Development and validation of a simple mineral dust source inventory suitable for modelling in North Central China

IEECAS SKLLQG

ESTIMATION OF THE RADIATION-INDUCED DAMAGE IN PTFE BY DEPRESSION OF THE MELTING AND CRYSTALLIZATION TEMPERATURES

The radiation induced depression of the melting and crystallization temperatures of PTFE irradiated at various temperatures followed by heat treatment at 380-degrees-C, and their relationship to structural changes, were investigated. The G(-units) values obtained in this work are different from those of samples which have not undergone heat treatment and seem to be more closely associated with radiation induced branched structures.

Hydrogeochemistry of formation water in relation to overpressures and fluid flow in the Qikou Depression of the Bohai bay basin, China

The Qikou Depression is the largest hydrocarbon bearing depression in the western part of the Bohai bay basin, dominated by fan delta and lacustrine strata with volcanic and volcaniclastic rocks. In this study, the formation pressures and hydrochemistry of the formation water in the Qikou depression are investigated. It is found that a significant overpressure occurs in the Dongying (Ed) Formation and the first member (Est), the second member (Es2), the third member (Es3) of the Shahejie Formation. The pressure coefficients commonly range from 1.2 to 1.6 with the highest pressure coefficient being 1.7. The analysis of hydrochemistry data shows that the whole depression is dominated by NaHCO3 water type. The concentration of total dissolved solid (TDS) ranges from 2.13 to 53.16 g/L and shows a distinct vertical variation of salinity and ion ratios. High salinity water (TDS> 10 g/L) occurs below a depth of 2500 m, which coincides with the presence of the overpressured system. However, the increasing trend of TDS is diminished below 3500 m because the generation of organic acids in Qikou Depression is inhibited in the presence of overpressure. The analysis of the relationship among different ions indicates that the present-day characteristics of the formation water result from the albitization of feldspar and the dissolution of sodium-rich silicate minerals and halite in the different hydrochemical and pressure systems. (C) 2009 Elsevier B.V. All rights reserved.

Inbreeding depression for various traits in two cultured populations of the American bay scallop, Argopecten irradians irradians Lamarck (1819) introduced into China

This paper examines the effect of inbreeding level of population on the magnitude of inbreeding depression expressed by comparing them between two cultured populations (A and B) in the hermaphroditic animal of the bay scallop Argopecten irradians irradians. Population A is expected to have less genetic variations and higher inbreeding level due to longer cultured history (20 generations) and less "ancestral" individuals (26 individuals) than population B due to shorter cultured history (4 generations) and more "ancestral" individuals (406 individuals). Two groups within each population were produced, one using self-fertilization and one using mass-mating within the same population. Selfed offspring (AS and BS) from two populations both had lower fitness components than their mass-mated counterparts (AM and BM) and exhibited inbreeding depression for all examined traits, e.g. lower hatching, less viability and slower growth, indicating that inbreeding depression is a common feature in this animal. Fitness components in all traits of offspring from population A significantly differed those from population B and the magnitude of inbreeding depression for all traits in population A with higher inbreeding level was significantly smaller than that in population B with lower inbreeding level, indicating that both fitness components and magnitude of inbreeding depression were significantly affected by inbreeding level of populations and genetic load harbored in population A may be partially purged through inbreeding. Moreover, the magnitude of inbreeding depression in the two populations both varied among traits and life history stages. The present results support the partial-dominance hypothesis of inbreeding depression. (C) 2008 Elsevier B.V. All rights reserved.

An inventory of forest relicts in the pastures of Southern Tibet (Xizang AR, China)

An inventory of isolated tree stands surrounded by desert pastures in Southern Tibet (A.R. Xizang, China) revealed more than 50 sites with vigorous trees of Juniperus convallium Rehder & E.H. Wilson and Juniperus tibetica Kom and additional more than 10 records where juniper trees had been destroyed between 1959-1976. The tree stands are not restricted to any specific habitat, and occur within an area stretching 650 km westwards from the current forest border of Southern Tibet. The trees are religious landmarks of the Tibetan Buddhists. The highest trees were found at an elevation of 4,860 m. Vegetation records, rainfall correlations and temperature data collected by local climate stations and successful reforestation trials since 1999 indicate that forest relicts fragmented through human interference could regenerate if current cattle grazing and deforestation practices are halted. The drought line of Juniperus forests in Southern Tibet is approximately 200-250 mm/a. A first pollen diagram from Lhasa shows forest decline associated with the presence of humans since at least 4,600 yr BP. The currently degraded commons developed in the last 600 yr. To date, no findings of remains of ancient forests in the Central Tibetan Highlands of the Changtang have been reported.

Depression of net ecosystem CO2 exchange in semi-arid Leymus chinensis steppe and alpine shrub

Uptake and release of carbon in grassland ecosystems is very critical to the global carbon balance and carbon storage. In this study, the dynamics of net ecosystem CO2 exchange (FNEE) of two grassland ecosystems were observed continuously using the eddy covariance technique during the growing season of 2003. One is the alpine shrub on the Tibet Plateau, and the other is the sem-arid Leymus chinensis steppe in Inner Mongolia of China. It was found that the FNEE of both ecosystems was significantly depressed under high solar radiation. Comprehensive analysis indicates that the depression of FNEE in the L. chinensis steppe was the results of decreased plant photosynthesis and increased ecosystem respiration (R-eco) under high temperature. Soil water stress in addition to the high atmospheric demand under the strong radiation was the primary factor limiting the stomatal conductance. In contrast, the depression of FNEE in the alpine shrub was closely related to the effects of temperature on both photosynthesis and ecosystem respiration, coupled with the reduction of plant photosynthesis due to partial stomatal closure under high temperature at mid-day. The R,c of the alpine shrub was sensitive to soil temperature during high turbulence (u* > 0.2 m s(-1)) but its FNEE decreased markedly when the temperature was higher than the optimal value of about 12 degrees C. Such low optimal temperature contrasted the optimal value (about 20 degrees C) for the steppe, and was likely due to the acclimation of most alpine plants to the long-term low temperature on the Tibet Plateau. We inferred that water stress was the primary factor causing depression of the FNEE in the semi-arid steppe ecosystem, while relative high temperature under strong solar radiation was the main reason for the decrease of FNEE in the alpine shrub. This study implies that different grassland ecosystems may respond differently to climate change in the future. (c) 2006 Elsevier B.V All rights reserved.

Photosynthetic depression in relation to plant architecture in two alpine herbaceous species

The Qinghai-Tibet Plateau is characterized by extremely high radiation, which may induce down-regulation of photosynthesis in plants living in this alpine ecosystem. To clarify whether photoinhibition occurs in the alpine environment and to discern its underlying mechanisms, we examined photosynthetic gas exchange and fluorescence emission in response to the changes in photosynthetic photon flux density (PPFD) and leaf temperature under natural regimes for two herbaceous species: prostrate Saussurea superba and erect-leaved Saussurea katochaete from altitude 3250 m on the Qinghai-Tibet Plateau. S. superba intercepted a higher maximum PPFD and experienced much higher leaf temperature than the erect-leaved S. katochaete. S. superba exhibited a much higher light saturation point for photosynthesis than S. katochaete. Under controlled conditions, the former species had higher CO2 uptake rates and neither species showed obvious photosynthetic down-regulation at high PPFD. Under natural environmental conditions, however, apparent photoinhibition, indicated by reduced electron transport rate (ETR), was evident at high PPFD for both species. After a night frost, the photochemistry of S. katochaete was depressed markedly in the early morning and recovered by mid-day. After a frost-free night, it was high in the morning and low at noon due to high radiation. S. superba did not respond to the night frost in terms of daytime photochemical pattern. In both species, photochemical depression was aggravated by high leaf temperature and the erect species was more sensitive to high temperature. This study suggests that the high radiation on the Qinghai-Tibet Plateau is likely to induce rapidly reversible photoinhibition, which is related closely to plant architecture. Photochemistry in the prostrate species seems able to tolerate higher PPFD, without obvious suppression, than the erect species. (C) 2003 Elsevier Science B.V. All rights reserved.

成就目标与心理健康的关系及相关因素的作用

The relationship between achievement goal and mental health, and the effect of the related factors Abstract Recently, adolescent’s mental health and depression problem have been widely concerned all over the world. Studies concerning it have been done from different perspectives. High school is the key period of adolescent’s physical and mental development, when they may have a high risk of mental conflicts, certain behavioral and emotional problems. Through questionnaire with high school students as subjects, this study examines achievement goal, self-concept, social comparison and the relationship between these factors and mental health. This study consists of three parts: 1) a preliminary exploration of the relationship between vocational school students’ achievement goal, self-concept and their mental health; 2) a revision of the simplified Chinese version for Dykman’ s goal Orientation Inventory; 3) a further discussion on the relationship between high school students’ achievement goal, self-concept, social comparison and depression. Major findings of this study are: 1. Dykman’s Goal Orientation Inventory is revised. This revised version, with high validity and reliability, conforms to Dykman’s theoretical assumptions and can be a convenient and effective measurement for achievement goal. 2. Self-concept and achievement goal of vocational school students can make a significant prediction of their mental health. Learning goal influences mental health through self-concept. 3. Achievement goal, self-concept and social comparison of high school students are closely related to their depression. 4. Self-concept and social comparison of high school students are the mediator variable between achievement goal and depression. The theoretical and practical implications of this study: 1. With the simplified Chinese version of Dykman’s Goal Orientation Inventory revised and used first in this study, its applicability is inspected and the conclusion drawn by Dykman on the prediction of achievement goal on depression is examined as well; on the basis of previous studies, a comprehensive and systematic study is done on how the factors work together to influence mental health(particularly depression). 2. This study enrichs the studies with high school students as subjects. It provides methods and basis for the theoretical studies and interference about high school students’ mental health education and depression problem.

中职生的成就动机与行为问题的关系

Achievement motive is human’s social motive. In some sense, one’s all-life achievements are decided by his/her achievement motive. By which we can conclude that achievement motive has close connection with individual emotional experience. People pursuing success experience more positive emotion and less negative one, and have good behavioral adaptability. This study aims at explore the relation between achievement motive and behavior problems in the secondary vocational education schools through questionaries (the achievement motivation scale, UCLA Loneliness Scale，State-Trait Anxiety Inventory，Center for Epidemiologic Studies depression Scale and middle school students'behavior questionnaire). There were 1005 students whose age ranged from 14to21 years completed the questionnaires. The main conclusions of this thesis are as follows: (1) Achievement motive of student in the secondary vocational education schools is significantly lower than that of students in the senior high school. (2) Students in the secondary vocational education schools show more obvious emotion and Externalizing behavior problems than those of the senior high schools. (3) Students’ motivation for pursuing success in the secondary vocational education schools has negative correlation with emotion and Externalizing behavior problem, while the motivation for avoiding failure has positive correlation with the emotion and Externalizing behavior problem. Achievement motivation has negative correlation with emotion and Externalizing behavior problem. (4) Students’ achievement motivation shows obvious gender difference in the secondary vocational education schools. The avoiding failure element shows upward trend with the grades increasing and the difference is obvious. While the students’ achievement motive in the secondary vocational education schools shows significantly downward trend with the grades increasing. Whether holding a post at school has influence on the students’ achievement motivation, and the difference is significant. (5) Students’ Externalizing behavior problem in the secondary vocational education schools shows obvious gender difference. Whether holding a post at school has influence on the students’ Externalizing behavior problem, and depression and loneliness, and the difference is significant. Key words: Students in the Secondary Vocational Education Schools, Achievement Motivation, Behavior Problem, Emotion Problem, Externalizing Behavior Problem (Note: In this study, the behavior problems include not only the externalizing behavior problems, but also emotion problems.)