A novel molecularly imprinted electrochemical sensor was constructed for the determination of lidocaine, which has a porous and three-dimensional nanostructure. Firstly, dendritic Pt-Pd bimetallic ...nanoparticles (NPs) and porous Pt nano-networks (NWs) were prepared using hexadecylpyridinium chloride as a structure-directing agent. Then, the dendritic Pt-Pd NPs were embedded onto porous Pt NWs and the resultant mixture was coated on a carboxyl graphene modified glassy carbon electrode. Afterwards, the suspension of aminated multi-walled carbon nanotubes loaded with dendritic Pt-Pd NPs was dropped onto the modified electrode surface to reinforce such porous NW and enlarge electrode surface area. Subsequently, a molecularly imprinted polymer film was fabricated by cyclic voltammetry at the modified electrode, using lidocaine as the template and o-phenylenediamine as the monomer. Under optimal conditions, the obtained electrochemical sensor offered an excellent response for lidocaine, the linear response range was from 5.0 10 super(-9) to 4.8 10 super(-6) mol L super(-1) and the detection limit was 1.0 10 super(-10) mol L super(-1). It was successfully applied to the detection of lidocaine in real samples with satisfactory results.
Myocardial ischemia is a condition with insufficient oxygen supporting the heart tissues, which may result from myocardial infarction or trauma-induced hemorrhagic shock. In order to develop better ...preventive and therapeutic strategies for myocardial ischemic damage, it is important that we understand the mechanisms underlying this type of injury. Mitochondrial-derived vesicles (MDVs) have been proposed as a novel player in maintaining mitochondrial quality control. This study aimed to investigate the role and possible mechanisms of MDVs in ischemia/hypoxia-induced myocardial apoptosis. H9C2 cardiomyocytes were used for the cellular experiments. A 40% fixed blood volume hemorrhagic shock rat model was used to construct the acute general ischemic models. MDVs were detected using immunofluorescence staining with PDH and TOM20. Exogenous MDVs were reconstituted
from isolated mitochondria under different hypoxic conditions. The results demonstrate that MDV production was negatively correlated with cardiomyocyte apoptosis under hypoxic conditions; exogenous MDVs inhibited hypoxia-induced cardiomyocyte apoptosis; and MDV-mediated protection against hypoxia-induced cardiomyocyte apoptosis was accomplished via Bcl-2 interactions in the mitochondrial pathway. This study provides evidence that MDVs protect cardiomyocytes against hypoxic damage by inhibiting mitochondrial apoptosis. Our study used a novel approach that expands our understanding of MDVs and highlights that MDVs may be part of the endogenous response to hypoxia designed to mitigate damage. Strategies that stimulate cardiomyocytes to produce cargo-specific MDVs, including Bcl-2 containing MDVs, could theoretically be helpful in treating ischemic/hypoxic myocardial injury.
This study investigated the effects of nisin combined with ε-polylysine on microorganisms and the refrigerated quality of fresh-cut jackfruit. After being treated with distilled water (control), ...nisin (0.5 g/L), ε-polylysine (0.5 g/L), and the combination of nisin (0.1 g/L) and ε-polylysine (0.4 g/L), microporous modified atmosphere packaging (MMAP) was carried out and stored at 10 ± 1°C for 8 days. The microorganisms and physicochemical indexes were measured every 2 days during storage. The results indicated that combined treatment (0.1 g/L nisin, 0.4 g/L ε-polylysine) had the best preservation on fresh-cut jackfruit. Compared with the control, combined treatment inhibited microbial growth (total bacterial count, mold and yeast), reduced the weight loss rate, respiratory intensity, polyphenol oxidase and peroxidase activities, and maintained higher sugar acid content, firmness, and color. Furthermore, it preserved higher levels of antioxidant compounds, reduced the accumulation of malondialdehyde and hydrogen peroxide, thereby reducing oxidative damage and maintaining high nutritional and sensory qualities. As a safe application of natural preservatives, nisin combined with ε-polylysine treatment has great application potential in the fresh-cut jackfruit industry.
Recent studies show that hypoxia can alter expression levels of microRNAs (miRNAs). Whether hypoxia or hemorrhage-induced vascular hyporeactivity is related to miRNAs and the underlying mechanisms of ...this process is not clear. Using hypoxia-treated superior mesenteric arteries (SMAs) and vascular smooth muscle cells (VSMCs) of rats that underwent hemorrhage, we observed the regulatory effects of miR-124/miR-141 on vascular reactivity, the relationship of these miRNAs to RhoA and Rac1, and the mutual regulation of miR-124 and miR-141. The contractile responses of SMAs and VSMCs showed an increase in early stages and a decrease in late stages of hypoxia and hemorrhage. Forty-five miRNAs appeared to have been significantly changed in SMAs after hypoxia, and miR-124 and miR-141 underwent the most change. Overexpressed miR-124 or miR-141 and their antisenses appeared to alter both vascular reactivity and expression of the proteins RhoA and Rac1 after hypoxia. miR-124 inhibited Rac1 by acting at the Rac1 mRNA 3'-untranslated region (UTR), but it led to an increase in RhoA by inhibiting miR-141. miR-141 inhibited RhoA by acting at the RhoA mRNA 3'-UTR, but it led to an increase in Rac1 by inhibiting miR-124. Further study found that miR-124 inhibited miR-141 via transcription factor early growth response gene-1 (Egr-1), whereas miR-141 inhibited miR-124 via transcription of nuclear factor erythroid 2-related factor 2 (Nrf-2). These results suggest that miR-124 and miR-141 participate in the regulation of vascular reactivity after hypoxia and hemorrhage by regulating expression of the RhoA and Rac1 proteins, and in doing so, miR-124 and miR-141 are mutually regulated. These findings provide potential targets for restoring vascular function as part of the treatment protocol for hemorrhagic shock and some other critical illness.
This article investigates multi-attribute group decision-making (MAGDM) problems based on interval-valued Pythagorean fuzzy linguistic sets (IVPFLSs). The IVPFLSs are regarded as an efficient tool to ...describe decision makers' (DMs') evaluation information from both quantitative and qualitative aspects. However, existing IVPFLSs based MAGDM methods are still insufficient and inadequate to deal with complicated practical situations. This article aims to propose a novel MAGDM method and the main contributions of the present work are three-fold. First, we propose new operations of interval-valued Pythagorean fuzzy linguistic numbers (IVPFLNs) based on linguistic scale function. Second, we propose new aggregation operators (AOs) of IVPFLNs based on power average operator and Muirhead mean. The proposed AOs take the interrelationship among any numbers of attributes into account and eliminate the bad influence of DMs' unreasonable evaluation values on the final decision results. Third, based on the new operations and AOs of IVPFLNs, we introduce a novel approach to MAGDM and present its main steps. Finally, we discuss the effectiveness of the proposed approach and investigates their advantages through numerical examples.
In this study, we developed an evaluation index system for green total-factor water-use efficiency (GTFWUE) which reflected both economic and green efficiencies of water resource utilization. Then we ...measured the GTFWUE of 30 provinces/municipalities/autonomous regions (hereafter provinces) in China (not including Tibet, Hong Kong, Macao, Taiwan as no data) from 2000 to 2018 using a minimum distance to the strong frontier model that contained an undesirable output. We further analyzed the regional differences and spatial correlations of GTFWUE using these values based on Global and Local Moran’s
I
statistics, and empirically determined the factors affecting GTFWUE using a spatial econometric model. The evaluation results revealed that the GTFWUE differed substantially between the regions. The provinces with high and low GTFWUE values were located in the coastal and inland areas of China, respectively. The eastern region had a significantly higher GTFWUE than the central and western regions. The GTFWUEs for all three regions (eastern, central, and western regions) decreased slowly from 2000 to 2011 (except 2005), remained stable from 2012 to 2016, and rapidly increased in 2017 before decreasing again in 2018. We found significant spatial correlations between the provincial GTFWUEs. The GTFWUE for most provinces belonged to the high-high or low-low cluster region, revealing a significant spatial clustering effect of provincial GTFWUEs. We also found that China’s GTFWUE was highly promoted by economic growth, population size, opening-up level, and urbanization level, and was evidently hindered by water endowment, technological progress, and government influence. However, the water-use structure had little impact on GTFWUE. This study fully demonstrated that the water use mode would be improved, and water resources needed to be used more efficiently and green in China. Moreover, based on the findings of this study, several policy recommendations were proposed from the aspects of cross-regional cooperation, economy, society, and institution.
Due to the high energy density, mature production technology, ease of storage and transportation, and the no carbon/sulfur nature of ammonia fuel, direct-ammonia solid oxide fuel cells (DA-SOFCs) ...have received rapidly increasing attention, showing distinct advantages over H2-fueled SOFCs and low-temperature fuel cells. However, DA-SOFCs with conventional Ni-based cermet anodes still suffer from several drawbacks, including serious sintering and inferior activity for ammonia decomposition, strongly limiting the large-scale applications. To tackle the above-mentioned issues, exsolved NiCo nanoparticles decorated double perovskite oxides are fabricated and employed as high-performance anodes for DA-SOFCs in this work. By optimizing the Ni doping amount in Sr2CoMo1−xNixO6−δ (x = 0.1, 0.2 and 0.3), the reduced Sr2CoMo0.8Ni0.2O6−δ (r-SCMN2) anode exhibits superb catalytic activity for ammonia cracking reaction and high anti-sintering capability. More specifically, the electrolyte-supported single cell with r-SCMN2 nanocomposite anode delivers superior power outputs and operational durability in ammonia fuel as compared with other r-SCMN anodes owing to the significantly promoted nanoparticle exsolution and stronger interaction between alloy nanoparticles and the support. In summary, this study presents an effective strategy for the design of efficient and stable nanocomposite anodes for DA-SOFCs.
The entomopathogenic fungus
strain MJ1015, recently isolated from white grubs on a blueberry farm in Guizhou, China, could be used as a biocontrol agent. As a first step toward determining the effect ...of different solid culture media, temperature, and pH on colony growth rate and sporulation, we evaluated the optimum solid medium for mycelial growth and conidia production on a commercial scale. Subsequently, we also used single-factor analysis and response surface optimization to optimize the composition of the solid culture medium. On potato dextrose agar (PDA) medium, MJ1015 grew fastest and produced the highest spore yield at 29°C and pH 5. The best solid medium for the growth and sporulation of strain MJ1015 comprised 64.70 g/l of rice, 13.00 g/l of wheat, 0.30 g/l of NaNO
, 0.36 g/l of K
HPO
· 3H
O, and 1.00 g/l of CaCO
. Rice, NaNO
, and K
HPO
· 3H
O were the main influencing factors. The predicted value of cultured spores using the optimal medium was 4.56 x 10
conidia/l. The validation test results showed that the average growth rate of strain MJ1015 on the optimal medium was 85% and 96% faster than that on Sabouraud dextrose agar with yeast extracts medium (SDAY) and PDA, respectively. Sporulation was 43.90 times and 9.65 times of that produced on SDAY and PDA, respectively. Our findings provide a theoretical basis for the commercial production of
to control white grubs.
Due to their beneficial effects on human health, antioxidant peptides have attracted much attention from researchers. However, the structure-activity relationships of antioxidant peptides have not ...been fully understood. In this paper, quantitative structure-activity relationships (QSAR) models were built on two datasets, i.e., the ferric thiocyanate (FTC) dataset and ferric-reducing antioxidant power (FRAP) dataset, containing 214 and 172 unique antioxidant tripeptides, respectively. Sixteen amino acid descriptors were used and model population analysis (MPA) was then applied to improve the QSAR models for better prediction performance. The results showed that, by applying MPA, the cross-validated coefficient of determination (Q²) was increased from 0.6170 to 0.7471 for the FTC dataset and from 0.4878 to 0.6088 for the FRAP dataset, respectively. These findings indicate that the integration of different amino acid descriptors provide additional information for model building and MPA can efficiently extract the information for better prediction performance.
In this paper, the optimal ratio of tannic acid (TA) and sodium molybdate (SM) and the influence of different hydrodynamic factors on the corrosion inhibition effect of 304 stainless steel at 90° ...bending were evaluated. This study combines static immersion and simulation of a pipeline circulating flow device, and uses electrochemical and computational fluid dynamics (CFD) simulations to evaluate the corrosion inhibition effect of corrosion inhibitors in this system. The optimal ratio of tannic acid and sodium molybdate is 3 g/L tannic acid +0.05 g/L sodium molybdate. The study found that the corrosion inhibition efficiency of the corrosion inhibitor at different positions of the elbow is different, and the corrosion inhibition efficiency decreases with the increase of the flow rate. The surface morphology and corrosion products of the samples were analyzed by SEM and XPS, which further verified the experimental results and analyzed the corrosion inhibition mechanism.
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