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This study examines the woody plant community in the Sygera Mountains to reveal the diversity changes and phylogenetic structure of woody plants in different vertical zones. Three plots of 400 m2 and two plots of 900 m2 are set up in each zone. The line transect method is used to supplement the woody plant species list. Meteorological data are adopted to analyze the composition of woody plant flora, the characteristics of the phylogenetic structure, and their relationship with annual average temperature. Results showed that (1) temperate woody plants account for a large proportion (65.6%) in the woody plant community of the Sygera Mountains, and widespread woody genera account for a small proportion (12.6%). The composition of families and genera is rich in the mountainous warm temperate zone, and the species composition is rich in the mountainous temperate zone. (2) The Gleason index and phylogenetic diversity of the woody plant communities in the five vertical zones are significantly positively correlated with the annual average temperature (P < 0.01), whereas the net relatedness and nearest taxon indices are not correlated with the annual average temperature. (3) The woody plant communities in the alpine frigid and alpine desert zones of the Sygera Mountains exhibit phylogenetic clustering, which suggests that habitat filtering plays an important role in the construction of woody plant communities in these vertical zones. However, the other vertical zones show either phylogenetic clustering or phylogenetic overdispersion, indicating that the results might be the combined effects of habitat filtering and competitive exclusion. This study provides new insights into the diversity composition and construction mechanisms of woody plant communities in the Sygera Mountains. [ABSTRACT FROM AUTHOR]

Compact aero-engines that use centrifugal compressors are in high demand due to their small size and cost-effectiveness. However, limited improvements in the aerodynamic performance of centrifugal impellers have led to a greater focus on improving the performance of diffusers. This paper introduces a novel vane conformal diffuser designed to match an impeller with a high pressure ratio. The diffuser utilizes a unique design method that creates transitions from a twodimensional meridian to a three-dimensional configuration, to achieve a twisted design for the vane and hub. Eventually an integrated vane configuration is formed from the radial section to the bend and axial sections. The novel diffuser significantly reduces the radial size of the entire compressor compared with a conventional vaned diffuser. Different cross-section area distributions are studied to explore the reasonable static pressure recovery ability of the diffuser. To validate the new concept, the diffusers of two existing high-pressure centrifugal compressors are redesigned using the novel conformal diffuser configuration. The numerical results show that the aerodynamic performances of the two redesigned centrifugal compressors are improved in terms of both the total pressure ratio and the isentropic efficiency compared with their counterparts. These results demonstrate the effectiveness and applicability of the developed design method for the novel conformal diffuser. [ABSTRACT FROM AUTHOR]

The study of phylogenetic zones of plants provides a good insight into the biogeographic and ecological processes of zone formation and a clear understanding of the nature and origin of biodiversity hotspots. The literature in the Web of Science core dataset was analyzed using bibliometric methods combined with CiteSpace 5.0, VOSviewer 1.6.18 visualization software, and Excel software to reveal the characteristics, hotspots, and evolutionary trends of this field over the past 35 years (1988-2022). The research on plant phylogenetic systematics has been increasing at China and abroad, and the main research force is mainly in the United States. The research conducted in this field primarily centers on biology, which exhibits clear interdisciplinary features, and the relationship between biology and other fields is particularly strong. In the field of plant phylogeny, these topics have a strong relationship in terms of knowledge transmission at each stage. The integration of diverse disciplines to advance mechanistic investigations, the amalgamation of various research techniques with phylogenetic tree building, and the utilization of model predictions across different plant species will continue to be a prominent research avenue in the realm of plant phylogenetic lineage research for the foreseeable future. [ABSTRACT FROM AUTHOR]

To scientifically and objectively evaluate the safety and stability of undersea tunnel traffic system, the risk factors and their coupling effects of undersea tunnel traffic accidents are analyzed from 5 aspects of driver, management, road, environment and vehicle by using the fault tree analysis method. In view of the abrupt evolution characteristics of the undersea tunnel traffic accident risk coupling, human factor and physical factor are taken as control variables, and system safety is taken as the state variable to construct a cusp catastrophe model of undersea tunnel traffic accident risk coupling, and the evolution mechanism of traffic accident risk coupling is explained. Selecting 18 traffic accident risk factors as the bottom indicators, and constructing a risk coupling evaluation indicator system of undersea tunnel traffic accident in 3 levels. The quantitative calculation model of risk factors coupling degree is established following the complementary principle. Combined with the application example, the evaluation results show that the evaluation method of undersea tunnel traffic accident risk coupling based on catastrophe theory is accurate and reliable, which can provide an effective theoretical reference for risk control and accident prevention of undersea tunnel traffic system. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The aim of this study was to explore the effect of micro ribonucleic acid (miR)-133b on 1-methyl-4-phenylpyridinium ion (MPP+)-induced apoptosis in the Parkinson’s disease (PD) model. MATERIALS AND METHODS: PC12 cells were induced by different concentrations of MPP+ to establish the PD cell model. Subsequently, the survival rate of PC12 cells was detected using Cell Counting Kit-8 (CCK-8) assay. Quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) was used to detect the expression of miR-133b in the PD model induced by different concentrations of MPP+. Next, PC12 cells were transfected with miR-133b mimic and miR-negative control (NC), and divided into MPP+ group, MPP+ + miR-NC group and MPP+ + miR-133b mimic group. Transfection efficiency was verified using qRT-PCR. The apoptosis of cells was detected using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. Moreover, the expressions of extracellular signal-regulated kinase 1/2 (ERK1/2) and phosphorylated (p)-ERK1/2 were determined using Western blotting. RESULTS: After MPP+ treatment, the survival rate of PC12 cells significantly declined (p<0.05). MPP+ exhibited toxicity against PC12 cells in a concentration-dependent manner. Meanwhile, cell survival rate decreased remarkably with the increase of MPP+ concentration (p<0.05). With increased concentration of MPP+, the expression of miR-133b in the PD cell model declined significantly (p<0.05). The apoptosis of PC12 cells was remarkably inhibited by overexpression of miR-133b in the PD cell model (p<0.05). In addition, the protein expression of p-ERK1/2 in PC12 cells was notably reduced after overexpression of miR-133b in the PD cell model (p<0.05). CONCLUSIONS: MiR-133b is lowly expressed in the PD cell model. Furthermore, overexpression of miR-133b inhibits cell apoptosis in the PD cell model by regulating the ERK1/2 signaling pathway. [ABSTRACT FROM AUTHOR]

Using a single diamond nitrogen-vacancy (NV) center embedded in a waveguide-coupled photonic crystal (PC) nanocavity and driven by a classical laser field, we investigate optical transmission and group delay characteristics of the hybrid system operating in the weak-coupling regime. It is found that double electromagnetically induced-transparency (EIT) transmission peaks and slow- and fast-light propagation inside the EIT-like windows can be realized with practical system parameters. The double-frequency transparency of the input light expands the frequency range of EIT and may improve the controllability of EIT in this composite PC-NV system. The present system also provides a way to achieve integrated photonic slow- and fast-light devices for applications requiring multiple EIT effect in a PC platform. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aims to investigate the potential function of miR-325-3p in vascular integrity and inflammatory response following spinal cord injury (SCI). MATERIALS AND METHODS: The protein levels of ANG-1, ANG-2, and caspase-3 in HUVECs incubated with 0, 100, 200, 400, and 800 ng/ml NE for 24 h were determined. The regulatory effect of overexpressed miR-325-3p on the protein levels of ANG-1 and ANG-2 was determined by Western blot. The SCI model in SD rats was established by spinal injury at T10. Subsequently, the relative levels of miR-325-3p, ANG-1, and ANG-2 were determined in SCI rats and controls. Furthermore, SCI rats were administrated with miR-325-3p mimics or negative control and the relative levels of miR-325-3p, ANG-1, and ANG- 2 were examined as well. At day 14, the protein levels of iNOS and GFAP in SCI rats and those overexpressing miR-325-3p were detected. BBB (Basso, Beattie, and Bresnahan) locomotor rating scale was applied for evaluating the locomotor function recovery at day 1, 3, 7, 14, 21, and 28 following SCI RESULTS: NE treatment in HUVECs downregulated ANG-1 and upregulated ANG-2 and caspase-3 in a dose-dependent manner. The overexpression of miR-325-3p upregulated NE-induced decreased the level of ANG-1 and downregulated NE-induced increased level of ANG-2. After the establishment of the SCI model in rats, the miR-325-3p level gradually decreased in SCI rats relative to controls in a time-dependent manner. ANG-1 level in SCI rats decreased to the lowest on the first day following SCI, and gradually increased at day 3, 5, and 7. ANG-2 level was firstly upregulated and achieved the peak on day 3, and then decreased at day 5 and 7. Moreover, SCI rats overexpressing miR-325-3p showed a higher level of ANG-1 and lower level of ANG-2 than those of SCI rats. Overexpression of miR-325-3p downregulated the protein levels of iNOS and GFAP in SCI rats. BBB scale showed elevated locomotor function recovery in SCI rats overexpressing miR-325-3p compared with SCI rats. CONCLUSIONS: MiR-325-3p protects the integrity of the vascular wall, reduces infiltration of inflammation, and improves locomotor function recovery at post-SCI. [ABSTRACT FROM AUTHOR]

We have formulated the size and temperature dependence of the phonon relaxation dynamics for CdS, CdSe, Bi2Se3, and Sb2Te3 nanostructures based on the framework of bond order-length-strength correlation, core-shell configuration, and local bond averaging approach. The Raman shifts are correlated directly to the identities (nature, order, length, and energy) of the representative bond of the specimen without needing involvement of the Grüneisen mode parameters or considering the processes of phonon decay or multi-phonon resonant scattering. Quantitative information of the Debye temperature, the atomic cohesive energy, the reference frequencies from which the Raman shifts proceed, and the effective coordination numbers of the randomly sized particles, as well as the length and energy of the representative bond, has been obtained. It is clarified that the size-induced phonon softening arises intrinsically from the cohesive weakening of the undercoordinated atoms in the skin up to three atomic layers and the thermally derived phonon softening results from the thermally lengthening and weakening of bonds. Developed approach empowers the Raman technique in deriving quantitative and direct information regarding bond stiffness relaxation with applied stimuli such as coordination, mechanical, thermal, and chemical environment, which are crucial to practical applications. [ABSTRACT FROM AUTHOR]

Correlation between the elastic modulus (B) and the Raman shift (Δω) of TiO2 and their responses to the variation of crystal size, applied pressure, and measuring temperature have been established as a function depending on the order, length, and energy of a representative bond for the entire specimen. In addition to the derived fundamental information of the atomic cohesive energy, binding energy density, Debye temperature and nonlinear compressibility, theoretical reproduction of the observations clarified that (i) the size effect arises from the under-coordination induced cohesive energy loss and the energy density gain in the surface up to skin depth; (ii) the thermally softened B and Δω results from bond expansion and bond weakening due to vibration; and, (iii) the mechanically stiffened B and Δω results from bond compression and bond strengthening due to mechanical work hardening. With the developed premise, one can predict the changing trends of the concerned properties with derivatives of quantitative information as such from any single measurement alone. [ABSTRACT FROM AUTHOR]

The thermoelectric performance of EuCd2Sb2 and YbCd2Sb2 was improved by mixed cation occupation. The composition, structure, and thermoelectric properties of YbxEu1-xCd2Sb2 (x=0, 0.5, 0.75, and 1) have been investigated. Polycrystalline samples are prepared by direct reaction of the elements. Thermoelectric properties were investigated after densification of the materials by spark plasma sintering. YbxEu1-xCd2Sb2 crystallizes in the P3m1 space group. The lattice parameters increase with the europium content. These materials show low electrical resistivity, high Seebeck coefficient, and low thermal conductivity together with high carrier concentration and high carrier mobility. ZT values of 0.88 and 0.97 are obtained for Yb0.5Eu0.5Cd2Sb2 and Yb0.75Eu0.25Cd2Sb2 at 650 K, respectively. [ABSTRACT FROM AUTHOR]