Mitochondrial endogenous substance transport-inspired nanomaterials for mitochondria-targeted gene delivery.

Mitochondrial genome (mtDNA) independent of nuclear gene is a set of double-stranded circular DNA that encodes 13 proteins, 2 ribosomal RNAs and 22 mitochondrial transfer RNAs, all of which play vital roles in functions as well as behaviors of mitochondria. Mutations in mtDNA result in various mitochondrial disorders without available cures. However, the manipulation of mtDNA via the mitochondria-targeted gene delivery faces formidable barriers, particularly owing to the mitochondrial double membrane. Given the fact that there are various transport channels on the mitochondrial membrane used to transfer a variety of endogenous substances to maintain the normal functions of mitochondria, mitochondrial endogenous substance transport-inspired nanomaterials have been proposed for mitochondria-targeted gene delivery. In this review, we summary mitochondria-targeted gene delivery systems based on different mitochondrial endogenous substance transport pathways. These are categorized into mitochondrial steroid hormones import pathways-inspired nanomaterials, protein import pathways-inspired nanomaterials and other mitochondria-targeted gene delivery nanomaterials. We also review the applications and challenges involving in current mitochondrial gene editing systems. This review delves into the approaches of mitochondria-targeted gene delivery, providing detail on the design of mitochondria-targeted delivery systems and limitations regarding the varying technologies. Despite the progress in this field is currently slow, the ongoing exploration of mitochondrial endogenous substance transport and mitochondrial biological phenomena may act as a crucial breakthrough in the targeted delivery of gene into mitochondria and even the manipulation of mtDNA.

Iodine(III)-Mediated Trifluoroacetylation of a C(sp2)-H or C(sp)-H Bond with Masked Trifluoroacyl Reagents.

A novel strategy for incorporating a trifluoroacetyl functionality into a range of structurally varied unsaturated bonds was developed by using PhI(OCOMe)2 as an oxidant with a masked trifluoroacyl reagent as a trifluoroacetyl radical precursor. The oxidative decarboxylation of the masked trifluoroacyl precursor followed by a tandem radical process provides versatile access to 5-exo-trig cyclization of N-arylacrylamides, direct C(sp2)-H trifluoroacetylation of quinolines, isoquinoline, 2H-indazole, and quinoxalin-2(1H)-ones, and C(sp)-H trifluoroacetylation of alkynes. This protocol is characterized by mild reaction conditions, operational simplicity, and broad functional group compatibility.

Examining the Use and Application of the WHO Integrated People-Centred Health Services Framework in Research Globally - a Systematic Scoping Review.

Introduction: The World Health Organisation (WHO) accepted the Integrated People-centred Health Services (IPCHS) framework in 2016 as an essential component for achieving universal health coverage in fragmented health systems. We aimed to examine the empirical applications of the WHO IPCHS framework to guide its use in strengthening health-service research. Methods: Academic databases and the IPCHS website were searched for relevant articles published between 2016 and July 2023. Two reviewers independently screened and extracted data on the study design, setting, IPCHS framework components, and facilitators and barriers to implementing the IPCHS strategies. Descriptive and content analyses were conducted. Results: Six studies were identified using the IPCHS framework. Studies have examined a combination of the five IPCHS strategies. All studies reported building strong primary care-based systems and coordinating care for individuals. Continued relationships and trust, co-production of health programmes, diversity of health care team, and technology were major facilitators, while low health literacy, lack of primary setting capacity and healthcare workforce were principal barriers to IPCHS implementation. Conclusion: This scoping review offers an overview of IPCHS strategies employed in healthcare research. Generally, the IPCHS framework remains underutilised in primary research. These results offer guidance for future research to support effective healthcare delivery.

Biochar and hydrochar application influence soil ammonia volatilization and the dissolved organic matter in salt-affected soils.

Biochar, which including pyrochar (PBC) and hydrochar (HBC), has been tested as a soil enhancer to improve saline soils. However, the effects of PBC and HBC application on ammonia (NH3) volatilization and dissolved organic matter (DOM) in saline paddy soils are poorly understood. In this research, marsh moss-derived PBC and HBC biochar types were applied to paddy saline soils at 0.5 % (w/w) and 1.5 % (w/w) rates to assess their impact on soil NH3 volatilization and DOM using a soil column experiment. The results revealed that soil NH3 volatilization significantly increased by 56.1 % in the treatment with 1.5 % (w/w) HBC compared to the control without PBC or HBC. Conversely, PBC and the lower application rate of HBC led to decrease in NH3 volatilization ranging from 2.4 % to 12.1 %. Floodwater EC is a dominant factor in NH3 emission. Furthermore, the fluorescence intensities of the four fractions (all humic substances) were found to be significantly higher in the 1.5 % (w/w) HBC treatment applied compared to the other treatments, as indicated by parallel factor analysis modeling. This study highlights the potential for soil NH3 losses and DOM leaching in saline paddy soils due to the high application rate of HBC. These findings offer valuable insights into the effects of PBC and HBC on rice paddy saline soil ecosystems.

Understanding Gaps in the Hypertension and Diabetes Care Cascade: Systematic Scoping Review.

BACKGROUND: Hypertension and diabetes are global health challenges requiring effective management to mitigate their considerable burden. The successful management of hypertension and diabetes requires the completion of a sequence of stages, which are collectively termed the care cascade. OBJECTIVE: This scoping review aimed to describe the characteristics of studies on the hypertension and diabetes care cascade and identify potential interventions as well as factors that impact each stage of the care cascade. METHODS: The method of this scoping review has been guided by the framework by Arksey and O'Malley. We systematically searched MEDLINE, Embase, and Web of Science using terms pertinent to hypertension, diabetes, and specific stages of the care cascade. Articles published after 2011 were considered, and we included all studies that described the completion of at least one stage of the care cascade of hypertension and diabetes. Study selection was independently performed by 2 paired authors. Descriptive statistics were used to elucidate key patterns and trends. Inductive content analysis was performed to generate themes regarding the barriers and facilitators for improving the care cascade in hypertension and diabetes management. RESULTS: A total of 128 studies were included, with 42.2% (54/128) conducted in high-income countries. Of them, 47 (36.7%) focused on hypertension care, 63 (49.2%) focused on diabetes care, and only 18 (14.1%) reported on the care of both diseases. The majority (96/128, 75.0%) were observational in design. Cascade stages documented in the literature were awareness, screening, diagnosis, linkage to care, treatment, adherence to medication, and control. Most studies focused on the stages of treatment and control, while a relative paucity of studies examined the stages before treatment initiation (76/128, 59.4% vs 52/128, 40.6%). There was a wide spectrum of interventions aimed at enhancing the hypertension and diabetes care cascade. The analysis unveiled a multitude of individual-level and system-level factors influencing the successful completion of cascade sequences in both high-income and low- and middle-income settings. CONCLUSIONS: This review offers a comprehensive understanding of hypertension and diabetes management, emphasizing the pivotal factors that impact each stage of care. Future research should focus on upstream cascade stages and context-specific interventions to optimize patient retention and care outcomes.

Visible-Light-Induced, Catalyst-Free Monofluoromethyl Sulfonylation of Alkenes with Iodine(III) Reagent and DABSO.

A visible-light-induced radical relay strategy to access heterocycles bearing a monofluoromethylsufonyl moiety is reported, with PhI(OCOCH2F)2 as the CH2F radical precursor and DABSO as the SO2 source. A range of oxindoles, containing a CH2FSO2CH2- group at the C3 position, were synthesized from N-arylacrylamides in up to 97% yields. The protocol features catalyst-free photochemical tandem, mild reaction conditions, broad functional group compatibility, and good to excellent yields.

Salinity-dependent potential soil fungal decomposers under straw amendment.

Soil salinization is a severe environmental problem that restricts plant productivity and ecosystem functioning. Straw amendment could increase the fertility of saline soils by improving microbial activity and carbon sequestration, however, the adaptation and ecological preference of potential fungal decomposers after straw addition under varied soil salinities remains elusive. Here, a soil microcosm study was conducted by incorporating wheat and maize straws into soils with a range of salinities, respectively. We showed that the amendment of straws increased MBC, SOC, DOC and NH4+-N contents by 75.0 %, 17.2 %, 88.3 % and 230.9 %, respectively, but decreased NO3--N content by 79.0 %, irrespective of soil salinity, with intensified connections among these parameters after straw addition. Although soil salinity had a more profound effect on both fungal α- and ß-diversity, straw amendment also significantly reduced fungal Shannon diversity and changed community composition, especially for severe saline soil. Complexity of the fungal co-occurrence network was specifically strengthened after straw addition, with average degree increasing from 11.9 in the control to 22.0 and 22.7 in wheat and maize straw treatments, respectively. Intriguingly, there was very little overlap among the straw-enriched ASVs (Amplicon Sequence Variants) in each saline soil, indicating the soil-specific involvement of potential fungal decomposers. Particularly, fungal species belonging to Cephalotrichum and unclassified Sordariales were the most responsive to straw addition in severe saline soil, whereas light saline soil supported the enrichment of Coprinus and Schizothecium species after straw addition. Together, our study provides a new insight on the common and specific responses of soil chemical and biological characteristics at different salinity levels under straw management, which will help guide precise microbial-based strategies to boost straw decomposition in future agricultural practice and environmental management of saline-alkali lands.

Coordinative Management of Soil Resources and Agricultural Farmland Environment for Food Security and Sustainable Development in China.

Major problems in China's pursuit of sustainable agricultural development include inadequate, low-quality soil and water resources, imbalanced regional allocation and unreasonable utilization of resources. In some regions, overexploitation of soil resources and excessive use of chemicals triggered a web of unforeseen consequences, including insufficient use of agricultural resources, agricultural non-point source pollution and land degradation. In the past decade, China has changed its path of agricultural development from an output-oriented one to a modern, sustainable one with agricultural ecological civilization as its goal. First, the government has formulated and improved its laws and regulations on soil resources and the environment. Second, the government has conducted serious actions to ensure food safety and coordinated management of agricultural resources. Third, the government has planned to establish national agricultural high-tech industry demonstration zones based on regional features to strengthen the connection among the government, agri-businesses, scientific community and the farming community. As the next step, the government should improve the system for ecological and environmental regulation and set up a feasible eco-incentive mechanism. At the same time, the scientific community should strengthen the innovation of bottleneck technologies and the development of whole solutions for sustainable management in ecologically fragile regions. This will enhance the alignment between policy mechanisms and technology modes and effectively promote the sustainable development of agriculture in China.

Effect of Adjuvant Radiation Dose on Survival in Patients with Esophageal Squamous Cell Carcinoma.

Background: For patients with esophageal squamous cell carcinoma (ESCC) treated with surgery alone, the incidence of local-regional recurrence remains unfavorable. Postoperative radiotherapy (PORT) has been associated with increased local-regional recurrence-free survival (LRFS), although its application is limited by concerns of PORT-related toxicities. Methods: Among 3591 patients with ESCC analyzed in this study, 2765 patients with T3-4N0 and T1-4N1-3 lesions and specific local-regional status information were analyzed in a subsequent analysis of adjuvant radiation dose (aRTD) effect. Application of the restricted cubic spline regression model revealed a non-linear relationship between aRTD and survival/radiotoxicity. Linear regression analysis (LRA) was performed to evaluate correlations between LRFS and overall survival (OS)/ disease-free survival (DFS). Results: For patients staged T1−2N0, T1−2N1−3, T3−4N0, and T3−4N1−3, 5-year OS in PORT and non-PORT groups were 77.38% vs. 72.91%, p = 0.919, 52.35% vs. 46.60%, p = 0.032, 73.41% vs. 61.19%, p = 0.005 and 38.30% vs. 25.97%, p < 0.001. With aRTD escalation, hazard ratios (HRs) of OS/DFS declined until aRTD exceeded 50Gy, then increased, whereas that of LRFS declined until aRTD exceeded 50 Gy, then remained steady. HR of treatment-related mortality was stable until aRTD exceeded 50 Gy, then increased. LRA revealed strong correlations between LRFS and OS/DFS (r = 0.984 and r = 0.952, respectively). An absolute 1% advancement in LRFS resulted in 0.32% and 0.34% improvements in OS and DFS. Conclusions: An aRTD of 50Gy was well-tolerated, with favorable survival resulting from PORT-related LRFS improvement in patients staged T3−4N0 or T1-4N1−3. Further stratification analyses based on tumor burden would help determine potential PORT-beneficiaries.

[Characteristics and influencing factors of soil nitrification potential in coastal salinized farmland]. / æ»¨æµ·ç›æ¸å†œç”°åœŸå£¤ç¡åŒ–åŠ¿ç‰¹å¾åŠå ¶å½±å“å› ç´ .

Understanding the nitrification capacity of coastal saline farmland soils and its main drivers is of great significance to regulate soil nitrification and improve the utilization efficiency of nitrogen fertilization in farmland. Using a combination of field investigations and laboratory analyses, we examined farmland soil nitrification potential and soil physical, chemical, and biological properties in the coastal muddy tidal flat saline soil area (Dongying and Dongtai). We established the correlation between soil properties and soil nitrification potential with multiple stepwise regression analyses and structural equation modeling (SEM). The results showed that soil pH value was relatively stable and other soil properties and soil nitrification potential varied in coastal saline farmland. The soil nitrification potential ranged from 0.04 to 10.42 mg·kg-1·d-1 and decreased with the increases of soil salinization level. Soil nitrification potential had the strongest correlation with soil organic matter, cation exchange capacity, and Cl-, with the correlation coefficient being 0.409, 0.397 and -0.337, respectively. The results of multiple stepwise regression analysis showed that Na+, silt, cation exchange capacity, and CO32-+HCO3- were the main influencing factors of soil nitrification potential. The results from the SEM analysis suggested that Na+, silt, cation exchange capacity, and CO32-+HCO3- directly affected soil nitrification potential, and soil organic matter, clay, Cl- and SO42- had indirect effects. In all, soil Na+ and cation exchange capacity were the two main factors affecting nitrification. Adjusting soil NaCl content and cation exchange capacity was an effective means of regulating soil nitrification.

Study on strain sensing property of fiber Bragg grating based on surface strain measurement of mechanical structure.

Strain monitoring is of great significance to identify the failure of key mechanical components and ensure the good operation of mechanical equipment. In terms of the common issue of the low sensitivity of fiber Bragg grating (FBG) strain sensor in strain measurement on the mechanical structure surface, this paper describes a flexible hinge strain sensor with the FBG as the sensitive element. A theoretical analysis of the sensitivity of the sensor is performed, a copper alloy material with a large elastic modulus is selected, the simulation analysis and optimization design for the structural parameters of the sensor are carried out by using ANSYS and Solidworks software, then the object of the sensor is developed according to the simulation results, and finally, the performance of the sensor is tested. The results show that the maximum deformation the sensor can measure is 0.5299 µÎµ, the sensitivity of the sensor is ∼1.8870 pm/µÎµ, which is approximately twice that of the bare FBG sensor, the linearity is greater than 99%, and the relative standard deviation of the repeatability is 0.9%. The results of the study provide a reference for developing the optical fiber strain sensor and further improving its sensitivity.

Analysis on Recycling Channel Selection of Construction and Demolition Waste in China from the Perspective of Supply Chain.

Although construction and demolition waste (C&D waste) recycling has been widely regarded as an effective way to save resources, its selection of recycling channels has received little attention. In order to improve the recycling efficiency of C&D waste and promote the process of C&D waste management, we innovatively propose a dual-channel recycling problem of C&D waste from the perspective of supply-chain operation, aiming to study the impact of the selection of recycling channels and the government's economic intervention on pricing decisions. Specifically, we build in this paper a three-echelon construction material supply chain including a construction contractor, a professional recycling agency, and a building materials manufacturer, considering two modes: the construction contractor does the recycling job alone (as the direct channel) and the construction contractor entrusts the recycling job to the professional recycling agency (as the indirect channel). We use game theory to analyze the optimal decision strategies of the members with or without governmental intervention and the equilibrium strategies are obtained. At the same time, taking Chongqing city as an example, we apply the model to carry out numerical simulation, and the results reveal that greater recycling costs of C&D waste leads to lower profits for the members. When the market capacity of first-class renewable building materials increases, the recycler's recycling cost of C&D waste decreases, and the remanufacturing cost of recycled materials processed into first-class renewable building materials decreases, the supply-chain members will choose the indirect channel to perform the recycling job. In the case when government intervention exists, the recycling quantity of C&D waste increases, the price of the final products decreases, and both the total profit of the system and the profit of the supply-chain members increase; there is a positive correlation with the government subsidies. The study provides some insights on managerial significance to C&D waste recycling management.

Biochar Addition Inhibits Nitrification by Shifting Community Structure of Ammonia-Oxidizing Microorganisms in Salt-Affected Irrigation-Silting Soil.

Biochar has been widely recognized as an effective and eco-friendly ameliorant for saline soils, but information about the mechanism of how biochar influences nitrification in salt-affected agroecosystem remains fragmented. An incubation experiment was performed on the salt-affected soil collected from a three-consecutive-year experiment at biochar application gradients of 7.5 t⋅ha-1, 15 t⋅ha-1 and 30⋅t ha-1 and under nitrogen (N) fertilization. Responses of the nitrification rate (NR), numbers of ammonia monooxygenase (amoA) gene copies, and community structures of ammonia-oxidizing bacteria (AOB) and archaea (AOA) to biochar application were investigated. The results indicated that, under N fertilization, the NR and numbers of amoA-AOB and amoA-AOA gene copies negatively responded to biochar addition. Biochar application increased the community diversity of AOB but decreased that of AOA. Biochar addition and N fertilization shifted the AOB community from Nitrosospira-dominated to Nitrosospira and Nitrosomonas-dominated, and altered the AOA community from Nitrososphaera-dominated to Nitrososphaera and Nitrosopumilus-dominated. The relative abundance of Nitrosospira, Nitrosomonas and Nitrosopumilus decreased, and that of Nitrosovibrio and Nitrososphaera increased with biochar application rate. Soil SOC, pH and NO3--N explained 87.1% of the variation in the AOB community, and 78.1% of the variation in the AOA community was explanatory by soil pH and SOC. The SOC and NO3--N influenced NR through Nitrosovibrio, Nitrosomonas, Norank_c_environmental_samples_p_Crenarchaeota and amoA-AOB and amoA-AOA gene abundance. Therefore, biochar addition inhibited nitrification in salt-affected irrigation-silting soil by shifting the community structures of AOB and AOA and reducing the relative abundance of dominant functional ammonia-oxidizers, such as Nitrosospira, Nitrosomonas and Nitrosopumilus.

Role of the CBX Molecular Family in Lung Adenocarcinoma Tumorigenesis and Immune Infiltration.

Background: The members of the Chromobox (CBX) family are important epigenetic regulatory molecules with critical biological roles in many tumors. However, no study has analyzed or verified their role in lung adenocarcinoma (LUAD). Methods: UALCAN and Oncomine databases were used to analyze CBX expression in LUAD, and the cBioPortal database was used to analyze CBX genetic variations. The Kaplan-Meier plotter and UALCAN databases were used to identify molecules with prognostic value. Gene Ontology pathway, receiver operating characteristic curves, and tumor-infiltrating immune cell analyses were used to clarify the biological function of the CBX hub molecules. Paired tumor samples and lung adenocarcinoma cell lines were collected for molecular functional assays to validate the results of the bioinformatics analysis. Results: CBX3/5 may have a cancer-promoting effect and its expression is associated with a poor patient prognosis, while CBX7 shows an opposite trend. CBX3/5/7 can regulate signaling pathways, regulate tumor immune cell infiltration, and has diagnostic value. Molecular biology experiments show that CBX3/5 is highly expressed in LUAD patients; in vitro it promotes the proliferation and migration of the LUAD cell line and can regulate the expression of the corresponding cytokines. CBX7 has opposite effects. Conclusion: Our bioinformatics analysis and subsequent experimental verification confirmed the CBX family members acted as hub signaling molecules in LUAD. The results provide new potential targets for the diagnosis and treatment of this cancer.

Belantamab Mafodotin (GSK2857916) Drives Immunogenic Cell Death and Immune-mediated Antitumor Responses In Vivo.

B-cell maturation antigen (BCMA) is an attractive therapeutic target highly expressed on differentiated plasma cells in multiple myeloma and other B-cell malignancies. GSK2857916 (belantamab mafodotin, BLENREP) is a BCMA-targeting antibody-drug conjugate approved for the treatment of relapsed/refractory multiple myeloma. We report that GSK2857916 induces immunogenic cell death in BCMA-expressing cancer cells and promotes dendritic cell activation in vitro and in vivo GSK2857916 treatment enhances intratumor immune cell infiltration and activation, delays tumor growth, and promotes durable complete regressions in immune-competent mice bearing EL4 lymphoma tumors expressing human BCMA (EL4-hBCMA). Responding mice are immune to rechallenge with EL4 parental and EL4-hBCMA cells, suggesting engagement of an adaptive immune response, immunologic memory, and tumor antigen spreading, which are abrogated upon depletion of endogenous CD8+ T cells. Combinations with OX40/OX86, an immune agonist antibody, significantly enhance antitumor activity and increase durable complete responses, providing a strong rationale for clinical evaluation of GSK2857916 combinations with immunotherapies targeting adaptive immune responses, including T-cell-directed checkpoint modulators.

Nitrate leaching and NH3 volatilization during soil reclamation in the Yellow River Delta, China.

The agricultural ecological system is an important part of the Yellow River Delta (YRD); however, soil reclamation may trigger environmental concerns about nitrate leaching and NH3 volatilization in this area. To assess nitrogen losses during soil reclamation, a two-year field experiment was conducted with plastic film mulch, which is an effective way to alleviate water-salt stress. The Hydrus-2D software package was used to calculate nitrogen transport, transformation and losses. The results showed that nitrogen (N) retention in the soil varied during the two growing seasons, because soil water, salinity and climatic conditions acted together on nitrogen transport and transformation. Soil salinity promoted NH3 volatilization, and the proportions of ammonia volatilization were 22.78 percent and 19.50 percent of the N input in 2018 and 2019, respectively, because urea hydrolysis, nitrification and soil NH4+-N adsorption capacity were limited by soil salt. NO3--N leaching was controlled by soil water infiltration, climatic conditions and groundwater level. NO3--N leaching was 43.84 percent and 32.89 percent of the nitrogen input in 2018 and 2019, respectively; the difference was mainly caused by the different distribution of rainfall during the growing season; thus, soil water infiltration increased under heavy rainfall because it broke the barrier formed by the plough pan. This study indicates that there is a risk of nitrogen pollution during soil reclamation. In addition, Hydrus-2D has considerable potential to calculate nitrogen losses under the effect of plastic film mulch in this area.

Comparison of Muscle Density in Middle-Aged and Older Chinese Adults Between a High-Altitude Area (Kunming) and a Low-Altitude Area (Beijing).

Background and Purpose: A high-altitude environment was known to have a negative effect on bone and lead to a higher incidence of hip fracture. However, the dependence of muscle composition on altitude is unclear. Thus, we aimed to compare muscle density and area in plateau and low altitude area and to determine the effect of the altitude on these outcomes. Methods: Community dwelling adults over 60 years old living in Beijing (elevation 50 m; 300 subjects,107 men and 193 women) or Kunming (elevation 2000 m; 218 subjects,83 men and 135 women) for more than 10 years were enrolled. Quantitative CT was performed in all subjects and cross-sectional area and attenuation measured in Hounsfield units (HU) were determined for the trunk, gluteus, and mid-thigh muscles. Results: Compared to Beijing, Kunming adults were slimmer (Beijing men vs Kunming men: 25.08 ± 2.62 vs 23.94 ± 3.10kg/m2, P=0.013; Beijing women vs Kunming women: 25.31 ± 3.1 vs 23.98 ± 3.54 kg/m2, P= 0.001) and had higher muscle density in the L2-trunk and gluteus maximus muscles after adjustment for age and BMI (L2-trunk muscles: Beijing men 29.99 ± 4.17 HU vs Kunming men 37.35 ± 4.25 HU, P< 0.0001; Beijing women 27.37 ± 3.76 HU vs Kunming women 31.51 ± 5.12 HU, P< 0.0001; Gluteus maximus muscle: Beijing men 35.11 ± 6.54 HU vs Kunming men 39.36 ± 4.39 HU, P= 0.0009; Beijing women 31.47 ± 6.26 HU vs Kunming women 34.20 ± 5.87 HU P=0.0375). Age was similar in both cohorts and no differences were observed in the gluteus medius and minimus muscle or the mid-thigh muscle, either in the area or density. Conclusions: Compared with Beijing, the adults in Kunming had higher muscle density of the gluteus maximus and L2 trunk muscles, showing that living at a higher altitude might be beneficial to muscle quality.

[Influencing mechanism of soil salinization on nitrogen transformation processes and efficiency improving methods for high efficient utilization of nitrogen in salinized farmland]. / ç›æ¸åŒ–å¯¹å†œç”°æ°®ç´ è½¬åŒ–è¿‡ç¨‹çš„å½±å“æœºåˆ¶å’Œå¢žæ•ˆè°ƒæŽ§é€”å¾„.

Based upon the review of the status of nitrogen use efficiency in salinized farmland in China, we summarized the effect of salinization on key processes of nitrogen transformation in farmland soil, analyzed the microbial mechanism underlying nitrogen transformation, and summed up the main ways for high efficient utilization of nitrogen in salinized farmland. Salinization had thre-shold effects on mineralization, nitrification, and denitrification of nitrogen from farmland soil, with the influence varying greatly in different scopes. Salinity and secondary barriers had different effects on microorganisms, with threshold in their effects. The most widely used methods for nitrogen synergism regulation in salinized farmland include soil conditioner, biomass material, growing salt-tole-rant plants, optimizing the ratio of different nitrogen forms, and biological inhibitor. We proposed current research shortcomings and future research directions of nitrogen cycle processes in salinized farmland. This study was of great significance for reducing nitrogen loss, enhancing utilization of nutrient from fertilizers, and controlling agricultural non-point source pollution in salinized farmland.

Biochar and fulvic acid amendments mitigate negative effects of coastal saline soil and improve crop yields in a three year field trial.

China with large area of land planted with crops are suffering secondary salinization in coastal area for the lack of fresh water and saltwater intrusion to the groundwater. The purpose of this study was to investigate the effects of biochar (BC) and fulvic acid (FA) on the amelioration of coastal saline soil and their impact on crop yields under maize-barley rotation system. A three year field experiment was conducted in a saline soil on a farm in coastal area of east Jiangsu Province, China. A maize-barley rotation system had been carried out for ten years with local conventional management before the experiment. The saline soil was amended with BC at rates of 0, 7.5 t ha-1 (BC1), 15 t ha-1 (BC2) and 30 t ha-1 (BC3) alone or combined with fulvic acid (1.5 t ha-1) compared with control. Fertilizers were applied under normal planting strategies. The BC was added only once during the four growing seasons, and the FA was applied before each sowing. Soil salinity changed significantly during the three year field experiment. This was mainly due to the great quantity of rain during the period of maize cultivation. Although Na+, Cl- and SO42- in BC and /or FA treatments significantly decreased, the pH value increased up to 9.0 as the CO32- + HCO3-content increased. Total organic carbon (TOC) and phosphorus (TP) responded positively to biochar addition rate. BC applied with appropriate rate at 15 t ha-1 (BC2) in combination with FA showed optimal effects on soil salinity amelioration, soil physics properties regulation, soil nutrition improvement and crop yields increase. The TOC and TP was 5.2 g kg-1 and 507 mg kg-1 in BC2 + FA treatment, which were lower than BC3 and BC3 + FA treatments. However, the highest total grain yield was obtained in the BC2 + FA treatment, and the total yield was increased by 62.9% over the CK. This study emphasizes that using combined organic amendment of BC with FA for profitable and sustainable use of salt-affected soils would be practicable.