Preliminary study of regulation technology of wind field distribution on QTT site based on test of equivalent wind field

The effect of wind gust on the large reflector antenna is one of the main factors that can affect the antenna performance and therefore, this effect must be minimized to meet the strict performance requirement in the world largest steerable telescope, which is QiTai Telescope (QTT). In this paper, the characteristics of the topography as well as the wind distribution around QTT site have been analyzed and consequently, a technology for improving the wind distribution in an active way has been proposed. Additionally, an equivalent wind distribution test rig for the proposed technology has been built in the lab and the corresponding experiment has been carried out. The experimental data indicated that the proposed technology was a promising tool for regulating the wind distribution for the large reflector antenna and it was found that the proposed technology can significantly reduce the wind speed as well as the wind impact range after the wind regulation has been given in the test. The results in this paper has provided a solid foundation for the regulation of the wind distribution of the QTT site

Aspect of Clusters Correlation at Light Nuclei Excited State

The correlation of $\alpha\alpha$ was probed via measuring the transverse momentum $p_{T}$ and width $\delta p_{T}$ of one $\alpha$, for the first time, which represents the spatial and dynamical essentialities of the initial coupling state in $^{8}$Be nucleus. The weighted interaction vertex of 3$\alpha$ reflected by the magnitudes of their relative momentums and relative emission angles proves the isosceles triangle configuration for 3$\alpha$ at the high excited energy analogous Hoyle states.Comment: 8 pages, 9 figure

Variation of Tensor Force due to Nuclear Medium Effect

The enhancement of $J^{\pi}(T)$=3$^{+}$(0) state with isospin $T=0$ excited by the tensor force in the free $^{6}$Li nucleus has been observed, for the first time, relative to a shrinkable excitation in the $^{6}$Li cluster component inside its host nucleus. Comparatively, the excitation of $J^{\pi}(T)$=0$^{+}$(1) state with isospin $T=1$ for these two $^{6}$Li formations take on an approximately equal excitation strength. The mechanism of such tensor force effect was proposed due to the intensive nuclear medium role on isospin $T$=0 state.Comment: 6 pages, 4 figure

Multi-alpha Boson Gas state in Fusion Evaporation Reaction and Three-body Force

The experimental evidence for the $\alpha$ Boson gas state in the $^{11}$C+$^{12}$C$\rightarrow$$^{23}$Mg$^{\ast}$ fusion evaporation reaction is presented. By measuring the $\alpha$ emission spectrum with multiplicity 2 and 3, we provide insight into the existence of a three-body force among $\alpha$ particles. The observed spectrum exhibited distinct tails corresponding to $\alpha$ particles emitted in pairs and triplets consistent well with the model-calculations of AV18-UX and chiral effective field theory of NV2-3-la*, indicating the formation of $\alpha$ clusters with three-body force in the Boson gas state.Comment: 7 pages, 6 figure

LncRNA FGD5-AS1 promotes osteogenic differentiation of human bone marrow mesenchymal stem cells by regulating miR-93-5p/BMP2 axis

Objective To investigate the impact of long non-coding RNA (lncRNA) FGD5-AS1 on the osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBM-MSCs) through regulation of the microRNA miR-93-5p/bone morphogenetic protein-2(BMP2) axis. Methods hBM-MSCs in logarithmic growth phase were taken, and the expression levels of lncRNA FGD5-AS1, miR-93-5p and BMP2 mRNA were detected before and after osteogenic differentiation; The cells were transfected or co-transfected with pcDNA FGD5-AS1, miR-93-5p inhibitor, miR-93-5p mimics and corresponding negative controls, respectively, then divided into pcDNA NC group, pcDNA FGD5-AS1 group, inhibitor NC group, miR-93-5p inhibitor group, pcDNA FGD5-AS1+mimics NC group, or pcDNA FGD5-AS1+miR-93-5p mimics group and non-transfected cells were taken as blank group. CCK-8 assay was applied to detect cell proliferation ability of each group; Alkaline phosphatase (ALP) kit was applied to detect its activity; Alizarin red staining was applied to identify cellular mineralized nodule formation; Western blot was applied to detect the levels of BMP2, osteogenesis-related markers-osteocalcin (OCN), osteopontin (OPN), and osterix(OSX); Dual-luciferase experiment was applied to verify the targeting relationship of miR-93-5p with FGD5-AS1 and BMP2, respectively. Results lncRNA FGD5-AS1 and BMP2 were found to be targets of miR-93-5p. After osteogenic differentiation, the expression of FGD5-AS1 and BMP2 was increased and the expression of miR-93-5p was decreased (P＜0.05). Compared with pcDNA NC group, the expression of FGD5-AS1 in pcDNA FGD5-AS1 group was significantly increased(P＜0.05), indicating successful transfection; Mineralized nodules, cell proliferation, ALP activity and the expression of BMP2, OCN, OPN and OSX were obviously higher (P＜0.05) in pcDNA FGD5-AS1 group. Compared with the inhibitor NC group, the expression of miR-93-5p in miR-93-5p inhibitor group was significantly decreased (P＜0.05), indicating successful transfection; Mineralized nodules, cell proliferation, ALP activity and the expression of BMP2, OCN, OPN and OSX were obviously improved (P＜0.05) in miR-93-5p inhibitor group. Over-expression of miR-93-5p inhibited the promoting effect of FGD5-AS1 on the osteogenic differentiation of hBM-MSCs(P＜0.05). Conclusions Up-regulation of FGD-AS1 promotes the osteogenic differentiation of hBM-MSCs, which might be related to the miR-93-5p/BMP2 axis

Active Surface Compensation for Large Radio Telescope Antennas

With the development of radio telescope antennas with large apertures, high gain, and wide frequency bands, compensation methods, such as mechanical or electronic compensation, are obviously essential to ensure the electrical performance of antennas that work in complex environments. Since traditional compensation methods can only adjust antenna pointing but not the surface accuracy, which are limited for obtaining high surface precision and aperture efficiency, active surface adjustment has become an indispensable tool in this field. Therefore, the development process of electrical performance compensation methods for radio telescope antennas is introduced. Further, a series of analyses of the five key technologies of active surface adjustment is presented. Then, four typical large antennas that have been designed with active main reflector technology are presented and compared. Finally, future research directions and suggestions for reflector antenna compensation methods based on active surface adjustment are presented

Cerebral Microvascular Injury Induced by Lag3‐Dependent α‐Synuclein Fibril Endocytosis Exacerbates Cognitive Impairment in a Mouse Model of α‐Synucleinopathies

Abstract The pathological accumulation of α‐synuclein (α‐Syn) and the transmission of misfolded α‐Syn underlie α‐synucleinopathies. Increased plasma α‐Syn levels are associated with cognitive impairment in Parkinson's disease, multiple system atrophy, and dementia with Lewy bodies, but it is still unknown whether the cognitive deficits in α‐synucleinopathies have a common vascular pathological origin. Here, it is reported that combined injection of α‐Syn preformed fibrils (PFFs) in the unilateral substantia nigra pars compacta, hippocampus, and cerebral cortex results in impaired spatial learning and memory abilities at 6 months post‐injection and that this cognitive decline is related to cerebral microvascular injury. Moreover, insoluble α‐Syn inclusions are found to form in primary mouse brain microvascular endothelial cells (BMVECs) through lymphocyte‐activation gene 3 (Lag3)‐dependent α‐Syn PFFs endocytosis, causing poly(ADP‐ribose)‐driven cell death and reducing the expression of tight junction proteins in BMVECs. Knockout of Lag3 in vitro prevents α‐Syn PFFs from entering BMVECs, thereby reducing the abovementioned response induced by α‐Syn PFFs. Deletion of endothelial cell‐specific Lag3 in vivo reverses the negative effects of α‐Syn PFFs on cerebral microvessels and cognitive function. In short, this study reveals the effectiveness of targeting Lag3 to block the spread of α‐Syn fibrils to endothelial cells in order to improve cognition

Myo1d promotes alpha-synuclein transfer from brain microvascular endothelial cells to pericytes through tunneling nanotubes

Summary: α-Synuclein preformed fibrils (α-syn PFF) in the blood can cross the blood–brain barrier and invade the central nervous system. Our previous study proved that α-syn PFF can be taken up by brain microvascular endothelial cells (BMVECs). Here, we found that α-syn PFF spread from BMVECs to pericytes with the highest transmission efficiency. We observed abundant tunneling nanotubes (TNTs) connecting BMVECs and pericytes, and α-syn PFF transmitted through these TNTs. Furthermore, α-syn PFF accumulation in BMVECs did not promote TNT formation, but activated the molecular motor Myo1d. Inhibition of Myo1d prevented α-syn PFF transfer from BMVECs to pericytes and decreased the colocalization of Myo1d and F-actin in BMVECs. In summary, we are the first to demonstrate that α-syn PFF spread from BMVECs to pericytes through a mechanism involving TNTs and myosin. Targeting Myo1d may be a promising approach to prevent α-syn spreading from the blood to the brain