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In this work, we developed an efficient electrochemical exfoliation strategy for the preparation of graphene (eGr) nanosheets. Newly designed nanosheets-like eGr/GCE electrode possessed large specific surface area, low defect and good electrical conductivity, which facilitates the preconcentration of Kinetin (KT) onto the electrode surface. It exhibits a linear range extending from 0.5 to 100 µM and the lowest detection limit at 0.15 µM. The KT oxidation on eGr is an adsorption-controlled process, which involves a total of 4 H+ and 4 e− in the transferring processes. Moreover, there were no significant interfering substances among inorganics (NO3−, Cu2+, K+, PO43−, SO42−, Na+, Cl−), quercetin, rutin, luteolin, luteoloside, naphthylacetic acid, 2,4-dichlorophenoxyacetic acid and indole-3-acetic acid. The recoveries are in the range of 89.6–117.43% with a relative and deviation (RSD) < 4% (n = 3) for KT detection in lettuce. [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides are widely applied to improve the quality and yield of the crop. A sensitive and highly selective electrochemical sensor is required for monitoring their residues. In this paper, nano-structured cerium oxide and multiwall carbon nanotube composite (MWCNTs) were successfully constructed as an electrochemical sensor for nitenpyram (NIT) determination. The developed sensor has a broad linear range from 2 to 180 μM and a low detection limit of 0.72 μM (S/N = 3) for NIT detection under the optimal ratio of 1:1 between CeO2 and MWCNTs. The electrochemical oxidation process of NIT involves one proton and two electron. Moreover, this developed sensor has excellent reproducibility with a relative standard deviation (RSD) of 3.1% in six replicated measurements, and excellent stability with 92.95% current retention after 15 days. In addition, the modified electrode has a good sensitivity and stability for the measurement of NIT in actual samples, it has the recovery ranges of 90.60–97.78% for the determination of NIT in corn extraction and 90.06–114.4% for that of NIT in river water. The proposed CeO2/MWCNTs sensor exhibits a great potential for the quick detection of neonicotinoid insecticides in the agricultural industry. [ABSTRACT FROM AUTHOR]

Internal ribosome entry site (IRES)-dependent translation is a mechanism distinct from 5′ cap-dependent translation. IRES elements are located mainly in the 5′ untranslated regions (UTRs) of viral and eukaryotic mRNAs. However, IRESs are also found in the coding regions of some viral and eukaryotic genomes to initiate the translation of some functional truncated isoforms. Here, five putative IRES elements of human rhinovirus 16 (HRV16) were identified in the coding region of the nonstructural proteins P2 and P3 through fusion with green fluorescent protein (GFP) expression vectors and bicistronic vectors with a hairpin structure. These five putative IRESs were located at nucleotide positions 4286-4585, 5002-5126, 6245-6394, 6619-6718, and 6629-6778 in the HRV16 genome. The functionality of the five IRESs was confirmed by their ability to initiate GFP expression in vitro. This suggests that an alternative mechanism might be used to increase the efficiency of replication of HRV16. [ABSTRACT FROM AUTHOR]

Cellular immune responses, particularly those associated with CD3CD8 cytotoxic T lymphocytes (CTL), are critical factors in controlling viral infection. Nasopharyngeal carcinoma (NPC) is closely associated with persistent Epstein-Barr virus (EBV) infection. NPC vaccine studies have focused on enhancing specific antiviral CTL responses. In this study, three vaccines capable of expressing the EBV-latent membrane protein 2 (LMP2) (a DNA vector, an adeno-associated virus (AAV) vector, and a replication-defective adenovirus serotype 5 (Ad5) vector) were respectively used to immunize female Balb/c mice (4-6 weeks old) at weeks 0, 2 and 4, either alone or in combination. Our results suggest that combined immunization with DNA, AAV, and adenovirus vector vaccines induced specific cellular immunity more effectively than any of these vectors alone or a combination of two of the three, constituting a sound vaccine strategy for the prevention and treatment of NPC. [ABSTRACT FROM AUTHOR]

Epstein-Barr virus (EBV) infection has been causally associated with occurrence of many malignant neoplasms. EBV-encoded small RNAs (EBERs) have been detected from about 10% of gastric carcinoma tissue cells, suggesting that EBV infection is associated with the development of gastric carcinoma. The present study pooled the data from the papers concerning EBV-related gastric cancers and performed a meta-analysis of 22 research papers. Among these papers, a total of 5475 cases with gastric cancer were enrolled, of whom 411 cases were found EBV-positive, with the EBV-positive rate being 7.5%. Among the EBV-positive gastric cancer cases, the detection rate was 11.1% in males and 3.0% in females. Compared with EBV-negative gastric cancer, EBV-positive gastric cancer had less lymph node metastasis. Based on the histological typing, of the EBV-positive gastric cancers, the diffuse type was 8.1%, and intestinal type was 8.0%. The examined specimen types included stored paraffin blocks and fresh surgically removed specimens, their EBV positive rates were 7.9% and 6.5% respectively. In terms of geographical distribution, the detection rate of EBV-positive gastric cancer was 9.4% in America, 6.1% in Asia and 9.1% in Europe. Meta-analysis showed that EBV infection occurred only in gastric cancer tissue cells and was significantly associated with the patients' gender, lymph node metastases, and the location where tumor tissue generated and geographical distribution ( P<0.05), but was not significantly associated with the patients' histological types of tumor and the types of specimens ( P>0.05). These results suggested that EBV-positive gastric cancer has distinct clinicopathological features. [ABSTRACT FROM AUTHOR]

Epoxy resin (EP), as a widely used polymer material, is inherently flammable. Imparting it with high-efficiency flame-retardant properties has always been the focus of attention. In this work, using triallyl isocyanurate (TAIC) and 9,10-dihydro-9-oxa-10-phospha phenanthrene-10-sulfide (DOPS) as raw materials, a novel double-group flame retardant, tris(3-(9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-sulfide)-propyl)triazine-2,4,6-trione(DOPS-TAIC), has been synthesized via a one-step method. Before curing, the structure was characterized by FT-IR, 1H NMR, and 31P NMR. Subsequently, the flame retardant DOPS-TAIC was applied to EP, and a series of testing methods were employed to investigate the effects of DOPS-TAIC on the thermal stability, flame retardancy, and mechanical properties of EP. Furthermore, the flame retardant mechanism of DOPS-TAIC in the gas phase and condensed phase was further explored. The results showed that EP/DOPS-TAIC achieved a UL-94 V-0 rating with an LOI value of 31.6% when added at 12.5 wt%. In addition, the total heat release, peak heat release rate, and average heat release rate (av-HRR) of EP/DOPS-TAIC-12.5 wt% were significantly reduced by 35.05%, 61.83%, and 51.68%, respectively. SEM-EDS results showed that DOPS-TAIC can effectively promote the generation of expanded dense char layers and retain flame retardant elements (P and S) in the char layer. Meanwhile, TG-IR and Py-GC/MS demonstrate their radical quenching effect in the gas phase, indicating that DOPS-TAIC possesses both condensed-phase and gas-phase flame-retardant mechanisms. Therefore, this study provides a simple and effective method for developing flame-retardant epoxy resins.Graphical abstract: Epoxy resin (EP), as a widely used polymer material, is inherently flammable. Imparting it with high-efficiency flame-retardant properties has always been the focus of attention. In this work, using triallyl isocyanurate (TAIC) and 9,10-dihydro-9-oxa-10-phospha phenanthrene-10-sulfide (DOPS) as raw materials, a novel double-group flame retardant, tris(3-(9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-sulfide)-propyl)triazine-2,4,6-trione(DOPS-TAIC), has been synthesized via a one-step method. Before curing, the structure was characterized by FT-IR, 1H NMR, and 31P NMR. Subsequently, the flame retardant DOPS-TAIC was applied to EP, and a series of testing methods were employed to investigate the effects of DOPS-TAIC on the thermal stability, flame retardancy, and mechanical properties of EP. Furthermore, the flame retardant mechanism of DOPS-TAIC in the gas phase and condensed phase was further explored. The results showed that EP/DOPS-TAIC achieved a UL-94 V-0 rating with an LOI value of 31.6% when added at 12.5 wt%. In addition, the total heat release, peak heat release rate, and average heat release rate (av-HRR) of EP/DOPS-TAIC-12.5 wt% were significantly reduced by 35.05%, 61.83%, and 51.68%, respectively. SEM-EDS results showed that DOPS-TAIC can effectively promote the generation of expanded dense char layers and retain flame retardant elements (P and S) in the char layer. Meanwhile, TG-IR and Py-GC/MS demonstrate their radical quenching effect in the gas phase, indicating that DOPS-TAIC possesses both condensed-phase and gas-phase flame-retardant mechanisms. Therefore, this study provides a simple and effective method for developing flame-retardant epoxy resins. [ABSTRACT FROM AUTHOR]

Rice (Oryza sativa L.) paddies are increasingly threatened by cadmium (Cd) pollution, and potentially serve as CH4 emitters to the atmosphere. Remediation agents widely mitigate Cd pollution in paddy soil, however, we know little about their regulations on CH4 emission. Here, via adding biochar (B), sulfhydryl-modified palygorskite (SMP), and selenium foliar fertilizer (SFF), we conducted a pot experiment to investigate soil and rice Cd contents together with in-situ CH4 fluxes. Compared to CK, the addition of SMP, SFF, and B-SMP reduced Cd in brown rice by 25% to 50%, 25%, and 50% to 75%, respectively. Agents 7% B, 7% B-0.01% SMP, and SFF reduced CH4 emissions by 8.46%, 5.30%, and 4.11%, respectively. CH4 emission increased gradually along the growing season, with the cumulative CH4 fluxes ranging between 338.82 and 619.13 kg hm−2. Our results highlight that mixed 7% B-0.01% SMP and SFF showed collaborative effects on Cd remediation and CH4 emission. This study reveals the feasibility of reducing Cd pollution and CH4 emission in karst rice paddies, which hopes to supplement the knowledge of collaborative controls on soil remediation and carbon emission. [ABSTRACT FROM AUTHOR]

The cultivation of Pleurotus eryngii is increasing rapidly in China due to its nutritional and medicinal importance, excellent flavor, and long shelf life; therefore, cheaper and locally available alternative substrates are urgently needed. Experiments were performed to investigate the use of alternative substrates for P. eryngii cultivation. Korshinsk peashrub (Caragana korshinskii Kom.), a perennial shrub, was included in the substrate at varying rates to substitute for the sawdust and sugarcane bagasse (21/38 and 21/35%, respectively) in the typical substrate. The cultivation substrate including 38% Korshinsk peashrub did not significantly affect linear mycelial growth. The fruit body yield (247.3 g/bag) and biological efficiency (70.66%) achieved by using this substrate were significantly higher than those achieved using the control substrate (229.6 g/bag and 65.59%). Crude polysaccharide content was highest (6.12%) in the mushroom grown on 38% Korshinsk peashrub substrate; in this mushroom, crude polysaccharide content was increased by 70.47% compared with that of the mushroom grown on the control substrate (3.59%). These results reveal that supplementing the substrate in which P. eryngii is grown with Korshinsk peashrub can improve polysaccharose accumulation by P. eryngii. The findings described above reveal that Korshinsk peashrub is an efficient, cost-effective, and promising substrate additive that can improve P. eryngii quality and yield while largely substituting for sawdust and sugarcane bagasse. [ABSTRACT FROM AUTHOR]

An in situ pyrolysis process of high moisture content lignite in an autogenerated steam agent was proposed. The aim is to utilize steam autogenerated from lignite moisture as a reactant to produce fuel gas and additional hydrogen. Thermogravimetric analysis revealed that mass loss and maximum mass loss rate increased with the rise of heating rates. The in situ pyrolysis process was performed in a screw kiln reactor to investigate the effects of moisture content and reactor temperature on product yields, gas compositions, and pyrolysis performance. The results demonstrated that inherent moisture in lignite had a significant influence on the product yield. The pyrolysis of L (raw lignite with a moisture content of 36.9 %, wet basis) at 900 °C exhibited higher dry yield of 33.67 mL g and H content of 50.3 vol% than those from the pyrolysis of the predried lignite. It was also shown that increasing reaction temperature led to a rising dry gas yield and H yield. The pyrolysis of L showed the maximum dry yield of 33.7 mL g and H content of 53.2 vol% at 1,000 °C. The LHV of fuel gas ranged from 18.45 to 14.38 MJ Nm when the reactor temperature increased from 600 to 1,000 °C. [ABSTRACT FROM AUTHOR]