Solving Hitchcock''s transportation problem by a genetic algorithm

Genetic algorithms (GAs) employ the evolutionary process of Darwin's nature selection theory to find the solutions of optimization problems. In this paper, an implementation of genetic algorithm is put forward to solve a classical transportation problem, namely the Hitchcock's Transportation Problem (HTP), and the GA is improved to search for all optimal solutions and identify them automatically. The algorithm is coded with C and validated by numerical examples. The computational results show that the algorithm is efficient for solving the Hitchcock's transportation problem.     

Agrobacterium-mediated transformation of herbicide resistance in creeping bentgrass and colonial bentgrass

Embryogenic calli were induced from the seeds of creeping bentgrass (Agrostis palustris Huds.) cv. Regent and colonial bentgrass (Agrostis Tenuis Sibth. Fl. Oxen.) cv. Tiger. The embryogenic calli were precultured on fresh medium for 4-7 days and then co-cultivated with Agrobacterium tumefaciens, LBA4404, which contains plasmid vector-pSBGM harboring bar coding region, synthetic green fluorescent protein (sGFP) coding region and matrix attachment region (MAR). After 3 days of co-cultivation, the calli were washed thoroughly and transferred to MS medium containing 2 mg/L of 2, 4-D, 12-15 mg/L phosphinothricin (PPT) and 250 mg/L of cefotaxime. After 2-3 months of selection, the actively growing calli of 'Regent' and 'Tiger' were transferred to MS medium with 12-15 mg/L PPT and 250 mg/L cefotaxime for regeneration. The putative transformants were maintained on MS medium with 3 mg/L PPT for long period but control died within 1 month. After establishing in greenhouse, the transformants also showed strong resistance to 0.4% of herbicide Basta but control plants died within 2 weeks. Under confocal microscope, both young leaves and roots showed significant GFP expression. PCR analysis revealed the presence of a DNA fragment of GFP gene at the expected size (380 bp) in the transformants and its absence in a randomly selected control plant.     

School Subject Preferences: Age and gender differences revisited

As a follow-up to data collected in the early 1990s, rankings of school subject preferences were obtained from 144 girls and 218 boys aged 11-12 years, and 269 girls and 300 boys aged 15-16 years. The overall rankings showed evidence of the persistence of gender differences in preferences for a number of curricular areas. However, changes were also apparent. Practical subjects appeared further up the rankings than previously, particularly for the younger students. This finding may reflect a change in the status of such subjects relative to the more academic subjects. More inter-school variability between the subject preference orders was evident among the older than the younger students, suggesting a greater sensitivity to school-related factors among this age group.     

20世纪90年代河北省人口出生性别比真实水平的统计推断

普查资料显示,我国各省、市、自治区之间的人口出生性别比存在很大的差异性。通过对河北省"四普"和"五普"中同批人的统计资料分析表明,低年龄人口的漏报、瞒报现象是造成河北省出生性别比统计偏高的主要因素,但20世纪90年代出生人口性别比的真实水平仍然明显高于国际公认的正常水平。     

日本右翼极端主义的过去和现在

日本右翼极端主义是一种为日本扩张政策提供辩解和保护的思想,目的是“增强日本精神和日本民族主义”。被奉为现代化之父的福泽谕吉（Fukusawa Yukichi)就是一个极为顽固的右翼极端分子,他鼓励日本人的帝国主义倾向从而推动了当时日本的扩张政策。今天日本右翼极端主义表现出三种倾向：一种表现为不愿承认日本在二战中战败,有一定反美情绪;另外一种表现为新的保守主义;还有一种表现为传统的保守思想。     

民俗研究与翻译研究

每个民俗学学者必须了解自己的学科有多少经典或创新著作是翻译的结果,尽管这个问题常常被隐含了。民俗研究同时也是翻译研究,因为两个领域近年来愈发成熟和关系密切。无论是跨文化或语言研究还是对文化研究都离不开文本的翻译。这种翻译不仅能提供文本,同时也能在研究新的文化时促进文化协商。民俗学者必须面对民俗与翻译研究中出现的新问题。因此,可以通过回顾历史归纳出民俗与翻译研究的四个挑战。     

Training School Counselors To Work with Students with Handicapping Conditions

As students with handicapping conditions have been integrated into public schools, the role of the school counselor has been expanded to meet these students' needs. As a result, counselor training programs need to be adjusted to include theory and practice in working with exceptional children. In this article the authors discuss the issue of students with handicapping conditions in public schools and provide suggestions for training school counselors.     

信任与赋权文化在课程改革中的作用

近年来,课程改革研究者提倡在学校文化中加强赋权、信任等因素。本研究以新课程改革为背景,使用结构方程模型分析了信任与赋权文化、教师效能感与教师感受到的改革成效之间的关系。结果表明,信任与赋权文化总体上是增强教师效能感,进而改善改革成效的有效途径。然而,在发展信任与赋权的学校文化时,我们应注意赋权理念的文化适切性,鼓励教师参与那些和教学实践有关的项目的决策,而不是将所有学校事务都交由教师决定。