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1.
The Asian Tree Toad genus Pedostibes, as currently understood, exhibits a conspicuously disjunct distribution, posing several immediate questions relating to the biogeography and taxonomy of this poorly known group. The type species, P. tuberculosus and P. kempi, are known only from India, whereas P. hosii, P. rugosus, and P. everetti are restricted to Southeast Asia. Several studies have shown that these allopatric groups are polyphyletic, with the Indian Pedostibes embedded within a primarily South Asian clade of toads, containing the genera Adenomus, Xanthophryne, and Duttaphrynus. Southeast Asian Pedostibes on the other hand, are nested within a Southeast Asian clade, which is the sister lineage to the Southeast Asian river toad genus Phrynoidis. We demonstrate that Indian and Southeast Asian Pedostibes are not only allopatric and polyphyletic, but also exhibit significant differences in morphology and reproductive mode, indicating that the Southeast Asian species’ are not congeneric with the true Pedostibes of India. As a taxonomic solution, we describe a new genus, Rentapia
gen. nov. to accommodate the Southeast Asian species. 相似文献
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S. Rai Karamjit 《Journal of genetics》1999,78(3):163-169
Beginning in the mid-1950s, much progress has been made in studying various aspects of the genetics of mosquitoes, particularly involving several species of three principal genera,Aedes, Culex andAnopheles, that transmit important human diseases. Here I discuss selected areas of research involving formal genetics; genome structure, organization and evolution at the interspecific and intraspecific level; and evolutionary genetics of theAedes scutellaris group. Information and insights gained from in-depth analyses of these areas, particularly transmission genetics, cytogenetics and genetics of chromosomal rearrangements, and of mutagen-induced sexual sterility, have proved invaluable for the development of the theory and evaluation of feasibility of genetic control of natural populations. As a result, mosquitoes represent some of the best studied taxa at various levels of genetic organization. Recent developments in molecular genetics offer exciting possibilities for extension of these concepts. 相似文献
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Merih Anil 《Dialectical Anthropology》2005,29(3-4):453-470
Since the beginning of the 1990s, Germany has been taking controversial policy measures that had been quite unimaginable, even in the 1980s. On the one hand, regulations for asylum seekers and ethnic Germans have gradually become restrictive in nature. On the other hand, changes to the Citizenship and Nationality Law of 1913 (Reichs und Staatsangehörigkeitsgesetz) and the Alien Act of 1965 (Ausländergesetz) have dramatically altered the naturalization process. Before the passage of the new German citizenship law in 1999, the acquisition of citizenship in Germany was solely based on the principle of descent (jus sanguinis). This paper attempts to explain why German government altered its citizenship policy and introduced birthright citizenship. It reviews the post-war contextual factors that have shaped the debate on citizenship and asks whether it is external or internal factors, that is international-level norms and institutions or domestic politics, that led to the change. If domestic politics can fully explain the adoption of the new citizenship law, what domestic forces played an important role? Was state action taken in the name of protecting “the national interest” or was it party politics? What role did societal forces play in the making of new citizenship policy? Did the act seek to mitigate anti-foreigner sentiment growing in Germany since the 1990s? Using archival and documentary research and secondary data on socio-economic and demographic trends in Germany, this paper concludes that domestic politics explain the changes in the citizenship law. I argue that granting and withholding national citizenship, including birthright citizenship, is exclusively in the hands of a nation state. Considering a purely ethnocultural understanding of nation-hood now includes legal and territorial components, the new German citizenship law is a major reform at the both theoretical and conceptual level. However, the practical consequences of the new naturalization process remain to be seen. The main question for the future research agenda is whether the new naturalization and citizenship laws will bring full integration of foreigners living in German society. 相似文献
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Audesh Bhat Anil Koul Ekta Rai Swarkar Sharma M. K. Dhar R. N. K. Bamezai 《Human genetics》2008,123(1):115
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S. C. Rai 《Biometrical journal. Biometrische Zeitschrift》1987,29(4):449-454
A multi-sample slippage test based on ordered observations has been given. The test statistic is based on the sum of ranks of the sample. The probability distribution of the test statistic has been worked out for small sample and it turns out to be chi-square distribution for large sample. The analytical procedure has been explained by a numerical example. 相似文献
8.
Yiwen Sun Zexuan Zhu Siping Chen Jega Balakrishnan Derek Abbott Anil T. Ahuja Emma Pickwell-MacPherson 《PloS one》2012,7(11)
The GP2 peptide is derived from the Human Epidermal growth factor Receptor 2 (HER2/nue), a marker protein for breast cancer present in saliva. In this paper we study the temperature dependent behavior of hydrated GP2 at terahertz frequencies and find that the peptide undergoes a dynamic transition between 200 and 220 K. By fitting suitable molecular models to the frequency response we determine the molecular processes involved above and below the transition temperature (T
D). In particular, we show that below T
D the dynamic transition is dominated by a simple harmonic vibration with a slow and temperature dependent relaxation time constant and that above T
D, the dynamic behavior is governed by two oscillators, one of which has a fast and temperature independent relaxation time constant and the other of which is a heavily damped oscillator with a slow and temperature dependent time constant. Furthermore a red shifting of the characteristic frequency of the damped oscillator was observed, confirming the presence of a non-harmonic vibration potential. Our measurements and modeling of GP2 highlight the unique capabilities of THz spectroscopy for protein characterization. 相似文献
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