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Since China's reform and opening up in 1978, the reclamation and abandonment of cropland in Xinjiang have become significant features of the land use change in the arid land of Northwest China. However, the spatiotemporal changes and driving mechanisms of cropland reclamation and abandonment over long time periods are still unclear, but this is crucial in understanding cropland changes in inland arid land, providing important insights for land management and agricultural development. Based on 40 years of remote sensing data on resources and the environment, this study examines the spatiotemporal characteristics of cropland reclamation and abandonment in Xinjiang over four periods since 1980. Additionally, it uses an optimal parameter geographical detector model to quantify the driving factors for each period. The results indicate that cropland reclamation experiences a "slow decrease–rapid increase" trend, forming a "V-shaped" pattern, while abandonment shows a "rapid decrease–slow decrease–slow increase" trend, forming a "U-shaped" pattern. These trends can be divided into three periods: 1980–1990 (unstable growth), 1990–2010 (stable growth), and 2010–2020 (growth with constraints). The movement pattern of cropland reclamation's center of gravity is "slightly southeast–slightly northeast–southwest", whereas the abandonment's center of gravity shifts "northeast–southwest–northeast". Further analysis reveals that the impact of agricultural technological investment and infrastructure on cropland reclamation has increased, while the influence of natural environmental factors has decreased. Although climate and water resources remain key factors in cropland abandonment, the influence of economic and social factors has gradually diminished, and the impact of agricultural mechanization has steadily risen. [ABSTRACT FROM AUTHOR]

Objectives: This study delves into the association between dietary niacin intake and Helicobacter pylori seropositivity, a topic gaining prominence in academic discourse. However, the precise role of Niacin in the development and progression of Helicobacter pylori seropositivity remains inadequately understood. Thus, this research aims to investigate the connections between H. pylori seropositivity and dietary niacin intake using a nationally representative sample of adults. Methods: A cross-sectional analysis encompassed 4,000 participants from the National Health and Nutrition Examination Survey (NHANES) conducted in the United States between 1999 and 2000, all aged 20 years or older. The study employed the generalized additive model (GAM) and multivariate logistic regression to explore the potential relationship between niacin intake and Helicobacter pylori seropositivity. Subgroup analyses were performed based on gender, age, diabetes, hypertension, and hyperlipemia. Results: Analyzing cross-sectional data from NHANES 1999–2000 involving individuals aged 20 years and above revealed that out of 4,000 participants, 1,842 tested positive for H. pylori via serology. Multivariate analyses unveiled a significant inverse correlation between niacin intake and H. pylori seropositivity. Adjusted odds ratios (ORs) for dietary niacin intake in quartiles Q2 (13.31–19.26 mg/d), Q3 (19.27–27.42 mg/d), and Q4 (>27.42 mg/d) compared to Q1 (<13.31 mg/d) were 0.83 (95% CI: 0.69–1.01), 0.74 (95% CI: 0.61–0.90), and 0.66 (95% CI: 0.54–0.81), respectively. Moreover, a nonlinear L-shaped relationship (P = 0.022) emerged between niacin intake and H. pylori seropositivity, indicating minimal risk of H. pylori infection at approximately 44.69 mg of niacin per day in the diet. Conclusion: This study suggests a potential link between increased dietary niacin intake and reduced prevalence of Helicobacter pylori seropositivity. This correlation is bolstered by plausible mechanisms involving immunomodulatory function, mitochondrial dysfunction, and cellular oxidative stress. [ABSTRACT FROM AUTHOR]

Mounting evidence indicates a complex link between circulating saturated fatty acids (SFAs) and cardiovascular disease (CVD) risk factors, but research on erythrocyte membrane SFA associations with metabolic markers remains limited. Our study sought to investigate the correlations between erythrocyte membrane SFAs and key metabolic markers within glycemic and lipid metabolism in a Chinese population of 798 residents aged 41 to 71 from Guangzhou. Using gas chromatography–mass spectrometry, we assessed the erythrocyte membrane saturated fatty acid profile and performed multiple linear regression to evaluate the relationship between different SFA subtypes and metabolic markers. Our findings revealed that the odd-chain SFA group (C15:0 + C17:0) exhibited negative associations with fasting blood glucose (FBG), homeostatic model assessment for insulin resistance (HOMA-IR), and triglycerides (TG). Conversely, the very-long-chain SFA group (C20:0 + C22:0 + C23:0 + C24:0) exhibited positive associations with fasting insulins (FINS), HOMA-IR, total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C). Furthermore, there was no evidence supporting an association between the even-chain group (C14:0 + C16:0 + C18:0) and metabolic markers. Our findings suggest that different subtypes of SFAs have diverse effects on glycemic and lipid metabolic markers, with odd-chain SFAs associated with a lower metabolic risk. However, the results concerning the correlations between even-chain SFAs and very-long-chain SFAs with markers of glycemic and lipid metabolism pathways are confusing, highlighting the necessity for further exploration and investigation. [ABSTRACT FROM AUTHOR]

Soil organic carbon stock (SOCS) changes caused by land use changes are still unclear, and understanding this response is essential for many environmental policies and land management practices. In this study, we investigated the temporal–spatial and vertical distribution characteristics of the SOCS in the Western Sichuan Plateau (WSP) using the sparrow search algorithm–random forest regression (SSA-RFR) models with excellent model applicability and accuracy. The temporal–spatial variations in the SOCS were modeled using 1080 soil samples and a set of nine environmental covariates. We analyzed the effect of land use changes on the SOCS in the WSP. The total SOCS increased by 18.03 Tg C from 1990 to 2020. The results of this study confirmed a significant increase in the SOCS in the study area since 2010. There was a 27.88 Tg C increase in the SOCS in 2020 compared to the total SOCS in 2010. We found that the spatial distribution of the SOCS increased from southeast to northwest, and the vertical distribution of the SOCS in the study area decreased with increasing soil depth. Forests and grasslands are the main sources of SOCS the total SOCS in the forest and grassland accounted for 37.53 and 59.39% of the total soil organic carbon (SOC) pool in 2020, respectively. The expansion of the wetlands, forest, and grassland areas could increase the SOCS in the study area. A timely and accurate understanding of the dynamics of SOC is crucial for developing effective land management strategies to enhance carbon sequestration and mitigate land degradation. [ABSTRACT FROM AUTHOR]

Light-emitting diodes (LEDs) are commonly used in plant lighting and displays because they emit red, green, blue, and other colors of monochromatic light with a relatively limited spectrum. In this paper, mesoporous zirconium-based metal–organic frameworks (m-UiO-66) were synthesized via a template-free method, and red carbon dots (pCDs) were synthesized via a solvothermal method. The red carbon dots were finally inserted into the mesoporous metal–organic framework's pores while being heated and stirred, which led to the production of pCDs@m-UiO-66. The findings demonstrate that pCDs@m-UiO-66 has high stability at room temperature in addition to being able to produce solid-state luminescence following the co-assembly of red carbon dots with mesoporous metal–organic frameworks. Moreover, the position of its emission peak was red-shifted and its emission properties could meet the light requirements of plant growth. The cultivation trials showed that this far-red emitting phosphor can be used to prepare FR-LED plant lighting lamps when mixed with YAG:Ce3+, which is useful to increase the biomass of Italian lettuce and drench beet seedlings due to their optimized luminescent properties. [ABSTRACT FROM AUTHOR]

Exploring efficient, low cost and stable electrocatalysts working at large current densities is crucial for upgrading the current industrial electrochemical water splitting. Herein, a novel FeS2/Fe–Ni3S2 heterostructure was successfully prepared via a simple one-step in situ hydrothermal vulcanization using F− regulation engineering. The FeS2/Fe–Ni3S2 heterostructure array exhibits low overpotentials for both the OER (180 mV @ 10 mA cm−2 and 300 mV @ 1 A cm−2) and the HER (105 mV @ 10 mA cm−2 and 344 mV @ 1 A cm−2) with high stability operating at 1 A cm−2 for 1000 h. In addition, the water-splitting system only needs 1.5 V to reach 10 mA cm−2 and shows prolonged stability of more than 1200 h at 1 A cm−2. The DFT calculations show that the electrons redistribute at the interface and favor the chemisorption of hydrogen and oxygen-containing intermediates. This work highlights a novel, low cost and practical electrode for industrial electrochemical water splitting. [ABSTRACT FROM AUTHOR]

Oasis cities are deeply affected by human activities in arid and semi-arid regions. Vegetation is an important repository in the carbon cycle of oasis urban ecosystems. The continuous expansion of urban has a disproportionate impact on the carbon sequestration capacity of vegetation. Till now, studies have been conducted to quantify the impact of urbanization on vegetation carbon sequestration capacity, the mechanism of such impact remains unclear and lacks systematic investigations, especially in oasis urban. Understanding the impact mechanism greatly benefits the sustainable development of oasis urban and regional carbon neutrality. To fill this knowledge gap, we design a theoretical framework to analyze the impact of urbanization on vegetation carbon sequestration capacity by isolating the direct and indirect impacts in Urumqi, China. Some results based on Landsat images indicated that the Impervious Surface Areas (ISAs) expanded by 436.98 km2 during 2000 – 2019. The Net Primary Productivity (NPP) calculated using the Vegetation Photosynthesis Model (VPM) was directly caused by the loss of 51.45 Gg C (1 Gg = 109 g). Another important finding proved that the direct carbon loss caused by urbanization did not change the upward trend of the total carbon sequestration capacity of vegetation, but only slowed down this upward trend by 20.86%. Our results provide new insights into urban vegetation carbon sinks and contribute to a better understanding of the uncertainty of urbanization toward carbon neutrality. This study will provide scientific data support and suggestions for the sustainable development of oasis cities and the regional carbon budget. [ABSTRACT FROM AUTHOR]

Developing highly efficient, low cost, and stable electrocatalysts that work at a large current density is crucial for upgrading the current industrial electrochemical water splitting to produce H2. Molybdenum selenide (MoSe2) is a promising 2D transition metal dichalcogenide (TMD), however, its reported output is inadequate due to its inert basal plane. Herein, the catalytic activity of MoSe2 nanosheet arrays is activated by a novel and controllable method of He+ ion irradiation to introduce multiple vacancies simultaneously into their inert basal planes. The vacancies activated MoSe2 have improved electrocatalytic performance and stability with a minimum overpotential of 90 mV at 10 mA cm−2, a Tafel slope of 49 mV dec−1 and high stability of 650 h at the industry‐level large current density of 1000 mA cm−2 compared to several hours for the pristine sample. The DFT results reveal that single Se and single Mo vacancies on the MoSe2 basal plane can efficiently increase the electrical conductivity and reduce energy barriers for water dissociation and subsequent proton adsorption, thus improving the electrocatalytic capability. This finding proves the application of ion beam in defect engineering for effective hydrogen evolution in TMDs‐based catalysts. [ABSTRACT FROM AUTHOR]