788 research outputs found

    Quantitative electron energy-loss spectroscopy (EELS) analyses of lead zirconate titanate

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    Electron energy-loss spectroscopy (EELS) analyses have been performed on a sol–gel deposited lead zirconate titanate film, showing that EELS can be used for heavy as well as light element analysis. The elemental distributions within the sol–gel layers are profiled using the Pb N<sub>6,7</sub>-edges, Zr M-edges, Ti L-edges and O K-edge. A multiple linear least squares fitting procedure was used to extract the Zr signal which overlaps with the Pb signal. Excellent qualitative information has been obtained on the distribution of the four elements. The non-uniform and complementary distributions of Ti and Zr within each sol–gel deposited layer are observed. The metal:oxygen elemental ratios are quantified using experimental standards of PbTiO<sub>3</sub>, PbZrO<sub>3</sub>, ZrO<sub>2</sub> and TiO<sub>2</sub> to provide relevant cross-section ratios. The quantitative results obtained for Ti/O and Pb/O are very good but the Zr/O results are less accurate. Methods of further improving the results are discussed

    Identification of the Metabolic Enzyme Involved Morusin Metabolism and Characterization of Its Metabolites by Ultraperformance Liquid Chromatogaphy Quadrupole Time-of-Flight Mass Spectrometry (UPLC/Q-TOF-MS/MS)

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    Morusin, the important active component of a traditional Chinese medicine, Morus alba L., has been shown to exhibit many vital pharmacological activities. In this study, six recombinant CYP450 supersomes and liver microsomes were used to perform metabolic studies. Chemical inhibition studies and screening assays with recombinant human cytochrome P450s were also used to characterize the CYP450 isoforms involved in morusin metabolism. The morusin metabolites identified varied greatly among different species. Eight metabolites of morusin were detected in the liver microsomes from pigs (PLMs), rats (RLMs), and monkeys (MLMs) by LC-MS/MS and six metabolites were detected in the liver microsomes from humans (HLMs), rabbits (RAMs), and dogs (DLMs). Four metabolites (M1, M2, M5, and M7) were found in all species and hydroxylation was the major metabolic transformation. CYP1A2, CYP2C9, CYP2D6, CYP2E1, CYP3A4, and CYP2C19 contributed differently to the metabolism of morusin. Compared to other CYP450 isoforms, CYP3A4 played the most significant role in the metabolism of morusin in human liver microsomes. These results are significant to better understand the metabolic behaviors of morusin among various species

    HVDetFusion: A Simple and Robust Camera-Radar Fusion Framework

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    In the field of autonomous driving, 3D object detection is a very important perception module. Although the current SOTA algorithm combines Camera and Lidar sensors, limited by the high price of Lidar, the current mainstream landing schemes are pure Camera sensors or Camera+Radar sensors. In this study, we propose a new detection algorithm called HVDetFusion, which is a multi-modal detection algorithm that not only supports pure camera data as input for detection, but also can perform fusion input of radar data and camera data. The camera stream does not depend on the input of Radar data, thus addressing the downside of previous methods. In the pure camera stream, we modify the framework of Bevdet4D for better perception and more efficient inference, and this stream has the whole 3D detection output. Further, to incorporate the benefits of Radar signals, we use the prior information of different object positions to filter the false positive information of the original radar data, according to the positioning information and radial velocity information recorded by the radar sensors to supplement and fuse the BEV features generated by the original camera data, and the effect is further improved in the process of fusion training. Finally, HVDetFusion achieves the new state-of-the-art 67.4\% NDS on the challenging nuScenes test set among all camera-radar 3D object detectors. The code is available at https://github.com/HVXLab/HVDetFusio

    Structures of human gastrin-releasing peptide receptors bound to antagonist and agonist for cancer and itch therapy

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    Gastrin releasing peptide receptor (GRPR), a member of the bombesin (BBN) G protein-coupled receptors, is aberrantly overexpressed in several malignant tumors, including those of the breast, prostate, pancreas, lung, and central nervous system. Additionally, it also mediates non-histaminergic itch and pathological itch conditions in mice. Thus, GRPR could be an attractive target for cancer and itch therapy. Here, we report the inactive state crystal structure of human GRPR in complex with the non-peptide antagonist PD176252, as well as two active state cryo-electron microscopy (cryo-EM) structures of GRPR bound to the endogenous peptide agonist gastrin-releasing peptide and the synthetic BBN analog [D-Ph

    Sequential element extraction of soils from abandoned farms: an investigation of the partitioning of anthropogenic element inputs from historic land use

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    Enhanced soil element concentrations may serve as indicators not only of modern pollution, but also of former historic and/or pre-historic human activity. However, there is little consensus over the most appropriate means of extraction for identifying chemical signatures of modern and archaeological pollution. This study addressed this question by using a 5-step sequential extraction to examine the partitioning of elements within the soil. Samples were taken from known functional areas (hearth, house, byre, arable, and grazing areas) on a 19th century abandoned croft (small farm). A hot nitric acid digest and five-stage sequential extraction method were used to examine the partitioning of elements in soil and identify the current elemental distribution of anthropogenic contamination. The results indicate that although a significant proportion of Ca tends to be bound with exchangeable and weak acid soluble fractions, in the hearth and house areas there is also a significant proportion held within the recalcitrant residue. Pb concentrations tend to be associated with organic matter, ammonium oxalate extractable fractions and the residue, whilst Zn generally has a more even partitioning between the six soil fractions. The implications of this for extraction methodology are element and soil specific. However, the presence of a significant proportion of anthropogenically significant elements (including Ca, Pb, Zn, Sr, and Ba) within the resistant residue suggests the use of only a weak acid or an exchangeable fraction extraction would result in the loss of information from contamination resulting from former human activity. Hence, a total or pseudo-total extraction method is recommended for this type of study

    Zhang, et al, Expression of iKIR-HLA-Cw in patients with inflammatory bowel disease Expression of iKIR-HLA-Cw in patients with inflammatory bowel disease

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    Abstract Objective. To investigate the distribution of inhibitory killer cell immunoglobulin-like receptor (iKIR) and its ligand human leukocyte antigen C locus (HLA-Cw) in patients with inflammatory bowel disease (IBD), and explore whether iKIR/HLA-Cw combinations are associated with IBD susceptibility. Methods. The iKIR in 100 patients with ulcerative colitis (UC), 52 patients with Crohn's disease (CD) and 106 randomly ethnically matched healthy controls was phenotyped by sequence-specific primer PCR (PCR-SSP). HLA-Cw was phenotyped by CLOCUS SSP UNITRAY ® . The combination of HLA-Cw and its corresponding iKIR in individual was analyzed subsequently. Results. The KIR2DL1 and KIR2DL3 gene phenotype frequencies in UC patients were 0.710 and 0.620 respectively, both significantly lower than those in healthy controls, and the KIR2DL1 gene phenotype frequency in CD patients was 0.731, significantly lower than that in healthy controls. KIR2DL1-HLA-C2 combination in patients with UC and CD were 0.380 and 0.404 respectively, both significantly lower than that in healthy controls. Conclusion. The susceptibility to IBD is associated with decreased KIR2DL1-HLA-C2 combination

    Comparison of the Inhibitory Potential of Bavachalcone and Corylin against UDP-Glucuronosyltransferases

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    Bavachalcone and corylin are two major bioactive compounds isolated from Psoralea corylifolia L., which has been widely used as traditional Chinese medicine for many years. As two antibiotic or anticancer drugs, bavachalcone and corylin are used in combination with other drugs; thus it is necessary to evaluate potential pharmacokinetic herb-drug interactions (HDI) of the two bioactive compounds. The aim of the present study was to compare the effects of liver UDP-glucuronosyltransferase (UGT) 1A1, UGT1A3, UGT1A7, UGT1A8, UGT 1A10, and UGT2B4 inhibited by bavachalcone and corylin. 4-Methylumbelliferone (4-MU) was used as a nonspecific “probe” substrate. Bavachalcone had stronger inhibition on UGT1A1 and UGT1A7 than corylin which did not inhibit UGT1A1, UGT1A3, UGT1A7, UGT1A8, UGT1A10, and UGT2B4. Data fitting using Dixon and Lineweaver-Burk plots demonstrated the noncompetitive inhibition of bavachalcone against UGT1A1 and UGT1A7-mediated 4-MU glucuronidation reaction. The values of inhibition kinetic parameters (Ki) were 5.41 μM and 4.51 μM for UGT1A1 and UGT1A7, respectively. The results of present study suggested that there was a possibility of UGT1A1 and UGT1A7 inhibition-based herb-drug interaction associated with bavachalcone and provided the basis for further in vivo studies to investigate the HDI potential between bavachalcone and UGT substrates

    Exploring the experience of meaning-centered group psychotherapy among Chinese cancer patients during active treatment: a descriptive qualitative study

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    ObjectiveMeaninglessness poses a significant psychological challenge for cancer patients, negatively affecting their quality of life and increasing the risk of suicide. Meaning-Centered Group Therapy (MCGP) is an intervention designed specifically to enhance the meaning of life of cancer patients. Extensive research has documented its effectiveness across various cultures and populations. However, limited research has been conducted on the subjective experiences and perspectives of participants engaged in MCGP. Thus, the purpose of this study was to employ a qualitative design to explore the experiences and viewpoints of Chinese cancer patients who have undergone MCGP.MethodsWithin a two-week timeframe following the conclusion of MCGP, semi-structured interviews were administered to twenty-one participants who had engaged in the therapy. The interview data were transcribed and subjected to thematic analysis.ResultsFour main themes were identified: (a) Self-perceived personal change, (b) Overall experience of group therapy, (c) Barriers to participation of MCGP, and (d) Suggestions for future interventions.ConclusionDespite the barriers to participation in the MCGP process, the overall experience for Chinese cancer patients undergoing active treatment is valuable and positive, providing multiple benefits. Future studies could explore the adaptation of MCGP to a broader range of cancer populations and diverse study populations

    Ambient volatile organic compounds in a suburban site between Beijing and Tianjin : Concentration levels, source apportionment and health risk assessment

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    Volatile organic compounds (VOCs) have vital implications for secondary pollutants, atmospheric oxidation and human health. Ambient VOCs were investigated using an online system, gas chromatography-mass spectrometry/flame ionization detector (GC-MS/FID), at a suburban site in Xianghe in the North China Plain from 6 November 2017 to 29 January 2018. Positive matrix factorization (PMF) receptor model was applied to identify the major VOC contributing sources. Four-step health risk assessment method was used to estimate risks of all risk-posing VOC species. A total of 101 VOCs were quantified, and the mean concentration of total VOCs was 61.04 +/- 65.18 ppbv. The VOCs were dominated by alkanes (38.76%), followed by alkenes, aromatics, halocarbons, OVOCs, acetylene and acetonitrile. The results of PMF revealed that vehicle exhaust, industrial emissions, liquefied petroleum gas & natural gas, solvent utilization and secondary and long-lived species contributed 31.0%, 26.4%, 18.6%, 13.6% and 10.4%, respectively, to the total VOCs. Pollutant-specific and source-specific non-carcinogenic and carcinogenic risk estimates were conducted, which showed that acrolein and vehicle exhaust had evident noncarcinogenic risks of 4.9 and 0.9, respectively. The carcinogenic risks of specific species (1,3-butadiene, acetaldehyde, benzene, chloroformand 1,2-dichloroethane) and identified sources were above the United States Environmental Protection Agency (USEPA) acceptable level (1.0 x 10(-6)) but below the tolerable risk level (1.0 x 10(-4)). Vehicle exhaust was the largest contributor (56.2%) to noncarcinogenic risk, but solvent utilization (32.6%) to carcinogenic risk. Moreover, with the evolution of pollution levels, almost all VOC species, contributions of alkenes, aromatics, solvent utilization and vehicle exhaust, and pollutant-specific and source-specific risks increased continuously and noticeably. Collectively, our findings unraveled the importance of alkenes, aromatics, solvent utilization and vehicle exhaust in the evolution of pollution levels. Future studies should consider targeting these VOC groups and sources when focusing on effective reduction strategies and assessing public health risks. (c) 2019 Elsevier B.V. All rights reserved.Peer reviewe

    Exploring the inorganic and organic nitrate aerosol formation regimes at a suburban site on the North China Plain

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    Nitrate-driven aerosol pollution frequently occurs during winter over the North China Plain (NCP). Extensive studies have focused on inorganic nitrate formation, but few have focused on organic nitrates in China, preduding a thorough understanding of the nitrogen cycle and nitrate aerosol formation. Here, the inorganic (NO3,inorg) and organic nitrate (NO3,org) formation regimes under aerosol liquid water (ALW) and aerosol acidity (pH) influences were investigated during winter over the NCP based on data derived from an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). The campaign-averaged concentration of the total nitrate was 53 mu g m(3), with a 13% contribution from NO3,org, which exhibited a significantly decreased contribution with increasing haze episode evolution. The diurnal cycles of NO3,inorg and NO3,org were similar, with high concentrations during the nighttime at a high ALW level, revealing the important role of aqueous-phase processes. However, the correlations between the aerosol pH and NO3,inorg (R-2 = 0.13, P <0.01) and NO3,org (R-2 = 0.63, P <0.01) during polluted periods indicated a contrasting effect of aerosol pH on inorganic and organic nitrate formation. Our results provide a useful reference for smog chamber studies and promote a better understanding of organic nitrate formation via a nthropogenic emissions. (C) 2021 Elsevier B.V. All rights reserved.Peer reviewe
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