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The same cumulative carbon emission reduction target can correspond to multiple emission reduction pathways. This study explores how different coal power transition pathways with the same cumulative emissions reductions impact the transition costs, by assessing the dynamic transition processes for coal plants adopting multiple mitigation technologies concurrently or sequentially, such as flexibility operation, biomass and coal co-firing, carbon capture and storage, and compulsory retirement. We develop a plant-level dynamic optimization model and apply it to China's 4200+ coal plants. We find that under deep decarbonization, the majority of Chinese coal plants retrofit with multiple technologies to reduce emissions and retire naturally at lower costs while contributing to grid stability. Optimizing the pathway can potentially save over 700 billion U.S. Dollars for achieving the same target or increase cumulative emissions reduction from 30% to 50% at no additional cost. This analysis can help inform a cost-effective coal phase-out under China's carbon neutrality., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Nucleic acid modifications play important roles in biological activities and disease occurrences, and have been considered as cancer biomarkers. Due to the relatively low amount of nucleic acid modifications in biological samples, it is necessary to develop sensitive and reliable qualitative and quantitative methods to reveal the content of any modifications. In this review, the key processes affecting the qualitative and quantitative analyses are discussed, such as sample digestion, nucleoside extraction, chemical labeling, chromatographic separation, mass spectrometry detection, and data processing. The improvement of the detection sensitivity and specificity of analytical methods based on mass spectrometry makes it possible to study low-abundance modifications and their biological functions. Some typical nucleic acid modifications and their potential as biomarkers are displayed, and efforts to improve diagnostic accuracy are discussed. Future perspectives are raised for this research field.

Mitigating greenhouse gas emissions is necessary to reduce the overall negative climate change impacts on crop yields and agricultural production. However, certain mitigation measures may generate unintended consequences to food availability and food access due to both land use competition and economic burden of mitigation. Integrated assessment models (IAM) are generally used to evaluate these policies; however, currently these models may not capture the importance of income and food prices for hunger and overall economic wellbeing. Here, we implement a measure of food security that captures the nutritional and economic aspects as the total expenditures on staple foods divided by income and weighted by total caloric consumption in an IAM, the global change analysis model (GCAM4.0). We then project consumer prices and our measure of food security along the shared socioeconomic pathways. Sustained economic growth underpins increases in caloric consumption and lowering expenditures on staple foods. Strict conservation policies affect food accessibility in a larger number of developing countries, whereas the negative effects of pricing terrestrial emissions are more concentrated on the poor in Sub-Saharan Africa, by substantially replacing their cropland with forests and affecting the production of key staples., Supplementary Information: The online version contains supplementary material available at 10.1007/s10669-022-09860-4., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Crown 2022.)

Clean air policies in China have substantially reduced particulate matter (PM 2.5 ) air pollution in recent years, primarily by curbing end-of-pipe emissions. However, reaching the level of the World Health Organization (WHO) guidelines may instead depend upon the air quality co-benefits of ambitious climate action. Here, we assess pathways of Chinese PM 2.5 air quality from 2015 to 2060 under a combination of scenarios that link global and Chinese climate mitigation pathways (i.e. global 2°C- and 1.5°C-pathways, National Determined Contributions (NDC) pledges and carbon neutrality goals) to local clean air policies. We find that China can achieve both its near-term climate goals (peak emissions) and PM 2.5 air quality annual standard (35 μg/m 3 ) by 2030 by fulfilling its NDC pledges and continuing air pollution control policies. However, the benefits of end-of-pipe control reductions are mostly exhausted by 2030, and reducing PM 2.5 exposure of the majority of the Chinese population to below 10 μg/m 3 by 2060 will likely require more ambitious climate mitigation efforts such as China's carbon neutrality goals and global 1.5°C-pathways. Our results thus highlight that China's carbon neutrality goals will play a critical role in reducing air pollution exposure to the level of the WHO guidelines and protecting public health., (© The Author(s) 2021. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

More than half of current coal power capacity is in China. A key strategy for meeting China's 2060 carbon neutrality goal and the global 1.5 °C climate goal is to rapidly shift away from unabated coal use. Here we detail how to structure a high-ambition coal phaseout in China while balancing multiple national needs. We evaluate the 1037 currently operating coal plants based on comprehensive technical, economic and environmental criteria and develop a metric for prioritizing plants for early retirement. We find that 18% of plants consistently score poorly across all three criteria and are thus low-hanging fruits for rapid retirement. We develop plant-by-plant phaseout strategies for each province by combining our retirement algorithm with an integrated assessment model. With rapid retirement of the low-hanging fruits, other existing plants can operate with a 20- or 30-year minimum lifetime and gradually reduced utilization to achieve the 1.5 °C or well-below 2 °C climate goals, respectively, with complete phaseout by 2045 and 2055.

A rapid transition away from unabated coal use is essential to fulfilling the Paris climate goals. However, many countries are actively building and operating coal power plants. Here we use plant-level data to specify alternative trajectories for coal technologies in an integrated assessment model. We then quantify cost-effective retirement pathways for global and country-level coal fleets to limit long-term temperature change. We present our results using a decision-relevant metric: the operational lifetime limit. Even if no new plants are built, the lifetimes of existing units are reduced to approximately 35 years in a well-below 2 °C scenario or 20 years in a 1.5 °C scenario. The risk of continued coal expansion, including the near-term growth permitted in some Nationally Determined Contributions (NDCs), is large. The lifetime limits for both 2 °C and 1.5 °C are reduced by 5 years if plants under construction come online and 10 years if all proposed projects are built.

The objective of this paper was to evaluate the effect of vanadium (V) in high-fat diets sourced from egg yolk on body weight gain, feed intake, blood characteristics and antioxidative status of Wistar rats. A total of 72 female Wistar rats were allocated according to a 2 × 4 factorial design throughout a 5-wk trial, including 2 levels of dietary fat (normal and high; ether extract 40.3 and 301.2 g/kg; fat sourced from egg yolk) and 4 levels of dietary V (0, 3, 15 and 30 mg/kg). Vanadium decreased ( P  ≤ 0.05) body weight gain (V at 30mg/kg during wk 1 and 2; V at 15 and 30 mg/kg during the overall phase), feed intake (V at 30 mg/kg during wk 3 and the overall phase; V at 15 and 30 mg/kg during wk 4), but increased the relative weight of liver (V at 30 mg/kg, P  ≤ 0.05). Moreover, increasing dietary V significantly increased ( P  ≤ 0.05) plasma aspartate aminotransferase, alanine aminotransferase and malondialdehyde levels and decreased triglyceride level, and V at 30 mg/kg in high-fat treatment had the highest or lowest values (interaction, P  ≤ 0.05). Under the same dietary V dose, V residual content in liver (dietary V at 15 and 30 mg/kg) and kidney (dietary V at 15 mg/kg) was higher in high-fat diet treatment compared with normal-fat diet treatment ( P  ≤ 0.05). In conclusion, it is suggested that V could decrease the body weight together with the feed intake, and the high fat could enhance oxidative stress induced by V of Wistar rats.

Research on the interaction between dietary vitamins and intestinal bacteria is poorly understood. To investigate the effect of dietary vitamins on the cecal bacterial communities, 2 bacterial 16S rRNA gene clone libraries were constructed from pooled PCR products obtained from the cecal digesta of 28-d broilers fed diets with vitamins (V) at the NRC level or with no vitamins (NV). The results showed that BW gain and average feed intake of V broilers was significantly higher (P < 0.01) than NV broilers, whereas the feed/gain ratio was significantly lower (P < 0.01) in V broilers. A total of 188 and 185 clones were sequenced for the NV and V broilers, respectively. Sequence identity criterion of 98% was used to assign sequences to operational taxonomic units (OTU). Clones from the NV group broilers were assigned to 14 OTU, with 33% clones affiliated with the genus Clostridium, 19% affiliated with the genera Escherichia/Shigella, 14% affiliated with the genus Bacteroides, and the remaining clones (34%) affiliated with 5 other bacterial genera (Faecalibacterium, Parasporobacterium, Ruminococcus, Streptococcus, and Subdoligranulum). Clones from the V group broilers were assigned to 23 OTU, with 46% of the clones affiliated with the genus Clostridium, 11% affiliated with the genus Fecalibacterium, and the remaining clones (43%) affiliated with 8 other genera (Anaerofilum, Lactobacillus, Anaerotruncus, Oscillibacter, Alistipes, Gracilibacter, Acetivibrio, and Haloplasma). Three OTU assigned to Clostridium, Faecalibacterium, and Ruminoccus were shared between the 2 libraries. Shannon diversity index showed the V broilers exhibited significantly higher bacterial diversity (P = 0.05), and Libshuff analysis indicated that the community structure between the 2 groups was significantly different (P < 0.0001). These results suggest that lack of dietary vitamins can increase the ratio of facultative pathogenic bacteria and decrease the diversity of bacteria in the cecum of broilers. Our results provide new leads for further investigations on the interaction between dietary vitamin additives and the gut health of broilers.