An experimental study of imbibition process and fluid distribution in tight oil reservoir under different pressures and temperatures

Tight reservoirs are a major focus of unconventional reservoir development. As a means to improve hydrocarbon recovery from tight reservoirs, imbibition has been received increasing attentions in recent years. This study evaluates how the changes in temperature and pressure affect imbibition through conducting experimental tests under various conditions on samples from the Yan Chang formation, a tight reservoir in Ordos Basin. The fluid distribution is compared before and after imbibition in core samples by nuclear magnetic resonance method. The results show that the imbibition recovery is significantly improved through increasing temperature and pressure. A high temperature facilitates molecular thermal movements, increasing oil-water exchange rate. The core samples are characterized with nano-mesopores, which is followed by nano-macropores, micropores, mesopores, and nano-micropores. Comparative analysis of nuclear magnetic resonance shows that the irreducible water saturation increases after imbibition and is mainly distributed in nano-pores. Increasing pressure increases the amount of residual water in nano pores, with the relatively more significant increase in the amount of residual water in nanomacro-pores compared with other types of pores.Cited as: Liang, Y., Lai, F., Dai, Y., Shi, H., Shi, G. An experimental study of imbibition process and fluid distribution in tight oil reservoir under different pressures and temperatures. Capillarity, 2021, 4(4): 66-75, doi: 10.46690/capi.2021.04.0

The Research of Online Reviews’ Influence towards management response on Consumer Purchasing Decisions

With the growing population of online shopping, people pay more attention to online consumer reviews which influence consumer purchasing decisions. Consumer reviews are increasingly available online for a wide rage of products and services. This paper studies the impact of online reviews on the consumer purchasing decisions towards management response from four dimensions of online reviews number, review valance, review quality and management response by the method of experimental study, and builds the model of relationship between online reviews system and consumer purchasing decisions to test the moderating effect of management response in this model. The results show as follows: online review number, review valance, review quality and management response have a positive influence on consumer purchasing decisions; management response plays the significant moderating role in this process. As a result, characteristics of online review messages and management responses have a varying degree of impact on consumer purchasing decisions. We mainly discuss the implications of our findings for practice

Prediction scores of postoperative liver metastasis and long‐term survival of pancreatic head cancer based on the distance between the mesenteric vessels and tumor, preoperative serum carbohydrate antigen 19‐9 level, and lymph node metastasis rate

Abstract Background The shortest distance between the superior mesenteric artery (SMA) or superior mesenteric vein (SMV) and the tumor margin was combined with preoperative serum carbohydrate antigen (CA) 19‐9 and lymph node ratio (LNR) to evaluate joint effects on long‐term survival and liver metastasis in patients with pancreatic head cancer after radical surgery. Methods This retrospective study included 149 patients who underwent pancreaticoduodenectomy for pancreatic head cancer at Harbin Medical University Tumor Hospital from May 2011 to March 2021. The preoperative serum CA 19‐9 level and LNR were combined with the SMA or SMV distance. The joint association between long‐term survival and postoperative liver metastasis was evaluated. Results Based on the receiver operating characteristic curve of postoperative liver metastasis or long‐term survival, the optimal cut‐off values of SMV distance were 3.1 and 0.7 mm, respectively, whereas the optimal cut‐off value of SMA distance was 10.25 mm. The univariate model identified the liver metastasis score (p < 0.001) as a negative factor for postoperative liver metastasis of pancreatic head carcinoma. The SMV distance (p = 0.003), SMA distance (p < 0.001), LNR score (p < 0.001), and survival score (p < 0.001) were negatively correlated with long‐term survival after pancreatic head cancer. The multivariate model highlighted SMA distance (p < 0.001), survival score (p = 0.001), and LNR score (p < 0.001) as independent risk factors for long‐term survival in pancreatic head cancer. Conclusion Liver metastasis score may be an independent predictor of postoperative liver metastasis in patients with pancreatic head cancer. Survival and LNR scores may be independent predictors of long‐term postoperative survival in patients with pancreatic head cancer. However, the LNR score appears to improve long‐term survival

Developmental and reproductive toxicity of a recombinant protein subunit COVID-19 vaccine (ZF2001) in rats

Abstract ZF2001, a protein subunit vaccine against coronavirus disease 2019 (COVID-19), contains recombinant tandem repeat of dimeric receptor-binding domain (RBD) protein of the SARS-CoV-2 spike protein with an aluminium-based adjuvant. During the development of this vaccine, two nonclinical studies were conducted to evaluate female fertility, embryo-fetal development, and postnatal developmental toxicity in Sprague‒Dawley rats according to the ICH S5 (R3) guideline. In Study 1 (embryo-fetal developmental toxicity, EFD), 144 virgin female rats were randomly assigned into four groups and received three doses of vaccine (25 μg or 50 μg RBD protein/dose, containing the aluminium-based adjuvant), the aluminium-based adjuvant or a sodium chloride injection administered intramuscularly on days 21 and 7 prior to mating and on gestation day (GD) 6. In Study 2 (pre- and postnatal developmental toxicity, PPND), ZF2001 at a dose of 25 μg RBD protein/dose or sodium chloride injection was administered intramuscularly to female rats (n = 28 per group) 7 days prior to mating and on GD 6, GD 20 and postnatal day (PND) 10. There were no obvious adverse effects in dams, except for local injection site reactions related to the aluminium-based adjuvant (yellow nodular deposits in the interstitial muscle fibres). There were also no effects of ZF2001 on the mating performance, fertility or reproductive performance of parental females, embryo-fetal development, postnatal survival, growth, physical development, reflex ontogeny, behavioural and neurofunctional development, or reproductive performance of the offspring. The strong immune responses associated with binding and neutralising antibodies were both confirmed in dams and fetuses or offspring in these two studies. These results would support clinical trials or the use of ZF2001 in maternal immunisation campaigns, including those involving women with childbearing potential, regardless of pregnancy status

Additional file 1 of VDR promotes pancreatic cancer progression in vivo by activating CCL20-mediated M2 polarization of tumor associated macrophage

Supplementary Material