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With the increase of energu demand of oil and gas and the decrease of conventional oil and gas resources in China, the exploration and development of tight gas reservoirs has becomes the first priority to enlarge gas reserves. The middle-deep sandstone of the Huagang Formation in the Xihu Sag of the East China Sea belongs to the category of tight sandstone reservoirs and is a typical low-permeability, low-porosity reservoir[Xu,G et al. 2012], with strong water-blocking damage, and drill-stem test (DST) results from many wells were showed much lower production than what expected. Conventional productivity evaluation methods are also difficult to accurately evaluated productivity with water-blocking damage condition. In this paper we integrated core experiment, water-drive gas experiment, gas-drive water experiment, wireline formation test (WFT) results, logging interpretation, formation evaluation results, and numerical simulation analysis and proposed a new production prediction solution for a tight gas formation with strong water-blocking damage. The workflow is following: First, mobility as a dynamic measurement derived from WFT was studied, which clarified that the near-wellbore zone has experienced water-based mud invasion. Second, based on WFT, core lab data, well logging interpretation results, and neural network rock typing method, the formation was characterized into different rock types. The characteristics of each rock type and its degree of water-blocking damage were researched. Then based on dozens of core lab data, the relationship between maximum gas relative permeability (Krg) and absolute permeability was identified. Furthermore, based on the correlation among core lab data, well logging interpreted permeability curve and maximum Krg, the effective permeability profile can be deduced. This profile can help to estimate the approximate maximum productivity of a well, but not accurately enough without irreducible water saturation input. Third, with calibrated permeability and saturation, a single well model was built with different rock typing results. Each rock type was assigned with the corresponding relative permeability lab data. By this, the process of productivity prediction from the different rock types and the effect of water-blocking damage with the changing of water saturation can be demonstrated. This solution cannot only simulate gas production with water saturation changing at the initial stage of production, but also simulates the water-blocking damage caused by mud invasion into the formation. It reproduces the generation and release process of "water-blocking." After verification with multiple wells, this solution can accurately provide production evaluation for a tight gas reservoir with water-blocking damage. It also confirmed the influence of water blocking on tight gas production.

Vertex-primitive self-complementary graphs were proved to be affine or in product action by Guralnicket al.[‘On orbital partitions and exceptionality of primitive permutation groups’,Trans. Amer. Math. Soc.356(2004), 4857–4872]. The product action type is known in some sense. In this paper, we provide a generic construction for the affine case and several families of new self-complementary Cayley graphs are constructed.

BACKGROUND: Lung cancer is one kind of malignant tumor with a high risk for morbidity and mortality compared to other solid organ malignancies. Brain metastases occur in 30–55% of non-small cell lung cancer (NSCLC) patients. Prognosis of NSCLC patients with brain metastases is very poor. Our previous study showed that cell adhesion molecule 2 (CADM2) could regulate the development of brain metastasis in NSCLC cells. Therefore, the objective of the study is to evaluate the effect of CADM2 on the prognosis of NSCLC patients with brain metastases. METHODS: The expression of CADM2 was detected by quantitative real-time polymerase chain reaction (qRT-PCR) in the tissue of the primary tumor. Patients were followed up and overall survival (OS) was calculated. The relationships between CADM2 and clinicopathological features were analyzed using the chi-square test. Kaplan-Meier analysis was carried out to demonstrate the influence of CADM2 on the OS of patients. Univariate and multivariate Cox analyses were used to determine the prognosis of NSCLC patients with brain metastases. RESULTS: A total of 139 NSCLC patients with brain metastases from the Affiliated Cancer Hospital & Institute of Guangzhou Medical University, treated between January 2015 and December 2017 were evaluated retrospectively. The expression level of CADM2 in patients ranged from 1 to 17.2677, with a median of 6.0772. Chi-square analysis showed that CADM2 gene expression level was not significantly associated with gender, age, tumor location, histological subtype, tumor T stage, extracranial metastasis, or smoking status. However, CADM2 expression was notably associated with risk for lymph node metastasis. The results of the Kaplan-Meier analysis showed that high expression [CADM2 messenger RNA (mRNA) ≥6.0772] of CADM2 was markedly associated with poor prognosis. Univariate and multivariate Cox analyses demonstrated that CADM2 was an independent risk factor for survival in NSCLC patients with brain metastases (P

The microstructure evolution and grain-refining mechanism in the process of ultrafine grain preparation with combination of different heat treatments and warm deformation were studied. 5140 steel，medium carbon low alloy steel, was used in this experimental and divided into three groups, which is one time quenching state, three times cyclic quenching state and original state without any heart treatment as the control group. All the samples of above three groups hold at 600°C for 5 min, then warm deformation was carried out immediately in YJ-450 Four-Pillar Hydraulic Machine. The deformation amount of above samples is controlled beyond 50%. The result shows that microstructure of the medium carbon steel samples after once quenching treatment and three times cyclic quenching treatments was significantly refined after warm deformation. The grain-refining mechanism of supersaturated single-phase ferrite in warm deformation is that new dislocation boundaries are produced continuously through dislocation cross-slip, which segments and refines the original grains. The grain size of three times quenching state after warm deformation is obviously finer than the grain size of one time quenching state after warm deformation under the same condition. And quenching times is a very significant factor to the extent of fining grain after warm deformation. Through three times cyclic quenching treatments and warm deformation, the size of grains has reached nano-scale.

We prove that the automorphism group of a self-complementary metacirculant is either soluble or has $$\mathrm{A}_5$$ A 5 as the only insoluble composition factor, extending a result of Li and Praeger which says the automorphism group of a self-complementary circulant is soluble. The proof involves a construction of self-complementary metacirculants which are Cayley graphs and have insoluble automorphism groups. To the best of our knowledge, these are the first examples of self-complementary graphs with this property.

In this short paper, we characterise graphs of order $pq$ with $p, q$ prime which are self-complementary and vertex-transitive.

A graph Γ is self-complementary if its complement is isomorphic to the graph itself. An isomorphism that maps Γ to its complement Γ is called a complementing isomorphism. The majority of this dissertation is intended to present my research results on the study of self-complementary vertex-transitive graphs. I will provide an introductory mini-course for the backgrounds, and then discuss four problems: constructions of self-complementary vertex-transitive graphs, selfcomplementary vertex-transitive graphs of order a product of two primes, selfcomplementary metacirculants, and self-complementary vertex-transitive graphs of prime-cube order. The main analysis on these problems relies on the two pivotal results due to Guralnick et al. [22] and Li, Praeger [31], which characterise the full automorphism group of a self-complementary vertex-transitive graph in the primitive and the imprimitive cases respectively. For constructions of self-complementary vertex-transitive graphs, there are generally three known construction methods: construction by partitioning the complementing isomorphism orbits; construction using the coset graph; the lexicographic product. In this dissertation I shall develop various alternative construction methods. As a result, I find a family of self-complementary Cayley graphs of non-nilpotent groups, a new construction for self-complementary metacirculants of p-groups. A complementing isomorphism of a self-complementary graph is an isomorphism between the graph and its complement. For the self-complementary vertex-transitive graphs whose automorphism groups are of affine type, we have obtained a characterisation of all their complementing isomorphisms. Furthermore, we provide a construction of self-complementary metacirculants which are Cayley graphs and have insoluble automorphism groups. This is the first known example with this property in the literature. For the self-complementary vertex-transitive graphs of order a product of two primes, we give a complete classification of these graphs: they are either a lexicographic product of two self-complementary vertex-transitive graphs of prime order, or a normal Cayley graph of an abelian group. A graph is called a metacirculant if its full automorphism group contains a transitive metacyclic subgroup. We shall explore self-complementary metacirculants and show that the full automorphism group of these graphs is either soluble or contains the only insoluble composition factor A5. This extends a result due to Li and Praeger [32] which says that the full automorphism group of a self-complementary circulant is soluble. Finally, we will investigate self-complementary vertex-transitive graphs of primecube order. We successfully show that for each type of the groups of prime-cube order, there exist self-complementary Cayley graphs of the corresponding groups. Moreover, we also gain a characterisation of all the self-complementary vertextransitive graphs of prime-cube order: they are normal Cayley graphs, or a lexicographic product of two smaller self-complementary vertex-transitive graphs, or their automorphism group is soluble.

To investigate the effects of ischemic post-conditioning (IPO) on the lung endogenous oxidant-antioxidant system and nitric oxide level during the early stage of ischemia/reperfusion (I/R) injury.Twenty four male Sprague-Dawley rats were randomly divided into 3 equal groups: sham-operation (S) group, I/R Group, undergoing ischemia by blocking the lung hilus for 1 h and then reperfusion for 30 min, IPO Group, undergoing blocking the lung hilus for 1 h and then 3 cycles of 10 s ischemia and 10 s reperfusion. Then the rats were killed with their lungs taken out. The levels of glutathione (GSH), nitric oxide (NO), malondialdehyde (MDA), xanthine oxidase (XO), and endogenous antioxidant enzymes, i. e, superoxide dismutase (SOD), and catalase (CAT), and activities of gultathionine peroxidase (GPX) and myeloperoxidase (MPO), a neutrophil accumulation marker, were measured respectively.In IPO group, Compared with I/R group, antioxidant systems such as the levels of SOD, CAT, GPX, and GSH of IPO Group were (41.4 +/- 4.4 ) U/mg, (19.5 +/- 1.6) U/mg, (168 +/- 13) U/mg, and (1.72 +/- 0.26) U/g, all significantly higher than those of I/R Group [(19.6 +/- 2.8) U/mg, (8.4 +/- 0.8) U/mg, (72 +/- 8) U/mg, and (0.89 +/-+/- 0.07) mg/g respectively, all P0.05); and the levels of XO, MPO, and MDA of Group IPO were (50 +/- 6) U/g, (5.0 +/- 0.5) U/g, and (0.91 +/- 0.08) nmol/mg respectively, all significantly lower than those of I/R Group [(83 +/- 8) U/g, (7.6 +/- 0.7) U/g and (1.58 +/- 0.17) nmol/mg respectively, all P0.05). The endogenous NO level of IPO Group was (93 +/- 7) micromol/g, significantly higher than that of I/R Group [(22 +/- 4) micromol/g, P0.01].Post-conditioning at onset of reperfusion reduces lung I/R injury. The lung protection of IPO may be mediated, in part, by inhibiting the oxidant generation and oxidizing, and may be associated with the increasing of the endogenous NO level.