Guaiacol (2-methoxyphenol) has a high emission rate from wood burning and mainly exists in the gas phase, but the formation potential of secondary organic aerosol (SOA) from the atmospheric oxidation ...of guaiacol has not been well determined yet. In this work, SOA formation from the gas-phase reaction of guaiacol with OH radicals was investigated using an oxidation flow reactor (OFR) under different experimental conditions. The results showed that SOA yield was dependent on guaiacol concentration, OH exposure, and the presence of SO2 and NO2. SOA yield firstly increased and then decreased as a function of OH exposure. The maximum SOA yield (0.28–0.54) obtained at different guaiacol concentrations could be well-expressed by a one-product model. The SOA oxidation degree was represented by the carbon oxidation state (OSC) and f44/f43 (the ratio of organic mass fractions of m/z 44 to m/z 43), which both increased linearly and significantly with the increase of OH exposure. In addition, SO2 and NO2 promoted SOA formation, for which the maximum yield enhancements were 13.38% and 10.69%, respectively. The N/C ratio (0.034–0.045) indicated that NO2 participated in the OH-initiated reaction of guaiacol, consequently resulting in the formation of organic nitrates. The experimental results would be helpful to further the understanding of SOA formation from the atmospheric oxidation of guaiacol and its subsequent impacts on air quality and climate.
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•Significant SOA formation from OH-oxidation of guaiacol in the OFR was observed.•SOA yield was dependent on guaiacol concentration and OH exposure.•OSC and f44/f43 ratio of SOA both increased significantly with OH exposure raising.•The presence of SO2 and NO2 enhanced SOA formation.•NO2 participated in the OH-initiated reaction and then produced organic nitrates.
Polymeric immunoglobulin receptor (pIgR), the transmembrane transporter of polymeric immunoglobulin A and M, has multiple immune functions. To explore the characteristics of pIgR expression in ...Bactrian camel lungs, twelve healthy adult (2-7 years old) Bactrian camels were systematically studied. The results showed that pIgR was mainly expressed in the cytoplasm and membrane of ciliated cells, as well as in the cytoplasm and membrane of basal cells, serous cells of bronchial glands, club cells and alveolar type 2 cells in Bactrian camel lungs. Specially, as the bronchial branches extended, the pIgR expression level in ciliated cells significantly declined (p<0.05), and the corresponding bronchial luminal areas obviously decreased (p<0.05). However, pIgR was not expressed in goblet cells, endocrine cells, alveolar type 1 cells and mucous cells of bronchial glands. The results demonstrated that ciliated cells continuously distributed throughout the whole bronchial tree mucosa were the major expression sites of pIgR, and pIgR was also expressed in basal cells, serous cells of bronchial glands, club cells and alveolar type 2 cells, which would facilitate secretory immunoglobulin A (SIgA) transmembrane transport by pIgR and form an intact protective barrier. Moreover, the pIgR expression level in ciliated cells was positively correlated with the bronchial luminal areas; but negatively correlated with the cleanliness of airflow through the bronchial cross-sections, showing that the pIgR expression level in the bronchial epithelium was inhomogeneous. Our study provided a foundation for further exploring the regulatory functions of immunoglobulins (i.e., SIgA) after transport across the membrane by pIgR in Bactrian camel lungs.
Objective
To examine the expression levels of the glycosyltransferase 8 domain containing protein 2 and its clinical implications in urothelial carcinoma patients.
Methods
Data mining, ...immunohistochemistry together with H‐score calculation was carried out to evaluate the glycosyltransferase 8 domain containing protein 2 levels on tissue specimens from urothelial carcinoma patients, retrospectively. Correlations between glycosyltransferase 8 domain containing protein 2 H‐score and imperative clinicopathological factors were measured. The indication of glycosyltransferase 8 domain containing protein 2 level on disease‐specific and metastasis‐free survivals were next analyzed.
Results
In upper tract urothelial carcinomas (n = 340) and bladder urothelial carcinomas (n = 295), 170 (50%) and 148 (50%) patients, respectively, were identified to have high glycosyltransferase 8 domain containing protein 2 expression. The glycosyltransferase 8 domain containing protein 2 levels were correlated to several clinicopathological characteristics and patient survival. Upregulation of the glycosyltransferase 8 domain containing protein 2 was correlated to primary tumor (P < 0.001), nodal metastasis (P < 0.001), histological grade (P < 0.001), vascular invasion (P < 0.001), perineural invasion (P < 0.05) and mitotic rate (P < 0.001). High glycosyltransferase 8 domain containing protein 2 levels independently predicted poor disease‐specific survival (P = 0.049) and metastasis‐free survival (P = 0.008) in upper tract urothelial carcinoma and urinary bladder urothelial carcinoma, respectively. Gene Ontology enrichment analysis additionally showed that multiple biological processes were enriched including “ECM organization” (Gene Ontology:0030198), “extracellular structure organization” (Gene Ontology:0043062), “biological adhesion” (Gene Ontology:0022610), “cell adhesion” (Gene Ontology:0007155), “collagen fibril organization” (Gene Ontology:0030199) and “vasculature development” (Gene Ontology:0001944).
Conclusions
The present findings suggest that upregulation of the glycosyltransferase 8 domain containing protein 2 is an independent and disadvantageous prognosticator in urothelial carcinoma. High glycosyltransferase 8 domain containing protein 2 level might play a crucial role in progression of urothelial carcinoma.
Ag-based catalysts with different supports (TiO2, Al2O3 and CeO2) were prepared by impregnation method and subsequently tested for the catalytic oxidation of formaldehyde (HCHO) at low temperature. ...The Ag/TiO2 catalyst showed the distinctive catalytic performance, achieving the complete HCHO conversion at around 95 °C. In contrast, the Ag/Al2O3 and Ag/CeO2 catalysts displayed much lower activity and the 100% conversion was reached at 110 °C and higher than 125 °C, respectively. The Ag-based catalysts were next characterized by several methods. The characterization results revealed that supports have the dramatic influence on the Ag particle sizes and dispersion. Kinetic tests showed that the Ag based catalyst on the TiO2, Al2O3 or CeO2 supports have the similar apparent activation energy of 65 kJ mol(-1), indicating that the catalytic mechanism keep immutability over these three catalysts. Therefore, Ag particle size and dispersion was confirmed to be the main factor affecting the catalytic performance for HCHO oxidation. The Ag/TiO2 catalyst has the highest Ag dispersion and the smallest Ag particle size, accordingly presenting the best catalytic performance for HCHO oxidation.
Measuring high energy cosmic ray electrons/positrons (CRE) provides important means for the dark matter (DM) indirect detection and for probing the nearby galactic sources. In this work, we perform a ...systematic analysis of the flavor structure of DM annihilations into charged leptons based on the cosmic ray CRE spectra measured by DAMPE, Fermi-LAT, AMS-02, and CALET experiments. We study the annihilations of possible TeV scale DM particles in a nearby subhalo, which is proposed to explain the possible peak-like structure of the DAMPE CRE data. We pay special attention to the possible non-resonant excess (besides the possible peak-like structure) and demonstrate that such non-resonant excess can mainly arise from the decay of muons produced by the DM annihilations in the subhalo. With these we study the flavor composition of the lepton final states from DM annihilations χχ→e+e−,μ+μ−,τ+τ− by fitting the CRE data. We demonstrate that decays of the final states μ+μ− and τ+τ− can provide the non-resonant excess, while the peak excess arises from the e+e− final state. We further analyze the constraints on the lepton flavor composition using the Fermi-LAT γ-ray measurements. We find that the flavor composition is consistent with the Fermi-LAT data at relatively low Galactic latitudes, while the fraction of the final state τ± is severely bounded.
The improvement of treatment for patients with ‘driver‐gene‐negative’ lung adenocarcinoma (LUAD) remains a critical problem to be solved. We aimed to explore the role of methylation of N6 adenosine ...(m6A)‐related long noncoding RNA (lncRNA) in stratifying ‘driver‐gene‐negative’ LUAD risk. Patients negative for mutations in EGFR, KRAS, BRAF, HER2, MET, ALK, RET, and ROS1 were identified as ‘driver‐gene‐negative’ cases. RNA sequencing was performed in 46 paired tumors and adjacent normal tissues from patients with ‘driver‐gene‐negative’ LUAD. Twenty‐three m6A regulators and relevant lncRNAs were identified using Pearson's correlation analysis. K‐means cluster analysis was used to stratify patients, and a prognostic nomogram was developed. The CIBERSORT and pRRophetic algorithms were employed to quantify the immune microenvironment and chemosensitivity. We identified two clusters highly consistent with the prognosis based on their unique expression profiles for 46 m6AlncRNAs. A risk model constructed from nine m6A lncRNAs could stratify patients into high‐ and low‐risk groups with promising predictive power (C‐index = 0.824), and the risk score was an independent prognostic factor. The clusters and risk models were closely related to immune characteristics and chemosensitivity. Additional pan‐cancer analysis using the nine m6AlncRNAs showed that the expression of DIO3 opposite strand upstream RNA (DIO3OS) is closely related to the immune/stromal score and tumor stemness in a variety of cancers. Our results show that m6AlncRNAs are a reliable prognostic tool and can aid treatment decision‐making in ‘driver‐gene‐negative’ LUAD. DIO3OS is associated with the development of various cancers and has potential clinical applications.
Based on RNA sequencing results for patients with ‘driver‐gene‐negative’ lung adenocarcinoma (LUAD), m6A‐related lncRNAs were found and experimentally verified to have good predictive efficacy for the prognosis and immune characteristics of patients with ‘driver‐gene‐negative’ LUAD. DIO3OS as a key lncRNA was found to affect tumor cell stemness in a variety of cancers.
Objective: To determine whether exoskeleton-assisted walking (EAW) improves pulmonary ventilation function, motor function and related body structure, and activities equivalently as the conventional ...exercise program for people with spinal cord injury (SCI). Methods: Forty participants (7 females and 33 males; age 37.1±12.0 years) with thoracic SCI were randomized into two groups and undertook 16 sessions of 50-60 min training (4 days/week). Participants in the EAW group received EAW trainings, such as assisted standing, walking, and climbing the stairs. The control group received a conventional exercise program. Outcomes were measured at baseline and upon completion of treatment. Results: After trainings, the EAW group improved more than the control group in the forced vital capacity (FVC, 0.53 L 0.01-1.06 L), predicted FVC% (19.59 6.63-32.54) and forced expiratory volume in 1s (0.61 L 0.15-1.07 L), basic activities of daily living (BADL) (19.75 10.88-28.62), and distal femoral cartilage. Participants in the EAW group completed 6-minute walk test with median 17.3 meters while wearing the exoskeleton. There was no difference in trunk and lower extremity motor function, bone mineral density, and adverse events (<inline-formula> <tex-math notation="LaTeX">{P} </tex-math></inline-formula> > 0.05). Conclusion: In people with lower thoracic neurological level of SCI, EAW training has potential benefits to facilitate pulmonary ventilation function, walking, BADL and thickness of cartilage comparing to a conventional excise program. Significance: This study provided more evidence for using EAW in clinic, and partly proved EAW had equivalent effects as conventional exercise program, which may combine with conventional exercise program for reducing burden of therapists in the future.
Summary
The bacterial cell envelope is critical to support and maintain cellular life. In Gram‐negative bacterial cells, the outer membrane and the peptidoglycan layer are two important parts of the ...cell envelope and they harbour abundant proteins. Here, we report the identification and characterization of a previously unknown peptidoglycan‐associated protein, PapA, from the Gram‐negative Comamonas testosteroni. PapA bound peptidoglycan with its C‐terminal domain and interacted with the outer‐membrane porin OmpC. The PapA‐OmpC complex riveted the outer membrane and the peptidoglycan layer, and played a role in maintaining cell envelope integrity. When papA was disrupted, the mutant CNB‐1ΔpapA apparently had an outer membrane partly separated from the peptidoglycan layer. Phenotypically, the mutant CNB‐1ΔpapA lost chemotactic responses and had longer lag‐phase of growth, less flagellation and higher sensitivity to harsh environments. Totally, 1093 functionally unknown PapA homologues were identified from the public NR protein database and they were mainly distributed in Burkholderiales of Betaproteobacteria. Our finding provides a clue that the PapA homologous proteins might function as a rivet to maintain cell envelope integrity in those Gram‐negative bacteria.
Increasing sulfate input has been seen as an issue in management of aquatic ecosystems, but its influences on eutrophic freshwater lakes is not clear. In this study, it was observed that increasing ...sulfate concentration without additional cyanobacterial bloom biomass (CBB) addition did not have an obvious effect on element cycling during 1-year continuous flow mesocosm experiments in which water and sediments were taken from a shallow eutrophic lake with sulfate levels near 1 mM. However, following addition of CBB to mesocosms, sulfate-reducing bacteria (SRB) were observed in the water column, and increasing numbers of SRB in the water column were associated with higher sulfate input. Sulfate amendment (0–70 mg L−1) also resulted in a larger amount of total dissolved sulfide (peak values of 5.90 ± 0.36 to 7.60 ± 0.12 mg L−1) in the water column and acid volatile sulfide (1081.71 ± 69.91 to 1557.98 ± 41.72 mg kg−1) in 0–1 cm surface sediments due to sulfate reduction. During the period of CBB decomposition, increasing sulfate levels in the water column were positively correlated with increasing diffusive phosphate fluxes of 1.23 ± 0.32 to 2.17 ± 0.01 mg m−2 d−1 at the water-sediment interface. As increases in sulfide and phosphate release rates deteriorated the water quality/ecosystem and even spurred the occurrence of a black water problem in lakes, the control of sulfate input level should be considered for shallow eutrophic lake management, especially during cyanobacterial bloom periods.
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•Algae decay induced sulfate reduction in water column of shallow lake mesocosms.•Greater sulfide levels were linked to higher sulfate input during algae decay.•High sulfate promoted P release from sediments during algae degradation.•Enhanced sulfate reduction may promote black water formation in freshwater lakes.•Control of sulfate input needs consideration for eutrophic shallow lake management.
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