5,546 research outputs found

    Managing The Combination Of Nonalcoholic Fatty Liver Disease And Metabolic Syndrome With Chinese Herbal Extracts In High-fat-diet Fed Rats

    Get PDF
    Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome (MetS). The aim of the study was to evaluate the effects of Chinese herbal extracts from Salvia miltiorrhiza and Gardenia jasminoides (SGE) on the combination of NAFLD and MetS induced by a high-fat diet (HFD) in rats. After 6 weeks of HFD feeding, rats ( each group) were treated with saline, rosiglitazone (RSG), and SGE for 4 weeks. HFD rats were obese, hyperinsulinemic, hyperlipidemic and increased hepatic enzymes with the histological images of NAFLD. Treatment with SGE significantly reduced serum triglycerides (TG), nonesterified fatty acids and enhanced insulin sensitivity, and ameliorated the elevated serum hepatic enzymes compared with HFD-saline group. SGE treatment also attenuated hepatic TG by 18.5% (). Histological stains showed SGE decreased lipids droplets in hepatocytes () and normalized macrovesicular steatosis in HFD rats. Significant reduction of TNF-a and IL6 in adipose tissue was detected in SGE treated rats. The anti-inflammatory action may be, at least in part, the mechanism of SGE on MetS associated with NAFLD. This study discovered that SGE is capable of managing metabolic and histological abnormalities of NAFLD and MetS. SGE may be an optimal treatment for the combination of NAFLD and MetS

    Optical signature of symmetry variations and spin-valley coupling in atomically thin tungsten dichalcogenides

    Get PDF
    Motivated by the triumph and limitation of graphene for electronic applications, atomically thin layers of group VI transition metal dichalcogenides are attracting extensive interest as a class of graphene-like semiconductors with a desired band-gap in the visible frequency range. The monolayers feature a valence band spin splitting with opposite sign in the two valleys located at corners of 1st Brillouin zone. This spin-valley coupling, particularly pronounced in tungsten dichalcogenides, can benefit potential spintronics and valleytronics with the important consequences of spin-valley interplay and the suppression of spin and valley relaxations. Here we report the first optical studies of WS2 and WSe2 monolayers and multilayers. The efficiency of second harmonic generation shows a dramatic even-odd oscillation with the number of layers, consistent with the presence (absence) of inversion symmetry in even-layer (odd-layer). Photoluminescence (PL) measurements show the crossover from an indirect band gap semiconductor at mutilayers to a direct-gap one at monolayers. The PL spectra and first-principle calculations consistently reveal a spin-valley coupling of 0.4 eV which suppresses interlayer hopping and manifests as a thickness independent splitting pattern at valence band edge near K points. This giant spin-valley coupling, together with the valley dependent physical properties, may lead to rich possibilities for manipulating spin and valley degrees of freedom in these atomically thin 2D materials

    Tectonic affinity of the west Qinling terrane (central China): North China or Yangtze?

    Get PDF
    [33] Neogene (̃14 Ma) basaltic magmatism has occurred in west Qinling, at the northeastern corner of the Tibetan Plateau. Furthermore, U-Pb ages and Hf isotopic data of xenocrystic zircons indicate that the unexposed Neoarchean (2.7-2.5 Ga) basement beneath the Phanerozoic outcrops in west Qinling has affinities with the southern margin of the north China block. The basement has a complex evolution, including the addition of juvenile mantle material at ̃2.7- 2.4 Ga and 1.1-0.8 Ga and reworking at ̃1.8 Ga and possibly at 1.4 Ga. Phanerozoic thermal events at 320-300 Ma, 230 Ma, and 160 Ma also have affected the basement. We interpret the west Qinling orogenic terrane as originally separated from the north China block, joined to the northern Yangtze block during the Meso-Neoproterozoic, and finally involved in the northward subduction and collision of the Yangtze block in the Paleozoic and early Mesozoic and subsequent lithospheric extension in the Jurassic. © 2010 by the American Geophysical Union.published_or_final_versio

    Share Our Cultural Heritage (SOCH): Worldwide 3D Heritage Reconstruction and Visualization via Web and Mobile GIS

    Get PDF
    Despite being of paramount importance to humanity, tangible cultural heritage is often at risk from natural and anthropogenic threats worldwide. As a result, heritage discovery and conservation remain a huge challenge for both developed and developing countries, with heritage sites often inadequately cared for, be it due to a lack of resources, nonrecognition of the value by local people or authorities, human conflict, or some other reason. This paper presents an online geo-crowdsourcing system, termed Share Our Cultural Heritage (SOCH), which can be utilized for large-scale heritage documentation and sharing. Supported by web and mobile GIS, cultural heritage data such as textual stories, locations, and images can be acquired via portable devices. These data are georeferenced and presented to the public via web-mapping. Using photogrammetric modelling, acquired images are used to reconstruct heritage structures or artefacts into 3D digital models, which are then visualized on the SOCH web interface to enable public interaction. This end-to-end system incubates an online virtual community to encourage public engagement, raise awareness, and stimulate cultural heritage ownership. It also provides valuable resources for cultural heritage exploitation, management, education, and monitoring over time

    Phase transitions and critical behavior of black branes in canonical ensemble

    Full text link
    We study the thermodynamics and phase structure of asymptotically flat non-dilatonic as well as dilatonic black branes in a cavity in arbitrary dimensions (DD). We consider the canonical ensemble and so the charge inside the cavity and the temperature at the wall are fixed. We analyze the stability of the black brane equilibrium states and derive the phase structures. For the zero charge case we find an analog of Hawking-Page phase transition for these black branes in arbitrary dimensions. When the charge is non-zero, we find that below a critical value of the charge, the phase diagram has a line of first-order phase transition in a certain range of temperatures which ends up at a second order phase transition point (critical point) as the charge attains the critical value. We calculate the critical exponents at that critical point. Although our discussion is mainly concerned with the non-dilatonic branes, we show how it easily carries over to the dilatonic branes as well.Comment: 37 pages, 6 figures, the validity of using the effective action discussed, references adde

    Electronic transitions of iron in almandine-composition glass to 91 GPa

    Get PDF
    Valence and spin states of Fe were investigated in a glass of almandine (Fe3_3Al2_2Si3_3O12_{12}) composition to 91 GPa by X-ray emission spectroscopy and energy- and time-domain synchrotron Mössbauer spectroscopy in the diamond-anvil cell. Changes in optical properties, total spin moment and Mössbauer parameters all occur predominantly between 1 bar and ~30 GPa. Over this pressure range, the glass changes from translucent brown to opaque and black. The total spin moment of the glass derived from X-ray emission spectroscopy decreases by ~20%. The complementary Mössbauer spectroscopy approaches reveal consistent changes in sites corresponding to 80–90% Fe2+^{2+} and 10–20% Fe3+^{3+}. The high-spin Fe2+^{2+} doublet exhibits a continuous decrease in isomer shift and increase in line width and asymmetry. A high-spin Fe3+^{3+} doublet with quadrupole splitting of ~1.2 mm/s is replaced by a doublet with quadrupole splitting of ~1.9 mm/s, a value higher than all previous measurements of high-spin Fe3+^{3+} and consistent with low-spin Fe3+^{3+}. These observations suggest that Fe3+^{3+} in the glass undergoes a continual transition from a high-spin to a low-spin state between 1 bar and ~30 GPa. Almandine glass is not expected to undergo any abrupt transitions in electronic state at deep mantle pressures.National Science FoundationThis is the author accepted manuscript. The final version is available from the Mineralogical Society of America via http://dx.doi.org/10.2138/am-2016-560

    Ageing memory and glassiness of a driven vortex system

    Full text link
    Many systems in nature, glasses, interfaces and fractures being some examples, cannot equilibrate with their environment, which gives rise to novel and surprising behaviour such as memory effects, ageing and nonlinear dynamics. Unlike their equilibrated counterparts, the dynamics of out-of- equilibrium systems is generally too complex to be captured by simple macroscopic laws. Here we investigate a system that straddles the boundary between glass and crystal: a Bragg glass formed by vortices in a superconductor. We find that the response to an applied force evolves according to a stretched exponential, with the exponent reflecting the deviation from equilibrium. After the force is removed, the system ages with time and its subsequent response time scales linearly with its age (simple ageing), meaning that older systems are slower than younger ones. We show that simple ageing can occur naturally in the presence of sufficient quenched disorder. Moreover, the hierarchical distribution of timescales, arising when chunks of loose vortices cannot move before trapped ones become dislodged, leads to a stretched-exponential response.Comment: 16 pages, 5 figure

    DOCUMENTATION OF HERITAGE STRUCTURES THROUGH GEO-CROWDSOURCING AND WEB-MAPPING

    Get PDF
    Heritage documentation has become increasingly urgent due to both natural impacts and human influences. The documentation of countless heritage sites around the globe is a massive project that requires significant amounts of financial and labour resources. With the concepts of volunteered geographic information (VGI) and citizen science, heritage data such as digital photographs can be collected through online crowd participation. Whilst photographs are not strictly geographic data, they can be geo-tagged by the participants. They can also be automatically geo-referenced into a global coordinate system if collected via mobile phones which are now ubiquitous. With the assistance of web-mapping, an online geo-crowdsourcing platform has been developed to collect and display heritage structure photographs. Details of platform development are presented in this paper. The prototype is demonstrated with several heritage examples. Potential applications and advancements are discussed

    Intervention effects of Ganoderma lucidum spores on epileptiform discharge hippocampal neurons and expression of Neurotrophin-4 and N-Cadherin

    Get PDF
    Epilepsy can cause cerebral transient dysfunctions. Ganoderma lucidum spores (GLS), a traditional Chinese medicinal herb, has shown some antiepileptic effects in our previous studies. This was the first study of the effects of GLS on cultured primary hippocampal neurons, treated with Mg2+ free medium. This in vitro model of epileptiform discharge hippocampal neurons allowed us to investigate the anti-epileptic effects and mechanism of GLS activity. Primary hippocampal neurons from <1 day old rats were cultured and their morphologies observed under fluorescence microscope. Neurons were confirmed by immunofluorescent staining of neuron specific enolase (NSE). Sterile method for GLS generation was investigated and serial dilutions of GLS were used to test the maximum non-toxic concentration of GLS on hippocampal neurons. The optimized concentration of GLS of 0.122 mg/ml was identified and used for subsequent analysis. Using the in vitro model, hippocampal neurons were divided into 4 groups for subsequent treatment i) control, ii) model (incubated with Mg2+ free medium for 3 hours), iii) GLS group I (incubated with Mg2+ free medium containing GLS for 3 hours and replaced with normal medium and incubated for 6 hours) and iv) GLS group II (neurons incubated with Mg2+ free medium for 3 hours then replaced with a normal medium containing GLS for 6 hours). Neurotrophin-4 and N-Cadherin protein expression were detected using Western blot. The results showed that the number of normal hippocampal neurons increased and the morphologies of hippocampal neurons were well preserved after GLS treatment. Furthermore, the expression of neurotrophin-4 was significantly increased while the expression of N-Cadherin was decreased in the GLS treated group compared with the model group. This data indicates that GLS may protect hippocampal neurons by promoting neurotrophin-4 expression and inhibiting N-Cadherin expression
    • …
    corecore