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1.
J Sci Food Agric ; 2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38523343

RESUMO

BACKGROUND: Optimizing biochar application is vital for enhancing crop production and ensuring sustainable agricultural production. A 3-year field experiment was established to explore the effects of varying the biochar application rate (BAR) on crop growth, quality, productivity and yields. BAR was set at 0, 10, 50 and 100 t ha-1 in 2018; 0, 10, 25, 50 and 100 t ha-1 in 2019; and 0, 10, 25 and 30 t ha-1 in 2020. Crop quality and growth status and production were evaluated using the dynamic technique for order preference by similarity to ideal solution with the entropy weighted method (DTOPSIS-EW), principal component analysis (PCA), membership function analysis (MFA), gray relation analysis (GRA) and the fuzzy Borda combination evaluation method. RESULTS: Low-dose BAR (≤ 25 t ha-1 for cotton; ≤ 50 t ha-1 for sugar beet) effectively increased biomass, plant height, leaf area index (LAI), water and fertility (N, P and K) productivities, and yield. Biochar application increased the salt absorption and sugar content in sugar beet, with the most notable increases being 116.45% and 20.35%, respectively. Conversely, BAR had no significant effect on cotton fiber quality. The GRA method was the most appropriate for assessing crop growth and quality. The most indicative parameters for reflecting cotton and sugarbeet growth and quality status were biomass and LAI. The 10 t ha-1 BAR consistently produced the highest scores and was the most economically viable option, as evaluated by DTOPSIS-EW. CONCLUSION: The optimal biochar application strategy for improving cotton and sugar beet cultivation in Xinjiang, China, is 10 t ha-1 biochar applied continuously. © 2024 Society of Chemical Industry.

2.
Sci Total Environ ; 905: 166917, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37704128

RESUMO

Although organic fertilizers played an important role in enhancing crop yield and soil quality, the effects of organic fertilizers replacing chemical fertilizers on greenhouse gas (GHG) emissions remained inconsistent, and further impeding the widespread adoption of organic fertilizers. Therefore, a global meta-analysis used 568 comparisons from 137 publications was conducted to evaluate the responses of GHG emissions to organic fertilizers replacing chemical fertilizers. The results indicated that organic fertilizers replacing chemical fertilizers significantly decreased N2O emissions, but increasing global warming potential (GWP) by enhancing CH4 and CO2 emissions. When replacing chemical fertilizers with organic fertilizers, a variety of factors such as climate conditions, soil conditions, crop types and agricultural practices influenced the GHG emissions and GWP. Among these factors, fertilizer organic C and available N level were the main factors affecting GHG and GWP. However, considering the feasibility and ease of optimizing these factors, fertilizer organic C, C/N and N substitution rate showed a more favorable choice for GWP reduction, and their interactions significantly affecting GWP. Moreover, considering the distinct GHG emissions patterns in dryland and paddy field, the analysis of optimizing GWP based on fertilizer organic C, C/N and N substitution rate was separately conducted. According to the simulation optimization, the optimal combination of fertilizer organic C (137.2-228.8 g·kg-1), C/N (6.9-52.0) and N substitution rate (20.0-22.5 %) effectively suppressed the extent of increase in GWP in paddy field compared with chemical fertilizers. In dryland, optimizing fertilizer organic C (100-278 g·kg-1), C/N (70.7-76.6) and N substitution rate (10.2-16.0 %) led to a reduction in GWP compared with chemical fertilizers, indicating that dryland are more suitable for promoting organic fertilizer application. In conclusion, this meta-analysis study quantitatively assessed the GHG emissions when organic fertilizers replacing chemical fertilizers, and also provided a scientific basis for the mitigation of GHG emissions by organic fertilizers management.

3.
Sensors (Basel) ; 23(18)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37765722

RESUMO

High-rise building fires pose a serious threat to the lives and property safety of people. The lack of reliable and accurate positioning means is one of the main difficulties faced by rescuers. In the absence of prior knowledge of the high-rise building fire environment, the coverage deployment of mobile base stations is a challenging problem that has not received much attention in the literature. This paper studies the problem of the autonomous optimal deployment of base stations in high-rise building fire environments based on a UAV group. A novel problem formulation is proposed that solves the non-line-of-sight (NLOS) positioning problem in complex and unknown environments. The purpose of this paper is to realize the coverage and deployment of mobile base stations in complex and unknown fire environments. The NLOS positioning problem in the fire field environment is turned into the line-of-sight (LOS) positioning problem through the optimization algorithm. And there are more than three LOS base stations nearby at any point in the fire field. A control law which is formulated in a mathematically precise problem statement is developed that guarantees to meet mobile base stations' deployment goals and to avoid collision. Finally, the positioning accuracy of our method and that of the common method were compared under many different cases. The simulation result showed that the positioning error of a simulated firefighter in the fire field environment was improved from more than 10 m (the positioning error of the traditional method) to less than 1 m.

4.
J Interv Cardiol ; 2022: 5451947, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36419957

RESUMO

Pulmonary hypertension (PH) is a type of clinical pathophysiological syndrome characterized by a progressive increase in pulmonary vascular resistance and subsequent progressive failure of the right heart function, and is a common complication of many diseases. Mesenchymal stem cells (MSCs) autonomously home to sites damaged by disease, repair damaged tissues, and participate in the regulation of systemic inflammation and immune responses, which have good clinical application prospects. Extracellular vesicles (EVs), such as exosomes and microvesicles, participate in various biological activities by regulating intercellular communication. Exosomes secreted into the extracellular environment also affect the host immune system. MSC-derived extracellular vesicles (MSC-EVs), as a mediator in the paracrine processes of MSCs, carry biologically active substances such as proteins, lipids, mRNA, and micro-RNA. MSC-EVs therapies, safer than cell-based treatments, have been shown to be effective in modulating macrophages to support anti-inflammatory phenotypes, which are strongly related to histological and functional benefits in preclinical models of pulmonary hypertension. The main effects of active substances and their potential medical value have attracted wide attention from researchers. This article reviews the role and relevant mechanisms of MSC-EVs in the treatment of pulmonary hypertension in recent studies and provides a basis for their future clinical applications.


Assuntos
Exossomos , Vesículas Extracelulares , Hipertensão Pulmonar , Células-Tronco Mesenquimais , MicroRNAs , Humanos , Hipertensão Pulmonar/terapia , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Células-Tronco Mesenquimais/metabolismo , Exossomos/metabolismo , MicroRNAs/metabolismo
5.
Sci Total Environ ; 771: 144802, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33736170

RESUMO

Biochar application has been a promising approach to improve soil quality but their optimal amount in improving physical and hydraulic properties remains contradictory and inconclusive. The objective of this study was to examine and propose an optimal biochar application amount in saline alkali soil considering their impact on soil physical and hydraulic properties. A three-year field experiment was conducted in the saline-alkali soils under plastic film-mulched drip irrigation in Xinjiang, China. The studied physical and hydraulic properties included bulk density, soil porosity, saturated soil water content (θs), permanent wilting point (PWP), field capacity (FC), plant available water (PAW), spatial distribution of soil water content, planar soil water storage (PSWS), and soil evaporation. The treatments included biochar application amounts of 0 (CK), 10 (B10), 50 (B50), and 100 t ha-1 (B100) in 2018. Additional two treatments with 25 t ha-1 (B25) and 30 t ha-1 (B30) were added in 2019 and 2020, respectively. A four-parameter Gaussian function was fitted to the single-peak curves of the studied hydraulic properties vs. biochar application amounts to determine the most optimal biochar application amount. The results indicated that: (1) All of the biochar treatments significantly decreased bulk density and increased soil porosity over CK; (2) B10 and B25 treatments significantly increased θs, FC, PAW, PWP, and PSWS of root zones in the film-mulched zones over CK, but reverse results were observed in the B50 and B100 treatments; (3) Daily and cumulative soil evaporation were increased in no mulch zones of all biochar treatments over CK; (4) A dose of 21.9 t ha-1 was recommended as the most optimal biochar application amount for improving physical and hydraulic properties of saline-alkali soil. This research provided useful information on biochar application amounts for improving physical and hydraulic properties in saline-alkali soil.


Assuntos
Álcalis , Solo , Carvão Vegetal , China
6.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 7): o2033, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22807859

RESUMO

The asymmetric unit of the title compound, C(44)H(32)P(2), conventionally abbreviated BINAP, is one half of the complete chiral BINAP mol-ecule, which adopts a C2 crystallographic point-group symmetry with a twofold axis splitting the mol-ecule in two identical halves; a center of symmetry between mol-ecules further determines the racemic pairs. There are no obvious supra-molecular inter-actions between adjacent BINAP mol-ecules.

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