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1.
J Hazard Mater ; 401: 123444, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-32763719

RESUMO

Hydrothermal instability restricts performances of silica-based catalysts, which have wide applications in both industry and environment. For the first time, plasma-thermal slag was revealed to be a catalyst with a born hydrothermal stability in selective catalytic reduction of nitric oxide. The slag catalyst removed 98.5 % of NO with a high N2 selectivity (> 95 %) at 200 °C. After a hydrothermal treatment at 900 °C, the activity of the slag only decreased to 84.0 %. According to characterizations of XRD, HTREM, XPS, and EPR, active metals existed in coordination states in the slag at first. Under hydrothermal conditions, these species transformed to short-range single crystals, which were hindered from sintering by surrounded Si-O bands. At the same time, in-situ DRIFT indicated that more Brønsted and Lewis acid sites were formed. Hence, enough active sties were reserved for effective catalytic reduction of nitric oxide. The main result of this work helps us to understand hydrothermal stability of a catalyst. What's more, the high-value-added utilization of plasma-thermal slag is in favor of the development of hazardous-waste treatment.

2.
Ultrason Sonochem ; 70: 105300, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32763750

RESUMO

Vacuum freeze-drying is a new and high technology on agricultural product dehydrating dry, but it faces the high cost problem caused by high energy consumption. This study investigated the effect of ultrasound (US), freeze-thawing (including the freeze-air thawing (AT), freeze-water thawing (WT), freeze-ultrasound thawing (UST), and freeze-air ultrasound thawing (AT + US)) pretreatments on the vacuum freeze-drying efficiency and the quality of dried okra. The results indicated that the application of ultrasound and different freeze-thawing pretreatments reduced the drying time by 25.0%-62.50% and the total energy consumption was 24.28%-62.35% less. The AT pretreatment reduced the time by of okra slices by 62.50% and the total energy consumption was 62.35% less. The significant decrease in drying time was due to a change in the microstructure caused by pretreatment. Besides, the okra pretreated with the US retained most of the quality characteristics (flavor, color, hardness, and frangibility) among all methods, while, AT + US had the most changeable characteristics in quality, which is deprecated in our study. The okra pretreated with the US and AT, separately, had the best dry matter content loss (9.008%, 5.602%), lower chlorophyll degradation (5.05%, 5.44% less), and higher contents of total phenolics, total flavonoids, and pectin, with strong antioxidant capacity, compared to other methods. The pretreatments did not have a large effect on the functional groups and the structure of pectin, but slightly affected the viscosity. It can be concluded that AT and US pretreatment methods are better than others.

3.
Ultrason Sonochem ; 70: 105347, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32956936

RESUMO

As a non-thermal processing method, the ultrasound treatment prior to the frying process has been demonstrated with great potential in reducing the oil absorption of fried food. This research aimed to evaluate the effect of ultrasound pretreatment on starch properties, water status, pore characteristics, and the oil absorption of potato slices. Ultrasound probe set with two power (360 W and 600 W) at the frequency of 20 kHz for 60 min was applied to perform the pretreatments. The results showed that ultrasound pretreatment led to the surface erosion of starch granules and higher power made the structure of starch disorganized. Moreover, the fraction of bound water and immobilized water were changed after ultrasonic pretreatment. Pores with the minor diameters (0.4-3 µm and 7-12 µm) were formed after ultrasound pretreatment. The penetrated surface oil (PSO) content, and structure oil (STO) content were reduced by 27.31% and 22.25% respectively with lower power ultrasound pretreatment. As the ultrasound power increased, the surface oil (SO) content and PSO content increased by 25.34% and 12.89% respectively, while STO content decreased by 38.05%. By using ultrasonic prior to frying, the quality of potato chips has been greatly improved.

4.
Food Chem ; 337: 127921, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32919266

RESUMO

Antioxidant peptides obtained from snakehead (Channa argus) soup (SHS) after simulated gastrointestinal (GI) digestion were separated, identified and characterized. Results showed that the fraction with MW < 3 kDa had the highest antioxidant capacity. Four novel antioxidant peptides were identified after RP-HPLC and UPLC-MS/MS. PGMLGGSPPGLLGGSPP and SDGSNIHFPN had the highest DPPH radical scavenging activity (IC50 = 1.39 mM) and Fe2+ chelating ability (IC50 = 4.60 mM), respectively. Structures in silico for IVLPDEGK, PGMLGGSPPGLLGGSPP and SDGSNIHFPN suggest at least one ß-turn and/or α-helix, which are associated with antioxidant activity. Moreover, our results showed that these three peptides docked with a recombinant Kelch-like ECH-associated protein 1 (Keap1) with a binding score greater than TX6, a good ligand of Keap1. The cell viability assay also showed significant cytoprotective effects against H2O2-induced cellular oxidative damage. This information implies that antioxidant mechanisms of novel SHS peptides occurred via activation of cellular anti-oxidation Keap1-Nrf2 signaling pathway.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 244: 118854, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-32920500

RESUMO

Extraction process is not only a critical manufacturing unit but also the initial process of various extracts and preparations. Taking the most extensive Chinese herbal medicine Danshen (Salvia miltziorrhiza Bge) as an example, salvianolic acid B (Sal B) is its main active pharmaceutical ingredient but lacks accurate characterization of the extraction process. As one of process analytical technologies, near-infrared spectroscopy (NIRS) technology has been widely applied for monitoring pharmaceutical extraction process. In most past studies, water spectral information is often eliminated due to its high absorption. However, this study proposed a method of using water spectrum to understand the whole extraction process and to quickly determine the content of Sal B. Principal component analysis (PCA) was first utilized to investigate the whole extraction process, then the reconstructed spectrum based on PCA was established and analyzed by Aquaphotomics, and finally the partial least squares regression (PLSR) quantitative model of Sal B was established. PCA and Aquaphotomics results showed the whole extraction process could be considered as a dynamic change from structure breaker to structure maker, and the dominance of highly H-bonded water structures increases with the extraction time. Also, the Sal B quantitative model with water spectrum showed higher accuracy and stability than other methods, which parameters (RMSEC, RMSECV, RMSEP, R2c, R2cv, R2p, RPD) were 0.2408 mg/mL, 0.2939 mg/mL, 0.2584 mg/mL, 0.9536, 0.9300, 0.9494, 4.6298, respectively, and the paired t-test showed that Sal B content measured by NIR and HPLC methods had no significant differences (p > 0.05). In conclusion, all result indicated that water can be used as a probe to understand the traditional Chinese medicine extraction process with NIRS.

6.
Talanta ; 221: 121477, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33076090

RESUMO

Due to the potential threats of phosgene and nitrite to public health and safety, in this work, we first proposed the application of a facile dual-function fluorescent probe 2-(1H-Benzimidazol-2-yl)Aniline (BMA) for the detection of phosgene and nitrite in different solvent environments. BMA had fast response (1 min), high selectivity and sensitivity (the limit of detection was 1.27 nM) to phosgene in CH3CN solution (containing 10% DMSO), which manifested as a ratiometric fluorescent mode from 416 nm to 480 nm. The response of BMA to nitrite in HCl solution (pH = 1, containing 10% CH3CN) was also highly selective and sensitive (the limit of detection was 60.63 nM), which shown as a turn-off fluorescent mode at 485 nm. In addition, two portable chemosensors (BMA-loaded TLC plates and test strips) had also been successfully manufactured for the detection of phosgene in the gas phase and nitrite in solution, which displayed good responses. Most importantly, BMA had also been successfully used for detection of nitrite in food samples, and a good recovery (88.5%-107.2%) was obtained by adding standard sodium nitrite.

7.
Biochim Biophys Acta Mol Cell Res ; 1868(1): 118858, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32950569

RESUMO

Protein phosphatase 2A (PP2A) complex comprises an extended family of intracellular protein serine/threonine phosphatases, that participate in different signaling transduction pathways. Different functions of PP2As are determined by the variety of regulatory subunits. In this study, CRISPR/Cas9-mediated loss-of-function screen revealed that PPP2R2A downregulation suppressed cell growth in NSCLC cells. AMOTL2 was identified and confirmed as a novel binding partner of PPP2R2A in NSCLC cells by mass spectrometry, CO-IP, GST pull-down and immunofluorescence. Upregulation of AMOTL2 also led to cell proliferation delay in human and mouse lung tumor cells. The proto-oncogene JUN is a key subunit of activator protein-1 (AP-1) transcription factor which plays crucial role in regulating tumorigenesis and its activity is negatively regulated by the phosphorylation at T239. Our results showed that either AMOTL2 upregulation or PPP2R2A downregulation led to great increase in JUN T239 phosphorylation. AMOTL2 bound PPP2R2A in cytoplasm, which reduced nuclear localization of PPP2R2A. In conclusion, AMOTL2 and PPP2R2A act respectively as negative and positive regulator of cell growth in NSCLC cells and function in the AMOTL2-PPP2R2A-JUN axis, in which AMOTL2 inhibits the entry of PPP2R2A into the nucleus to dephosphorylate JUN at T239.

8.
Sci Total Environ ; 752: 141964, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32892055

RESUMO

The current study presents the first nitrogen (N) and phosphorus (P) footprints calculator for Sub-Saharan Africa during 1961-2017 using an adjusted N-Calculator model, by calculating two sets of virtual N factors (VNFs) or virtual P factors (VPFs): one for fertilized farms and one for unfertilized farms. We furthermore calculated the future food footprints of N (NF) and P (PF) under five scenarios include: 1) business as usual [BAU], 2) achieve an equitable diet (EqD) while the plant N and P uptake and all other food losses would be constant at 2017 level [S1], 3) follow the EqD without any changes in plant N and P uptake, but the current ratio of other food losses would increase by 50% [S2], 4) follow the EqD with a 5% less in plant N and P uptake than the current ratio, and the current ratio of other food losses would increase by 50% [S3], and 5) follow the EqD with a 10% greater in plant N and P uptake than the current ratio, while the current ratio of other food losses would decrease by 50% [S4]. NF (kg N cap-1 yr-1) and PF (kg P cap-1 yr-1) increased from 6.7 and 1.1 to 8.3 and 1.5 during 1961-2017, respectively. The national NF (Tg N yr-1) and PF (Tg P yr-1) increased from 1.6 and 0.26 to 7.7 and 1.4, respectively. In 2050, NF would be 9.7, 21.7, 24.1, 27.7, and 15.5 kg N cap-1 yr-1 for the BAU, S1, S2, S3, and S4 scenarios, respectively. While, PF would be 1.8, 5.1, 5.6, 7.3, and 3.0 kg P cap-1 yr-1, respectively. S4 scenario results in much less NF and PF. We suggest applying the S4 scenario with a change of dietary style by reducing the foods consumption with high VNFs and VPFs by 2050.

10.
Nat Commun ; 11(1): 6088, 2020 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-33257668

RESUMO

The mechanistic target of rapamycin complex 1 (mTORC1) integrates growth, nutrient and energy status cues to control cell growth and metabolism. While mTORC1 activation at the lysosome is well characterized, it is not clear how this complex is regulated at other subcellular locations. Here, we combine location-selective kinase inhibition, live-cell imaging and biochemical assays to probe the regulation of growth factor-induced mTORC1 activity in the nucleus. Using a nuclear targeted Akt Substrate-based Tandem Occupancy Peptide Sponge (Akt-STOPS) that we developed for specific inhibition of Akt, a critical upstream kinase, we show that growth factor-stimulated nuclear mTORC1 activity requires nuclear Akt activity. Further mechanistic dissection suggests that nuclear Akt activity mediates growth factor-induced nuclear translocation of Raptor, a regulatory scaffolding component in mTORC1, and localization of Raptor to the nucleus results in nuclear mTORC1 activity in the absence of growth factor stimulation. Taken together, these results reveal a mode of regulation of mTORC1 that is distinct from its lysosomal activation, which controls mTORC1 activity in the nuclear compartment.

11.
Phytochemistry ; 181: 112588, 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33232863

RESUMO

Plant polyphenol oxidases (PPOs) are ubiquitous copper metalloenzymes with a biochemistry that has been known for more than a century. By the 1990s, biologists began to recognize the importance of PPOs in plant response to the infestation of herbivores and pathogens; ideas concerning a defensive role for PPOs arose to address observed evidence, and several testable hypotheses were suggested. Two pivotal discoveries in tomato (Lycopersicon esculentum Miller) plants, an inverse correlation between PPO levels and insect growth and PPO induction by defence signals, have driven many studies of PPO defence functions in the context of abiotic and biotic stresses. During the past three decades, extensive molecular research in transgenic and non-transgenic systems has partly revealed the sophisticated mechanisms underlying PPO defence against herbivores and pathogens. These understandings, rather than theoretical predictions, have driven the development of new hypotheses and advanced PPO-related studies. Here, we review progress in PPO family features, expression regulation and the defensive role of PPOs in plants. We propose assumptions of an extended range of co- and post-transcriptional processes to the regulation of unexplored PPO expression. In addition, the identification of endogenous PPO substrates and downstream targets of PPO action will be useful for elucidating PPO defensive roles. The potential effects of PPO-mediated oxidative defences on herbivore performance ultimately needs to be further investigated. Therefore, expanding multidisciplinary approaches to unexplored dimensions of PPO defence function should be a future priority.

12.
Bioorg Med Chem ; 29: 115876, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33246255

RESUMO

DDR1 is a receptor tyrosine kinase that is activated by triple-helical collagens and has become an attractive target for anticancer therapy given its involvement in tumor growth, metastasis development, and tumor dormancy. Several drugs on the market, such as dasatinib and nilotinib, were reported to potently suppress the function of DDR1 and show significant therapeutic benefits in a variety of preclinical tumor models. Whereas only a few selective DDR1 inhibitors were disclosed in recent years. A series of 4-amino-1H-pyrazolo[3,4-d]pyrimidin derivatives were designed and synthesized. All compounds were evaluated via DDR1 kinase inhibition assay and cell anti-proliferative assay. One of the representative compounds, 6c, suppressed DDR1 kinase activity with an IC50 value of 44 nM and potently inhibited cell proliferation in DDR1-overexpressing cell lines HCT-116 and MDA-MB-231 with IC50 value of 4.00 and 3.36 µM respectively. Further molecular docking study revealed that 6c fitted ideally into DDR1 binding pocket and maintained the crucial hydrogen bonds with DDR1 kinase domain. Overall, these results suggest that the compound 6c is a potential DDR1 inhibitor deserving further investigation for cancer treatment.

13.
Thyroid ; 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33138723

RESUMO

BACKGROUND: Malnutrition in early life may permanently change the structure and function of the body, which lead to a number of diseases in adulthood. The effect of famine exposure during the early life on thyroid function and disorders remains unclear. This study investigated the association between exposure to the Great Chinese Famine (1959-1961) in early life and thyroid function and disorders in adulthood. METHODS: 9881 subjects with appropriate birth dates derived from the Thyroid disorders, Iodine status and Diabetes Epidemiological survey were included. Thyroid function and disorders were defined by the test results of blood sample and ultrasonography of all participants. Associations between famine exposure in early life and thyroid function and disorders in adulthood were assessed with binary logistic regression and linear regression. RESULTS: Participants exposed to the Great Chinese Famine during the fetal stage was associated with a higher TSH level in adulthood (ß = 0.024; P = 0.038), compared with the non-exposed participants. The association was significant among rural participants (ß = 0.039; P = 0.02) but not in urban participants (ß = 0.005; P =0.77). Fetal-exposed group did not show a higher risk of thyroid disorders than the age-balanced control group, including overt hyperthyroidism, subclinical hyperthyroidism, overt hypothyroidism, subclinical hypothyroidism, autoimmune thyroiditis, and thyroid nodules (P > 0.05). CONCLUSIONS: Famine exposure during the fetal stage was associated with a higher TSH level in adulthood. The fetal stage could be the critical period for programming the pituitary-thyroid axis.

14.
Tree Physiol ; 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33147625

RESUMO

In trees, wood formation needs carbon import from the photosynthetic source tissues. Sugar transporters play important roles in carbohydrate transport into wood-forming cells. SWEETs (Sugars Will Eventually be Exported Transporters) play essential roles in many physiological processes. However, the roles of this family in the growth and development of woody plants have not been systematically investigated. In this study, 27 SWEET genes were identified in the Populus trichocarpa genome. These SWEET genes were classified into four clades based on their phylogenetic relationships, gene structures, conserved motifs, and chromosomal locations. Representative SWEET members from each clade were selected for further studies. The PagSWEETs were localized to plasma membrane, vacuolar, endoplasmic reticulum (ER) or Golgi. Real-time quantitative PCR analysis showed that PagSWEETs have distinct expression patterns in various tissues, and PagSWEET5, 7, 10b, 10c, 15b, 17a, and 17c exhibited high expression levels in stems. PagSWEET7 is localized to the cytoplasmic membrane and specifically expressed in the phloem as detected by histochemical GUS assays. Xylem production and xylem sugar content were greater in developing wood of SWEET7 overexpression (OX) than Wild-type (WT) lines. Collectively, these results provide valuable information for further investigating functions of PagSWEET genes, and identify PagSWEET7 as a candidate gene for using biotechnology to modify the wood formation in poplar.

15.
Life Sci ; : 118641, 2020 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-33148420

RESUMO

Pancreatitis is an inflammatory disease of the pancreas characterized by acinar cell injury and is associated with the abnormal release of trypsin, which results in high mortality due to systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS). The inflammatory response, impaired autophagic flux, endoplasmic reticulum stress (ERS) and their interactions are involved in the development of pancreatitis. Molecular hydrogen (H2) is a novel antioxidant that possesses the features of selective scavenging of oxygen free radicals and nontoxic metabolites and has been shown to be efficacious for treating infection, injury, tumors, ischemia-reperfusion organ injury, metabolic disease and several other diseases. Recent studies have found that H2 is also useful in the treatment of pancreatitis, which may be related to the mechanism of antioxidative stress, anti-inflammation, anti-apoptosis, regulation of immunity and regulation of molecular pathways. This review focuses on the pathogenesis of pancreatitis and the research progress and potential mechanisms of H2 against pancreatitis to provide theoretical bases for future research and clinical application of H2 therapy for pancreatitis.

16.
Reprod Sci ; 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33151524

RESUMO

Type 2 diabetes mellitus (T2DM) is a disease characterized by hyperglycemia resulting from insulin resistance. In recent years, the incidence of T2DM has been increasing. Women with T2DM often suffer from infertility and early miscarriage; however, the underlying mechanisms remain unclear. Insulin is the most important regulatory hormone of glycogen metabolism. In addition, 5' adenosine monophosphate-activated protein kinase (AMPK) is an important regulator of glycogen metabolism. Patients with T2DM have inhibited AMPK expression in the liver, which leads to impaired glucose metabolism. However, the role of AMPK in endometrial glycogen metabolism has not been reported. In this study, a mouse model of T2DM was established to investigate whether altered endometrial glucose metabolism affects early embryo implantation. Metformin and insulin were used for therapy; the resulting changes to glycogen metabolism and embryo implantation were examined. The results indicate that the concentrations of glycogen decreased significantly in T2DM mice, resulting in insufficient energy supplies for proper endometrial function, and thereby impeding embryonic implantation. Interestingly, endometrial AMPK was not found to be overactivated. Insulin treatment was found to partially resolve the embryo implantation defects in T2DM mice. Metformin improved blood glucose but did not have a significant effect on local endometrial glucose metabolism. This study explored the changes in endometrial glucose metabolism in T2DM mouse, and the effects of these changes on embryo implantation. We found that insulin, but not metformin, significantly resolved embryo implantation problems. These findings will help to increase our understanding of the pathomechanisms of infertility and early miscarriage in women with T2DM.

17.
J Cell Physiol ; 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33184860

RESUMO

Morphine, a mu-opioid receptor (MOR) agonist, has been extensively used to treat advanced cancer pain. In particular, in patients with cancer metastasis, both morphine and anticancer drugs are given simultaneously. However, evidence showed that morphine might be a risk factor in promoting the tumor's malignant potential. In this study, we report that treatment with morphine could activate MOR and lead to the promotion of proliferation, migration, and invasion in HCT116 and DLD1 colorectal cancer (CRC) cells with time-concentration dependence. Moreover, morphine can also contribute to cetuximab's drug resistance, a targeted drug widely used to treat advanced CRC by inducing the activation of epidermal growth factor receptor (EGFR). The cell phenotype includes proliferation, migration, invasion, and drug resistance, which may be reversed by MOR knockdown or adding nalmefene, the MOR receptor antagonist. Receptor tyrosine kinase array analysis revealed that morphine selectively induced the transactivation of EGFR. EGFR transactivation resulted in the activation of ERK1/2 and AKT. In conclusion, morphine induces the transactivation of EGFR via MOR. It activates the downstream signal pathway AKT-MTOR and RAS-MAPK, increases proliferation, migration, and invasion, and promotes resistance to EGFR inhibitors in a CRC cell line. Furthermore, we verified that EGFR inhibition by cetuximab strongly reversed the protumoral effects of morphine in vitro and in vivo. Collectively, we provide evidence that morphine-EGFR signaling might be a promising therapeutic target for CRC patients, especially for cetuximab-resistant CRC patients.

18.
Allergy ; 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33185910

RESUMO

The pandemic of coronavirus disease 2019(COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused an unprecedented global social and economic impact, and high numbers of deaths. Many risk factors have been identified in the progression of COVID-19 into a severe and critical stage, including old age, male gender, underlying comorbidities such as hypertension, diabetes, obesity, chronic lung disease, heart, liver and kidney diseases, tumors, clinically apparent immunodeficiencies, local immunodeficiencies, such as early type-I interferon secretion capacity, and pregnancy. Possible complications include acute respiratory distress syndrome, shock, disseminated coagulopathy, acute kidney injury, pulmonary embolism, and secondary bacterial pneumonia. The development of lymphopenia and eosinopenia are laboratory indicators of COVID-19. Laboratory parameters to monitor disease progression include lactate dehydrogenase, procalcitonin, high-sensitivity C-reactive protein, proinflammatory cytokines such as interleukin (IL)-6, IL-1ß, Krebs von den Lungen-6 (KL-6) and ferritin. The development of a cytokine storm and extensive chest computed tomography imaging patterns are indicators of a severe disease. In addition, socioeconomic status, diet, lifestyle, geographical differences, ethnicity, exposed viral load, day of initiation of treatment, and quality of health care have been reported to influence individual outcomes. In this review, we highlight the scientific evidence on the risk factors of severity of COVID-19.

19.
Sci Total Environ ; : 143473, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33203566

RESUMO

Animal manures are commonly applied to soil which possibly promote the spread of antibiotic resistance from soil to human beings via food chains. Biogas slurry is an end product of anaerobic digestion of animal manures, which has been widely applied as fertilizers in the agricultural soil. However, effect of long-term biogas slurry application on the soil antibiotic resistance and the associated mechanism still remains unclear. The present study characterized antibiotics, antibiotic resistance genes (ARGs), mobile genetic elements (MGEs) and bacterial community, in different agricultural soils unamended (BS-) and amended (BS+) with biogas slurry (8-18 years) in five field experiments. Our results indicated that long-term application of biogas slurry largely increased the concentrations of tetracyclines in soils, and greatly increased the abundances of ARGs, transposase gene (Tn916/1545) and ARGs-associated bacteria. Long-term application of biogas slurry led to tetracyclines accumulation and ARGs enrichment in agricultural soil, and the selection pressure from tetracyclines and the increase of Tn916/1545 abundace become potential contributors for the increase of soil antibiotic resistance via promoting the enrichment of ARG-associated bacteria. The results of the present study should be taken into consideration to develop policy and practice for mitigating the enrichment and spread of antibiotic resistance during the recycling of biogas slurry into agricultural soil.

20.
Nano Lett ; 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33166145

RESUMO

Nanoscale charge control is a key enabling technology in plasmonics, electronic band structure engineering, and the topology of two-dimensional materials. By exploiting the large electron affinity of α-RuCl3, we are able to visualize and quantify massive charge transfer at graphene/α-RuCl3 interfaces through generation of charge-transfer plasmon polaritons (CPPs). We performed nanoimaging experiments on graphene/α-RuCl3 at both ambient and cryogenic temperatures and discovered robust plasmonic features in otherwise ungated and undoped structures. The CPP wavelength evaluated through several distinct imaging modalities offers a high-fidelity measure of the Fermi energy of the graphene layer: EF = 0.6 eV (n = 2.7 × 1013 cm-2). Our first-principles calculations link the plasmonic response to the work function difference between graphene and α-RuCl3 giving rise to CPPs. Our results provide a novel general strategy for generating nanometer-scale plasmonic interfaces without resorting to external contacts or chemical doping.

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