Understanding the Mechanism of Urbanization Affect Agricultural Water Efficiency: Evidence from China

Concerns regarding food security and sustainable development have been highlighted as a result of water scarcity and growing urbanization. It is imperative to look into their relationship. This study examines the impact of urbanization on agricultural water efficiency (AWE) in China utilizing China province-level panel data from 2002 to 2019. The findings indicate that urbanization has a U-shaped relationship with AWE, meaning that urbanization first had a detrimental effect on AWE before reversing course. These findings are robust to the inclusion of three measures of urbanization and the estimation of the instrumental variable method. Structural equation modeling of the underlying mechanisms demonstrates that, at higher levels of urbanization, planting structure and irrigation facilities partially mediate the urbanization-AWE relationship; the mediate effects account for between 27.3% and 100% of total effects, depending on the urbanization measurement used. China should continue investing in rural irrigation infrastructure as it urbanizes, as this would improve water efficiency

Development of a chemical kinetic mechanism for ammonia/macromolecular hydrocarbon combustion

C-free fuel ammonia has a high auto-ignition temperature and low flame speed compared to conventional hydrocarbon fuels, which limits its application in internal combustion engines (ICEs). Blending ammonia (NH3) with a highly reactive fuel can effectively solve this problem, and traditional macromolecular hydrocarbon fuels are a good choice because of their practicality and economy. However, the chemical reaction mechanism for the combustion of NH3/macromolecular hydrocarbons is not yet fully understood. In this study, a detailed kinetic mechanism for NH3 and toluene reference fuel (TRF) is proposed with 250 species and 4272 reactions. The developed NH3/TRF mechanism was validated by a single component (NH3, n-heptane, iso-octane, and toluene) and multiple components (NH3/n-heptane, NH3/iso-octane, NH3/toluene) with ignition delay time, laminar burning velocity, and key intermediate component distribution. The current NH3/TRF mechanism showed good performance compared with previous mechanisms. The co-combustion of NH3/TRF blends was performed with different NH3 energy fractions, and sensitivity and reaction pathway analyses were performed to reveal the effect of TRF addition on NH3 combustion. The results showed that the OH radical is mainly produced through N-containing reactions rather than C-containing reactions under T = 1000 K, P = 40 atm, and ϕ = 1 with more than 30 % NH3 addition. The HO2 radical is the most important radical for NH3 ignition, in addition to OH radicals, and its reactions with N-containing radicals (NH2, H2NO, and NO) contribute to the majority of OH radicals

Three-dimensional reconstruction and growth factor model for rock cracks under uniaxial cyclic loading/unloading by X-ray CT

The spatial distribution and propagation of cracks are one of the key factors that can influence the initiation of rock failure. In this investigation, the technique of X-ray computed tomography (CT) scanning was used to survey the pattern of rock cracks during cyclic loading/unloading. The distribution and nonlinear development of rock cracks were explored by three-dimensional (3D) reconstruction for use to quantitatively describe their growth. An entropy model for rock mass and a crack growth factor model were established, which could help to reveal the relation between the crack propagation and the macroscopic destruction.The results showed that all disconnected cracks in two-dimensional (2D) images became connected with each other in 3D images. The fractal dimension of rock cracks was increasing first and then decreasing, which was the result of gradual transformation of rock cracks. The growth rate of cracks was decreased with the increase of the quantity of cracks, which was caused by the retardation. When the quantity of cracks grew to a maximal, the growth rate was reduced to zero.Published versio

Crop Productivity, Economic Advantage, and Photosynthetic Characteristics in a Corn-Peanut Intercropping System

Corn-peanut intercropping is an important element of China’s agricultural planting model as it confers ecological benefits and increases yield. The aim of this study was to explore the productivity differences between intercropping and monoculture by using the 13C isotope tracer labelling method. Corn hybrid Denghai 618 (DH618) and peanut variety Huayu 22 (HY22) were used as test materials under three planting methods, single corn, SM; single peanut, SP; and corn-peanut intercropping, IM and IP, respectively, during two growing seasons. The results showed that IM increased yield by 59.7% and 62.3% compared with SM, respectively. IP reduced yield by 31.3% and 32.3% compared with SP, respectively. IM significantly increased the photosynthetic rate, leaf area, 13C assimilation distribution, and dry matter accumulation of summer corn, which led to an increase in the kernel number and grain yield. The decrease in intercropped peanut yield was mainly caused by a decrease in the full-pod rate and number of pods per plant. The decrease in peanut yield did not affect the production of intercropping benefit due to the larger intercropping advantage and land equivalence ratio. Corn-peanut intercropping yielded greater economic benefits than monoculture. These results showed the utility of the peanut-corn intercropping model

Crop Productivity, Economic Advantage, and Photosynthetic Characteristics in a Corn-Peanut Intercropping System

Corn-peanut intercropping is an important element of China’s agricultural planting model as it confers ecological benefits and increases yield. The aim of this study was to explore the productivity differences between intercropping and monoculture by using the 13C isotope tracer labelling method. Corn hybrid Denghai 618 (DH618) and peanut variety Huayu 22 (HY22) were used as test materials under three planting methods, single corn, SM; single peanut, SP; and corn-peanut intercropping, IM and IP, respectively, during two growing seasons. The results showed that IM increased yield by 59.7% and 62.3% compared with SM, respectively. IP reduced yield by 31.3% and 32.3% compared with SP, respectively. IM significantly increased the photosynthetic rate, leaf area, 13C assimilation distribution, and dry matter accumulation of summer corn, which led to an increase in the kernel number and grain yield. The decrease in intercropped peanut yield was mainly caused by a decrease in the full-pod rate and number of pods per plant. The decrease in peanut yield did not affect the production of intercropping benefit due to the larger intercropping advantage and land equivalence ratio. Corn-peanut intercropping yielded greater economic benefits than monoculture. These results showed the utility of the peanut-corn intercropping model

Pseudouridine synthase 1 regulates erythropoiesis via transfer RNAs pseudouridylation and cytoplasmic translation

Summary: Pseudouridylation plays a regulatory role in various physiological and pathological processes. A prime example is the mitochondrial myopathy, lactic acidosis, and sideroblastic anemia syndrome (MLASA), characterized by defective pseudouridylation resulting from genetic mutations in pseudouridine synthase 1 (PUS1). However, the roles and mechanisms of pseudouridylation in normal erythropoiesis and MLASA-related anemia remain elusive. We established a mouse model carrying a point mutation (R110W) in the enzymatic domain of PUS1, mimicking the common mutation in human MLASA. Pus1-mutant mice exhibited anemia at 4 weeks old. Impaired mitochondrial oxidative phosphorylation was also observed in mutant erythroblasts. Mechanistically, mutant erythroblasts showed defective pseudouridylation of targeted tRNAs, altered tRNA profiles, decreased translation efficiency of ribosomal protein genes, and reduced globin synthesis, culminating in ineffective erythropoiesis. Our study thus provided direct evidence that pseudouridylation participates in erythropoiesis in vivo. We demonstrated the critical role of pseudouridylation in regulating tRNA homeostasis, cytoplasmic translation, and erythropoiesis

Luminescent property of La(OH)3: Eu3+ nanorod and its decomposed compounds of LaOOH and La2O3

In this work, aiming to evaluate and compare the luminescent property of Eu ^3+ doped La(OH) _3 nanorods and its decomposed compounds of LaOOH and La _2 O _3 , La(OH) _3 : Eu ^3+ nanorods were synthesized and the decomposition behaviors in air and hydrogen were revealed. Then the luminescent property of 0%–8% Eu ^3+ doped La(OH) _3 nanorods and the 300 °C–800 °C calcined La(OH) _3 : Eu ^3+ - 4% were studied. Results show that LaOOH is intermediate product during the degradation of La(OH) _3 in air or H _2 , which can be formed at a temperature range in 372.3 °C–592.9 °C in air. Intensity of emission spectra of La(OH) _3 : Eu ^3+ nanorods increases with the rising of Eu ^3+ dopant concentration, and the emission property of Eu ^3+ doped LaOOH and La _2 O _3 is varied and strengthened with that of La(OH) _3 : Eu ^3+ . Luminescent matrixes of LaOOH and La _2 O _3 show similar emission spectrum and intensity, and the transitions of the D _0  →  ^7 F _1 and D _0  →  ^7 F _2 of Eu ^3+ each bifurcate into two peaks for both europium (III) doped La _2 O _3 and LaOOH. The revealed results suggest that LaOOH is a relative thermal-stable compound and should be an appropriate matrix as similar as La _2 O _3 for luminescent applications

Maize/peanut intercropping increases photosynthetic characteristics, 13C-photosynthate distribution, and grain yield of summer maize

Intercropping is used widely by smallholder farmers in developing countries to increase land productivity and profitability. We conducted a maize/peanut intercropping experiment in the 2015 and 2016 growing seasons in Shandong, China. Treatments included sole maize (SM), sole peanut (SP), and an intercrop consisting of four rows of maize and six rows of peanut (IM and IP). The results showed that the intercropping system had yield advantages based on the land equivalent ratio (LER) values of 1.15 and 1.16 in the two years, respectively. Averaged over the two years, the yield of maize in the intercropping was increased by 61.05% compared to that in SM, while the pod yield of peanut was decreased by 31.80% compared to SP. Maize was the superior competitor when intercropped with peanut, and its productivity dominated the yield of the intercropping system in our study. The increased yield was due to a higher kernel number per ear (KNE). Intercropping increased the light transmission ratio (LTR) of the ear layer in the maize canopy, the active photosynthetic duration (APD), and the harvest index (HI) compared to SM. In addition, intercropping promoted the ratio of dry matter accumulation after silking and the distribution of 13C-photosynthates to grain compared to SM. In conclusion, maize/peanut intercropping demonstrated the potential to improve the light condition of maize, achieving enhanced photosynthetic characteristics that improved female spike differentiation, reduced barrenness, and increased KNE. Moreover, dry matter accumulation and 13C-photosynthates distribution to grain of intercropped maize were improved, and a higher grain yield was ultimately obtained

Six1

Molecular genetic changes in acute myeloid leukemia (AML) play crucial roles in leukemogenesis, including recurrent chromosome translocations, epigenetic/spliceosome mutations and transcription factor aberrations. Six1, a transcription factor of the Sine oculis homeobox (Six) family, has been shown to transform normal hematopoietic progenitors into leukemia in cooperation with Eya. However, the specific role and the underlying mechanism of Six1 in leukemia maintenance remain unexplored. Here, we showed increased expression of SIX1 in AML patients and murine leukemia stem cells (c-Kit cells, LSCs). Importantly, we also observed that a higher level of Six1 in human patients predicts a worse prognosis. Notably, knockdown of Six1 significantly prolonged the survival of MLL-AF9-induced AML mice with reduced peripheral infiltration and tumor burden. AML cells from Six1-knockdown (KD) mice displayed a significantly decreased number and function of LSC, as assessed by the immunophenotype, colony-forming ability and limiting dilution assay. Further analysis revealed the augmented apoptosis of LSC and decreased expression of glycolytic genes in Six1 KD mice. Overall, our data showed that Six1 is essential for the progression of MLL-AF9-induced AML via maintaining the pool of LSC