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Meadow degradation is often accompanied by significant changes in nitrogen (N)-cycling and nitrous oxide ([N.sub.2]O) emission potential, and leads to challenges in meadow management. However, the mechanisms of soil N-cycling and [N.sub.2]O emissions remain poorly understood, especially in alpine ecosystems. In this study, we investigated the soil N-cycling process in four alpine meadows on the Tibetan Plateau along a degradation gradient using real-time quantitative polymerase chain reaction and amplicon sequencing to elucidate the mechanisms. Compared to non-degraded meadows, meadow degradation reduced [N.sub.2]O emissions by 38.5-140.2%. Meadow degradation reduced the abundance of amoA of ammonia-oxidising archaea (AOA) and ammonia-oxidising bacteria (AOB), whereas light and moderate degradation increased the abundance of genes nirS, nirK, and nosZ. Lightly degraded meadow exhibited the highest a-diversity of both nitrifiers and denitrifiers, but this higher diversity was not accompanied by higher [N.sub.2]O emissions, with only 32.3% of the microbial taxa identified as predictors of [N.sub.2]O emissions, suggesting that functional redundancy exists in the N-cycling process in meadow ecosystems. Nitrosospira and Mesorhizobium from the AOB and nirK communities, respectively, were identified as the key taxa that may contribute to [N.sub.2]O emissions. Soil properties, especially N reaction substrates, including ammonium-N, nitrate-N, dissolved organic N, and total N, were the primary drivers for [N.sub.2]O emissions via mediation of the N-cycling community, especially nitrifiers. Our results emphasised the importance of environmental factors in shaping nitrifying, denitrifying, and [N.sub.2]O emissions, providing insights for the restoration of degraded meadow ecosystems. Keywords: alpine meadow, denitrification, functional genes, functional microbial diversity, meadow degradation gradient, [N.sub.2]O emissions, N-cycling, nitrification, partial least squares path model., Introduction Grasslands account for approximately one-fourth to one-third of the terrestrial surface of the earth, and support several functions such as carbon sequestration, animal husbandry, and support for the survival [...]

Drought has broad and deep influences on ecosystem dynamics and functions, particularly considering the lagged and cumulative effects of drought. Yet the individual role of climate variables in mediating such drought effects on vegetation remains largely unknown. Based on the Normalized Difference Vegetation Index (NDVI) and the standard precipitation evapotranspiration index (SPEI), here, we investigated the patterns and mechanisms of drought effects on alpine grasslands in the Qinghai–Tibetan Plateau (QTP) from 1982 to 2015. Drought imposed widespread lagged and cumulative impacts on alpine grasslands with notable spatial heterogeneity, showing that the southwestern and northeastern parts of the plateau were more sensitive and responded quickly to drought. Further, drought effects showed an evident elevation dependence across different grassland types, which could be explained by altitudinal shifts in climatic factors, including temperature and precipitation. Precipitation was the dominant factor in drought effects on alpine meadows, while temperature dominated the drought impacts on the alpine steppes. Such a divergent dominant factor implied that there would be different vegetation responses to future climate change among diverse types of alpine grasslands. To maintain the sustainability of alpine grassland, more effort should be applied to alpine steppes regarding pasture management, particularly in response to extreme drought due to warmer climates in the future. [ABSTRACT FROM AUTHOR]

Understanding the roles of core bacterial taxa in forage production is crucial for developing sustainable fertilization practices that enhance the soil bacteria and forage yield. This study aims to investigate the impact of different fertilization regimes on soil bacterial community structure and function, with a particular focus on the role of core bacterial taxa in contributing to soil nutrient content and enhancing forage yield. Field experiments and high-throughput sequencing techniques were used to analyze the soil bacterial community structure and function under various fertilization regimes, including six treatments, control with no amendment (CK), double the standard rate of organic manure (T01), the standard rate of organic manure with nitrogen input equal to T04 (T02), half the standard rate of inorganic fertilizer plus half the standard rate of organic manure (T03), the standard rate of inorganic fertilizer reflecting local practice (T04), and double the standard rate of inorganic fertilizer (T05). The results demonstrated that organic manure treatments, particularly T01, significantly increased the forage yield and the diversity of core bacterial taxa. Core taxa from the Actinomycetota, Alphaproteobacteria, and Gammaproteobacteria classes were crucial in enhancing the soil nutrient content, directly correlating with forage yield. Fertilization significantly influenced functions relating to carbon and nitrogen cycling, with core taxa playing central roles. The diversity of core microbiota and soil nutrient levels were key determinants of forage yield variations across treatments. These findings underscore the critical role of core bacterial taxa in agroecosystem productivity and advocate for their consideration in fertilization strategies to optimize forage yield, supporting the shift towards sustainable agricultural practices. [ABSTRACT FROM AUTHOR]

With global climate change leading to increasing intensity and frequency of droughts, as well as the growing problem of soil salinization, these factors significantly affect crop growth, yield, and resilience to adversity. Oats are a cereal widely grown in temperate regions and are rich in nutritive value; however, the scientific literature on the response of oat to drought and salt stress has not yet been analyzed in detail. This study comprehensively analyzed the response of oat to drought stress and salt stress using data from the Web of Science core database and bibliometric methods with R (version4.3.1), VOSviewer (version 1.6.19), and Citespace (version6.3.1.0) software. The number of publications shows an increasing trend in drought stress and salt stress in oat over the past 30 years. In the field of drought-stress research, China, the United States, and Canada lead in terms of literature publication, with the most academic achievements being from China Agricultural University and Canadian Agricultural Food University. The journal with the highest number of published papers is Field Crops Research. Oat research primarily focuses on growth, yield, physiological and biochemical responses, and strategies for improving drought resistance. Screening of drought-tolerant genotypes and transformation of drought-tolerant genes may be key directions for future oat drought research. In the field of salt-stress research, contributions from China, the United States, and India stand out, with the Chinese Academy of Agricultural Sciences and Inner Mongolia Agricultural University producing the most significant research results. The largest number of published articles has been found in the Physiologia Plantarum journal. Current oat salt-stress research primarily covers growth, physiological and biochemical responses, and salt-tolerance mechanisms. It is expected that future oat salt research will focus more on physiological and biochemical responses, as well as gene-editing techniques. Despite achievements under single-stress conditions, combined drought and salt-stress effects on oat remain understudied, necessitating future research on their interaction at various biological levels. The purpose of this study is to provide potential theoretical directions for oat research on drought and salt stress. [ABSTRACT FROM AUTHOR]

Despite its rarity, insulinoma is the most common type of pancreatic endocrine neoplasm, with an occurrence of 1 to 5 per million per year in the population. Surgical resection or enucleation is the first line of curative treatment choice for insulinoma. Eight patients with symptomatic insulinomas treated by radiofrequency ablation have been described since 2009. In the past two years, we treated two patients with symptomatic insulinomas (one in the pancreatic tail and the other in the pancreatic neck) successfully using laparoscopic radiofrequency ablation. Both patients achieved complete elimination without any significant complications. Our study suggests laparoscopic radiofrequency ablation could be developed as a safe and effective alternative treatment to surgery for the patients with insulinomas who refuse or are not eligible for surgery.

Drought and poor soil quality are the main characteristics of extreme environments in arctic–alpine areas. Understanding how herbaceous plants in alpine grasslands maintain the normal supply and utilisation of nutrients under different rainfall conditions is key to maintaining population stability. In the present study, the native plants Poa crymophila and Stipa purpurea of the Qinghai–Tibet Plateau were used to conduct a controlled experiment involving water and fertiliser to analyse their physiological responses in terms of nutrient uptake and utilisation. The results showed that decreased soil moisture increased proline and non-structural carbohydrates in P. crymophila, mainly accumulating in the leaves and stems. Nitrogen (N) addition promoted proline accumulation, whereas nonstructural carbohydrate content decreased. However, the proline and non-structural carbohydrate contents of S. purpurea were less affected by water and fertiliser. Additionally, drought restricted rhizospheric and non-rhizospheric alkaline-hydrolysed N release, increased rapidly available phosphorus (RAP) content in rhizospheric soil, limited root growth, and reduced surface area, root length, and root volume. Both aboveground and underground N fertiliser utilisation rates decreased. Under well-hydrated conditions (WH), high N levels increased rhizospheric alkaline-hydrolysed N and urease activity while inhibiting RAP and activity of alkaline phosphatase contents, thereby limiting root growth and reducing N fertiliser utilisation. The results indicate that both plant species have relatively low overall nutrient requirements that are limited mainly by water availability. The addition of low amounts of fertiliser is beneficial for nutrient release and utilisation, improving their adaptability to arctic–alpine environments and their suitability and superiority in the community. This study has significant implications for nutrient management and ecological restoration measures in arctic–alpine grasslands. [ABSTRACT FROM AUTHOR]