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Zhong-Jun Chen, Xu-Sheng Zhao, Tie-Ping Fan, Heng-Xu Qi, Di Li Neurological Intervention Department, Dalian Municipal Central Hospital, Dalian, Liaoning Province, People’s Republic of ChinaCorrespondence: Di LiNeurological Intervention Department, Dalian Municipal Central Hospital, Dalian, Liaoning Province, People’s Republic of ChinaTel +86 411-84412001-8481Email xiangqing14740@163.comPurpose: To explore the molecular mechanism of glycine in improving ischemic stroke.Patients and Methods: The serum samples of patients with ischemic stroke and healthy people were compared. The ischemic stroke model of PC12 cells was established by oxygen-glucose deprivation (OGD). qPCR quantified miR-19a-3p and AMPK mRNA, and protein expression was detected by Western blot. MTT was used to detect cell activity. Flow cytometry was used to detect cells. Glucose metabolism kit was used to detect glucose intake and formation amount of lactic acid.Results: Compared with the control group, OGD group (OGDG) showed lower cell activity and increased cell apoptosis. TNF-α, IL-1βI, L-6, Caspase 3, Caspase 9 and Bax were up-regulated, and Glut1, HK2, LDHA, PDK1, PKM2 and Bcl2 were down-regulated. At the same time, glucose intake, formation amount of lactic acid and cell apoptosis rate were reduced, and AMPK/GSK-3β/HO-1 pathway activity was down-regulated. Glycine could counteract the above phenomena in OGDG. miR-19a-3p and AMPK decreased and increased, respectively, during glycine therapy. AMPK was the target gene of miR-19a-3p. Rescue experiments demonstrated that glycine improved cell apoptosis, inflammatory response and glucose metabolism disorder of ischemic stroke through miR-19a-3p/AMPK/GSK-3β/HO-1 pathway.Conclusion: Glycine improves ischemic stroke through miR-19a-3p/AMPK/GSK-3β/HO-1 pathway.Keywords: ischemic stroke, AMPK/GSK-3β/HO-1 pathway, miR-19a-3p, glycine

Cable capacity is one of the important parameters of cable engineering design and operation, and its value is obtained under the condition of constant load current. The load current of a power system usually varies periodically during actual operation. In order to study the transmission capacity of cable under periodic load, a numerical calculation program for transient temperature field of cable is compiled based on the finite difference method, and the temperature rise test of a direct buried cable is carried out with a large current. The results of the test are in agreement with the numerical results. This transient calculation program is used to calculate the temperature rise of the cable core under 24h periodic load and determine the periodic load carrying capacity, and an analytical calculation formula for calculating the periodic load carrying capacity of a direct buried cable is given.

By using small-angle x-ray scattering technique, correlation lengths of the density fluctuation are determined for the bulk metallic glass Zr41.2Ti13.8Cu12.5Ni10Be22.5 around the glass transition temperature Tg. Nanoscale inhomogeneities were found to exist in the supercooled liquid and glass state. The correlation length was found to vary with temperature T in an exponential law δ(T) = δ0+A1exp[−(T−T∞)/T1], where T∞ is the Vogel temperature, and parameters δ0, A1 and T1 were simulated to be 16.45 nm, 1.88×1029 nm, and 9.65 K, respectively, in the temperature region from Tg to Tg+80 K. The correlation length of the density fluctuation obtained by the small-angle x-ray scattering method can be considered as the characteristic length of glass transition.

Quantum spin liquid (QSL) is a novel state of matter with exotic excitations and was theoretically predicted to be realized most possibly in an S=1/2 kagome antiferromagnet. Experimentally searching for the candidate materials is a big challenge in condensed matter physics and only two such candidates were reported so far. Here we report the successful synthesis of a new spin-1/2 kagome antiferromagnet ZnCu3(OH)6SO4. No magnetic ordering is observed down to 50 mK, despite a moderately high Weiss temperature of {\theta}W ~ -79 K. It strongly suggests that the material is a new QSL candidate. Most interestingly, the magnetic specific heat clearly exhibits linear behaviors in two low-temperature regions. Both behaviors exactly correspond to two temperature-independent susceptibilities. These consistently reveal a novel re-entrance phenomenon of gapless QSL state at the lowest temperatures. The findings provide new insights into QSL ground and excited states and will inspire new theoretical and experimental studies., Comment: 27 pages, 5 figures

Cricket is a truculent insect with stiff and sharp teeth as a fighting weapon. The structure and possible biomineralization of the cricket teeth are always interested. Synchrotron radiation X-ray fluorescence, X-ray diffraction and small angle X-ray scattering techniques were used to probe the element distribution, possible crystalline structures and size distribution of scatterers in cricket teeth. Scanning electron microscope was used to observe the nanoscaled structure. The results demonstrate that Zn is the main heavy element in cricket teeth. The surface of the cricket teeth has a crystalline compound like ZnFe2(AsO4)2(OH)2(H2O)4. While, the interior of the teeth has a crystalline compound like ZnCl2, which is from the biomineralization. The ZnCl2-like biomineral forms nanoscaled microfibrils and their axial direction points at the top of tooth cusp. The microfibrils aggregate random into intermediate filaments, forming a hierarchical structure. A sketch map of the cricket tooth cusp was proposed and a detailed discussion was given in this paper., 5 pages, 7 figures. Already submitted to Chines Physics C

We have employed ab-initio plane-wave pseudopotential density functional theory to calculate the equilibrium lattice parameters, elastic constants, under the hydrostatic pressures from 0 to 100 GPa for P1 -IrB with Pnma space group and P5 -IrB2 with Pmmn structures. Results show that the P1 -IrB structure is stable, and the incompressibility is enhanced with the increase of pressure. And the elastic constants, bulk modulus, shear modulus for P5 -IrB2 structure exhibit the regular changes under the hydrostatic pressures from 0 to 100 GPa. But when the pressure becomes 50 GPa, the Young's modulus and the lattice constant in the direction b for P5 -IrB2 structure will change exceptionally. Results show that both are not of obvious band gaps in P1 -IrB and P5 -IrB2 electronic structures under zero pressure, because of the covalent effect between Ir and B atoms. The analysis of band structure and the figure of density of states for P1 -IrB and P5 -IrB2 indicate that the two kinds of structure have metal properties.

The cricket is a truculent insect with stiff and sharp teeth as a fighting weapon. The structure and possible biomineralization of cricket teeth are always interesting. Synchrotron radiation X-ray fluorescence, X-ray diffraction, and small angle X-ray scattering techniques were used to probe the element distribution, possible crystalline structures and size distribution of scatterers in cricket teeth. A scanning electron microscope was used to observe the nanoscaled structure. The results demonstrate that Zn is the main heavy element in cricket teeth. The surface of a cricket tooth has a crystalline compound like ZnFe2(AsO4)2(OH)2(H2O)4. The interior of the tooth has a crystalline compound like ZnCl2, which is from the biomineralization. The ZnCl2-like biomineral forms nanoscaled microfibrils and their axial direction points towards the top of the tooth cusp. The microfibrils aggregate randomly into intermediate filaments, forming a hierarchical structure. A sketch map of the cricket tooth cusp is proposed and a detailed discussion is given in this paper.

The structural, elastic, electronic and optical properties of MgS B2 crystal under high pressure are studied by accurate first-principles plane wave pseudo-potential method which is based on the density functional theory. Our results show that the conduction band of the structure has a shift tendency toward higher energy, and the valence band has a shift tendency toward lower energy under high pressure. We analyze the optical properties associated with the partial density of states and the shift of energy level under high pressure. At the same time, the absorption spectrum of the MgS B2 crystal has an evident blue shift.

TiO2 nanoparticles were prepared by sol-gel method，and were annealed at different temperatures from 300 to 800℃. Their interfacial and fractal characteristics as well as and phase transition were investigated by using synchrotron radiation SAXS and XRD techniques. The change of nanoparticle size with annealing temperature was determined. The relationship between the interfacial characteristics and phase transition was discussed in this paper.