PHYLETIC RELATIONSHIP OF PROTEIN STRUCTURES BASED ON SPATIAL PREFERENCE OF RESIDUES

A distance measure that infers to indicate the evolutionary relationship of protein structures has been developed based on spatial preference factors of residues. The spatial preference factor is a reflection of the environment of residues in tertiary structure. Compared with the phyletic relationships derived from sequence homologies and three-dimensional structures, we find that the two lines of evolution are similar in general. This approach is applied to a group of glins here.

The preferences of orientations between the pairs of amino acids

In this work, we make an investigation on the preferences of orientations between amino acids using the orientation defined based on the local geometry of the amino acids concerned. It is found that there are common preferences of orientations （70°, 30°, 140°） and （110°, 340°, 100°） for various pairs of amino acids. Different side chains may strengthen or weaken the common preferences, which is related to the effect of packing. Some amino acids having specific local flexibility may possess some preferences of orientations besides the common ones, such as （10°, 280°, 210°）. Another analysis on the pairs of the amino acids with different secondary-structure preferences shows that the directional interaction may affect the distribution of orientation more effectively than the packing or local flexibility. All these results provide us some insight of the organization of amino acids in protein, and their relation with some related interactions.

The Structural Stability of Alpha-Helix Determined by the Preference of Amino Acids

To accomplish their functions, proteins have to achieve different conformations accompanied by conformational transitions. However, the relationship between the preference of amino acids and the stability of the secondary structure is still unclear. Here we perform molecular simulations on a series of helical structures. Our data show that the dissociation energy of the helical structure is related to the preference of amino acids, and the electrostatic repulsion of the residue i and i ＋ 3/4 with the same sign of charge destabilizes the alpha helix.

Ranking all decision making units based on their elementary differences

Traditional DEA-based ranking techniques have some pitfalls such as ignoring the inherent differences among decision making units （DMUs）, or lacking a common weight-based ranking, etc. To overcome these obstacles, the paper first examines the possible differences among all DMUs such as the technical efficiency difference, the preference structure difference and the within-group position difference. Based upon the above differences this paper induces an integrated ranking measurement which helps to give a fair and full ranking for all DMUs under evaluation. Following the three types of differences, this approach behaves greatly elaborately, accurately and reasonably. Finally, the results from the Olympics achievement evaluation approve the acceptability of this approach.

A structural relationship between place attachment and intention to conserve landscapes–a case study of Harz National Park in Germany

Place attachment is an important motivation for people to spend more time outdoors and to protect landscapes.This study explores visitors' intention to conserve natural landscapes based on the relationship with their place attachment to National Park landscape. Structural equation modelling(SEM) was used to determine the relationship between landscape conservation and place attachment. A survey with a structured questionnaire was administered to visitors to the seven designated hiking courses of Harz National Park in Germany. The path coefficient of 0.77 revealed that place dependence positively and significantly affected place attachment, whereas place identity did not. Place attachment had a significant effect on both affective appraisals and visiting satisfaction. Higher place attachment led to higher emotional reaction to landscapes on site and higher satisfaction of visiting the park. Among the variables, visiting satisfaction, but not affective appraisals, played a statistically significant mediating role between place attachment and conservation intention. With a path coefficient of 0.86, conservation intention was highly affected by visiting satisfaction. These results suggest that the managers of National Parks should focus on increasing visiting satisfaction based on how visitors are emotionally bonded with their visiting places, in order to enhance the intentions to conserve the landscape of the visitors to National Parks.