144 resultados para 322-C0011B
Resumo:
Background and Aims It is an enduring question as to the mechanisms leading to the high diversity and the processes producing endemics with unusual morphologies in the Himalayan alpine region. In the present study, the phylogenetic relationships and origins of three such endemic genera were analysed, Dolomiaea, Diplazoptilon and Xanthopappus, all in the tribe Cardueae of Asteraceae.Methods The nuclear rDNA internal transcribed spacer (ITS) and plastid trnL-F and psbA-trnH regions of these three genera were sequenced. The same regions for other related genera in Cardueae were also sequenced or downloaded from GenBank. Phylogenetic trees were constructed from individual and combined data sets of the three types of sequences using maximum parsimony, maximum likelihood and Bayesian analyses.Key Results The phylogenetic tree obtained allowed earlier hypotheses concerning the relationships of these three endemic genera based on gross morphology to be rejected. Frolovia and Saussurea costus were deeply nested within Dolomiaea, and the strong statistical support for the Dolomiaea-Frolovia clade suggested that circumscription of Dolomiaea should be more broadly redefined. Diplazoptilon was resolved as sister to Himalaiella, and these two together are sister to Lipschitziella. The clade comprising these three genera is sister to Jurinea, and together these four genera are sister to the Dolomiaea-Frolovia clade. Xanthopappus, previously hypothesized to be closely related to Carduus, was found to be nested within a well-supported but not fully resolved Onopordum group with Alfredia, Ancathia, Lamyropappus, Olgaea, Synurus and Syreitschikovia, rather than the Cardinis group. The crude dating based on ITS sequence divergence revealed that the divergence time of Dolomiaea-Frolovia from its sister group probably occurred 13.6-12.2 million years ago (Ma), and the divergence times of the other two genera, Xanthopappus and Diplazoptilon, from their close relatives around 5.7-4.7 Ma and 2.0-1.6 Ma, respectively.Conclusions The findings provide an improved understanding of the intergeneric relationships in Cardueae. The crude calibration of lineages indicates that the uplifts of the Qiinghai -Tibetan Plateau since the Miocene might have served as a continuous stimulus for the production of these morphologically aberrant endemic elements of the Himalayan flora.
Resumo:
红山铜矿床位于三江地区义敦岛弧南端的中甸弧,是在晚三叠世甘孜-理塘洋盆向西俯冲过程中形成的一个中型规模的矽卡岩矿床。通常,矽卡岩体就是铜矿体或铜矿化体,主要呈似层状、层状、脉状及透镜体状产于大理岩与角岩接触带或局部在角岩中,未见其与侵入岩直接接触。通过对不同成矿阶段所形成的石榴石、磁铁矿、磁黄铁矿、黄铁矿、黄铜矿、方解石等典型矿物以及大理岩的稳定同位素特征研究,发现矽卡岩的最主要组成矿物石榴石的δ^18OSMOW范围为6.2—8.3‰,反映了矽卡岩可能直接继承隐伏斑岩体的氧同位素组成。根据磁铁矿的氧同位素组成(5.5—7.1‰)所计算的磁铁矿化阶段成矿流体的δ^18OSMOW为13.1—14.7‰(400℃)或12.5—14.1%。(500℃),暗示有富集δ^18O的CO2溶入到成矿流体中。硫化物的δ^34SCDT范围4.45—6.20‰,说明矿床具有高度均一的硫源,并且在硫化物的结晶沉淀过程中,流体中硫同位素分馏很弱。由此推测主成矿期成矿流体的δ^34S∑S为5.6±0.6‰。矿床中的大理岩的δ^13CPDB为2.0—2.2‰,δ^18OSMOW为24.0—24.8‰,说明大理岩是由海相碳酸盐岩经重结晶作用而成。成矿晚期阶段形成的方解石脉的δ^13CPDB范围是-2.4—1.7‰,δ^18OSMOW范围是16.3—22.4‰,表明其C和O主要来源于大理岩。总之,我们推测红山矽卡岩很可能主要是由中酸性岩浆浅成侵位时局部同化碳酸盐围岩所形成的一种富含钙质成分的次生岩浆就位于碎屑岩与碳酸盐岩之间的构造薄弱带冷凝固结而成,矽卡岩型矿化与深部斑岩型矿化具有共同的成矿物质和成矿流体来源。
Resumo:
In China, orgnizational change and downsizing are the primary topics studied in I/O psychology and Human Resource Management. Due to the great need in reality, both theorists and practitioners raised the same questions: Does downsizing increase the organizational performance? What is the relationship between organizational downsizing strategies and survivors' psychological reations? Which factors influence managers' downsizing decision-making most? How can managers manage the process successfully? The purpose of this study is trying to answer these questions, and then to establish the downsizing decision-making model of China's SOE (State owned enterprise) managers. The hypothetical model of SOE managers' downsizing decision-making was put forward, based on a tremendous amount of literature on downsizing decision-making, especially on the downsizing decision-making model built by B. Shaw, and also based on the results of the interviews conducted to the SOE managers who have the downsizing decision-making experiences. In order to test and verify the model, 322 SOE managers were investigated by a questionnaire study. And the statistic results supported the hypothetical downsizing decision-making model. Further, 259 survivors (those who are still working in the SOEs) from 7 downsized SOEs and 1 non-downsizing SOE, were also investigated by a questionnaire study. The statistic results also supported the hypothetical downsizing decision-making model. A subsequent case study was performed upon one downsized SOE; and a deliberate focus group interview study within 6 SOE mangers from another downsized SOE was also conducted. Both fundings from the two studies surported the hypothetical model again. Thus, China's SOE managers' downsizing decision-making model was established. This China's SOE managers' downsizing decision-making model suggests the following: Firstly, the characteristics of managers'downsizing decision-making were the center of the model. Those characteristics displayed during the process of the downsizing decision planning, the participation of downsizing decision-making and the communication concerning downsizing events, were influenced by managers' sense of crisis, controlling factors out of the organization and the managing experience within it. Especially, the latter two factors were more important. Secondly, in downsizing decision-making problems, the perceived crisis of China's SOE managers was mainly influenced by the outer factors, esp. the controlling factors from the government or the high authorities, but not by the inner factors including manufacturing management, HRM skills and organizational competition strategies. Thirdly, survivors'psychological reactions (including job satisfaction, job motivation, team working cooperation, etc) were mainly influenced by the characteristics of the managers' downsizing decision-making, at the same time, also by the outer factors (including controlling and social security factors) and the inner factors (including competition strategy and HRM skills). Finally, according to the model and the results from this study, the conclusions were reached in the followings: The stronger the controlling effort upon the SOE managers, the worse the effect displayed during the downsizing process. And in order to improve the effect and quality of downsizing decision-making, SOE managers need a lot of training to ameliorate their competencies such as competition strategies and HRM skills.
Resumo:
A theoretical method to calculate multidimensional Franck-Condon factors including Duschinsky effects is described and used to simulate the photoelectron spectrum of the anion SO. Geometry optimizations and harmonic vibrational frequency calculations have been performed on the XA(1) state of SO2 and (XB1)-B-2 state of SO2. Franck-Condon analyses and spectral simulation were carried out on the first photoelectron band of SO2. The theoretical spectra obtained by employing CCSD(T)/6-31 I+G(2d,p) values are in excellent agreement with the experiment. In addition, the equilibrium geometric parameters, r(c)(OS) = 0.1508 +/- 0.0005 nm and theta(e)(O-S-0) = 113.5 +/- 0.5 degrees, of the (XB1)-B-2 state of SO2, are derived by employing an iterative Franck-Condon analysis procedure in the spectral simulation. (c) 2005 Elsevier B.V. All rights reserved.