园艺地布在现代果园行间管理中的应用

园艺地布覆盖是在果园行间铺设地布作为覆盖物的一种果园管理方法,在我国果园生产管理中应用起步较晚,缺乏研究。果树行间覆盖园艺地布具有保持土壤湿度、提高肥料利用率、增加果实产量、保持水土、减少氮素流失等重要作用。比较目前常见的果园行间管理方式与园艺地布覆盖的优缺点,分析投资成本,指出园艺地布覆盖技术要点,为该技术在现代果园中应用奠定基础。

园艺地布在现代果园行间管理中的应用

园艺地布是一种覆盖铺设在果园行间当作一种覆盖物的果园管理办法。这种关于果园行间管理的应用发展在我国的起源和发展较晚,而且在较长时间没有专业的研究人员对其进行深入研究。近年来随着科学技术等多方面的不断发展和进步,果树行间覆盖园艺地布的技术应用得到了较快发展,对果园的整个水土环境以及肥料的利用效益都有所提高。本文将重点对园艺地布在现代果园行间管理中的应用进行较为深入的分析和探讨。

Anterior resection for rectal carcinoma-risk factors for anastomotic leaks and strictures

AIM:To determine the incidence and factors responsible for anastomotic leaks and stricture following anterior resection(AR)and its subsequent management.METHODS:Retrospective analysis of data from 108 patients with rectal carcinoma who underwent AR or low anterior resection(LAR)to identify the various preoperative,operative,and post operative factors that might have influence on anastomotic leaks and strictures.RESULTS:There were 68 males and 40 females with an average of 47 years(range 21-75 years).The median distance of the tumor from the anal verge was 8 cm(range 3-15 cm).Sixty(55.6%)patients underwent handsewn anastomosis and 48(44.4%)were stapled.The median operating time was 3.5 h(range2.0-7.5 h).Sixteen(14.6%)patients had an anastomotic leak.Among these,11 patients required reexploration and five were managed expectantly.The anastomotic leak rate was similar in patients with and without diverting stoma(8/60,13.4%with stoma and 8/48;16.7%without stoma).In 15(13.9%)patients,resection margins were positive for malignancy.Ninteen(17.6%)patients developed anastomotic strictures at a median duration of 8 mo(range 3-20 mo).Among these,15 patients were successfully managed with per-anal dilatation.On multivariate analysis,advance age(>60 years)was the only risk factor for anastomotic leak(P=0.004).On the other hand,anastomotic leak(P=0.00),mucin positive tumor(P =0.021),and lower rectal growth(P=0.011)were found as risk factors for the development of an anastomotic stricture.CONCLUSION:Advance age is a risk factor for an anastomotic leak.An anastomotic leak,a mucin-secreting tumor,and lower rectal growth predispose patients to develop anastomotic strictures.

Correlation between time management disposition and ability confidence of chinese nursing students： a meta-analysis

Objective： To evaluate the correlation between time management disposition and ability confidence of Nursing Students in China through the Pearson correlation coefficient. Methods： Electronic databases including the Cochrane library, PubMed, EMBASE, the Web of Science, CBM, Wanfang, VIP and CNKI were searched from inception to October 2017 to collect literature on the correlation between time manage-ment disposition and ability confidence of Chinese nursing students. The studies were examined according to the inclusion and exclusion criteria. After extracting data and evaluating the quality of the included studies. Meta-analysis was carried out using Stata 12.0 software. Results： A total of 7 articles with 1632 nursing students were included, and the quality of the literature was at medium level. Meta-analysis shown the total score of time management disposition of Chinese nursing students and its three dimensions were related to ability confidence. The summary correlation coefficient between time management disposition and ability confidence was 0.52 （0.43 to 0.59） ; There is a weak correlation between time value and ability confidence （r, 0.33; 95% CI, 0.25 to 0.39）; There was a moderate level of correlation between time control and ability confidence （r, 0.49; 95% CI, 0.43 to 0.54）; There was a moderate level of correlation between time efficacy and ability confidence （0.47, 0.41, 0.53）.And the relevance of nursing time management disposition and behavioral confidence varies with the nursing student＇s area, nursing student＇s diploma, measurement tools and sample size. Conclusion： The time man- agement disposition of Chinese nursing students is moderately related to ability confidence. When there are different in nursing students in the area, nursing diploma, measurement tools and sample size, the relevance is very different. The time management disposition of Chinese nursing students and their ability confidence are mutually reinforcing, and the time management disposition and their ability confidence should be further strengthened in the future.

Vehicle Operating, Accident and User Time Costs in Pavement Management Systems： Approach for Portuguese Conditions

This paper presents a description and analysis of the most important models to predict each of the Road User Costs components （Vehicle Operating Costs, Accident Costs and Value of Time） and proposes a model for estimating RUC components suitable for the Portuguese road network. These results are part of a research which aimed to obtain a Road User Cost Model to be used as a tool in road management systems. This model is different from other models by the fact that it includes a simple formulation that allows calibration and calculation of cost parameters, for any year, in a simple and fast way, providing trustworthy results. The required data is already available in Portuguese institutions, allowing periodic revision of cost parameters to insure accuracy.

Human evacuation affected by smoke movement in mine fires

The objective of this work is to investigate the influence of smoke movement during mine fires on miner evacuation behaviors. A three-dimensional computational fluid dynamics method was conducted to reconstruct the lane- way conveyor belt fire scenes under two ventilating conditions. The parameters, including temperature-time histories, soot density, carbon monoxide and heat release rate, were simulated to characterize the mine fires at various ventilating speeds. A miner evacuation model affected by fire smoke movement was advanced to describe the miner evacuation behaviors, which can be divided into three stages. Based on the evacuation model coupled with the mine fire smoke movement, the available safety evacuation time for miners involved in coal mine fire located in different sites was estimated. Two evacuation patterns were advanced according to the ventilating speeds combined with the model of miner evacuation behaviors. The results show that the miners located between the inlet-air end and the air door in lane 1 should be evacuated to the inlet-air end and other miners involved in coal mine fire could choose the air door as the escaping destination, when the ventilation speed is greater than 3 m/s. Accordingly, the research can be used as references for the mine safety administration authorities to design the safety evacuation.

A Strategy of Density-Based Partitioning for Scalability Problem in Network Self-management

A density-based partitioning strategy is proposed for large domain networks in order to deal with the scalability issue found in autonomic networks considering, as a scenario, the autonomic Quality of Service （QoS） management context. The approach adopted focus as on obtaining dense network partitions having more paths for a given vertices set in the domain. It is demonstrated that dense partitions improve autonomic processing scalability, for instance, reducing routing process complexity. The solution looks for a significant trade-off between partition autonomic algorithm execution time and path selection quality in large domains. Simulation scenarios for path selection execution time are presented and discussed. Authors argue that autonomic networks may benefit from the dense partition approach proposed by achieving scalable, efficient and near real-time support for autonomic management systems.

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