204 research outputs found
Diurnal and seasonal variations in soil respiration of four plantation forests in an urban park
Understanding the carbon dynamics of urban trees and forests is one of the key components for developing mitigation strategies for climate change in a fast-paced urbanized world. This study selected four plantation forests composed of poplar, black locust, Chinese pine and mixture of poplar and black locust, located in an urban forest park on a well-drained fluvial plain with same land-use history. The diurnal and seasonal changes in soil respiration (Rs) and biophysical factors were measured from April 2015 to March 2016. At the diurnal scale, Rs varied out of phase with soil temperature (Ts) and the time-lag occurred in May and July when Ts was relatively high and soil moisture (Ms) was low. Strong seasonal variations in Rs were mainly determined by Ts, while the growing-season mean Rs positively correlated with the fine root biomass (FRB), soil organic carbon content (SOC), and total nitrogen content (TN) for all the forests. FRB alone could explain 75% of the among-stand variability. This study concluded that urban forest plantations have similar soil respiration dynamics to forest ecosystems in non-urban settings
Effects of Saline and Alkaline Stresses on Growth and Physiological Changes in Oat (Avena sativa L.) Seedlings
Two neutral salts (NaCl and Na2SO4) and alkaline salts (NaHCO3 and Na2CO3) were both mixed in 2:1 ratio, and the effects of saline and alkaline stresses on growth and physiological changes in oat seedlings were explored. The result showed that biomass, water content and chlorophyll content decreased while cell membrane permeability significantly increased under alkaline stress. Saline stress did not have an obvious effect on pH value in tissue fluids of shoot and root, but alkaline stress increased pH value in the root tissue fluid. The contents of Na+, Na+/K+, SO42- increased more, and K+, NO3-, H2PO4- decreased more under alkaline stress, the Cl- content increased obviously under saline stress but had little change under alkaline stress. The increments of proline and organic acid were both greater under alkaline stress, but organic acid content kept the same level under saline stress. Alkaline stress caused more harmful effects on growth and physiological changes in oat seedlings especially broke the pH stability in the root tissue fluid. Physiological adaptive mechanisms of oat seedlings under saline stress and alkaline stress were different, which mainly took the way of accumulating organic acid under alkali stress but accumulating Cl- under saline stress
Effects of Chinese Medicine Tong xinluo on Diabetic Nephropathy via Inhibiting TGF- β
Diabetic nephropathy (DN) is a major cause of chronic kidney failure and characterized by interstitial and glomeruli fibrosis. Epithelial-to-mesenchymal transition (EMT) plays an important role in the pathogenesis of DN. Tong xinluo (TXL), a Chinese herbal compound, has been used in China with established therapeutic efficacy in patients with DN. To investigate the molecular mechanism of TXL improving DN, KK-Ay mice were selected as models for the evaluation of pathogenesis and treatment in DN. In vitro, TGF-β1 was used to induce EMT. Western blot (WB), immunofluorescence staining, and real-time polymerase chain reaction (RT-PCR) were applied to detect the changes of EMT markers in vivo and in vitro, respectively. Results showed the expressions of TGF-β1 and its downstream proteins smad3/p-smad3 were greatly reduced in TXL group; meantime, TXL restored the expression of smad7. As a result, the expressions of collagen IV (Col IV) and fibronectin (FN) were significantly decreased in TXL group. In vivo, 24 h-UAER (24-hour urine albumin excretion ratio) and BUN (blood urea nitrogen) were decreased and Ccr (creatinine clearance ratio) was increased in TXL group compared with DN group. In summary, the present study demonstrates that TXL successfully inhibits TGF-β1-induced epithelial-to-mesenchymal transition in DN, which may account for the therapeutic efficacy in TXL-mediated renoprotection
Meteorin-like/Metrnl, a novel secreted protein implicated in inflammation, immunology, and metabolism: A comprehensive review of preclinical and clinical studies
Meteorin-like, also known as Metrnl, Meteorin-β, Subfatin, and Cometin, is a novel secreted protein exerting pleiotropic effects on inflammation, immunology, and metabolism. Earlier research on this hormone focused on regulating energy expenditure and glucose homeostasis. Consequently, several studies attempted to characterize the molecule mechanism of Metrnl in glucose metabolism and obesity-related disorders but reported contradictory clinical results. Recent studies gradually noticed its multiple protective functions in inflammatory immune regulations and cardiometabolic diseases, such as inducing macrophage activation, angiogenesis, tissue remodeling, bone formation, and preventing dyslipidemias. A comprehensive understanding of this novel protein is essential to identify its significance as a potential therapeutic drug or a biomarker of certain diseases. In this review, we present the current knowledge on the physiology of Metrnl and its roles in inflammation, immunology, and metabolism, including animal/cell interventional preclinical studies and human clinical studies. We also describe controversies regarding the data of circulation Metrnl in different disease states to determine its clinical application better
Plant biomass allocation and driving factors of grassland revegetation in a Qinghai-Tibetan Plateau chronosequence
Biomass allocation is a key factor in understanding how ecosystems respond to changing environmental conditions. The role of soil chemistry in the above- and belowground plant biomass allocation in restoring grassland is still incompletely characterized. Consequently, it has led to two competing hypotheses for biomass allocation: optimal partitioning, where the plants allocate biomass preferentially to optimize resource use; and the isometric hypothesis, which postulates that biomass allocation between roots and shoots is fixed. Here we tested these hypotheses over a chronosequence of alpine grasslandsion undergoing restoration in the Qinghai-Tibetan Plateau, these range from severely degraded to those with 18 years of revegetation with an intact grassland (as a reference). A high proportion of biomass was allocated to the roots in the revegetated grasslands, and more biomass to shoots in the degraded and intact grasslands. The grasslands gradually decreased their root to shoot ratio as revegetation continued, with the lowest value in year 18 of revegetation. Our results showed that aboveground biomass (AGB) was increased by available phosphorus (P), soil moisture, and negatively related to bulk density, while belowground biomass (BGB) was positively impacted by total P and negatively by nitrate nitrogen (N). The trade-off between them was positively associated with available P and nitrate-N, and soil nutrient availability is more linked to increased AGB relative to BGB. Our study indicates that biomass allocation is highly variable during the revegetation period from degraded grassland, and is linked with soil properties, thus supporting the optimal partitioning hypothesis.</p
Effect of Tongxinluo on Nephrin Expression via Inhibition of Notch1/Snail Pathway in Diabetic Rats
Spin pinning effect to reconstructed oxyhydroxide layer on ferromagnetic oxides for enhanced water oxidation.
Producing hydrogen by water electrolysis suffers from the kinetic barriers in the oxygen evolution reaction (OER) that limits the overall efficiency. With spin-dependent kinetics in OER, to manipulate the spin ordering of ferromagnetic OER catalysts (e.g., by magnetization) can reduce the kinetic barrier. However, most active OER catalysts are not ferromagnetic, which makes the spin manipulation challenging. In this work, we report a strategy with spin pinning effect to make the spins in paramagnetic oxyhydroxides more aligned for higher intrinsic OER activity. The spin pinning effect is established in oxideFM/oxyhydroxide interface which is realized by a controlled surface reconstruction of ferromagnetic oxides. Under spin pinning, simple magnetization further increases the spin alignment and thus the OER activity, which validates the spin effect in rate-limiting OER step. The spin polarization in OER highly relies on oxyl radicals (O∙) created by 1st dehydrogenation to reduce the barrier for subsequent O-O coupling
Vomiting and wasting disease associated with hemagglutinating encephalomyelitis viruses infection in piglets in jilin, china
One coronavirus strain was isolated from brain tissues of ten piglets with evident clinical manifestations of vomiting, diarrhea and dyskinesia in Jilin province in China. Antigenic and genomic characterizations of the virus (isolate PHEV-JLsp09) were based on multiplex PCR and negative staining electron microscopy and sequence analysis of the Hemagglutinin-esterase (HE) gene. These piglets were diagnosed with Porcine hemagglutinating encephalomyelitis virus (PHEV)
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