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In order to improve the anisotropy characteristics of permeability model in quantitatively describing mechanical deformation and permeability behavior of bedding coal rocks, take the fracture aperture of parallel bedding coal rocks as the benchmark, introduce the equivalent fracture aperture coefficient, and make the fracture aperture of non-parallel bedding coal rocks equivalent, we propose a permeability evolution model of bedding coal and rocks based on equivalent fracture aperture coefficient. The results show that with the increase of the bedding angle, the permeability of bedding coal and rocks decreases significantly, and the larger the bedding angle is, the smaller the dynamic permeability changes with the change of gas pressure; the adsorption effect has a significant impact on the evolution of permeability, but they are in a competitive relationship under different mechanical boundaries. The effect of effective stress on permeability is in a dominant position under the boundary of constant surrounding rock stress, while the adsorption effect is dominant under the fixed displacement boundary condition; for gas drainage of bedding coal and rock, drainage along the bedding direction can greatly improve the drainage efficiency.

To explore the structure of longan polysaccharide and its effect on macrophages, a homogenous polysaccharide (named LP) was isolated and purified from longan pulp by ethanol fractional precipitation, and the structure of LP was characterized by gel permeation chromatography with laser light scattering (GPC-LLS), infrared spectroscopy (IR) and nuclear magnetic resonance (NMR) spectroscopy. Meanwhile, its effect on the phagocytic capacity of macrophages and the secretion of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6. The results showed that LP was a heteropolysaccharide with a weight average molecular mass of 8.42 × 105 Da composed of glucose, galactose, mannose, mannuronic acid, arabinose and rhamnose at a molar ratio of 98.70% : 0.57% : 0.35% : 0.09% : 0.20% : 0.12%. NMR spectroscopic analysis showed the backbone chain structure of LP to be 6)-α-Glcp-(1→6)-α-Glcp-(14)-α-Glcp-(-1. LP at 50, 100, 200 μg/mL promoted the phagocytic capacity of macrophages and increased the secretion of TNF-α, IL-1β and IL-6. The phagocytic capacity of LP-induced macrophages increased by 95.61% compared with the untreated control group. TNF-α, IL-1β and IL-6 secretion in macrophages challenged by LP at 50, 100 and 200 μg/mL were 2.38, 10.51 and 10.67 times higher than those in the control group, respectively. These results showed that LP had an activating effect on macrophages, which can provide a scientific basis for the deep processing of longan fruit.

Coalbed methane (CBM) development in coal mining area has good safety, economic and energy benefits, but methane emission is common in surface well sites. In view of this, taking the CBM wells in Qinshui County of Shanxi Province as an example, the methane emission location and emission volume of CBM wells are obtained, and the prediction model of methane emission volume is established through field investigation and multiple regression analysis. The results show that 81% of CBM wells have methane emission. Wellhead and drainage outlet are the two main positions of methane emission. The proportion of wells with emission volume between 0-10 m3/d is 59%. On the whole, the emission accounts for 1.53% of the gas well production. There is almost no methane emission in the single liquid phase flow stage. The methane emission in the gas-liquid two-phase flow stage is positively correlated with the bottom hole flow pressure, times of stroke and gas production, and negatively correlated with the pump embedment and water production. The bottom hole flow pressure and the pump embedment have the greatest impact on the methane emission. In the single-phase gas flow stage, methane emission is positively correlated with gas production and casing pressure, and negatively correlated with stroke frequency and water production.

Taking Huolinhe Basin of Erlian Basin group and the low-rank coal reservoirs of Baiyinhua Basin as the research objects, through the analysis of the physical properties of coal reservoirs, mercury intrusion curve types, pore size distribution characteristics, pore structure types, the effect of the pore structure of low-rank coal reservoirs on coalbed methane adsorption and desorption in Erlian Basin provides a reference for the subsequent development of coalbed methane projects. The results show that the pore system of low coal rank coal reservoirs in Erlian Basin group is well developed and has large porosity. The porosity IV coal group

Honey pomelo, one of the most important fruits in China, always suffers a variety of diseases during the whole process of planting, such as maculopathy, anthracnose, scab and dark mildew, which seriously affects the fruit quality and yield. The accurate recognition of honey pomelo leaf diseases is the premise of the treatment of honey pomelo diseases, and the precision directly affects the efficiency in controlling diseases. However, most of the current researches on disease recognition aimed at the global information of the study objects, but ignored the disease's local feature extraction in multi-scale and multi-direction; in addition, the present researches generally used the method of "one to one" or "one to many" when building many types of support vector machine (SVM) in the disease classification model, few researches used the method about SVM based on directed acyclic decision tree. So, leaf diseases recognition of honey pomelo based on SVM of directed acyclic decision tree was put forward in this paper. At first, statistical analysis on components of color characteristics of collected honey pomelo leaf diseases was carried on, and the conclusion was drawn according to the statistics of component B, component 2G-R-B, component (G+R+B)/3 and component Q in YIQ color model, which were easily distinguished among the 4 diseases, and so the 4 color components were used as disease color features. Secondly, honey pomelo leaf disease images were converted into 4 grayscale images of component B, component 2G-R-B, component (G+R+B)/3 and component Q in YIQ color model. Gabor wavelet with 5 dimensions and 8 directions was used for convolution calculation with 4 grayscale component images, and 16-dimension energy sub-band was got, the mean value of which was used as eigenvector. Disease recognition model of three-level directed acyclic decision tree SVM was constructed by 6 SVM classifiers, in order to recognize 4 honey pomelo diseases, i.e. maculopathy, anthracnose, scab and dark mildew. According to the test results of cross validation method, the recognition accuracies of maculopathy, anthracnose, scab and dark mildew respectively reached 90%, 96.66%, 93.33% and 96.66%, and the average recognition rate of the 4 diseases was 94.16%, showing that the method could effectively recognize the 4 honey pomelo leaf diseases. Optimal binary tree SVM proposed in this paper was compared with BP neural network, one-to-one SVM and one-to-many SVM in different characteristic dimensions, and the results showed that the training time of the proposed method in this paper and other 3 methods was respectively 740 ms, 420 ms, 450 ms and 370 ms, and the disease recognition accuracy of the 4 methods was respectively 86%, 91.5%, 90% and 94.16%. The method proposed in this paper is superior to the other 3 algorithms in training time and recognition precision. So the proposed method can provide technical support for the accurate recognition of honey pomelo leaf diseases, in favor of the prevention and treatment of pomelo diseases, and also provide references for the prevention and cure of other plant's leaf diseases. [ABSTRACT FROM AUTHOR]

In this study the blood sample was collected from eighty-six athletes in Tibetan mountaining team and Tibetan mountaining sports school and ninety healthy Han nationality people in Guangdong province, and genomic DNA was extracted from peripheral leukocyte. The allele frequency distribution and the genotypes combination distribution of hypoxia-inducible factor-la gene (HIF-1alpha)exonl2 C1772T and G1790A were examined by restriction fragment length polymorphism PCR (PCR-RFLP) in order to evaluate the association of single nucleotide polymorphisms (SNPs) of HIF-1alpha C1772T and G1790A with hypoxic acclimation in high altitude in Tibetans. The results indicated that the genotype frequency of HIF-1alpha C1772T in Tibetan and in Han nationality was 13.95% versus 16.67% in genotype CC, 38.37% versus 41.11% in genotype CT and 47.68% versus 42.22% in genotype TT. No significant difference in CC, CT and TT genotype frequency of HIF-1alphaC1772T was shown between Tibetans and Han nationality respectively, while GA genotype frequency of HIF-la G1790A in Tibetans was higher than that in Han nationality. The GA genotype of HIF-1alpha G1790A may be involved in the hypoxic acclimation of high altitude , and it is worth of deep-going investigation.

This investigation was conducted to explore the relationship between the polymorphism of gene of glucose transport 1(GLUT1) and the human body adaptation to high altitude hypoxia environment. The data on glucose transport 1 gene polymorphism in Tibetan mountaineers (high altitude group) were analyzed and compared with the data from the level-land Guangdong Hans (control group). The genotype of 86 Tibetan mountaineers and 90 level-land Hans as controls were tested with polymerase chain reaction followed by restriction fragment length polymorphism analysis for GLUT1 gene. The results showed that, in the high altitude mountaineer group, the frequencies of +22999 locus genotypes GG, GT and TT were 44.2%, 46.5% and 9.3% respectively, and such frequencies in the control group were 66.7%, 31.1% and 2.2% respectively. The frequencies of + 22999 polymorphic genotypes and alleles showed statistically significant difference between the high altitude group and the control group (P<0.05). Genetic single nucleotide polymorphism in GLUT1 G+22999T may be associated with the adaptation to high altitude hypoxia.