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•Groundwater chemistry and quality were analyzed in the Ningxia region.•NO3−, NH4+ and NO2− are related to human pollution.•Water quality was assessed using an integrated weight ...matter-element extension model.•High health risks of F−, NO3−, NH4+, and NO2− were found, especially for children.
Assessing groundwater quality and identifying pollutant risks are essential for managing groundwater resources in arid and semi-arid regions. An analysis of the hydrochemical characteristics, controlling factors, and pollutant characteristics of the groundwater in the upper Yellow River region is presented to understand the overall groundwater quality and identify the risk to human health in this region. Traditional hydrochemical analysis methods, integrated weight matter-element extension analysis, and health risk models were used in this study. A total of 210 groundwater samples were collected from the wells for physical and chemical analyses. Results showed that groundwater in the study area was weakly alkaline, with the predominant hydrochemical types of groundwater being SO4·Cl-Ca·Mg, SO4·Cl-Na, and HCO3-Ca·Mg. The hydrochemical composition of the groundwater is controlled by rock dominance, evaporation dominance, and cation exchange. Nitrogen pollution of groundwater is caused by industrial activities and fertilizers; fluorine pollution is caused by fluorite dissolution. To reasonably evaluate the groundwater quality, the groundwater evaluation method based on an integrated weight matter-element extension analysis was optimized. The method effectively avoids defects of G1 and entropy weight methods in determining weights and thoroughly considers the fuzziness and uncertainty of the water quality grade. The overall quality groundwater assessment results showed that 96.19% of the overall water quality in the study area was good and could be used in many ways. Land irrigated with groundwater is mainly exposed to salinity hazards. Health risk assessment results showed that 57% and 21% of the samples posed unacceptable health risks to children and adults, respectively. Therefore, more attention should be paid to real-time, continual monitoring of pollutants in groundwater management. The results help decision makers make wise decisions on identifying groundwater purposes to avoid further water quality deterioration and increase in pollutants, ensuring the cleanliness of groundwater resources in the upper Yellow River..
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•We report a cheaper yet higher efficient HER electrocatalyst than Pt.•The Ru@2D-NC is synthesized though a simple organic/aqueous interfacial strategy.•It exhibits low η@10 of 31 and ...29 mV in alkaline and acidic media respectively.•Optimized ΔG(H*) and ΔGB(H2O) are obtained via interatomic charge redistribution.•The strong Ru-support interaction endows the catalyst with excellent durability.
The development of efficient and durable electrocatalysts for hydrogen evolution reaction (HER) is crucial for sustainable electrochemical water splitting and its practical application. However, the inappropriate binding with H* and sluggish reaction kinetics limit their overall HER performance, especially in alkaline electrolyte. Herein, we report a robust and high active HER electrocatalyst with optimized metal-H* interaction and low water dissociation energy barrier through interatomic d-p orbital hybridization. The Ru nanoparticles with mean size down to 1.7 nm are anchored on two-dimension nitrogen-doped carbon nanocone arrays via a facile aqueous-organic interfacial method. This unique architecture induces strong interaction between Ru and the carbon support. Electrons are transferred from Ru to the N-doped carbon, causing a shift of charge distribution and modified surface properties of Ru. Furthermore, the newly emerged Ru-N bonds endow the catalyst with high structure robustness. As a result, the catalyst exhibits superior HER performances in both alkaline and acidic electrolytes, with low overpotentials (31 and 29 mV at 10 mA cm−2 respectively), high H2 turn over frequency (2.20 s−1 at the overpotential of 25 mV) and excellent durability (10,000 cycles). The density functional theory calculations reveal that the boosted HER activity can be attributed to the downshift of the d-band center of Ru, which lowers the |ΔG(H*)| and accelerates the H-OH cleavage.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In cognitive radio (CR), the detection performance of traditional spectrum sensing may be decreased due to the multipath fading and shadowing effect. However, unmanned aerial vehicle (UAV) can ...receive a higher strength signal without suffering severe fading and shadowing. In this paper, an UAV-based CR is proposed to improve spectrum sensing performance and access the idle spectrum. The UAV performs circular flight with the PU locating at the center, and the flight period is divided into sensing radian and transmission radian. Only when the absence of the PU has been detected within sensing radian can the UAV access the spectrum. The spectrum sensing optimization is formulated as an optimization problem, which seeks to maximize the effective throughput of the UAV by optimizing the sensing radian subject to the constraint of the interference throughput. Then, virtual cooperative spectrum sensing is proposed to improve sensing performance in fading channel, and the effective throughput is maximized by jointly optimizing local sensing radian and the number of sensing slots. The simulation results show that better UAV transmission performance can be obtained by optimizing spectrum sensing, and the virtual cooperative spectrum sensing outperforms the single spectrum sensing especially in deep fading channel.
Extant literature has suggested that leadership styles have a significant impact on subordinate taking charge. However, the effect of ethical leadership on subordinate taking charge is still ...insufficiently explored. Drawing on social exchange theory, we developed a moderated mediation model in which social exchange was theorized as a mediating mechanism underlining why subordinates feel motivated to take charge with the supervision of ethical leadership. Moreover, power distance was supposed to be a relevant boundary condition to moderate such a relationship. Two hundred thirty-nine independent leader-subordinate dyads in China were used to test the model. Results showed that subordinates' social exchange mediates the relationship between ethical leadership and subordinate taking charge, and such a relationship was found to be stronger among subordinates who had lower levels of power distance rather than higher levels. Theoretical and practical implications concerning enhancement of subordinate taking charge in organizations where ethical leaderships exist are discussed.
To investigate the trends and correlation between antibacterial consumption and carbapenem resistance in Gram-negative bacteria from 2012 to 2019 in a tertiary-care teaching hospital in southern ...China.
This retrospective study included data from hospital-wide inpatients collected between January 2012 and December 2019. Data on antibacterial consumption were expressed as defined daily doses (DDDs)/1000 patient-days. Antibacterials were classified according to the Anatomical Therapeutic Chemical (ATC) classification system. The trends in antimicrobial usage and resistance were analyzed by linear regression, while Pearson correlation analysis was used for assessing correlations.
An increasing trend in the annual consumption of tetracyclines, β-lactam/β-lactamase inhibitor (BL/BLI) combinations, and carbapenems was observed (P < 0.05). Carbapenem resistance in Acinetobacter baumannii (A. baumannii) significantly increased (P < 0.05) from 18% in 2012 to 60% in 2019. Moreover, significant positive correlations were found between resistance to carbapenems in A. baumannii (P < 0.05) and Escherichia coli (E. coli; P < 0.05) and consumption of carbapenems, while the resistance rate of A. baumannii to carbapenems was positively correlated with cephalosporin/β-lactamase inhibitor (C/BLI) combinations (P < 0.01) and tetracyclines usage (P < 0.05). We also found that use of quinolones was positively correlated with the resistance rate of Burkholderia cepacia (B. cepacia) to carbapenems (P < 0.05), and increasing uses of carbapenems (P < 0.01) and penicillin/β-Lactamase inhibitor (P/BLI) combinations (P < 0.01) were significantly correlated with reduced resistance of Enterobacter cloacae (E. cloacae) to carbapenems.
These results revealed significant correlations between consumption of antibiotics and carbapenem resistance rates in Gram-negative bacteria. Implementing proper management strategies and reducing the unreasonable use of antibacterial drugs may be an effective measure to reduce the spread of carbapenem-resistant Gram-negative bacteria (CRGN), which should be confirmed by further studies.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Development of personalized cancer vaccines based on neoantigens has become a new direction in cancer immunotherapy. Two forms of cancer vaccines have been widely studied: tumor-associated antigen ...(including proteins, peptides, or tumor lysates)-pulsed dendritic cell (DC) vaccines and protein- or peptide-adjuvant vaccines. However, different immune modalities may produce different therapeutic effects and immune responses when the same antigen is used. Therefore, it is necessary to choose a more effective neoantigen vaccination method. In this study, we compared the differences in immune and anti-tumor effects between neoantigen-pulsed DC vaccines and neoantigen-adjuvant vaccines using murine lung carcinoma (LL2) candidate neoantigens. The enzyme-linked immunospot (ELISPOT) assay showed that 4/6 of the neoantigen-adjuvant vaccines and 6/6 of the neoantigen-pulsed DC vaccines induced strong T-cell immune responses. Also, 2/6 of the neoantigen-adjuvant vaccines and 5/6 of the neoantigen-pulsed DC vaccines exhibited potent anti-tumor effects. The results indicated that the neoantigen-pulsed DC vaccines were superior to the neoantigen-adjuvant vaccines in both activating immune responses and inhibiting tumor growth. Our fundings provide an experimental basis for the selection of immune modalities for the use of neoantigens in individualized tumor immunotherapies.
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EMUNI, FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract
Background
Pleural effusion (PE) can be divided into benign pleural effusion (BPE) and malignant pleural effusion (MPE). There is no consensus on the identification of lung cancer-associated ...MPE using the optimal cut-off levels from five common tumor biomarkers (CEA, CYFRA 21-1, CA125, SCC-Ag, and NSE). Therefore, we aimed to find indicators for the auxiliary diagnosis of lung cancer-associated MPE by analyzing and then validating the optimal threshold levels of these biomarkers in pleural fluid (PF) and serum, as well as the PF/serum ratio.
Patients and method
The study has two sets of patients, i.e. the training set and the test set. In the training set, 348 patients with PE, between January 1, 2016 and December 31, 2017, were divided into BPE and MPE based on the cytological diagnosis. Subsequently, the optimal cut-off levels of tumor biomarkers were analyzed. In the test set, the diagnostic compliance rate was verified with 271 patients with PE from January 1, 2018 to July 31, 2019 to evaluate the auxiliary diagnostic value of the aforementioned indicators.
Result
In the training set, PF CEA at the cut-off value of 5.23 ng/ml was the most effective indicator for MPE compared with other tumor biomarkers (all
p
< 0.001). In the test set, PF CEA at the cut-off value of 5.23 ng/ml showed the highest sensitivity, specificity and accuracy, positive and negative predictive value among other tumor biomarkers, which were 99.0%, 69.1%, 91.6%, 90.7%, and 95.9%, respectively.
Conclusion
PF CEA at the cut-off level of 5.23 ng/ml was the most effective indicator for identifying lung cancer-associated MPE among the five common tumor biomarkers.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The Polar Regions (PRs) are characterized by ice sheets, sea ice, glaciers, tundra, and other cryospheric landscapes and associated aboriginal cultural features. This primitive polar landscape is a ...huge contrast to the current human living environment and is a strong tourist attraction. Rapid environmental changes and the emergence of conflicts between tourism development and ecological protection, have affected sustainable development of polar tourism (PT). Polar high-latitude characteristics determine the vulnerability of their environment and the higher sensitivity of PT to climate change. This study comprehensively analyzed the status quo of PT development, systematically revealed mutual influence between environmental changes and tourism development, and proposed some adaptive measures to coordinate environment protection and tourism development.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Owing to their broad-spectrum antibacterial properties, multitarget effects, and low drug resistance, antimicrobial peptides (AMPs) have played critical roles in the clinical therapy of ...drug-resistant bacterial infections. However, the potential hazard of hemolysis following systemic administration has greatly limited their application. Here, we developed a novel AMP derivative, DP7-C, by modifying a formerly identified highly active AMP (DP7) with cholesterol to form an amphiphilic conjugate. The prepared DP7-C easily self-assembled into stable nanomicelles in aqueous solution. The DP7-C micelles showed lower hemolytic activity than their unconjugated counterparts toward human red blood cells and a maximum tolerated dose of 80 mg/kg of body weight in mice via intravenous injection, thus demonstrating improved safety. Moreover, by eliciting specific immunomodulatory activities in immune cells, the DP7-C micelles exerted distinct therapeutic effects in zebrafish and mouse models of infection. In conclusion, DP7-C micelles may be an excellent candidate for the treatment of bacterial infections in the clinic.
H2 has shown anti-inflammatory and antioxidant ability in many clinical trials, and its application is recommended in the latest Chinese novel coronavirus pneumonia (NCP) treatment guidelines. ...Clinical experiments have revealed the surprising finding that H2 gas may protect the lungs and extrapulmonary organs from pathological stimuli in NCP patients. The potential mechanisms underlying the action of H2 gas are not clear. H2 gas may regulate the anti-inflammatory and antioxidant activity, mitochondrial energy metabolism, endoplasmic reticulum stress, the immune system, and cell death (apoptosis, autophagy, pyroptosis, ferroptosis, and circadian clock, among others) and has therapeutic potential for many systemic diseases. This paper reviews the basic research and the latest clinical applications of H2 gas in multiorgan system diseases to establish strategies for the clinical treatment for various diseases.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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