Accretion onto a Kiselev black hole

We consider accretion onto a Kiselev black hole. We obtain the fundamental equations for accretion without the back-reaction. We determine the general analytic expressions for the critical points and the mass accretion rate and find the physical conditions the critical points should fulfill. The case of polytropic gas are discussed in detail. It turns out that the quintessence parameter plays an important role in the accretion process.Comment: 7 page

Optimal Estimation of a Classical Force with a Damped Oscillator in the non-Markovian Bath

We solve the optimal quantum limit of probing a classical force exactly by a damped oscillator initially prepared in the factorized squeezed state. The memory effects of the thermal bath on the oscillator evolution are investigated. We show that the optimal force sensitivity obtained by the quantum estimation theory approaches to zero for the non-Markovian bath, whereas approaches to a finite non-zero value for the Markovian bath as the energy of the damped oscillator goes to infinity.Comment: 5 pages, 4 figure

Expression of miR-21 in Colorectal Cancer and Its Relationship with Clinicopathological Characteristics of Colorectal Cancer

Objective: To investigate the expression of miR-21 in colorectal cancer cells, and to analyze the relationship between the level of miR-21 and the clinicopathological characteristics of colorectal cancer patients. Methods: 210 patients with colorectal cancer treated in our hospital from January 2016 to June 2019 were selected. Cancer tissue specimens (study group) and adjacent normal tissue specimens (control group) were surgically collected, and the quantitative quantitative PCR was used to detect and compare the miR-21 expression of the two groups. Results: The expression of miR-21 in the study group was higher than that in the control group, and the difference was statistically significant (P <0.05). There were significant differences among patients with early and intermediate TNM, patients with low differentiation and patients with moderate to high differentiation, patients with lymph node metastasis and patients without lymph node metastasis, patients with high infiltration and patients with low infiltration, patients with high CEA levels, and patients with low CEA, and the difference was statistically significant (P <0.05). Conclusion: In colorectal cancer, miR-21 is highly expressed, which is closely related to stage and differentiation, and can be used to reflect the patient’s condition

A Brief Summary of the Development of Farmer Cooperatives in China

Oral Presentatio

A study on QOS routing for providing guaranteed services under multi-class traffic loads

Master'sMASTER OF ENGINEERIN