Software Optimization in Ultrasound Imaging Technique Using Improved Deep Belief Learning Network on the Internet of Medical Things Platform

Wireless Personal Communications - The Internet of Medical Things (IoMT) is the array of medical instruments and related technologies that link Information Technology (IT) systems in...     

宜昌晒旗河磷矿条带充填法采场结构及回采顺序研究

复杂地形条件下矿体安全高效开采研究对于释放矿山资源产能有着重要意义。为解决目前房柱法开采对地表扰动程度大且矿柱难以回收等问题，基于条带充填开采技术，从采场结构及回采顺序两个方面对宜昌晒旗河磷矿展开了适应性研究，以期在提高矿石回收率的同时减少地表扰动。首先依据晒旗河高山河谷地形下地应力特征，在盘区内划分了高低应力采区，构建了分区采场结构，并引入极限强度理论得到条带矿柱的合理宽度；然后设计了高应力采区“隔一”、低应力采区“隔一采一”的条带回采顺序，运用FLAC3D数值软件优选出高、低应力采区间的回采顺序，研究矿体在开挖过程中围岩应力变化特征及地表变形特征。结果表明：①从低应力采区向高应力采区的回采顺序优势明显，可缓解高低应力采区的应力不均匀程度；②在整个回采及充填过程中，采场围岩较稳定，矿柱所受的垂直压应力均小于抗压强度；③高山河谷地形下地表沉降曲线演化特征为“U→V→U→W”，地表沉降得到了有效控制；④所设计的条带充填法与传统房柱法开采相比，矿石开采效率得到了大幅提升，可为晒旗河磷矿及类似高山河谷地形下矿床开采提供技术指导。     

Molecular dynamics investigations on the interfacial energy and adhesive strength between C60-filled carbon nanotubes and metallic surface

The mechanical and adhesive properties of C₆₀@(10,10) carbon nanopeapods (CNPs) adhering to gold surfaces are investigated by atomistic simulations. The effects of C₆₀ fill density, tube length, surrounding temperature, and peeling velocity on the adhesion behavior are studied. Results show that the interfacial binding energy of CNPs (which depends on the C₆₀ fill density and temperature) is 2.0∼4.4% higher than that of (10,10) single-walled CNTs and 3.4∼4.7% lower than that of (5,5)@(10,10) double-walled CNTs (DWCNTs). Despite their lower interfacial binding energy, CNPs have a higher adhesive strength than that of DWCNTs (1.53 nN vs. 1.4 nN). Distinct from the inner tubes of DWCNTs, which have continuum mechanical properties, the discrete C₆₀ molecules that fill CNPs exhibit unique composite mechanical properties, with high flexibility and bend-buckling resistance. The bend-buckling forces for CNPs filled with a low/medium fill density of C₆₀ are approximately constant. When the fill density is 1 C₆₀ molecule per nanometer length, the bend-buckling force dramatically increases.     

Coupled nanowire-based hybrid plasmonic nanocavities on thin substrates

We theoretically analyze nanowire-based hybrid plasmonic nanocavities on thin substrates at visible wavelengths. In the presence of thin suspended substrates, the hybrid plasmonic modes, formed by the coupling between a metal nanowire and a dielectric nanowire with optical gain, exhibit negligible substrate-mediated characteristics and overlap better with the gain region. Consequently, the confinement factor of the guided hybrid modes is enhanced by more than 42%. However, the presence of significant mirror loss remains the main challenge to lasing. By adding silver coatings with a sufficient thickness range on the two end facets, we show that the reflectivity is substantially enhanced to above 50%. For a coating thickness of 50 nm and cavity length of about 4 μm, the quality factor is above 100.     

不锈钢钣金件替代木质家具的应用研究

提出以不锈钢钣金件为材料,依靠专业造型软件进行工艺设计,经过一定的机械加工成型方法,表面进行喷涂工艺处理,制造成各种为家庭所需要的用具;来替代木质家具.该应用研究将有利于环境保护.     

Hydroxyapatite extracted from fish scale: Effects on MG63 osteoblast-like cells

In recent years, environmental and economic conditions have raised concerns about the treatment and use of bio-waste. This study analyzed hydroxyapatite extracted from fish scale (FHAP) by enzymatic hydrolysis. The structures of FHAP were characterized by Fourier transform infrared spectroscopy, particle size analyzer, scanning electron microscopy, X-ray diffraction, and energy dispersive spectrometry. The analytical results indicated that FHAP consisted of nano-sized particles with Ca/P ratio of 1.76. After FHAP particles were sintered at 800°C for 4 h, the particles showed increased porosity and surface roughness. The influence of FHAP particles on the proliferation and osteogenic differentiation of MG63 cells was also investigated. Compared with hydroxyapatite from Sigma (SHAP), FHAP significantly increased MG63 growth, whether hydroxyapatite powders were sintered or not. Under osteogenic-inductive culture condition, FHAP particles promoted osteogenic differentiation and mineralization of MG63 cells, which was confirmed by alkaline phosphate assay and von Kossa staining. This study confirms that FHAP extracted by enzymatic hydrolysis is a promising biomaterial for artificial bone fabrication.     

Targeting Intra-Pulmonary P53-Dependent Long Non-Coding RNA Expression as a Therapeutic Intervention for Systemic Lupus Erythematosus-Associated Diffuse Alveolar Hemorrhage

Diffuse alveolar hemorrhage (DAH) in systemic lupus erythematosus (SLE) is associated with significant mortality, requiring a thorough understanding of its complex mechanisms to develop novel therapeutics for disease control. Activated p53-dependent apoptosis with dysregulated long non-coding RNA (lncRNA) expression is involved in the SLE pathogenesis and correlated with clinical activity. We examined the expression of apoptosis-related p53-dependent lncRNA, including H19, HOTAIR and lincRNA-p21 in SLE-associated DAH patients. Increased lincRNA-p21 levels were detected in circulating mononuclear cells, mainly in CD4+ and CD14+ cells. Higher expression of p53, lincRNA-p21 and cell apoptosis was identified in lung tissues. Lentivirus-based short hairpin RNA (shRNA)-transduced stable transfectants were created for examining the targeting efficacy in lncRNA. Under pristane stimulation, alveolar epithelial cells had increased p53, lincRNA-p21 and downstream Bax levels with elevated apoptotic ratios. After pristane injection, C57/BL6 mice developed DAH with increased pulmonary expression of p53, lincRNA-p21 and cell apoptosis. Intra-pulmonary delivery of shRNA targeting lincRNA-p21 reduced hemorrhage frequencies and improved anemia status through decreasing Bax expression and cell apoptosis. Our findings demonstrate increased p53-dependent lncRNA expression with accelerated cell apoptosis in the lungs of SLE-associated DAH patients, and show the therapeutic potential of targeting intra-pulmonary lncRNA expression in a pristane-induced model of DAH.     

Synthesis of Pb(Ni1/3Nb2/3)0.72Ti0.28O3 perovskite ceramics by a reaction-sintering process

Pb(Ni_1/3Nb_2/3)_0.72Ti_0.28O₃ (PNNT) perovskite ceramics produced by a reaction-sintering process were investigated. Without any calcination, the mixture of PbO, Ni(NO₃)₂, Nb₂O₅ and TiO₂ was pressed and sintered directly into PNNT ceramics. PNNT ceramics of 100% perovskite phase were obtained. For PNNT sintered for 2 h in PbO compensated atmosphere, maximum density reaches a value 8.49 g/cm³ (99.8% of the theoretical value) at 1250^∘C. A maximum dielectric constant 20600 occurred around 37^∘C at 1 kHz in PNNT sintered at 1250^∘C for 2 h.     

Electromagnetic scattering model for a tree trunk above a tiltedground plane

An efficient and realistic electromagnetic scattering model for a tree trunk above a ground plane is presented. The trunk is modeled as a finite-length stratified dielectric cylinder with a corrugated bark layer. The ground is considered to be a smooth homogeneous dielectric with an arbitrary slope. The bistatic scattering response of the cylinder is obtained by invoking two approximations. In the microwave region, the height of the tree trunks are usually much larger than the wavelength. Therefore the interior fields in a finite length cylinder representing a tree trunk can be approximated with those of an infinite cylinder with the same physical and electrical radial characteristics. Also an approximate image theory is used to account for the presence of the dielectric ground plane which simply introduces an image excitation wave and an image scattered field. An asymptotic solution based on the physical optics approximation is derived which provides a fast algorithm with excellent accuracy when the radii of the tree trunks are large compared to the wavelength. The effect of a bark layer is also taken into account by simply replacing the bark layer with an anisotropic layer. It is shown that the corrugated layer acts as an impedance transformer which may significantly decrease the backscattering radar cross section depending on the corrugation parameters. It is also shown that for a tilted ground plane a significant cross-polarized backscattered signal is generated while the co-polarized backscattered signal is reduced     

An efficient non-dominated sorting method for evolutionary algorithms

We present a new non-dominated sorting algorithm to generate the non-dominated fronts in multi-objective optimization with evolutionary algorithms, particularly the NSGA-II. The non-dominated sorting algorithm used by NSGA-II has a time complexity of O(MN(2)) in generating non-dominated fronts in one generation (iteration) for a population size N and M objective functions. Since generating non-dominated fronts takes the majority of total computational time (excluding the cost of fitness evaluations) of NSGA-II, making this algorithm faster will significantly improve the overall efficiency of NSGA-II and other genetic algorithms using non-dominated sorting. The new non-dominated sorting algorithm proposed in this study reduces the number of redundant comparisons existing in the algorithm of NSGA-II by recording the dominance information among solutions from their first comparisons. By utilizing a new data structure called the dominance tree and the divide-and-conquer mechanism, the new algorithm is faster than NSGA-II for different numbers of objective functions. Although the number of solution comparisons by the proposed algorithm is close to that of NSGA-II when the number of objectives becomes large, the total computational time shows that the proposed algorithm still has better efficiency because of the adoption of the dominance tree structure and the divide-and-conquer mechanism.