Investigating drivers of N2 loss and N2O reducers in paddy soils across China.

Denitrification plays a pivotal role in nitrogen (N) cycling in rice paddies, significantly impacting N loss and greenhouse gas emissions. Accurate quantification of net N2 emissions from paddy fields is therefore essential for improving fertilizer N use efficiency. However, challenges in directly measuring gaseous N2 hinder our understanding of microbially-mediated N loss in paddy soils at large scales. In this study, we investigated net N2 loss and its influencing factors in 45 paddy soils across China using membrane inlet mass spectrometry and N2/Ar technique, complemented by microbial community analysis via metagenomics. Potential N2 loss rates varied from 0.41 to 3.58 nmol N g-1 h-1, with no significant regional differences. However, soils from rice-upland rotation (1.72 ± 0.64 nmol N g-1 h-1) and mono-rice cropping systems (1.41 ± 0.53 nmol N g-1 h-1) exhibited higher N2 loss rates compared to double-rice cropping soils (1.13 ± 0.62 nmol N g-1 h-1). Our results revealed a unimodal relationship between soil N2 loss rates and soil pH, with N2O reducers and soil properties primarily regulating regional variations in N2 loss. Significant ecological differentiation was observed within both nosZ Clade I and Clade II, with soil pH emerging as the key factor shaping their community composition. Specifically, in rice-upland rotations, soil moisture and pH significantly influenced nosZ Clade I, while in double-rice cropping systems, soil texture and pH were the main factors affecting nosZ Clade II, thereby driving N2 loss. These findings enhance our understanding of N2 loss dynamics in paddy soil ecosystems, underscoring the critical role of N2O reducers on microbial-derived N2 loss and highlighting the importance of developing strategies to mitigate N2O emissions by balancing N2 loss through the manipulation of N2O-reducing and N2O-producing microbes.

Microplastics from polyvinyl chloride agricultural plastic films do not change nitrogenous gas emission but enhance denitrification potential.

The effects of microplastics (MPs) from agricultural plastic films on soil nitrogen transformation, especially denitrification, are still obscure. Here, using a robotized flow-through system, we incubated vegetable upland soil cores for 66 days with MPs from PE mulching film (F-PE) and PVC greenhouse film (F-PVC) and directly quantified the emissions of nitrogenous gases from denitrification under oxic conditions, as well as the denitrification potential under anoxic conditions. The impact of MPs on soil nitrogen transformation was largely determined by the concentration of the additive phthalate esters (PAEs) containing in the MPs. The F-PE MPs with low level of PAEs (about 0.006 %) had no significant effect on soil mineral nitrogen content and nitrogenous gas emissions under oxic conditions. In contrast, the F-PVC MPs with high levels of PAEs (about 11 %) reduced soil nitrate content under oxic conditions, probably owing to promoted microbial assimilation of nitrogen, as the emissions of denitrification products (N2, NO, and N2O) was not affected. However, the F-PVC MPs significantly enhanced the denitrification potential of the soil due to the increased abundance of denitrifiers under anoxic conditions. These findings highlight the disturbance of MPs from agricultural films, particularly the additive PAEs on nitrogen transformation in soil ecosystems.

Spraying calcium chloride helps to enhance the resistance of kidney bean plants to western flower thrips.

BACKGROUND: The western flower thrips (WFT), Frankliniella occidentalis (Thysanoptera: Thripidae), is a significant pest in horticulture and ornamental agriculture. While exogenous calcium (Ca) has been shown to confer plant immune responses against thrips, the detailed mechanisms of this interaction remain to be elucidated for improved thrips management strategies. This study aimed to assess the impact of exogenous Ca on WFT feeding behavior and to explore its role in enhancing the defense mechanisms of kidney bean plants against WFT attacks. We compared WFT feeding preferences and efficiency on kidney bean plants treated with H2O or Ca, and examined whether exogenous Ca improves plant defense responses to thrips attack. RESULTS: WFT exhibited less preference for feeding on Ca-treated plants over H2O-treated ones. The total duration of WFT's long-ingestion probes was significantly reduced on Ca-treated plants, indicating impaired feeding efficiency. Furthermore, WFT infestation activated both jasmonic acid (JA) and salicylic acid (SA) signaling pathways in kidney bean plants, and exogenous Ca application led to elevated levels of endogenous Ca2+ and CaM, up-regulation of genes associated with JA and SA pathways (LOX, AOS, PAL, and ß-1,3-glucanase), and increased accumulation of JA, SA, flavonoids, and alkaloids. CONCLUSION: Our findings demonstrate that the application of exogenous Ca enhances endogenous Ca2+, JA, and SA signaling pathways in kidney bean plants. This enhancement results in an up-regulation of the biosynthesis of flavonoid and alkaloid, thereby equipping the plants with an enhanced defense against WFT infestation. © 2024 Society of Chemical Industry.

Non-Linear Association Between Climatic Parameters and Bell's Palsy Prevalence of Hospital Outpatients: An Ecological Proof in Kunshan, Suzhou, China.

Objective: This study aimed to explore the relationship between climatic parameters and the daily cases of Bell's palsy (BP) among hospital outpatients, providing ecological evidence for understanding BP etiology and prevention. Methods: Retrospective analysis was conducted on data from 2187 BP patients who attended Kunshan First People's Hospital Outpatient Clinic from January 1, 2020, to December 31, 2022. Meteorological data, including temperature, relative humidity, precipitation, wind speed, sunshine duration, and atmospheric pressure, were collected and combined with daily BP case records. Additionally, air quality index was used as a covariate. Results: The number of new BP cases among outpatients showed a negative correlation with average daily temperature. A nonlinear relationship between daily average temperature and BP cases was observed through the generalized additive model (GAM). A significant negative correlation was identified between daily average temperature and BP cases, with inflection points at temperatures above 4.2°C, suggesting a potential decrease in BP risk with temperature rise beyond this threshold. Conclusion: This study provides ecological evidence of a link between climatic factors and BP occurrence. Temperature demonstrated a significant nonlinear negative correlation with daily BP incidence, highlighting temperature and cold exposure as key targets for BP prevention in Kunshan.

Biochar mitigates the stimulatory effects of straw incorporation on N2O emission and N2O/(N2O + N2) ratio in upland soil.

Straw incorporation, a common agricultural strategy designed to enhance soil organic carbon (SOC), often leads to increased nitrous oxide (N2O) emission, potentially offsetting benefits of SOC sequestration. However, the mechanism and mitigation options for the enhanced N2O emission following straw incorporation remain unclear. Here, N2 and N2O emission rate, as well as N2O/(N2O + N2) ratio under four different fertilization treatments [i.e., non-fertilization (Control), conventional chemical fertilization (CF), conventional chemical fertilization plus straw incorporation (SWCF), and conventional chemical fertilization plus straw and biochar incorporation (SWBCF)] were investigated by a robotized sampling and analysis system. High-throughput sequencing was also employed to assess the variation of bacterial community across different treatments. The results showed CF, SWCF, and SWBCF fertilization treatments significantly increased N2O emission rate by 1.04, 2.01, and 1.29 folds, respectively, relative to Control treatment. Albeit no significant enhancements in N2 emission rate, the N2O/(N2O + N2) ratio significantly increased by 65.53%, 1.10 folds, and 69.49% in CF, SWCF, and SWBCF treatments, respectively. The partial least squares path modeling analysis further revealed that fertilization treatments slightly increased N2 emission rate by increasing DOC content and keystone OTUs abundance. While the enhanced N2O emission rate and N2O/(N2O + N2) ratio in the fertilization treatments was primarily determined by reducing DOC/NO3- ratio and specific bacteria module abundance dominated by Gaiellales, Solirubrobacterales, and Micrococcales. Furthermore, SWBCF treatment alleviated the increase in net global warming potential due to straw incorporation, as indicated by the higher SOC sequestration and lower N2O/(N2O + N2) ratio therein. Collectively, these findings suggest that simultaneous application of straw and biochar has the potential to mitigate the risk of increased N2O emission from straw incorporation. This study provides valuable insights for developing targeted strategies in C sequestration and greenhouse gas mitigation, tackling the challenge presented by global climate change.

Clinical applications of superb microvascular imaging and virtual touch imaging quantification in pediatric mesenteric lymphadenitis diagnosis: A promising pathway to enhanced precision.

BACKGROUND: Mesenteric lymphadenitis (ML) demonstrates a distinctive inclination for the pediatric and adolescent demographic and the diagnosis of ML in young children poses a substantial challenge. OBJECTIVE: This prospective study aimed to assess the diagnostic efficacy of Superb Microvascular Imaging (SMI) and Virtual Touch Tissue Imaging quantification (VTIQ) in distinguishing pediatric mesenteric lymphadentitis. METHODS: We examined 82 mesentric lymph node (MLN) in pediatric patients with mesenteric lymphadentitis and 50 MLN in a healthy group. SMI was utilized to evaluate vascularity within the MLN, while MLN stiffness, quantified as shear wave velocity (SWV) in meters per second (m/s), was assessed using VTIQ. We compared the diagnostic performance of greyscale Ultrasound, US combined with SMI, US combined with VTIQ, and US combined with both SMI and VTIQ. RESULTS: SMI revealed a significant distinction between mesenteric lymphadentitis and normal MLN (p <  0.001). MLN affected by mesenteric lymphadentis exhibited increased vascularity (marked vascularity: 13/82, 15.85%) compared to normal MLN (marked vascularity: 1/50, 2.00%). Statistically significant differences were observed in SWV values beween mesenteric lymphadentitis and normal MLN (all p-values <0.001). The mean and minimum SWV values for MLN with mesenteric lymphadentitis were 1.66±0.77 m/s and 1.51±0.53 m/s, respectively. Control group SWV values were approximately three times higher than those in the mesenteric lymphadenitis group. The highest area under the curve values were achieved with the combination of all three modalities (0.837, 95% confidence interval: 0.763- 0.896), followed by US + VTIQ (0.795, 0.716- 0.860), US + SMI (0.753, 0.670- 0.824) and US alone (0.642, 0.554- 0.724). CONCLUSION: SMI and VTIQ offer a promising noninvasive adjunct to grayscale ultrasound for identifying mesenteric lymphadentitis in pediatric patients.

Changes in source composition of wet nitrate deposition after air pollution control in a typical area of Southeast China.

In recent years, China has adopted numerous policies and regulations to control NOx emissions to further alleviate the adverse impacts of NO3--N deposition. However, the variation in wet NO3--N deposition under such policies is not clear. In this study, the southeastern area, with highly developed industries and traditional agriculture, was selected to explore the variation in NO3--N deposition and its sources changes after such air pollution control through field observation and isotope tracing. Results showed that the annual mean concentrations of NO3--N in precipitation were 0.67 mg L-1 and 0.54 mg L-1 in 2014-2015 and 2021-2022, respectively. The average wet NO3--N depositions in 2014-2015 and 2021-2022 was 7.76 kg N ha-1 yr-1 and 5.03 kg N ha-1 yr-1, respectively, indicating a 35% decrease. The δ15N-NO3- and δ18O-NO3- values were lower in warm seasons and higher in cold seasons, and both showed a lower trend in 2021-2022 compared with 2014-2015. The Bayesian model results showed that the NOx emitted from coal-powered plants contributed 53.6% to wet NO3--N deposition, followed by vehicle exhaust (22.9%), other sources (17.1%), and soil emissions (6.4%) during 2014-2015. However, the contribution of vehicle exhaust (33.3%) overpassed the coal combustion (32.3%) and followed by other sources (25.4%) and soil emissions (9.0%) in 2021-2022. Apart from the control of air pollution, meteorological factors such as temperature, precipitation, and solar radiation are closely related to the changes in atmospheric N transformation and deposition. The results suggest phased achievements in air pollution control and that more attention should be paid to the control of motor vehicle exhaust pollution in the future, at the same time maintaining current actions and supervision of coal-powered plants.

A QTL GN1.1, encoding FT-L1, regulates grain number and yield by modulating polar auxin transport in rice.

Rice grain number is a crucial agronomic trait impacting yield. In this study, we characterized a quantitative trait locus (QTL), GRAIN NUMBER 1.1 (GN1.1), which encodes a Flowering Locus T-like1 (FT-L1) protein and acts as a negative regulator of grain number in rice. The elite allele GN1.1B, derived from the Oryza indica variety, BF3-104, exhibits a 14.6% increase in grain yield compared with the O. japonica variety, Nipponbare, based on plot yield tests. We demonstrated that GN1.1 interacted with and enhanced the stability of ADP-ribosylation factor (Arf)-GTPase-activating protein (Gap), OsZAC. Loss of function of OsZAC results in increased grain number. Based on our data, we propose that GN1.1B facilitates the elevation of auxin content in young rice panicles by affecting polar auxin transport (PAT) through interaction with OsZAC. Our study unveils the pivotal role of the GN1.1 locus in rice panicle development and presents a novel, promising allele for enhancing rice grain yield through genetic improvement.

Johnson-noise-limited cancellation-free microwave impedance microscopy with monolithic silicon cantilever probes.

Microwave impedance microscopy (MIM) is an emerging scanning probe technique for nanoscale complex permittivity mapping and has made significant impacts in diverse fields. To date, the most significant hurdles that limit its widespread use are the requirements of specialized microwave probes and high-precision cancellation circuits. Here, we show that forgoing both elements not only is feasible but also enhances performance. Using monolithic silicon cantilever probes and a cancellation-free architecture, we demonstrate Johnson-noise-limited, drift-free MIM operation with 15 nm spatial resolution, minimal topography crosstalk, and an unprecedented sensitivity of 0.26 zF/√Hz. We accomplish this by taking advantage of the high mechanical resonant frequency and spatial resolution of silicon probes, the inherent common-mode phase noise rejection of self-referenced homodyne detection, and the exceptional stability of the streamlined architecture. Our approach makes MIM drastically more accessible and paves the way for advanced operation modes as well as integration with complementary techniques.

Value of conventional ultrasound and shear­wave elastography in the assessment of mesenteric lymphadenitis in a paediatric population.

The present retrospective study was designed to explore the value of conventional ultrasound (US) and Virtual Touch Tissue Imaging and Quantification (VTIQ) in the assessment of mesenteric lymphadenitis (ML) in a paediatric population. A total of 103 patients with ML and 60 healthy paediatric patients were examined. VTIQ was performed to assess mesenteric lymph node (MLN) stiffness via shear-wave velocity (SWV). Univariate and multivariate logistic regression analyses were conducted to reveal independent variables for the identification of ML. The diagnostic performance of US, and US combined with VTIQ, were compared. All the quantitative VTIQ parameters (including the SWVMean, SWVMax and SWVMin) were significantly greater for MLNs in the control group than for MLNs in the ML group (all P<0.001). The SWV values in the control group were nearly 2-fold greater than that in the ML group. According to the multivariate logistic regression analysis, the longest diameter [odds ratio (OR)=6.042; P=0.046] was revealed to be the strongest independent predictor for ML, followed by the CRP level (OR=2.310; P<0.001) and the SWVMean (OR=0.106; P<0.001). According to the receiver operating characteristic analysis, the area under the curve (AUC) for US combined with VTIQ was 0.890 (95% CI: 0.831-0.949) with a greater sensitivity of 91.26% and a greater specificity of 86.67% than that for US alone (AUC: 0.798; 95% CI: 0.724-0.872; sensitivity: 79.61%; specificity: 80.00%). A significant negative correlation between increased VTIQ parameters and ML was observed. Utilizing VTIQ to assess MLN stiffness offers a non-invasive, convenient, reliable and reproducible approach for identifying mesenteric lymphadenopathy.

Exploring dissolved N2O characteristics and unearthing indirect N2O emission factors in the shallow groundwater of paddy and upland fields.

Indirect emissions of nitrous oxide (N2O) stemming from nitrogen (N) leaching in agricultural fields constitute a significant contributor to atmospheric N2O. Groundwater nitrate (NO3--N) pollution is severe in the Ningxia Yellow River Irrigation Area (NYRIA), coupled with high NO3--N leaching, exacerbates the risk of indirect N2O emissions from groundwater. Over two years of field observations, this study investigated the characteristics and interannual variations of dissolved N2O (dN2O) concentrations and indirect N2O emission factors (EF5g) in shallow groundwater. The research focused on three typical farmlands in the NYRIA, each subjected to six levels of N fertilizer application. The mean dN2O concentrations in the groundwater of paddy, corn and vegetable fields were 5.17, 8.40 and 16.35 µg N·L-1, respectively. Notably, the dN2O concentrations in the shallow groundwater of upland fields exceeded those in paddy fields, with maximum levels in vegetable fields nearly an order of magnitude higher. Elevated N application significantly increased dN2O concentrations across various farmlands, showing statistically significant variation. However, differences in EF5g-A and EF5g-B within the same farmland were negligible. Denitrification was the primary process contributing to N2O production in groundwater, with nitrification also played a crucial role in upland fields. Factors such as NO3--N, NH4+-N, dissolved oxygen (DO), and pH critically influenced N2O production. EF5g-B, which considers the NO3--N consumption during denitrification processes in groundwater, was deemed more appropriate than EF5g-A for assessing the indirect N2O emission in the NYRIA. The EF5g of agricultural fields exhibited minimal sensitivity to N input but was significantly affected by other factors, such as the planting pattern. The study revealed the rationality of adopting EF5g-B in assessing indirect N2O emissions, providing valuable insights for N management strategies in regions with high NO3--N leaching. Minimizing N fertilizer application while ensuring crop yield, especially in upland fields, is beneficial for reducing N2O emissions.

Body mass index and multimorbidity risk: A systematic review and dose-response meta-analysis.

OBJECTIVE: To verify the dose-response relationship between body mass index (BMI) and multimorbidity risk. METHODS: PubMed, CINAHL, and Embase were systematically studied until January 25, 2023. Original articles on BMI and multimorbidity risk were included. Random effects model and dose-response meta-analysis were used to estimate the pooled odds ratio (OR) with 95 % confidence interval (CI). Subgroup analysis was performed to explore potential heterogeneity. RESULTS: A total of 43 studies involving 969,130 patients (94,978 with multimorbidity) were involved in the meta-analysis. In the longitudinal studies, the pooled results showed that, compared to being a normal BMI, being overweight was much similar with 1.32 times possibility of getting multimorbidity; in persons with obesity the risk was 1.93 times higher; and the risk decreased 0.80 times among underweight persons. Additionally, obesity was 1.75 times as likely to be multimorbidity than those non-obese persons. In the cross-sectional studies, the pooled results demonstrated that persons with overweight and obesity had a 1.38-fold and 2.38-fold risk for multimorbidity, respectively; and the risk decreased 0.90 times among underweight persons compared to those with normal BMI. Besides, obese people are 1.89 times more likely to have multimorbidity than non-obese people. Dose response analysis found the linear connection between BMI and multimorbidity risk (Pnon-linearity=0.762), that for each 1 kg/m2 and 5 kg/m2 increase in BMI, the multimorbidity risk increased by 6 % and 35 %, respectively. CONCLUSIONS: Multimorbidity increased linearly with an increase in BMI. Clinicians should pay attention to persons with abnormal weight, to help them achieve normal BMI.

Electrostatic Gating of Spin Dynamics of a Quasi-2D Kagome Magnet.

Electrostatic gating has emerged as a powerful technique for tailoring the magnetic properties of two-dimensional (2D) magnets, offering exciting prospects including enhancement of magnetic anisotropy, boosting Curie temperature, and strengthening exchange coupling effects. Here, we focus on electrical control of the ferromagnetic resonance of the quasi-2D Kagome magnet Cu(1,3-bdc). By harnessing an electrostatic field through ionic liquid gating, significant shifts are observed in the ferromagnetic resonance field in both out-of-plane and in-plane measurements. Moreover, the effective magnetization and gyromagnetic ratios display voltage-dependent variations. A closer examination reveals that the voltage-induced changes can modulate magnetocrystalline anisotropy by several hundred gauss, while the impact on orbital magnetization remains relatively subtle. Density functional theory (DFT) calculations reveal varying d-orbital hybridizations at different voltages. This research unveils intricate physics within the Kagome lattice magnet and further underscores the potential of electrostatic manipulation in steering magnetism with promising implications for the development of spintronic devices.

Dysfunction of duplicated pair rice histone acetyltransferases causes segregation distortion and an interspecific reproductive barrier.

Postzygotic reproductive isolation, which results in the irreversible divergence of species, is commonly accompanied by hybrid sterility, necrosis/weakness, or lethality in the F1 or other offspring generations. Here we show that the loss of function of HWS1 and HWS2, a couple of duplicated paralogs, together confer complete interspecific incompatibility between Asian and African rice. Both of these non-Mendelian determinants encode the putative Esa1-associated factor 6 (EAF6) protein, which functions as a characteristic subunit of the histone H4 acetyltransferase complex regulating transcriptional activation via genome-wide histone modification. The proliferating tapetum and inappropriate polar nuclei arrangement cause defective pollen and seeds in F2 hybrid offspring due to the recombinant HWS1/2-mediated misregulation of vitamin (biotin and thiamine) metabolism and lipid synthesis. Evolutionary analysis of HWS1/2 suggests that this gene pair has undergone incomplete lineage sorting (ILS) and multiple gene duplication events during speciation. Our findings have not only uncovered a pair of speciation genes that control hybrid breakdown but also illustrate a passive mechanism that could be scaled up and used in the guidance and optimization of hybrid breeding applications for distant hybridization.

Fate of sulfamethoxazole in wetland sediment under controlled redox conditions.

Redox condition is an important controlling factor for contaminant removal in constructed wetlands; however, the redox-sensitivity of antibiotic removal in wetland sediments under controlled conditions with specific electron acceptors remains unclear. Here, using a 14C radioactive tracer, we explored fate of sulfamethoxazole (SMX) in a wetland sediment slurry under oxic, nitrate-reducing, iron-reducing, and methanogenic conditions. In the sterile treatment, unlike the comparable SMX dissipation from the water phase under four redox conditions, non-extractable residues (NERs) of SMX was highest formed in the sediment under oxic condition, mainly in sequestered and ester/amide-linked forms. Microorganisms markedly promoted SMX transformation in the slurry. The dissipation rate of SMX and its transformation products (TPs) followed the order: oxic ≈ iron-reducing > methanogenic >> nitrate-reducing conditions, being consistent with the dynamics of microbial community in the sediment, where microbial diversity was greater and networks connectivity linking dominant bacteria to SMX transformation were more complex under oxic and iron-reducing conditions. Kinetic modeling indicated that the transformation trend of SMX and its TPs into the endpoint pool NERs depended on the redox conditions. Addition of wetland plant exudates and sediment dissolved organic matter at environmental concentrations affected neither the abiotic nor the biotic transformation of SMX. Overall, the iron-reducing condition was proven the most favorable and eco-friendly for SMX transformation, as it resulted in a high rate of SMX dissipation from water without an increase in toxicity and subsequent formation of significant stable NERs in sediment. Our study comprehensively revealed the abiotic and biotic transformation processes of SMX under controlled redox conditions and demonstrated iron-reducing condition allowing optimal removal of SMX in constructed wetlands.

Coping with groundwater pollution in high-nitrate leaching areas: The efficacy of denitrification.

The Ningxia Yellow River irrigation area, characterized by an arid climate and high leaching of NO3--N, exhibits complex and unique groundwater nitrate (NO3--N) pollution, with denitrification serving as the principal mechanism for NO3--N removal. The characteristics of N leaching from paddy fields and NO3--N removal by groundwater denitrification were investigated through a two-year field observation. The leaching losses of total nitrogen (TN) and NO3--N accounted for 10.81-27.34% and 7.59-12.74%, respectively, of the N input. The linear relationship between NO3--N leaching and N input indicated that the fertilizer-induced emission factor (EF) of NO3--N leaching in direct dry seeding and seedling-raising and transplanting paddy fields was 8.2% (2021, R2 = 0.992) and 6.7% (2022, R2 = 0.994), respectively. The study highlighted that the quadratic relationship between the NO3--N leaching loss and N input (R2 = 0.999) significantly outperformed the linear relationship. Groundwater denitrification capacity was characterized by monitoring the concentrations of dinitrogen (N2) and nitrous oxide (N2O). The results revealed substantial seasonal fluctuations in excess N2 and N2O concentrations in groundwater, particularly following fertilization and irrigation events. The removal efficiency of NO3--N via groundwater denitrification ranged from 42.70% to 74.38%, varying with depth. Groundwater denitrification capacity appeared to be linked to dissolved organic carbon (DOC) concentration, redox conditions, fertilization, irrigation, and soil texture. The anthropogenic-alluvial soil with limited water retention accelerated the leaching of NO3--N into groundwater during irrigation. This process enhances the groundwater recharge capacity and alters the redox conditions of groundwater, consequently impacting groundwater denitrification activity. The DOC concentration emerged as the primary constraint on the groundwater denitrification capacity in this region. Hence, increasing carbon source concentration and enhancing soil water retention capacity are vital for improving the groundwater denitrification capacity and NO3--N removal efficiency. This study provides practical insights for managing groundwater NO3--N pollution in agricultural areas, optimizing fertilization strategies and improving groundwater quality.

Fatigue and sleep quality in Chinese adults with connective tissue disease: A cross-sectional study.

OBJECTIVES: This study aims to evaluate fatigue and sleep quality among adults with connective tissue disease (CTD), and the interrelationship. METHODS: From April 2020 to February 2021, adult CTD patients hospitalized were invited to complete sociodemographic and disease-related data, Fatigue Severity Scale (FSS), and Pittsburgh Sleep Quality Index (PSQI), as well as laboratory detection through computer query. Statistical analysis was performed using SPSS 22.0. RESULTS: A total of 363 patients with CTD were included in the study. Of which, 313 patients were accompanied by single CTD (systemic lupus erythematosus (SLE) = 109, Sjogren's syndrome (SS) = 51, rheumatoid arthritis (RA) = 44, idiopathic inflammatory myopathies (IIM) = 36, Vasculitis = 17, systemic sclerosis (SSc) = 14, other = 42, respectively), and 50 patients had CTD ≥ 2. Compared with CTD = 1, patients with CTD ≥ 2 had longer disease duration, higher erythrocyte sedimentation rate, and higher IgG level (all P < 0.05). The prevalence of poor sleep quality in 363 CTD patients was 61.2%, among which, 59.1% for CTD = 1 and 74.0% for CTD ≥ 2, with significant difference (P = 0.045). Additionally, 75.5% experienced fatigue, and 75.4% for CTD = 1, 76.0% for CTD ≥ 2 (P = 0.927). Fatigue and sleep quality interacted in CTD patients (r = 0.236, P < 0.01; χ2 = 11.302, P = 0.001). Interestingly, no significant differences were found in the prevalence of fatigue and poor sleep quality among CTD subgroups, as well as the FSS score, the seven components of sleep quality and total PSQI score (P > 0.05). CONCLUSIONS: More than 3/5 CTD patients experience fatigue and poor sleep quality, and not different among CTD subgroups. Targeted interventions are needed to reduce fatigue, improve sleep quality, and ultimately improve the prognosis of patients with CTD.

Drainage ditches are significant sources of indirect N2O emissions regulated by available carbon to nitrogen substrates in salt-affected farmlands.

Agriculture is a main source of nitrous oxide (N2O) emissions. In agricultural systems, direct N2O emissions from nitrogen (N) addition to soils have been widely investigated, whereas indirect emissions from aquatic ecosystems such as ditches are poorly known, with insufficient data available to refine the IPCC emission factor. In this contribution, in situ N2O emissions from two ditch water‒air interfaces based on a diffusion model were investigated (almost once per month) from June 2021 to December 2022 in an intensive arable catchment with high N inputs and salt-affected conditions in the Qingtongxia Irrigation District, northwestern China. Our results implied that agricultural ditches (mean 148 µg N m-2 h-1) were significant sources for N2O emissions, and were approximately 2.1 times greater than those of the Yellow River directly connected to ditches. Agronomic management strategies increased N2O fluxes in summer, while precipitation events decreased N2O fluxes. Agronomic management strategies, including fertilization (294--540 kg N hm-2) and irrigation on farmland, resulted in enhanced diffuse N loads in drain water, whereas precipitation diluted the dissolved N2O concentration in ditches and accelerated the ditch flow rate, leading to changes in the residence time of N-containing substances in water. The spatial analysis showed that N2O fluxes (202-233 µg N m-2 h-1) in the headstream and upstream regions of ditches due to livestock and aquaculture pollution sources were relatively high compared to those in the midstream and downstream regions (100-114 µg N m-2 h-1). Furthermore, high available carbon (C) relative to N reduced N2O fluxes at low DOC:DIN ratio levels by inhibiting nitrification. Spatiotemporal variations in the N2O emission factor (EF5) across ditches with higher N resulted in lower EF5 and a large coefficient of variation (CV) range. EF5 was 0.0011 for the ditches in this region, while the EF5 (0.0025) currently adopted by the IPCC is relatively high. The EF5 variation was strongly controlled by the DOC:DIN ratio, TN, and NO3--N, while salinity was also a nonnegligible factor regulating the EF5 variation. The regression model incorporating NO3--N and the DOC:DIN ratio could greatly enhance the predictions of EF5 for agricultural ditches. Our study filled a key knowledge gap regarding EF5 from agricultural ditches in salt-affected farmland and offered a field investigation for refining the EF5 currently used by the IPCC.

Ditch level-dependent N removal capacity of denitrification and anammox in the drainage system of the Ningxia Yellow River irrigation district.

Drainage networks, consisting of different levels of ditches, play a positive role in removing reactive nitrogen (N) via self-purification before drainage water returns to natural water bodies. However, relatively little is known about the N removal capacity of irrigation agricultural systems with different drainage ditch levels. In this study, we employed soil core incubation and soil slurry 15N paired tracer techniques to investigate the N removal rate (i.e., N2 flux), denitrification, anaerobic ammonium oxidation (anammox), and dissimilatory nitrate reduction to ammonium (DNRA) rates in the Ningxia Yellow River irrigation district at various ditch levels, including field ditches (FD), paddy field ditches (PFD), lateral ditches (LD1 and LD2), branch ditches (BD1, BD2, BD3), and trunk ditches (TD). The results indicated that the N removal rate ranged from 44.7 to 165.22 nmol N g-1 h-1 in the ditches, in the following decreasing order: trunk ditches > branch ditches > paddy field ditches > lateral ditches > field ditches. This result suggested that the N removal rate in drainage ditches is determined by the ditch level. In addition, denitrification and anammox were the primary pathways for N removal in the ditches, contributing 68.40-76.64 % and 21.55-30.29 %, respectively, to the total N removal. In contrast, DNRA contributed only 0.82-2.15 % to the total nitrate reduction. The N removal rates were negatively correlated with soil EC and pH and were also constrained by the abundances of denitrification functional genes. Overall, our findings suggest that the ditch level should be considered when evaluating the N removal capacity of agricultural ditch systems.

Thirty years of experience in water pollution control in Taihu Lake: A review.

Taihu Lake has suffered from eutrophication and algal blooms for decades, primarily due to increasing anthropogenic pollutants from human activities. Extensive research and widespread implementation of water pollution control measures have significantly contributed to the improvement of water quality of Taihu Lake. However, the relevant experience of Taihu Lake pollution control has not been well summarized to provide insight for future lake restoration. This review article seeks to address this gap by first providing a comprehensive overview of Taihu Lake's water quality dynamics over the past thirty years, characterized by two distinct stages: (I) water quality deterioration (1990s-2007); and (II) water total nitrogen (TN) improvement but total phosphorus (TP) fluctuation (2007-current). Subsequently, we conducted a thorough review of the experiences and challenges associated with water pollution control during these two stages. Generally, pollution control practices emphasized point source control but overlooked non-point sources before 2007, possibly due to point sources being easier to identify and manage. Accordingly, the focus shifted from industrial point sources to a combination of industrial point and agricultural non-point sources after 2007 to control water pollution in the Taihu Lake Basin. Numerous studies have delved into non-point source pollution control, including source control, transport intercept, in-lake measures, and the integration of these technologies. Taken together, this paper provides suggestions based on the needs and opportunities of this region. Further research is needed to better understand and model the underlying pollution processes, as well as to increase public participation and improve policy and law implementation, which will assist decision-makers in formulating better water management in Taihu Lake.