The influence of permeability and heterogeneity on chemical flooding efficiency and remaining oil distribution-based on NMR displacement imaging.

To investigate the impact of permeability and heterogeneity on oil displacement efficiency and remaining oil distribution of chemical flooding, three groups of high and ultrahigh permeability core samples from an ultrahigh water-cut oilfield in western China were selected as the research objects in this study. High-pressure mercury injection, scanning electron microscopy, wettability test, and other methods were used to characterize the reservoir properties of core samples. Six groups of experiments were performed using the nuclear magnetic resonance (NMR) displacement imaging technology to simulate the oilfield development process considering the economic benefits. The displacement stage with the best oil displacement effect in the process of waterflooding, chemical flooding and then waterflooding was defined, and the control effect of permeability and heterogeneity on the improvement of oil displacement efficiency by polymer-surfactant binary flooding was discussed. The distribution position of remaining oil in different displacement stages was quantitatively and visually displayed, and its control factors were revealed. The research shows that during the simulation process of first waterflooding followed by chemical flooding and then waterflooding in the oilfield, the T2 spectrum signal amplitude increases the most in the two stages, one is from saturated oil flooding to 50% water cut and the other one is from 95% water cut to the end of 1 PV polymer flooding. The oil displacement efficiency increases the most, and the oil is primarily discharged from pore throats larger than 90 ms (or with pore throat radius of 8.37 µm). Compared with heterogeneity, permeability plays a more obvious controlling role in improving the oil displacement efficiency of polymer-surfactant binary flooding. The influence of fingering phenomenon on the distribution of remaining oil is most obvious in the second waterflooding, and the distribution of remaining oil with polymer slug is more obviously affected by the fingering phenomenon than that with polymer-surfactant slug. The study results provide theoretical guidance for tapping the remaining oil potential of old oilfields with high to ultrahigh permeabilities.

Effects of Logotherapy-Based Mindfulness Intervention on Internet Addiction among Adolescents during the COVID-19 Pandemic.

BACKGROUND: The global outbreak of the novel coronavirus pneumonia (COVID-19) has seriously affected people's work and lives. Disaster-related traumatic stress events increase the risk of substance abuse. Therefore, the COVID-19 outbreak, as a stress event, inevitably has a negative impact on Chinese adolescents with Internet addiction. METHODS: In 2020, 1787 copies of the questionnaire were randomly distributed among adolescents aged 12-16 years in three communities in Shandong Province, China. Among the respondents, 121 Internet addicts voluntarily participated and were divided into the experiment group (60 members) and the control group (61 members). Logotherapy-based mindfulness intervention was carried out on the experiment group. The effects of the intervention were analyzed after eight weeks of intervention. RESULTS: After the intervention, significant decreases occurred in the scores of Internet addiction and its five dimensions in the experiment group (P < 0.05), thereby implying better invention effects in the experiment group than the control group. The experiment group exhibited an increase in the positive coping score and a decrease in the negative coping score (P < 0.05). Significant decreases were found in the anxiety and depression scores in the experiment group (P < 0.05). CONCLUSION: Logotherapy-based mindfulness intervention can significantly reduce the degree of Internet addiction among adolescents during the COVID-19 period, improve their positive emotions, reduce their negative emotions, and alleviate the degree of anxiety and depression in adolescents.

PDLIM5 improves depression-like behavior of prenatal stress offspring rats via methylation in male, but not female.

OBJECTIVE: Prenatal stress (PS) contributes to depression-like behavior in the offspring. PDLIM5 is involved in the onset of mental disorders. This study is to investigate the role and mechanism of PDLIM5 in depression-like behavior of PS offspring rats. METHODS: PS model was used to analyze the effects of different treatments to PS offspring rats with different sex, including PDLIM5, PDLIM5 shRNA and 5-aza-2' -deoxycytidine (5-azaD). The depression-like behavior was assessed by the sucrose preference test (SPT) and forced swimming test (FST). The mRNA and protein expression levels of PDLIM5 in the hippocampus of PS offspring rats were detected by qRT-PCR and western blot, respectively. The methylation of PDLIM5 promoter were analyzed by bisulfite sequencing. RESULTS: Our data revealed that PS offspring rats showed a significant decrease in sucrose preference and a prolonged immobility time. Injection of PDLIM5 significantly improved the depression-like behavior in PS offspring rats, whereas administration of PDLIM5 shRNA aggravated it. In addition, PDLIM5 expression was decreased at the mRNA and protein levels, and the methylation level of PDLIM5 promoter was increased in hippocampus of PS male but not female offspring rats. Furthermore, microinjection of 5-azaD improved the PS induced depression-like behavior in offspring rats. Moreover, in male PS offspring rats, microinjection of 5-azaD reversed the effect of PS on PDLIM5 expression and promoter methylation. CONCLUSION: PDLIM5 can significantly improve the depression-like behavior of both male and female PS offspring rats, while the PDLIM5 promoter methylation is only observed in male PS offspring rats. Our study may provide new mechanism for the pathogenesis of depression and experimental evidence for sex-based precise treatment.