p38α MAPK regulates proliferation and differentiation of osteoclast progenitors and bone remodeling in an aging-dependent manner.

Bone mass is determined by the balance between bone formation, carried out by mesenchymal stem cell-derived osteoblasts, and bone resorption, carried out by monocyte-derived osteoclasts. Here we investigated the potential roles of p38 MAPKs, which are activated by growth factors and cytokines including RANKL and BMPs, in osteoclastogenesis and bone resorption by ablating p38α MAPK in LysM+monocytes. p38α deficiency promoted monocyte proliferation but regulated monocyte osteoclastic differentiation in a cell-density dependent manner, with proliferating p38α-/- cultures showing increased differentiation. While young mutant mice showed minor increase in bone mass, 6-month-old mutant mice developed osteoporosis, associated with an increase in osteoclastogenesis and bone resorption and an increase in the pool of monocytes. Moreover, monocyte-specific p38α ablation resulted in a decrease in bone formation and the number of bone marrow mesenchymal stem/stromal cells, likely due to decreased expression of PDGF-AA and BMP2. The expression of PDGF-AA and BMP2 was positively regulated by the p38 MAPK-Creb axis in osteoclasts, with the promoters of PDGF-AA and BMP2 having Creb binding sites. These findings uncovered the molecular mechanisms by which p38α MAPK regulates osteoclastogenesis and coordinates osteoclastogenesis and osteoblastogenesis

A Compact Convolutional Neural Network for Surface Defect Inspection

The advent of convolutional neural networks (CNNs) has accelerated the progress of computer vision from many aspects. However, the majority of the existing CNNs heavily rely on expensive GPUs (graphics processing units). to support large computations. Therefore, CNNs have not been widely used to inspect surface defects in the manufacturing field yet. In this paper, we develop a compact CNN-based model that not only achieves high performance on tiny defect inspection but can be run on low-frequency CPUs (central processing units). Our model consists of a light-weight (LW) bottleneck and a decoder. By a pyramid of lightweight kernels, the LW bottleneck provides rich features with less computational cost. The decoder is also built in a lightweight way, which consists of an atrous spatial pyramid pooling (ASPP) and depthwise separable convolution layers. These lightweight designs reduce the redundant weights and computation greatly. We train our models on groups of surface datasets. The model can successfully classify/segment surface defects with an Intel i3-4010U CPU within 30 ms. Our model obtains similar accuracy with MobileNetV2 while only has less than its 1/3 FLOPs (floating-point operations per second) and 1/8 weights. Our experiments indicate CNNs can be compact and hardware-friendly for future applications in the automated surface inspection (ASI)

A two-photon fluorogenic probe based on a coumarin schiff base for formaldehyde detection in living cells

A novel two-photon fluorogenic probe has been developed to detect formaldehyde with fast response, low cytotoxicity, and excellent selectivity. This probe exhibits a strong turn-on fluorescence response to formaldehyde under excitation at 370 nm and has been successfully applied to detect formaldehyde in living cells. Theoretical calculations at the B3LYP/6-31 + G(d,p), APFD/6-311++G, and APFD/6-311 + G(2d,p) levels of theory for the absorption and emission wavelengths of the probes were in agreement with those obtained experimentally

Safety evaluation of transgenic potatoes transformed with synthetic antibacterial peptide gene - toxicological test

Cecropin B is an antibacterial peptide commonly existing in the insect immune system. During the past decade, we have designed and synthesized various novel antibacterial peptides and corresponding genes, such as modified Cecropin B, Shiva A and Shiva 2A (an analog of Cecropin B with 40% of amino acid sequence homology) and WHD. 3 clones with significant enhanced resistance to bacterial wilt (caused by Pseudomonas solanacearum) have been obtained. As part of the biosafety assessment of the transgenic potato, here we report the results of toxicological tests obtained using the synthetic peptide Shiva 2A. The acute toxicity study used the Ames, micronucleus and chromosome aberration tests together with accumulative toxicity to mice

Directly Controlling the Transport Properties of All-Nitride Josephson Junctions by N-Vacancy Defects

All-nitride Josephson junctions are being actively explored for applications in superconducting quantum chips because of their unique advantages including their antioxidant chemical stability and high crystal quality. However, the theoretical research on their microstructure mechanism that determines transport properties is still absent, especially on the defects. In this paper, we apply the first principles and non-equilibrium Green’s function to calculate the electrical transport characteristics of the yellow preset model. It is first revealed that the N-vacancy defects play a crucial role in determining the conductivity of the NbN-based Josephson junctions, and demonstrate the importance for the uniformity of vacancy distribution. It is found that the uniform number of vacancies can effectively increase the conductance of Josephson junction, but the position distribution of vacancies has little effect on the conductance. The work clarifies the effect of the N-vacancy defects on the conductivity of the NbN-based Josephson junctions, which offers useful guidance for understanding the microscope mechanism of the NbN-based Josephson junction, thus showing a great prospect in the improvement of the yield of superconducting quantum chips in the future

Evaluation of Various Scintillator Materials in Radiation Detector Design for Positron Emission Tomography (PET)

The performance of radiation detectors used in positron-emission tomography (PET) is determined by the intrinsic properties of the scintillators, the geometry and surface treatment of the scintillator crystals and the electrical and optical characteristics of the photosensors. Experimental studies were performed to assess the timing resolution and energy resolution of detectors constructed with samples of different scintillator materials (LaBr3, CeBr3, LFS, LSO, LYSO: Ce, Ca and GAGG) that were fabricated into different shapes with various surface treatments. The saturation correction of SiPMs was applied for tested detectors based on a Tracepro simulation. Overall, we tested 28 pairs of different forms of scintillators to determine the one with the best CTR and light output. Two common high-performance silicon photomultipliers (SiPMs) provided by SensL (J-series, 6 mm) or AdvanSiD (NUV, 6 mm) were used for photodetectors. The PET detector constructed with 6 mm CeBr3 cubes achieved the best CTR with a FWHM of 74 ps. The 4 mm co-doped LYSO: Ce, Ca pyramid crystals achieved 88.1 ps FWHM CTR. The 2 mm, 4 mm and 6 mm 0.2% Ce, 0.1% Ca co-doped LYSO cubes achieved 95.6 ps, 106 ps and 129 ps FWHM CTR, respectively. The scintillator crystals with unpolished surfaces had better timing than those with polished surfaces. The timing resolution was also improved by using certain geometric factors, such as a pyramid shape, to improve light transportation in the scintillator crystals

Heterologous Biosynthesis of Hyaluronic Acid Using a New Hyaluronic Acid Synthase Derived from the Probiotic <i>Streptococcus thermophilus</i>

Hyaluronic acid (HA) is a natural linear polysaccharide extensively used in many fields, including the food, medicine, and cosmetics industries. Currently, species that produce HA synthetase (HAS) from microbial sources are relatively small and mainly pathogenic, such as Streptococcus pyogenes and Pasteurella multicide. Moreover, there is limited research on the safe microbial sources of HAS. Thus, we characterized SthasA, a HAS derived from the probiotic Streptococcus thermophilus, and used it for the de novo synthesis of HA in a chassis strain of Bacillus amyloliquefaciens. Metabolic engineering of the precursor supply modules suggested that hasB (encoding UDPG dehydrogenase), which was derived from Corynebacterium glutamicum ATCC 13032, effectively promoted the accumulation of HA products. Furthermore, by combining the expression of the global regulatory factor CcpA, HA yield from the recombinant strain reached 3.20 g/L. Finally, we obtained a yield of 5.57 g/L HA with a molecular weight of 1.7 × 106 Da using various process optimization strategies in a 5 L bioreactor. This study enriches our understanding of obtaining HAS from non-pathogenic bacteria and provides a safe and effective process for producing HA, which has the potential to promote the industrial applications of HA further