Quaternary climatic changes have been recognized to influence the distribution patterns and evolutionary histories of extant organisms, but their effects on alpine species are not well understood. To investigate the Pleistocene climatic oscillations on the genetic structure of amphibians, we sequenced one mitochondrial and three nuclear DNA fragments in Nanorana parkeri, a frog endemic to the Tibetan Plateau, across its distribution range in the southern plateau. Mitochondrial cytochrome b (Cytb) and three nuclear genes (c-Myc2, Rhod, and Tyr) revealed two distinct lineages (i.e. the lineages East and West), which were strongly geographically structured. The split of the two divergent lineages was dated back earlier than the Middle Pleistocene, probably being associated with climatic and ecological factors. Species distribution modeling, together with the phylogeographic structuring, supported the hypothesis of multiple refugia for N. parkeri on the Tibetan Plateau during the Pleistocene glaciations, and suggested the Yarlung Zangbo valley and the Kyichu catchment to be the potential refugia. Our findings indicate that Pleistocene climatic changes have had a great impact on the evolution and demographic history of N. parkeri. Our study has important implications for conservation of this and other frog species in the Tibetan Plateau.
Introduction: Maternal 25-hydroxyvitamin D [25(OH)D] deficiency has a negative influence on the health of the mother and the developing fetus. The aim of this study was to assess serum 25(OH)D status and its relationship to virologic and biochemical parameters in pregnant women with chronic hepatitis B virus (HBV) infection. Methodology: Serum 25(OH)D levels among 142 pregnant women with chronic HBV infection and 251 healthy pregnant women were measured using enzyme-linked immunosorbent assay. Results: The mean ± SD values for serum 25(OH)D levels were 13.63 ± 5.5 ng/mL in healthy pregnant women and 12.05 ± 3.3 ng/mL in pregnant women with chronic HBV infection (p < 0.01). Serum 25(OH)D levels were associated with seasonal variation in healthy pregnant women (p = 0.01); however, similar results were not observed in pregnant women with chronic HBV infection (p = 0.10). Furthermore, multivariate analysis indicated that only ALT level was independently associated with severe vitamin D deficiency (p = 0.01). A significant positive correlation was found between serum 25(OH)D level and ALT level in pregnant women with chronic HBV infection (r = 0.32; p < 0.001). Conclusions: Vitamin D levels were lower in pregnant women with chronic HBV infection compared with healthy pregnant women. Vitamin D supplementation can be routinely recommended for pregnant women in China.
Interest is increasing among political scientists in leveraging the extensive information available in images. However, the challenge of interpreting these images lies in the need for specialized knowledge in computer vision and access to specialized hardware. As a result, image analysis has been limited to a relatively small group within the political science community. This landscape could potentially change thanks to the rise of large language models (LLMs). This paper aims to raise awareness of the feasibility of using Gemini for image content analysis. A retrospective analysis was conducted on a corpus of 688 images. Content reports were elicited from Gemini for each image and then manually evaluated by the authors. We find that Gemini is highly accurate in performing object detection, which is arguably the most common and fundamental task in image analysis for political scientists. Equally important, we show that it is easy to implement as the entire command consists of a single prompt in natural language; it is fast to run and should meet the time budget of most researchers; and it is free to use and does not require any specialized hardware. In addition, we illustrate how political scientists can leverage Gemini for other image understanding tasks, including face identification, sentiment analysis, and caption generation. Our findings suggest that Gemini and other similar LLMs have the potential to drastically stimulate and accelerate image research in political science and social sciences more broadly.
An up-to-date regional heating scheme will be discussed based on regenerative reheating electric boiler and ground source heat pump in this paper. Different from the current coal-fired boilers, central heating platform integrating the two systems can implement "electric power replacement" for regional central heating via dispatching and matching the corresponding data.
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