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There is fragmented land and fragile ecological environment in the loess hilly and gully region. With the rapid population growth and socio- economic development in recent years, the degree of fragmentation has been further aggravated. Therefore, based on the interpretation data of remote sensing images in 1990, 2000 and 2015, this paper uses Fragstats 4.2 to obtain the best analysis scale combined with the standard method and moving window method. On this basis, the spatial differentiation characteristics of each landscape index are explored; The spatial and temporal evolution process of watershed landscape fragmentation is revealed; The spatial autoregressive model is used to analyze the impact factors contributing to landscape fragmentation. The results show that with the change of grain size and extent, some landscape indices show a regularity to certain degree. The 90 m grid size and 900 m square window size are the best analysis scales in the Fenhe River Basin; patch density, contagion, effective grid size, and Shannon's diversity index have a spatial agglomeration effect in the three periods, and the spatial agglomeration type distribution has strong similarity. From 1990 to 2015, the spatial pattern of landscape fragmentation in the study area has obviously changed; the slope, elevation and distance from the construction land are the main factors affecting landscape fragmentation of river basin during the three periods. The research results can provide reference for landscape fragmentation analysis in Northwest China, and provide basis for future regional landscape pattern optimization and effective land management. [ABSTRACT FROM AUTHOR]

Objective: To compare the clinical efficacy and safety of nasal intermittent positive pressure ventilation and nasal continuous positive airway pressure in the treatment of respiratory distress syndrome of newborn. Methods: 94 cases of newborn with respiratory distress syndrome in our hospital from June 2014 to June 2015 were selected and randomly divided into two groups with 47 cases in each group, the control group was treated by Nasal continuous positive airway pressure and the experiment group 47 cases was treated by nasal intermittent positive pressure ventilation. The arterial blood gas analysis, oxygen inhalation time, hospital stay, clinical curative effect and complication rate were compared between two groups before and after treatment. Results: After treatment, the clinical efficacy of experiment group was significantly better than that of the control group. The level of pH and PCn in the experimental group were higher than those in the control group (P<0.05). the PaC'O, level was lower than the control group (P<0.05), the time of oxygen inhalation and the length of stay in hospital were lower than those in the control group (P<0.05). The success rate of the experimental group was higher than that of the control group, the treatment failure rate was lower than that of the control group (P < 0.05). The incidence rate of the experimental group was lower than that of the control group (P<0.05). Conclusion: The clinical efficacy and safety of nasal intermittent positive pressure ventilation were better than the nasal continuous positive airway pressure in the treatment of neonatal respiratory distress syndrome. [ABSTRACT FROM AUTHOR]

The practice teaching of electrical basic courses plays a key role to students? innovative ability with the major of electronic information. In view of the problems existing in the practice teaching of electrical basic courses, the paper takes teaching reform of Beijing Technology and Business University as an opportunity, puts forward to ability training as the goal, and builds a multi-platform, multi-level practice teaching system for these electrical basic courses. It has gradually increased the depth and difficulty of the practice content, implemented the bench experiment teaching of each other. Practice shows that the practice teaching system makes the students ’ quality and engineering ability gradually improvement and effectively improves innovation ability ultimately. [ABSTRACT FROM AUTHOR]

The upstream of the Fenhe River is a serious soil erosion area in the middle reaches of the Yellow River. In order to provide scientific and data support for soil erosion control, ecological management and rational land use in the upstream of the Fenhe River, based on the 2018 land use data, with the help of the revised general soil loss equation and geographic information system, remote sensing technology, the paper calculated the soil erosion modulus in the upstream of the Fenhe River and analyzed its spatial distribution. The results show that the maximum soil erosion modulus in the upstream of the Fenhe River is 48 117.1 t/ (km2·a), the average erosion modulus is 2 781.74 t/ (km² ·a) and the areas with higher erosion intensity are mainly distributed in the northeast and southwest; soil erosion of different land use types are quite different and soil erosion mainly occurs in woodland, artificial grassland and cultivated land areas with high altitudes, large slopes and low vegetation coverage, the potential soil erosion is relatively larger. The average erosion modulus of mining land, unused land, other woodland and garden land is also relatively larger. Land use control should be strengthened and grassland, woodland and cultivated land should be used rationally, put an end to deforestation, unreasonable mining, et al. and reduce man-made soil erosion as much as possible; with the increase in altitude, the intensity of soil erosion firstly increases sharply and then slowly decreases. 1200-2000 m is the main altitude section of soil erosion; the modulus of soil erosion increases with the increase of slope. The slope of 8°-35° is the serious area of soil erosion in the watershed and the key area of soil erosion control. [ABSTRACT FROM AUTHOR]

The optimization of the ecological security pattern is an important spatial way to ensure regional ecological security, maintain ecosystem stability and enhance ecosystem service. Taking the source area of Fenhe River Basin as an example, this paper quantitatively evaluated ecosystem services including water production, habitat quality and soil conservation, and used hot spot analysis to identify important ecological sources. Considering the complex mechanism of rivers in ecosystems, this paper established two ecological security patterns, and on this basis, put forward a comprehensive ecological security pattern. The results showed that there were 19 ecological sources in the source area of Fenhe River Basin, accounting for 16.59% of the total study area. Three ecological security patterns established 33, 42 and 43 potential ecological corridors respectively. The network structure evaluation results showed that three patterns could generate a closed ecological network. The total length of the optimized ecological corridor is 565.957 km, and comprehensive ecological security pattern had higher network closure, node connection rate and network connectivity, and the cost was relatively low. In addition, 35 ecological breakpoints were identified, and key areas for ecological protection and restoration construction were determined. This pattern can provide spatial guidance for regional ecological protection and restoration planning. [ABSTRACT FROM AUTHOR]

Obejective: To investigate the effects of propofol combined with dexmedetomidine on the analgesia in patients undergoing radical resection of lung cancer and its effect on stress response. Methods: 78 patients with radical resection of lung cancer from August 2014 to July 2016 were divided into the observation group and the control group according to the order of admission. The control group was given midazolam and dexmedetomidine for anesthesia. The observation group was treated with propofol combined with dexmedetomidine. The analgesic effect, mean arterial pressure, heart rate, blood glucose, interleukin-6(IL-6), interleukin-10 (IL-10), tumor necrosis factor-α(TNF-α) and total white blood cell count (WBC) levels in the two groups were compared. Results: The visual analogue (VAS) scores of patients in the observation group were significantly lower than those of the control group on waking up, at 10min and 30min after waking up (P<0.05), the levels of serum IL-6, TNF-α, WBC, heart rate, mean arterial blood pressure and blood glucose were significantly lower than those of the control group at 24 hours after treatment(P<0.05), and serum interleukin(IL-10) level was significantly higher than that of the control group <0.05). There was no significant difference in the incidence of adverse reactions between the observation group and the control group (P>0.05). Conclusions: Propofol combined with dexmedetomidine had good analgesic effect in the radical resection of lung cancer, and could effectively relieve the stress reaction with high safety. [ABSTRACT FROM AUTHOR]