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Boolean functions used in symmetric-key encryption should have high higher-order nonlinearity to resist several known cryptographic attacks, such as algebraic attacks and low-degree approximation attacks. The higher-order nonlinearity also plays an important role in coding theory and theoretical computer science, since it relates to the covering radius of Reed–Muller codes and the Gowers norm, respectively. It is well-known that bent functions have the highest nonlinearity in an even number of variables and thus they possess the best ability to withstand fast correlation attacks and best affine approximation attacks. However, there is currently limited knowledge regarding the higher-order nonlinearity of bent functions because computing the higher-order nonlinearity, or even providing tight lower bounds, is an extremely hard task. In 1974, Dillon proposed two well-known classes of bent functions based on partial spread (in brief, PS), called PS − and PS + , respectively. He also exhibited a subclass of bent functions in PS − , known as partial spread affine plane(PS a p for short). In this paper, we provide a lower bound on the third-order nonlinearity of the simplest PS a p bent functions in n variables, where n ≥ 6 is even, by calculating the nonlinearities of all second-order derivatives of this kind of bent functions. Compared to the two known lower bounds on the third-order nonlinearity given by Carlet and Tang et al. respectively, our lower bound is much better than these two ones. [ABSTRACT FROM AUTHOR]

The Mg isotopic compositions of siliciclastic components (δ26Mgsili) of sediments and sedimentary rocks have been commonly used to constrain the intensity of continental weathering, based on observations of, (1) an upward enrichment of 26Mg in modern weathering profiles, (2) preferential uptake of 26Mg in soil clays, and (3) general positive correlations between weathering intensities and δ26Mgsili values. However, not all weathering profiles display an upward increase of δ26Mgsili, and not all soil clays enrich in 26Mg, complicating the interpretations of δ26Mgsili data of sediments and sedimentary rocks. To further explore the controls of δ26Mgsili of sediments and sedimentary rocks, here we measured δ26Mgsili, mineralogical compositions and major element compositions of deep sea sediments from South China Sea (SCS) and carbonate rock samples from two late Paleozoic sections in South China. Carbonate samples show decreasing trends of both normalized Mg concentration (Mgnorm) and δ26Mgsili values with the increase of weathering intensity, while SCS sediments samples do not show any correlation between Mgnorm or δ26Mgsili values and weathering intensity. A three-stages weathering model is developed to explain the observed Mgnorm and δ26Mgsili data. In the new model, weathering can be divided into three stages, (1) the preliminary weathering stage characterized by dissolution of primary minerals and formation of secondary clay minerals in saprolite, (2) the transitional stage with massive vermiculite and chlorite formation on the bottom of soil, and (3) the advanced stage showing dissolution of vermiculite and chlorite in the top of soil. The new model explains an δ26Mgsili increase and Mgnorm decrease with an increase weathering intensity in preliminary weathering stage and decrease of Mgnorm and δ26Mgsiliwith increase weathering intensity in advanced weathering stage. The revised weathering model warrants the application of Mg isotope in the study of continental weathering in deep time. [ABSTRACT FROM AUTHOR]

The emergence of the Ediacara biota soon after the Gaskiers glaciation ca. 580 million years ago (Ma) implies a possible glacial fuse for the evolution of animals. However, the timing of Ediacaran glaciation remains controversial because of poor age constraints on the ∼30 Ediacaran glacial deposits known worldwide. In addition, paleomagnetic constraints and a lack of convincing Snowball-like cap carbonates indicate that Ediacaran glaciations likely did not occur at low latitudes. Thus, reconciling the global occurrences without global glaciation remains a paradox. Here, we report that the large amplitude, globally synchronous ca. 571–562 Ma Shuram carbon isotope excursion occurs below the Ediacaran Hankalchough glacial deposit in Tarim, confirming a post-Shuram glaciation. Leveraging paleomagnetic evidence for a ∼90° reorientation of all continents due to true polar wander, and a non-Snowball condition that rules out low-latitude glaciations, we use paleogeographic reconstructions to further constrain glacial ages. Our results depict a 'Great Ediacaran Glaciation' occurring diachronously but continuously from ca. 580–560 Ma as different continents migrated through polar–temperate latitudes. The succession of radiation, turnover and extinction of the Ediacara biota strongly reflects glacial–deglacial dynamics. [ABSTRACT FROM AUTHOR]

In this paper, a new optimization design strategy is explored to achieve a rapid design of lightweight structures for unmanned aerial vehicles (UAVs) using honeycomb sandwich panels. Based on the existing performance equivalent method of honeycomb core material, an effective mechanical property homogenization model of honeycomb material is proposed and applied to finite element analysis. A finite element model is established to analyze the mechanical response of honeycomb sandwich panels under different bending loads, and the rationality of the model is verified by mechanical tests. The error between the simulation results and the experimental results is about 10%. Based on the variable density method and rational approximation of material properties interpolation method, a topology optimization model with the minimum structural flexibility as the objective is constructed. By comparing with the experiment-based design scheme, it is found that the optimized design scheme has a more reasonable structure and better performance. The optimized design can effectively reduce the structural weight and improve the load transfer path while ensuring structural stiffness. In this way, the influence of stress concentration and large deformation on the structure is avoided, which is of great significance for the design of UAV structures. [ABSTRACT FROM AUTHOR]

Ultra-broadband and high absorption properties are significant for energy harvesting, solar cells, fire detection and imaging. An ultra-broadband and high absorption metamaterial absorber is proposed, which consists of a grid structure and a SiO2 rectangular structure. The simulation results of the metamaterial absorber show that the absorber has an absorption rate of more than 90% with a bandwidth of 3815 nm centered at about 2045 nm. Due to the asymmetry of the absorber structure, it is sensitive to the polarization angle, but still has certain polarization independence and wide-angle absorption characteristics in the whole band (300 ~ 4000 nm). The analysis shows that surface plasmon resonance, local surface plasmon resonance, cavity resonance, and coupling between resonant modes play a dominant role in the broadband and absorption of the absorber. The absorber with broadband and high absorption performance has great potential for solar energy harvesting, thermoelectric, and thermal emitter applications. [ABSTRACT FROM AUTHOR]

Gender-affirming surgery (GAS) is often sought after to alleviate the distress of those who suffer from gender dysphoria (GD). While many studies have shown that a significant percentage of people benefit from this procedure, a number of individuals later regret their decision of undergoing surgery. Studies have illustrated what regret depicts, categorizing regret based on intensity, persistency, and sources, in the hopes to prevent an unwanted irreversible intervention. Here, an in-depth interview with a 35-year-old transwoman from Taiwan who underwent feminizing GAS at the age of 31 illustrates her unique cultural upbringing and the course of her regret. Her experience best matches the characteristics of true regret and major regret based on the classifications of Pfäfflin and Wiepjes, respectively, indicating that she expected GAS to be the solution to her personal acceptance issue, but, in retrospect, regretted the diagnosis and treatment as her problems were not solved and worsened to the extent of secondary dysphoria. This case report hopes to shed light on the complexity of GD and regret after GAS, while encouraging the pre-surgical evaluation of psychological comorbidities and post-surgical psychotherapy, and ensuring that patients are informed and give full consent. In addition, more elaborate, long-term, large-scale qualitative research, especially within more conservative cultural settings, is needed. [ABSTRACT FROM AUTHOR]

Centrifugal casting is an established molding method to prepare ceramics with high strength and high reliability and it has been well demonstrated in Al 2 O 3. However, it has not yet been applied to Al 2 O 3 nanocrystalline ceramic with < 100 nm grain size, primarily due to the unavailability of high-quality α -Al 2 O 3 nanoparticles. In addition, ultrafine nanoparticles may be difficult to cast from the solution unless high-speed ultracentrifuge (e. g., >60,000 rpm) is used. Here we addressed these two challenges by home-made dispersed α -Al 2 O 3 nanoparticles with 10 nm average particle size and HCl-assisted casting under a "normal" centrifuge condition and report the first attempt to produce Al 2 O 3 nanocrystalline ceramic by centrifuge casting and pressureless sintering. The sintering kinetics and microstructure were analyzed, which assists the design of optimal two-step sintering schedule. We showed that dense Al 2 O 3 nanocrystalline ceramic with 65 nm average grain size and ultra-uniform microstructure (the standard deviation of the grain size distribution to the average grain size is 0.358) can be obtained by two-step sintering at 1175 °C without holding followed by holding at 1025 °C for 20 h. The ultra-uniform microstructure may result from the denser and more uniform packing of particles in the green bodies produced by centrifugal casting. The two-step sintered Al 2 O 3 nanocrystalline ceramic has a microhardness of 19.9 GPa. The microhardness indicates potential softening (inverse Hall-Petch relationship) of Al 2 O 3 nanocrystalline ceramic at such a grain size. • Centrifugal casting of the green bodies from the α -Al 2 O 3 nanoparticles under a normal centrifuge condition. • Al 2 O 3 ceramic with 65 nm grain size and uniform grain size distribution was prepared by two-step sintering. • Centrifugal casting offers uniform nanoparticle packing in the green bodies. • Two-step sintered Al 2 O 3 nanocrystalline ceramic has 19.9 GPa average microhardness. [ABSTRACT FROM AUTHOR]

In this paper, the mechanical behavior and damage evolution of CFRP laminates under three-point bending loads were investigated. Based on the three-dimensional Hashin failure criterion and cohesive zone method, a progressive damage analysis model was constructed to predict seven different failure modes, and an improved stiffness matrix degradation law was proposed. Numerical simulations were performed using ABAQUS finite element software and UMAT user subroutines and verified by three-point bending tests. The experimental results show that the relative errors of the flexural strength and flexural modulus of the current model simulation results and the experimental data were −3.10% and −2.70%, respectively, and the damage evolution process after the ultimate load was accurately predicted. Meanwhile, the predicted final failure and damage modes were consistent with the micrographs of the failed specimens. [ABSTRACT FROM AUTHOR]

Through the Earth's ∼ 4.54 billion year history, icehouse climates have been relatively short-lived but have exerted a significant impact on the evolution of the habitable environment. These icehouse episodes, such as those that occurred in the Cryogenian, mid-Ediacaran, Late Ordovician, and Late Paleozoic, developed through the complex interaction of Earth System processes; however, there is still ongoing debate regarding the causes, processes, and consequences of these glaciations. To improve our understanding of the past history of icehouse climates and the responses of the Earth System, we present this new special issue entitled The Earth System during Icehouse Climate Modes: Contributions from Glacial Records in China. This special issue includes eighteen papers that focus on four major icehouse events: the Cryogenian Snowball Earth glaciations (Sturtian and Marinoan global glaciations), the Ediacaran glaciation, the Ordovician glaciation, and the late Paleozoic Ice Age. This collection of papers provide novel insights into glacial processes, marine environments, and chemical weathering through key intervals of Earth History. We anticipate that this special issue will attract wide interest across the geosciences field. [ABSTRACT FROM AUTHOR]

Termination of the Marinoan global glaciation (650–635 million years ago, Ma) was immediately followed by the diversification of eukaryotes and possible occurrence of animals, suggesting the potential linkage between biological evolution and global glaciation. It is proposed that the post-glacial eukaryote evolution might have been triggered by environmental stress imposed by the extreme pan-glacial condition. However, how life survived through the global glaciation remains speculative. Neither is known about the habitability when the ocean was completely or mostly frozen. In this study, we explore the marine carbon and sulfur biogeochemical cycles during the Nantuo (Marinoan) glaciation (650–635 Ma) in South China. Both organic carbon (δ13C org) and pyrite sulfur isotopes (δ34S py) show significant stratigraphic variations, suggesting active biogeochemical cycles in the pan-glacial condition. By coupling both δ13C org and δ34S py data, we develop numerical models to constrain marine productivity and redox conditions during the Nantuo glaciation. The marine primary productivity showed a sharp decline in the onset of glaciation and recovered right before the cap carbonate precipitation. An episodic recovery of primary productivity was observed in the non-glacial interval between the two glacial episodes. In contrast, the marine productivity was still suppressed in initial deglaciation, during which the continental weathering was intense, presumably indicating high atmospheric CO 2 level and low seawater pH value. The final recovery of marine primary productivity occurred in the topmost of Nantuo Formation, when the weathering intensity was already low. Therefore, the active biogeochemical cycle implies a sustained habitability, warranting the survivorship in the pan-glacial ocean, while the persistently low and delayed recovery of marine productivity might have imposed environmental stress for tens of million years, paving the way for the evolution of animals. [ABSTRACT FROM AUTHOR]

The purpose of this investigation is to study the performance degradation mechanism of CRRP composite materials used in the structure of a solar UAV under acid rain environment and to provide references for the structural design of the solar UAV. An aging test was designed according to the actual working conditions of the solar unmanned aerial vehicle and was carried out by continuously immersing the composite material in both deionized water and an acidic solution with a pH of 2.0 at 60°C. The mechanical behavior of the composites was studied through a three-point bending test. The results showed that after 120 days of aging test, the composite material exhibits different characteristics in the two conditions. The composite material under the hygrothermal conditions finally reached the equilibrium moisture absorption content of 1.07%, and the flexural strength decreased by 8.77%. The composite material under acidic conditions deviated from the Fick behavior in the final stage of the test, and the final moisture content was 2.88%, and the bending strength decreased by 26.43%. Several typical empirical models were analyzed, and a hyperbolic tangent function empirical model with moisture content as the main variable was used to predict the CFRP flexural strength degradation process, and good results were obtained. The effect of aging conditions on the microstructure of composite materials was observed by SEM, and the aging mechanism of composite materials was analyzed. The corrosion of the polymer matrix and the debonding of the fiber/matrix interface are the root causes of the performance degradation of composite materials. [ABSTRACT FROM AUTHOR]

• Cancer is a risk factor for tuberculosis with time-dependent association. • The highest risk of tuberculosis was observed around the time of cancer diagnosis. • The confounding effect of unmeasured confounders were adjusted by external database. • Cancers in respiratory tract, upper digestive tract, and hematology were at risk. • Screening and case detection for tuberculosis should be considered. We aimed to investigate the time-dependent association between cancer and the risk of tuberculosis (TB) before and after cancer diagnosis. This population-based cohort study incorporated the National Health Insurance Research Database and the National Health Interview Survey in Taiwan to estimate TB risk in cancer and noncancer populations. We estimated the period-specific incidence rate ratio (IRR) between cancer and risk of TB and used Cox proportional hazards models to estimate the average hazard ratio between cancer and TB during the peridiagnostic period. From 2001 to 2015, 457 673 cancer and 3 738 122 noncancer individuals were enrolled. After stratifying the IRR of TB by year relative to the date of cancer diagnosis, the peak IRRs clustered in the year before and after the index date. In the peridiagnostic period of cancer, the adjusted hazard ratio was 2.29 (95% CI, 2.22–2.35) using the Cox model and 2.20 (95% CI, 2.09–2.32) after adjustment for missing confounders. Patients with cancers in the respiratory tract, upper digestive tract, and hematologic system were at the highest risk for TB. Cancer is an independent risk factor for TB, with the highest risk observed around the time of cancer diagnosis. [ABSTRACT FROM AUTHOR]

Background. Cardiovascular disease (CVD) is closely related to arterial elasticity and hemodynamics. Exercises have been reported to immediately decrease arterial apparent elasticity and regulate hemodynamic variables. However, the relationship between them and exercise intensity remains elusive. The purpose of this study was to determine the acute effects of different intensities of acute cycling exercise on carotid arterial apparent elasticity and hemodynamics. Methods. 32 healthy men (age: 19.4 ± 0.6 years) attended the laboratory on five occasions and completed cycling acute exercise for 20 minutes at five intensities (40%, 50%, 60%, 70%, and 80% heart rate reserve (HRR)). At the right carotid artery, center-line velocity and arterial inner diameter waveforms were examined before and immediately after exercise. Based upon the measured data, the classical hemodynamic theory was used to calculate the apparent elasticity and the local hemodynamic variables. Results. The arterial apparent stiffness and the apparent elastic modulus following acute cycling exercise at 60% to 80% HRR were significantly higher than baseline. The mean center-line velocity accelerated from 50% to 80% HRR, but no intensity of intervention altered mean blood flow. Immediately after intervention, the mean wall shear stress and oscillatory shear index increased. Conclusions. Aerobic cycling intervention, with intensity from 40% to 80% HRR, did not change the brain blood supply. A bout of cycling intervention decreased apparent elasticity, and there was an intensity-dependent effect on apparent elasticity and hemodynamic variables. This study would provide referable data for the further study on the effects of aerobic exercise on arterial hemodynamics and elasticity and underlying physiological mechanisms. [ABSTRACT FROM AUTHOR]

Background Method Results Conclusion The potential link between environmental pollutants, including metals, and schizophrenia development remains debated. This study aimed to explore the association between plasma levels of three non‐essential metals—barium (Ba), tungsten (W), and uranium (U)—and schizophrenia risk among Chinese individuals.We recruited a total of 221 patients and 219 healthy controls. Plasma levels of three non‐essential metals were measured using inductively coupled plasma mass spectrometry. We employed unconditional logistic regression and Bayesian kernel machine regression (BKMR) to explore the relationship between exposure to multiple metals and the risk of schizophrenia.Logistic regression analysis revealed that the highest quartile (Q4) of W had an odds ratio (OR) of 1.87 (95% CI: 1.08–3.21) compared to the lowest quartile (Q1), with a significant P‐trend of 0.017. For U, the ORs (95% CI) for Q2, Q3, and Q4 were 2.06 (1.19–3.56), 1.99 (1.15–3.44), and 1.74 (1.00–3.00), respectively. BKMR analyses revealed a progressive increase in the risk of schizophrenia with increasing cumulative levels of the three metals at concentrations below 35%, with U playing a major role in this association. U showed a non‐linear positive correlation with schizophrenia, particularly at the 75th percentile level. Moreover, potential interactions were observed between W and Ba, as well as between W and U.Higher plasma W and U concentrations were positively associated with the risk of schizophrenia, which was potentially related to the severity of symptoms in schizophrenic patients. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) have been widely used in metal-ion detection and are promising candidates for applications in chemical sensors and biomedicine. However, the abundant functional species on the surface of CDs often result in simultaneous response to multiple metal ions and poor selectivity. To realize the selective detection of metal ions, it is crucial to establish the correlation between the surface structure of CDs and metal-ion detection. Herein, CDs with different surface structures were synthesized under harsh thermal microwave reaction. The CDs have citric acid-like, polyethylene glycol-like (PEG-like), or polyethyleneimine-like (PEI-like) surfaces in combination with 4-hydroxy-1H-pyrrolo[3,4-c]pyridine-1,3,6(2H,5H)-trione (HPPT); and amide bonds were found in the lactam structure of HPPT. Different surface species can be distinguished to recognize Fe3+, Cu2+, and Hg2+ ions. Accordingly, organic species of PEG, HPPT, and PEI were used to functionalize carbon nanoparticles to prepare targeting functionalized CDs. The PEG/CDs and HPPT/CDs have high selectivity for Fe3+ and Hg2+ ions, while the PEI/CDs have high selectivity for Cu2+ ions, eliminating the interference of -NH combining Co2+, Mn2+, and Ni2+ ions. Our findings shed light on the correlation between the surface structure of CDs and selective detection of metal ions, which can expand the sensing applications of CDs. [ABSTRACT FROM AUTHOR]

The standard solar model proposes that the solar luminosity was 30% lower than the present level at 4.5 billion years ago (Ga). At low solar radiation, the climate model predicts that the Earth should have been completely covered by ice in the first 2 billion years, i.e. in the snowball Earth climate mode, when the atmospheric CO2 content was at the present level. However, snowball Earth condition is inconsistent with various sedimentological, paleontological, and geochemical evidence. Such controversy is collectively known as the 'Faint Young Sun' (FYS) paradox. Though various models have been proposed, the FYS paradox has not yet been resolved. In this study, we develop a model by considering the ocean–atmosphere coupling to show that high atmospheric CO2 level could be sustained at low seawater pH. The modeling result indicates that 0.1 bar atmospheric CO2 level that was required to prevent snowball Earth in early Archean could be sustained at seawater pH of 6.8–7.2. Although the absence of siderite in Archean paleosols has been used to argue against high atmospheric CO2 level, we suggest that siderite precipitation in paleosols was not controlled by the atmospheric CO2 level alone. Instead, siderite could precipitate in anoxic conditions with various amount of CO2 in the atmosphere, suggesting siderite cannot be used to reconstruct the atmospheric CO2 level. Therefore, the new model suggests that the snowball Earth condition could be prevented by the coupling of atmosphere and ocean systems, and thus the emergence of the ocean in the very beginning of Earth evolution might be the key to the subsequence evolution of habitability. [ABSTRACT FROM AUTHOR]

A series of Dy3+ and Dy3+/Eu3+ co-doped LiY(PO 3) 4 phosphors are prepared by sol-gel combustion method, followed by annealing treatment at 700 °C for 10 min. XRD patterns and TEM images show that the LiY 1-m-n Dy m Eu n (PO 3) 4 phosphors are characterized by monoclinic phase and regular short rod or nearly spherical granules. Excited at 363 nm, the Dy3+ single doped LiY(PO 3) 4 phosphors have two intense emission peaks at 482 nm and 574 nm. Its chromaticity coordinate point is centred at (0.305 ± 0.003, 0.33 ± 0.015) and its CCT is higher than 6700 K. By introducing Eu3+ ions to LiY 0.96 Dy 0.04 (PO 3) 4 phosphors, chromaticity coordinate point and CCT of LiY 0.96-n Dy 0.04 Eu n (PO 3) 4 phosphors can be adjusted almost linearly due to energy transfer between Dy3+ ions and Eu3+ ions. The corresponding CCT of 4927–6052 K and chromaticity coordinate point of (0.3334 ± 0.0136, 0.3492 ± 0.0014) can be achieved for LiY 0.96-n Dy 0.04 Eu n (PO 3) 4 (n = 0.03–0.05) phosphors with high luminescence thermal stabilities and energy transfer efficiency of more than 18.99%. These results indicate that Dy3+/Eu3+ co-doped LiY(PO 3) 4 phosphors are expected to be a promising single matrix white emitting phosphors with tunable white-light emission for NUV-WLEDs. Image 1 • LiY(PO 3) 4 :Dy/Eu phosphor can be prepared by sol-gel combustion method. • LiY(PO 3) 4 :Dy/Eu phosphors show a tunable white-light emission. • LiY 0.96-n Dy 0.04 Eu n (PO 3) 4 (n > 0.03) has high ET efficiency (>19%). • LiY(PO 3) 4 :Dy/Eu phosphor has high PL thermal stabilities (83% at 180 °C). • LiY 0.92 Dy 0.04 Eu 0.04 (PO 3) 4 show a CCT of 5398 K and coordinate (0.335, 0.35). [ABSTRACT FROM AUTHOR]

The effect of engineered nanoparticles on the mobility of co-existing contaminants has been increasingly studied, while the reverse effect receives little attention. This study provides results from investigating the effect of oxytetracycline (OTC) on the mobility of oxidized multi-walled carbon nanotubes (O-MWCNTs) in quartz sand (QS) columns at various solution ionic strengths (ISs) and pHs. The mobility of O-MWCNTs in QS columns was significantly enhanced by the presence of OTC under all of the tested solution conditions (IS: 0.1, 1.0, and 10 mM; pH: 3.0, 5.5, and 8.5), with an increase of 8.6–50.9%. Such enhancement was nonlinear over OTC concentration, which firstly increased (0 to 2.5 mg L −1 OTC) and then decreased (2.5 to 20 mg L −1 OTC) at pH 5.5. The major contributor to the OTC-enhanced O-MWCNTs mobility was competition of the two analytes for adsorption sites on the QS surface. Batch attachment results show that the adsorption of O-MWCNTs in the presence of OTC onto QS was also nonlinear with OTC concentration (firstly decreased and then increased with increasing OTC) at pH 5.5, which gave the plausible explanation for the nonlinear enhancement of O-MWCNTs transport in QS columns by the presence of OTC. In turn, both the carrier and competition actions of O-MWCNTs determined the mobility of OTC in QS columns and the carrier action was stronger when more OTC was associated with O-MWCNTs in the influent. These results imply that the mobility of O-MWCNTs in OTC polluted water and soil can be significantly stronger than that in non-polluted area. Capsule OTC can increase the migration of O-MWCNTs mainly through the competition for adsorption sites on collectors. [ABSTRACT FROM AUTHOR]

Abundant chert bands and nodules are discovered throughout the Mesoproterozoic Wumishan Formation (∼1.5 Ga) in the North China Block. The middle part of the Wumishan Formation consists of cyclic deposition of calcareous shale, massive microbial dolostone (thrombolites and stromatolites), and laminated dolostone. Chert bands occur most abundantly in the laminated dolostone, although they are also found with lower abundance in other lithologies. Chert bands are normally parallel to the bedding plane, and show soft-deformation structures, suggesting early silicification at or near the water–sediment interface. The Wumishan chert is composed of two types of silica fabric: the microcrystalline and cryptocrystalline quartz that derives from the replacement of host dolomitic rock, and the mosaic/chalcedonic quartz, representing typical void-filling precipitation. We measured the germanium/silica ratios (Ge/Si) and the REE compositions of the chert bands/nodules collected from a 60 m interval in the middle part of the Wumishan Formation in the Mopanyu section. Ge/Si ratios of the buck samples, measured by ICP-MS, range from 13.6 to 35.6 μmol/mol. Additional LA-ICP-MS analyses allow the measurements of individual silica fabric, providing more detailed information about the geochemistry of chert nodules and bands. Ge/Si ratios of the replacive chert vary between ∼10 and ∼20 μmol/mol, while the mosaic/chalcedonic quartz has wider range of variation (1.1–93.2 μmol/mol). These values are>1 order of magnitude higher than the modern seawater value (0.72 μmol/mol), but is within the range of hydrothermal fluids (3.4–51.3 μmol/mol, average = ∼13 μmol/mol, n  =  101), suggesting hydrothermal fluid as an important Si source. This conclusion is consistent with the positive Eu anomaly in the REE pattern. A mass balance calculation indicates that hydrothermal fluid would account for 10–15%, 20–25%, 40–55%, and >75% of Si for the fluid temperature of 100 °C, 150 °C, 200 °C, and 250 °C, respectively. Although large igneous provinces are not discovered in the North China Block during the deposition of the Wumishan Formation, the studied Wumishan cherts have significant contribution from hydrothermal fluid, which might be related to the early rifting activities in the North China Block before the breakup of supercontinent Nuna. [ABSTRACT FROM AUTHOR]

Non-biomineralizing Ediacaran macrofossils are rare in carbonate facies, but they offer valuable information about their three-dimensional internal anatomy and can broaden our view about their taphonomy and palaeoecology. In this study, we report a new Ediacaran fossil, Curviacus ediacaranus new genus and species, from bituminous limestone of the Shibantan Member of the Dengying Formation in the Yangtze Gorges area of South China. Curviacus is reconstructed as a benthic modular organism consisting of serially arranged and crescent-shaped chambers. The chambers are confined by chamber walls that are replicated by calcispars, and are filled by micritic sediments. Such modular body construction is broadly similar to the co-occurring Yangtziramulus zhangii and other Ediacaran modular fossils, such as Palaeopascichnus. The preservation style of Curviacus is similar to Yangtziramulus, although the phylogenetic affinities of both genera remain unresolved. The new fossil adds to the diversity of Ediacaran modular organisms. [ABSTRACT FROM PUBLISHER]

Background/Aim: Surgery and chemotherapy treatments of human laryngeal squamous cell carcinoma (HLSCC) may fail due to metastasis, in which epithelial-mesenchymal transition (EMT) plays an important role. TRPP2, a nonselective cation channel, is expressed in various cell types and participates in many biological processes. Here, we show that TRPP2 enhanced metastasis by regulating EMT. Methods: We used immunohistochemistry, western blotting, Ca2+ imaging, transwell and wound healing assays to investigate TRPP2 expression levels in HLSCC tissue, and the role of TRPP2 in invasion and metastasis of a human laryngocarcinoma cell line (Hep2 cell). Results: We found that TRPP2 protein expression levels were significantly increased in HLSCC tissue; higher TRPP2 levels were associated with decreased patient survival time and degree of differentiation and advanced clinical stage. Knockdown of TRPP2 by transfection with TRPP2 siRNA markedly suppressed ATP-induced Ca2+ release, wound healing, and cell invasion in Hep2 cells. Moreover, TRPP2 siRNA significantly decreased vimentin expression but increased E-cadherin expression in Hep2 cells. In the EMT signalling pathway, TRPP2 siRNA significantly decreased Smad4, STAT3, SNAIL, SLUG and TWIST expression in Hep2 cells. Conclusion: We revealed a previously unknown function of TRPP2 in cancer development and a TRPP2-dependent mechanism underlying laryngocarcinoma cell invasion and metastasis. Our results suggest that TRPP2 may be used as a biomarker for evaluating patient prognosis and as a novel therapeutic target in HLSCC. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) derived exosomes have been shown to have protective effects on the kidney in ischemia/reperfusion-induced renal injury. However, the key components in the exosomes and their potential mechanisms for the kidney protective effects are not well understood. In our current study, we focused on the abundant proteins in exosomes derived from MSCs (MSC-exo) and found that the C-C motif chemokine receptor-2 (CCR2) was expressed on MSC-exo with a high ability to bind to its ligand CCL2. We also proved that CCR2 high-expressed MSC-exo could reduce the concentration of free CCL2 and suppress its functions to recruit or activate macrophage. Further, knockdown of CCR2 expression on the MSC-exo greatly abolished these effects. Finally, we also found that CCR2 knockdown impaired the protective effects of MSC-exo for the renal ischemia/reperfusion injury in mouse. The results indicate that CCR2 expressed on MSC-exo may play a key role in inflammation regulation and renal injury repair by acting as a decoy to suppress CCL2 activity. Our study may cast new light on understanding the functions of the MSC-exo and these receptor proteins expressed on exosomes. [ABSTRACT FROM AUTHOR]

Precipitation of cap carbonate lithologies is a key feature of Cryogenian global glaciations. Negative carbonate carbon isotopic compositions (δ 13 C carb ) of these cap carbonates have been variably interpreted as massive drawdown of atmospheric CO 2 via extensive continental chemical weathering, methane oxidation, or postglacial upwelling. Each of these interpretations argues a non-steady state of carbon cycle in the aftermath of Marinoan global glaciation. To further explore the postglacial marine carbon cycle, we measured δ 13 C carb of cap carbonates from six localities in the Yangtze Platform, South China. The studied cap carbonates were deposited in a variety of sedimentary environments, ranging from the open shelf, slope, to basin facies. Cap carbonates deposited in different environments show distinct stratigraphic trends of δ 13 C carb . In the open shelf, δ 13 C carb profile of the Songlin section remains almost constant (−3 to −4‰), while the δ 13 C carb of the Jiulongwan section records a negative excursion, decreasing from −3.5‰ to −7‰. δ 13 C carb of cap carbonates deposited in the slope environment does not show stable stratigraphic trend. In the basin environment, δ 13 C carb demonstrates a sharp decline in the middle part of cap carbonates to the nadir value of ∼−11‰. The negative δ 13 C carb excursion is best interpreted in terms of oxidation of dissolved organic carbon (DOC), thus recording a pulse of ocean oxidation during cap carbonate precipitation. Clearly absence of negative δ 13 C carb excursion in all slope and most open shelf sections may imply that such oxidation event was not ubiquitous in the Yangtze Platform. We speculate that the renewed thermohaline circulation during deglaciation brought oxic surface water into ocean interior, which oxidized the basin environment of the Yangtze Platform. However, the deglacial thermohaline circulation was not strong enough to cause complete oxidation of the ocean. The sporadic oxidation in the open shelf, on the other hand, might result from the terrestrial influx of oxidant from postglacial continental weathering. Our study suggests that ocean oxidation, though sporadic, might have occurred during cap carbonate precipitation, and predated the first appearance of putative animal embryos. [ABSTRACT FROM AUTHOR]

We carried out an investigation on the effects of anthropogenic activities and climatic change on water resources in the Tarim River Basin, based on major hydro-climatic data, for the 1962–2007 period, and snow cover data from 2000 to 2011. A nonparametric basin-scale trend test of annual data shows a clear increasing trend for runoff, air temperature, and precipitation in the headwater catchment. We propose a copula-based approach, for studying the statistical dependence structure of hydro-climatic variables. We also constructed a two-dimensional tail estimator, to describe the nature of the tail dependence parameter, and as a means of studying its asymptotic properties. Tail dependence parameters demonstrate that air temperature has the greatest influence on runoff, followed by snow cover, precipitation, and evapotranspiration. Step-wise changes were noted to occur in the statistical dependence structure in dependence relationships, due to changes in major climate variables. Snow cover recession in the headwater catchment is consistent with the warming trend recorded by meteorological stations, but regional climate warming does not always result in snow cover reduction, owing to increased precipitation in regions such as the Aksu River basin, where a post-2000 increase in the snow cover area may have contributed to increased runoff, against a background of regional warming and wetting post-2000. Increased air temperature and precipitation, which resulted in increased runoff within the mountainous region, give rise to snowmelt and glacier-melt. Results from this study provide useful information for the planning and management of water resources in the study area. [ABSTRACT FROM AUTHOR]

Available Mg isotope data indicate that dolostones of different ages have overlapping range of Mg isotopic composition (δ 26 Mg) and there is no systematic difference among different types of dolomites. To further explore the Mg isotopic systematics of dolomite formation, we measured Mg isotopic compositions of Mesoproterozoic dolostones from the Wumishan Formation in North China Block, because dolomite formation in Mesoproterozoic might have been fundamentally different from the younger counterparts. Based on petrographic observations, three texturally-different dolomite phases (dolomicrite, subhedral dolomite and anhedral dolomite) are recognized in the Wumishan dolostones. Nevertheless, these three types of dolomites have similar δ 26 Mg values, ranging from −1.35‰ to −1.72‰, which are indistinguishable from Neoproterozoic and Phanerozoic dolostones. To explain δ 26 Mg values of dolostones, we simulate the Mg isotopic system during dolomite formation by applying the one-dimensional Diffusion–Advection–Reaction (1D-DAR) model, assuming that the contemporaneous seawater is the Mg source of dolostone. The 1D-DAR modeling results indicate that the degree of dolomitization is controlled by sedimentation rate, seawater Mg concentration, temperature, and reaction rate of dolomite formation, whereas Mg isotopic composition of dolostone is not only dependent on these factors, but also affected by δ 26 Mg of seawater and isotope fractionation during dolomite formation. Moreover, the 1D-DAR model predicts that dolomite formation within sediments has limited range of variation in δ 26 Mg with respect to limestones. Furthermore, the modeling results demonstrate that dolostone is always isotopically heavier than Ca-carbonate precipitated from seawater, explaining the systematic isotopic difference between dolostones and limestones. Finally, we can infer from the 1D-DAR model that early-formed dolostone at shallower depth of sediments is always isotopically lighter than that formed in deeper sediments, suggesting the potential application of Mg isotope as a proxy for constraining dolostone formation. [ABSTRACT FROM AUTHOR]

Background/Aims: Vasoconstrictor-induced rhythmic contraction of arteries or veins has been observed both in vivo and in vitro. Many studies have reported that gap junctions, ryanodine receptors, Na+, K+-ATPase and other factors are involved in vasoconstrictor-induced rhythmic contraction in vascular smooth muscle. However, the mechanism is still not completely understood. Methods: We used vessel tension measurements, intracellular recordings and intracellular Cl- concentration ([Cl-]i) measurements to investigate the mechanism underlying phenylephrine (PE)-induced rhythmic contraction in the mouse aorta. Results: We found that Na+-K+-2Cl- cotransporter 1 (NKCC1) inhibitor bumetanide abolished PE-induced rhythmic contraction. The Cl- channel blockers DIDS and niflumic acid initially augmented the amplitude of PE-induced rhythmic contraction but later inhibited the rhythmic contraction. The large Ca2+-activated K+ channel blocker TEA and iberiotoxin increased the amplitude of PE-induced rhythmic contraction. The voltage-dependent Ca2+ channel blocker, nifedipine, and a Ca2+-free solution abolished PE-induced rhythmic contraction. The inhibitor of ryanodine receptors in the sarcoplasmic reticulum, ryanodine, inhibited PE-induced rhythmic contraction. Moreover, bumetanide hyperpolarized the membrane potential of vascular smooth muscle cells in a resting state or after PE pre-treatment. Bumetanide, niflumic acid, ryanodine, iberiotoxin, nifedipine and Ca2+-free buffer significantly suppressed the PE-induced [Cl-]i increase. Conclusion: These data indicate that NKCC1 is involved in the formation of PE-induced rhythmic contraction, and we also provide a method with which to indirectly observe the NKCC1 activity in isolated intact mouse thoracic aortas. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

We have designed, fabricated and characterized an integrated-nanophotonics polarization beamsplitter with a footprint of 2.4 × 2.4 μm2, which is the smallest polarization beamsplitter ever demonstrated. A nonlinear optimization algorithm was used to design the device for λ0 = 1,550 nm. The polarization beamsplitter and the input/output waveguides can be fabricated in a single lithography step. Here, we experimentally show an average transmission efficiency of greater than 70% (peak transmission efficiency of ∼80%) and an extinction ratio greater than 10 dB within a bandwidth of 32 nm. Simulation results indicate that our device is tolerant to fabrication errors of up to ±20 nm in the device thickness. We also designed, fabricated and characterized a mode-converting polarization beamsplitter, which not only separates the two polarization states but also connects one multimode input waveguide to two single-mode output waveguides. [ABSTRACT FROM AUTHOR]

The informatization trend of irrigation area is to master real time hydraulic characteristics of canal sections based on which water distribution can be realized through controlling the gates automatically. In order to serve the information construction of the Shitouhe irrigation area, in this paper, we simulated and analyzed the canal flow and gate opening characteristics with the theory of unsteady flow and automation under different conditions along the 10 km long first reach of east main canal in the Shitouhe irrigation area. In the process of analysis, first of all, the whole canal was divided into several sections, and the sections were numbered from upstream to downstream; then the error of water depth between measured and calculated accordingly was minimized, which was used as the objective function for finding the roughness based on the calculation principle of the water surface curve of the open-channel constant gradual flow; at last we simulated and analyzed the canal flow and gate opening characteristics using different schemes under different boundary conditions and roughness coefficients obtained above. In terms of hydraulic response characteristics analysis under different conditions at canal head, 3 schemes were assumed, which were as follows: Scheme 1, the flow at canal head increased from 3.5 to 11.5 m³/s within 1, 10, 30 and 60 minutes respectively and then remained unchanged Scheme 2, the flow at canal head increased linearly from 3.5 to 5.5, 7.5, 9.5 and 11.5 m³/s within 10 minutes and then remained unchanged; Scheme 3: the flow at canal head varied following the sine curve within 60 minutes and after that remained at 3.5 m³/s unchanged with the maximum variation of 2.5 m³/s. In terms of hydraulic response characteristics analysis under canal water-intake flow, 2 schemes were assumed, and based on these schemes the solutions were: Scheme 1, canal head flow was stable at 3.5, 5.5, 7.5, 9.5 and 11.5 m³/s respectively, and at water intake of No.1 branch (at Section 72) take water according to design flow of 1.03 m³/s; Scheme 2, canal flow was stable at 11.5 m³/s, and at water intake of No.1 branch (Section 72) take water of 0.1, 0.2, 0.4, 0.6, 0.8 and 1.03 m³/s respectively. In terms of hydraulic response characteristics analysis of gate control, 2 schemes were assumed, based on which the solutions were: Scheme 1, the flow at canal head was stable at 11.5 m³/s, and at water intake of No.2 branch take water of 2.5 m³/s under gate control; Scheme 2, the flow at canal head was stable at 11.5 m³/s, at water intake of No.2 branch take water of 2.5 m³/s, and after 2.5 h at water intake of main 7 lateral take water of 0.2 m³/s. Through simulation and analyzation under the different conditions, the hydraulic response characteristics of the canal flow were got as follows: 1) When canal head flow changed, the flow would be changed later with the farther distance from the canal head, and flow along longitudinal direction would be flattened. 2) Under the same flow change rate, the time between starting to change and recovering to be steady would be longer when the distance from canal head was farther, but under different flow change rates, when the flow change rate was larger, the time between starting to change and recovering to be steady would be shorter at the same distance from the canal head. 3) Under different flow rate conditions at canal head, when canal intake flows were the same, the steady flow size exhibited a linear relation with the influence distance of intake flow on upstream stream; but when canal intake flows were different, the steady flow size exhibited an exponential relationship with the influence distance of intake flow on upstream stream. 4) Under steady flow condition at canal head, when individual intake gate was controlled and its opening operates frequently during initial period; when some intake gates were controlled, the opening of any intake gate would affect intake flows of the others, due to the intake flows' reciprocity. 5) By comparison, the simulated hydraulic response characteristics at canal sections were consistent with the measured ones, and the error of canal water depth was within ±10 cm. These may provide some basic knowledge for the safety operation in order to realize scientific allocation of water resources in an irrigation area. [ABSTRACT FROM AUTHOR]

Mechanical forces exerted on cells impose stress on the plasma membrane. Cells sense this stress and elicit a mechanoelectric transduction cascade that initiates compensatory mechanisms. Mechanosensitive ion channels in the plasma membrane are responsible for transducing the mechanical signals to electrical signals. However, the mechanisms underlying channel activation in response to mechanical stress remain incompletely understood. Transient Receptor Potential (TRP) channels serve essential functions in several sensory modalities. These channels can also participate in mechanotransduction by either being autonomously sensitive to mechanical perturbation or by coupling to other mechanosensory components of the cell. Here, we investigated the response of a TRP family member, TRPC5, to mechanical stress. Hypoosmolarity triggers Ca2+ influx and cationic conductance through TRPC5. Importantly, for the first time we were able to record the stretch-activated TRPC5 current at single-channel level. The activation threshold for TRPC5 was found to be 240 mOsm for hypoosmotic stress and between −20 and −40 mmHg for pressure applied to membrane patch. In addition, we found that disruption of actin filaments suppresses TRPC5 response to hypoosmotic stress and patch pipette pressure, but does not prevent the activation of TRPC5 by stretch-independent mechanisms, indicating that actin cytoskeleton is an essential transduction component that confers mechanosensitivity to TRPC5. In summary, our findings establish that TRPC5 can be activated at the single-channel level when mechanical stress on the cell reaches a certain threshold. [ABSTRACT FROM AUTHOR]

Renal fibrosis is the fundamental pathway leading to end-stage renal disease, while its exact molecular basis remains incompletely elucidated. Previous studies have demonstrated that transforming growth factor beta 1 (TGFβ1) is an inducer of the epithelial-to-mesenchymal transition (EMT) of renal tubular epithelial cells, while bone morphogenic protein 7 (BMP7) counteracts TGFβ1-induced EMT and reverses chronic renal injury. Although macrophage recruitment is believed to play an important role during the whole pathogenesis, the mechanism underlying their activate involvement in the formation of renal fibrosis besides phagocytosizing extracellular matrix and apoptotic cells is largely unknown. Here, in a mouse unilateral ureteral obstruction (UUO) model, we show that the recruited macrophages are mainly M1 macrophages at early stage. However, these F4/80-positive and CD301-negative M1 macrophages were shortly polarized into F4/80-positive and CD301-positive M2 macrophages, respectively, which released high levels TGFβ1, to contradict the local expression of BMP7 to facilitate EMT-induced renal fibrosis. M2 macrophages depletion specifically inhibited EMT, and subsequently the renal fibrosis. Adoptive transplantation of M2 macrophages increased the features of renal fibrosis. Our study thus identified double-edged effects of macrophages in the formation of renal fibrosis, which suggest that modulation of macrophage polarization may substantially improve the treatment of renal fibrosis. [ABSTRACT FROM AUTHOR]

Highlights: [•] Stratigraphy of the Proterozoic Huaibei, Huainan, and Feishui groups is described. [•] Chemostratigraphic data are presented and can be correlated with Little Dal Group. [•] Possible vase-shaped microfossils are described from the Huaibei Group. [•] Biostratigraphically useful acritarchs are reported from the Huaibei Group. [•] Integrated stratigraphic data suggest a Tonian age for the Huaibei Group. [Copyright &y& Elsevier]

Chemotherapy is a reasonable alternative to cystectomy in patients with invasive and advanced bladder cancer. However, bladder cancer cells often develop drug resistance to these therapies, and ~ 50% of patients with advanced bladder cancer do not respond to chemotherapy. Recent studies have shown that long non-coding RNA (lnc RNA) is involved in the development of chemoresistance. Here we investigated the role of the urothelial cancer-associated 1 ( UCA1) lnc RNA in cisplatin resistance during chemotherapy for bladder cancer. We showed that cisplatin-based chemotherapy results in up-regulation of UCA1 expression in patients with bladder cancer. Similarly, UCA1 levels are increased in cisplatin-resistant bladder cancer cells. Over-expression of UCA1 significantly increases the cell viability during cisplatin treatment, whereas UCA1 knockdown reduces the cell viability during cisplatin treatment. UCA1 inhibition also partially overcomes drug resistance in cisplatin-resistant T24 cells. Furthermore, we showed that UCA1 positively regulates expression of wingless-type MMTV integration site family member 6 (Wnt6) in human bladder cancer cell lines. UCA1 and Wnt6 expression is also positively correlated in vivo. Up-regulation of UCA1 activates Wnt signaling in a Wnt6-dependent manner. We finally demonstrate that UCA1 increases the cisplatin resistance of bladder cancer cells by enhancing the expression of Wnt6, and thus represents a potential target to overcome chemoresistance in bladder cancer. [ABSTRACT FROM AUTHOR]

Store-operated Ca entry (SOCE) is a common and ubiquitous mechanism regulating Ca influx into cells and participates in numerous biological processes including cell proliferation. Glomerular mesangial cells (GMCs) play a role in the regulation of the glomerular filtration rate. From a clinical point of view, many physiological functions alter with age. In the present study, we used angiotensin II, glucagon, and the sarco/endoplasmic reticulum membrane Ca pump inhibitor thapsigargin to deplete the internal Ca stores for the activation of SOCE. We found that SOCE was significantly attenuated in GMCs from aged (22-month-old) rats. The expression of SOCE-related components, stromal interaction molecule 1 (STIM 1) and Orai 1, in freshly isolated glomeruli notably decreased, and STIM 1 and Orai 1 puncta formation significantly reduced in primary-cultured GMCs in aged rats. Moreover, specific knockdown of STIM 1 and Orai 1 by small interfering RNA markedly suppressed SOCE and cell proliferation of GMCs isolated from young (3-month-old) rats. We conclude that the attenuation of GMCs proliferation can be attributed to the decreased SOCE partially caused by reduced expression of STIM 1 and Orai 1. [ABSTRACT FROM AUTHOR]

Abstract: We measured the magnesium isotopic compositions of endoskarns (i.e., the metasomatically altered interior margin of the pluton) generated by contact metamorphism between granodioritic magma and dolomitic wallrock. The endoskarns were sampled as crustal xenoliths in Pleistocene basaltic cinder cones erupted in eastern California and provide a record of pluton–wallrock interactions at depth. The endoskarns consist of an outer zone made of pyroxenite (Mg-rich) and an inner zone represented by a plagioclase–quartz lithology with relict plutonic textures and minor pyroxene. The inner and outer zones are separated by a thin selvage of phlogopite. The Mg isotopic compositions of these endoskarns are all significantly lighter (δ26Mg<−0.8‰ relative to the Dead Sea magnesium (DSM-3) standard) than canonical peridotitic mantle (δ26Mg=−0.25‰). In particular, the outer pyroxenite zones of the endoskarn are consistently >1‰ lighter (−1.69 to −2.09‰; mean=−1.74‰; SD=0.07‰; n=8) than the mantle, and Mg isotopic values increase in the inner, Mg-poor and plagioclase–quartz dominated zone (δ26Mg of −0.82‰). Because of the high temperatures associated with endoskarn formation, it is unlikely that the light Mg isotopic compositions result from equilibrium isotopic fractionations between mineral phases. The Mg isotopic signatures of the endoskarns are most easily interpreted by the mixing of Mg between Mg-rich and 26Mg-depleted dolomitic wallrock with Mg-poor and 26Mg-enriched magma. Mg isotopes may thus be useful in tracking magma–carbonate interactions in magmas. [Copyright &y& Elsevier]

A series of lanthanide coordination polymers, {[Ln(L)(OX)0.5(H2O)2]·3H2O}n (Ln = La 1, and Ce 2), [Ln2(L)2(OX)(H2O)3]n (Ln = Pr 3, Nd 4, Sm 5, Eu 6, Gd 7, Tb 8, Dy 9, Er 10, and Yb 11) (H2L = (3-(4-hydroxypyridinium-1-yl) phthalic acid, H2OX = oxalic acid), have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction. The title compounds are crystallized in the same triclinic space group P1̅ but display different 2D layer structures with different dinuclear secondary building units (SBUs) due to the effect of lanthanide contraction. Furthermore, X-ray diffraction and thermogravimetric analysis of 1–11 are also studied, which demonstrate their high purities and good thermal stabilities. Luminescent measurements indicate that the Eu (6), Tb (8), and Dy (9) compounds exhibit ligand (L2−) sensitized emissions in red, green, and yellow light regions, respectively. [ABSTRACT FROM AUTHOR]

• A liquid chromatography-ion mobility-mass spectrometry method was established. • A 2-step filtering strategy integrated CCS interval predicting and MDF was developed. • Power regression was used to generate the CCS interval with 99% confidence level. • Totally, 172 isoquinoline alkaloid analogues were identified in four herbal samples. • False positive rates of integrated 2-step filtering and common MDF were compared. Rapid identification of chemical analogues in herbal medicines using liquid chromatography-mass spectrometry was an efficient tool for discoveries of potentially active ingredients. Multi-dimensional combination of various separation technologies could significantly enhance the capacities for detection of trace components and discrimination of multiple isomers. In this study, an integrated two-step filtering strategy on liquid chromatography-ion mobility tandem with quadrupole-time-of-flight mass spectrometry (LC-IM-QTOF MS) was developed for identification of analogues in complex matrixes. The extracted raw data were preliminarily filtered by a collision-cross section (CCS) interval generated from power regression with confidence level at 99% for prediction of analogues. Then, the remained ions were further screened using a mass defect filtering (MDF) window based on m/z and decimal m/z of potential skeletons and substituents. By applying this strategy, 86, 102, 73, and 57 isoquinoline alkaloids were identified in herbal materials of Coptis chinensis Franch (CC), C. deltoidea C.Y.Cheng et Hsiao (CD), C. teeta Wall (CT), and Corydalis yanhusuo W.T.Wang (CY). The integrated two-step filtering presented higher efficiencies on exclusion of the background interference and reducing the false-positive rates than previously reported approaches. This study facilitated the application of LC-IM-MS on small molecular analysis and promoted the discoveries of bioactive components of herbal medicines for further pharmacological researches and quality control. [ABSTRACT FROM AUTHOR]

This study presents a method to accurately model soil salinity using statistical tools. The method integrates field data, geographic information systems, remote sensing, and spatial modeling. Kriging analysis for topsoil salinity distribution in the study area indicates that soil salinity has a strong degree of autocorrelation (C0/(C0+C)=15.93) and low variability (CV=5.5%). The coefficient of determination (R2) for the predicted soil salinity is 0.867. The predicted salinity of the topsoil is higher than that in the deep soil, although both salinity distributions show a similar trend. This study provides timely understanding of soil reclamation efforts and local water management practice. [ABSTRACT FROM PUBLISHER]

A snake venom thrombin-like enzyme (SVTLE) from Agkistrodon halys pallas venom was isolated by means of a two-step chromatographic procedure. The purified enzyme, named AhV_TL-I, showed fibrinogenolytic activity against both the Aα and Bβ chains of bovine fibrinogen. Unlike the other SVTLEs, AhV_TL-I has poor esterolytic activity upon BAEE substrate. The N-terminal sequence of AhV_TL-I was determined to be IIGGDEXNINEHRFLVALYT, and the molecular mass was confirmed to 29389.533 Da by MALDI-TOF mass spectrometry. Its complete cDNA and derived amino acid sequence were obtained by RT-PCR. The crystal structure of AhV_TL-I was determined at a resolution of 1.75 Å. A disaccharide was clearly mapped in the structure, which involved in regulating the esterolytic activity of AhV_TL-I. The presence of the N-glycan deformed the 99-loop, and the resulting steric hindrances hindered the substrates to access the active site. Furthermore, with the carbohydrate moiety, AhV_TL-I could induce mouse thoracic aortic ring contraction with the EC of 147 nmol/L. Besides, the vasoconstrictor effects of AhV_TL-I were also independent of the enzymatic activity. The results of [Ca] measurement showed that the vasoconstrictor effects of AhV_TL-I were attributed to Ca releasing from Ca store. Further studies showed that it was related to the activation of ryanodine receptors (RyRs). These offer new insights into the snake SVTLEs functions and provide a novel pathogenesis of A. halys pallas venom. [ABSTRACT FROM AUTHOR]

Let H be a finite-dimensional Hopf algebra, let A be a finite-dimensional algebra measured by H, and let A # H be a crossed product. In this paper, we first show that if H is semisimple as well as its dual H*, then the complexity of A # H is equal to that of A. Furthermore, we prove that the complexity of a finite-dimensional Hopf algebra H is equal to the complexity of the trivial module k. As an application, we prove that the complexity of Sweedler's 4-dimensional Hopf algebra H is equal to 1. [ABSTRACT FROM AUTHOR]

The Cretaceous to early Paleogene (ca. 140-50 Ma) was characterized by a greenhouse baseline climate, driven by elevated concentrations of atmospheric CO2. Hypotheses for the elevated CO2 concentrations invoke an increase in volcanic CO2 production due to higher oceanic crust production rates, higher frequency of large igneous provinces, or increases in pelagic carbonate deposition, the last leading to enhanced carbonate subduction into the mantle source regions of arc volcanoes. However, these are not the only volcanic sources of CO2 during this time interval. We show here that ocean-continent subduction zones, manifested as a global chain of continental arc volcanoes, were as much as 200% longer in the Cretaceous and early Paleogene than in the late Paleogene to present, when a cooler climate prevailed. In particular, many of these continental arcs, unlike island arcs, intersected ancient continental platform carbonates stored on the continental upper plate. We show that the greater length of Cretaceous-Paleogene continental arcs, specifically carbonate-intersecting arcs, could have increased global production of CO2 by at least 3.7-5.5 times that of the present day. This magmatically driven crustal decarbonation flux of CO2 through continental arcs exceeds that delivered by Cretaceous oceanic crust production, and was sufficient to drive Cretaceous-Paleogene greenhouse conditions. Thus, carbonate-intersecting continental arc volcanoes likely played an important role in driving greenhouse conditions in the Cretaceous-Paleogene. If so, the waning of North American and Eurasian continental arcs in the Late Cretaceous to early Paleogene, followed by a fundamental shift in western Pacific subduction zones ca. 52 Ma to an island arc-dominated regime, would have been manifested as a decline in global volcanic CO2 production, prompting a return to an icehouse baseline in the Neogene. Our analysis leads us to speculate that long-term (>50 m.y.) greenhouse-icehouse oscillations may be linked to fluctuations between continental- and island arc-dominated states. These tectonic fluctuations may result from large-scale changes in the nature of subduction zones, changes we speculate may be tied to the assembly and dispersal of continents. Specifically, dispersal of continents may drive the leading edge of continents to override subduction zones, resulting in continental arc volcanism, whereas assembly of continents or closing of large ocean basins may be manifested as large-scale slab rollback, resulting in the development of intraoceanic volcanic arcs. We suggest that greenhouse-icehouse oscillations are a natural consequence of plate tectonics operating in the presence of continental masses, serving as a large capacitor of carbonates that can be episodically purged during global flare-ups in continental arcs. Importantly, if the global crustal carbonate reservoir has grown with time, as might be expected because platform carbonates on continents do not generally subduct, the greenhouse-driving potential of continental arcs would have been small during the Archean, but would have increased in the Neoproterozoic and Phanerozoic after a significant reservoir of crustal carbonates had formed in response to the evolution of life and the growth of continents. [ABSTRACT FROM AUTHOR]

Key points Activation of afferents in the posterior femoral cutaneous nerve (PFCN) can reflexively induce efferent firing in the pudendal nerve and pudendal afferent firing via a motor-sensory coupling., Activation of pudendal afferent nerves can inhibit the micturition reflex, suggesting PFCN stimulation might also inhibit the micturition reflex., This study discovered a somato-bladder inhibitory reflex elicited by electrical or tactile stimulation of cutaneous afferents in the PFCN, but excluded the involvement of pudendal nerves., This PFCN-bladder inhibitory reflex could be utilized to develop new neuromodulation therapies for lower urinary tract disorders., Abstract This study determined if activation of somatic afferents in posterior femoral cutaneous nerve (PFCN) could modulate the micturition reflex recorded under isovolumetric conditions in α-chloralose anaesthetized cats. PFCN stimulation inhibited reflex bladder activity and significantly ( P < 0.05) increased bladder capacity during slow infusion of saline or 0.25% acetic acid (AA). The optimal frequency for PFCN stimulation-induced bladder inhibition was between 3 and 10 Hz, and a minimal stimulation intensity of half of the threshold for inducing anal twitching was required. Bilateral pudendal nerve transection eliminated PFCN stimulation-induced anal twitching but did not change the stimulation-induced bladder inhibition, excluding the involvement of pudendal afferent or efferent axons in PFCN afferent inhibition. Mechanical or electrical stimulation on the skin surface in the PFCN dermatome also inhibited bladder activity. Prolonged (2 × 30 min) PFCN stimulation induced a post-stimulation inhibition that persists for at least 2 h. This study revealed a new cutaneous-bladder reflex activated by PFCN afferents. Although the mechanisms and physiological functions of this cutaneous-bladder reflex need to be further studied, our data raise the possibility that stimulation of PFCN afferents might be useful clinically for the treatment of overactive bladder symptoms. [ABSTRACT FROM AUTHOR]

Abstract: A new bifunctional ligand (IA-PEG-DTC), poly(ethylene glycol) (PEG) appended dithiocarbamate derived from iminodiacetic acid, has been designed and synthesized. The obtained IA-PEG-DTC ligand with the dithiocarbamate group strongly bonding to the surface atom of quantum dots (QDs), the PEG segment rendering QDs water-soluble, and the free carboxylic group available for further bioconjugation was used successfully to transfer initial oil-soluble QDs into water-soluble ones. The resulting IA-PEG-DTC capped water-soluble QDs have relatively small hydrodynamic size, and importantly, retain high fluorescence quantum yield of the original hydrophobic QDs. In addition, the obtained water-soluble QDs exhibit excellent colloidal stability under conditions of wide pH range (2–13), long-term UV-irradiation, the boiling state, and high salt concentrations. These results indicate that the water-soluble QDs coated by the bifunctional IA-PEG-DTC ligand have potential for applications in cellular imaging and biosensor. [Copyright &y& Elsevier]

Low temperature specific heat has been measured in optimally doped and highly overdoped nonsuperconducting Ba(Fe1-xTMx)2 As2 (TM = Co and Ni) single crystals. By using the data of the overdoped samples, we successfully removed the phonon contribution of the optimally doped ones, and derived the electronic specific heat coefficient ye. Remarkably, we found a continuing temperature dependent &ggr;e(T) which follows the quadratic relation &ggr;e = &ggr;0 + αT2 in the low temperature limit. Together with the very small residual term &ggr;0, linear magnetic field dependence of &ggr;e, it is concluded that there are either small segments of nodal lines, or pointlike nodes in these samples. [ABSTRACT FROM AUTHOR]

The notion of a crossed product with a Hopf algebroid was introduced by Böhm and Brzeziński [12]. It is well-known that weak Hopf algebras (see Böhm et al. [10]) is an example of Hopf algebroids. Then we get the definition and some property of a weak crossed product A#σ H over an algebra A and a weak Hopf algebra H. Next we give a Maschke-type theorem for the weak crossed product over a semisimple weak Hopf algebra H. Furthermore, we obtain an analogue of the Nikshych's duality theorem for weak crossed products. Finally, using this duality theorem, we prove that the global dimension of A equals to the global dimension of A#σ H if H and H* are both semisimple. [ABSTRACT FROM PUBLISHER]

What's known on the subject? and What does the study add? It is known that direct stimulation of pudenal nerve using a cuff electrode can inhibit normal bladder activity. This study further indicates that overactive bladder activity can be inhibited using non-invasive skin surface electrodes and a transdermal amplitude-modulated signal (TAMS). OBJECTIVE [ABSTRACT FROM AUTHOR]

Abstract: In order to understand spatial variations of stable isotope geochemistry in the Quruqtagh basin (northwestern China) in the aftermath of an Ediacaran glaciation, we analyzed carbonate carbon isotopes (δ 13 C carb), carbonate oxygen isotopes (δ 18 O carb), carbonate associated sulfate sulfur (δ 34 S CAS) and oxygen isotopes (δ 18 O CAS), and pyrite sulfur isotopes (δ 34 S py) of a cap dolostone atop the Ediacaran Hankalchough glacial diamictite at four sections. The four studied sections (YKG, MK, H and ZBS) represent an onshore–offshore transect in the Quruqtagh basin. Our data show a strong paleobathymetry-dependent isotopic gradient. From the onshore to offshore sections, δ 13 C carb values decrease from −2‰ to −16‰ (VPDB), whereas δ 18 O carb values increase from −4‰ to −1‰ (VPDB). Both δ 34 S CAS and δ 34 S py show stratigraphic variations in the two onshore sections (MK and YKG), but are more stable in the two offshore sections (H and ZBS). δ 18 O CAS values of onshore samples are consistent with terrestrial oxidative weathering of pyrite. We propose that following the Hankalchough glaciation seawater in the Quruqtagh basin was characterized by a strong isotopic gradient. The isotopic data may be interpreted using a three-component mixing model that involves three reservoirs: deep-basin water, surface water, and terrestrial weathering input. In this model, the negative δ 13 C carb values in the offshore sections are related to the upwelling of deep-basin water (where anaerobic oxidation of dissolved organic carbon resulted in 13 C-depleted DIC), whereas sulfur isotope variations are strongly controlled by surface water sulfate and terrestrial weathering input derived from oxidative weathering of pyrite. The new data provide evidence for the oceanic oxidation following the Hankalchough glaciation. [Copyright &y& Elsevier]

Abstract: Germanium/silica (Ge/Si) ratios of dolostone- and mudstone-hosted chert nodules from the Ediacaran (635–542Ma) Doushantuo Formation in the Yangtze Gorges area, South China, are reported. These chert nodules typically have a calcite rim, a pyrite rim, and a silica core, the latter sometimes containing disseminated pyrite. The silica core was precipitated by early diagenetic replacement of carbonate and silty/muddy sediments. Two types of chert nodules are identified based on their mineralogy and geochemistry. Type-1 chert nodules are poor in disseminated pyrite in the silica core. They also have low Al, and show a strong positive correlation between Al contents and Ge/Si with a near-zero or negative intercept. In contrast, Type-2 chert nodules contain abundant disseminated pyrite in the silica core and show a weakly positive correlation between Ge/Si ratios and Al contents (with a large positive intercept on the Ge/Si axis). The Ge/Si of Doushantuo nodules are greater than those of Cretaceous deep-sea cherts, suggesting that the Ge/Si ratio of Ediacaran seawater/porewater was greater than the Cretaceous due to the more effective discrimination against Ge by inorganic opal precipitation relative to biogenic opal precipitation. The positive correlation between Ge/Si and Al can be interpreted using a mixing model with a pure chert (characterized by a low Ge/Si ratio) and an Al-rich endmember (characterized by a high Ge/Si ratio). The latter is most likely represented by a clay component, but the model-based estimate of the Ge/Si ratio inferred for the Al-rich (clay) endmember is much higher than that of Phanerozoic clay minerals. These high Ge/Si ratios for the clay endmember may be related to the generally high Ge/Si ratio of Ediacaran seawater, but could also be related to clay–organic matter interactions. Organic matter absorbed to clays could provide an additional source of Ge because certain organic molecules are known to have a high affinity for Ge due to their strong metal ion-chelating properties. The high Ge/Si ratio of the Al-rich endmember in Type-1 chert nodules suggests that Ge in porewaters from which these cherts precipitated may have been dominated by Ge–organic complexes. The low Ge/Si ratio inferred for the Al-rich endmember in Type-2 chert nodules is therefore taken to indicate that Ge was released from organic matter, perhaps due to anaerobic degradation of organic matter (accompanied by the formation of pyrite), and was redistributed between clay–organic endmembers and pure chert, resulting in a non-zero intercept in the Ge/Si vs. Al2O3 plots. These observations suggest that a strong terrestrial influence in a restricted sedimentary basin or a high content of dissolved organic carbon in Ediacaran seawater and porewater may have contributed to the dominance of Ge–organic complexes in the Doushantuo basin in the Yangtze Gorges area. [Copyright &y& Elsevier]

Background: To evaluate the experience of induction chemotherapy followed by concurrent chemoradiationwith helical tomotherapy (HT) for nasopharyngeal carcinoma (NPC).Methods: Between August 2006 and December 2009, 28 patients with pathological proven nonmetastatic NPC were enrolled. All patients were staged as IIB-IVB. Patients were first treated with 2 to 3 cycles of induction chemotherapy with EP-HDFL (Epirubicin, Cisplatin, 5-FU, and Leucovorin). After induction chemotherapy, weekly based PFL was administered concurrent with HT. Radiation consisted of 70 Gy to the planning target volumes of the primary tumor plus any positive nodal disease using 2 Gy per fraction.Results: After completion of induction chemotherapy, the response rates for primary and nodal disease were 96.4% and 80.8%, respectively. With a median follow-up after 33 months (Range, 13-53 months), there have been 2 primary and 1 nodal relapse after completion of radiotherapy. The estimated 3-year progression-free rates for local, regional, locoregional and distant metastasis survival rate were 92.4%, 95.7%, 88.4%, and 78.0%, respectively. The estimated 3-year overall survival was 83.5%. Acute grade 3, 4 toxicities for xerostomia and dermatitis were only 3.6% and 10.7%, respectively.Conclusion: HT for locoregionally advanced NPC is feasible and effective in regard to locoregional control with high compliance, even after neoadjuvant chemotherapy. None of out-field or marginal failure noted in the current study confirms the potential benefits of treating NPC patients by image-guided radiation modality. A long-term follow-up study is needed to confirm these preliminary findings. [ABSTRACT FROM AUTHOR]

Abstract: To determine the involvement of opioid receptors in the inhibitory pudendal-to-bladder reflex, the effect of naloxone (0.01–1mg/kg, i.v.), an opioid receptor antagonist, on the inhibition of bladder activity evoked by pudendal nerve stimulation was investigated in α-chloralose anesthetized cats. The inhibition of reflex isovolumetric bladder contractions induced by pudendal nerve stimulation (5–10Hz) at intensity threshold (T) for producing complete inhibition was significantly suppressed by naloxone at a high dose (0.3mg/kg). However, the inhibition elicited at higher intensities (1.5–3T) was not changed. Naloxone (1mg/kg) did not alter the frequency dependence of the inhibitory effect of pudendal stimulation. During cystometrograms (CMGs) pudendal nerve stimulation significantly increased bladder capacity to 155.1±24.5% and 163.4±10% of the control at stimulation intensities of 1T and 1.5–3T, respectively. After administration of naloxone (1mg/kg), the bladder capacity during pudendal nerve stimulation at inhibition threshold (1T) was not significantly different from control, but it was significantly increased at higher intensities (1.5–3T). Naloxone alone markedly reduced bladder capacity to 43±11.1% of the control, and pudendal stimulation completely reversed this facilitatory effect. This study revealed that activation of opioid receptors contributes to or facilitates the inhibitory pudendal-to-bladder reflex. The reduction in bladder capacity after naloxone treatment also indicates that endogenous opioid peptides mediate a tonic inhibition of micturition. Understanding the neurotransmitter mechanisms involved in the inhibitory pudendal-to-bladder reflex could promote the development of new treatments for bladder overactivity and incontinence. [Copyright &y& Elsevier]