Flow behavior of a coupled model between horizontal well and fractal reservoir

Many research findings have proven that the system of porous medium reservoirs exhibits different heterogeneous structures at various scales,demonstrating some form of self-similarity with fractal characteristics.In this paper,fractal theory is incorporated into the reservoir to investigate coupled flow between reservoir and horizontal well.By examining the pore structure of highly heterogeneous reservoirs,the fractal dimension can be determined.Analytical methods are utilized to solve the Green function of a point source in a reservoir with fractal characteristics.Employing Green's function and the principle of spatial superposition,a finite flow model for a horizontal well coupled with a fractal reservoir is developed to calculate the flow rate and flow profile of the horizontal well.The model also accounts for the impact of wellbore friction and is solved numerically.A specific example is used for calculation to analyze the influence of fractal parameters on the production and flow rate of the horizontal well.When considering the fractal characteristics of oil reservoirs,the flow rate of the horizontal well is lower than that in Euclidean space.As the fractal dimension increases,the connectivity of pores in the reservoir improves,making it easier to drive the fluid into the wellbore,and the flow distribution along the wellbore becomes more uniform.Conversely,as the anomalous diffusion index increases,the connectivity between pores deteriorates,thus the distribution of flow rate along the wellbore becomes more uneven.

新生儿桡动脉采血的方法探讨与护理体会

目的探讨新生儿桡动脉采血的方法与护理体会。方法选取2018年4月-2018年10月我院收治的70例进行桡动脉采血的新生儿,随机分为两组,每组35人。其中对照组均实施常规穿刺护理。实验组均实施优质桡动脉采血护理。观察并比较两组患儿穿刺成功率、局部瘀斑发生率,以及啼哭比例、采血前后心率上升幅度等。结果实验组患儿穿刺成功率明显高于对照组;而局部瘀斑发生率明显低于对照组,差异均有统计学意义(P<0.05);实验组患儿啼哭比例及采血前后心率上升幅度明显低于对照组,差异均有统计学意义(P<0.05)。结论桡动脉采血护理能够有效降低患儿痛苦,提高其一次性穿刺率,值得临床推广使用。

Light-shift induced by two unbalanced spontaneous decay rates in EIT(CPT)spectroscopies under Ramsey pulse excitation

Light shift is important and inevitably affects the long-term stability of an atomic clock.In this work,considering two unbalanced branches of the spontaneous decay rate in a three-level system,we studied the frequency shifts of electromagnetically induced transparency(EIT)and coherent population trapping(CPT)clocks operating under the pulse sequence regime by numerically solving the Liouville density matrix equations.The results show that the frequency shifts are larger when the two branches of spontaneous emission rate are not equal compared to the equal case.In addition,in EIT-Ramsey,the effect of the unbalanced branches of the spontaneous decay rate and relaxations of low-energy states on the frequency shift is greater than that of Rabi frequency.In CPT-Ramsey,the relaxations of low-energy states play a dominant role in frequency shift.

Research Progress of Immune Checkpoint Inhibitors in the Treatment of Hepatocellular Carcinoma

Hepatocellular carcinoma cells are relatively prone to metastasis and have a high degree of heterogeneity, making a successful cure rather difficult. In recent years, an increasing number of immune checkpoint inhibitors have been approved for listing. Due to their strong targeting and relatively low toxic and side effects, the application of immune checkpoint inhibitors in the treatment of hepatocellular carcinoma has become more widespread. Currently, the research on immune checkpoint inhibitors mainly concentrates on PD-1/PDL1, CTLA-4, TIM-3, LAG-3, and TIGIT. Although they have certain advantages, the occurrence of drug resistance has also been frequently observed in clinical practice, presenting certain limitations. This study examined the structural features of key immune checkpoints, and explored the clinical implementation of their inhibitors and drug resistance mechanisms, aiming to offer insights for improved use of immune checkpoint inhibitors in clinical settings.

From ultra-low friction to superlubricity state of black phosphorus:Enabled by the critical oxidation and load

Based on the density functional theory(DFT),we investigate the friction properties of inevitable oxidized black phosphorus(o-BP).o-BP with the weaker interlayer adhesion exhibits their great potential as a solid lubricant.At the zero load,the friction property of o-BP is adjusted by its oxidation degree.Expressly,ultra-low friction of P4O2(50%oxidation,O:P=2:4=50%)is obtained,which is attributed to the upper O atoms with lower sliding resistance in the O channel formed by lower layer O atoms.More attractive,we observe superlubricity behavior of o-BP at the critical load/distance due to the flattening potential energy surface(PES).The flattening PES is controlled by the electrostatic role for the high-load(P4O3,O:P=3:4=75%),and by the electrostatic and dispersion roles for the low-load(P4O2).Distinctly,the transform from ultra-low friction to superlubricity state of black phosphorus(BP)can be achieved by critical oxidation and load,which shows an important significance in engineering application.In addition,negative friction behavior of o-BP is a general phenomenon(Z>Z_(min),Z_(min)is the interlayer distances between the outermost P atoms of minimum load.),while its surface-surface model is different from the fold mechanism of the tip-surface model(Z_(0)<Z<Z_(min),Z_(0)is the interlayer distances between the outermost P atoms of equilibrium state.).Thus,this phenomenon cannot be captured due to the jump effect with instability of the atomic force microscopy(AFM)(Z>Z_(min)).In summary,o-BP improves the friction performance and reduces the application limitation,comparing to graphene(Gr),MoS2,and their oxides.

Observation of the ^1S0-^3P0 optical clock transition in cold ^199Hg atoms

We report on the observation of the highly forbidden ^1S0–^3P0 optical clock transition in laser-cooled ^199Hg atoms.More than 95% depletion of cold ^199Hg atoms is detected in the magneto-optical trap. Using the free-of-field detection method, the AC Stark shift from the cooling laser is removed from the in-field spectroscopy. At low-power clock laser pumping, the linewidth of the clock spectroscopy is approximately 450 k Hz（full width at half-maximum）, which corresponds to a Doppler broadening at the atom temperature of 60 μK. We determine the -1S0–^13P0transition frequency to be 1,128,575,290.819（14） MHz by referencing with a hydrogen maser and measuring with a fiber optical frequency comb. Moreover, a weak Doppler-free signal is observed.

Phenotypic and Functional Analysis of LCMV gp33-41-Specific CD8 T Cells Elicited by Multiple Peptide Immunization in Mice Revealed the Up-regulation of PD-1 Expression on Antigen-Specific CD8 T Cells

The phenotype and function of antigen-specific CD8 T cells are closely associated with the efficacy of a therapeutic vaccination. Here we showed that multiple immunizations with LCMV gp33-41 peptide （KAV） in Freund＇s adjuvant could induce KAV-specific CD8 T cells with low expression of CD127 and CD62L molecules. The inhibitory receptor PD-1 was also expressed on a substantial part of KAV-specific CD8 T cells, and its expression level on KAV-specific CD8 T cells in spleen and lymph nodes was much higher when compared to those in peripheral blood. Furthermore, KAV-specific CD8 T cells could specifically kill KAV-pulsed target cells in vivo but the efficiency was low. These data suggest that prime-boost vaccination schedule with peptide in Freund＇s adjuvant can elicit antigen-specific CD8 T cells of effector-like phenotype with partial functional exhaustion, which may only provide short-term protection against the pathogen. Cellular ＆ Molecular Immunology.