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Huangtai algal blooms are key indicators of eutrophication and lake-ecosystem damage. Understanding the spatiotemporal heterogeneity of their growth is critical for preserving the ecological environment. The dimidiate pixel model is commonly used to estimate vegetation coverage; however, indices such as the normalized difference vegetation index have not been specifically constructed for the Huangtai algae spectrum and thus are not specific or sufficiently precise for use as indicators. Therefore, we propose a new dimidiate pixel model based on a novel additive vegetation index to calculate the Huangtai algal coverage for each pixel using Landsat multispectral satellite images with 30-m resolution. The results showed that the additive vegetation index with R

Shallow eutrophic lakes contribute disproportional to the emissions of CO

In this study, physical experiments, clay mineral determination, and pH testing were performed to examine the basic properties of soil samples from a soil material yard selected for dam construction at Hua’ao Lake, Qian’an County, Jilin Province, China. The results show that the soil in the study area is cohesive, the mineral content of illite in the illite/montmorillonite mixed layer is approximately 50%, and the pH value of the environment from which the soil samples were taken is 8.43-8.91. These factors enable the soil in this area to be dispersed. The dispersibility of the soil sampled from this area was evaluated by a double hydrometer test, a pinhole test, a fragmentation test, a sodium adsorption ratio test, and determination of the percentage of exchangeable sodium ions. Because these test methods had inconsistent results, the test methods in combination with the typical geomorphic conditions of the sampling points were ultimately used to comprehensively evaluate the soil dispersion. The results demonstrate that the cohesive soil sampled from the soil material yard is dispersible and must be treated with improvement measures before it can be used as a filling material for the dam. To improve the dispersive and transitional soil, 2%, 3%, 4%, 5%, and 6% L1Fa2 (a 1 : 2 ratio of lime and fly ash) and C1L1Fa4 (a 1 : 1 : 4 ratio of cement, lime, and fly ash) were used to perform improvement tests on 10 groups of dispersive soil samples and 10 groups of transitional soil samples. The results reveal that the addition of 4% L1Fa2 best improves the dispersive soil in this area. Therefore, the soil intended for this project should be used as a dam-building material after improvement with the 4% addition of L1Fa2.

Summary Emerging evidence indicates that the dysregulation of protein ubiquitination plays a crucial role in aging‐associated diseases. Smad‐dependent canonical BMP signaling pathway is indispensable for osteoblastic bone formation, which could be disrupted by the ubiquitination and subsequent proteasomal degradation of Smad1/5, the key molecules for BMP signaling transduction. However, whether the dysregulation of Smad1/5 ubiquitination and disrupted BMP signaling pathway is responsible for the age‐related bone formation reduction is still underexplored. Pleckstrin homology domain‐containing family O member 1 (PLEKHO1) is a previously identified ubiquitination‐related molecule that could specifically target the linker region between the WW domains of Smurf1 to promote the ubiquitination of Smad1/5. Here, we found an age‐related increase in the expression of PLEKHO1 in bone specimens from either fractured patients or aging rodents, which was associated with the age‐related reduction in Smad‐dependent BMP signaling and bone formation. By genetic approach, we demonstrated that loss of Plekho1 in osteoblasts could promote the Smad‐dependent BMP signaling and alleviated the age‐related bone formation reduction. In addition, osteoblast‐specific Smad1 overexpression had beneficial effect on bone formation during aging, which could be counteracted after overexpressing Plekho1 within osteoblasts. By pharmacological approach, we showed that osteoblast‐targeted Plekho1 siRNA treatment could enhance Smad‐dependent BMP signaling and promote bone formation in aging rodents. Taken together, it suggests that the increased PLEKHO1 could suppress Smad‐dependent BMP signaling to inhibit bone formation during aging, indicating the translational potential of targeting PLEKHO1 in osteoblast as a novel bone anabolic strategy for reversing established osteoporosis during aging.

Background: This meta-analysis was conducted to compare the effects and safety of teriparatide with risedronate in the treatment of osteoporosis. Material and methods: PubMed, Embase, Web of Science and Cochrane library database were systematically reviewed for studies published up to February 24, 2019. Eligible studies that compared the effects of teriparatide with risedronate in osteoporosis were included in this meta-analysis. The outcomes included percentage change in bone mineral density (BMD) of lumbar spine, femoral neck, and total hip, the incidence of clinical fractures, serum bone markers, and adverse events. A random-effects or fixed-effects model was used to pool the estimate, according to the heterogeneity among the included studies. Results: Seven studies were included in this meta-analysis. Compared with risedronate, teriparatide was associated with a significant increase in lumbar spine BMD [weight mean difference (WMD)=4.24, 95%CI: 3.11, 5.36; P

Currently, major concerns about the safety and efficacy of RNA interference (RNAi)-based bone anabolic strategies still exist because of the lack of direct osteoblast-specific delivery systems for osteogenic siRNAs. Here we screened the aptamer CH6 by cell-SELEX, specifically targeting both rat and human osteoblasts, and then we developed CH6 aptamer-functionalized lipid nanoparticles (LNPs) encapsulating osteogenic pleckstrin homology domain-containing family O member 1 (Plekho1) siRNA (CH6-LNPs-siRNA). Our results showed that CH6 facilitated in vitro osteoblast-selective uptake of Plekho1 siRNA, mainly via macropinocytosis, and boosted in vivo osteoblast-specific Plekho1 gene silencing, which promoted bone formation, improved bone microarchitecture, increased bone mass and enhanced mechanical properties in both osteopenic and healthy rodents. These results indicate that osteoblast-specific aptamer-functionalized LNPs could act as a new RNAi-based bone anabolic strategy, advancing the targeted delivery selectivity of osteogenic siRNAs from the tissue level to the cellular level.

The thermal analysis-mass spectrometric coupling technique for traditional thermal analysis is a major breakthrough. It has been started its wide applications, not only for the inoganic and organic, but also for the organic-inorganic composite materials. Many scientists and technicians have paid their great attentions to the coupling techniques. The new progresses of the thermal analysis coupling with mass specstrometry are introduced in this paper.

The role of osteoclastic miRNAs in regulating osteolytic bone metastasis (OBM) of breast cancer is still underexplored. Here, we examined the expression profiles of osteoclastogenic miRNAs in human bone specimens and identified that miR-214-3p was significantly upregulated in breast cancer patients with OBM. Consistently, we found increased miR-214-3p within osteoclasts, which was associated with the elevated bone resorption, during the development of OBM in human breast cancer xenografted nude mice (BCX). Furthermore, genetic ablation of osteoclastic miR-214-3p in nude mice prevent the development of OBM. Conditioned medium from MDA-MB-231 cells dramatically stimulated miR-214-3p expression to promote osteoclast differentiation. Mechanistically, a series of in vitro study showed that miR-214-3p directly targeted Traf3 to promote osteoclast activity and bone-resorbing activity. In addition, osteoclast-specific miR-214-3p knock-in mice showed remarkably increased bone resorption when compared to the littermate controls, which was attenuated after osteoclast-targeted treatment with Traf3 3′UTR-containing plasmid. In BCX nude mice, osteoclast-targeted antagomir-214-3p delivery could recover the TRAF3 protein expression and attenuate the development of OBM, respectively. Collectively, inhibition of osteoclastic miR-214-3p may be a potential therapeutic strategy for breast cancer patients with OBM. Meanwhile, the intraosseous TRAF3 could be a promising biomarker for evaluation of the treatment response of antagomir-214-3p.

Emerging evidence indicates that osteoclasts direct osteoblastic bone formation. MicroRNAs (miRNAs) have a crucial role in regulating osteoclast and osteoblast function. However, whether miRNAs mediate osteoclast-directed osteoblastic bone formation is mostly unknown. Here, we show that increased osteoclastic miR-214-3p associates with both elevated serum exosomal miR-214-3p and reduced bone formation in elderly women with fractures and in ovariectomized (OVX) mice. Osteoclast-specific miR-214-3p knock-in mice have elevated serum exosomal miR-214-3p and reduced bone formation that is rescued by osteoclast-targeted antagomir-214-3p treatment. We further demonstrate that osteoclast-derived exosomal miR-214-3p is transferred to osteoblasts to inhibit osteoblast activity in vitro and reduce bone formation in vivo. Moreover, osteoclast-targeted miR-214-3p inhibition promotes bone formation in ageing OVX mice. Collectively, our results suggest that osteoclast-derived exosomal miR-214-3p transfers to osteoblasts to inhibit bone formation. Inhibition of miR-214-3p in osteoclasts may be a strategy for treating skeletal disorders involving a reduction in bone formation., In previous studies the authors discovered that miR-214 inhibits osteoblastic bone formation. Here they extend on these findings, using ovariectomized mice and samples from patients with bone fractures, to show that miR-214 is a mediator of osteoclast-osteoblast crosstalk.

To develop a new alloy with high hydrogen storage capacity, partial Cr in TiCr1.8 was substituted by V–Fe alloy. X-ray diffraction and metallography observation proved that the substitution did not change the phase constitution of TiCr1.2(V–F)0.6. It still remained in its initial Laves phase related body centred cubic structure. Pressure–composition–temperature tests showed that the hydrogen storage capacity could reach up to 3.2 wt% and its reversible capacity to about 2.0 wt%. TG-DSC tests showed that there are two kinds of tetrahedral site for hydrogen atoms to locate.

The variations of water level in reservoir have significant to the stability of the reservoir slope. Analyzing the influence factors which fluctuation of water table for slope by the Finite Element Method and Limit Equilibrium Method. Analyzing the stress field, strain field and stability for Jiu-zi collapse deposit in different reservoir water level, and getting the results that the distribution characteristics stress and strain in different water level. Using FEM based on shear strength reduction methods and Limit Equilibrium Method, results show: (1) The numerical value of horizontal displacement and shear stress is the largest in the low water level, as the water level rises, the value become decrease. (2) As the water level rises, stability coefficient increases, therefore, it is less likely to cause deep slip. (3) The former have a larger numerical value than the latter with the FEM based on shear strength reduction methods and Limit Equilibrium Method.

Lake Wuliangsuhai is one of the representative inland freshwater lakes in grassland areas of China, and its shrinking and eutrophication is becoming more serious. The study on the ecological and environmental effects of the shrinking and eutrophication revealed that the total nitrogen (TN) content in the surface sediment of the lake had an obvious differentiation both in longitudinal and in latitudinal direction, and had a significant correlation with organic matter content. The mean C/N ratio of the sediment ranged from 12.07 to 19.95, which meant that the organic matter was mainly come from the hydrophytes of the lake, and the eutrophication of the lake was mostly caused by its internal load. Both TN and organic matter had a clear grain-size effect in different fractions of grain sizes of surface sediment, and their contents in IV (63 microm) were as 3.1 - 7.6 and 2.5 - 8.0 times as those in I (250 microm), respectively.