Practical guidelines and recent advances in the Itrax XRF core-scanning procedure

XRF core scanning has evolved to become a standard analytical technique for the rapid assessment of elemental, density and textural variations in a wide range of sediments and other materials, with applications ranging from palaeoceanography, paleoclimatology, geology, and environmental forensics to environmental protection. In general, scanning provides rapid, non-destructive acquisition of elemental and textural variations at sub-millimetre resolution for a wide range of materials. Numerous procedural adaptations have been developed for the growing number of applications, such as analyses of unconsolidated, water-rich sediments, powdered soil samples, or resin bags. Here, practical expertise and guidance from the Itrax community, gained over 15 years, is presented that should provide insights for new and experienced users

Origin of Minerals and Elements in the Late Permian Coal Seams of the Shiping Mine, Sichuan, Southwestern China

Volcanic layers in coal seams in southwestern China coalfields have received much attention given their significance in coal geology studies and their potential economic value. In this study, the mineralogical and geochemical compositions of C19 and C25 coal seams were examined, and the following findings were obtained. (1) Clay minerals in sample C19-r are argillized, and sedimentary layering is not observed. The acicular idiomorphic crystals of apatite and the phenocrysts of Ti-augite coexisting with magnetite in roof sample C19-r are common minerals in basaltic rock. The rare earth elements (REE) distribution pattern of C19-r, which is characterized by positive Eu anomalies and M-REE enrichment, is the same as that of high-Ti basalt. The concentrations of Ti, V, Co, Cr, Ni, Cu, Zn, Nb, Ta, Zr, and Hf in C19-r are closer to those of high-Ti basalt. In conclusion, roof sample C19-r consists of tuffaceous clay, probably with a high-Ti mafic magma source. (2) The geochemical characteristics of the C25 coals are same as those reported for coal affected by alkali volcanic ash, enrichment in Nb, Ta, Zr, Hf, and REE, causing the C25 minable coal seams to have higher potential value. Such a vertical study of coals and host rocks could provide more information for coal-forming depositional environment analysis, for identification of volcanic eruption time and magma intrusion, and for facilitating stratigraphic subdivision and correlation

Agroecosystem composition and landscape ecological risk evolution of rice terraces in the southern mountains, China

Mountain rice terrace agriculture is a critical land use practice in southern China. Analyzing the vertical structure of rice terraces systems and the coupled evolution of their human-land relationship from a mountainous stereoscopic perspective is significant to regional resource use and sustainable agricultural development. This study took the Xijiang Township and Jiabang Township in the mountainous area of Southwest China as the research object, based on the unique rice farming environment in the mountainous region, to divide the typical types of the four-element isomorphic (FEI) of the regional forest, village, river, and rice terraces from the perspective of vertical differentiation. The spatiotemporal evolution characteristics of rice terraces based on the view of the social-ecological system were explored by using the land use data of Jiabang Township from 1962 (1977 in Xijiang Township) to 2020, and methods such as mathematical statistics, sample transect analysis. The ecological risk model was also employed to analyze the spatiotemporal variation characteristics and landscape stability of ecological risk in mountain rice terraces systems. The study showed that: (1) The rice terraces showed the “forest-terraces-village-river” (F-T-V-R), “forest-village-terraces-river” (F-V-T-R), and “forest-terraces-village-terraces-river” (F-T-V-T-R), and the rice terraces in each differentiation type experienced a continuous evolutionary feature of “development-stabilization-local shrinkage and shifted.” (2) The mixed production trend of “main rice and the auxiliary dry land” in the rice terraces landscape was gradually highlighted, and the degree of landscape abandonment and fragmentation was deepened, and the “F-T-V-T-R” structure had the highest landscape stability in long-term development. (3) The ecological risks of each landscape type showed the characteristics of “increase-stabilization-decrease” in different time series evolution. (4) Although the “F-T-V-T-R” landscape types in the two areas were at a high-risk level in the long term, the long-term changes are less fluctuating, and the landscape security stability is the highest. The research results comprehensively reflected the spatiotemporal evolution characteristics of the landscape spatial pattern of rice terraces, and revealed the reflection of the FEI vertical differentiation structure on the regional social ecosystem and human-land relationship, which can help us to promote the optimal utilization of traditional rice terraces resources in the mountains and promote the sustainable development of rice agriculture

Transformation and degradation of metal halide perovskites induced by energetic electrons and their practical implications

10.1088/2399-1984/ac0c24Nano Futures53032001-03200

Effects of landscape patterns and their changes on ecosystem health under different topographic gradients: A case study of the Miaoling Mountains in southern China

Ecosystem health is an essential characterization of landscape pattern ecological effects, and refined analysis of the variability of landscape pattern changes on ecosystem health in mountainous areas is of great significance for the synergistic development of the mountainous Man-Earth systems. This study constructed a research framework for the ecological effects of landscape patterns based on the theory of landscape ecology and topographic gradient. Taking the Miaoling Mountains in China as an example, used spatial analysis techniques to analyze the process of landscape pattern changes from 2000 to 2020 and detected the response of ecosystem health to the changes in the landscape pattern by using rank correlation analysis. The study showed that: (1) The landscape pattern of the study area changed significantly during the study period, especially in the geographically disadvantaged areas, mainly showing an expansion of the landscape scale of the forestland and a shift of the landscape dominance of the farmland to the gently sloping lowland areas. (2) The ecosystem was at an average health level (mean ecosystem health index (EHI) = 0.58), and the EHI showed a “V” shape dynamic since 2000. (3) The changes in landscape patterns significantly impacted ecosystem health, and the effect varies considerably across topographic gradients, with the landscape shape index (LSI) and Shannon diversity index (SHDI) being the main factors influencing ecosystem health. This study emphasizes the importance of implementing regional and systemic landscape management strategies in the Miaoling Mountains according to local conditions and suggests four rational strategies, including zoning controls around the forestland and farmland. The study's results provide a valuable reference for defining key conservation areas and control indicators for regional ecological restoration in the Miaoling Mountains and for landscape management in mountainous regions worldwide

Analysis of the Land Use Dynamics of Different Rural Settlement Types in the Karst Trough Valleys of Southwest China

Rural settlements are the basic spatial units of rural geography research, and it is essential to explore the dynamic changes in land use on a rural settlement scale to promote the development of the rural revitalization strategy. The study took different rural settlement types in karst trough valleys as examples and applied geographic information mapping trajectory models, buffer zone spatial analysis, the nearest neighbor index, and other research methods. We explored the land use dynamic change in the buffer zone of different settlement types in the karst trough valley from 1964 to 2021 in the long time series and micro-spatial dimensions. We analyzed the homogeneity, variability, and coupling characteristics of land use evolution in typical settlements. The results indicate the following: (1) From 1964 to 2021, the karst trough valley settlements as a whole showed an aggregation state, and the settlements could be classified into four categories: expanding settlements (ES), atrophic settlements (AS), balancing rural settlements (BS), and decreasing settlements (DS) according to the settlement life cycle theory and settlement development index measurement. (2) Different expansion and shrinkage of land use buffer changes exist for different settlement types. The closer the ES is to the location of the settlement center, the richer the land use type; the further the AS from the settlement center, the richer the land use type; the BS is not affected by the distance; and the DS settlement shows dynamic changes. (3) Land use dynamic change in settlements is driven by multiple integrated factors, and there is variability in the driving factors of different settlement types. (4) In this paper, through a case study, we propose the research idea that land use change (LUCC) reflects land use transformation (LUT) in different rural settlement types from a settlement-scale perspective, and land use transformation further causes the development of rural settlement transformation (RUT). Our study revealed the LUCC—LUT—RUT interaction feedback mechanism of karst trough valley settlements in Southwest China. This study aims to enrich the theoretical research framework of rural transformation at the settlement scale, on the one hand, and to provide case studies for developing countries with karstic mountain valley landscapes, such as China, on the other

Analysis of the Land Use Dynamics of Different Rural Settlement Types in the Karst Trough Valleys of Southwest China

Rural settlements are the basic spatial units of rural geography research, and it is essential to explore the dynamic changes in land use on a rural settlement scale to promote the development of the rural revitalization strategy. The study took different rural settlement types in karst trough valleys as examples and applied geographic information mapping trajectory models, buffer zone spatial analysis, the nearest neighbor index, and other research methods. We explored the land use dynamic change in the buffer zone of different settlement types in the karst trough valley from 1964 to 2021 in the long time series and micro-spatial dimensions. We analyzed the homogeneity, variability, and coupling characteristics of land use evolution in typical settlements. The results indicate the following: (1) From 1964 to 2021, the karst trough valley settlements as a whole showed an aggregation state, and the settlements could be classified into four categories: expanding settlements (ES), atrophic settlements (AS), balancing rural settlements (BS), and decreasing settlements (DS) according to the settlement life cycle theory and settlement development index measurement. (2) Different expansion and shrinkage of land use buffer changes exist for different settlement types. The closer the ES is to the location of the settlement center, the richer the land use type; the further the AS from the settlement center, the richer the land use type; the BS is not affected by the distance; and the DS settlement shows dynamic changes. (3) Land use dynamic change in settlements is driven by multiple integrated factors, and there is variability in the driving factors of different settlement types. (4) In this paper, through a case study, we propose the research idea that land use change (LUCC) reflects land use transformation (LUT) in different rural settlement types from a settlement-scale perspective, and land use transformation further causes the development of rural settlement transformation (RUT). Our study revealed the LUCC—LUT—RUT interaction feedback mechanism of karst trough valley settlements in Southwest China. This study aims to enrich the theoretical research framework of rural transformation at the settlement scale, on the one hand, and to provide case studies for developing countries with karstic mountain valley landscapes, such as China, on the other

Assessment of Sustainable Development of Rural Settlements in Mountainous Areas: A Case Study of the Miaoling Mountains in Southwestern China

As a model based on the harmonious development of society, economy, population, and resources, sustainable development is an essential driving force for a country’s social and economic development. The countryside is an important part of the country, and its sustainable development has been given attention, but existing research lacks a focus on the sustainable development of rural settlements in mountainous areas. In this paper, the rural settlements in the Miaoling Mountains of China are taken as the research object, a geographic detector is used to determine the weight of rural settlement sustainable development factors, a rural settlement sustainable development model is constructed, and a local spatial autocorrelation method is used to quantitatively analyse the level of sustainable development of the rural settlements and the influencing factors related to both the natural environment and socio-economic levels. The results show that (1) 78% of rural settlements in the Miaoling Mountains have a medium to low level of sustainable development and are weak in overall sustainability. (2) The spatial differentiation of the sustainable development levels of rural settlements in the Miaoling Mountains are apparent, and the high sustainable development level settlements are mainly distributed around the urban areas. In contrast, the low sustainable development level settlements are scattered. (3) The level of sustainable development is positively correlated spatially with gross domestic product (GDP), arable land, elevation, normalised difference vegetation index (NDVI), water systems, and roads, and negatively correlated spatially with slope. Of these, GDP, arable land, and elevation have a more substantial influence on the level of sustainability of rural settlements. According to the local autocorrelation analysis, the positively correlated settlement types are mainly clustered in distribution, while the negatively correlated settlement types are sporadic

Augmentation of Antitumor Immunity by Human and Mouse CAR T Cells Secreting IL-18

The effects of transgenically encoded human and mouse IL-18 on T cell proliferation and its application in boosting chimeric antigen receptor (CAR) T cells are presented. Robust enhancement of proliferation of IL-18-secreting human T cells occurred in a xenograft model, and this was dependent on TCR and IL-18R signaling. IL-18 augmented IFN-γ secretion and proliferation of T cells activated by the endogenous TCR. TCR-deficient, human IL-18-expressing CD19 CAR T cells exhibited enhanced proliferation and antitumor activity in the xenograft model. Antigen-propelled activation of cytokine helper ensemble (APACHE) CAR T cells displayed inducible expression of IL-18 and enhanced antitumor immunity. In an intact mouse tumor model, CD19-IL-18 CAR T cells induced deeper B cell aplasia, significantly enhanced CAR T cell proliferation, and effectively augmented antitumor effects in mice with B16F10 melanoma. These findings point to a strategy to develop universal CAR T cells for patients with solid tumors

Nitrogen Deposition Enhances the Positive Contribution of CO₂ Fertilization to China’s Carbon and Water Use Efficiencies

With climate change, Nitrogen deposition (ND) and carbon dioxide (CO2) have increased significantly, but the effects of ND and CO2 fertilization on carbon-use efficiency (CUE) and water-use efficiency (WUE) are still unclear. Therefore, the effects of ND and CO2 on CUE and WUE are studied by means of trend analysis and partial derivatives. The results show the following: (1) From 2000 to 2020, the mean CUE in China was 0.533, and the WUE was 1.235 g C kg−1 H2O. (2) In the study area, a 53.8% CUE and 61.8% WUE showed an upward trend, and ND enhanced the positive contribution of CO2 to CUE and WUE by 15.9% and 19.3%, respectively. (3) ND explained 48.1% and 56% of the increase in CUE and WUE, respectively, and CO2 explained 45.8% and 50.1% of the increases in CUE and WUE, respectively. (4) The areas dominated by ND and CO2 accounted for 43.9% and 12.7% of the total area, respectively, highlighting the importance of ND in the driving mechanism of CUE and WUE. The research results are helpful to further research in CUE and WUE