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Background The aim of this study is to investigate role of Visfatin, one of the pro-inflammatory adipokines, in sepsis-induced intestinal injury and to clarify the potential mechanism. Methods C57BL/6 mice underwent cecal ligation and puncture (CLP) surgery to establish sepsis model in vivo. Intestinal epithelial cells were stimulated with LPS to mimic sepsis-induced intestinal injury in vitro. FK866 (the inhibitor of Visfatin) with or without XMU-MP-1 (the inhibitor of Hippo signaling) was applied for treatment. The expression levels of Visfatin, NF-κB and Hippo signaling pathways-related proteins were detected by western blot or immunohistochemistry. The intestinal cell apoptosis and intestinal injury were investigated by TUNEL staining and H&E staining, respectively. ELISA was used to determine the production of inflammatory cytokines. Results The expression of Visfatin increased in CLP mice. FK866 reduced intestinal pathological injury, inflammatory cytokines production, and intestinal cell apoptosis in sepsis mice. Meanwhile, FK866 affected NF-κB and Hippo signaling pathways. Additionally, the effects of FK866 on inflammatory response, apoptosis, Hippo signaling and NF-κB signaling were partly abolished by XMU-MP-1, the inhibitor of Hippo signaling. In vitro experiments also revealed that FK866 exhibited a protective role against LPS-induced inflammatory response and apoptosis in intestinal cells, as well as regulating NF-κB and Hippo signaling, whereas addition of XMU-MP-1 weakened the protective effects of FK866. Conclusion In short, this study demonstrated that inhibition of Visfatin might alleviate sepsis-induced intestinal injury through Hippo signaling pathway, supporting a further research on Visfatin as a therapeutic target.

The electronic and magnetic characteristics of two-dimensional materials have been the focus of attention in order to a wider range of spintronic applications. By using first-principles calculations, H atomic adsorption converts single-layer FePS3 from semiconductor to half-metal while Li makes it to metal. We also find that the magnetic ground state of intrinsic FePS3 can be converted from antiferromagnetic to ferromagnetic by adsorbing H atoms, while alkali-metal atoms have no effect on it. Furthermore, the magnetic ground state is found sensitive to the numbers of H adatom on the surface of FePS3 and demonstrates a vibration behavior. The present findings regarding a surface-adsorption-tuned bandgap and magnetism controlled by the adsorption concentration in a two-dimensional van der Waals magnets could lead to potential applications in next-generation magnetic memory storage, sensors and spintronic.

Since the beginning of the 21st century, the geoscience research has been entering a significant transitional period with the establishment of a new knowledge system as the core and with the drive of big data as the means. It is a revolutionary leap in the research of geoscience knowledge discovery from the traditional encyclopedic discipline knowledge system to the computer-understandable and operable knowledge graph. Based on adopting the graph pattern of general knowledge representation, the geoscience knowledge graph expands the unique spatiotemporal features to the Geoscience knowledge, and integrates geoscience knowledge elements, such as map, text, and number, to establish an all-domain geoscience knowledge representation model. A federated, crowd intelligence-based collaborative method of constructing the geoscience knowledge graph is developed here, which realizes the construction of high-quality professional knowledge graph in collaboration with global geo-scientists. We also develop a method for constructing a dynamic knowledge graph of multi-modal geoscience data based on in-depth text analysis, which extracts geoscience knowledge from massive geoscience literature to construct the latest and most complete dynamic geoscience knowledge graph. A comprehensive and systematic geoscience knowledge graph can not only deepen the existing geoscience big data analysis, but also advance the construction of the high-precision geological time scale driven by big data, the compilation of intelligent maps driven by rules and data, and the geoscience knowledge evolution and reasoning analysis, among others. It will further expand the new directions of geoscience research driven by both data and knowledge, break new ground where geoscience, information science, and data science converge, realize the original innovation of the geoscience research and achieve major theoretical breakthroughs in the spatiotemporal big data research.

As an important contributor to the habitability of our planet, the oxygen cycle is interconnected with the emergence and evolution of complex life and is also the basis to establish Earth system science. Investigating the global oxygen cycle provides valuable information on the evolution of the Earth system, the habitability of our planet in the geologic past, and the future of human life. Numerous investigations have expanded our knowledge of the oxygen cycle in the fields of geology, geochemistry, geobiology, and atmospheric science. However, these studies were conducted separately, which has led to one-sided understandings of this critical scientific issue and an incomplete synthesis of the interactions between the different spheres of the Earth system. This review presents a five-sphere coupled model of the Earth system and clarifies the core position of the oxygen cycle in Earth system science. Based on previous research, this review comprehensively summarizes the evolution of the oxygen cycle in geological time, with a special focus on the Great Oxidation Event (GOE) and the mass extinctions, as well as the possible connections between the oxygen content and biological evolution. The possible links between the oxygen cycle and biodiversity in geologic history have profound implications for exploring the habitability of Earth in history and guiding the future of humanity. Since the Anthropocene, anthropogenic activities have gradually steered the Earth system away from its established trajectory and had a powerful impact on the oxygen cycle. The human-induced disturbance of the global oxygen cycle, if not controlled, could greatly reduce the habitability of our planet.

Three novel phosphorescent host materials, 4′,4‴-(4-phenylpyridine-2,6-diyl)bis(N,N-diphenyl-[1,1′-biphenyl]-4-amine) (P1), 2,6-bis(4′-(naphthalen-1-yl)-[1,1′-biphenyl]-4-yl)-4-phenylpyridine (P2), and 2,6-bis(3′,5′-dimethyl-[1,1′-biphenyl]-4-yl)-4-phenylpyridine (P3), based on triphenylpyridine with a symmetrical molecular conformation were designed and synthesized from 2,6-bis(4-bromophenyl)-4-phenylpyridine (3) reacting with [4-(diphenylamino)phenyl]boronic acid (A1), [4-(naphthalen-1-yl)phenyl]boronic acid (A2), and (3,5-dimethylphenyl)boronic acid (A3) through Suzuki coupling reaction, respectively. The compounds obtained were characterized by elemental analysis, 1H NMR, and 13C NMR spectroscopy. The thermal properties of these materials were studied by thermogravimetric analysis and differential scanning calorimetry measurements, which showed that they exhibited excellent thermal stability with glass transition temperatures over 94 °C. Their photophysical properties were also investigated, and the results indicated that all compounds possessed considerably high triplet energy level greater than 2.6 eV; they also emitted blue fluorescence in different solvents. Finally, the results of the density function theory calculations revealed that the compound P1 showed the well-separated frontier molecular orbital, which indicated that it possessed bipolar carrier transport ability for holes and electrons, whereas the compound P2 and P3 exhibited greater overlap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital.

Geological samples must be archived for all if we are to solve the riddles of Earth’s complex history. Geological samples must be archived for all if we are to solve the riddles of Earth’s complex history.

Four novel host materials C1–C4 based on carbazole derivatives have been designed, synthesized, characterized, and applied as organic light-emitting devices. This report presents a novel approach, which combines carbazole and aromatic hydrocarbons through methylene. The formed molecules exhibited twisted structures, which resulted in high glass transition temperatures (Tg), ranged from 90.4 to 148.0 °C. They also had high optical bandgaps (Eg), their optical energy bandgaps are determined by absorption edge technique as 3.22 to 3.50 eV, evaluated photo-physical properties of these synthesized novel chromophores, the optical properties such as maximum absorption and emission wavelengths (λ, nm), molar extinction coefficients (e, cm− 1 M− 1), Stoke’s shifts (ΔλST, nm), and quantum yields (φF) also studied the effect of solvent polarity on absorption and emission of these carbazole derivatives, and these compounds exhibited intense absorption bonds between 250 and 325 nm, which are attributed to the π–π* transition of the carbazole-centered units. In addition, they showed blue fluorescence in different solvents. These compounds showed bathochromic shift with the increase in the solvent polarity.

A new plastic–damage constitutive model based on the combination of damage mechanics and classical plastic theory was developed to simulate the failure of concrete. In order to explain different material behaviors of concrete under tensile and compressive loadings, the plastic yield criterion, the different kinematic hardening rule for tension and compressive and the isotropic flow rule were established in the effective stress space. Meanwhile, two different empirical damage evolution equations were adopted: one for compression and the other for tension. A multi-axial damage influence factor was also introduced to fully describe the anisotropic damage of concrete. Finally, the model response was compared with a wide range of experiment results. The results showed that the model could well describe the nonlinear behavior of concrete in a complex stress state.

Lumbar spinal fusion using rigid rods is a common surgical technique. However, adjacent segment disease and other adverse effects can occur. Dynamic stabilization devices preserve physiologic motion and reduce painful stress but have a high rate of construct failure and reoperation. Polyetheretherketone (PEEK) rods for semi-rigid fusions have a similar stiffness and adequate stabilization power compared with titanium rods, but with improved load sharing and reduced mechanical failure. The purpose of this paper is to review and evaluate the clinical and biomechanical performance of PEEK rods. A systematic review of clinical and biomechanical studies was conducted. A literature search using the PubMed, EMBASE, and Cochrane Library databases identified studies that met the eligibility criteria. Eight clinical studies and 15 biomechanical studies were included in this systematic review. The visual analog scale and the Oswestry disability index improved significantly in most studies, with satisfactory fusion rates. The occurrence of adjacent segment disease was low. In biomechanical studies, PEEK rods demonstrated a superior load-sharing distribution, a larger adjacent segment range of motion, and reduced stress at the rod-screw/screw-bone interfaces compared with titanium rods. The PEEK rod construct was simple to assemble and had a reliable in vivo performance compared with dynamic devices. The quality of clinical studies was low with confounding results, although results from mechanical studies were encouraging. There is no evidence strong enough to confirm better outcomes with PEEK rods than titanium rods. More studies with better protocols, a larger sample size, and a longer follow-up time are needed.

The Lopingian is one of the fastest rising periods of seawater strontium isotopic ratios (87Sr/86Sr) in earth history, and its mechanisms and increasing rates of the 87Sr/86Sr evolution were still disputed widely. These disputations among researchers were caused mainly by timeframe selection (sections’ thickness or data of radiometric ages), and different stratigraphic boundaries and un-upmost dated ages. This paper examined published 87Sr/86Sr data of the Lopingian, and projected them on timescales based on evolutionary and age constrained conodonts fossils. 87Sr/86Sr evolution vs fossil constraining timescales was re-established in this period. This research suggests: (1) 87Sr/86Sr excursion projects on fossil zones can truly support 87Sr/86Sr evolutionary pattern in the period; (2) 87Sr/86Sr evolution provides a new approach for stratigraphic research of marine carbonate sections in lieu of biostratigraphic data; (3) 87Sr/86Sr stratigraphy works on marine carbonate sections of different sedimentation rates even between different basins; (4) the 87Sr/86Sr data and its shift was dependent on samples materials and chemical treatment methods; (5) the increasing rate of marine water 87Sr/86Sr in the Late Permian is suggested as 5.4×10−5/Ma or slightly lower; (6) sedimentation age and its 87Sr/86Sr of the Lopingian marine carbonate suggested as: DPRO=259-(RS−0.70695)/5.4×10−5±1 Ma.

Browning white adipocytes may be a new target in anti-obesity therapy. Pentamethylquercetin (PMQ) has been shown to have anti-obesity effects in monosodium glutamate-induced obese mice. Here, we aimed to study the anti-obesity effects of PMQ in vitro and in vivo and to determine if adipose browning is involved in the mechanism underlying the anti-obesity effects of PMQ. We evaluated the effects of PMQ on cell proliferation, cell differentiation, glucose consumption, cellular lipid metabolism, and related brown gene expression in 3T3-L1 adipocytes. We also investigated the effects of PMQ in a mouse model of high-fat diet (HFD)-induced obesity. Our results demonstrated that PMQ increased the consumption of glucose, inhibited the accumulation of cellular triglycerides (TGs), and induced the expression of brown adipocyte-specific genes, such as uncoupling protein 1 (UCP-1), during the early stage of differentiation in 3T3-L1 adipocytes. In HFD mice, PMQ treatment reduced waist circumference, LEE index, white adipose tissue (WAT) weight and white adipocyte size and increased brown adipose tissue (BAT) weight. Moreover, PMQ treatment induced mitochondrial biogenesis and upregulated UCP-1 expression in WAT. These findings suggest that PMQ may induce browning of adipose tissue, a phenomenon that is at least partly related to its anti-obesity effects.

WirelessHART is considered to be one of the most promising wireless network protocols for its high robustness comparing to other similar wireless networks. The high robustness comes from its unique routing protocol and redundant superframe scheduling scheme. This paper focuses on the time-slot scheduling and channel assignment of WirelessHART and a graph route-based superframe scheduling scheme is proposed. In order to improve the communication reliability, our scheme applies hop-level retransmission mechanism in a multi-hop and multi-channel circumstance. Moreover, time-slot conflict and channel interference are considered and an effective solution strategy is proposed. To meet the real-time communication requirements, time-slots are assigned in the order of actual communication sequence which can effectively reduce the retransmission delay. Further more, we propose the implementation algorithm of our scheme. The performance analysis shows that our scheduling scheme has a higher robustness than the traditional non-redundancy scheme.

Free-standing optoelectronic graphene–CdS–graphene oxide (G–CdS–GO) composite papers were prepared by vacuum-assisted self-assembly. G–CdS hybrids were first prepared by a hydrothermal method and GO acts as a dispersant which makes it easier to disperse them to form relatively stable aqueous suspensions for fabricating paper. Transmission electron microscopy shows that CdS quantum dots (QDs) with an average size of approximately 1–2 nm were distributed uniformly on the graphene sheets. Photoluminescence measurements for the as-prepared G–CdS–GO composite paper showed that the surface defect related emissions of attached CdS QDs decrease and blue shift obviously due to the change in particle size and the interaction of the surface of the CdS QDs with both the GO and the graphene sheets. The resulting paper holds great potential for applications in thin film solar cells, sensors, diodes, and so on.

A kind of structure and a design method using transmission voltage-switch theory for pulse-triggered flip-flops were proposed, which are suitable for all kinds of pulse-triggered flip-flops and no extra techniques are needed to eliminate the switching activities of internal nodes. Based on the proposed structure and design technique, two pulsed flip-flops were implemented and simulated. The proposed pulsed flip-flops have simple circuit structures. HSPICE simulation shows that the proposed pulsed D flip-flop outperforms the conventional pulsed D flip-flop by 17.2% in delay and 30.1% in power-delay-product (PDP) and the proposed pulsed JK flip-flop has low power and small PDP compared with pulsed D pulsed flip-flops, confirming that the proposed structure and design technique are simple and practical.

The Neoproterozoic-Cambrian (N-C) and Permian-Triassic (P-T) transitions have been regarded the two most critical transitions in earth history because of the explosive biological radiation in the early Cambrian (the Cambrian Explosion) and the largest mass extinction at the end-Permian. Previous studies suggest that these two critical transitions showed certain comparability in major evolutionary events. In other words, a series of biological, geological, and geochemical events that had happened in the N-C transition occurred repeatedly during the P-T transition. Those events included continental re-configuration related to the deep mantle dynamics, global-scale glaciations, large C-, Sr-, and S-isotope perturbations indicating atmospheric and oceanic changes, abnormal precipitation of carbonates, and associated multiple biological radiations and mass extinctions. The coupling of those events in both N-C and P-T transitions suggests that deep mantle dynamics could be a primary mechanism driving dramatic changes of environment on the earth’s surface, which in turn caused major biological re-organizations. A detailed comparison of those events during the two critical transitions indicates that despite their general comparability, significant differences do exist in magnitude, duration, and frequency. The supercontinent Rodinia began to rift before the Snowball Earth time. By contrast, the supercontinent Pangea entered the dispersal stage after the greatest glaciation from the Late Carboniferous to Cisuralian. Quantitative data and qualitative analyses of different fossil groups show a more profound mass extinction during the N-C transition than at the end-Permian in terms of ecosystem disruption. This is indicated by the disappearance of the whole Ediacaran biota at the N-C boundary. The subsequent appearances of many new complex animals at phylum level in the early Cambrian mark the establishment of a brand new ecosystem. However, the end-Permian mass extinction is manifested mainly by the extinction of many different taxa at class and order levels. Although it caused the extinction of 95% of marine species and 75% of terrestrial species as well as complete cessation of coal and reef deposits after the mass extinction, this high-level biological re-organization still occurred within an established ecosystem, however drastic it may seem. Survived or Lazarus taxa re-occupied the existing ecospace in a relatively short duration after the end-Permian mass extinction. C-isotope excursions display large perturbations during both transitions, yet also in different magnitudes and frequencies, which suggest different atmospheric and oceanic conditions. The recurrent geological and geochemical events as well as the coupled major biological turnovers during the two transitions provide new clues to understanding the interplays among the earth-life system. Thus, it is essential to carry out multidisciplinary studies from the deep internal system to the surface of the Earth as a whole in order to unravel the interactions of different spheres of the earth.

By applying switch-signal theory, the theory of transmission current-switches based on symmetric ternary logic is proposed, this theory is suitable to design symmetric ternary current-mode CMOS circuits. The symmetric ternary current-mode CMOS circuits designed by using this theory not only have simpler circuit structures and correct logic functions, but also can process bidirectional signals.

A new numerical algorithm for acoustic noise generation is developed. The approach involves two steps comprising an incompressible flow part and an inviscid acoustic part. The acoustic part can be started at any time of the incompressible computation. The formulation can be applied both for isentropic flows and non-isentropic flows. The model is validated for the cases of an isentropic pulsating sphere and non-isentropic flows past a circular cylinder. In the latter case the computations show that the generated acoustic field in addition to the dominant Strouhal frequency, f0, contains a slightly higher frequency, f2, and a modulating lower frequency, f1=f2−f0. Numerical experiments with different interpolation schemes, boundary conditions, etc., show that the appearance of these modes is not an artifact from the numerical discretization.

Improved thermoanalytical methods have been developed that are capable of quantitative identification of various components of fly ash from a laboratory-scale fluidized bed combustion system. The thermogravimetric procedure developed can determine quantities of H2O, Ca(OH)2, CaCO3, CaSO4 and carbonaceous matter in fly ash with accuracy comparable to more time-consuming ASTM methods. This procedure is a modification of the Mikhail-Turcotte methods that can accurately analyze bed ash, with higher accuracy regarding the greater amount of carbonaceous matter in fly ash. In addition, in conjunction with FTIR and SEM/EDS analyses, the reduction mechanism of CaSO4 as CaSO4+4H2 ↔ CaS + 4H2O has been confirmed in this study. This mechanism is important in analyzing and evaluating sulfur capture in fluidized-bed combustion systems.