Graphene oxide/polyamidoamine dendrimers (GO/PAMAMs) were prepared via a "grafting to" method. The adsorption behavior of the GO/ PAMAMs for Pb(II), Cd(II), Cu(II), and Mn(II) was studied, and the effects of solution pH, adsorption time, and initial metal ion concentration on adsorption capacity of the adsorbent were also investigated. The pseudo-first-order and pseudo-second-order kinetic models were used to describe the kinetic processes, and the results indicated that the adsorption of Pb(II), Cd(II), Cu(II), and Mn(II) followed a second-order type reaction kinetics and the adsorption of Pb(II), Cd(II), Cu(II), and Mn(II) onto GO/PAMAMs is a chemical adsorption. The adsorption capacities of GO/PAMAMs were found to be 568.18, 253.81, 68.68, and 18.29 mg/g for Pb(II), Cd(II), Cu(II), and Mn(II), respectively. The adsorption reached equilibrium within 60 min and characteristics of the adsorption process were evaluated by using the Langmuir and Freundlich isotherm models. The adsorption processes fit better with the Langmuir model for Cu(II) and Mn(II) than for Pb(II) and Cd(II); the adsorption of Cu(II) and Mn(II) on GO/PAMAMs was a typical monomolecular layer adsorption. ■ INTRODUCTIONThere are plenty of mineral resources in Western Hunan in China; however, a lot of wastewater and waste residue containing heavy metal ions affect sustainable exploitation and utilization of the mineral resources. Water pollution by heavy metal ions has become an urgent problem to be solved.Adsorptive removal of heavy metal ions has been widely applied using such materials as activated carbon, 1−4 multiwalled carbon nanotubes, 5−8 zeolites, 9−12 chitosan, 13−20 metal oxide, 21,22 polymer absorbents, 23 and agricultural byproducts. 24,25 Recently, some effective adsorbents based on graphene and graphene composites were made and applied in removing heavy metal ions. 26−34 For example, the polypyrrole− reduce graphene oxide composite showed a highly selective removal capacity with a high Hg 2+ adsorption capacity of 980 mg·g −1 and an extremely high desorption rate of up to 92.3 %, showing practical utility for wastewater treatment. 26 Graphene oxide (GO) aerogels prepared by a unidirectional freeze-drying method were used as an effective adsorbent for Cu 2+ removal from water. 28 Deng et al. found that the functionalized graphene could be fabricated by a simple and fast method of electrolysis with potassium hexafluorophosphate solution as electrolyte under the static potential of 15 V; the adsorption processes reached equilibrium in just 40 min and the adsorption isotherms were described well by Langmuir and Freundlich classical isotherms models. 33 Polyamidoamine dendrimers (PAMAMs) are highly reactive because of the presence of a large amount of terminal functional groups. 35,36 Mamadou et al. 37 found that the Cu(II) binding capacities of the EDA core PAMAM dendrimers were much larger and more sensitive to solution pH than those of linear polymers with amino groups, and the metal ion laden dendrimers can be regenerated by decreas...

A serial of cross-linked sodium acrylate and acrylamide copolymer /graphene oxide (P(AANa-co-AM)/GO) hydrogels with different mass ratios of acrylic acid (AA) to acrylamide (AM) and different contents of N,N-methylenebisacrylamide (MBA) were prepared via dispersive polymerization.The prepared hydrogels were characterized by XRD, FT-IR, TGA, SEM, and BET in detail. The removal efficiency of Pb 2+ and Cd 2+ on the P(AANa-co-AM)/GO hydrogel have been improved significantly due to the addition of 1.0wt% of GO. The P(AANa-co-AM)/GO hydrogel with AA/AM=1 and 0.8 wt% of MBA has the highest removal efficiency for Pb 2+ and Cd 2+ and a suitable swelling ratio, which was selected as the adsorbent for systematic adsorption of Pb 2+ and Cd 2+ from aqueous solutions.The adsorption capacity and removal efficiency of Pb 2+ and Cd 2+ on the P(AANa-co-AM)/GO hydrogel were dependent on pH, initial heavy metal ion concentration and adsorbent dosage. The presence of 0.01~0.05 M Mg 2+ or Ca 2+ has obvious effect on the adsorption of Cd 2+ . The adsorption kinetics and adsorption isotherms of Pb 2+ and Cd 2+ on the P(AANa-co-AM)/GO hydrogel followed pseudo-first order model and the Langmuir isotherm model, respectively. The maximum adsorption capacity of Pb 2+ and Cd 2+ on the P(AANa-co-AM)/GO hydrogel were calculated to be 452.3 and 196.4 mg/g at 298 K, respectively. The XPS analysis revealed that the adsorption mechanism of Pb 2+ and Cd 2+ on the P(AANa-co-AM)/GO hydrogel was ascribed to the chelation of -COOwith Pb 2+ and the ion-exchange of -COO -Na + with Cd 2+ , respectively. The P(AANa-co-AM)/GO hydrogel possesses good reusability and excellent fixed-bed column operation performance, which suggests that the P(AANa-co-AM)/GO hydrogel can be considered as a promising adsorbent for removing heavy metal ions from practical wastewater.wastewater. Exposure to Pb 2+ or Cd 2+ can lead to health hazards such as central nervous system damage, kidney and lung damage, anemia, bone lesions and infertility problems, and even cause cancer. 1-3 Removal of heavy metal ions from wastewater has been a hot issue. Various treatment technologies have been applied for removing heavy metal ions such as chemical precipitation, 3 ion-exchange, 4 adsorption, 5,6 flocculation, 7 electrolysis, 8 electrocoagulation 9 and membrane separation, 10-12 etc.Among them, adsorption is considered as a facile and effective technique, 13,14 some adsorbents such as biosorbents, 1 active carbon, 15 inorganic minerals, 16,17 and magnetic composites 5-6,18 have been investigated for removing heavy metal ions from aqueous solution. Generally, the adsorption efficiency depends mainly on the type of adsorbents. Recently, various studies have found that hydrogel adsorbents exhibited super adsorption capacity, wide pH independence, easy regeneration and good reusability for removal of toxic metal ions and dyes from wastewater. [13][14][19][20][21][22] As a novel adsorbent, hydrogels are polymers with three dimensional (3-D) networks which can be formed via physical or chemical...

Phytophthora root and stem rot, a destructive disease of soybean [ Glycine max (L.) Merr.], is caused by the oomycete Phytophthora sojae . However, how the disease resistance mechanisms of soybean respond to P. sojae infection remains unclear. Previously, we showed that GmWRKY31, which interacts with a sucrose non-fermenting-1(SNF1)-related protein kinase (SnRK), enhances resistance to P. sojae in soybean. Here, we report that the membrane-localized SnRK GmSnRK1.1 is involved in the soybean host response to P. sojae . The overexpression of GmSnRK1.1 ( GmSnRK1.1 -OE) increased soybean resistance to P. sojae , and the RNA interference (RNAi)-mediated silencing of GmSnRK1.1 ( GmSnRK1.1 -R) reduced resistance to P. sojae . Moreover, the activities and transcript levels of the antioxidant enzymes superoxide dismutase and peroxidase were markedly higher in the GmSnRK1.1 -OE transgenic soybean plants than in the wild type (WT), but were reduced in the GmSnRK1.1 -R plants. Several isoflavonoid phytoalexins related genes GmPAL , GmIFR , Gm4CL and GmCHS were significantly higher in “Suinong 10” and GmSnRK1.1 -OE lines than these in “Dongnong 50,” and were significantly lower in GmSnRK1.1 -R lines. In addition, the accumulation of salicylic acid (SA) and the expression level of the SA biosynthesis-related gene were significantly higher in the GmSnRK1.1 -OE plants than in the WT and GmSnRK1.1 -R plants, moreover, SA biosynthesis inhibitor treated GmSnRK1.1 -R lines plants displayed clearly increased pathogen biomass compared with H 2 O-treated plants after 24 h post-inoculation. These results showed that GmSnRK1.1 positively regulates soybean resistance to P. sojae , potentially functioning via effects on the expression of SA-related genes and increased accumulation of SA.

As one of the most promising techniques for removal or selectively recovery of heavy metals from the industrial effluents, the adsorption technology has been employed for many years and various adsorbents have been studied, including activated carbon 1-3 , chitosan 4-6 , kaolinite 7-9 , diatomite 10-12 , zeolite [13][14][15] , silica gel 16,17 , alumina 18,19 , functionalized polymers [20][21][22] , zero-valent iron 23,24 and nanomaterials 25 . However, most of these adsorbents are not the ideal choices for their unsatisfied adsorption capacity, insufficient adsorption efficiencies, or high price in application.Recently, graphene and graphene composites have been studied extensively for several applications including the adsorption for the removal and recovery of metal ions [26][27][28][29][30][31][32][33][34][35][36][37][38] . Chang et al. 39 reported the synthesis of graphene sheets by ionic-liquid-assisted electrolysis and its adsorption for Fe(II) with a capacity of 299.3 mg/g. Fan et al. 40 investigated the adsorption properties for Pb(II) of the magnetic chitosan grafted with graphene oxide sheets. Mi et al. 41 reported the synthesis of graphene oxide areogels by a unidirectional freezedrying method and their adsorption performance for Cu(II) in aqueous solution.In this paper, the graphene oxide was reduced by ethylenediamine according to Che's method 42 and the reduced graphene oxide was characterized by Fourier transform infrared spectra (FT-IR), Raman spectra, thermogravimetric analysis (TGA)

Ethylene response factors (ERFs) are involved in biotic and abiotic stress; however, the drought resistance mechanisms of many ERFs in soybeans have not been resolved. Previously, we proved that GmERF113 enhances resistance to the pathogen Phytophthora sojae in soybean. Here, we determined that GmERF113 is induced by 20% PEG-6000. Compared to the wild-type plants, soybean plants overexpressing GmERF113 (GmERF113-OE) displayed increased drought tolerance which was characterized by milder leaf wilting, less water loss from detached leaves, smaller stomatal aperture, lower Malondialdehyde (MDA) content, increased proline accumulation, and higher Superoxide dismutase (SOD) and Peroxidase (POD) activities under drought stress, whereas plants with GmERF113 silenced through RNA interference were the opposite. Chromatin immunoprecipitation and dual effector-reporter assays showed that GmERF113 binds to the GCC-box in the GmPR10-1 promoter, activating GmPR10-1 expression directly. Overexpressing GmPR10-1 improved drought resistance in the composite soybean plants with transgenic hairy roots. RNA-seq analysis revealed that GmERF113 downregulates abscisic acid 8′-hydroxylase 3 (GmABA8’-OH 3) and upregulates various drought-related genes. Overexpressing GmERF113 and GmPR10-1 increased the abscisic acid (ABA) content and reduced the expression of GmABA8’-OH3 in transgenic soybean plants and hairy roots, respectively. These results reveal that the GmERF113-GmPR10-1 pathway improves drought resistance and affects the ABA content in soybean, providing a theoretical basis for the molecular breeding of drought-tolerant soybean.

Phytophthora root and stem rot in soybean [Glycine max (L.) Merr.] is a destructive disease worldwide. Improving soybean resistance to the causal pathogen, Phytophthora sojae, is a major target for breeders; however, it remains largely unclear how the pathogen regulates the various affected signaling pathways in the host, which consist of complex networks including key transcription factors and their targets. We previously demonstrated that GmBTB/POZ enhances soybean resistance to P. sojae and associated defense response. Here, we report that GmBTB/POZ interacts with transcription factor GmAP2 and promotes the ubiquitination of GmAP2. The GmAP2-RNAi transgenic soybean hairy roots exhibited an enhanced resistance to P. sojae, whereas GmAP2-overexpressing hairy roots showed P. sojae hypersensitivity. Subsequently, GmWRKY33 was identified as a target of GmAP2, which represses its expression by directly binding to the GmWRKY33 promoter. GmWRKY33 acts as a positive regulator in the response of soybean to P. sojae. Additionally, the overexpression of GmBTB/POZ released the GmAP2-regulated suppression of GmWRKY33 expression in the GmAP2-OE soybean hairy roots and increased their resistance to P. sojae. Taken together, these results indicate a novel regulatory mechanism, the GmBTB/POZ-GmAP2 modulation of the P. sojae resistance response, which putatively regulates the downstream target gene GmWRKY33 in soybean.

Background: RAR-related orphan receptor C (RORC) plays an important role in autoimmune responses and inflammation. However, its function in cancer immunity is still unclear. Its potential value in cancer immunotherapy (CIT) needs to be further studied.Methods: Expression and clinical data for 33 cancers were obtained from UCSC-Xena. The correlation between RORC expression and clinical parameters was analyzed using the limma software package to assess the prognostic value of RORC. Timer2.0 and DriverDBv3 were used to analyze the RORC mutation and methylation profiles. RORC-associated signaling pathways were identified by GSEA. The correlations of RORC expression with tumor microenvironment factors were further assessed, including immune cell infiltration (obtained by CIBERSORT) and immunomodulators (in pancancer datasets from the Tumor-Immune System Interactions and Drug Bank [TISIDB] database). In addition, the correlations of RORC with four CIT biomarkers (tumor mutational burden, microsatellite instability, programmed death ligand-1, and mismatch repair) were explored. Furthermore, three CIT cohorts (GSE67501, GSE168204, and IMvigor210) from the Gene Expression Omnibus database and a previously published study were used to determine the association between RORC expression and CIT response.Results: RORC was differentially expressed in many tumor tissues relative to normal tissues (20/33). In a small number of cancers, RORC expression was correlated with age (7/33), sex (4/33), and tumor stage (9/33). Furthermore, RORC expression showed prognostic value in many cancers, especially in kidney renal clear cell carcinoma (KIRC), brain lower grade glioma (LGG), and mesothelioma (MESO). The mutation rate of RORC in most cancer types was low, while RORC was hypermethylated or hypomethylated in multiple cancers. RORC was associated with a variety of biological processes and signal transduction pathways in various cancers. Furthermore, RORC was strongly correlated with immune cell infiltration, immunomodulators, and CIT

Graphene oxide/polyamidoamines dendrimers (GO/PAMAMs) composites were synthesized via modifying GO with 2.0 G PAMAM. The adsorption behavior of the GO/PAMAMs for acid Bordeaux B (ABB) was studied and the effects of media pH, adsorption time and initial ABB concentration on adsorption capacity of the adsorbent were investigated. The optimum pH value of the adsorption of ABB onto GO/PAMAMs was 2.5. The maximum adsorption capacity increased from 325.78 to 520.83 mg/g with the increase in temperature from 298 to 328 K. The equilibrium data followed the Langmuir isotherm model better than the Freundlich model. The kinetic study illustrated that the adsorption of ABB onto GO/PAMAMs fit the pseudo-second-order model. The thermodynamic parameters indicated that the adsorption process was physisorption, and also an endothermic and spontaneous process.