BMP4 inhibits myogenic differentiation of bone marrow–derived mesenchymal stromal cells in mdx mice

AbstractBackground aimsBone marrow–derived mesenchymal stromal cells (BMSCs) are a promising therapeutic option for treating Duchenne muscular dystrophy (DMD). Myogenic differentiation occurs in the skeletal muscle of the mdx mouse (a mouse model of DMD) after BMSC transplantation. The transcription factor bone morphogenic protein 4 (BMP4) plays a crucial role in growth regulation, differentiation and survival of many cell types, including BMSCs. We treated BMSCs with BMP4 or the BMP antagonist noggin to examine the effects of BMP signaling on the myogenic potential of BMSCs in mdx mice.MethodsWe added BMP4 or noggin to cultured BMSCs under myogenic differentiation conditions. We then injected BMP4- or noggin-treated BMSCs into the muscles of mdx mice to determine their myogenic potential.ResultsWe found that the expression levels of desmin and myosin heavy chain decreased after treating BMSCs with BMP4, whereas the expression levels of phosphorylated Smad, a downstream target of BMP4, were higher in these BMSCs than in the controls. Mdx mouse muscles injected with BMSCs pretreated with BMP4 showed decreased dystrophin expression and increased phosphorylated Smad levels compared with muscles injected with non-treated BMSCs. The opposite effects were seen after pretreatment with noggin, as expected.ConclusionsOur results identified BMP/Smad signaling as an essential negative regulator of promyogenic BMSC activity; inhibition of this pathway improved the efficiency of BMSC myogenic differentiation, which suggests that this pathway might serve as a target to regulate BMSC function for better myogenic differentiation during treatment of DMD and degenerative skeletal muscle diseases

Extremum characteristics of energy consumption in fluidization analyzed by using EMMS

This paper investigates the landscape of extremum characteristics for different energy consumption terms in gas-solid fluidization based on the Energy Minimization Multi-Scale (EMMS) model. The influence of typical cluster correlations on the extremum characteristics is also investigated to consolidate the results. The energy consumption terms are resolved into three types, i.e. suspension ("s"), transport ("t") of the particles and pure dissipation ("d") caused by their collisions and acceleration. Three regimes which are particle-dominated (PD), fluid-dominated (FD), and particle-fluid compromising (PFC) respectively subject to the extrema of epsilon = min, W-st = min and N-st = min, are investigated. Then the same procedure is extended to individual and combined terms (i.e. "s", "t", "d", "s+t", "t+d", "d+s") of energy consumption with respect to unit mass of particles ("N") and to unit volume of bed ("W"). The study of extremum characteristics reveals an enclosure structure which features an upper voidage regime corresponding to minimum energy dissipation rate (MinED), a lower voidage regime to maximum energy dissipation rate (MaxED) and a so-called mesoregime in between. The landscape of extremum characteristics reveals that the stability condition must be constructed according to clear physical meaning, otherwise misleading may occur due to multiple contradictive extrema exist in specific regimes. Although the clustering effects on extremum characteristics exposed some limitations of current correlations, the above-mentioned characteristics are found to be insensitive to cluster diameter correlations, indicating that the findings are intrinsic to the EMMS model. Further work is still needed to explore the mesoscale structure and its relationship with extremum behavior as well as underlying physics in fluidization

The Hyperbranched Polyester Reinforced Unsaturated Polyester Resin

We report a method of reinforcing and toughening unsaturated polyester resin (UPR) with a kind of hyperbranched polyester (HBP-1). Polyethylene glycol with different molecular weight was used as the core molecule of the preparation reaction, and the reaction product of phthalic anhydride and glycerol was used as the branching unit. The esterification reaction of polycondensation occurred, and then the hydroxyl-terminated hyperbranched polyester was prepared. The reaction product of maleic anhydride and isooctanol was added to the prepared hydroxyl-terminated hyperbranched polyester for esterification reaction. Both ends of the hyperbranched polyester had unsaturated double bond to obtain the hyperbranched polyester (HBP-1). The effects of this treatment on the morphology, mechanical properties and thermal properties of the composites were studied in detail. The HBP-1 was investigated by Fourier Transform Infrared Spectroscopy (FT-IR). The HBP-1/UPR composites were investigated by Thermogravimetric Analysis (TGA), Dynamic Mechanical Analysis (DMA), mechanical properties analysis and Scanning Electron Microscope (SEM). The results showed that HBP-1 enhanced the thermostability and mechanical properties of UPR. However, DMA indicated that the addition of HBP-1 cannot effectively improve the thermodynamic properties of UPR due to the flexible chain in HBP-1 structure. The HBP-1 improves tensile strength, bending strength and impact strength compared to neat UPR

Synthesis and properties of Alkyl <i>α-D-</i>Galactopyranoside

<p>Alkyl <i>α-D-</i>galactopyranosides are sugar-based nonionic surfactants, and it is necessary to research their structure–property relationships since it is not quite clear that the change of the alkyl chain length has effects on a series of physicochemical properties. Here, alkyl <i>α-D-</i>galactopyranosides were prepared by galactose and alcohols through three steps including acetylation, coupling with alcohols in the presence of a catalyst stannic chloride, and deprotection. Furthermore, their water solubility and other properties were investigated. Alkyl <i>α-D-</i>galactopyranosides (4a ∼ 4e, <i>n</i> = 6 ∼ 10) were water soluble, and their dissolution process in water was an endothermic process. Nonyl <i>α-D-</i>galactopyranoside (4d) showed excellent foaming ability and foam stability. Octyl <i>α-D-</i>galactopyranoside (4c) had the strongest emulsifying ability for toluene and nonyl <i>α-D-</i>galactopyranoside (4d) had the strongest emulsifying ability for rapeseed oil. The critical micelle concentration (CMC) values and surface tension at the CMC were decreasing with increasing alkyl chain length. Their standard free energy of adsorption (Δ<i>G</i>_ads) was more negative than their standard free energy of micellization (Δ<i>G</i>_mic). The moisture-absorption abilities were weakening with increasing alkyl chain length. Alkyl <i>α-D-</i>galactopyranosides (4a ∼4f) were thermally stable below 280°C. Alkyl <i>α-D-</i>galactopyranosides (4c ∼4f) had the optical texture of the thermotropic liquid crystal smectic A phase.</p

BO-DRNet: An Improved Deep Learning Model for Oil Spill Detection by Polarimetric Features from SAR Images

Oil spill pollution at sea causes significant damage to marine ecosystems. Quad-polarimetric Synthetic Aperture Radar (SAR) has become an essential technology since it can provide polarization features for marine oil spill detection. Using deep learning models based on polarimetric features, oil spill detection can be achieved. However, there is insufficient feature extraction due to model depth, small reception field lend due to loss of target information, and fixed hyperparameter for models. The effect of oil spill detection is still incomplete or misclassified. To solve the above problems, we propose an improved deep learning model named BO-DRNet. The model can obtain a more sufficiently and fuller feature by ResNet-18 as the backbone in encoder of DeepLabv3+, and Bayesian Optimization (BO) was used to optimize the model’s hyperparameters. Experiments were conducted based on ten prominent polarimetric features were extracted from three quad-polarimetric SAR images obtained by RADARSAT-2. Experimental results show that compared with other deep learning models, BO-DRNet performs best with a mean accuracy of 74.69% and a mean dice of 0.8551. This paper provides a valuable tool to manage upcoming disasters effectively

Identification of Substitutions and Small Insertion-Deletions Induced by Carbon-Ion Beam Irradiation in Arabidopsis thaliana

Heavy-ion beam irradiation is one of the principal methods used to create mutants in plants. Research on mutagenic effects and molecular mechanisms of radiation is an important subject that is multi-disciplinary. Here, we re-sequenced 11 mutagenesis progeny (M3) Arabidopsis thaliana lines derived from carbon-ion beam (CIB) irradiation, and subsequently focused on substitutions and small insertion-deletion (INDELs). We found that CIB induced more substitutions (320) than INDELs (124). Meanwhile, the single base INDELs were more prevalent than those in large size (≥2 bp). In details, the detected substitutions showed an obvious bias of C &gt; T transitions, by activating the formation of covalent linkages between neighboring pyrimidine residues in the DNA sequence. An A and T bias was observed among the single base INDELs, in which most of these were induced by replication slippage at either the homopolymer or polynucleotide repeat regions. The mutation rate of 200-Gy CIB irradiation was estimated as 3.37 × 10−7 per site. Different from previous researches which mainly focused on the phenotype, chromosome aberration, genetic polymorphism, or sequencing analysis of specific genes only, our study revealed genome-wide molecular profile and rate of mutations induced by CIB irradiation. We hope our data could provide valuable clues for explaining the potential mechanism of plant mutation breeding by CIB irradiation

Research Progress and Propect of Mustard Breeding

Mustard (Brassica juncea L.) is an important vegetable crop in China with a wide cultivation area and a long history of cultivation. With the increasing improvement of people's living standard and the changes in environmental conditions, new requirements for the quality and resistant varieties of mustard have been put forward. A large number of scientific researchers have completed the collection, conservation and gene function mining of a considerable amount of mustard germplasm resources, and have conducted researches on breeding and molecular biology, which has made great contributions to the improvement of mustard varieties. China is rich in mustard germplasm resources. There are many local varieties, and these local varieties are often faced with the problems of degradation of variety and quality defects after years of self-retaining, and how to improve these local varieties has become an urgent problem. This review describes the advanced breeding methods of mustard and their principles and the research results obtained. Advanced breeding methods mainly include mutagenesis breeding techniques, distant hybrid breeding techniques, transgenic breeding techniques, gene editing breeding techniques and molecular marker-assisted breeding techniques. The use of these advanced breeding techniques has not only made many achievements in changing the resistance, quality and adaptability of mustard varieties, but also helped to construct sterile lines to serve mustard cross breeding. In addition, this review also provides an outlook on the future research directions of mustard breeding in order to provide a theoretical basis and practical basis for the breeding of local special mustard varieties

Cloud Occlusion Probability Calculation Jointly Using Himawari-8 and CloudSat Satellite Data

Cloud occlusion is an important factor affecting flight safety and scientific observation. The calculation of Cloud Occlusion Probability (COP) is significant for the planning of the flight time and route of aircraft. Based on Himawari-8 and CloudSat satellite data, we propose a method to calculate the COP. The COP statistics were carried out on different distances in 12 directions 6 km above Beijing Capital International Airport (BCIA), at different heights and directions in the Haiyang aerostat production base, and at different times and seasons in Mount Qomolangma. It was found that the COP going in the southern direction from BCIA was greater than that in the northern direction by 0.67–3.12%, which is consistent with the climate conditions of Beijing. In Haiyang, the COP for several seasons in the direction of land was higher than in the direction of the ocean. The maximum COP for the 6 km altitude is 29.63% (summer) and the minimum COP is 7.59% (winter). The aerostat flight test can be conducted in the morning of winter and the direction of the ocean. The best scientific observation time for Mount Qomolangma is between 02:00 and 05:00 UTC in spring. With the increase in altitude, the COP gradually decreases. The research in this paper provides essential support for flight planning