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It is important to clarify the characteristics of flow regimes underlying the debris bed formation behavior that might be encountered in core disruptive accidents of sodium-cooled fast reactors. Although in our previous publications, by applying dimensional analysis technique, an empirical model, with its reasonability confirmed over a variety of parametric conditions, has been successfully developed to predict the regime transition and final bed geometry formed, so far this model is restricted to predictions of debris mixtures composed of spherical particles. Focusing on this aspect, in this study a new series of experiments using nonspherical particles have been conducted. Based on the knowledge and data obtained, an extension scheme is suggested with the purpose of extending the base model to cover the particle-shape influence. Through detailed analyses and given our current range of experimental conditions, it is found that, by coupling the base model with this scheme, respectable agreement between experiments and model predictions for the regime transition can be achieved for both spherical and nonspherical particles. Knowledge and evidence from our work might be utilized for the future improvement of design of an in-vessel core catcher as well as the development and verification of sodium-cooled fast reactor severe accident analysis codes in China.

Aims: This study aimed to identify the different expression of circular RNAs (circRNAs) in the placental tissues of pregnant women with preeclampsia (PE) and to provide a new avenue of research regarding the pathological mechanisms of PE. Methods: In this study, we collected 40 placental tissues from PE patients and 35 placental tissues from gestational age-matched patients who gave premature birth. Arraystar circRNA Microarray Technology (KANGCHEN, Shanghai, China) was used to analyze the differential expression of circRNAs. According to the basic content of circRNAs in the two groups and their fold changes and due to the practicability of the designed divergent primers of each candidate circRNA, we selected three up-regulated circRNAs, hsa_circRNA_100782, hsa_circRNA_102682 and hsa_circRNA_104820, to validate the data. Real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was utilized to estimate the Ct values in both groups. We further evaluated the differences with a paired t-test and a receiver operating characteristic (ROC) curve. Results: Many circRNAs were found to be differentially expressed in PE placental tissues versus their controls; of these, 143 circRNAs were up-regulated and 158 were down-regulated. The expression levels of hsa_circRNA_100782 (p < 0.05), hsa_circRNA_102682 (p < 0.05), and hsa_circRNA_104820 (p < 0.0001) were validated as significantly up-regulated in the experimental group compared with the controls. Finally, we performed a literature comparison to forecast the possible mechanisms of circRNA function during PE. Conclusion: circRNA expression significantly differed in placental PE tissues compared with controls. According to the circRNA microarray results and the existing papers, circRNAs may contribute to the pathogenesis of PE by acting as miRNA sponges; this possibility requires additional investigation in future studies.

Background: The placenta acts not only as a conduit of nutrient and waste exchange between mother and developing fetus but also functions as a regulator of the intrauterine environment. Pre-eclampsia (PE) and gestational diabetes mellitus (GDM) are leading causes of complications during pregnancy. Pathophysiologies show that they are associated with one another. Epigenetics provides a link between environmental factors that have previously been linked to poor pregnancy outcomes and fetal programming. Methods and Results: The present study investigated genome-wide DNA methylation changes in PE and GDM compared with control subjects through DNA methylation microarray. We found that the methylation patterns of placentas from PE and GDM women were similar; 64.4% of the anno tated genes with differential methylation presented concordant changes between PE and GDM patients. Significantly, the same functional processes were affected by PE and GDM, with cell adhesion and cell differentiation being the most populated clusters and including genes related to carbohydrate metabolism and lipid metabolism. Conclusion: Our work showed that of DNA methylation patterns in human placentas are reliably and significantly associated with PE and GDM. DNA methylation status in the human placenta can function as a marker for the intrauterine environment and potentially play a functional role in PE and GDM development.

Aims: To investigate the contribution of dysfunction of maternal hemodynamics to renal impairment in preeclampsia (PE). Methods: Urinary protein excretion, serum creatinine, blood urea nitrogen, uric acid, and glomerular filtration rate were assessed in 571 pregnant women with PE in addition to and noninvasive hemodynamic monitoring. Patients were classified into two groups: PE with renal impairment (glomerular filtration rate 2, n = 161) and PE with normal renal function (n = 410). Cut-off values for hemodynamic parameters were calculated using receiver-operating characteristic curve analysis. Results: Maternal systolic function and cardiac output parameters were low and peripheral resistance was high in the PE renal impairment group. Cut-off values for the hemodynamic parameters, cardiac index, cardiac output, systemic vascular resistance index, and systemic vascular resistance were 2.85 l/min/m2, 5.25 l/min, 3,014.5 dyn s cm-5 m2 and 1,636.0 dyn s cm-5, respectively, according to receiver-operating characteristics curves. Conclusion: Renal impairment in PE is associated with reduced maternal cardiac output and increased peripheral resistance.

The impacts of suspended solids in secondary effluent on "tailing" phenomenon in disinfection of E. coli with chlorine were investigated using kinetic disinfection curves. Higher SS concentration led to earlier beginning of "tailing" region with lower inactivation level. Comparison between lg-lg regression analyses of disinfection curves demonstrated that the SS concentration correlated with overall inactivation rate, which decreased by 10 times while SS concentration increased from 6 to 85 mg/L. The results of segmental modeling of disinfection curves showed that the SS concentration (at a range of 10-55 mg/L) correlated with the starting time of "tailing" region as well as the log-kill at the starting point of tailing region (R20.99). The starting time was shortened from 330 min to 55 min, and the log-kill dropped from 5.8 down to 0.8 with SS concentration increasing. Better removal of SS will improve the lg-kill of E. coli at tailing region and the inactivation rate, resulting in lower cost of construction and running. In addition, higher chlorine dosage and lower pH value could slightly enhance the log-kill in the "tailing" region.