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Background: Cervical cancer is a prevalent malignancy of the female reproductive system. Cervical intraepithelial neoplasia (CIN) is a precursor lesion for CC. Various studies have examined circulating microRNAs (miRNAs) as potential early diagnostic markers for CC and CIN. However, the findings have been inconclusive. Therefore, it is necessary to evaluate the diagnostic accuracy and identify potential sources of variability among these studies. Methods: The PubMed, Cochrane Library, Embase, and Web of Science databases were searched to identify relevant literature. Then, Stata 14.0 was utilized to calculate summary estimates for diagnostic parameters, including sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the summary receiver operating characteristic (ROC). To scrutinize the heterogeneity, the Cochran-Q test and I2 statistic were utilized. As significant heterogeneity was observed, the random effects model was chosen. To explore potential sources of the heterogeneity, subgroup and regression analyses were conducted. Results: We analysed 12 articles reporting on 24 studies involving 1817 patients and 1731 healthy controls. The pooled sensitivity was 0.77 (95% CI 0.73–0.81), the specificity was 0.81 (95% CI 0.73–0.86), the PLR was 3.99 (95% CI 2.81–5.65), the NLR was 0.28 (95% CI 0.23–0.35), the DOR was 14.18 (95% CI 8.47–23.73), and the area under the curve (AUC) was 0.85 (95% CI 0.81–0.87). Subgroup analysis revealed that multiple miRNAs can improve diagnostic performance; the pooled sensitivity of multiple miRNAs was 0.78 (95% CI 0.68–0.86), the specificity was 0.85 (95% CI 0.78–0.90), and the AUC was 0.89 (95% CI 0.86–0.91). Conclusion: This study suggested that circulating microRNAs may be biomarkers for early CC diagnosis. [ABSTRACT FROM AUTHOR]

Heavy precipitation events can exert greater impact than general precipitation on the economy, ecology, and people's livelihoods. Based on CN05.1 daily precipitation data and the NCEP/NCAR global daily reanalysis dataset, this study analyzes the characteristics of clustered heavy precipitation (CHP) events during summer in Northeast China (NEC) during 1961–2020, with consideration of associated atmospheric circulations and moisture transport. Results indicate that CHP events occurred mainly during midsummer, especially in July. Both the frequency and the intensity of CHP events decrease after the mid-1970s, increase after the early 1980s, and then diminish again after the 2000s. The CHP events occur in association with an anomalous lower-tropospheric cyclone centered over NEC, northward and westward shifts of the western North Pacific subtropical high in the middle troposphere, and northward shift of an intensified westerly jet in the upper troposphere, in conjunction with strengthened local convective motion. Additionally, the net moisture budget begins to increase 2 days before the occurrence of CHP and peaks 6 h earlier than the CHP. Further results indicate that net moisture influx across the southern boundary of NEC made a dominant contribution to the net moisture budget. The results of this study have importance regarding the prediction of CHP events over NEC. [ABSTRACT FROM AUTHOR]

Existing evidence has explained the critical role of endogenous peptides in cancers, however, the peptidomic profile and function involved in endometrial carcinoma (EC) is still unknown. Here we aim to characterize the differentially expressed peptides with the potential involved in EC tumorigenesis and progression. Liquid chromatography-tandem mass spectrometry analysis (LC-MS/MS) was employed to compare the differentiated peptides using EC samples, followed with bioinformatics analysis including GO, KEGG enrichment analysis and functional studies, i.e., Cell counting kit 8 assay, transwell and wound healing assay to investigate the biological functions of these peptides. The related mRNA and protein levels of cell migration and invasion were selectively assessed by RT-PCR and Western blot analysis. A total of 383 peptides derived from 153 precursor proteins were identified, among which 12 were differentially expressed and corresponded to 8 precursor proteins. Bioinformatics analysis indicated they could play an important role in EC, in particular peptide IQGITKPAIR derived from the precursor protein Histone H4 can significantly inhibit the proliferation, migration, and invasion of EC cells through regulating the markers associated with Wnt/β-catenin/EMT signaling strategy. Our study provided better understanding of EC tumorigenesis and progression from the perspective of peptidomic analysis and may offer potential therapeutic candidates targeting EC. [ABSTRACT FROM AUTHOR]

The sentence-level sentiment classification is a classic topic of natural language processing, which aims to decide the sentiment tendency toward a sentence. However, previous studies ignore the significant role of words with sentimental tendencies in sentiment classification. In this paper, a sentiment information convolutional neural network (SI-CNN) model is proposed to break through this bottleneck problem. SI-CNN model contains three channels, where the first extracts original features from sentences, the second focuses on the words with sentiment tendencies, and the third is responsible for the categories and locations of the words with sentimental tendencies. We evaluate our model on three large-scale datasets. Experimental results show that the proposed SI-CNN outperforms other state-of-the-art deep neural networks and the introduction of sentiment information can improve the accuracy of sentiment classification. We also implement a series of exploratory experiments to prove the rationality of SI-CNN. [ABSTRACT FROM AUTHOR]

Material-based tactics have attracted extensive attention in driving the functional evolution of organisms. In aiming to design steerable bioartificial organisms to scavenge pathogenic waterborne viruses, we engineer Paramecium caudatum (Para), single-celled microorganisms, with a semiartificial and specific virus-scavenging organelle (VSO). Fe3O4 magnetic nanoparticles modified with a virus-capture antibody (MNPs@Ab) are integrated into the vacuoles of Para during feeding to produce VSOs, which persist inside Para without impairing their swimming ability. Compared with natural Para, which has no capture specificity and shows inefficient inactivation, the VSO-engineered Para (E-Para) specifically gathers waterborne viruses and confines them inside the VSOs, where the captured viruses are completely deactivated because the peroxidase-like nano-Fe3O4 produces virus-killing hydroxyl radicals (•OH) within acidic environment of VSO. After treatment, magnetized E-Para is readily recycled and reused, avoiding further contamination. Materials-based artificial organelles convert natural Para into a living virus scavenger, facilitating waterborne virus clearance without extra energy consumption. The material-based evolution of organisms has attracted broad interdisciplinary interest, however, the fabrication of material-integrated organelles remains inadequately exploited. Here the authors engineer a bioartificial organism by integrating a semiartificial and specific virus-scavenging organelle to scavenge pathogenic waterborne viruses. [ABSTRACT FROM AUTHOR]

Compared with individual extreme events, compound events have more severe impacts on humans and the natural environment. This study explores the change in severity of compound extreme high temperature and drought/rain events (CHTDE/CHTRE) and associated influencing factors. The CHTDE and CHTRE intensified in most areas of China in summer (June–July August) during 1961–2014. Under global warming, the increased water-holding capacity of the atmosphere and the decreased relative humidity led to an increase in the severity of CHTDE. The severity of CHTRE is increased because of enhanced transient water vapor convergence and convective motion. Anthropogenic climate change, especially greenhouse gas forcing, which contributes 90% to the linear change in the severity of CHTDE and CHTRE, is identified as the dominant factor affecting the severity of CHTDE in China. In addition, the historical natural forcing (hist-NAT) may be related to the interannual-to-decadal variability in the severity of CHTDE/CHTRE. [ABSTRACT FROM AUTHOR]

Aspect-based sentiment analysis has been a popular topic in natural language processing in recent years that aims to determine the sentiment polarity of a specific aspect in one context. However, most existing models only focus on feature extraction and ignore the significant role of words with sentiment tendency (e.g. good, terrible), which results in low classification accuracy. In this paper, a sentiment knowledge-based bidirectional encoder representation from transformers (SK-BERT) is proposed to overcome this shortcoming. To introduce sentiment knowledge, SK-BERT first integrates sentiment knowledge words into independent sequences and then encodes the sequence and context into static and dynamic vectors with the BERT pretrained models, respectively. All vectors are sent to the sentiment centre to generate different dimension representations for classification. We evaluate our model on three widely used datasets. Experimental results show that the proposed SK-BERT model outperforms other state-of-the-art models. Furthermore, visualization experiments are implemented to prove the rationality of SK-BERT. [ABSTRACT FROM AUTHOR]

As one of the most populated agricultural habitats in the world, Southeast Asia has been highly exposed to extremes of weather and climate, posing great importance to figure out the trend and variability characteristics of extremes over there. The annual extreme precipitation and temperature over Southeast Asia during 1981–2017 are analyzed in this study using datasets based on daily observations derived from thousands of meteorological stations. Results show that the wet extremes decrease over the areas surrounding the South China Sea and increase over the south of the Philippines and Indonesia with the most significant trends detected over the east of Indochina and New Guinea. Extreme high temperatures decrease significantly over the middle of New Guinea and increase over Indochina, Sumatra, Java, and Kalimantan. Moreover, empirical orthogonal function (EOF) analyses show that the first principal components for most precipitation extremes are characterized by significant decadal changes relevant to the Atlantic Multidecadal Oscillation and Pacific Decadal Oscillation, and the second principal components exhibit significant interannual variability associated with oceanic systems such as El Niño–Southern Oscillation (ENSO). As for temperature extremes, the leading EOF modes show non-significant trends or decadal variations, but significant interannual variations related to ENSO and the Indian Ocean Dipole are detected. [ABSTRACT FROM AUTHOR]

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The blood flow restoration of ischemic tissues causes myocardial injury. Dexmedetomidine (Dex) protects multi-organs against ischemia/reperfusion (I/R) injury. This study investigated the protective mechanism of Dex post-treatment in myocardial I/R injury. The rat model of myocardial I/R was established. The effects of Dex post-treatment on cardiac function and autophagy flow were observed. Dex attenuated myocardial I/R injury and reduced I/R-induced autophagy in rats. Dex weakened the interactions between Beclin1 and Vps34 and Beclin1 and Atg14L, thus downregulating Vps34 kinase activity. In vitro, the cardiomyocytes subjected to oxygen glucose deprivation/reoxygenation were treated with Dex and PI3K inhibitor LY294002. LY294002 attenuated the myocardial protective effect of DEX, indicating that Dex protected against cardiac I/R by activating the PI3K/Akt pathway. In conclusion, Dex upregulated the phosphorylation of Beclin1 at S295 site by activating the PI3K/Akt pathway and reduced the interactions of Atg14L-Beclin1-Vps34 complex, thus inhibiting autophagy and protecting against myocardial I/R injury. [ABSTRACT FROM AUTHOR]

A single-camera synthetic Schlieren method is introduced to measure the height of a dynamic free liquid surface in a container with a flat bottom. Markers placed on the bottom, seen through the free surface, are virtually displaced due to light refraction at the surface. According to Snell's law, the marker displacements depend on the refractive indices of the transparent liquid and the air, and on the surface height and its spatial gradients. We solve the resulting governing nonlinear equation with the Newton–Raphson method to obtain the surface height. Our method does not require a reference surface height, which allows the measurement of surfaces topography in situations where the liquid depth is unknown. We demonstrate the accuracy of the method by performing experiments of surface ripples and dam-break flows and discuss the measurement uncertainty, errors and limitations. [ABSTRACT FROM AUTHOR]

Ruxolitinib (RUX), a JAK1/2-inhibitor, is effective for myeloproliferative neoplasm (MPN) with both JAK2V617 F and calreticulin (CALR) mutations. However, many MPN patients develop resistance to RUX. Although mechanisms of RUX-resistance in cells with JAK2V617 F have already been characterized, those in cells with CALR mutations remain to be elucidated. In this study, we established RUX-resistant human cell lines with CALR mutations and characterized mechanisms of RUX-resistance. Here, we found that RUX-resistant cells had high levels of MPL transcripts, overexpression of both MPL and JAK2, and increased phosphorylation of JAK2 and STAT5. We also found that mature MPL proteins were more stable in RUX-resistant cells. Knockdown of MPL in RUX-resistant cells by shRNAs decreased JAK/STAT signaling. Immunoprecipitation assays showed that binding of mutant CALR to MPL was increased in RUX-resistant cells. Reduction of mutated CALR decreased proliferation of the resistant cells. When resistant cells were cultured in the absence of RUX, the RUX-resistance was reversed, with reduction of the mutant-CALR/MPL complex. In conclusion, MPL overexpression induces higher levels of a mutant-CALR/MPL complex, which may cause RUX-resistance in cells with CALR mutations. This mechanism may be a new therapeutic target to overcome RUX-resistance. [ABSTRACT FROM AUTHOR]

Gut microbiota have a significant impact on host physiology and health, and host genetics and diet are considered as two important factors, but it is difficult to discriminate the influence of each single factor (host or diet) on gut microbiota under natural conditions. Moreover, current studies of avian microbiota mainly focus on domestic or captive birds, and it is still uncertain how host and diet take part in changing avian gut microbiota composition, diversity, and function in the wild. Here, high-throughput sequencing of 16S rRNA was used to identify the gut microbiota communities for sympatric wintering Great Bustards and Common Cranes at different diets. The results showed that 8.87% operational taxonomic units (OTUs) were shared among all sampling birds; in contrast, 39.43% of Kyoto Encyclopedia of Genes and Genomes (KEGG) functional pathways were common among all individuals, indicating the existence of gut microbiota conservatism both in microbiota structure and function. Microbiota abundance and diversity differed between Great Bustards and Common Cranes in a specific wintering site, and microbiota variation was detected for the same host species under two different sites, suggesting that the change of gut microbiota was induced by both host and diet. Furthermore, we found that changes of both microbial communities and functional pathways were larger between hosts than those between diets, which revealed that host might be the dominant factor determining microbiota characteristics and function, while diet further drove the divergence of gut microbiota. Gut microbiota functions appeared to be more conserved than bacterial community structure, indicating that different bacteria may function in a similar way, while microbiota OTU diversity might not be necessarily associated with functional diversity. With diet shifting, gut microbiota changed both in terms of microbial communities and functional pathways for the sympatric birds, which implies that avian habitats and their physiological microbiota would be influenced by different farmland management regimes. Key points: • Gut microbiota can be shaped by both diets and hosts in sympatric species. • Host was the dominant factor shaping the gut microbiota communities and functional pathways. • Gut microbiota were conservative both in structure and in function, but more conservative in function. [ABSTRACT FROM AUTHOR]

Plant- and/or microbe-based systems can provide a cost-effective, sustainable means to remove contaminants from soil. Microbe-assisted phytoremediation has potential utility for polycyclic aromatic hydrocarbons such as fluoranthene (Flu) removal from soils; however, the efficiency varies with the plant and microbes used. This study evaluated the Flu removal efficiency in a system with ryegrass (Lolium multiflorum), an IAA-producing Arthrobacter pascens strain (ZZ21), and/or a Flu-degrading Bacillus cereus strain (Z21). Strain ZZ21 significantly enhanced the growth of ryegrass. Ryegrass in combination with both strains (FIP) was the most effective method for Flu removal. By day 60, 74.9% of the Flu was depleted in the FIP treatment, compared with 21.1% in the control (CK), 63.7% with ryegrass alone (P), 69.0% for ryegrass with ZZ21 (IP), and 72.6% for ryegrass with Z21 (FP). FIP treatment promoted ryegrass growth, accelerated Flu accumulation in plants, and increased soil microbial counts. Microbial carbon utilization was significantly higher in soil in the FIP than with the CK treatment. Principal component analysis of the distribution of carbon substrate utilization showed that microbial functional profiles diverged among treatments, and this divergence became more profound at day 60 than day 30. Microbial inoculation significantly enhanced microbial utilization of phenols. Microbes in the FIP soil dominantly utilized amines/amides and phenols at day 30 but shifted to carbohydrates by day 60. Together, the combination of IAA-producing microbes and Flu-degrading microbes could promote plant growth, facilitate Flu degradation, and change soil microbial functional structure. [ABSTRACT FROM AUTHOR]

42025502 and 41875119)" and should have read "This work was jointly supported by Guangdong Major Project of Basic and Applied Basic Research (Grant No. 2020B0301030004) and the National Natural Science Foundation of China (Grant No. 41875119)" The original article has been corrected. The online version of the original article can be found at https://doi.org/10.1007/s00382-023-06944-y. [Extracted from the article]

Amphibians are experiencing worldwide declines due to increasing anthropogenetic disturbances. However, the genetic variability and hence adaptability are still unknown for most frogs. We integrated the mitochondrial (ND2 gene), nuclear (TYR gene) and major histocompatibility complex (MHC) loci, to clarify the demographic patterns and immune-gene diversity of the Lolokou Sucker Frog (Amolops loloensis). Demographic analysis of the ND2 and TYR genes suggested that the Lolokou Sucker Frog experienced a population expansion within the last 10,000 years. High MHC diversity was detected, which has likely resulted from positive selection, indicating the current diversity bodes well for the species' adaptive potential to pathogenic challenges. These findings broaden our knowledge on the population history and evolution adaptation of the reclusive torrent frog, and conservation implications are provided. [ABSTRACT FROM AUTHOR]

Functional applications of cellulose have attracted large amount of attentions owing to its natural, environmentally friendly, light-weight characteristics. In this study, a cellulose-based conductive film (CCF) was prepared by sputtering aluminum doped zinc oxide (AZO, a cheap and non-toxic semiconductor) on a regenerated cellulose film from bamboo fibers. Through dissolution and regenerated process of cellulose fibers, the as-prepared cellulose film featured high transmittance of 97% and low roughness of 0.943 nm as well as 117 MPa strength, which can be supportive for manufacturing cellulose-based conductive devices. Based on the cellulose film which was as the transparent substate, we systematically investigated the effects of working parameters on the performance of AZO-based cellulose conductive film, followed by a phenomenon that the crystal structure and morphology of AZO particles play decisive role on the transmittance and conductivity of CCF. With the optimized working parameters, the CCF presented low conductive resistance of 365 Ω/□, high transmittance of 86% and high-quality crystalline structure. Besides, the thermal stability and mechanical strength of CCF were also investigated. The prepared CCF is beneficial for manufacturing the transparently electronic devices with environmental-friendly merit. [ABSTRACT FROM AUTHOR]

This study investigated the application of fungus Aspergillus niger and geological fluorapatite (FAp) to cadmium (Cd) immobilization in aqueous solution. The initial Cd concentrations were set at 100, 50, 25, and 10 mg L−1. The mineralogy of the products was investigated by using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and attenuated total reflection–infrared spectroscopy (ATR-IR). In both A. niger + FAp + Cd and A. niger + Cd treatments, A. niger secreted abundant oxalic acid, then dissolved the FAp, and reacted with Cd2+ cations to produce relatively insoluble Cd oxalate. Meanwhile, FAp can provide P source to improve microbial growth. The fungal tolerance to Cd2+ was identified at around 100 mg L−1. The final Cd concentrations of 13.7, 3.2, and 0.2 mg L−1 were recorded for A. niger + FAp + Cd treatments with initial Cd concentrations of 50, 25, and 10 mg L−1 respectively. Meanwhile, it was observed that the Cd concentration at 25 mg L−1 stimulated higher bioactivities of A. niger, which further enhanced Cd bioremediation. The immobilization efficiency (%) of the treatments at low to medium Cd concentrations was in the order: Asp + FAp > Asp > FAp, while FAp alone was most efficient at the high Cd concentration of 100 mg L−1. This research provides insights into the mechanisms of combining fungus and FAp as a composite to Cd contamination at various Cd levels. [ABSTRACT FROM AUTHOR]

Mini-quadrotor is difficult to control in the air due to its small size and light weight. This paper presents the flight and hover control system for a mini-quadrotor, including design and simulation of calculations and controllers. Firstly, the attitude and position of the mini-quadrotor are obtained by distributed multi-sensors. Since attitude calculation of aircraft needs a number of combined rotations and vectors transformed by rotation, quaternions are applied to express the attitude model. About error compensation of gyroscope and accelerometer, IMU_Updata algorithm of Mahony filter are applied and improved to realize data fusion [1]. In order to realize accurate hovering at certain position, UWB (UltraWideband) are applied to gain positional information of mini-quadrotor and correct the antenna delay caused sensor error by base station positioning. The discrete Kalman filter of original data is used to achieve the optimized estimation of the airborne position. Px4flow optical flow sensor is able to gets velocity information and avoid the noise problem, which is caused by differential of position data. Then, the mathematical model of a mini-quadrotor's flight and hover control system can be established. Herein, integral items are solved by the integral separation and integral limiting to mitigate the serious overshoot and oscillation of the system caused by the cascade PID. Finally, the simulation of the attitude controller and position controller are applied with the MATLAB Simulink library. The simulation result shows that the designed attitude controller and position controller can enable the mini-quadrotor to fly smoothly, move in all directions and hover. [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyls (PCBs) are a class of man-made organic compounds ubiquitously present in the biosphere. In this study, we evaluated the toxic effects of different concentrations of PCBs in two natural soils (i.e. red soil and fluvo-aquic soil) on the earthworm Eisenia fetida. The parameters investigated included anti-oxidative response, genotoxic potential, weight variation and biochemical responses of the earthworm exposed to two different types of soils spiked with PCBs after 7 or 14 days of exposure. Earthworms had significantly lower weights in both soils after PCB exposure. PCBs significantly increased catalase (CAT), superoxide dismutase (SOD), and guaiacol peroxidase (POD) activity in earthworms exposed to either soil type for 7 or 14 days and decreased the malondialdehyde (MDA) content in earthworms exposed to red soil for 14 days. Of the enzymes examined, SOD activity was the most sensitive to PCB stress. In addition, PCB exposure triggered dose-dependent coelomocyte DNA damage, even at the lowest concentration tested. This response was relatively stable between different soils. Three-way analysis of variance (ANOVA) showed that the weight variation, anti-oxidant enzyme activities, and MDA contents were significantly correlated with exposure concentration or exposure duration ( P < 0.01). Furthermore, weight variation, CAT activity, and SOD activity were significantly affected by soil type ( P < 0.01). Therefore, the soil type and exposure time influence the toxic effects of PCBs, and these factors should be considered when selecting responsive biomarkers. [ABSTRACT FROM AUTHOR]

Insecticidal crystal (Cry) proteins produced by transgenic Bacillus thuringiensis (Bt) rice that enter the soil via root exudation and plant residues may be harmful to non-target soil organisms. We conducted a 3-year field investigation to determine if soil nematode abundance and diversity were affected by exposure to two transgenic Bt rice cultivars, compared to their non-transgenic near isolines. Near isolines were Kemingdao (KMD-Bt) expressing the single Cry1Ab gene and its non-Bt near isoline Xiushui-11 (XSD), as well as Huahui-1 (HH-Bt) expressing the fused Cry1Ab/Cry1Ac gene and its non-Bt near isoline Minghui-63 (MH). Nematode variables including community composition, abundance, trophic groups, and most of the common genera differed significantly between the rice cultivars. However, these nematode variables were similar under transgenic Bt rice and its non-Bt near isoline, although higher Shannon's index value and Pielou's index value were found in soils planted with Bt rice than the non-Bt near isoline. During this 3-year field study, gene modification (single Cry1Ab gene and fused Cry1Ab/Cry1Ac gene) supports a more uniform distribution of nematode species but had no effect on soil nematode abundance and community composition. We conclude that continuous cultivation of KMD-Bt and HH-Bt rice varieties for 3 years is not detrimental to soil nematode communities under field conditions. [ABSTRACT FROM AUTHOR]

Ion chromatography-ultra violet-hydride generation-Atomic Florescence Spectrometry was applied to detect 5 arsenic species in seafoods. The arsenic species studied include arsenobetaine (AsB), arsenite (As(III)), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), and arsenate (As(V)), which were extracted from samples using 2% formic acid. Gradient elution using 33 mmol L CHCOONH and 15 mmol L NaCO with 10 mL CHCHOH at pH 8.4 allowed the chromatographic separation of all the species on a Hamilton PRP-X100 anion-exchange column in less than 8 min. In this study, an ultrasound extraction method was used to extract arsenic species from seafood. The extraction efficiency was good and the recoveries from spiked samples were in the range of 72.6%-109%; the precision between sample replicates was higher than 3.6% for all determinations. The detection limits were 3.543 μg L for AsB, 0.426 μg L for As(III), 0.216 μg L for DMA, 0.211 μg L for MMA, and 0.709 μg L for As(V), and the linear coefficients were greater than 0.999. We also developed an application of this method for the determination of arsenic species in bonito, Euphausia superba, and Enteromorpha with satisfactory results. Therefore, it was confirmed that this method was appropriate for the detection of arsenic species in seafood. [ABSTRACT FROM AUTHOR]

In this study, we aimed to confirm that indole-3-acetic acid promotes plant uptake of phenanthrene (PHE), stimulates the activity of soil enzymes or microflora, and thereby accelerates the dissipation of PHE in soil. Four treatments were evaluated: PHE-contaminated soil planted with (1) ryegrass (T0), (2) ryegrass and supplemented with 1 mg kg indole-3-acetic acid (IAA) (T1), (3) ryegrass and supplemented with 5 mg kg IAA (T5), and (4) ryegrass and supplemented with 10 mg kg IAA (T10). After 30 days, PHE concentrations were lower for all treatments and the removal rate was 70.19, 89.17, 91.26, and 97.07 % for T0, T1, T5, and T10, respectively. PHE was only detected in the roots and not in the shoots. IAA facilitated the accumulation of PHE in the roots, and plants subjected to the T10 treatment had the highest levels. Exogenous IAA stimulated soil peroxidase activity in a dose-dependent manner, whereas soil polyphenoloxidase activity was not significantly increased, except in T10. Soil microbial biomass also increased in response to IAA treatment, particularly in T10. Furthermore, phospholipid fatty acid analysis showed that IAA treatment increased microbial biomass and alleviated environmental stress. Gram-positive bacteria are largely responsible for polycyclic aromatic hydrocarbon degradation, and we found that the ratio of gram-positive to gram-negative bacteria in the soil significantly increased as the IAA concentrations increased ( P < 0.05). Correlation analysis indicated that the increase in soil microbial biomass, enzyme activity, and plant uptake of PHE promotes removal of PHE from the soil. [ABSTRACT FROM AUTHOR]

Purpose: Remediation of polybrominated diphenyl ethers (PBDEs)/heavy metals/antibiotics mixed contaminated soil with high abundance of antibiotic resistance genes (ARGs) has being greatly challenging. Materials and methods: An elevated soil washing procedure was developed to investigate the potential of applying DNA solution to extract PBDEs, Cu, Pb, tetracycline, and sulfadiazine from a high abundance of ARG-affected soil, followed by microbial augmentation to restore the microbiological functioning of washed soil. Results and discussion: Two successive washings with 15 g L DNA solution plus ultrasonication (25 kHz for 15 min) were optimal for extracting 80.6 % BDE28, 85.2 % BDE47, 64.7 % Cu, 60.3 % Pb, 100 % tetracycline, and 100 % sulfadiazine. Simultaneously, the ARG abundance decreased to the level of 10-10 (ARGs copies/16S copies). Moreover, combined treatment with PBDE-degrading bacteria inoculation and nutrient application for 3 months to the second washed soil resulted in the further degradation of residual BDE28 and BDE47. Furthermore, the bacterial community composition was restored and the transfer risk of residual pollutants was limited, as indicated by high-throughput sequencing technology analysis and heavy metals stability model evaluation. Conclusions: The combined cleanup technology is an environmentally friendly and effective technology to remediate mixed contaminated soils. [ABSTRACT FROM AUTHOR]

An agar-degrading bacterium, strain LGH, was isolated and identified as Cohnella sp. This strain had a capability of utilizing agar as a sole carbon source for growth and showed a strong agarolytic activity. A novel endo-type β-agarase gene agaW, encoding a primary translation product of 891 amino acids, including a 26 amino acid signal peptide, was cloned and identified from a genomic library of strain LGH. The AgaW belonged to the glycoside hydrolase (GH) GH50 family, with less than 39 % amino acid sequence similarity with any known protein, and hydrolyzed agarose into neoagarotetraose as the major end product and neoagarobiose as the minor end product through other neoagarooligosaccharide intermediates, such as neoagarohexaose. [ABSTRACT FROM AUTHOR]

In agricultural ecosystems, most crop cultivars are bred for pest resistance with the aim of resisting aboveground herbivores, but it is unclear if this resistance also affects abundance, composition, and activity of underground pests and content of soil labile pools. A fully factorial greenhouse experiment was carried out, using four rice cultivars with distinct resistance to shoot herbivore brown planthopper, Nilaparvata lugens, with and without rice root nematodes, Hirschmanniella spp., to test two hypotheses: (1) rice cultivars resistant to brown planthopper are more susceptible to rice root nematodes and (2) rice root nematodes of resistant cultivars cause greater modification of labile pools of rhizosphere soil than those of susceptible cultivars by inducing more leakage of plant metabolites. Nematode abundance, soluble sugar and soluble amino acid contents of plant, and microbial biomass C and N, dissolved organic C and N, and soluble sugar and amino acid contents of rhizosphere soil were analyzed. The abundance of rice root nematodes substantially increased under all rice cultivars following root nematode inoculation. Rice cultivar resistance to brown planthopper did not affect the numbers of rice root nematodes but decreased negative effects of nematodes on root growth, shoot soluble sugar and amino acid contents, and labile pools of rhizosphere soil, probably implying that integrated complex mechanisms other than only resource allocation were involved in rice resistance to aboveground and belowground herbivores. Our study will contribute to a better understanding of aboveground-belowground interactions and to the development of integrated pest managements by considering belowground ecosystem responses in crop systems. [ABSTRACT FROM AUTHOR]

An innovative ex situ soil washing technology was developed to remediate polybrominated diphenyl ethers (PBDEs) and heavy metals in an electronic waste site. Elevated temperature (50 °C) in combination with ultrasonication (40 kHz, 20 min) at 5.0 mL L sunflower oil and 2.5 g L carboxymethyl chitosan were found to be effective in extracting mixed pollutants from soil. After two successive washing cycles, the removal efficiency rates for total PBDEs, BDE28, BDE47, BDE209, Pb, and Cd were approximately 94.1, 93.4, 94.3, 99.1, 89.3, and 92.7 %, respectively. Treating the second washed soil with PBDE-degrading bacteria ( Rhodococcus sp. strain RHA1) inoculation and nutrient addition for 3 months led to maximum biodegradation rates of 37.3, 52.6, 23.9, and 1.3 % of the remaining total PBDEs, BDE28, BDE47, BDE209, respectively. After the combined treatment, the microbiological functions of washed soil was partially restored, as indicated by a significant increase in the counts, biomass C, N, and functioning diversity of soil microorganisms ( p < 0.05), and the residual PBDEs and heavy metals mainly existed as very slow desorbing fractions and residual fractions, as evaluated by Tenax extraction combined with a first-three-compartment model and sequential extraction with metal stability indices ( I and U). Additionally, the secondary environmental risk of mixed contaminants in the remediated soil was limited. Therefore, the proposed combined cleanup strategy is an environment-friendly technology that is important for risk assessment and management in mixed-contaminated sites. [ABSTRACT FROM AUTHOR]

Purpose: Problems associated with Organochlorine pesticide (OCP)-contaminated soils have received wide attention. To understand the anaerobic biodegradation process constraints, innovative mathematical analysis methods are effective. Materials and methods: Response surface methodology (RSM) and Tenax TA extraction method combined with the first-three-compartment model were employed to systematically investigate the role of nitrate concentration and bioaccessibility enhancer (methyl-β-cyclodextrin, MCD) in the anaerobic biodegradation of OCPs in contaminated soil. Results and discussion: The sole addition of either KNO or MCD could facilitate the anaerobic biodegradation of OCPs. The highest biodegradation for total OCPs, hexachlorocyclohexanes, endosulfans, and chlordanes were 71.6, 82.1, 68.3, and 55.6 %, respectively, when 20 mM KNO and 3.0 % ( w/ w) MCD were applied simultaneously. As predicted by RSM, the theoretical maximum biodegradation for total OCPs ranged from 60 to 80 % when 20 to 25 mM KNO and >2.5 % ( w/ w) MCD were applied simultaneously. Tenax TA extraction method demonstrated the enhancement of OCP bioaccessibility caused by MCD addition. Changes in the soil microbial activities also suggested the positive effects of adding suitable amounts of KNO as a cosubstrate to facilitate the anaerobic biodegradation of OCPs. Conclusions: The amount of KNO and MCD are crucial in influencing OCP biodegradation. RSM was demonstrated to be a powerful tool to estimate and predicting the optimal OCP biodegradation under KNO and MCD application simultaneously. [ABSTRACT FROM AUTHOR]

The present study was conducted to investigate the anaerobic biodegradation potential of biostimulation by nitrate (KNO) and methyl-β-cyclodextrin (MCD) addition on an aged organochlorine pesticide (OCP)-contaminated paddy soil. After 180 days of incubation, total OCP biodegradation was highest in soil receiving the addition of nitrate and MCD simultaneously and then followed by nitrate addition, MCD addition, and control. The highest biodegradation of chlordanes, hexachlorocyclohexanes, endosulfans, and total OCPs was 74.3, 63.5, 51.2, and 65.1 %, respectively. Meanwhile, MCD addition significantly increased OCP bioaccessibility ( p < 0.05) evaluated by Tenax TA extraction and a three-compartment model method. Moreover, the addition of nitrate and MCD also obtained the highest values of soil microbial activities, including soil microbial biomass carbon and nitrogen, ATP production, denitrifying bacteria count, and nitrate reductase activity. Such similar trend between OCP biodegradation and soil-denitrifying activities suggests a close relationship between OCP biodegradation and N cycling and the indirect/direct involvement of soil microorganisms, especially denitrifying microorganisms in the anaerobic biodegradation of OCPs. [ABSTRACT FROM AUTHOR]

Organophosphorus compounds (OP) are stable P source in nature, and can increase eutrophication risk in waterbodies. Lecithin was the most difficult OP to be broken down. In this study, two typical phosphate-solubilizing microorganisms, Aspergillus niger and Acinetobacter sp., were applied to evaluate their ability to decompose both inorganic phosphates and lecithin. A. niger and Acinetobacter sp. could solubilize calcium phosphates by secreting various organic acids, e.g., oxalic and formic acids. The fungus, A. niger, shows significantly higher ability of solubilizing these inorganic phosphates than Acinetobacter sp., primarily due to its secretion of abundant oxalic acid. However, the bacterium, Acinetobacter sp., could secrete more acid phosphatase than A. niger for lecithin decomposition, i.e., 9300 vs. 8500 μmol L−1 h−1. Moreover, after addition of CaCl2, the released P from lecithin was transformed to stable chlorapatite in the medium. To the contrast, Ca cations inclined to form calcium oxalate (rather than stable phosphate mineral) after the incubation of A. niger, as it induced relatively acidic environment after breaking down lecithin. Therefore, this work sheds light on the bright future of applying bacteria and Ca cations in OP pollutant management. [ABSTRACT FROM AUTHOR]

This paper has been retracted. [ABSTRACT FROM AUTHOR]

Bacterial persisters are phenotypic variants that tolerate exposure to lethal antibiotics. These dormant cells are responsible for chronic and recurrent infections. Multiple mechanisms have been linked to persister formation. Here, we report that a complex, consisting of an extracellular poly(dC) and its membrane-associated binding protein RmlB, appears to be associated with persistence of the opportunistic pathogen Pseudomonas aeruginosa. Environmental stimuli triggers a switch in the complex physiological state (from poly(dC)/RmlB to P-poly(dC)/RmlB or RmlB). In response to the switch, bacteria decrease proton motive force and intracellular ATP levels, forming dormant cells. This alteration in complex status is linked to a (p)ppGpp-controlled signaling pathway that includes inorganic polyphosphate, Lon protease, exonuclease VII (XseA/XseB), and the type III secretion system. The persistence might be also an adaptive response to the lethal action of the dTDP-L-rhamnose pathway shutdown, which occurs due to switching of poly(dC)/RmlB. The mechanisms underlying bacterial persisters formation remain poorly understood. Here, Chen et al. identify a complex formed by extracellular poly(dC) and the binding protein RmlB that controls Pseudomonas aeruginosa persister formation in response to environmental stimuli. [ABSTRACT FROM AUTHOR]