multiple host pathways for inducing the IPR, shedding light on the regulation of this novel transcriptional immune response.
Abstract
Global climate change has led to a significant increase in the frequency of extreme rainfall events in the Qinghai-Tibetan Plateau (QTP), thus potentially increasing the annual rainfall ...amounts and, consequently, affecting the net soil nitrogen (N) mineralization process. However, few studies on the responses of the soil net N mineralization rates to the increases in rainfall amounts and frequencies in alpine wet meadows have been carried out. Therefore, the present study aims to assess the effects of rainfall frequency and amount changes on the N fixation capacity of wet meadow soils by varying the rainfall frequency and amount in the Gahai wet meadow in the northeastern margin of the QTP during the plant-growing season in 2019. The treatment scenarios consisted of ambient rain (CK) and supplementary irrigation at a rate of 25 mm, with different irrigation frequencies, namely weekly (DF1), biweekly (DF2), every three weeks (DF3), and every four weeks (DF4). According to the obtained results, the increased rainfall frequency and amount decreased the soil mineral N stock and increased the aboveground vegetation biomass (AB) amounts and soil water contents in the wet meadows of the QTP. Ammonium (NH
4
+
-N) and nitrate N (NO
3
–
-N) contributed similarly to the mineral N contents. However, the ammonification process played a major role in the soil mineralization process. The effects of increasing rainfall amount and frequency on N mineralization showed seasonal variations. The N mineralization rate showed a single-peaked curve with increasing soil temperature during the rapid vegetation growth phase, reaching the highest value in August. In addition, the N mineralization rates showed significant positive correlations with soil temperatures and NH
4
+
-N contents and a significant negative correlation with AB (
P
< 0.05). The results of this study demonstrated the key role of low extreme rainfall event frequencies in increasing the net soil N mineralization rates in the vegetation growing season, which is detrimental to soil N accumulation, thereby affecting the effectiveness of soil N contents.
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•The spatial data analysis model and machine learning algorithm were comprehensively applied at the town scale.•Interannual variation in the ESV first decreased and then increased; ...LUI and elevation were the most important drivers.•There was a negative spatial effect between the ESV and CUI; average CCD of the ESV and CUI is increasing.
Urbanization is a key factor that threatens the stability of ecosystem services (ESs), which are crucial for maintaining ecological security and enhancing human quality of life. Gaining insight into the spatiotemporal differentiation of the ecosystem service value (ESV) and its coupling relationship with urbanization is a key issue in promoting sustainable regional development. We employed various algorithms, including the improved equivalence factor method, random forest model, mixed geographically and temporally weighted regression model, and coupling coordination degree (CCD) model, to reveal the spatiotemporal evolution of the ESV and its driving mechanisms in the Lanzhou-Xining urban agglomeration (LXUA) from 1980 to 2020. In addition, we explored the coupling relationship between ESV and the combined urbanization index (CUI). The results showed the following: (1) From 1980 to 2020, the interannual variation in ESV first decreased and then increased, with an increase of 230 million yuan/annum in 2020 compared to that of 1980. Spatially, the ESV exhibits a distribution pattern of high in the south and low in the north, and high in the west and low in the east. (2) Land use intensity (LUI) and elevation contributed degree values exceeding 20% to the ESV and were the most important drivers of the ESV. (3) From 1980 to 2020, the average CCD values of the ESV and CUI transitioned from being severely unbalanced (0.19) to being slightly balanced (0.42). There was a negative spatial correlation between the ESV and CUI, with each cluster type was distributed discretely in space. Our study emphasizes that in areas characterized by robust ecosystem integrity and a high ESV, the increase in LUI was constitutes the main reason for the decline in the ESV. The findings of this study can provide a scientific basis for the coordinated development of ESVs and urbanization in the LXUA and other cities.
Although cancer genomes are replete with noncoding mutations, the effects of these mutations remain poorly characterized. Here we perform an integrative analysis of 930 tumor whole genomes and ...matched transcriptomes, identifying a network of 193 noncoding loci in which mutations disrupt target gene expression. These 'somatic eQTLs' (expression quantitative trait loci) are frequently mutated in specific cancer tissues, and the majority can be validated in an independent cohort of 3,382 tumors. Among these, we find that the effects of noncoding mutations on DAAM1, MTG2 and HYI transcription are recapitulated in multiple cancer cell lines and that increasing DAAM1 expression leads to invasive cell migration. Collectively, the noncoding loci converge on a set of core pathways, permitting a classification of tumors into pathway-based subtypes. The somatic eQTL network is disrupted in 88% of tumors, suggesting widespread impact of noncoding mutations in cancer.
Objective Gastric cancer (GC) remains difficult to cure due to heterogeneity in a clinical challenge and the molecular mechanisms underlying this disease are complex and not completely understood. ...Accumulating evidence suggests that microRNAs (miRNAs) play an important role in GC, but the role of specific miRNAs involved in this disease remains elusive. We performed next generation sequencing (NGS)-based whole-transcriptome profiling to discover GC-specific miRNAs, followed by functional validation of results. Design NGS-based miRNA profiles were generated in matched pairs of GCs and adjacent normal mucosa (NM). Quantitative RT-PCR validation of miR-29c expression was performed in 274 gastric tissues, which included two cohorts of matched GC and NM specimens. Functional validation of miR-29c and its gene targets was undertaken in cell lines, as well as K19-C2mE and K19-Wnt1/C2mE transgenic mice. Results NGS analysis revealed four GC-specific miRNAs. Among these, miR-29c expression was significantly decreased in GC versus NM tissues (p<0.001). Ectopic expression of miR-29c mimics in GC cell lines resulted in reduced proliferation, adhesion, invasion and migration. High miR-29c expression suppressed xenograft tumour growth in nude mice. Direct interaction between miR-29c and its newly discovered target, ITGB1, was identified in cell lines and transgenic mice. MiR-29c expression demonstrated a stepwise decrease in wild type hyperplasia-dysplasia cascade in transgenic mice models of GC. Conclusions MiR-29c acts as a tumour suppressor in GC by directly targeting ITGB1. Loss of miR-29c expression is an early event in the initiation of gastric carcinogenesis and may serve as a diagnostic and therapeutic biomarker for patients with GC.
The dominant paradigm for HPV carcinogenesis includes integration into the host genome followed by expression of E6 and E7 (E6/E7). We explored an alternative carcinogenic pathway characterized by ...episomal E2, E4, and E5 (E2/E4/E5) expression. Half of HPV positive cervical and pharyngeal cancers comprised a subtype with increase in expression of E2/E4/E5, as well as association with lack of integration into the host genome. Models of the E2/E4/E5 carcinogenesis show p53 dependent enhanced proliferation in vitro, as well as increased susceptibility to induction of cancer in vivo. Whole genomic expression analysis of the E2/E4/E5 pharyngeal cancer subtype is defined by activation of the fibroblast growth factor receptor (FGFR) pathway and this subtype is susceptible to combination FGFR and mTOR inhibition, with implications for targeted therapy.
The high level of accuracy and sensitivity of next generation sequencing for quantifying genetic material across organismal boundaries gives it tremendous potential for pathogen discovery and ...diagnosis in human disease. Despite this promise, substantial bacterial contamination is routinely found in existing human-derived RNA-seq datasets that likely arises from environmental sources. This raises the need for stringent sequencing and analysis protocols for studies investigating sequence-based microbial signatures in clinical samples.
Although promoter-associated CpG islands have been established as targets of DNA methylation changes in cancer, previous studies suggest that epigenetic dysregulation outside the promoter region may ...be more closely associated with transcriptional changes. Here we examine DNA methylation, chromatin marks, and transcriptional alterations to define the relationship between transcriptional modulation and spatial changes in chromatin structure. Using human papillomavirus-related oropharyngeal carcinoma as a model, we show aberrant enrichment of repressive H3K9me3 at the transcriptional start site (TSS) with methylation-associated, tumor-specific gene silencing. Further analysis identifies a hypermethylated subtype which shows a functional convergence on MYC targets and association with CREBBP/EP300 mutation. The tumor-specific shift to transcriptional repression associated with DNA methylation at TSSs was confirmed in multiple tumor types. Our data may show a common underlying epigenetic dysregulation in cancer associated with broad enrichment of repressive chromatin marks and aberrant DNA hypermethylation at TSSs in combination with MYC network activation.
Abstract
As one of the important greenhouse gas, nitrous oxide (N
2
O) has attracted much attention globally under climate change context. Agricultural practices are the main sources of greenhouse ...gas emissions. Nevertheless, scarcity of literature is available on the effects of different tillage measures on soil N
2
O emission under spring wheat (
Triticum aestivum L.
) ecosystem in the semi-arid area of the Loess Plateau. The main objective of the experimental study was to explore the influence of conservation tillage techniques on soil physicochemical properties, nitrous oxide emission and yield in the Northern semi-arid Dingxi region of China. Four treatments viz
.,
conventional tillage (CT), no tillage (NT), straw mulch with conventional tillage (TS) and stubble-return with no-till (NTS) were evaluated under randomized complete block design with three replications. Our results depicted that compared with conventional tillage, bulk density and water content of topsoil was increased and soil pH value was reduced under conservation tillage techniques. Conservation tillage NT, TS and NTS increased organic carbon, TN, MBN and NH
4
+
-N and reduced the accumulation of NO
3
–
N. Additionally, although the N
2
O emission under NT, TS and NTS was 8.95, 41.90 and 21.05% respectively higher than under T treatment, the corresponding wheat yield was 15.40, 31.97 and 63.21% higher than T treatment. Moreover, correlation analysis showed that soil moisture and temperature were the most significant factors affecting soil N
2
O emission. The NTS treatment pointedly increased crop yield without significantly increasing soil N
2
O emission. Consequently, based on economic and environmental benefits and considering N
2
O emission and crop yield, we suggest that NTS technique is the best conservation tillage strategy in the semi-arid environmental zone of the Loess Plateau of Dingxi China.
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