Developmental Stage-Specific Imprinting of IPL in Domestic Pigs (Sus scrofa)

Imprinted in placenta and liver (IPL) gene has been identified as an imprinted gene in the mouse and human. Its sequence and imprinting status, however, have not been determined in the domestic pigs. In the present study, a 259 base pair-specific sequence for IPL gene of the domestic pig was obtained and a novel SNP, a T/C transition, was identified in IPL exon 1. The C allele of this polymorphism was found to be the predominant allele in Landrace,Yorkshire, and Duroc. The frequency of CC genotype and C allele are different in Duroc as compared with Yorkshire (P = .038 and P = .005, resp.). Variable imprinting status of this gene was observed in different developmental stages. For example, it is imprinted in 1-dayold newborns (expressed from the maternal allele), but imprinting was lost in 180-day-old adult (expressed from both parental alleles). Real-time PCR analysis showed the porcine IPL gene is expressed in all tested eight organ/tissues. The expression level was significantly higher in spleen, duodenum, lung, and bladder of 180-day-old Lantang adult compared to that in 1-day-old newborns Lantang pigs (P < .05). In conclusion, the imprinting of the porcine IPL gene is developmental stage and tissue specific

First-principles study of O-2 activation on ligand-protected Au-32 clusters

NSFC [20873088]; Open Funds of State Key Laboratory of Physical Chemistry of Solid Surfaces (Xiamen University) [201109]; Fundamental Research Funds for the Central Universities, Southwest University for Nationalities [11NZYBS07]Poly(N-vinyl-2-pyrrolidone) (PVP) is often used to protect active Au clusters from coalescence. The influences of PVP on the O-2 adsorption on Au-32 clusters were investigated using density functional theory calculations. Various low-lying structures of O-2:Au-32 and O-2:Au-32:PVP complexes, in which the Au-32 is either neutral or anionic and the O-2 is either molecular or dissociative, were identified. The PVP influences were evaluated in terms of the changes in geometry, adsorption energy, charge redistribution, spin density, and density of states upon PVP pre-adsorption. Our calculations reveal that PVP weakly adsorbs on the cluster surface, with rather small changes in the structural, geometrical and electronic properties that are relevant to the O-2 activation. The activity of neutral or anionic Au-32 towards O-2 is kept or slightly enhanced by PVP because of the cooperative adsorption of PVP and O-2. This is the structural basis of choosing PVP as the protective ligand for Au clusters

Microbial regulation of aggregate stability and carbon sequestration under long-term conservation tillage and nitrogen application

peer reviewedThe stability of aggregates plays a significant role in soil organic carbon (SOC) sequestration in conservation agriculture soils. However, the regulation of microorganisms within aggregates on aggregate stability and SOC sequestration remains elusive. By dividing the soil into three aggregate size classes [mega-aggregates (>2000 μm), macro-aggregates (250–2000 μm), and micro-aggregates (<250 μm)], we evaluated the response of aggregate stability, SOC and microbial communities within aggregates to long-term conservation tillage, which consisted of two tillage methods (conventional tillage and no-tillage) and three nitrogen application rates (105, 180, and 210 kg N ha−1). Under no-tillage treatment, high nitrogen application rate increased SOC by 2.1–3.7 g·kg−1 within mega- and macro-aggregates but reduced the total amount of phospholipid fatty acids (PLFAs) within all aggregates. Under conventional tillage, high N application rate increased mean weight diameter (MWD) and reduced total PLFAs within all aggregates only in 0–10 cm. With the same nitrogen application rate, no-tillage increased MWD by 8.7 %–42.7 %, SOC content within mega-aggregates by 7.3 %–27.8 % and within macro-aggregates by 13.2 %–28.3 % when compared with conventional tillage. Actinobacteria were recruited by straw under no-tillage and their biomass increased 1.5–7.8 times in all aggregates compared with conventional tillage, where they might participate in aggregate formation via degradation of straw and increasing SOC within mega- and macro-aggregates. Conversely, desulfovibrio biomass within all aggregates was diminished under no-tillage compared with conventional tillage, while desulfovibrio possibly directly inhibited soil aggregate formation and decreased SOC within mega- and macro-aggregates under conventional tillage. Moreover, under no-tillage, arbuscular mycorrhizal fungi biomass increased by 0.4–1.6 nmol g−1 within all aggregates compared with conventional tillage in 0–10 cm, potentially indirectly contributing to soil aggregate formation via co-metabolic processes and increasing SOC within mega- and macro-aggregates. Overall, high nitrogen application under long-term no-tillage protects SOC within mega-aggregates by altering aggregate formation through the microbial communities, providing information that may be useful in developing management strategies to enhance carbon sequestration in agricultural soils

Negative pressure irrigation increases vegetable water productivity and nitrogen use efficiency by improving soil water and NO3–-N distributions

peer reviewedNegative pressure irrigation (NPI), which is a new subsurface irrigation technique, promotes vegetable yield, water productivity (WP), and nitrogen use efficiency (NUE). However, it is not clear how NPI improves vegetable growth, especially in terms of water supply characteristics and uniformities of soil water and nitrogen. In this study, a cucumber pot experiment that had 0 kPa (PW1), –5 kPa (PW2), –10 kPa (PW3), –15kPa (PW4), and traditional irrigation (PCK) treatments under nitrogen application (N1) and no application (N0) was conducted to reveal the water supply characteristics of NPI and its effect on vegetable growth. There are two main water supply characteristics: 1) automatically supplying irrigation water based on the consumption of soil water, and 2) keeping soil water content stable during the vegetable growth period. In addition, the relationship between vegetable growth and soil water and NO3–-N distribution uniformities throughout the soil profile was investigated by carrying out two tomato field experiments. The treatments of one tomato experiment were NPI with –5 kPa (F1W) and furrow irrigation (F1CK). We also carried out NPI with –5 kPa (F2W), furrow irrigation (F2CK), and drip irrigation (F2D) in another tomato experiment. The results showed that cumulative water application under N1 was higher than under N0 in the PW1, PW2, and PW3 treatments in the cucumber experiment. Volumetric soil water content under the NPI system was more stable during the vegetative growth period than under traditional irrigation. The NPI system also increased yields under appropriate pressures (–10–0 kPa) compared to the PCK treatment in the cucumber experiment. The NPI in the two tomato experiments reduced fertilizer inputs and irrigation compared to furrow irrigation and drip irrigation. However, the irrigation method had no significant influence on the tomato yield in the two tomato experiments. © 2021 Elsevier B.V

Nitrogen addition mediates the effect of soil microbial diversity on microbial carbon use efficiency under long-term tillage practices

peer reviewedTillage practices can influence soil microbial carbon use efficiency (CUE), which is critical for carbon cycling in terrestrial ecosystems. The effect of tillage practices could also be regulated by nitrogen (N) addition. However, the soil microbial mechanism relating to N fertilizer effect on microbial CUE under no-tillage (zero-tillage) is still unclear. We investigated how N fertilizer regulates the effect of tillage management on microbial CUE through changing microbial properties and further assessed the impact of microbial CUE on particulate (POC) and mineral-associated organic matter carbon (MAOC). For this we used a 16-year field experiment with no-tillage (NT) and conventional tillage (CT), both of which combined with 105 (N1), 180 (N2), and 210 kg N ha−1 (N3) N application. We found that microbial CUE increased with increasing N application rate. NT increased microbial CUE compared with CT in the 0–10 cm. The bacterial and fungal diversities of NT were higher than CT and N application decreased their diversities in 0–10 cm. The partial least squares path model showed that bacterial and fungal diversity had a significant influence on microbial CUE. Furthermore, POC and MAOC under NT were higher than CT and they also increased with increasing N application rate. It suggested that increasing microbial CUE induced by N application had the potential to increase POC and MAOC. Overall, this study highlights that N addition can alter the effect of soil microbial diversity on CUE, which further improves our understanding to explain and predict the fractions of SOC (i.e., POC and MAOC) in tillage systems

The dominant microorganisms vary with aggregates sizes in promoting soil carbon accumulation under straw application

peer reviewedUnraveling the influence of microbes on C content at aggregate scale is pivotal for promoting soil C accumulation. Previous studies were based mainly on the mutual transformation process between aggregates, the links between the microorganisms in initial aggregates and inner C content and aggregate sizes were still unclear. In this study, the classified aggregates (> 5 mm, 2–5 mm, 1–2 mm, 0.25–1 mm, and 2 mm aggregates. Aggregates of > 5 mm were more capable of improving unstable C accumulation and C derived from straw (Cstraw) than smaller aggregates. Fungi and Gram-negative bacteria (G-) were more important to increasing C accumulation in > 2 mm aggregates, whereas Gram-positive (G+) bacteria dominated in < 2 mm aggregates. The results indicate that the contribution of microorganisms within aggregates to inner C accumulation was associated with aggregate sizes. © 2021 Informa UK Limited, trading as Taylor & Francis Group

Macrophage polarization states in atherosclerosis

Atherosclerosis, a chronic inflammatory condition primarily affecting large and medium arteries, is the main cause of cardiovascular diseases. Macrophages are key mediators of inflammatory responses. They are involved in all stages of atherosclerosis development and progression, from plaque formation to transition into vulnerable plaques, and are considered important therapeutic targets. Increasing evidence suggests that the modulation of macrophage polarization can effectively control the progression of atherosclerosis. Herein, we explore the role of macrophage polarization in the progression of atherosclerosis and summarize emerging therapies for the regulation of macrophage polarization. Thus, the aim is to inspire new avenues of research in disease mechanisms and clinical prevention and treatment of atherosclerosis