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1.
Plant Cell Environ ; 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37151160

RESUMO

In soil, arbuscular mycorrhizal fungi (AMF) meet the roots of both host and presumed nonhost plants, but the interactional mechanisms of AMF with and functional relevance for nonhost plants is little known. Here we show AMF can colonize an individually grown nonhost plant, Arabidopsis thaliana, and suppress the growth of Arabidopsis and two nonhost Brassica crops. This inhibitory effect increased with increasing AMF inoculum density, and was independent of AMF species or nutrient availability. 13 C isotope labeling and physiological analyses revealed no significant carbon-phosphorus exchange between Arabidopsis and AMF, indicating a lack of nutritional function in this interaction. AMF colonization activated the danger-associated peptide Pep-PEPR signaling pathway, and caused clear defense responses in Arabidopsis. The impairment of Pep-PEPR signaling in nonhost plants greatly compromised AMF-triggered defensive responses and photosynthesis suppression, leading to higher colonization rates and reduced growth suppression upon AMF inoculation. Pretreatment with Pep peptide decreased AMF colonization, and largely substituted for AMF-induced growth suppression in nonhosts, confirming that the Pep-PEPR pathway is a key participant in resistance to AMF colonization and in mediating growth suppression of nonhost plants. This work greatly increases our knowledge about the functional relevance of AMF and their mechanisms of interactions with nonhost plants.

2.
Nano Lett ; 23(10): 4431-4438, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37129264

RESUMO

We present a new approach to achieving strong coupling between electrically injected excitons and photonic bound states in the continuum of a dielectric metasurface. Here a high-finesse metasurface cavity is monolithically patterned in the channel of a perovskite light-emitting transistor to induce a large Rabi splitting of ∼200 meV and more than 50-fold enhancement of the polaritonic emission compared to the intrinsic excitonic emission of the perovskite film. Moreover, the directionality of polaritonic electroluminescence can be dynamically tuned by varying the source-drain bias, which induces an asymmetric distribution of exciton population within the transistor channel. We argue that this approach provides a new platform to study strong light-matter interactions in dispersion engineered photonic cavities under electrical injection and paves the way to solution-processed electrically pumped polariton lasers.

3.
Environ Sci Pollut Res Int ; 30(26): 69379-69392, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37133664

RESUMO

The process of industrialization often causes resource depletion and environmental pollution. To shed light on China's resource use and pollution trends in the context of the country's rapid industrial growth, this study analyzes the eco-efficiency of China's industry from 2000 to 2015. We quantify industrial eco-efficiency (IEE) for China and its provinces using data envelopment analysis (DEA) and analyze potential influencing factors at national and regional levels using Tobit regression. IEE in China and in most provinces shows a clear upward trend with some fluctuations, with national scores increasing from 0.394 to 0.704. There is strong regional disparity, with average IEE scores in eastern provinces (0.840) higher than those in central provinces (0.625), which are in turn higher than those in the northeast (0.537) and west (0.438). We next consider potential drivers. Economic development and foreign direct investment (FDI) are positively associated with IEE but appear to show diminishing returns. Environmental enforcement and market for technology are also positively associated with IEE, as expected. The impact of economic development, industrial sector structure, and investment in research and development (R&D) are modified by the stage of industrialization in each region. Targeted measures that can adjust industry structure, enhance environmental enforcement, attract FDI, and increase R&D investment may help further improve IEE in China.


Assuntos
Poluição Ambiental , Tecnologia , Indústrias , Desenvolvimento Industrial , Desenvolvimento Econômico , Eficiência , China
4.
Sci Total Environ ; : 164407, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37244615

RESUMO

Changes of raw materials in China's recycled paper industry after the imported solid waste ban affect products' life-cycle greenhouse gas (GHG) emissions as well. This paper presented a case study of newsprint production with prior- and post-ban scenarios with life cycle assessment, including using imported waste paper (P0) and its three substitutions, i.e., virgin pulp (P1), domestic waste paper (P2), and imported recycled pulp (P3). The function unit is 1 ton of newsprint produced in China, and the study is conducted from cradle to grave which consists pulping and papermaking process, from raw material acquisition to manufacturing, with associated energy production and wastewater treatment, transport, and chemicals production. Our results showed that P1 holds the highest life-cycle GHG emission of 2724.91, followed by 2400.88 from P3. P2 has the lowest emission of 1619.27, only slightly lower than 1742.39 before the ban using route P0 (unit: kgCO2e/ton paper). Scenario analysis showed that current average life-cycle GHG emission for one ton of newsprint is 2049.33 kgCO2e, increased by 17.62 % due to the ban, while this number could be reduced to 12.22 % or even -0.79 % if switching from P1 to P3 and P2. Our study highlighted the importance of domestic waste paper as a promising way to reduce GHG emissions, which still has great potential to increase if with an enhanced waste paper recycling system in China.

5.
J Environ Manage ; 339: 117816, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37043915

RESUMO

Along with the increasing demand for energy and pressure to reduce carbon emissions, floating photovoltaic (FPV) systems are increasingly built on the surface of water bodies with the aim to produce clean energy. However, little is known about how FPV systems influence freshwater ecosystems, e.g., their zooplankton communities. We investigated how rotifer communities responded to FPV systems in subsidence wetlands created by underground coal mining in the North China Plain. Diversity metrics of the rotifer communities were compared between wetlands with and without FPV systems. The density of rotifers was higher in wetlands without FPV systems. In contrast, rotifer diversity as represented by Shannon-Weiner and Pielou evenness indices was higher in the FPV-covered wetlands, while there was no difference in species richness between the two types of wetlands. Furthermore, community structures differed between the two types of wetlands, in large part reflecting differences in the relative abundance of five dominant species found in both types of wetlands. These differences in rotifer assemblages were in large part explainable from environmental changes caused by the FPV panels, notably reduced light availability and water temperature, leading to reduced phytoplankton production. These findings show that FPV systems cause major changes to rotifer communities in these subsidence wetlands and likely in wetlands more generally, and monitoring of the longer-term effects is recommended given the fundamental role of zooplankton in freshwater ecosystems.


Assuntos
Minas de Carvão , Áreas Alagadas , Animais , Ecossistema , China , Água , Zooplâncton
6.
Heliyon ; 9(3): e14649, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37101493

RESUMO

Qingjie-Tuire (QT) granule was approved for clinical use and its combination was reported to treat influenza infection. To explore its active component and mechanism, the components of QT granule were retrieved from UPLC-UC-Q-TOF/MS analysis. The genes corresponding to the targets were retrieved using GeneCards and TTD database. The herb-compound-target network was constructed by Cytoscape. The target protein-protein interaction network was built using STRING database. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of QT granule to IAV were performed for further study. The regulation to different signaling transduction events and cytokine/chemokine expression of QT granule was evaluated using Western blotting and real-time qPCR. Totally, 47 compounds were identified and effect of QT granule on cell STAT1/3 signaling pathways was confirmed by A549 cell model. The efficiency of QT granule on host cell contributes to its clinical application and mechanism research.

8.
Adv Biol (Weinh) ; : e2300056, 2023 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37062755

RESUMO

Bioprinting has attracted extensive attention in the field of tissue engineering due to its unique capability in constructing biomimetic tissue constructs in a highly controlled manner. However, it is still challenging to reproduce the physical and structural properties of native electroactive tissues due to the poor electroconductivity of current bioink systems as well as the limited printing resolution of conventional bioprinting techniques. In this work, an electro-conductive hydrogel is prepared by introducing poly (3,4-ethylene dioxythiophene): poly (styrene sulfonate) (PEDOT: PSS) into an RGD (GGGGRGDSP)-functionalized alginate and fibrin system (RAF), and then electrohydrodynamic (EHD)-bioprinted to form living tissue constructs with microscale resolution. The addition of 0.1 (w/v%) PEDOT: PSS increases the electroconductivity to 1.95 ± 0.21 S m-1 and simultaneously has little effect on cell viability. Compared with pure RAF bioink, the presence of PEDOT: PSS expands the printable parameters for EHD-bioprinting, and hydrogel filaments with the smallest feature size of 48.91 ± 3.44 µm can be obtained by further optimizing process parameters. Furthermore, the EHD-bioprinted electro-conductive living tissue constructs with improved resolution show good viability (>85%). The synergy of the advanced electro-conductive hydrogel and EHD-bioprinting presented here may provide a promising approach for engineering electro-conductive and cell-laden constructs for electroactive tissue engineering.

9.
Sci Total Environ ; 875: 162596, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36898540

RESUMO

With the rise of the aging population, the demand for adult incontinence products keeps increasing in developing countries. The increasing market demand for adult incontinence products will inevitably drive up upstream production, leading to more resources and energy consumption, carbon emissions, and heavier environmental pollution. It is imperative to explore the environmental impact of those products and seek opportunities to reduce the environmental impact, which is insufficient. This study aims to fill the gap in research on comparative analysis of energy consumption, carbon emissions, and the environmental impact of adult incontinence products from a life cycle perspective under different energy saving and emission reduction scenarios in the context of aging in China. Based on empirical data from a top papermaking manufacturer in China, this study applies Life Cycle Assessment (LCA) method to analyze the impact of adult incontinence products from cradle to grave. Then different scenarios in the future are set to explore the potential of and the possible pathways for energy-saving and emission-reduction of adult incontinence products from the perspective of the whole life cycle. The results indicate that the energy and materials inputs are the environmental hotspots of adult incontinence products. Under the future trend of the aging population, the predictable optimization of energy structure, optimization of material composition, and final disposal methods are far from being able to cope with the enormous environmental burden brought by the increase in the consumption of adult incontinence products, especially in 2060 which shows 3.33 to 18.40 times the annual environmental burden under the optimal energy saving and emission reduction scenario, compared to the base year 2020. Research on new environmentally friendly materials and recycling technology should be the focus of the technological development of adult incontinence products.


Assuntos
Meio Ambiente , Poluição Ambiental , Adulto , Humanos , Idoso , Envelhecimento , Carbono , China
10.
Nat Commun ; 14(1): 1433, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36918559

RESUMO

Various topological laser concepts have recently enabled the demonstration of robust light-emitting devices that are immune to structural deformations and tolerant to fabrication imperfections. Current realizations of photonic cavities with topological boundaries are often limited by outcoupling issues or poor directionality and require complex design and fabrication that hinder operation at small wavelengths. Here we propose a topological cavity design based on interface states between two one-dimensional photonic crystals with distinct Zak phases. Using a few monolayers of solution-processed all-inorganic cesium lead halide perovskite quantum dots as the ultrathin gain medium, we demonstrate a lithography-free, vertical-emitting, low-threshold, and single-mode laser emitting in the green. We show that the topological laser, akin to vertical-cavity surface-emitting lasers (VCSELs), is robust against local perturbations of the multilayer structure. We argue that the design simplicity and reduction of the gain medium thickness enabled by the topological cavity make this architecture suitable for low-cost and efficient quantum dot vertical emitting lasers operating across the visible spectral region.

11.
Acta Diabetol ; 60(7): 929-942, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37002321

RESUMO

AIMS: Growing evidence suggests that microRNAs (miRNAs) are crucial in controlling how diabetic retinopathy (DR) develops. We intend to mine miRNAs with diagnostic and predictive value for DR and to investigate new drug therapeutic targets. METHODS: After performing a differential analysis on the miRNA and mRNA datasets for DR and neovascularization (NEO), miRNA-mRNA networks were created. Combine the results of enrichment analysis, Protein-Protein Interaction Networks (PPI), and Cytoscape to identify key miRNAs. DrugBank was used to find drugs that interacted with transcription factors (TF) predicted by TransmiR. Finally, whole blood and clinical data were collected from 58 patients with type 2 diabetes mellitus (T2DM), and RT-qPCR, logistic analysis, and ROC were used to verify the value of key miRNAs. RESULTS: Differential analysis indicated the presence of genes and miRNAs that co-regulate DR and NEO. Enrichment analysis showed that key genes are inextricably linked to neovascularization. Combining the results of PPI and Cytoscape identified four key miRNAs, namely hsa-mir-(4328, 4422, 548z and -628-5p). RT-qPCR, logistic, and ROC results showed that decreased expression levels of hsa-mir-(4328, 4422, 548z and -628-5p) signal the risk of evolution to DR in T2DM patients. Finally, we constructed a TF-miRNA network to find the 15 TFs and the 35 drugs that interact with these TFs. CONCLUSION: hsa-mir-(4328, 4422, 548z and -628-5p) in whole blood are protective factors for DR as novel biomarkers for diagnosis and prediction. In addition, our research provides new drug directions for the treatment of DR, such as Diosmin, Atorvastatin, and so on.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , MicroRNAs , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/etiologia , Biomarcadores
12.
Front Nutr ; 10: 1016243, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36923697

RESUMO

Background: The effect of micronutrients on urologic cancers has been explored in observational studies. We conducted the two-sample mendelian randomization (TSMR) study to investigate whether micronutrients could causally influence the risk of urologic cancers. Methods: Summary statistics for four micronutrients and three main urologic cancers outcomes were obtained from genome-wide association studies (GWAS). MR analyses were applied to explore the potential causal association between them. Sensitivity analyses using multiple methods were also conducted. Results: Genetically predicted one SD increase in serum copper and iron concentrations was causally associated with increased risks of renal cell carcinoma (RCC) (OR = 3.021, 95%CI = 2.204-4.687, P < 0.001, male; OR = 2.231, 95%CI = 1.524-3.953, P < 0.001, female; OR = 1.595, 95%CI = 1.310-1.758, P = 0.0238, male; OR = 1.484, 95%CI = 1.197-2.337, P = 0.0210, female, respectively) and per SD increase in serum zinc levels was related to decreased risks of RCC (OR = 0.131, 95%CI = 0.0159-0.208, P < 0.001, male; OR = 0.124, 95%CI = 0.0434-0.356, P < 0.001, female). No significant results were observed between micronutrients and the risk of bladder cancer after Bonferroni correction. Additionally, per SD increase in serum zinc level was associated with a 5.8% higher risk of prostate cancer (PCa) [OR = 1.058, 95%CI = 1.002-1.116, P = 0.0403, inverse-variance weight (IVW)]. Conclusions: Micronutrients play a vital role in the development of urological tumors. Future studies are required to replicate the findings, explore the underlying mechanisms, and examine the preventive or therapeutic role of micronutrients in clinical settings.

13.
Small ; : e2300162, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36866502

RESUMO

Electrodes made of composites with heterogeneous structure hold great potential for boosting ionic and charge transfer and accelerating electrochemical reaction kinetics. Herein, hierarchical and porous double-walled NiTeSe-NiSe2 nanotubes are synthesized by a hydrothermal process assisted in situ selenization. Impressively, the nanotubes have abundant pores and multiple active sites, which shorten the ion diffusion length, decrease Na+ diffusion barriers, and increase the capacitance contribution ratio of the material at a high rate. Consequently, the anode shows a satisfactory initial capacity (582.5 mA h g-1 at 0.5 A g-1 ), a high-rate capability, and long cycling stability (1400 cycles, 398.6 mAh g-1 at 10 A g-1 , 90.5% capacity retention). Moreover, the sodiation process of NiTeSe-NiSe2 double-walled nanotubes and underlying mechanism of the enhanced performance are revealed by in situ and ex situ transmission electron microscopy and theoretical calculations.

14.
Ann Nucl Med ; 37(4): 238-245, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36723705

RESUMO

PURPOSE: To achieve PET/CT-based preoperative prediction of microvascular invasion in hepatocellular carcinoma by combining the advantages of PET and CT. METHODS: This retrospective study included a total of 100 patients from two institutions who underwent PET/CT imaging. The above patients were divided into a training cohort (n = 70) and a validation cohort (n = 30). This study was based on PET/CT images to evaluate the possibility of microvascular invasion (MVI) of patients. In this study, we proposed a two-branch PET-guided attention network to predict MVI. The model used a two-branch network to extract image features from PET and CT, respectively. The PET-guided attention module aimed to enable the model to focus on the lesion region and reduce the disturbance of irrelevant and redundant information. Model performance was evaluated by the area under the curve (AUC) of the receiver operating characteristic (ROC) curve. RESULTS: The method outperformed the single-modality prediction model for preoperative hepatocyte microvascular invasion, achieving an AUC of 0.907. On the validation set, accuracy reached 0.846, precision reached 0.881, recall 0.793, and F1-score 0.835. CONCLUSION: The model exploits the particularities of the molecular metabolic function of PET and the anatomical structure of CT and can strongly improve the accuracy of clinical diagnosis of MVI.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Estudos Retrospectivos , Curva ROC , Invasividade Neoplásica
15.
ACS Appl Mater Interfaces ; 15(10): 13618-13624, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36854049

RESUMO

The development of energetic materials with both high energy and high safety has always been the focus of the field of energetic materials. In this paper, a low-current-sensitivity flexible energetic film composed of carbon nanofibers (CNFs)-coated Al/CuO metastable intermolecular composites (MICs) was prepared by a blow-spinning combined with controlled heat treatment technique. Hotspots can hardly generate in this kind of energetic film due to the increased electrical and thermal conductivity, leading to low sensitivity of MICs. It evenly stays at a high voltage (60 V) for 24 h without raising the temperature significantly. The energetic films keep the high energy release of MICs due to the additional violent reactions between CuO and CNFs as well as the light weight of CNFs, showing the heat release of 2864 J/g. In addition, the obtained films exhibit good mechanical properties and can maintain the structural integrity after 1000 cycles of repeated bending to a 6 mm curvature radius. The above characteristics reveal that energetic films presented in this paper have certain safety, high energy, and flexibility and have potential applications in transient electronics with flexible requirements such as micro-electromechanical system.

16.
J Oncol ; 2023: 9736073, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36824662

RESUMO

In elderly men, prostate cancer is a leading cause of death. Tumor cells require more energy to progress than normal cells, and this energy is mainly dependent on the large amount of ATP support generated by lipid metabolism. Therefore, in this study, we focused on long noncoding RNAs related to lipid metabolism in prostate cancer to discover the biological mechanisms of lipid metabolism regulation. The TCGA-PRAD cohort was used in this study for computational biology analysis. In lipid metabolism biological pathways, 1959 long noncoding RNAs were identified by Pearson correlation coefficient analysis of protein-coding genes, then univariate regression with P values fewer than 0.05. We further identified 784 lncRNAs that were lipid metabolism-related lncRNAs considered to have prognostic value for disease-free survival. Subsequently, we constructed two lncRNA expression patterns of lipid metabolism based on these lncRNAs by nonnegative matrix dimensionality reduction. These two expression patterns showed significant differences in disease-free survival curves for those diagnosed with prostate cancer. We found significant differences in mRNA surveillance pathway and mRNA processing between C1 and C2 groups based on the WGCNA method to explore the biological characteristics of these two expression patterns. Finally, we constructed a disease-free survival (PFS) model based on these lncRNAs. The results identified lncRNAs involved in lipid metabolism and revealed differences in their expression patterns. Additionally, the results offer candidate ideas and approaches concerning the precision treatment of prostate cancer by studying lipid metabolism by candidate long noncoding RNAs.

17.
Int Immunopharmacol ; 116: 109735, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36716517

RESUMO

Three subtypes of samples were generated based on genes involved in fatty acid metabolism in The Cancer Genome Atlas (TCGA)-RCC patients using a non-negative matrix factorization (NMF) algorithm. 32 co-expressed modules were identified using WCGNA. We constructed a four-gene signature in our training set using least absolute shrinkage selection operator regression analysis and verified it in our testing and overall sets. A relevant study analysis in clinical trials was conducted, which showed the model had good stability and potential application value for predicting outcomes. We analyzed the immune microenvironment using MCPcounter, CIBERSORT, quanTIseq, TIMER and ESTIMATE algorithms, and the result indicated risk was positively related to T cells, B-lineage, and fibroblasts and negatively correlated with monocytic lineage, myeloid dendritic cells, neutrophils, and endothelial cells, and CPT1B was positively related to T cells, CD8 + T cells, Cytotoxic lymphocytes and NK cells, and negatively correlated with myeloid dendritic cells, fibroblasts, endothelial cells. Tumor mutation burden was positively related to risk score and the expression of CPT1B using the R packages corrplot, circlize. Through the R package pRRophetic, drug sensitivity tests showed that the low-risk score group would benefit more from sunitinib and less from pazopanib, sorafenib, temsirolimus, gemcitabine and doxorubicin than the high-risk score group. We performed the relevant basic assay validation for CPT1B, and the proliferation ability of RCC cells was inhibited after the knockdown of protein expression of CPT1B. In conclusion, we established a four-gene model that can predict outcomes of RCC with potential applications in diagnosis and treatment.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Prognóstico , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Células Endoteliais , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Ácidos Graxos , Microambiente Tumoral
18.
Langmuir ; 39(5): 2080-2088, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36709440

RESUMO

In this work, a novel two-dimensional (2D) porous nanostructure is constructed upon air/water interfacial assembly of 12-crown-ether-4-incorporated double-decker phthalocyanine (Pc2). The combination of the good electroconductivity of phthalocyanine and the great surface area of the porous structure endows the assembled film with excellent chemical sensing property for ascorbic acid (AA). The low limit of detection can be 0.15 µM with a large linear concentration range and strong anti-interfering ability, which can be comparable to the best results of tetrapyrrole-based electrochemical sensors for AA. Furthermore, the obtained 2D porous assembled film sensor can be applied in real-time monitoring of AA in commercial drinks, indicating its application potential in accurate detection of AA in real samples.

19.
Appl Microbiol Biotechnol ; 107(2-3): 609-622, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36542100

RESUMO

Efficient transporters are necessary for high concentration and purity of desired products during industrial production. In this study, we explored the mechanism of substrate transport and preference of the C4-dicarboxylic acid transporter AoMAE in the fungus Myceliophthora thermophila, and investigated the roles of 18 critical amino acid residues within this process. Among them, the residue Arg78, forming a hydrogen bond network with Arg23, Phe25, Thr74, Leu81, His82, and Glu94 to stabilize the protein conformation, is irreplaceable for the export function of AoMAE. Furthermore, varying the residue at position 100 resulted in changes to the size and shape of the substrate binding pocket, leading to alterations in transport efficiencies of both malic acid and succinic acid. We found that the mutation T100S increased malate production by 68%. Using these insights, we successfully generated an AoMAE variant with mutation T100S and deubiquitination, exhibiting an 81% increase in the selective export activity of malic acid. Simply introducing this version of AoMAE into M. thermophila wild-type strain increased production of malic acid from 1.22 to 54.88 g/L. These findings increase our understanding of the structure-function relationships of organic acid transporters and may accelerate the process of engineering dicarboxylic acid transporters with high efficiency. KEY POINTS: • This is the first systematical analysis of key residues of a malate transporter in fungi. • Protein engineering of AoMAE led to 81% increase of malate export activity. • Arg78 was essential for the normal function of AoMAE in M. thermophila. • Substitution of Thr100 affected export efficiency and substrate selectivity of AoMAE.


Assuntos
Transportadores de Ácidos Dicarboxílicos , Malatos , Malatos/metabolismo , Transportadores de Ácidos Dicarboxílicos/genética , Ácidos Dicarboxílicos/metabolismo
20.
Health Phys ; 124(1): 1-9, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36480580

RESUMO

ABSTRACT: Various low-concentration inert gases, including 222Rn, 133Xe, and 85Kr, pollute the atmosphere near nuclear facilities (e.g., nuclear power plants or reprocessing plants). Owing to the detection limits of instruments, it has become urgent to determine the concentration of these gases efficiently and perform their online monitoring. However, current technologies are limited by low enrichment efficiencies. In this study, a high-pressure, low-flow, large-volume, and high-efficiency adsorption method has been proposed along with a high-temperature, low-pressure, high-flow, and small-volume rapid desorption and collection method, which are based on the gas enrichment principle of activated carbon. The results demonstrated that when dynamic adsorption was implemented using a two-level enrichment method, the final desorbed gas concentration was proportional to the volume ratio of both the large and small activated carbon beds. At a volume ratio of 15:1, 222Rn concentration increased from 110 to 21,016 Bq m-3 after the two-level enrichment; meanwhile, 222Rn concentration increased from 110 to 42,012 Bq m-3 after three-level enrichment. The three-level enrichment technology provides technical support for the enrichment of low-concentration inert gases in the environment, while offering an important technical foundation for improving the monitoring of low-concentration inert gases in specific environments as well as the atmospheric environment.


Assuntos
Carvão Vegetal , Radônio , Radioisótopos de Xenônio
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