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To clarify the influence of H2O thermal effect on the formation of ultrafine particulate matter (PM), Huangling coal char was burned in a high-temperature drop tube furnace at 1800 K under various O2/N2/H2O and O2/N2/H2O/Ar atmospheres. The introduction of Ar in the simulating atmosphere was designed to counteract the thermal effect of H2O. Results indicated that after eliminating the thermal effect of H2O, the yield of ultrafine PM continuously increased in higher H2O content. Compared with no H2O, the mass and number yield of ultrafine PM in O2/N2/H2O/Ar atmosphere with 30% H2O content increased by 35.5% and 58.9%, respectively. H2O thermal effect, gasification reaction, and char oxidation reaction during coal char combustion played a significant role in the formation of ultrafine PM. Oxidation reaction was the primary factor affecting the formation of ultrafine PM, and its relative contribution was more than 62.9%, whereas the thermal effect of H2O showed an overall negative net effect on the formation of ultrafine PM. With the H2O content varied from 5% to 30%, the contribution of H2O thermal effect to mass yield was in the range of −19.1% to −18.0%, while that to number yield was −33.1% to −30.6%. Once the H2O content reached 10%, the enhancing effect of H2O gasification reaction on the yield of ultrafine PM surpassed the negative contribution of H2O thermal effect. For a given H2O content, elevated O2 concentration weakened the negative contribution of H2O thermal effect. [ABSTRACT FROM AUTHOR]

Introduction. The association between Helicobacter pylori (H. pylori) infection and depression and anxiety has been reported in the literature. The aim of this meta‐analysis is to investigate the association of H. pylori infection with depression and anxiety. Methods. A systematic search was conducted in PubMed, Web of Science, Embase, and Chinese databases for observational studies that reported the incidence or prevalence of depression and anxiety in patients with H. pylori infection. We conducted meta‐analysis with a random‐effects model. Results. A total of twelve studies were included in this meta‐analysis. Significant and positive association was found for H. pylori infection with anxiety (OR 2.49, 95% CI 1.83–3.39), but not depression (OR 1.40, 95% CI 0.75–2.58). Subgroup analysis from study design noted a significant positive association between H. pylori infection and anxiety (case‐control and cross‐sectional study, OR 2.36, 95% CI 1.65–3.38; cohort study, RR 1.72, 95% CI 1.28–2.32). The similar trend among studies used the Self‐Rating Anxiety Scale (OR 2.43, 95% CI 1.78–3.32) and other questionnaires (OR 2.41, 95% CI 1.50–3.87) have been observed. However, subgroup analysis of the association between H. pylori infection and depression yields different results. Subgroup analysis from cohort studies noted a significant association between H. pylori infection and depression (RR 1.99, 95% CI 1.33–2.99), but not case‐control and cross‐sectional studies (OR 1.20, 95% CI 0.59–2.46). A significant positive association has been observed among studies used the Self‐Rating Depression Scale (OR 2.03, 95% CI 1.11–3.70), as opposed to studies using other questionnaires (OR 1.03, 95% CI 0.31–3.44). Conclusion. This meta‐analysis provide the support that a significant positive association between H. pylori infection and anxiety disorders. However, the association between H. pylori infection and depression appears to be insignificant. [ABSTRACT FROM AUTHOR]

Stable flow and discharge of the slag in an entrained flow gasifier are the key factors to ensure the long-term stable operation of gasifier. In this work, the melting and flow behavior of coal ash with different Fe2O3/SiO2 ratios was studied in a reduced atmosphere. The results show that the viscosity of slag decreases significantly with the increase of Fe2O3/SiO2. And the critical viscosity-temperature (TCV) decreases from 1309°C to 1226°C. It is found that more than 90% of iron ions exist in the form of Fe2+ in liquid slag by chemical titration. There are more simple ion clusters with low bridge oxygen number (BO) with the increase of Fe2+ and lead to depolymerization of slag. Furthermore, the ash with high SiO2 content can be transformed into slag with high viscosity at a low melting rate by the analysis of the slag area curve and X-ray diffraction pattern, which is considered to be controlled by the "softening-melting" mechanism. The ash with high Fe2O3/SiO2 can be transformed rapidly into a low viscosity liquid at a short melting interval, which follows the "melting-dissolution" mechanism. And it is helpful to promote the formation of low-temperature eutectics with the increase in Fe2O3/SiO2 by thermodynamic calculation. Research on the melting mechanism of slag will provide theoretical support for the regulation of slag flow characteristics. [ABSTRACT FROM AUTHOR]

Desmoid tumors (DTs), also called desmoid‐type fibromatoses, are locally aggressive tumors of mesenchymal origin. In the present study, we developed a novel mouse model of DTs by inducing a local mutation in the Ctnnb1 gene, encoding β‐catenin in PDGFRA‐positive stromal cells, by subcutaneous injection of 4‐hydroxy‐tamoxifen. Tumors in this model resembled histologically clinical samples from DT patients and showed strong phosphorylation of nuclear SMAD2. Knockout of SMAD4 in the model significantly suppressed tumor growth. Proteomic analysis revealed that SMAD4 knockout reduced the level of Cysteine‐and‐Glycine‐Rich Protein 2 (CSRP2) in DTs, and treatment of DT‐derived cells with a TGF‐β receptor inhibitor reduced CSRP2 RNA levels. Knockdown of CSRP2 in DT cells significantly suppressed their proliferation. These results indicate that the TGF‐β/CSRP2 axis is a potential therapeutic target for DTs downstream of TGF‐β signaling. [ABSTRACT FROM AUTHOR]

Liquid slag tapping at low operation temperature is a major challenge for the application of entrained-flow slagging gasifier. To obtain and elucidate a regulation on stable liquid slag tapping, the SiO2-Al2O3-(CaO+MgO+Na2O+K2O)-Fe2O3 phase diagrams of ash fusion temperatures as well as the ash viscosity and components were studied with ash fusibility apparatus, high-temperature viscometer, SEM-EDS and FactSage software. Meanwhile, the potential slagging properties were analyzed by the difference between soften temperature and deformation temperature (DSI), base/acid ratio (B/A) and slag viscosity index G. Results indicated that the contours of fluid temperature (FT) in the SiO2-Al2O3-(CaO+MgO+Na2O+K2O) pseudo-ternary diagrams presented inverted V-shaped distribution. Attributing to the positive effect of Al2O3 and the downward parabola effect of SiO2, the FT first decreased and then increased with the increased SiO2/Al2O3 at the minimum value of around 3.25. Also, with the increase of (SiO2+ Al2O3+ CaO+MgO+Na2O+K2O)/Fe2O3, the FT showed a V-type distribution with a minimum value at 94:6, yet the effect of Fe2O3 was slight. Besides, high content of CaO+MgO+Na2O+K2O effectively reduced the FT, which favored the formation of molten slag and operation economy; but it shortened the DSI, disadvantaging the formation of long slag and the operation stability. Moreover, decreased ratio of (CaO+MgO)/(Na2O+K2O) not only reduced the FT, but also enlarged the DSI. Finally, a regulation method concerning stable liquid slag tapping at low operation temperature based on ash fusion and slagging properties was proposed: adjusting SiO2/Al2O3 to 3.25 and the mass ratio of Fe2O3 nearby 6.0 wt.%, and doping CaO+MgO+Na2O+K2O with low (CaO+MgO)/(Na2O+K2O) ratio could effectively reduce the FT and viscosity and enlarge the DSI simultaneously, and vice versa. [ABSTRACT FROM AUTHOR]

The differences in the gas thermophysical properties (including heat capacity, thermal conductivity and diffusivity) between char combustion in wet and dry environments have remarkable influences on the combustion process. We conducted a detailed experimental study on the thermal effects of H2O on the coal char combustion at 1773 K in a high-temperature drop tube furnace (HTDTF). An appropriate portion of Ar was introduced into the bulk gas (O2/H2O/N2) during combustion to eliminate the opposed thermal effect of H2O. Results indicate that the H2O thermal effect initially increased with higher H2O concentrations from 0 to 10 vol.%, but it declined with a further increase in H2O concentrations in the bulk gas. Meanwhile, its effect was dominant in the preliminary and middle stages of char burning at low H2O concentrations. The increased H2O concentration and residence time promoted the gasification reaction and the water-gas shift reaction so as to weaken the negative thermal effect of H2O and improve the carbon conversion. In the 15%O2/5%H2O/80%N2 environment, the relative contribution of thermal effects to carbon conversion ratios ranked up to −36% at the residence time of 0.3 s, but it decreased to −0.3% at 21%O2/30%H2O/49%N2 atmosphere and the residence time of 0.4 s. [ABSTRACT FROM AUTHOR]