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The subaerial exposure of the modern continental crust through time remains intensely debated, with estimates of the first exposure ranging from the late Archean to the Neoproterozoic. To constrain when and how much of the continental crust was exposed subaerially during Earth's history, we trained a supervised machine learning model on the compositions of modern subaerial and submerged basalts. Then, we applied this well‐trained model to a refined worldwide data set of basaltic compositions and calculated the mean proportions of basalts erupted subaerially since 3.8 billion years ago (Ga). Our results suggest that ∼20% of the basalts were exposed subaerially in the early Archean, which may have driven the synthesis of biopolymers crucial to the origins and evolution of life. The proportion of subaerial basalts increased markedly during two stages between the late Archean and the Paleoproterozoic before reaching the present‐day level no earlier than ∼1.8 Ga. Plain Language Summary: Although land only covers about 30% of Earth's surface, it plays a crucial role in our planet's ecosystem by interacting with the ocean and atmosphere. Scientists are still debating when and how much land was above sea level throughout history. In our study, we used a machine learning technique to analyze the chemical compositions of basalts and classified rocks that formed on land and under water. We then used this program to study rocks from different times in Earth's history and estimate how much land was above the oceans over time. We found that about 15%–30% of the continents were above the oceans about 3.8 to 2.8 billion years ago (Ga). This may have helped life evolve by creating molecules essential for living things. The amount of land above water increased significantly during two periods between 2.8 and 1.8 Ga and reached today's level no earlier than 1.8 Ga. Key Points: Improve the geochemical data quality of global basaltic rocksMachine learning can effectively classify subaerially and subaqueously erupted basaltsThe subaerial proportion of basalts may reach present‐day level at about 1.8 billion years ago to a maximum [ABSTRACT FROM AUTHOR]

The calcium isotope composition of seawater (δ44/40Ca sw) records important information on the evolution of the calcium and carbon cycles over geologic time. Over the past two decades, many attempts have been made to reconstruct the Neogene δ44/40Ca sw variation using various calcium isotope records of seawater or seawater-like pore fluids. Nonetheless, large discrepancies still exist among these Neogene δ44/40Ca sw records. Here we report δ44/40Ca values in a suite of Neogene island dolomites (20.8–3.4 Ma, n = 18) from the South China Sea. Combining multiple geochemical proxies (δ44/40Ca, δ13C, and δ18O, this study; Sr/Ca, ∑REY, δ7Li, δ26Mg, 87Sr/86Sr, and Δ 47 , previous studies) and evidence from petrography, fluid inclusions, and magnetostratigraphy, we suggest that the dolomitization for these dolomites was buffered by seawater-like fluids in the shallow marine burial domain or even marine diagenetic domain (<180 m) over a considerable period of time (<2 Myr). Then, we apply the equilibrium calcium isotope fractionation factor between dolomite and seawater of −0.52 ± 0.20 ‰ (2SD, n = 13) estimated from the literature to these fluid-buffered dolomites and reconstruct a new Neogene δ44/40Ca sw record. After using the Locally Weighted Regression (LOWESS) curve fitting method, our dolomite-based δ44/40Ca sw record is consistent with the reconciled seawater record from other calcium isotope archives, including shark teeth, corals, foraminifera, brachiopods, barites, phosphates, and bulk pelagic carbonates. Our results support the use of fabric-retentive early marine diagenetic dolomites to trace the evolution of δ44/40Ca sw through Earth's history. [ABSTRACT FROM AUTHOR]

Objective: The third generation of antiepileptic medication (ASM) perampanel (PER), is mostly used as an add-on treatment for refractory epilepsy patients, and rarely used as a monotherapy. This study aims to observe the efficacy and assess the cognitive effects of PER monotherapy in patients with self-limited epilepsy with centrotemporal spikes (SeLECTS). Patients and Methods: Through screening, 86 patients who were first diagnosed with SeLECTS and treated with PER monotherapy were included in this study. All patients were followed up at least 12 months, and Evaluated the efficacy and safety of PER by observing the seizures of patients. At the same time, we used the P300 event-related potential (ERP) component and Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) to evaluate the cognitive changes in children before and after treatment with PER. Results: Ten percent of the children experienced adverse effects, such as dizziness, gait instability, and irritability. The drug retention rate at the last follow-up was 98.83%. Further more, the P300 ERP component and WISC-IV tests were performed no significant difference before and 12 months after PER monotherapy in SeLECTS children. Conclusion: The third-generation of ASM PER monotherapy had a clear effect in children with SeLECTS. A small dose of PER can control seizures well and has no obvious effect on cognitive development. [ABSTRACT FROM AUTHOR]

High-precision potassium (K) isotope measurements in marine carbonates allow using this novel geochemical proxy to constrain seawater chemistry through geologic time. However, these measurements are still scarce due to the challenges of low-K contents in carbonates during K ion chromatography, such as insufficient sample purification, non-quantitative yield, and high accumulative blank. Here we optimize a dual-column K purification method that addresses these challenges, achieving a satisfactory K separation using 100–150 mg carbonates for routine high-precision K isotope analysis on the Sapphire™ MC-ICP-MS. We then report K isotope compositions in multiple certified reference materials, including limestone, dolostone, coral, and basalt for future inter-laboratory comparisons. The optimized K purification method provides great potential for future K isotope studies of marine carbonates. [ABSTRACT FROM AUTHOR]

The controls on potassium (K) isotope fractionation during chemical weathering are evaluated using two regolith profiles developed over ∼350 kyr on the humid and arid sides of Kohala Mountain, Hawai'i. The humid regolith shows 145% K enrichment relative to the basaltic parent in shallow (≤1 m) horizons, but losses of up to 90% in the deeper horizons. By contrast, the arid regolith has lost between 60 and 90% K from the top 1 m of the soil with the least depletion in the deeper horizons due to limited chemical weathering. This apparent contradiction can be explained by enhanced accumulation of K-bearing mineral aerosols in the humid regolith. Bulk δ41K varies from −0.76 ± 0.08 to −0.31 ± 0.06‰ in the humid regolith compared with −0.48‰ for the underlying basalt. In contrast, the arid regolith shows δ41K values ranging from −0.39 ± 0.10 to −0.02 ± 0.05‰, heavier than that of their basaltic parent. Exchangeable (NH 4 Ac extracts) δ41K of the humid and arid regoliths ranges from −0.63 ± 0.07 to 0.11 ± 0.07‰ and −0.01 ± 0.05 to 0.04 ± 0.08‰, respectively. Exchangeable K has δ41K higher than (or similar to) the bulk values in most samples, reflecting a potential contribution of marine aerosols to the labile (plant available) K pool. In the shallow regolith, K derived from mineral aerosols is significant, especially for the humid site, and this idea is supported by enriched quartz, radiogenic Nd-Sr isotope values towards the surface, and increasing δ41K close to the upper crustal composition (an analogue of the dust). The enrichment of K in humid surface soils, an upward decrease in exchangeable δ41K in the humid regolith and plant-like δ41K in the topmost, organic-rich soils may reveal the contribution of plant cycling. Low δ41K in deep, humid regolith relative to δ41K Basalt appears to be driven by clay incorporation of isotopically light K. In comparison, higher δ41K in the arid regolith than δ41K Basalt likely reflects an interplay between preferential clay 41K sorption in alkaline environments and preservation of seawater-derived K in forms of clay adsorbed complex and carbonate phases (via adsorption and/or incorporation). Our results reveal that the K isotope composition in Hawaiian regoliths depends on climate, while it is complicated by the interaction among weathering, plant cycling and addition of marine and mineral aerosols. [ABSTRACT FROM AUTHOR]

We combine spectroscopic and geochemical approaches to interpret the fate of potassium (K) during forest soil development along a 4-million-year chronosequence sampled from relatively undisturbed rainforests in Hawai'i. Potassium derived from weathering of lava is dominant in the youngest site (0.3 ky), but its contribution to the soil K budget declines as weathering progresses. Sites older than 0.3 ky are characterized by substantial K depletion (τ K,Nb ∼−1), with soil isotopic composition (41K/39K, δ41K) varying from −1.91 ± 0.08‰ to −0.09 ± 0.08‰, relative to the homogeneous basaltic substrate (−0.48‰). Exchangeable and interlayered K show δ41K values ranging from −1.32 ± 0.06‰ to 0.06 ± 0.08‰, higher than their corresponding bulk δ41K values. The δ41K patterns of soils and exchangeable components are vertically similar, implying similar environmental controls. The variability in K phase and isotope composition reflects the accumulative effect of different processes. Chemical weathering and plant cycling retain isotopically light K in soils, in particular for 20–150 ky sites. In contrast, atmospheric inputs of marine aerosols (0.14‰) and mineral aerosols (−0.44‰) add heavier K (than native basalts) and crust-like K (similar to basaltic δ41K) in soils, respectively. In sites older than 150 ky, nearly complete depletion of basaltic K and reduced plant K imprints result in the dominance of atmospheric inputs in soils. In sum, this study emphasizes the sensitivity of δ41K to terrestrial biotic and abiotic K cycles. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the Chinese new gastric cancer screening score (i.e., Li's score) and Kyoto Classification of Gastritis for screening gastric cancer. Methods. A total of 702 patients were scored using the two scoring methods. Gastric atrophy, intestinal metaplasia, and gastric cancer (including early gastric cancer) were compared between the two scoring methods. The area under the ROC curve, sensitivity, and specificity of the two scoring methods were evaluated. Results. Both of the two scoring methods found that gastric atrophy, intestinal metaplasia, and gastric cancer (including early gastric cancer) were all significantly higher in the medium-risk and high-risk group patients than those in the low-risk group patients. According to the Kyoto Classification of Gastritis, patients in the high-risk group had more gastric atrophy, intestinal metaplasia, and gastric cancer than those in the medium-risk group patients. Gastric atrophy, intestinal metaplasia, and gastric cancer in the low-risk and medium-risk group patients evaluated by the Li score were all significantly higher than those in patients with corresponding risk level evaluated by Kyoto Classification of Gastritis, respectively. The area under the ROC curve of the Li score was 0.702, and the sensitivity and specificity were 57.6% and 85.3%, respectively. The area under the ROC curve of the Kyoto Classification of Gastritis was 0.826, and the sensitivity and specificity were 75.4% and 83.6%, respectively. Conclusion. Both Li's score and Kyoto Classification of Gastritis showed good screening value for gastric cancer, but Kyoto Classification of Gastritis was more sensitive than the Li score. [ABSTRACT FROM AUTHOR]

Background: Intestinal ischemia/reperfusion (I/R) injury commonly occurs during perioperative periods, resulting in high morbidity and mortality on a global scale. Dexmedetomidine (Dex) is a selective α2-agonist that is frequently applied during perioperative periods for its analgesia effect; however, its ability to provide protection against intestinal I/R injury and underlying molecular mechanisms remain unclear.Methods: To fill this gap, the protection of Dex against I/R injury was examined in a rat model of intestinal I/R injury and in an inflammation cell model, which was induced by tumor necrosis factor-alpha (TNF-α) plus interferon-gamma (IFN-γ) stimulation.Results: Our data demonstrated that Dex had protective effects against intestinal I/R injury in rats. Dex was also found to promote mitophagy and inhibit apoptosis of enteric glial cells (EGCs) in the inflammation cell model. PINK1 downregulated p53 expression by promoting the phosphorylation of HDAC3. Further studies revealed that Dex provided protection against experimentally induced intestinal I/R injury in rats, while enhancing mitophagy, and suppressing apoptosis of EGCs through SIRT3-mediated PINK1/HDAC3/p53 pathway in the inflammation cell model.Conclusion: Hence, these findings provide evidence supporting the protective effect of Dex against intestinal I/R injury and its underlying mechanism involving the SIRT3/PINK1/HDAC3/p53 axis. [ABSTRACT FROM AUTHOR]

To investigate isotope fractionation between biogenic carbonates and modern seawater, we measured K concentration, phase, and isotopic composition in calcified skeletons from a variety of calcifying species. Samples included deep-sea corals, hermatypic corals, bivalves, gastropods, brachiopods, and planktonic foraminifera recovered globally over the past ten years in habitats with temperatures varying from 2 to 29 °C. The δ41K values of the calcified organisms vary significantly, ranging from −0.72 ± 0.11 to 0.94 ± 0.04‰. Deep-sea corals exhibit the largest isotopic variability and the lowest δ41K, ranging from −0.72 ± 0.11 to 0.28 ± 0.09‰. Hermatypic corals display a moderate δ41K, ranging from −0.20 ± 0.07 to 0.37 ± 0.10‰. Bivalves display widely variable δ41K values from 0.04 ± 0.05 to 0.94 ± 0.04‰, including the highest δ41K observed. Gastropods exhibit δ41K values between −0.42 ± 0.06 and −0.12 ± 0.06‰, while brachiopods have δ41K values from −0.30 ± 0.05 to 0.24 ± 0.06‰. Limited foraminifera samples (n = 2) reveal δ41K values of 0.15 ± 0.06 to 0.21 ± 0.06‰. Synchrotron-based atomic analyses show that K in biogenic carbonates is dominantly hosted in amorphous K 2 CO 3 , calcite-like and aragonite-like K phases, and intracrystalline organic matrices of varying proportions. The K isotopic composition of marine biogenic carbonates is not strongly temperature-dependent, in general, but correlates with skeletal K phases. This phase-control may indicate a first-order biological control on skeletal K incorporation, partitioning, and associated K isotope fractionation. This appears to reflect a substantial "vital effect"; i.e., physiological modification of the environmental information recorded in calcifying organisms. Substantial variations in δ41K call for additional scrutiny before using marine biogenic carbonates to interpret ancient seawater δ41K composition as physiological modulation substantially complicates the interpretation of marine carbonate δ41K records through time. Future studies should include species-specific calibration with complementary synchrotron data to refine K isotope applications for paleoceanography. [ABSTRACT FROM AUTHOR]

[Display omitted] Clay adsorption is a critical process responsible for the mobilization and cycling of potassium (K) on Earth's surface. Recent studies emphasized the potential of using stable K isotopes (δ41K) to understand chemical weathering. However, the direction, degree, and mechanism of K isotopic fractionation linked to clay K uptake during chemical weathering remain poorly constrained. This work investigated the mechanism of K adsorption on clays (kaolinite and smectite) and the isotopic fractionation in three experimental sets with K-containing solutions. The time-series experiments revealed that the adsorption and isotope equilibria were attained after less than 12-hour reaction. Potassium adsorption rate slowed down and its isotopic fractionation approached the steady-state during 15-day reaction. The pH-dependent experiments demonstrated that the percentage of clay K adsorption and the isotopic composition of adsorbed K (and aqueous K) display negative linear correlations. Net isotopic fractionation between adsorbed and aqueous phases (Δ41K ad-aq) remained near-constant (0.6–0.8‰), regardless of variations in pH ranging from 4 to 10. The concentration-control experiments demonstrated that the percentage of K adsorption decreased with increasing KCl concentrations from 0.005 to 20 mM. The δ41K values of aqueous K reached the minimum of −0.53‰ after 92.7% K adsorbed (initial KCl of 0.005 mM). Potassium adsorption was substantially suppressed as ionic strength (fixed by Na+) increased from 0.001 to 0.5 M without apparent Δ41K ad-aq variations. The K K -edge XANES demonstrated that primary K incorporated in clay lattice and surface KCl derived from sorbed K+ and Cl− synchro-dehydration can be identified after drying of clays. These features indicate that adsorbed K+ was bounded onto clays as outer-sphere complexes, which can be replaced with excess Na+ at high ionic strength. Based on experimental results, we cannot distinguish specific mineralogy regulation on K isotopic fractionation. In sum, isotopically heavy K is preferentially sorbed on clay minerals. The results confirm an equilibrium fractionation path independent of reaction time, pH, ionic strength, and initial KCl concentration. Observed K isotopic fractionation is best fitted by an equilibrium isotopic fractionation law with a fractionation factor α ad-aq of 1.00075. We highlight the opposite direction of K isotopic fractionation in clay adsorption and structural incorporation during chemical weathering, and their comparative contributions should be considered for future field investigations. [ABSTRACT FROM AUTHOR]

As one of the basic supporting technologies of 5G system, wireless sensor networks technology is facing a new challenge to improve its transmission energy efficiency. This paper considers combining simultaneous wireless information and power transfer (SWIPT) technique and routing technique, and applying them to multi-hop clustered wireless sensor networks (MCWSN), where each node can decode information and harvest energy from a received radio-frequency signal. And the relay nodes in MCWSN can utilize the harvest energy to forward data to their next hop nodes according to the routing scheme. First, we formulate an energy-efficient routing problem of MCWSN with SWIPT. Then, a heuristic energy efficient cooperative SWIPT routing algorithm (EECSR) is presented to find a transmission path with the maximum energy efficiency. Specifically, in EECSR, the resource allocation problem in each hop of the path is transformed to some equivalent convex optimization problems, which are resolved via dual decomposition. Moreover, a distributed routing protocol based on EECSR is proposed. As far as we know, this is the first solution that considers energy efficiency optimization based on routing and SWIPT in MCWSN. Simulation results show that our EECSR algorithm has high energy efficiency and good robustness. And our distributed routing protocol has better real-time performance than traditional protocols. [ABSTRACT FROM AUTHOR]

• The solution of a fuzzy differential equation via differential inclusions is proved to be equal to that of the master equation of fuzzy dynamics. • The fuzzy differential inclusion is converted into the governing equation of the membership degree and solved for the membership distribution. • The Mathieu system and the rotor/stator contact system with fuzzy uncertainties are studied with the proposed method. • It is found that some long-term responses that do not exist in deterministic systems are caused by the fuzzy uncertainties. This article provides a numerical method to solve a fuzzy differential equation via differential inclusions. The method obtains response solutions with their membership distribution functions. To do that, the fuzzy differential equation in the form of differential inclusions is transformed into the governing equation of the membership degree and the membership distribution of the fuzzy solution is composed of the membership degrees solved from the governing equation. In the procedure, no comparison or data storage is required, which makes the method have high computational efficiency and low memory cost. Since the governing equation of the membership degree is derived from the master equation of fuzzy dynamics, the method is validated by our theoretically proving the equivalence of the solution of the fuzzy differential equation via differential inclusions and that of the fuzzy master equation. Furthermore, the new method is verified by our comparing the numerical solution with the analytical solution in two examples. Finally, with use of the method, the response solutions are obtained for the Mathieu system and the rotor/stator contact system with fuzzy uncertainties. [ABSTRACT FROM AUTHOR]

Potassium (K) and calcium (Ca) K‐edge X‐ray adsorption near‐edge (XANES) spectroscopy were performed on thirty‐three chemical compounds and geological materials, including chemical reagents, organometallic compounds, silicates, carbonates and igneous rock reference materials. The results confirm that the fine structure of the K‐edges for specimens is unique and distinguishable. The results suggest that compositional and local atomic variations strongly regulate spectral characteristics. Acquired XANES spectra with the library of distinctive spectral features of model references approve the fingerprint identification of different phases of K and Ca involved in geological materials. Moreover, this reveals that typical compositional changes in geological samples could strongly affect spectral features. As an example, we quantitatively determined the silicate species of K and Ca in two igneous rock reference materials by linear combination fitting. The dominant hosts and molecular environments of K and Ca can be interpreted based on pre‐edge/post‐edge peak position, intensity, shifts and resonance features, thus improving the understanding of the (bio)geochemical cycling, partitioning and isotopic fractionation of K and Ca. The outcomes serve as a complementary database for a vast number of scientific contexts, including aspects of geological and environment sciences. [ABSTRACT FROM AUTHOR]

Understanding the influence of terrestrial soil-atmosphere-biosphere exchanges on Li geochemical behaviors is vital before using Li isotopes as a weathering tracer. We investigated Li geochemistry of the humid and arid regolith profiles formed on the Pololu lavas, the Kohala Mountain, Hawaii. The shallow regolith (0–1 m depth) retains Li (τ Li,Nb > 0) and displays peak Li accumulation in biologically-active, near-surface soil layers (humid, τ Li,Nb = 10.9; arid, τ Li,Nb = 2.8), with heavy Li isotopic compositions (humid, 4.7–9.9‰; arid, 4.0–13.9‰) with respect to the basalt signal (2.2‰). The deep regolith (>1 m) demonstrates δ7Li (ave. 3.3‰) comparable to the composition of the underlying parent basalt (2.2‰). Decoupling of Li abundance and isotopic composition in the shallow regolith from those of the deep regolith implies different regolith controls on Li chemistry at vertical locations. The Li geochemistry in the shallow regolith has been substantially influenced by: (i) atmospheric deposition, (ii) plant cycling, and (iii) secondary mineral formation. In addition to weathering alteration, our data show that dust addition mainly influences δ7Li in the humid regolith, and marine aerosol largely affects δ7Li in the arid regolith. In the humid regolith, downward seepage migration allows for deeper and more advanced weathering, whereas occasional wetting events followed by rapid drying likely dominate in the arid regolith. Thus, biological cycling and the deposition of Asian dust and volcanic ash from the more recent Hawi eruptions are responsible for upward Li enrichment in soils and increases of soil δ7Li composition in the shallow regolith. This is particularly important in the humid site with dense plant coverage and heavy rainfall. By contrast, the deep regolith of the humid and arid sites is mostly affected by pore fluid percolation and accumulation, thus inheriting heavy Li isotope signals from pore fluids. Our study emphasizes climate-regulated and long-neglected biological controls on terrestrial Li cycling during chemical weathering. [ABSTRACT FROM AUTHOR]

The feedback between CO 2 sources and sinks through chemical weathering is one of the important reasons why Earth has maintained a habitable climate for over four billion years. The lithium (Li) isotopic system is a promising tracer of silicate weathering, but the mechanisms causing its isotope fractionation during weathering remain ambiguous. Here, we performed batch experiments of Li adsorption to one of the common clay minerals -kaolinite in three sets, including the time-series, pH-dependent, and concentration-control sets. Our results demonstrate that the liquid-solid Li isotope fractionation reaches up to 36‰, with up to 99% initial Li being adsorbed on kaolinite. The magnitudes of Li adsorption and isotope fractionation increase with reaction time, and reach the steady-state after ∼1000 min. The magnitude of Li isotope fractionation increases with the adsorption ratio of Li, in positive relationships with solute pH and ionic strength. At constant solute pH = 8.5 and ionic strength of 0.001 M, the adsorption ratio and isotope fractionation of Li on kaolinite reach the maximum with the lowest initial Li concentration of 2 μM. In experiments, Li is removed by kaolinite as the inner-sphere and/or outer-sphere complexes, likely followed by structural occupation as supported by incomplete desorption. We model the Li isotope fractionation in all three sets, which can be best described by Rayleigh distillation models. In summary, significant Li isotope fractionation occurs following a kinetic law in closed-systems during adsorption on kaolinite. Adsorption-driven isotope fractionation conforms to a kinetic solid-liquid isotope fractionation factor α ∼ 0.992, consistent with theoretical ion-desolvation between complexed and dissolved ions (α = 0.9925, Hofmann et al., 2012). This study reveals a vital kinetic role of clay uptake in Li isotope fractionation during chemical weathering, suggesting rapid forward adsorption reaction versus relatively slow backward reaction. The dominance of the kinetic mechanism over the equilibrium mechanism further explains field observations from rivers worldwide. Given above, the outcome of this study calls for additional attention on low-temperature kinetic Li isotope fractionation at Earth's surface and further refinement of quantitative models using geological Li records to trace weathering and reconstruct climate. [ABSTRACT FROM AUTHOR]

We report [Li] and δ7Li values for a well-characterized suite of 52 geographically (165–184°W), compositionally (SiO 2 = 46–70 wt.%), and temporally (0–38 Ma) diverse lavas and intrusive samples. The δ7Li in these rocks range from −0.7‰ to +14.2‰, with 32 of the 35 lavas and 12 of the 17 intrusive samples falling within the depleted mantle range (δ7Li +1.6 to +5.6‰), as sampled by mid-ocean ridge basalts (MORB). The δ7Li values of Aleutian lavas do not exhibit the spatial trends observed in other slab component tracers, nor do δ7Li values correlate with any slab component indicators, such as radiogenic isotopes, oxygen isotopes, or trace element ratios such as Cs/La and Th/La. The δ7Li values in Aleutian intrusions also do not exhibit temporal trends, however, an overall positive relationship exists between δ7Li and Th/Nd. Mixing models for δ7Li and 143Nd/144Nd values suggest that Aleutian samples within or above the MORB δ7Li range can be explained by addition of <1–2% sediment-derived aqueous fluid and ≤3% sediment melt to depleted mantle; both are required to explain the range in δ7Li that is observed. Sediment-derived fluid exerts a stronger control on Aleutian samples having higher δ7Li values than the MORB range, while sediment melt skews the Li isotopic compositions of MORB-range samples to slightly lower values than if sediment fluid was the only slab influence. Our study demonstrates that a slab signature may be deciphered via modeling even in arcs where spatial trends in δ7Li values and correlations with slab component indicators are lacking. [ABSTRACT FROM AUTHOR]

Aiming at the occlusion problem in the current video multi-target tracking process, a multi-target detection and tracking algorithm combining YOLO v3 is proposed. The framework based on detection tracking is selected as the overall framework for tracking, and YOLO v3 is used to detect the target information. Based on the selected detection category, the proposed tracking algorithm is used to complete the multi-target tracking of this category through data association. Aiming at the problems of target occlusion in the tracking process and abnormal trajectory tracking caused by target occlusion, a correction algorithm is proposed. Most of the occluded targets in the test video can be accurately tracked in the experiment, but some target identity swaps will occur when the background moves. The proposed algorithm has certain accuracy and real-time performance in solving the occlusion problem in multi-target tracking. [ABSTRACT FROM AUTHOR]

In this paper, the Fuzzy Generalized Cell Mapping (FGCM) method is developed with the help of the Adaptive Interpolation (AI) in the space of fuzzy parameters. The adaptive interpolation on the set-valued fuzzy parameter is introduced in computing the one-step transition membership matrix to enhance the efficiency of the FGCM. For each of initial points in the state space, a coarse database is constructed at first, and then interpolation nodes are inserted into the database iteratively each time errors are examined with the explicit formula of interpolation error until the maximal errors are just under the error bound. With such an adaptively expanded database on hand, interpolating calculations assure the required accuracy with maximum efficiency gains. The new method is termed as Fuzzy Generalized Cell Mapping with Adaptive Interpolation (FGCM with AI), and is used to investigate codimension-two bifurcations in two-dimensional and three-dimensional nonlinear dynamical systems with fuzzy noise. It is found that global changes in fuzzy dynamics are dominated by the underlying deterministic counterparts, and the fuzzy attractor expands along the unstable manifold leading to a collision with a saddle when a bifurcation occurs. The examples show that the FGCM with AI has a thirtyfold to fiftyfold efficiency over the traditional FGCM to achieve the same analyzing accuracy. [ABSTRACT FROM AUTHOR]

This study develops and optimizes a new protocol to measure lithium isotope ratios using a single collector quadrupole inductively coupled plasma mass spectrometer (Q-ICP-MS) operated under hot plasma (1550 W) conditions with a sample–standard bracketing method. Our Q-ICP-MS method reduces sample consumption to 2.5 ng of Li and achieves a high long-term precision of 1.1‰ (2SD). This Q-ICP-MS method exhibits high matrix tolerance (Na/Li < 100), suitable for ng-sized and high-matrix geological samples. We also developed a dual-column system for Li separation, with large loading capacity (29.6 meq), complete recovery (∼100%) and satisfactory purification (Na/Li m m−1 < 1), as well as a fixed elution range for Li fractions (28–60 mL). This new chromatography method has been applied to chemically diverse materials, producing consistent results. In addition, we report the Li isotope compositions of 13 geostandards, and our measurements agree well with reported data within analytical uncertainties. This study documents that Li element concentration and Li isotope composition can be routinely measured using a single collector ICP-MS, which is convenient and commercially affordable for future Li isotope research across the fields of Earth and Environmental Sciences. [ABSTRACT FROM AUTHOR]

The lithium isotope system can be an important tracer for various geological processes, especially tracing continental weathering. The key to this application is the accurate and precise determination of lithium isotopic composition. However, some of the previously established column separation methods are not well behaved when applied to chemically diverse materials, due to the significant variations in matrix/lithium ratios in some materials. Here, we report a new dual‐column system for lithium purification to achieve accurate and precise analysis of lithium isotopic compositions using a multi‐collector inductively coupled plasma‐mass spectrometer (MC‐ICP‐MS). Compared with single‐column systems, our dual‐column system yielded a consistent elution range of the lithium‐bearing fraction (7–16 ml) for samples with a large range of lithium loads and matrix compositions, so that column re‐calibration is not required. In addition, this method achieved complete lithium recovery and low matrix interference (e.g., Na/Li ≤ 1) with a short elution time (~ 6 h, excluding evaporation), with the entire procedure completed in 1.5 days. We report high precision Li isotopic compositions in twelve chemically diverse materials including seawater, silicates, carbonates, manganese nodules and clays. New recommended Li isotopic values and associated uncertainties are presented as reference values for quality control and inter‐laboratory calibration for future research and were consistent with previously published data. However, significant lithium isotopic variances (~ 1‰) in BHVO‐2 from different batches suggest Li isotopic heterogeneity in this reference material and that Li isotopic studies using this reference material should be treated with caution. [ABSTRACT FROM AUTHOR]

Abstract Inferring redox conditions for ancient marine environments is critical to our understanding of biogeochemical cycles over Earth history. Because of the redox sensitivity of cerium (Ce) relative to other rare earth elements (REEs) and its uptake in marine carbonates, the Ce anomaly (Ce/Ce*) is widely applied to ancient carbonates as a proxy for local redox conditions in the water column. However, carbonate sediments and rocks are particularly vulnerable to multiple stages and styles of post-depositional diagenetic alteration where the diagenetic redox conditions and fluid compositions can vary widely from overlying seawater. Evaluations of the effects of this post-depositional alteration for the Ce anomaly have mostly been limited to ancient carbonate rocks rather than recent, well-characterized analog facies. Here, we report on analyses of REE plus yttrium concentrations (REY) and Ce anomalies in bulk carbonate samples from drill cores collected in the Bahamas (Clino and Unda) that allow us to track loss or retention of primary signals of initial oxic deposition through a range of subsequent alteration scenarios mostly under anoxic conditions. Specifically, these materials have experienced well-constrained overprints linked to meteoric processes and marine burial diagenesis, including dolomitization. Our results show that, regardless of mineralogy, diagenetic fluid composition, and redox state, the REY patterns in these carbonates, including the Ce anomaly, are similar to those of modern oxic seawater, indicating that they likely record the seawater signatures of primary deposition. As such, the Ce anomaly in shallow marine carbonates has the potential to preserve records of primary deposition even when subject to multiple stages and styles of diagenetic alteration, confirming its utility in studies of ancient marine redox. [ABSTRACT FROM AUTHOR]

Abstract In this letter, a Wada boundary bifurcation (WBB) induced by a boundary saddle touching another boundary saddle is first found through the study of a forced damped pendulum. The WBB can be quantitatively described by the change both in the number of basins involved and in the geometrical size of the boundary. We perceive the manifold structures of the two saddles, that is, a pre-existence of heteroclinic crossing and the other nearly forming heteroclinic tangency exist before the WBB. So we schematically construct the equivalent topological structure of the manifolds of arbitrary two saddles, and rigorously prove two theorems that indicate the existence of the heteroclinic tangency and thus generically confirm the mechanism of such WBB. Highlights • Wada Boundary Bifurcation is caused by a collision between two boundary saddles. • The bifurcation changes both the size and the domicile number of basin boundaries. • The mechanism is concluded from the topology of the manifolds of the saddles. • The mechanism is rigorously proved to be generic in nonlinear dynamical systems. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Glutaminase-1 (GLS1) is a mitochondrial enzyme found in endothelial cells (ECs) that metabolizes glutamine to glutamate and ammonia. Although glutaminolysis modulates the function of human umbilical vein ECs, it is not known whether these findings extend to human ECs beyond the fetal circulation. Furthermore, the molecular mechanism by which GLS1 regulates EC function is not defined. In this study, we show that the absence of glutamine in the culture media or the inhibition of GLS1 activity or expression blocked the proliferation and migration of ECs derived from the human umbilical vein, the human aorta, and the human microvasculature. GLS1 inhibition arrested ECs in the G 0 /G 1 phase of the cell cycle and this was associated with a significant decline in cyclin A expression. Restoration of cyclin A expression via adenoviral-mediated gene transfer improved the proliferative, but not the migratory, response of GLS1-inhibited ECs. Glutamine deprivation or GLS1 inhibition also stimulated the production of reactive oxygen species and this was associated with a marked decline in heme oxygenase-1 (HO-1) expression. GLS1 inhibition also sensitized ECs to the cytotoxic effect of hydrogen peroxide and this was prevented by the overexpression of HO-1. In conclusion, the metabolism of glutamine by GLS1 promotes human EC proliferation, migration, and survival irrespective of the vascular source. While cyclin A contributes to the proliferative action of GLS1, HO-1 mediates its pro-survival effect. These results identify GLS1 as a promising therapeutic target in treating diseases associated with aberrant EC proliferation, migration, and viability. [ABSTRACT FROM AUTHOR]

Past variations in lithium concentration and isotope ratio of seawater recorded in marine carbonates have shown great potential in tracing carbon cycles during critical climate transitions, especially coupled with the radiogenic strontium isotope system. However, acquiring reliable seawater Li isotope compositions from marine carbonates can be technically challenging because non‑carbonate phases co-existed in ancient marine carbonates can easily contaminate carbonate Li signal during inappropriate sample dissolution. Each contaminant phase, including Mn oxides, clays, and silicate minerals, can have different Li isotope compositions than that preserved in the carbonate lattice. More importantly, a significant portion of Li is adsorbed on the Mn oxides and clay minerals. This fraction is considered exchangeable and can be liberated using weak acid without destruction of mineral structure. Cleaning procedures and partial digestion have been applied to remove the exchangeable Li fraction in contaminative phases and selectively dissolve the carbonates. However, previous methods cannot be directly applied to ancient marine carbonates of various carbonate purity, which lack systematic testing on the threshold of sample purity to maintain the efficiency of the precleaning and partial digestion. Here we report an efficient sequential leaching protocol to extract primary seawater Li and Sr isotope compositions from bulk marine carbonates. The procedure consists of pre-cleaning steps using 1 M ammonium acetate and 1 M ammonium carbonate to completely remove the exchangeable fraction, followed by partial digestion using 0.3 M acetic acid to selectively target carbonate-bounded Li. We validate this method by mixing carbonate and contaminant endmembers in different weight percentages. We found this protocol works effectively for carbonates of >80% purity. Additionally, we demonstrate filtration is necessary when separating leachates from the solids to quantitatively avoid contaminations from non‑carbonate phases. We also suggest NIST-SRM-1d to be a cross-lab carbonate standard for Li isotope analyses and report its long-term external precision (two years). To sum, we propose an effective community standard procedure to reconstruct δ7Li sw records using ancient bulk carbonate samples. [Display omitted] [ABSTRACT FROM AUTHOR]

Rare earth elements (REEs) signatures in the dissolved loads of rivers serve as excellent monitors of weathering processes within a basin. However, quantifying REE behavior spatially (along a river's profile) and temporally (seasonable variations) is rare. This investigation reports REE concentrations of dissolved river loads collected during four sampling seasons at five monitoring stations along the Neuse River, North Carolina. The areal percentage of the Neuse River's catchment lithology composition, Post Archean Australian Shale (PAAS) normalized REE patterns, inter-REE ratios, and calculated anomalous REE values (i.e. cerium anomaly, gadolinium anomaly) were determined at each site in four seasons over a year. Our results show slight differences among inter-REE relationships and anomalous REE values in the dissolved loads along the length of the river. PAAS normalized REE patterns of dissolved water loads vary slightly spatially and temporally among the five sampling stations, and experience varying values of anomalous REE values. Collected data indicates that both variations in localized REE patterns and local bedrock occur along the river profile. Significant gadolinium (Gd) anomalies varied seasonally and spatially at select sites, suggesting changes in REE behavior along a river result from both natural and anthropogenic processes. [ABSTRACT FROM AUTHOR]

This study investigated the temporal activation of arginase in obese Zucker rats (ZR) and determined if arginase inhibition prevents the development of hypertension and improves insulin resistance in these animals. Arginase activity, plasma arginine and nitric oxide (NO) concentration, blood pressure, and insulin resistance were measured in lean and obese animals. There was a chronological increase in vascular and plasma arginase activity in obese ZR beginning at 8 weeks of age. The increase in arginase activity in obese animals was associated with a decrease in insulin sensitivity and circulating levels of arginine and NO. The rise in arginase activity also preceded the increase in blood pressure in obese ZR detected at 12 weeks of age. Chronic treatment of 8-week-old obese animals with an arginase inhibitor or l-arginine for 4 weeks prevented the development of hypertension and improved plasma concentrations of arginine and NO. Arginase inhibition also improved insulin sensitivity in obese ZR while l-arginine supplementation had no effect. In conclusion, arginase inhibition prevents the development of hypertension and improves insulin sensitivity while l-arginine administration only mitigates hypertension in obese animals. Arginase represents a promising therapeutic target in ameliorating obesity-associated vascular and metabolic dysfunction. [ABSTRACT FROM AUTHOR]

In this paper, a new method of Generalized Cell Mapping with Sampling-Adaptive Interpolation (GCMSAI) is presented in order to enhance the efficiency of the computation of one-step probability transition matrix of the Generalized Cell Mapping method (GCM). Integrations with one mapping step are replaced by sampling-adaptive interpolations of third order. An explicit formula of interpolation error is derived for a sampling-adaptive control to switch on integrations for the accuracy of computations with GCMSAI. By applying the proposed method to a two-dimensional forced damped pendulum system, global bifurcations are investigated with observations of boundary metamorphoses including full to partial and partial to partial as well as the birth of fully Wada boundary. Moreover GCMSAI requires a computational time of one thirtieth up to one fiftieth compared to that of the previous GCM. [ABSTRACT FROM AUTHOR]

Different types of neuronal nicotinic acetylcholine receptors (nAChRs) are expected to occur in vivo, most structure-activity relationship studies have been carried out for just a few neuronal subtypes. The present review enlightens current aspects of venom modulators of nAChRs. Important electronic databases such as PubMed or Google scholar were explored for the collection of latest studies in the field. Clinical and basic research has shown that cholinergic receptors play a role in several disorders of the nervous system such as chronic pain, Alzheimer's disease and addiction to nicotine, alcohol and drugs. Unfortunately, the lack of selective modulators for each subtype of nAChR makes their pharmacological characterization difficult, which has slowed the development of therapeutic nAChR modulators with high selectivity and absence of off-target side-effects. Animal venoms have proven to be an excellent natural source of bioactive molecules with activity against ion channels. The present review concludes that the presence of small-molecule nAChR modulators in spider venoms support the use of venoms as a potential source of novel modulators. [ABSTRACT FROM AUTHOR]

Coral skeletal P/Ca ratio has been developed as an indicator of temporal seawater dissolved inorganic phosphorus (DIP). The use of coral P/Ca proxy helps to assess oceanographic and climatic impacts such as upwelling, circulation, and continent runoffs on marine biogeochemical cycles. However, factors controlling skeletal P incorporation and elemental partitioning between seawater and coral skeletons remain elusive. We conducted temperature-controlled (∼21 to 29 °C) aquaria culture experiments using two colonies of Porites australiensis corals (here refer to B and C) with the only difference in zooxanthellae density (B > C). The coral growth rate ranges from 9.4 to 19.4 mg/day (B) and 0.7 to 14.1 mg/day (C). Only the growth rate of colony C significantly correlates to temperature, potentially reflecting physiological controls on the two colonies given the difference in the zooxanthellae density. We measured coral P/Ca ratios by Inductively coupled plasma mass spectrometry and determined skeletal P speciation through a synchrotron-based spectroscopic approach. Coral P/Ca ratio ranges from 6.5 to 18.6 μmol/mol (B) and 7.2 to 19.8 μmol/mol (C). The dominance of organic-P is confirmed, and the presence of inorganic-P cannot be excluded. Only colony C has a strong P/Ca dependence on temperature and both colonies show strong correlations between P/Ca and growth rate. Although growth rate and temperature are intercorrelated, the growth rate is more likely the direct controlling factor on coral P/Ca in our experiments. Combined laboratory data with field observations, we suggest that the validity of the Porites P/Ca proxy may be influenced by seawater DIP, coral species, and growth rate. • Cultured coral P/Ca ratio can be variable with relatively constant seawater chemistry. • Organic phosphorus is widely present in coral skeletons despite oxidative cleaning. • The validity of the P/Ca proxy could be influenced by seawater DIP, coral species, and growth rate. [ABSTRACT FROM AUTHOR]

Background Outcomes of coiling embolization versus clipping for patients with high-grade aneurysmal subarachnoid hemorrhage (aSAH) have not been previously compared. We reviewed current evidence regarding the safety and efficacy of clipping versus coiling for high-grade aSAH. Methods We conducted a meta-analysis of studies that compared clipping with coiling in patients with high-grade aSAH published from January 1999 to February 2016 in Medline, Embase, and Cochrane databases based on PRISMA inclusion and exclusion criteria. Binary outcome comparisons between clipping and coiling were described using odds ratios (ORs). Results Three randomized controlled trials (RCTs) and 16 observational studies were included. There was no statistical difference in good outcome rates between the clipping and coiling groups (OR, 1.44; 95% confidence interval [CI], 0.97–2.13). Subgroup analysis showed no significant difference between the 2 treatments in non-RCTs (OR, 1.49; 95% CI, 0.95–2.36) and RCTs (OR, 1.15; 95% CI, 0.59–2.25). Coiling was associated with higher mortality (OR, 0.55; 95% CI, 0.41–0.75). Lower mortality was associated with clipping in non-RCTs (OR, 0.54; 95% CI, 0.40–0.74), but there was no difference in the RCTs (OR, 0.79; 95% CI, 0.19–3.39). Coiling was not associated with lower rates of complications including rebleeding (OR, 0.62; 95% CI, 0.30–1.29), ischemic infarct (OR, 0.89; 95% CI, 0.53–1.49), symptomatic vasospasm (OR, 0.76; 95% CI, 0.45–1.29), or shunt-dependent hydrocephalus (OR, 1.33; 95% CI, 0.52–3.40). Conclusion The outcome with coiling is not superior to clipping in patients with high-grade aSAH; moreover, coiling has a greater risk of mortality. [ABSTRACT FROM AUTHOR]

Although endothelial cells produce substantial quantities of ammonia during cell metabolism, the physiologic role of this gas in these cells is not known. In this study, we investigated if ammonia regulates the expression of heme oxygenase-1 (HO-1), and if this enzyme influences the biological actions of ammonia on endothelial cells. Exogenously administered ammonia, given as ammonium chloride or ammonium hydroxide, or endogenously generated ammonia stimulated HO-1 protein expression in cultured human and murine endothelial cells. Dietary supplementation of ammonia also induced HO-1 protein expression in murine arteries. The increase in HO-1 protein by ammonia in endothelial cells was first detected 4 h after ammonia exposure and was associated with the induction of HO-1 mRNA, enhanced production of reactive oxygen species (ROS), and increased expression and activity of NF-E2-related factor-2 (Nrf2). Ammonia also activated the HO-1 promoter and this was blocked by mutating the antioxidant responsive element or by overexpressing dominant-negative Nrf2. The induction of HO-1 expression by ammonia was dependent on ROS formation and prevented by N-acetylcysteine or rotenone. Finally, prior treatment of endothelial cells with ammonia inhibited tumor necrosis factor-α-stimulated cell death. However, silencing HO-1 expression abrogated the protective action of ammonia and this was reversed by the administration of carbon monoxide but not bilirubin or iron. In conclusion, this study demonstrates that ammonia stimulates the expression of HO-1 in endothelial cells via the ROS-Nrf2 pathway, and that the induction of HO-1 contributes to the cytoprotective action of ammonia by generating carbon monoxide. Moreover, it identifies ammonia as a potentially important signaling gas in the vasculature that promotes endothelial cell survival. [ABSTRACT FROM AUTHOR]

We measured the Ce concentration, oxidation state, and isotope composition of bauxites developed on the Columbia River Basalts (CRBs) to evaluate the impacts of redox and non-redox processes on the Ce isotopic variability on Earth's surface. Bauxites recovered from drill cores show upward increasing Ce concentration (5.4–88.7 μg/g) and overall depletion of Ce (mass transfer coefficient, τ Ce , Nb : -0.96 to -0.52, i.e., net depletion of 52-96% relative to their parent CRBs). There is a wide range of the Ce anomaly (Ce/Ce⁎) from 0.4 to 6.3 and 0.6 to 1.4 in the Cowlitz and Columbia bauxites, respectively. The most positive Ce anomalies appear at the shallow regolith (2-5 m depth). Cerium primarily presents in its trivalent form in deposited exogenous materials (wind-blown dust from an old, weathered region of the continent) and primary CRBs. There is a downward increase in the fraction of Ce (IV) in the regolith. Bauxite δ 142 Ce ranges from -0.161±0.034 to -0.018±0.043‰ and -0.277±0.034 to -0.046±0.034‰ in the Cowlitz and Columbia profiles, respectively. The Ce isotope record reflects the redox cycle of Ce and Mn and is masked by dust accretion on the top. The enrichment of Ce (IV) occurs in the transition zone (the bottom of the shallow regolith) with minor Ce isotope shifts from the CRBs (δ 142 Ce from -0.080±0.034 to -0.04±0.034‰) likely caused by minor isotopic fractionation linked to O 2 -driven CeO 2 precipitation. There are negative Ce isotope shifts from the basaltic parents and the enrichment of oxidized Ce and Mn in the deep regolith (5-9 m depth), where large isotopic fractionation probably induced by Ce oxidative adsorption on MnO 2 plays a vital role. The vertical difference between Ce/Ce⁎ and δ 142 Ce may be attributed to the climatic oxidation-reduction cycle of Mn and Ce, leaving discrete CeO 2 grains in the shallow regolith while transferring isotopically light Ce associated to oxidized Mn deposits down to the deep regolith. We conclude that a combination of Ce species isotopes and anomalies potentially records terrestrial redox status and fluctuation. • An investigation of Ce speciation, isotope composition and anomaly in bauxite cores. • Different responses of terrestrial δ 142 Ce signals to the presence of various Ce species. • Contrasting responses of terrestrial Ce/Ce⁎ and δ 142 Ce signals to the Ce redox cycle. [ABSTRACT FROM AUTHOR]

• We evaluate seawater K uptake via early diagenesis using modern marine sediments. • Continental weathering and reverse weathering mainly control sediment δ 41 K values. • Glauconite is an important sink of seawater K with preference to isotopically lighter K. The sedimentary fluxes controlling potassium (K) budget of the oceans and the isotope composition of K (δ 41 K) potentially yield valuable information about the global K cycling. However, at present sedimentary diagenesis in the oceans is one of the least well-known components of the seawater K budget. This study presents a dataset of the modern (<50 cm) sediments from a range of hydrographic regimes including continental margin settings (the Peru Margin, California Borderland, and Mexican Margin) and deep-sea environments (the Equatorial Pacific). We determine the K isotope compositions and origins of K in the sediments and compare them with the results of elemental abundances and spectroscopic analyses. The wide variability in sedimentary K/Al and Rb/K ratios, K-phase distributions, and K isotope compositions support the interplay between continental weathering, which provides clastic inputs, and sedimentary diagenesis, which constitutes an important sink of seawater K. The net result of these processes potentially alters the K elemental and isotopic budgets in sediment strata of various marine environments. We demonstrate that K is dominantly hosted by illite, glauconite, and feldspars, and regional K-phase partitioning modulates marine sedimentary K budget. For example, considerable amounts of K hosted in illite (up to 90%) primarily of terrestrial origins increase Rb/K ratios, producing low δ 41 K in California Borderland sediments (−0.57 to −0.40‰), the Pescadero Slope from the Mexican Margin (−0.42 to −0.39‰), and Equatorial Pacific deep-sea basins (−0.56 to −0.44‰). In contrast, glauconite authigenesis causes decreases in the Rb/K ratio and relatively high δ 41 K at a site along the Peru Margin (−0.35 to −0.29‰), as well as at two other sites along the Mexican Margin (−0.39 to −0.27‰). Despite the presence of feldspar-K (<20%), δ 41 K in the sediments reflects dominant contributions of detrital illite (δ 41 K illite ∼ −0.56‰) and authigenic glauconite (δ 41 K glauconite ∼ −0.18‰). We conclude that the formation of glauconite in the sediments takes up isotopically light K from seawater and serves as an important sink of seawater K (including K in seawater-derived porewater) (∼1 to 16, average ∼6 Tg K⋅yr−1) during early diagenesis, especially on continental margins. [ABSTRACT FROM AUTHOR]

The use of HIV protease inhibitors (PIs) has extended the duration and quality of life for HIV-positive individuals. However there is increasing concern that this antiviral therapy may promote premature cardiovascular disease by impairing endothelial cell (EC) function. In the present study, we investigated the effect of HIV PIs on EC function and determined if the enzyme heme oxygenase (HO-1) influences the biological action of these drugs. We found that three distinct PIs, including ritonavir, atazanavir, and lopinavir, stimulated the expression of HO-1 protein and mRNA. The induction of HO-1 was associated with an increase in NF-E2-related factor-2 (Nrf2) activity and reactive oxygen species (ROS). PIs also stimulated HO-1 promoter activity and this was prevented by mutating the antioxidant responsive element or by overexpressing dominant-negative Nrf2. In addition, the PI-mediated induction of HO-1 was abolished by N-acetyl- l -cysteine and rotenone. Furthermore, PIs blocked EC proliferation and migration and stimulated the expression of intercellular adhesion molecule-1 and the adhesion of monocytes on ECs. Inhibition of HO-1 activity or expression potentiated the anti-proliferative and inflammatory actions of PIs which was reversed by bilirubin but not carbon monoxide. Alternatively, adenovirus-mediated overexpression of HO-1 attenuated the growth-inhibitory and inflammatory effect of PIs. In contrast, blocking HO-1 activity failed to modify the anti-migratory effect of the PIs. Thus, induction of HO-1 via the ROS–Nrf2 pathway in human ECs counteracts the anti-proliferative and inflammatory actions of PIs by generating bilirubin. Therapeutic approaches targeting HO-1 may provide a novel approach in preventing EC dysfunction and vascular disease in HIV-infected patients undergoing antiretroviral therapy. [ABSTRACT FROM AUTHOR]

Lysimachia christinae Hance (Christina loosestrife), a mat-forming perennial herb from the Primulaceae family, is a famous Chinese medicinal material and excellent ground cover plant for landscaping. The natural triploid of L. christinae is reported here so as to provide new reference for the development and utilization of L. christinae. In this study, L. christinae plants introduced from Lion Mountain population in Wuhan and Moon Mountain population in Huangshi were cultivated in the same text site. And then the plant morphology and the stoma size were observed. The chromosome numbers and karyotypes were investigated by the conventional pressing plate method. The results showed that the leaf length, leaf width, leaf area, length of petal, petal width, petal area and leaf stoma area of L. christinae from Moon Mountain population in Huangshi were significantly higher than those of L. christinae from Lion Mountain population in Wuhan. In addition, the karyotype formula of L. christinae from Moon Mountain population in Huangshi was 3n=36=3m+3sm+6st+24t, which was different with that of L. christinae from Lion Mountain population in Wuhan (2n=24=2m+2sm+4st+16t). Therefore, in this paper, the L. christinae from Moon Mountain population in Huangshi was identified as natural triploid based on abovementioned morphology and chromosome datum. The discovery of natural triploid in L. christinae enriched the polyploidy data of L. christinae. It would not only provide reference for research on genetic diversity and evolution of L. christinae, but also supply the excellent material for medicine, landscaping and breeding. [ABSTRACT FROM AUTHOR]

The breakdown phenomenon at freeway has both practical and theoretical interests. Many researchers have done great efforts on it. As a result, the stochastic concept for freeway capacity was defined and some approaches were developed. However, due to the fact that it is impossible to observe the value of the capacity, it is difficult to obtain the exact traffic capacity distribution. In this paper, traffic operational degradation concept was introduced and degradation model was developed to describe traffic breakdown process. A stochastic degradation parameter is introduced to explain the phenomena of traffic breakdown occurring at various flow rate levels. Traffic breakdown probability and traffic capacity distribution were derived theoretically. Based on the surveyed data, the experimental model was obtained by using the bootstrap method. The results indicate that Weibull distribution function can be used to describe traffic capacity stochastic nature. [ABSTRACT FROM AUTHOR]

We evaluate the factors influencing the abundance, [Li], and isotopic composition of riverine Li delivered to the oceans through analyses and modeling of [Li] and δ 7 Li in streams and groundwaters draining a single continental lithology, the Columbia River Basalts (CRBs). The streams were sampled in different climate zones that lie east (dry), and west (wet) of the Cascades Mountains, and during two different seasons (summer and late winter) in order to evaluate climatic and seasonal influences on Li isotopes in rivers. Dissolved Li ( δ Li dis 7 = + 9.3 to +30.4) is systematically heavier than that of fresh or weathered CRBs (−4.7 to +6.0, Liu et al., 2013 ), suspended loads (−5.9 to −0.3), and shallow groundwaters (+6.7 to +9.4), consistent with previous studies showing that Li isotope fractionation is affected by equilibration between stream water and secondary minerals. However, the lack of correlation between δ 7 Li dis and climate zone, the uniform secondary minerals and bedrock, coupled with the highly variable ( > 20 ‰ ) δ Li dis 7 indicate that other factors exert a strong control on δ 7 Li dis . In particular, the heavier Li in streams compared to the shallow groundwaters that feed them indicates that continued isotopic fractionation between stream water and suspended and/or bed loads has a major influence on riverine δ 7 Li. Seasonal δ 7 Li variation is observed only for streams west of the Cascades, where the difference in precipitation rate between the dry and wet seasons is greatest. Reactive transport model simulations reveal that riverine δ 7 Li is strongly controlled by subsurface residence times and the Li isotope fractionation occurring within rivers. The latter explains why there is no positive correlation between δ 7 Li and traditional weathering proxies such as Si or normalized Si in rivers, as riverine Li isotope fractionation drives δ 7 Li to higher values during transport, whereas the concentrations of major cations and anions are diluted. The varying residence time for groundwaters feeding the western streams in summer (long residence times, higher δ 7 Li, greater weathering) and winter (short residence times, lower δ 7 Li, less weathering) explains the observed seasonal variations. A global, negative correlation between δ 7 Li and Li/Na for streams and rivers draining basaltic catchments reflects the overall transport time, hence the amount of silicate weathering. Based on our results, the increase of δ 7 Li in seawater during the Cenozoic is unlikely related to changing climate, but may reflect mountain building giving rise to increased silicate weathering. [ABSTRACT FROM AUTHOR]

When the faults in energy-storage capacitor in flameproof switchgears are diagnosed with single evidence, the diagnostic system has a higher misdiagnosis. To overcome this problem, this paper proposes a capacitor failure diagnosis method based on information fusion theory. Firstly, through analyzing the failure mechanism of storage-capacitor, the feature parameters of capacitor were extracted, and the evidence source for state assessment was then obtained. Secondly, the basic probability assignment for capacitor state was determined according to fuzzy membership functions to avoid the subjectivity of membership assigned with expert experiences, and the membership function parameters were established by a minimum fuzzy optimization model. Finally, the different evidences were integrated by D-S combination rule, and according to BPA decision rule, the condition of the energy storage capacitor in practical operation can be assessed. By using the method proposed and the operation data, the current state of the energy-storage capacitors were obtained, and the evaluation study results demonstrate its effectiveness. [ABSTRACT FROM AUTHOR]

Aerospace vehicle design is an important component of cross-department subject in BUAA. Experimental teaching is the key process to improve students'innovation ability and quality of practice. Aiming at the particularity of aerospace vehicle design major and the problems of present practical teaching, such as lack of professional experimental instruments, experimental teaching limitation by the space and cost, the contents of experiment breaking away from engineering practice, this paper explores and summarizes practical teaching reform in accordance with years of teaching experience. Four available strategies including experimental equipment miniaturization, practical training serialization, practical contents scientification and outstanding training works inheritance, are proposed. According to the experimental teaching result of these years, the limitation of space and fund and lack of experimental instruments are solved. Manpower and material resources are reasonably dispatched and comprehensively utilized. The students ' scope of knowledge is broadens and the classroom teaching is enriched. Good teaching practice effect is obtained and it may be helpful to industry members and similar mor teachers. [ABSTRACT FROM AUTHOR]

• Large variations in coral K phase and isotope composition depending on temperature. • Corals show both higher and lower δ 41 K values compared to the seawater δ 41 K value. • Increasing temperature causes increases in organic-K but decreases in carbonate-K contribution. • The isotopic composition in coral skeletons corresponds to skeletal K phase partitioning. Potassium (K) participates in coral biological activities and accumulates in their skeletons, driving the fractionation of stable K isotopes (41K/39K). Constraining the influences of biotic and abiotic controls on K isotope fractionation is important for interpreting coral records. However, the processes and mechanisms regulating K incorporation into coral skeletons and K isotope fractionation between seawater and coral skeletons remain unknown. Here, we combined isotopic and synchrotron-based spectroscopic analyses to evaluate the phase distribution and corresponding isotope variation of K in the skeleton of scleractinian (Porites australiensis) corals at a seawater temperature range from 20 to 29 °C in aquaria culture experiments. Potassium in coral skeletons exists mainly as organic-K (K hosted in soluble and insoluble organic matrices) and carbonate-K (K incorporated into K 2 CO 3 and aragonite) phases of various proportions. Coral δ 41 K values vary substantially in both direction and magnitude from the modern seawater δ 41 K composition (∼0.12‰), showing marked deviations (Δ 41 K Coral-Sea) from −2.00 to 0.67‰. As seawater temperature increases, the organic-K fraction increases, whereas δ 41 K Coral decreases. The variation in δ 41 K Coral reflects the relative proportions of organic-bound K to carbonate-associated K. In most cases, coral intracrystalline organic matrices preferentially sequester isotopically lighter K whereas carbonate phases prefer heavier K. Distinguishable inter-colony difference in skeletal δ 41 K of corals growing under the same culturing conditions reveals the influence of physiological controls on K partitioning and isotope fractionation. Although calcification rate correlates with temperature to different degrees in the studied corals, likely reflecting control of the difference in zooxanthellae density, we infer that calcification rate is not a major controlling factor on skeletal δ 41 K. Rather, skeletal δ 41 K correlates closely with K phase partitioning, which is ascribed to temperature-sensitive physiological modulation. [ABSTRACT FROM AUTHOR]

The reactions of IMes-HCl with bimetallic iron-copper clusters were investigated and it showed that interconversions among bimetallic Fe xCu y(CO) zn- clusters were induced by IMes-HCl. The reaction priority of IMes-HCl with fragments in Fe xCu y(CO) zn- was also investigated and the reaction behaviors of zero valent Fe(CO)4 and divalent Fe(CO)4 with IMes-HCl were discussed. [ABSTRACT FROM AUTHOR]

The objectives of this study were to encapsulate the Bifidobacterium bifidum F-35 into whey protein for the production of one-layer microcapsules, and then the microcapsules were covered by sodium alginate to produce double-layer microcapsules for examining the effectiveness of microcapsules in set yogurt. The reinforced treatment by double layer exhibited a significant increase ( P < 0.05) in B. bifidum F-35 count more than the treatments of free cells and one-layer microcapsules. Microcapsules of double layer in yogurt led to record a value of titratable acidity that was 1.51 in comparison with the treatments of one layer and free cells that were 1.65 and 1.73, respectively. The hardness values were recorded as 206.88 at the treatment of double layer and 130.31 at the treatment of one layer after 7 days of storage. Microencapsulation of double layer caused a slight bitterness and creamy texture in yogurt, whereas the samples of free cells were described to have sour and bad texture. [ABSTRACT FROM AUTHOR]

Abstract: Magnesium isotopes have been shown to fractionate significantly during continental weathering, however, the degree and direction of fractionation varies from one study to the next, and the main factors that control Mg isotope fractionation during weathering have yet to be delineated. Here, we report Mg contents and isotopic compositions for two ∼10m deep drill cores through bauxites developed on Columbia River Basalts (CRBs). Samples from these two drill cores have very low MgO contents (0.12–0.25wt.%) and variable but high δ26Mg values (from −0.1 to up to +1.8, the heaviest isotopic composition ever reported for Mg) relative to the average values of fresh CRBs (δ26Mg=−0.23±0.07 and MgO=5.9wt.%). These features reflect the near complete loss of Mg in the isotopically heavy regolith. The most highly weathered bauxites at the tops of the profiles have the lowest δ26Mg values, reflecting the addition of isotopically light eolian dust. Excluding these samples, δ26Mg in bauxites displays a weak, positive correlation with gibbsite abundance, suggesting that gibbsite preferentially retains 26Mg in the bauxites. The integrated Mg isotopic fractionation factors between bauxite and fluid (Δ26Mgbauxite-fluid), inferred from Rayleigh fractionation calculations, vary from 0.05‰ to 0.4‰, which is similar to the range inferred from previous studies of igneous rock weathering profiles, though none of these previous studies found the extremely heavy δ26Mg and massive Mg depletion seen here. Collectively, studies of weathering profiles suggest loss of isotopically light Mg from the continents, which must contribute to the very light δ26Mg seen in river water and seawater. [Copyright &y& Elsevier]

Abstract: Endothelial cell (EC) dysfunction is involved in the pathogenesis of contrast-induced acute kidney injury, which is a major adverse event following coronary angiography. In this study, we evaluated the effect of contrast media (CM) on human EC proliferation, migration, and inflammation, and determined if heme oxygenase-1 (HO-1) influences the biological actions of CM. We found that three distinct CM, including high-osmolar (diatrizoate), low-osmolar (iopamidol), and iso-osmolar (iodixanol), stimulated the expression of HO-1 protein and mRNA. The induction of HO-1 was associated with an increase in NF-E2-related factor-2 (Nrf2) activity and reactive oxygen species (ROS). CM also stimulated HO-1 promoter activity and this was prevented by mutating the antioxidant responsive element or by overexpressing dominant-negative Nrf2. In addition, the CM-mediated induction of HO-1 and activation of Nrf2 was abolished by acetylcysteine. Finally, CM inhibited the proliferation and migration of ECs and stimulated the expression of intercellular adhesion molecule-1 and the adhesion of monocytes on ECs. Inhibition or silencing of HO-1 exacerbated the anti-proliferative and inflammatory actions of CM but had no effect on the anti-migratory effect. Thus, induction of HO-1 via the ROS-Nrf2 pathway counteracts the anti-proliferative and inflammatory actions of CM. Therapeutic approaches targeting HO-1 may provide a novel approach in preventing CM-induced endothelial and organ dysfunction. [Copyright &y& Elsevier]

Abstract: Mineralogical, chemical, and Li and Nd isotopic compositions of two drill cores (8–9m deep) through bauxites developed on the Miocene Columbia River Basalts document the changes associated with basalt weathering, provide insights into the processes involved, and allow us to examine the overall influence of chemical weathering on juvenile (basaltic) crust. Gibbsite, hematite, ±kaolinite, halloysite, goethite, and maghemite are the weathering products in the bauxites. Quartz is observed near the tops of the cores and its abundance decreases progressively with depth; no quartz is observed below five meters depth in either core. Most major and trace elements, including “mobile” and some “immobile” elements are severely depleted in the bauxites. Niobium is less mobile relative to the rare earth elements, thus chemical weathering attenuates the negative Nb anomaly in the continental crust. Li and Nd are strongly depleted relative to fresh basalt, and both increase systematically towards the surface in the quartz-bearing samples while δ7Li and ε Nd values decrease systematically towards the surface in these same samples. Both Li and Nd were likely lost from the bauxites through leaching. The systematic enrichment of Li, Nd, and quartz, as well as the less radiogenic Nd isotopic composition at the tops of both profiles reflects 20–60wt.% addition of an eolian component to the soils. The eolian dust is unlikely to have experienced significant post-depositional weathering due to the relatively high Li contents near the tops of the profiles, and, therefore, the low δ7Li and ε Nd values suggest that the dust came from an old, weathered region of the continent. Our results demonstrate that lithium isotopes are sensitive tracers of chemical weathering, particularly in extreme weathering settings, and support the hypothesis that chemical weathering influences the mass and composition of the continental crust. [Copyright &y& Elsevier]

BaCeAGdO (A = In, Zr, Ta; x = 0, 0·1) ceramics were synthesized by solid-state reaction method. Microstructure and electrical properties of BaCeAGdO ceramics were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and complex impedance analysis at intermediate temperatures of 573-1073 K in different atmospheres. BaCeGdO, BaCeInGdO and BaCeZrGdO ceramics exhibit a single cubic perovskite structure. BaCeInGdO ceramic has the highest conductivity of 4·6 × 10 S·cm in air at 1073 K. BaCeInGdO and BaCeZrGdO ceramics exhibit an excellent chemical stability against boiling water. Indium is a suitable doping element to promote the sintering densification and to enhance both electrical conductivity and chemical stability of Gd-doped BaCeO at operating temperatures. [ABSTRACT FROM AUTHOR]

Follicular atresia is a process of spontaneous degradation of follicles, hindering growth and development in the mammalian ovary. Previous studies showed that follicular atresia was caused by apoptosis of granulosa cells, for which a number of apoptosis-related genes have already been identified. The roles of p53 in apoptosis of mouse granulosa cells and its post-translational modification are still unclear. The main objective of this study was to explore the roles of p53 in mouse granulosa cells. We found that mouse p53b, but not p53a, could be SUMOylated by SUMO-1 at lysine 375, which was essential for the protein stability of p53b in a dose-dependent manner. Immunofluorescent staining showed that wild p53b was located in the nucleus of granulosa cells, while its mutation of SUMOylated site (K375R) was localized in both nucleus and cytoplasm, implying that SUMOylation was necessary for the nuclear localization of p53b in granulosa cells. Overexpression of wild-type p53b, but not the mutation of SUMOylation site (K375R), significantly induced the expression of apoptosis-related gene, Bax, and increased the level of apoptosis in granulosa cells. This suggested that SUMO-1 modification of p53b was essential for inducing apoptosis in granulosa cells. Our results provide strong evidences that modification of p53b by SUMO-1 at lysine 375 was necessary for its activity to induce apoptosis in mouse granulosa cells, and it was involved in the regulation of p53b protein stability and nuclear localization. This implies that modification of p53b by SUMO-1 might regulate follicular atresia by inducing the apoptosis of ovarian granulosa cells in mice. [ABSTRACT FROM AUTHOR]

Abstract: Phytochemical investigation of 70% aqueous EtOH extract of Cistanche sinensis led to the isolation of fifteen compounds (1–15), including nine phenylethanoid glycosides (PhGs, 1–9), five iridoid glycosides (10–14), and one lignan glycoside (15). Their structures were determined on the basis of 1D- and 2D-NMR experiments and by comparison with physical data of known compounds. Among the isolated compounds, 1 was identified as a new compound, three compounds (9, 14, and 15) were firstly reported from the genus Cistanche, and seven compounds (2–6, 11, and 12) were isolated from C. sinensis for the first time. PhGs with a 6′-O-rhamnosyl moiety such as cistansinenside B (1), poliumoside (7), and 2′-O-acetylpoliumoside (9) could serve as chemotaxonomic markers to differentiate C. sinensis from other species of Cistanche. [Copyright &y& Elsevier]

Abstract: Sildenafil is a cGMP-specific phosphodiesterase type 5 inhibitor that augments cGMP accumulation following the activation of soluble guanylate cyclase (sGC). In this study, we investigated whether sildenafil promotes the production of the sGC-stimulatory gases, carbon monoxide and nitric oxide, by stimulating the expression of the inducible isoforms of heme oxygenase (HO-1) and nitric oxide synthase (iNOS) in vascular smooth muscle cells (SMCs). Sildenafil increased HO-1 expression and potentiated cytokine-mediated expression of iNOS and NO synthesis by SMCs. The induction of HO-1 was unaffected by the sGC inhibitor 1H-(1,2,4)oxadiazolo[4,3-α]quinozalin-1-one (ODQ) or the protein kinase G inhibitor (8R,9S,11S)-(-)-2-methyl-9-methoxyl-9-methoxycarbonyl-8-methyl-2,3,9,10-tetrahydro-8,11-epoxy-1H,8H,11H-2,7b,11a-triazadibenzo(a,g)cyclocta9(cde)trinen-1-one (KT 5823). However, the sildenafil-mediated increase in HO-1 promoter activity was abolished by mutating the antioxidant responsive elements in the promoter or by overexpressing a dominant-negative mutant of NF-E2-related factor-2 (Nrf2). Furthermore, the induction of HO-1 by sildenafil was accompanied by an increase in reactive oxygen species (ROS) and blocked by N-acetyl-l-cysteine and rotenone. In contrast, the enhancement of cytokine-stimulated NO synthesis by sildenafil was prevented by ODQ and the protein kinase A inhibitor (9S,10S,12R)-2,3,9,10,11,12-hexahydro-10-hydroxy-9-methyl-1-oxo-9,12-epoxy-1H-diindolo(1,2,3-fg:3′,2′,1′-kl)pyrrolo(3,4-i)(1,6)benzodiazocine-10-carboxylic acid hexyl ester (KT 5720) and duplicated by lipophilic analogs of cGMP. In conclusion, these studies demonstrate that sildenafil stimulates the expression of HO-1 and iNOS via the ROS-Nrf2 and sGC-cGMP pathway, respectively. The ability of sildenafil to block the catabolism of cGMP while stimulating the synthesis of sGC-stimulatory gaseous monoxides through the induction of HO-1 and iNOS provides a potent mechanism by which cGMP-dependent vascular actions of this drug are amplified. [Copyright &y& Elsevier]