几个重要行列式的推导

作者在讲授工科类的“线性代数”课程时,结合课堂教学,对组合数学著名的Fibonacci数列Fn,应用行列式的性质推导出了F_n的一般表达式,并给出了几个有关行列式的恒等式,从而加深了学生对行列式和Fibonacci数列的认识。     

农业循环经济与农村先进文化建设

介绍了农业循环经济与农村文化及农村传统文化的关系,阐述了农村先进文化的表现、特点及对发展农业循环经济的意义,最后指出了建设农村先进文化的途径。     

新型曲柄连杆机构运动学模型的研究

提出一种用于内燃机的新型曲柄连杆机构,建立了该机构的运动学数学模型,并编制了计算机程序。根据程序输出结果对新型曲柄连杆机构的活塞运动规律进行了重点分析。结果发现,经过改进的新型曲柄连杆机构具有明显的活塞运动的非对称性,并简析了这种新特性有可能对内燃机工作过程产生的影响。     

水文地质数值模拟的立足点

根据当前水文地质数值模拟理论研究和实践应用的巨大反差，以五常市地下水资源数值模拟为例讨论了水文地质数学模型数值模拟的基础和立足点必须查明地质条件及水文地质条件并以大量的野外试验数据为依据，取得良好地质效果的数值模拟为例，进一步说明了野外基础工作的重要性。     

6110ZL增压中冷柴油机工作过程模拟计算

根据６１１０ＺＬ增压中冷柴油机工作过程的特点，建立了该发动机的数学模型，提出了进气终了状态估算方法及公式。提出了半涡轮叶轮计算方法，使单进口涡轮机一元流分析法得以在双进口无叶涡壳涡轮机上应用。编制出模拟计算软件     

Advanced glycosylation end products promote migration of podocytes through mTORC1/uPAR pathway

AIM: To investigate the influence of advanced glycosylation end products-modified bovine serum albumin (AGE-BSA) on mammalian target of rapamycin complex 1 (mTORC1), urokinase-type plasminogen activator receptor (uPAR), and cell mobility in the podocytes, and to further explore the probable relationship. METHODS: The conditionally immortalized mouse podocyte cell line was cultured in vitro. MTT assay and immunofluorescence were used to analyze the cell viability and cytoskeleton of the podocytes treated with the stimuli and intervention agents. The activity of mTORC1 and the expression level of uPAR in normal podocytes and podocytes treated with control BSA or AGE-BSA were detected by Western blotting. The migration ability of the podocytes was determined by would-healing assay. Rapamycin was added to inhibit the activity of mTORC1 along with the addition of AGE-BSA to observe the changes of uPAR and the motility of podocytes. RESULTS: No significant difference of the cell viability or cytoskeleton in the podocytes treated with the stimuli and intervention agents was observed. AGE-BSA up-regulated the activity of mTORC1 and the expression of uPAR, and induced the high mobility of the podocytes. Rapamycin obviously reduced the high expression level of uPAR and the increase in the migration ability of podocytes caused by AGE-BSA treatment. CONCLUSION: AGE-BSA might cause the high migration of podocytes through the mTORC1/uPAR signaling pathway.     

生物活性炭技术在印染废水深度处理中的应用研究

[目的]研究生物活性炭技术深度处理印染废水。[方法]利用生物活性炭技术对印染行业生化出水进行深度处理,探讨了生物活性炭滤塔运行方式、进水浓度、滤速等因素对处理效果的影响。[结果]上向流、进水CODCr浓度低于300 mg/L、滤速1.88 m/h是生物活性炭滤塔处理印染行业生化出水的合适工艺参数,并得到滤塔的反冲洗周期约为60 h。[结论]生物活性炭技术深度处理印染废水可以达到中水回用的目的。     

商业银行行业风险敞口与商业银行绩效

在无套利框架的基础上,讨论基于个体公平原则下的寿险产品定价问题,即运用倒向随机微分方程理论,将投保人和保险人置于同一系统中进行考虑：首先,根据双方的随机投资决策目标分别建立无套利寿险定价模型和动态资产份额定价模型,得出两个特殊线性倒向随机微分方程的显式解;然后,建立基于个体公平原则的寿险定价模型,从投保人和保险人双方的角度对寿险产品进行公平定价,得出了从供需双方考虑的投资回报定价公式;最后,利用所建立的模型进行案例分析,计算出基于个体公平原则的保费及保险公司的投资策略.该寿险产品定价模型不仅考虑了保险人的意愿,还同时考虑了投保人的实际情况,因此,按此定价理念开发出的保险产品,不仅可以提高产品研发的成功率,而且使得研发出的新产品更能在竞争激烈的保险市场中站稳脚步.     

Recruitment limitation in forests: Lessons from an unprecedented mountain pine beetle epidemic

Since the mid-1990s the forests of central British Columbia have undergone an unprecedented Mountain Pine Beetle (Dendroctonus ponderosae Hopkins) (MPB) epidemic that has resulted in extensive mortality of canopy lodgepole pine (Pinus contorta var. latifolia Engelm.). This study investigated how seed-source availability, seedbed substrate, overstory structure, and time since MPB attack interact to affect post-MPB seedling recruitment of the dominant tree species of these forests. In addition to post-MPB recruitment, these forests may be regenerated by trees established in the understory prior to MPB disturbance. Accordingly, we examined abundance and patterns of all regeneration less than 130 cm tall. We found post-MPB recruitment was sparse. Subalpine fir (Abies laciocarpa (Hook.) Nutt.) comprised the majority of the post-MPB recruitment. It increased with local parent tree basal area and increased strongly with proximity to a major seed source. This resulted in a patchy distribution for subalpine fir post-MPB regeneration. Lodgepole pine post-MPB recruitment was limited by overstory shading. Recruitment of pine decreased as the total overstory basal area increased. Interior spruce (Picea glauca × engelmannii) post-MPB recruitment was similarly limited by total overstory basal area. Seedbed substrates were uniform and dominated by moss. Substrate type distribution did not change as time since MPB disturbance increased. The overall low post-MPB recruitment observed was likely due to a lack of disturbance to the moss-dominated forest floor. Moss is known to be a poor substrate in northern forests. The distribution of all regeneration less than 130 cm tall showed the same trends as the post-MPB regeneration. We believe the post-MPB seedling recruitment dynamics of these forests was not substantially changed from conditions prior to MPB disturbance. There was no pulse of regeneration up to 10 years post-MPB disturbance. Unless this changes, future stand structure will be dominated by the seedling bank established prior to the MPB epidemic. Subalpine fir dominated the seedling bank (68%) and post-MPB recruitment (94%). This suggests that MPB-disturbed forests are undergoing a substantial shift in landscape-level species composition.