Aridity affects soil organic carbon concentration and chemical stability by different forest types and soil processes across Chinese natural forests.

Forest soils play a critical role in carbon (C) reservoirs and climate change mitigation globally. Exploring the driving factors of soil organic carbon (SOC) concentration and stability in forests on a large spatial scale can help us evaluate the role of forest soils in regulating C sequestration. Based on SOC quantification and solid-state 13C nuclear magnetic resonance spectroscopy, we investigated the SOC concentration and SOC chemical stability (indicated by alkyl-to-O-alkyl ratio and hydrophobic-to-hydrophilic ratio) in top 0-5 and 5-10 cm soils from 65 Chinese natural forest sites and explored their driving factors. Results showed that SOC concentration in 0-5 cm soils were highest in mixed forests but SOC chemical stability in 0-5 cm soils were highest in coniferous forests, while SOC concentration and chemical stability in 5-10 cm soil layers did not differ across forest types. SOC concentration in 0-5 cm was directly related to soil pH and soil bacterial diversity. Structural equation models showed that aridity indirectly affected SOC concentration in 0-5 cm by directly affecting soil pH. While SOC chemical stability in 0-5 cm soils was higher with increased aridity. According to the correlations, the potential mechanisms could be attributed to higher proportion of coniferous forests in more arid forest sites, lower relative abundance of O-alkyl C, higher MgO and CaO contents, and higher bacterial diversity in soils from more arid forest sites. Our study reveals the important role of aridity in mediating SOC concentration and chemical stability in top 0-5 cm soils in Chinese natural forests on a large-scale field investigation. These results will help us better understand the different mechanisms underlying SOC concentration and stability in forests and assess the feedback of forest SOC to future climate change.

Evodiamine Relieve LPS-Induced Mastitis by Inhibiting AKT/NF-κB p65 and MAPK Signaling Pathways.

Evodiamine, an alkaloid component in the fruit of Evodia, has been shown to have biological functions such as antioxidant and anti-inflammatory. But whether evodiamine plays an improvement role on mastitis has not been studied. To investigate the effect and mechanism of evodiamine on lipopolysaccharide (LPS)-induced mastitis was the purpose of this study. In animal experiments, the mouse mastitis model was established by injecting LPS into the canals of the mammary gland. The results showed that evodiamine could significantly relieve the pathological injury of breast tissue and the production of pro-inflammatory cytokines and inhibit the activation of inflammation-related pathways such as AKT, NF-κB p65, ERK1/2, p38, and JNK. In cell experiments, the mouse mammary epithelial cells (mMECs) were incubated with evodiamine for 1 h and then stimulated with LPS. Next, pro-inflammatory mediators and inflammation-related signal pathways were detected. As expected, our results showed that evodiamine notably ameliorated the inflammatory reaction and inhibit the activation of related signaling pathways of mMECs. All the results suggested that evodiamine inhibited inflammation by inhibiting the phosphorylation of AKT, NF-κBp65, ERK1/2, p38, and JNK thus the LPS-induced mastitis was ameliorated. These findings suggest that evodiamine maybe a potential drug for mastitis because of its anti-inflammatory effects.

A pH/redox-dual responsive, nanoemulsion-embedded hydrogel for efficient oral delivery and controlled intestinal release of magnesium ions.

It remains a major challenge to achieve efficient oral delivery and controlled intestinal release of ions using hydrogels. Herein, we report a novel, pH/redox-dual responsive, nanoemulsion-embedded composite hydrogel to address this issue. The hydrogel was first synthesized by crosslinking a biocompatible, pH-responsive pseudopeptide, poly(l-lysine isophthalamide) (PLP), and redox-sensitive l-cystine dimethyl ester dihydrochloride (CDE). A suitable amount of magnesium acetate was encapsulated into oil-in-water nanoemulsions, which were then embedded into the lysine-based hydrogel. The resulting composite hydrogel collapsed into a compact structure at acidic gastric pH, but became highly swollen or degraded in the neutral and reducing intestinal environment. The ion release profiles indicated that the nanoemulsion-embedded composite hydrogel could well retain and protect magnesium ions in the simulated gastric fluid (SGF) buffer at pH 1.2, but efficiently release them in the simulated intestinal fluid (SIF) buffer at pH 6.8 in the presence of 1,4-dithiothreitol (DTT) as a reducing agent. Moreover, this composite hydrogel system displayed good biocompatibility. These results suggested that the pH/redox-dual responsive, nanoemulsion-embedded composite hydrogel could be a promising candidate for efficient oral delivery and controlled intestinal release of magnesium and other ions.

Rumen-bypassed tributyrin alleviates heat stress by reducing the inflammatory responses of immune cells.

Heat stress (HS) in summer will seriously affect the health and performance of dairy cows. To alleviate the injury to dairy cows caused by HS, we added the rumen-bypassed tributyrin to the feed. We determined whether cows were in a heat-stressed environment by testing the temperature humidity index in the morning, at noon, and in the evening. The detection of anal temperature and respiratory frequency further proved the HS state of the dairy cows. The quantificational real time PCR results showed that tributyrin could significantly reduce the relative expression of tumor necrosis factor α, interleukin 1ß, and Interleukin 6. Western blot results showed that tributyrin could alleviate the lymphocyte inflammatory response by inhibiting the mitogen-activated protein kinase and nuclear factor-кB signaling pathways. To further detect the effect of tributyrin on HS in dairy cows, routine biochemical and blood tests were carried out. The results showed that the contents of aspartate aminotransferase, total bilirubin, creatinine, albumin, and globulin were significantly reduced by tributyrin. The results showed that tributyrin could significantly alleviate the liver and kidney injury induced by heat stress in dairy cows. Moreover, tributyrin could also significantly reduce the numbers of intermediate cells and increase the level of hemoglobin. Tributyrin could also improve the performance of dairy cows. These results suggested that tributylglycerol may have a positive effect on breast health of dairy cows. In conclusion, these results indicated that tributyrin could relieve HS and increase the production performance of dairy cows by reducing the inflammatory responses of lymphocytes.

Featured services and performance of BDS-3.

BeiDou Global Navigation Satellite System (BDS-3) not only performs the normal positioning, navigation and timing (PNT) functions, but also provides featured services, which are divided into geostationary orbit (GEO) and medium earth orbit (MEO) satellite-based featured services in this paper. The former refers to regional services consisting of the regional short message communication service (RSMCS), the radio determination satellite service (RDSS), the BDS satellite-based augmented service (BDSBAS) and the satellite-based precise point positioning service via B2b signal (B2b-PPP). The latter refers to global services consisting of the global short message communication service (GSMCS) and the MEO satellite-based search and rescue (MEOSAR) service. The focus of this paper is to describe these featured services and evaluate their performances. The results show that the inter-satellite link (ISL) contributes a lot to the accuracy improvement of orbit determination and time synchronization for the whole constellation. Compared with some other final products, the root mean squares (RMS) of the BDS-3 precise orbits and broadcast clock are 25.1 cm and 2.01 ns, respectively. The positioning accuracy of single frequency is better than 6 m, and that of the generalized RDSS is usually better than 12 m. For featured services, the success rates of RSMCS and GSMCS are better than 99.9% and 95.6%, respectively; the positioning accuracies of single and dual frequency BDSBAS are better than 3 and 2 m, respectively; the positioning accuracy of B2b-PPP is better than 0.6 m, and the convergence time is usually smaller than 30 min; the single station test shows that the success rate of MEOSAR is better than 99%. Due to the ISL realization in the BDS-3 constellation, the performance and capacities of the global featured services are improved significantly.

Dioscin Improves Pyroptosis in LPS-Induced Mice Mastitis by Activating AMPK/Nrf2 and Inhibiting the NF-κB Signaling Pathway.

Dioscin, a natural steroid saponin, has been shown to have anti-inflammatory effects, but its protective mechanism against mastitis is still unknown. NLRP3 inflammasome and pyroptosis play important roles in the pathogenesis of many inflammatory diseases, including mastitis. The purpose of this study was to explore the effect of dioscin on lipopolysaccharide- (LPS-) induced mastitis in vivo and in vitro and its mechanism of action. In vivo experiments, dioscin can reduce the inflammatory lesions and neutrophil motility in mammary tissue. Moreover, dioscin also can reduce the production of proinflammatory factors such as interleukin-1 beta (IL-1ß) and inhibit the activation of NLRP3 inflammasome in LPS-induced mice mastitis. In vitro experiments, the results showed that dioscin inhibited the inflammatory response and the activation of NLRP3 inflammasome, but the survival rate of mouse mammary epithelial cells (mMECs) induced by LPS+ATP is increased. Subsequently, the experiment convinces that dioscin can reduce LPS+ATP-induced mMEC pyroptosis by adding Ac-DEVD-CHO (a caspase-3 inhibitor). Further mechanistic studies demonstrate that dioscin can activate AMPK/Nrf2 to inhibit NLRP3/GSDMD-induced mMEC pyroptosis. In summary, this paper reveals a novel function of dioscin on mMEC pyroptosis and provides a new potential therapy of dioscin for the treatment and prevention of mastitis.