A novel copper-based MOFs adsorbent (Cu-BTC-Th) was prepared using an one-step method by introducing a new organic ligand of 4-thioureidobenzoicacid (Th) with active groups for selectively adsorbing ...Pb(II) from aqueous solutions. The chemical composition and structure of the prepared MOFs materials were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS ), Brunner−Emmet−Teller (BET) analysis, and zeta potential measurements. The adsorption capability of the prepared Cu-MOFs was significantly enhanced by introducing the new organic ligand of Th in the materials. The maximum adsorption capacity of the Cu-BTC-Th for Pb(II) attains 732.86 mg/g under the optimal conditions. In addition, the adsorption kinetics and adsorption isotherm analysis showed that the adsorption process followed the pseudo-second-order kinetic model and Langmuir adsorption model, indicating that the adsorption of Pb(II) by Cu-BTC-Th was a monolayer chemisorption. The adsorption mechanism of Cu-BTC-Th for Pb(II) was discussed and revealed. On one hand, the adsorption of Pb(II) is mainly through ion exchange with the Cu(II). On the other hand, the −NH2 and −C=S functional groups introduced in the Cu-BTC-Th materials have stronger coordination ability with the Pb(II) ions to enhance the adsorption capability.
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GhMYB4 acts as a negative regulator in lignin biosynthesis, which results in alteration of cell wall integrity and activation of cotton defense response.
Verticillium wilt of cotton (
...Gossypium hirsutum
) caused by the soil-borne fungus
Verticillium dahliae
(
V. dahliae
) represents one of the most important constraints of cotton production worldwide. Mining of the genes involved in disease resistance and illuminating the molecular mechanisms that underlie this resistance is of great importance in cotton breeding programs. Defense-induced lignification in plants is necessary for innate immunity, and there are reports of a correlation between increased lignification and disease resistance. In this study, we present an example in cotton whereby plants with reduced lignin content also exhibit enhanced disease resistance. We identified a negative regulator of lignin synthesis, in cotton encoded in GhMYB4. Overexpression of
GhMYB4
in cotton and
Arabidopsis
enhanced resistance to
V. dahliae
with reduced lignin deposition. Moreover, GhMYB4 could bind the promoters of several genes involved in lignin synthesis, such as
GhC4H-1
,
GhC4H-2
,
Gh4CL-4,
and
GhCAD-3
, and impair their expression. The reduction of lignin content in
GhMYB4
-overexpressing cotton led to alterations of cell wall integrity (CWI) and released more oligogalacturonides (OGs) which may act as damage-associated molecular patterns (DAMPs) to stimulate plant defense responses. In support of this hypothesis, exogenous application with polygalacturonic acid (PGA) in cotton activated biosynthesis of jasmonic acid (JA) and JA-mediated defense against
V. dahliae
, similar to that described for cotton plants overexpressing
GhMYB4
. This study provides a new candidate gene for cotton disease-resistant breeding and an increased understanding of the relationship between lignin synthesis, OG release, and plant immunity.
Directly discharging low-concentration rare-earth wastewater not only wastes rare-earth resources but also pollutes the environment. In this study, the biosorption behavior of
Serratia marcescens
for ...Eu(III) was studied with emphasis on the optimization of adsorption conditions, adsorption kinetics, and adsorption isotherm. It was shown that the maximum adsorption capacity of
Serratia marcescens
reached 115.36 mg·g
−1
under an optimal condition, indicating the good adsorption capability of
Serratia marcescens
for Eu(III). The adsorption kinetics and adsorption isotherm analysis showed that the adsorption process conforms to the pseudo-second-order kinetic model and Langmuir adsorption isotherm, indicating that the adsorption of Eu(III) by
Serratia marcescens
is a monolayer chemical adsorption process. In addition, the adsorption mechanism was investigated by using characterizations of zeta potential, scanning electron microscope–energy dispersive spectrometer (SEM-EDS), Fourier transform infrared (FT-IR), and X-ray photoelectron spectroscopy (XPS) analyses. It was revealed that the adsorption of Eu(III) by
S. marcescens
is a combination of electrostatic attraction, ions exchange and coordination. These findings indicate that S. marcescens can be used as a potential biosorbent to recover rare earth elements from rare earth wastewater.
In this study, attapulgite (AT) and graphene oxide (GO) nanosheets were grafted together via a silane coupling agent to synthesize attapulgite–graphene oxide (AT–GO) composites and apply them to ...remove the emulsified oil from the oily wastewater. The structure and morphology of the AT–GO composites were characterized by Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy, zeta potential measurements, and transmission electron microscopy. The amphiphilicity of the AT–GO composites was evaluated by visual observation of their distribution in the oil–water mixture. The results showed that the AT–GO composites have been successively prepared and have good amphiphilic and interfacial activity. The effects of the pH, demulsifier dosage, temperature, and the mass ratio of AT and GO (R A/G) in the composites on the demulsification performance of AT–GO were studied. It was found that the demulsification process could be completed efficiently and quickly at room temperature. Under optimal demulsification conditions, the demulsification efficiency is above 95%. The demulsification mechanism was studied and discussed. It is believed that the interaction behavior between the AT–GO material and the emulsified molecules of asphaltenes is a key for the demulsification. Once the nanoparticles are combined with the emulsified molecules, the external stirring, vibration, and other mechanical actions provide them enough kinetic energy to destroy the protective film at the oil/water interface and then promote the merging of dispersed oil droplets to realize the oil–water separation.
Verticillium wilt is a severe disease of cotton crops in Xinjiang and affecting yields and quality, due to the continuous cotton cropping in the past decades. The relationship between continuous ...cropping and the changes induced on soil microbiome remains unclear to date. In this study, the culture types of 15 isolates from Bole (5F), Kuitun (7F), and Shihezi (8F) of north Xinjiang were sclerotium type. Only isolates from field 5F belonged to nondefoliating pathotype, the others belonged to defoliating pathotype. The isolates showed pathogenicity differentiation in cotton. Fungal and bacterial communities in soils had some difference in alpha-diversity, relative abundance, structure and taxonomic composition, but microbial groups showed similarity in the same habitat, despite different sampling sites. The fungal phyla Ascomycota, and the bacterial phyla Proteobacteria, Actinobacteria, Chloroflexi, Acidobacteria and Gemmatimonadetes were strongly enriched. Verticillium abundance was significantly and positively correlated with AN, but negatively correlated with soil OM, AK and pH. Moreover, Verticillium was correlated in abundances with 5 fungal and 6 bacterial genera. Overall, we demonstrate that soil microbiome communities have similar responses to long-term continuous cotton cropping, providing new insights into the effects of continuous cotton cropping on soil microbial communities.
•We identified different boiling morphologies near the Leidenfrost point.•Boiling includes reflection and explosive rebound, explosive detachment.•An empirical correlation for predicting the maximum ...spread factor was provided.•A model was proposed to describe the dimensionless time scale in drop rebound.•Preliminary analysis was undertaken for the drop detaching time from the wall.
With aid of high-speed imaging, boiling phenomena near the Leidenfrost point from a single liquid drop impact on a heated solid wall were identified, including reflection rebound, explosive rebound and explosive detachment. Wall temperature was ranging in 182–384°C, and water, butanol, ethanol and 5.21% NaCl solution were adopted as the fluids due to their different properties. Transitions in the three boiling phenomena were determined concerning effects of Weber number and wall temperature, respectively. For the process of reflection rebound, the maximum spread factor and resident time of the drop are independent of wall temperature. With an increment in Weber number, the maximum spread factor rises, while its effect on the resident time is minor. Empirical correlations were acquired to predict the maximum spread factor and its corresponding dimensionless time as well as the dimensionless resident time. Moreover, formation of the central liquid jet was observed using the NaCl solution drop, which was interpreted by bubble entrainment with violent nucleating. Finally, preliminary discussions regarding drop detaching time in the explosive detachment process were undertaken. Results revealed that the drop detaching time decreases with Weber number, and wall temperature also can affect it.
Graphene-based nanocomposites are emerging as a new class of materials that hold promise for many applications. In this paper, we present a general approach for the preparation of sandwich-like ...graphene/ZnO nanocomposites in ethylene glycol (EG) medium using graphene oxide as a precursor of graphene and zinc acetylacetonate as a single-source precursor of zinc oxide. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, ultraviolet–visible (UV–vis) spectroscopy and thermogravimetry analysis. It was shown that the as-formed ZnO nanoparticles with a diameter of about 5
nm were densely and uniformly deposited on both surfaces of the graphene sheets to form a sandwich-like composite structure and as a result, the restacking of the as-reduced graphene sheets was effectively prevented. The ZnO-coated graphene nanocomposites can be expected to effectively improve the photocatalysis and sensing properties of ZnO and would be promising for practical applications in future nanotechnology.
Cisplatin resistance is the main reason for uveal melanoma (UM) treatment failure. Thus, developing strategy that increasing cisplatin sensitivity is needed. In this study, we performed drug ...repositioning analysis with the Connectivity Map database using a panel of previously identified cisplatin sensitivity–associated genes and cisplatin resistance–associated genes as the signature and obtained the antiparasitic drug selamectin. We demonstrated that the selamectin and cisplatin combination showed a synergistic effect on inhibiting UM cell growth. Experiments in tumor-bearing nude mice further showed that selamectin and cisplatin have synergistic effects in reducing tumor growth. Previous studies have linked increased autophagy with tumor resistance to chemotherapy. We found that selamectin inhibited the expression of the autophagy-related gene ATG9B, thus reducing autophagy. The cisplatin resistance–associated genes PDGFRB, DUSP1, MAST1 and IL11 were significantly downregulated in UM cells treated with selamectin. In summary, our study shows that selamectin enhanced the sensitivity of UM to cisplatin, through the mechanism of inhibiting cisplatin resistance–associated gene expression and autophagy. These findings may provide a new strategy for the treatment of UM.
•Selamectin increases the cisplatin sensitivity of uveal melanoma both in vitro and in vivo.•Selamectin inhibits autophagy of uveal melanoma by decreasing ATG9B expression.•Selamectin downregulates cisplatin-resistant genes in uveal melanoma.
Osteosarcoma is the most common type of primary tumor of bone which mainly affects adolescents and young adults. Osteosarcoma causes large number of deaths because of its complex pathogenesis and ...resistance to conventional treatment. MicroRNAs are a class of small noncoding RNAs that function as critical gene regulators through targeting mRNAs, causing translational repression or degradation. In this study, we showed that miR-217 was down-regulated in osteosarcoma cell lines and tissues in comparison to that in normal bone cells or tissues. Meanwhile, the lower level of miR-217 was associated with metastasis in clinical osteosarcoma patients. Furthermore, we found that overexpession of miR-217 markedly suppressed cell proliferation, migration, and invasion of osteosarcoma cells. Conversely, the inhibition of miR-217 expression significantly accelerated the cell proliferation, migration, and invasion. Moreover, we identified WASF3 as a novel functional downstream target of miR-217. The ectopic expression of WASF3 can partially reverse the inhibition of cell proliferation and invasion caused by miR-217. Take together, our results demonstrate that miR-217 functions as a tumor-suppressive miRNA and inhibits the osteosarcoma tumorigenesis through targeting WASF3.
Both heavy metals and antibiotics exert selection pressure on bacterial resistance, and as they are commonly co-contaminated in the environment, they may play a larger role in bacterial resistance. ...This study examined how breeding cycles affect antibiotic resistance genes (ARGs) in chicken manure and the surrounding topsoils at 20, 50, 100, 200, and 300 m from twelve typical laying hen farms in the Ningxia Hui Autonomous Region of northwest China. Six antibiotics, seven heavy metals, ten mobile genetic elements (MGEs), and microbial community affected the ARGs profile in chicken dung and soil samples. Tetracycline antibiotic residues were prevalent in chicken manure, as were relatively high content of aureomycin during each culture period. Zinc (Zn) content was highest among the seven heavy metals in chicken feces. Chicken dung also enriched aminoglycosides, MLSB, and tetracycline ARGs, notably during brooding and high production. The farm had a minimal influence on antibiotics in the surrounding soil, but its effect on ARGs and MGEs closer to the farm (50 m) was stronger, and several ARGs and MGEs increased with distance. Manure microbial composition differed dramatically throughout breeding cycles and sampling distances. ARGs were more strongly related with antibiotics and heavy metals in manure than soil, whereas MGEs were the reverse. Antibiotics, heavy metals, MGEs, and bacteria in manure accounted 12.28%, 22.25%, 0.74%, and 0.19% of ARGs composition variance, respectively, according to RDA and VPA. Bacteria (2.89%) and MGEs (2.82%) only affected soil ARGs composition. These findings showed that heavy metals and antibiotics are the main factors affecting faecal ARGs and bacteria and MGEs soil ARGs. This paper includes antibiotic resistance data for large-scale laying hen husbandry in northwest China and a theoretical framework for decreasing antibiotic resistance.
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•The distribution of antibiotics and heavy metals in chicken manure and surrounding soil.•Chicken farms have a larger effect on ARGs in soils closer to the surrounding area (≤50 m).•Antibiotics and heavy metals were more closely associated with ARGs in chicken manure than in soil.•The pattern of co-occurrence between MGEs and ARGs was significantly stronger in soil than in chicken manure.•Heavy metals and antibiotics were the main factors influencing the composition of ARGs in chicken manure.
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