X-ray fluorescent lines from the Compton-thick AGN in M51

The cold disc/torus gas surrounding active galactic nuclei (AGN) emits fluorescent lines when irradiated by hard X-ray photons. The fluorescent lines of elements other than Fe and Ni are rarely detected due to their relative faintness. We report the detection of Kα lines of neutral Si, S, Ar, Ca, Cr, and Mn, along with the prominent Fe Kα, Fe Kβ, and Ni Kα lines, from the deep Chandra observation of the low-luminosity Compton-thick AGN in M51. The Si Kα line at 1.74 keV is detected at ∼3σ, the other fluorescent lines have a significance between 2 and 2.5 σ, while the Cr line has a significance of ∼1.5σ. These faint fluorescent lines are made observable due to the heavy obscuration of the intrinsic spectrum of M51, which is revealed by NuSTAR observation above 10 keV. The hard X-ray continuum of M51 from Chandra and NuSTAR can be fitted with a power-law spectrum with an index of 1.8, reprocessed by a torus with an equatorial column density of NH ∼ 7 × 10^(24) cm^(−2) and an inclination angle of 74°. This confirms the Compton-thick nature of the nucleus of M51. The relative element abundances inferred from the fluxes of the fluorescent lines are similar to their solar values, except for Mn, which is about 10 times overabundant. It indicates that Mn is likely enhanced by the nuclear spallation of Fe

Influence of early post-burn enteral nutrition on clinical outcomes of patients with extensive burns

Sepsis commonly occurs in severe post-burn patients, often resulting in death. We aimed to evaluate the influence of early enteral feeding on outcomes in patients with extensive burns, including infection incidence, healing and mortality. We retrospectively reviewed 60 patients with extensive burns, 35 who had received early enteral nutrition and 25 who had received parenteral nutrition. Average healing time, infection incidence and mortality were clinically observed. Hemoglobin and serum albumin were monitored weekly in both groups during treatment. Causative organisms were identified in patients with sepsis. Infection incidence was significantly less in the enteral nutrition group than the parenteral nutrition group (17.1% vs 44.0%; p = 0.023); and latency duration was longer in the enteral nutrition group than in the parenteral nutrition group (30.5 ± 4.7 days vs 14.5 ± 2.3 days; p<0.001). Duration of antibiotic therapy of the enteral nutrition group was significantly shorter than that of the parenteral nutrition group (12.5 ± 3.0 days vs 19.8 ± 3.6 days; p<0.001). Mean hemoglobin results (10.1 ± 1.3 g/L vs 8.3 ± 1.5 g/L; p<0.001) and serum albumin results (44.7 ± 5.7 g/L vs 36.2 ± 6.9 g/L; p<0.001) of enteral nutrition and parenteral nutrition groups, respectively, provided an overview of systemic nutrition and protein metabolism, suggesting higher systemic nutrition and protein synthesis in enteral nutrition group than in parenteral nutrition group. Risk of post-burn infection is reduced in burn patients who are supported by earliest possible enteral nutrition

Abnormal bile acid metabolism is an important feature of gut microbiota and fecal metabolites in patients with slow transit constipation

Destructions in the intestinal ecosystem are implicated with changes in slow transit constipation (STC), which is a kind of intractable constipation characterized by colonic motility disorder. In order to deepen the understanding of the structure of the STC gut microbiota and the relationship between the gut microbiota and fecal metabolites, we first used 16S rRNA amplicon sequencing to evaluate the gut microbiota in 30 STC patients and 30 healthy subjects. The α-diversity of the STC group was changed to a certain degree, and the β-diversity was significantly different, which indicated that the composition of the gut microbiota of STC patients was inconsistent with healthy subjects. Among them, Bacteroides, Parabacteroides, Desulfovibrionaceae, and Ruminiclostridium were significantly upregulated, while Subdoligranulum was significantly downregulated. The metabolomics showed that different metabolites between the STC and the control group were involved in the process of bile acids and lipid metabolism, including taurocholate, taurochenodeoxycholate, taurine, deoxycholic acid, cyclohexylsulfamate, cholic acid, chenodeoxycholate, arachidonic acid, and 4-pyridoxic acid. We found that the colon histomorphology of STC patients was significantly disrupted, and TGR5 and FXR were significantly downregulated. The differences in metabolites were related to changes in the abundance of specific bacteria and patients’ intestinal dysfunction. Analysis of the fecal genomics and metabolomics enabled separation of the STC from controls based on random forest model prediction [STC vs. control (14 gut microbiota and metabolite biomarkers)—Sensitivity: 1, Specificity: 0.877]. This study provided a perspective for the diagnosis and intervention of STC related with abnormal bile acid metabolism

A Study of Income Segregation in Large Chinese Cities

Income segregation is an issue of great importance to scholars and policy makers because it is thought to exacerbate inequities of social outcomes such as education, social capital, and employment. China makes an ideal case study for the topic of income segregation. It has the largest population of any country, some of the highest levels of income inequality in the world, and many megacities. Using data from 20 large cities in China, this paper measures levels and patterns of income segregation in large Chinese cities with new measurement techniques. Findings show that there is a negative correlation between segregation levels of studied cities and their level of economic development and size, a sharp contrast to patterns in cities of the United States and Hong Kong. Additionally, the shape of the segregation profile varies greatly across the cities. There are three clear groups of cities based on their internal income segregation patterns. Possible explanations for the differences among these groups include the size of the built-up area, level of economic development, and the size of the immigrant population

THE GREAT URBAN SPRAWL IN CHINA: A STUDY OF WUHAN URBAN LAND EXPANSION BETWEEN 1996 AND 2014

Ph.DDOCTOR OF PHILOSOPHY (SDE

Integrative Transcriptomics and Proteomics Elucidate the Regulatory Mechanism of <i>Hydrangea macrophylla</i> Flower-Color Changes Induced by Exogenous Aluminum

The mechanism through which Hydrangea macrophylla are able to change color has been the focus of investigation for many studies. However, the molecular mechanism involved in the complexation of aluminum ions and anthocyanins to regulate the color change remains unclear. Here, the color-changing mechanism was investigated in Hydrangea macrophylla plants under aluminum stress using proteome and transcriptome sequencing methods. Catalase, peroxidase, superoxide dismutase, 3-O-delphinidin and Al3+ contents in sepal were significantly upregulated upon Al3+ treatment. Moreover, 1628 differentially expressed genes and 448 differentially expressed proteins were identified between the treated and untreated conditions. GO and KEGG enrichment analyses revealed that the differentially expressed genes and differentially expressed proteins were enriched in categories related to the cell wall, peroxidase activity, and peroxisome pathways. Importantly, eight genes involved in anthocyanin biosynthesis were significantly downregulated at the transcript and protein levels under aluminum stress. These results suggest that aluminum ions induce expression changes of related key genes, which regulate the hydrangea’s flower color. Overall, this study provides a valuable reference for the molecular mechanism relating to the color change and adaptation of Hydrangea macrophylla in response to aluminum stress