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Biochar is widely used as a soil amendment in green roofs because it can increase the soil's water-holding capacity, inhibit cracking, and provide nutrients for vegetation. The interaction mechanism between biochar and expansive soil is a significant factor in the performance of green roofs. However, research mainly focused on the hydrological scale (i.e. runoff regulation and rainwater storage), and there is a lack of research on the hydrological properties (i.e. hysteresis of soil–water characteristic curves, changes in soil pore size and pore distribution, formation and development of cracks and swelling–shrinking characteristics) of biochar-amended expansive soils under dynamic water environment. This test was conducted out on soil columns with expansive soil and 5% (by mass) biochar-amended under 5 drying–wetting cycles. The results showed that within the range of water content suitable for plant growth (i.e. between the anaerobic point and wilting point), the hysteresis area of soil–water characteristic curves of the amended soil is smaller than the bare soil at each drying–wetting cycle. The addition of biochar changes the pore size distribution of the soil, reduces the pore size and swelling–shrinking characteristics of the expansive soil, and inhibits the development of cracks. Therefore, the addition of biochar significantly attenuates the hysteresis characteristics of the soil–water characteristic curves of expansive soils, which may improve the stability of the hydraulic performance of green roofs. The results contribute to the understanding of the physicochemical and water properties of biochar-amended expansive soil and provide theoretical support for the application of biochar to green roofs. [ABSTRACT FROM AUTHOR]

The Channa argus (C. argus), an important cultured freshwater species, is widely distributed in China, which possesses the characteristic of high disease resistance. However, the information on genomic and transcriptomic studies on disease resistance of this species is not available at present. To address the shortfall and to better understand snakehead immune response to pathogen infection at molecular level, the C. argus were challenged with potent Aeromonas veronii (A. veronii) for 24 h and the high-throughput RNA sequencing (RNA-seq) technology was employed to produce transcriptomes from the liver. Firstly, the serum parameters were significantly changed after Aeromonas veronii infection for 24 h compared with the control group. Thus, an average of 326,557,262 clean reads obtained were de novo assembled into 157,766 unigenes with most of the unigenes between 201 and 500 bp. All of unigenes were annotated to six public databases (Nr, Swiss-Prot, COG, GO, KEGG, and Pfam). A total of 21,217 differentially expressed unigenes (DEGs) were identified. The 21,217 DEGs were significantly enriched in 16 pathways related to the immune or disease. Finally, the expression levels of six selected immune-related DEGs were scrutinized. Three genes encoding TNF-α, IL-1β, and Bcl2 were significantly upregulated, whereas the gene encoding MyD88, NOD-1, and NOD-2 was significantly downregulated. In summary, this study provides valuable transcriptome resource for understanding the defense mechanisms of C. argus in resistance to pathogens from the gene expression viewpoint, which also open up the possibility to study the immune complexity and to better comprehend the interrelationships between some immune pathways in C. argus. [ABSTRACT FROM AUTHOR]

Large deformation is a crucial factor in deep-buried tunnels constructed through soft rocks with a high geostress. Taking the deep-buried Baozhen tunnel through layered shale as an example, this study investigated its large deformation characteristics and the support countermeasures. Two study sections located in horizontally bedded carbonaceous shale and inclined bedded arenaceous shale were considered. First, the large deformation characteristics of normal sections were explored. Subsequently, a series of laboratory tests were conducted to investigate the mechanical properties and failure behavior of the shales in these sections. Based on the tested constitutive parameters considering the contact properties, the feasibility of optimization schemes related to the two sections was verified using the UDEC numerical software. Finally, the field monitoring results from the test sections, including the tunnel convergence, deep deformation, surrounding rock pressure and normal pressure on the secondary lining, were presented to further investigate the control effects of the optimization schemes. Both the numerical simulation and field monitoring results showed that the asymmetrically large deformation of the Baozhen tunnel could be attributed to the combined effect of the layered soft rock and the shear stress under high geostress. The invert rockbolts not only prevented the invert arch from heaving, but also helped reduce the global convergence of the tunnel. Tunneling through inclined bedded rocks was associated with a significant unsymmetrical-loading effect, and an asymmetric arrangement of the rockbolts could effectively deal with this issue; thus, the normal pressures acting on the surface of the support structures were more uniformly distributed. The research results provide references for the support design of deep-buried tunnels in layered rock masses. Highlights: Large deformation characteristics of Baozhen tunnel are explored. Failure behavior of layered shales is investigated. Effect of inverted rockbolts on tunnel deformation is demonstrated. Asymmetric rockbolt arrangement is effective in inclined bedded rock. [ABSTRACT FROM AUTHOR]

Rainfall-induced shallow landslides and debris flows are one of the most common erosion process and primary channel initiation mechanisms in many steep landscapes. Their initiation conditions are physically controlled by the soil properties and topographically influenced by the competition between area- (A) and slope-dependent (S) sediment transport process. In this work, the A-S relationship of landslides in two forests was compared with respect to the physical properties of soil and plant roots. The results reveal that landslides in the Pinus tabuleaformis forest commonly have larger surface- and contributing area, deeper failure plane and gentler slope gradient than those in the Larix Kaemphferi forest. The saturated hydraulic conductivity in the Pinus tabuleaformis forest is higher and strongly correlates to plant root biomass. The effective cohesion and inner frictional angle of soil mass in the two forests are similar. Faster saturated hydraulic conductivity may lead to the higher upslope contributing area of landslides in the the Pinus tabuleaformis forest. A combination of finite-slope model and precipitation interception model reveals that landslides in the Pinus tabuleaformis forest require higher rainfall amount that those in the Larix Kaemphferi forest. Last but not least, this work provides a clue that strong root network and high saturated hydraulic conductivity may promote the A-S condition. [ABSTRACT FROM AUTHOR]

Mendelian randomization (MR) is attracting considerable critical attention. This paper aimed to explore the characteristics of the publications of MR, to reach an insight in this field and prospect the future trend. A bibliometric analysis was performed to identify published MR-related research. The articles were selected from the Web of Science Core Collection database. Excel 2019, VOSviewer 1.6.9, and CiteSpace 5.7.R3 were used to analyze the information. A total of 1783 papers of MR were identified, and the first included literature appeared in 2003. A total of 2829 institutions from 72 countries participated in the relevant research, while the UK contributed to 852 articles and were in a leading position. The most productive institution was the University of Bristol, and Smith GD who has posted the most articles (n=202) was also from there. The Int J Epidemiol (100 publications, 6861 citations) was the most prolific and high citation journal. Related topics of frontiers will still focus on coronary heart disease, diabetes, cancer, psychiatric disorder, body mass index, and lifestyle factors. We summarized the publication information of MR-related literature from 2003 to 2020, including country and institution of origin, authors, and publication journal. We analyzed former research hotspots in the field of MR and predicted future areas of interest. Exposures and outcomes detected in this paper will be the hotspots and frontiers of research in the next few years. [ABSTRACT FROM AUTHOR]

Loss Plateau of China is an area with long-term vegetation restoration while serious mass movements. Local vegetation does act as sediment reducing role while quantification of their effect on landslides is lacking. This work presents a first research work about the connection between landslides and vegetation by the example of July 25–26, 2013, extreme rainstorm. High-resolution sensing orthoimages, landside width, and simplified infinite slope theory were used to examine landslide distribution and the lateral apparent cohesion of roots. The results reveal that shallow landslides have a higher probability at the transitional slope area. The majority of them have a gradient of 20–25°, locate on south-facing slopes, and areas with sparse vegetation. Vegetation cover, represented by the Green-Red Vegetation Index (GRVI), is the controlling factor of landslide distribution and size. The estimated lateral apparent cohesion of plant roots is not positively related to GRVI, and increase when GRVI > 0.2. The relationship between landslide width and slope gradient indicates that strong root strength may result in larger landslide volume. This result of this work is a pioneering trial in correlating the lateral apparent cohesion from roots and forest crown, which is helpful for understanding the effect of vegetation on landslides. [ABSTRACT FROM AUTHOR]

Plant roots positively and negatively contribute to hillslope stability by the perspective of soil strength and water flow infiltration improvement. To further examine the controversy, this work addresses the six root architecture types on the rainfall threshold for slope stability by tests of saturated conductivity and shear strength of the root-soil composite. An infinite slope model and a 1D flow model combine to obtain the rainfall intensity-duration threshold of slope failure. The results reveal that the saturated hydraulic conductivity of root-soil composite is 1 to 4.23 times of bare soil, which increases as the length density, volume density, and volume fractal dimension of plant roots. Furthermore, plant roots can enhance the cohesion and angle of internal friction by 35.19–81.79% and 12.92–42.36%, respectively. Finally, the R-type and V-type roots have the most effective root architecture for hillslope stability. In the process of afforestation, H-type may be suitable for areas with soft slope, while V-type and R-type may be suitable for steep slopes. The results of this work present an interesting study on the interaction of plant roots on slope stability, which is worthy of further study in the future. [ABSTRACT FROM AUTHOR]

Several meta-analyses have evaluated the value of biomarkers in diagnosing breast cancer, but which biomarker has the optimal diagnostic value remains unclear. This overview aimed to compare the accuracy of different biomarkers in diagnosing breast cancer. PubMed, Embase.com, the Cochrane Library of Systematic Reviews, and Web of Science were searched. The assessment of multiple systematic reviews-2 (AMSTAR-2) was used to assess the methodological quality and preferred reporting items for a systematic review and meta-analysis of diagnostic test accuracy (PRISMA-DTA) for reporting quality. Pairwise meta-analyses were performed to estimate the pooled results for each biomarker, and indirect comparisons were conducted to compare diagnostic accuracy between biomarkers. Eleven systematic reviews (SRs) involving 218 original studies were included. All SRs were of critically low methodological quality, 3 SRs had minimal reporting flaws and 8 SRs had minor flaws. The pooled sensitivity and specificity were 0.77 and 0.87 for miRNA, 0.70 and 0.87 for circulating cell-free DNA, 0.29 and 0.96 for APC gene promoter methylation, 0.69 and 0.99 for 14-3-3σ promoter methylation, 0.63 and 0.82 for CA153, 0.58 and 0.87 for CEA, and 0.73 and 0.56 for PSA. Compared with CA153 and PSA, miRNA had a higher sensitivity and specificity. The sensitivity of miRNA was higher than circulating cell-free DNA and CEA, although they had the same specificities. APC gene promoter methylation and 14-3-3σ promoter methylation were more specific than miRNA, but they had unacceptably low sensitivity. In conclusion, miRNA had better diagnostic accuracy than the other six biomarkers. But due to the low quality of included SRs, the results need to be interpreted with caution. Further study should investigate the diagnostic accuracy of different biomarkers in direct comparisons and focus on the value of combined biomarkers. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the toxic effects on bioaccumulation, oxidative stress, immune responses and immune-related genes expression of Channa argus exposed for 28 days with waterborne selenium (0, 50, 100, 200, and 400 µg/L). After 28 days, the order of Se accumulation in tissues was kidney > liver > spleen > intestine > gill > muscle. Antioxidant parameters in liver and spleen of C. argus evidenced an oxidative stress condition in waterborne selenium. In addition, immunological parameters and immune-related gene expression were all enhanced with an increase in Se expose levels. Our results suggest that waterborne Se exposure can induce considerable Se accumulation, oxidative stress and immunotoxic effects on C. argus. [ABSTRACT FROM AUTHOR]

In this work, we explore the ability of several characterization approaches for phenotyping to extract information about plant cell wall properties in diverse maize genotypes with the goal of identifying approaches that could be used to predict the plant's response to deconstruction in a biomass-to-biofuel process. Specifically, a maize diversity panel was subjected to two high-throughput biomass characterization approaches, pyrolysis molecular beam mass spectrometry (py-MBMS) and near-infrared (NIR) spectroscopy, and chemometric models to predict a number of plant cell wall properties as well as enzymatic hydrolysis yields of glucose following either no pretreatment or with mild alkaline pretreatment. These were compared to multiple linear regression (MLR) models developed from quantified properties. We were able to demonstrate that direct correlations to specific mass spectrometry ions from pyrolysis as well as characteristic regions of the second derivative of the NIR spectrum regions were comparable in their predictive capability to partial least squares (PLS) models for p-coumarate content, while the direct correlation to the spectral data was superior to the PLS for Klason lignin content and guaiacyl monomer release by thioacidolysis as assessed by cross-validation. The PLS models for prediction of hydrolysis yields using either py-MBMS or NIR spectra were superior to MLR models based on quantified properties for unpretreated biomass. However, the PLS models using the two high-throughput characterization approaches could not predict hydrolysis following alkaline pretreatment while MLR models based on quantified properties could. This is likely a consequence of quantified properties including some assessments of pretreated biomass, while the py-MBMS and NIR only utilized untreated biomass. [ABSTRACT FROM AUTHOR]

The PTEN tumor suppressor is a lipid phosphatase that has a central role in regulating the phosphatidylinositol-3-kinase (PI3K) signal transduction cascade. Nevertheless, the mechanism by which the PTEN activity is regulated in cells needs further elucidation. Although previous studies have shown that ubiquitination of PTEN can modulate its stability and subcellular localization, the role of ubiquitination in the most critical aspect of PTEN function, its phosphatase activity, has not been fully addressed. Here, we identify a novel E3 ubiquitin ligase of PTEN, Ret finger protein (RFP), that is able to promote atypical polyubiquitinations of PTEN. These ubiquitinations do not lead to PTEN instability or relocalization, but rather significantly inhibit PTEN phosphatase activity and therefore modulate its ability to regulate the PI3K signal transduction cascade. Indeed, RFP overexpression relieves PTEN-mediated inhibitory effects on AKT activation; in contrast, RNAi-mediated knockdown of endogenous RFP enhances the ability of PTEN to suppress AKT activation. Moreover, RFP-mediated ubiquitination of PTEN inhibits PTEN-dependent activation of TRAIL expression and also suppresses its ability to induce apoptosis. Our findings demonstrate a crucial role of RFP-mediated ubiquitination in controlling PTEN activity. [ABSTRACT FROM AUTHOR]

Besides transcription regulation, gene expression is also regulated at translation level. Although translation regulation is mainly mediated by translation initiation, an abundance of evidence shows that the termination phase of translation is also important for gene expression. The expression of λN gene is down regulated at translation level in L24 mutant, however the precise mechanism still remains unknown. We report here that in an L24 mutant strain, the expression of lac- λN and GST- λN is decreased to 25% and 50% of that in wild type T83 strain respectively. Strikingly, the yield of GST- λN fusion protein in L24 mutant can be restored to the level as in T83 wild type strain by changing the two codons upstream λN stop codon. These findings imply that the stop codon and its context are involved in the translation regulation. The possible reason is that the translation termination complex containing L24 mutant ribosome may not dissociate properly in stop code region. This failure of disengagement from mRNA will slow down the process of following ribosomes, and consequently decrease the efficiency of λN gene expression. [ABSTRACT FROM AUTHOR]

The p53 tumour suppressor is a short-lived protein that is maintained at low levels in normal cells by Mdm2-mediated ubiquitination and subsequent proteolysis. Stabilization of p53 is crucial for its tumour suppressor function. However, the precise mechanism by which ubiquitinated p53 levels are regulated in vivo is not completely understood. By mass spectrometry of affinity-purified p53-associated factors, we have identified herpesvirus-associated ubiquitin-specific protease (HAUSP) as a novel p53-interacting protein. HAUSP strongly stabilizes p53 even in the presence of excess Mdm2, and also induces p53-dependent cell growth repression and apoptosis. Significantly, HAUSP has an intrinsic enzymatic activity that specifically deubiquitinates p53 both in vitro and in vivo. In contrast, expression of a catalytically inactive point mutant of HAUSP in cells increases the levels of p53 ubiquitination and destabilizes p53. These findings reveal an important mechanism by which p53 can be stabilized by direct deubiquitination and also imply that HAUSP might function as a tumour suppressor in vivo through the stabilization of p53. [ABSTRACT FROM AUTHOR]

Examines the role of ribosomal protein in translation elongation in Escherichia coli mutants. Translation accuracy; Elongation rate; Translation processivity.

In ribosomal protein S12 mutant or L24 mutant the expression of λN gene was depressed at translational level. To study its mechanism the λN gene region of λN - lacZ gene fusion was trimmed from its 5′ end to 3′ end with DNA exonuclease III (DNA cxoIII) in order to alter the TIR (translational initiation region) and the ding region of λN gene. After DNA sequencing 23 species of different λN-lacZ fused genes were obtained. The β-galactosidase activities of these deletants in ribosomal protein mutant were compared with that in wild type strain. The result indicated that (i) S12 mutant could affect 305 subunit’s binding to the TIR of λN gene messenger and cause the difficulty in forming 30s initiation complex and then decrease the efficiency of translational initiation; (ii) in S12 mutant the coding region of λN gene alw affected the expression λN gene; (iii) in L24 mutant the inhibition of λN gene expression was not related to translational initiation and the 5′ end of the coding region of λN gene, but related to the 3′ end of λN gene. [ABSTRACT FROM AUTHOR]