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Middle East respiratory syndrome coronavirus (MERS-CoV) is the causative agent of a severe respiratory disease with a high mortality of ~ 35%. The lack of approved treatments for MERS-CoV infection underscores the need for a user-friendly system for rapid drug screening. In this study, we constructed a MERS-CoV replicon containing the Renilla luciferase (Rluc) reporter gene and a stable luciferase replicon-carrying cell line. Using this cell line, we showed that MERS-CoV replication was inhibited by combined application of lopinavir and ritonavir, indicating that this cell line can be used to screen inhibitors of MERS-CoV replication. Importantly, the MERS-replicon cell line can be used for high-throughput screening of antiviral drugs without the need for live virus handling, providing an effective and safe tool for the discovery of antiviral drugs against MERS-CoV. 相似文献
884.
《Palaeoworld》2021,30(3):583-592
Palynological analyses in combination with radiocarbon dating on a Holocene borehole from the Lake Nanyi, Anhui Province, East China demonstrate a well-documented local vegetation evolution since 9000 cal BP, which is the first record of Holocene climate change and human impact in this region. Since 9000 cal BP a mixed evergreen and deciduous broad-leaved forest dominated by Cyclobalanopsis and Quercus developed in this area, indicating a warm climate condition with enhanced insolation. A mixed evergreen and deciduous broad-leaved forest was fully developed between 6600–4500 cal BP, which corresponds to the Holocene Climate Optimum with the strong influence of East Asian summer monsoon (EASM). After 3000 cal BP the broad-leaved forest decreased rapidly, while land herbs and ferns increased. It seems that the climate condition in East China was similar to the present after Holocene Climate Optimum. Pollen results show a potential interface between environment changes and human activities. Pollen diagram demonstrates that human impacts on the natural vegetation remained weak at the early stage but significantly enhanced upwards. The distinctive fluctuations of the pollen contents among AP (trees and shrubs), and the possible agriculture indicators might infer the potential human behaviors for environment changes. Due to the enlargement of organized farming and increase in population, natural forest was eventually replaced by farmland since 3000 cal BP. This study would increase our knowledge of Holocene vegetation transition related to the monsoon dynamics on a long timescale in East China and provide an environmental background for more detailed studies on cultural developments in the middle and lower reaches of the Yangtze River region. 相似文献
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886.
《L'Anthropologie》2021,125(5):102964
The aim of this paper is to present a review of current knowledge concerning the Paleolithic records and the related natural environmental setting in the Eurasian Far East and Hokkaido, located at the northern tip of the Japanese islands. At present, it is quite difficult to answer whether the archaic humans dispersed from Siberia and northern China across the Amur River basin and Sakhalin into Hokkaido or not, because there is no reliable evidence indicating the Lower and Middle Paleolithic in Hokkaido. We demonstrate that the Upper Paleolithic assemblages in Hokkaido can be divided into at least three phases such as the early Upper Paleolithic (EUP), the middle Upper Paleolithic (MUP), and the late Upper Paleolithic (LUP), based on a synthesis of available radiocarbon dates and the techno-typological characteristics of lithic assemblages. It is reasonable to suggest that the lithic assemblage from the Rubenosawa site, located in northern Hokkaido, and some of lithic assemblages at the transition from the Middle to Upper Paleolithic or the initial Upper Paleolithic (IUP) in Siberia share the relative similarities of techno-typological attributes in the reduction sequences, although the reliable radiocarbon dates have not been obtained from the Rubenosawa site unfortunately. Also, the emergence of microblade technology at the MUP in Hokkaido, such as represented by the microblade assemblage recovered from the Kashiwadai-1 site, central Hokkaido, indicates a close interaction between the Eurasian Far East and Hokkaido. As a result, the comparison of archaeological evidence in these regions provides us with a suggestion that the appearance and development of the Upper Paleolithic assemblages in Hokkaido were sometimes associated with the human dispersions and the mutual contacts crossing between the Eurasian Far East and Hokkaido. 相似文献
887.
In spite of their recognized importance as seed dispersers in other parts of the tropics, seed dispersal by fruit bats has received scant research attention in Africa. To evaluate the role of African fruit bats in seed dispersal, we studied fruits and seeds below 480 bat feeding roosts in the East Usambara Mountains of Tanzania. We compared these findings to those reported in other African localities to place our results in a broader context. We found 49 plant species dispersed by bats: 28 species, 18 genera, and one family are novel reports of bat dispersal in Africa. Approximately 20 percent of the submontane tree flora of the East Usambaras is bat‐dispersed, including both widespread and endemic trees. African fruit bats are important seed dispersers at our study site because they move seeds of dozens of species tens or hundreds of meters, even seeds that are too large to ingest (greater than 5 mm in length). Fruit bats are likely important seed dispersers in other Afrotropical forests, as bats elsewhere in Africa are known to consume 20 genera and 16 species of plants reported here. Insights from studying remains under bat feeding roosts offer a simple method to further document and substantially increase our understanding of the role of African fruit bats in seed dispersal. 相似文献
888.
Einhard Bezzel 《Zoology in the Middle East.》2013,59(1):24-26
Sagittal otoliths are widely used to determine taxon, age and size of the teleost fishes, and are useful tools for studies of prey-predator relationships, population dynamics and ichthyo-archaeology. They can also be used to estimate the size of the prey. We examined the relationships between otolith measurements (length, height and weight) and fish size (total length and weight) for two species of Argentinidae (Argentina sphyraena and Glossanodon leioglossus) from the Southern Aegean Sea, Turkey. Length, height and mass of sagittae were shown to be good indicators for the length and weight of fish in both species. Glossanodon leioglossus has relatively larger sagittae than Argentina sphyraena. Linear and exponential functions provided the best fit for relations between otolith and fish measurements. No significant differences were found between left and right otolith sizes. 相似文献
889.
Erdem Hızal 《Zoology in the Middle East.》2013,59(2):118-122
In a one-year study on the diet of the Long-eared Owl, Asio otus, in the area of Karap?nar in Central Anatolia, 5324 prey items were recovered from 3314 pellets collected at monthly intervals. At least 7 species of mammals belonging to Insectivora (Crocidura suaveolens) and Rodentia (Allactaga williamsi, Cricetulus migratorius, Meriones tristrami, Mescocricetus brandti, Microtus guentheri, M. sp., Mus macedonicus) were identified. Rodentia were dominant and contributed 93.8% of the number of prey items of the Long-eared Owl. Microtus guentheri accounted for 83.9% of the rodent remains. The diet pattern was more diverse in summer, when some 24% of the diet consisted of non-mammal prey items (birds, insects). 相似文献
890.
Abstract Foot-prints and direct observations showed that the Egyptian Mongoose is relatively common in the Çukurova region of southern Turkey. Droppings contained approx. 65% birds. 相似文献