Ants from northern Arizona and southern Utah

Ants of 22 species were collected in can pit-traps from 16 different vegetative associations to determine distribution, seasonal and annual occurrence, and population as bases for monitoring environmental impact. Thirteen species were sufficiently abundant and distributed to qualify as indicator species. Myrmecocystus mexicanus was the most widespread ecologically. Pogonomyrmex occidentalis was the most abundant species, but second in ecological distribution. The greatest number of species was found in the juniper- Ephedra -grass association, and the fewest species in Ephredra-Coleogyne-Grayia.        

Inhibition of liver fructose 1,6-bisphosphatase activity by Zn2+: reversal by imidazole pyruvate.

Imidazole pyruvate was found to be a very potent natural chelating agent in reversing the inhibition of liver fructose 1,6-bisphosphatase activity by Zn2+. This metabolite may play a physiological role in gluconeogenesis.     

约当重心定理的一个新证明

约当重心定理（１８６９年）提出，一棵树的重心不是由一个单一的顶点组成，就是由一对相邻的顶点组成－这篇文章提出了一个证明这个定理的新方法－     

Genetics of hybridization between the pocket gophers Thomomys bottae and Thomomys townsendii in northeastern California

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Terminal bud formation in limber pine

The progress of bud development was studied in limber pines growing in the mountains of northeastern Utah. Initiation of new bud scales began in mid-June, several weeks after elongation of the current shoot had begun. Needle primordia first appeared in September and continued to form through the winter, until all were present in May. This winter activity is believed to be fostered by surface temperatures on the terminal buds considerably higher than ambient air temperatures.     

A self-pollination experiment in Pinus edulis

Controlled pollinations were performed on four pinyons ( Pinus edulis Engelm.) to compare the results of selfing and outcrossing. Final cone size was the same under both treatments. There was no significant difference in number of seeds per cone. Filled-seed yields averaged 14.4 percent in selfings and 90.5 percent in outcrossings. Relative self-fertility averaged about 15 percent, a level comparable with that of other pine species studied.     

The Innovation Types Evaluation of Small Business

The technology innovation and technology innovation capability plays an important role in management study of small business's growth and development. In this paper, the types of innovation in small business are discussed. Then, a hierarchy comprehensive fuzzy index system evaluating the types of small businesses is proposed. Because of the fuzziness of 15 factors used to analyze the small business, L-R fuzzy number is applied to describe the basic fuzzy state index. Furthermore, the corresponding fuzzy evaluation algorithm is designed. An application example indicated the effects of the methods.     

水稻基因组——贫困地区的谷类作物占据了重要地位

由中国科学家独自绘制出的水稻基因组工作框架图 ,使人类首次在基因组层面上“认识水稻” ,为中国已进入世界生物学研究的前沿奠定了扎实的基础