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Carbon fiber–reinforced polymer (CFRP) composites are widely utilized in the aerospace industry due to their exceptional mechanical properties. In this paper, a regular dodecagon trajectory side milling method was employed to investigate the high-speed cutting performance of CFRP, focusing on the impact of fiber cutting angle, up milling and down milling, processing parameters, and cooling conditions on the cutting characteristics. Results indicate that utilizing the Gr-NMQL cutting lubrication method can significantly improve machining surface quality while reducing cutting force by up to 15%. Additionally, using a PCD burr milling cutter, the normal and tangential cutting forces followed a particular trend: 60° > 30° > 90° > 0° > 150° > 120°. Moreover, when the cutting speed exceeded 200m/min, both normal and tangential cutting forces showed a significant decrease. Cutting along the fiber direction yielded superior machining quality compared to it, and the optimal surface roughness was achieved when cutting along the 90° direction. Finally, a comparative study of up milling and down milling revealed that implementing the up milling process improved both cutting force and surface quality. These findings contribute to a deeper understanding of the high-speed milling performance of CFRP and provide insights for optimizing the machining process. [ABSTRACT FROM AUTHOR]

Deep-holes are typical parts of aircraft structures, which is difficult to be machined. Boring assisted with ultrasonic vibration-assisted cutting has been proved to greatly enhance machining performance, especially for Ti6Al4V aviation alloy. This paper focuses on the machining extra-large aspect ratio (exceeding 20) of Ti6Al4V aviation deep-hole with the axial ultrasonic vibration-assisted boring (AUVB) method. First, the kinetics of the AUVB process is analyzed and a retrospective of its separation cutting feature is provided. Subsequently, a multi-stepped cantilever beam model of boring bar is established to analyze its static rigidity and dynamic stability. The aperture error is deduced, and then size coefficient is put forward to represent the static rigidity of the boring bar, which is inversely proportional to the diameter. In addition, two different vibration cases, namely modal-coupling vibration and regenerative vibration are considered for dynamic stability analysis. Next, the morphology of bored surface is analyzed, and the geometric height of peaks formed by AUVB and CB are calculated. Phase shift φ= π is suggested for obtaining a better surface in AUVB. Finally, the feasibility of AUVB on the machining of extra-large aspect ratio Ti6Al4V titanium alloy aviation deep-hole is verified through systematic experiments. Results demonstrate that AUVB has obvious advantages in reducing boring force, improving boring accuracy, suppressing vibration and promoting surface quality. Furthermore, the aperture error decreases to 50% and vibration amplitudes decrease to only 20–25%. The overall surface roughness of the deep-hole part stays below Ra=0.8μm with rotational speeds of 60r/min and 80r/min, and the surface residual stress state is transferred from the tensile state to a compressive one. As a result, not only AUVB can provide better boring accuracy and surface finish, but it also can enhance the surface fatigue properties. [ABSTRACT FROM AUTHOR]

Bupivacaine (BUP) is a long-acting amide local anesthetic that may induce strong neurotoxicity and neurological complications. In this study, we elucidate the influence of microRNA-494-3p (miR-494-3p) in BUP-induced neurotoxicity in primary mouse hippocampal neuronal cells. In this study, primary hippocampal neurons were isolated from neonatal C57BL/6 mice. The isolated neurons were treated with various doses of BUP. MTT assay was conducted to analyze neuronal viability. Gene expression measurement was done by RT-qPCR. The impact of miR-494-3p in BUP-mediated neural injury was examined using TUNEL, flow cytometry, western blotting, and ROS activity detection. The regulatory relationship between miR-494-3p and cyclin-dependent kinases 4 and 6 (CDK6) was identified using a luciferase reporter assay. BUP treatment led to neurotoxicity and miR-494-3p upregulation in primary cultured hippocampal neurons. Functionally, miR-494-3p depletion alleviated neuronal apoptosis and oxidative damage induced by BUP. We verified that miR-494-3p targeted and negatively modulated CDK6. MiR-494-3p depletion also activated PI3K/AKT signaling by elevating CDK6 expression in BUP-treated neurons. Furthermore, CDK6 knockdown or PI3K/AKT inactivation attenuated the neuroprotective role of miR-494-3p depletion. Silencing miR-494-3p exerts neuroprotective function in hippocampal neuronal cells against BUP-induced injury by the CDK6-PI3K/AKT pathway. [ABSTRACT FROM AUTHOR]

Axial ultrasonic vibration-assisted cutting (AUVC) has been proved to have better machining performance compared with conventional cutting methods; however, the effect of numerous and complex influencing factors on machining performance has not been clearly revealed, and a recommended combination of cutting conditions has not been proposed yet, especially for difficult-to-machine material such as Ti6Al4V alloy. This paper focuses on the experimental and theoretical investigation into Ti6Al4V machining performance with AUVC method. First, a retrospective of the separation characteristics of AUVC is provided, and the variable parameter cutting characteristics are demonstrated. The influencing factors on machining performance are classified into four categories: machining parameters, vibration parameters, tool choice, and cooling conditions. The relationship between these factors in terms of their effect on machining performance is established theoretically. Then, it describes experiments to determine the influence of these factors on cutting force, tool life, and surface roughness. For absolute influence, the orders for cutting force, tool life, and surface roughness are respectively cutting depth > amplitude > feed rate > rotation speed, rotation speed > feed rate > amplitude > cutting depth, and feed rate > amplitude > cutting depth > rotation speed. However, for relative influence, the order is unified as amplitude > feed rate > rotation speed > cutting depth. Finally, it suggests a smaller feed rate, larger amplitude, moderate rotation speed, and smaller cutting depth in addition to a WC tool coated with TiAlN and used under HPC cooling condition for optimal performance of AUVC. This recommendation is based on the theoretical analysis and experimental results of cutting force, surface roughness, and tool life. [ABSTRACT FROM AUTHOR]

The scale-dependent predictability of the devastating 7·20 extreme rainstorm in Zhengzhou, China in 2021 was investigated via ensemble experiments, which were perturbed on different scales using the stochastic kinetic-energy backscatter (SKEB) scheme in the WRF model, with the innermost domain having a 3-km grid spacing. The daily rainfall (RAIN24h) and the cloudburst during 1600–1700 LST (RAIN1h) were considered. Results demonstrated that with larger perturbation scales, the ensemble spread for the rainfall maximum widens and rainfall forecasts become closer to the observations. In ensembles with mesoscale or convective-scale perturbations, RAIN1h loses predictability at scales smaller than 20 km and RAIN24h is predictable for all scales. Whereas in ensembles with synoptic-scale perturbations, the largest scale of predictability loss extends to 60 km for both RAIN1h and RAIN24h. Moreover, the average positional error in forecasting the heaviest rainfall for RAIN24h (RAIN1h) was 400 km (50–60) km. The southerly low-level jet near Zhengzhou was assumed to be directly responsible for the forecast uncertainty of RAIN1h. The rapid intensification in low-level cyclonic vorticity, mid-level divergence, and upward motion concomitant with the jet dynamically facilitated the cloudburst. Further analysis of the divergent, rotational and vertical kinetic spectra and the corresponding error spectra showed that the error kinetic energy at smaller scales grows faster than that at larger scales and saturates more quickly in all experiments. Larger-scale perturbations not only boost larger-scale error growth but are also conducive to error growth at all scales through a downscale cascade, which indicates that improving the accuracy of larger-scale flow forecast may discernibly contributes to the forecast of cloudburst intensity and position. [ABSTRACT FROM AUTHOR]

Axial ultrasonic vibration–assisted cutting has been proposed and proved preponderance on cutting performance; however, the transient separation cutting characteristic has not been clearly revealed. This paper focuses on the transient separation cutting characteristic of axial ultrasonic vibration–assisted cutting and its influence on the cutting performance. First, the separation cutting criteria, including feed coefficient and phase shift, are established and influence factors, such as feed rate, amplitude, and phase shift, are systematically analyzed. Subsequently, the duty ratio is deduced and calculated, and some features and a control mechanism are introduced. In addition, a transient separation cutting model with four stages is demonstrated. The reason for the average cutting force reduction by the transient separation cutting characteristic is also stated. Finally, the verification of the separation cutting and transient separation cutting model and the comparison of the feed thrust force and parameter influences on the cutting performance are experimentally performed. The transient signals of different duty ratios 0.55 to 1 are obtained, and 10 to 40% reductions of feed thrust are measured both by a PCB sensor and a Kistler dynamometer. The influence degree of the feed coefficient, spindle rotation speed, and cutting depth on the performance is analyzed. A parameter combination of smaller feed coefficient, moderate spindle rotation speed, and smaller cutting depth is suggested to obtain a better cutting performance by fully considering the cutting force, surface roughness, and tool life. [ABSTRACT FROM AUTHOR]

Three-dimensional Hashin failure criterion and material stiffness degradation model were compiled by VUMAT subroutine. The Abaqus/Explicit solver was performed to establish progressive damage model of cutting force for CFRP high-speed milling, and high-speed milling experiments with different cutting parameters were carried out. Further, the impact mechanism of fiber cutting angle and cutting parameters on cutting force, stress, and material failure during milling was explored, and the material removal mechanism in high-speed milling of CFRP was revealed. The results show that the error between the experimental and simulated of cutting forces is less than 5%, which indicates that the progressive damage model is feasible. The fiber cutting angle has significant influence on cutting force and stress in cutting process, and the cutting direction has a significant influence on cutting force. In addition, cutting parameters play a critical role in cutting force, and the feed per tooth is the most significant factor affecting the cutting force. Simultaneously, the progressive damage model predicts that the shear failure of materials mainly concentrates in the cutting area and extends along the feed direction. Finally, the material removal mechanism of CFRP in high-speed milling was revealed combining cutting force experiment. [ABSTRACT FROM AUTHOR]

Based on our previous study (Yu et al., Clim Dyn 49:1139-1156, 2017), this paper further investigates the interdecadal change in the relationship between the Kuroshio Extension (KE; 27°-37°N, 140°-158°E) and the East Asian summer monsoon (EASM) in the late 1980s. The summer KE sea surface temperature anomalies (SSTAs) show a significant positive relationship with the EASM over the period 1968-1987 (P1), but a significant negative connection with the EASM between 1991 and 2010 (P2). This interdecadal change in the KE-EASM relationship can be interpreted by considering the difference in the relationships of summer KE SSTAs with the East Asian subtropical westerly jet (EASWJ) and western North Pacific subtropical high (WNPSH) during the two periods. During P1, summertime KE SST warming is significantly related to the strengthened EASWJ and WNPSH, but it has close relationships with the weakened and northward-moving EASWJ and WNPSH during P2. These anomalous EASWJ and WNPSH associated with the summertime KE SST warming in P1 (P2) then favors increased (reduced) rainfall over the Yangtze River Valley that corresponds to a strong (weak) EASM, thereby leading to the significant positive (negative) KE-EASM relationship during this period. This change in the relationships of summer KE SSTAs with the EASWJ and WNPSH may be attributed to the increased KE SST variability associated with an enhanced Pacific Decadal Oscillation (PDO) in summer during P2, which is most probably induced by the stronger North Pacific Oscillation (NPO)-like atmospheric forcing, especially its southern pole (SP), in the preceding spring during this period. The spring NPO-like SP forces the KE SSTAs and PDO more directly during the following summer and can thus have been a better precursor for the following EASM than the full NPO-like dipole after the late 1980s. [ABSTRACT FROM AUTHOR]

In this study, the nonlinear local Lyapunov exponent (NLLE) approach was used to quantitatively determine the predictability limit of tropical cyclone (TC) tracks based on observed TC track data obtained from the Joint Typhoon Warning Center. The results show that the predictability limit of all TC tracks over the whole western North Pacific (WNP) basin is about 102 h, and the average lifetime of all TC tracks is about 174 h. The predictability limits of the TC tracks for short-, medium-, and long-lived TCs are approximately 72 h, 120 h, and 132 h, respectively. The predictability limit of the TC tracks depends on the TC genesis location, lifetime, and intensity, and further analysis indicated that these three metrics are closely related. The more intense and longer-lived TCs tend to be generated on the eastern side of the WNP (EWNP), whereas the weaker and shorter-lived TCs tend to form in the west of the WNP (WWNP) and the South China Sea (SCS). The relatively stronger and longer-lived TCs, which are generated mainly in the EWNP, have a longer travel time before they curve northeastwards and hence tend to be more predictable than the relatively weaker and shorter-lived TCs that form in the WWNP region and SCS. Furthermore, the results show that the predictability limit of the TC tracks obtained from the best-track data may be underestimated due to the relatively short observational records currently available. Further work is needed, employing a numerical model to assess the predictability of TC tracks. [ABSTRACT FROM AUTHOR]

Lithium iron(II) phosphate (LiFePO) particles were simultaneously modified via reduced graphene oxide (rGO) and manganese ion(II) (Mn) through a facile one-step method. X-ray photoelectron spectroscopy unravels that the formation of Mn-O bond originated from Mn ion and fringe oxygen atoms of LiFePO, which is beneficial for the rate capability of cathode. As cathode for lithium-ion battery, the as-prepared rGO/Mn-LiFePO composite exhibits excellent electrochemical properties. Its discharge-specific capacity is 159 mAh g at 1 C after 800 cycles with capacity retention of 92%. Even at a high rate of 10 C, the rGO/Mn-LiFePO composite is still capable of delivering 140 mAh g of discharge-specific capacity, indicating its excellent rate capability and cycle stability. It was demonstrated that the simultaneous modification of Mn and rGO does not destroy the olivine structure of LiFePO, but it can stabilize the crystal structure, decrease the electrode polarization, enhance the electronic conductivity and Li diffusion coefficient, and thus improve its cycling and high-rate capability. [ABSTRACT FROM AUTHOR]

This study reveals that the relationship between the western North Pacific Ocean (WNPO; 0-55°N, 100-165°E) and the East Asian summer monsoon (EASM) experiences a well-defined interdecadal change in the late 1980s and early 1990s. The EASM-related WNPO sea surface temperature anomaly (SSTA) pattern changes from the dipole pattern [WNPO dipole (WNPOD)] that develops over the period between 1968 and 1987 (P1) to a tripole pattern [WNPO tripole (WNPOT)] between 1991 and 2010 (P2). The positive (negative) phase of the WNPOD is characterized by warm (cold) SSTAs in the Japan Sea and Kuroshio-Oyashio Extension region, and cold (warm) SSTAs in the subtropical WNPO, whereas the positive (negative) phase of the WNPOT shows warming (cooling) in the Kuroshio Extension region (KER), and cooling (warming) in the south of Kamchatka Peninsula (SKP) and Philippine Sea (PS). During P1 (P2), the WNPOD (WNPOT) can be regarded as the first (second) leading mode of summer WNPO SST variability, and its positive phase is associated with a weakened WNPO subtropical high and thereby the deficient summer rainfall in the Yangtze River valley, together with a strong EASM, and vice versa. The change in the WNPO-EASM relationship may be caused by interdecadal changes in the relationship of the equatorial central Pacific (ECP) with the WNPO and EASM, and an increase in summer KER SST variability. During P2, because the ECP warming-induced cyclonic anomalies move northwestwards and intensify, summertime ECP warming is able to generate a strong EASM and significant cooling over the two poles of the WNPOT (SKP and PS). These strengthened impacts of the ECP on the WNPOT and EASM contribute to the strengthened WNPOT-EASM relationship during P2. In addition, summer KER SST variability increases between 1991 and 2010, and this may have enhanced the impact of the KER on the EASM during P2. These two factors probably cause the EASM-related WNPO SSTA pattern to change from the WNPOD in P1 to the WNPOT in P2. [ABSTRACT FROM AUTHOR]

Based on the theory of information entropy concerning nonlinear errors, the growth rules for the nonlinear errors of the Lorenz system and its predictable components are studied. The results show that the impact of the uncertainties, both in the initial error and in the system itself, needs to be considered in a quantitative estimation of the system predictability. The nonlinear error growth is related to the magnitude of the initial error, and to the spatial distribution of the initial error vectors. Even if these initial errors have the same magnitude but different directions, there are also differences in the nonlinear error growth. The predictability of nonlinear error growth is related to the error component, but not related to the ratio of these components. The component with the highest/lowest rate of contribution does not necessarily have the greatest/least predictability. The different components have different predictabilities, and in different time periods, the different predictable components also have different predictabilities. [ABSTRACT FROM AUTHOR]

Lactate dehydrogenase A (LDHA) is the enzyme that converts pyruvate to lactate and oxidizes the reduced form of nicotinamide adenine dinucleotide to NAD. Several human cancers including the pancreas display elevated expression of LDHA. Because of its essential role in cancer metabolism, LDHA has been considered to be a potential target for cancer therapy. Recently, we have shown that a green tea extract significantly down-regulated LDHA in HPAF-II pancreatic cancer cells using global proteomics profiling. The present study is to investigate how EGCG, a major biological active constituent of green tea, targets the metabolism of human pancreatic adenocarcinoma MIA PaCa-2 cells. We compared the effect of EGCG to that of oxamate, an inhibitor of LDHA, on the multiple metabolic pathways as measured by extracellular lactate production, glucose consumption, as well as intracellular aspartate and glutamate production, fatty acid synthesis, acetyl-CoA, RNA ribose and deoxyribose. Specific metabolic pathways were studied using [1, 2-C]- d-glucose as the single precursor metabolic tracer. Isotope incorporations in metabolites were analyzed using gas chromatography/mass spectrometry (GC/MS) and stable isotope-based dynamic metabolic profiling (SiDMAP). We found that the EGCG treatment of MIA PaCa-2 cells significantly reduced lactate production, anaerobic glycolysis, glucose consumption and glycolytic rate that are comparable to the inhibition of LDHA by oxamate treatment. Significant changes in intracellular glucose carbon re-distribution among major glucose-utilizing macromolecule biosynthesis pathways in response to EGCG and oxamate treatment were observed. The inhibition of LDHA by EGCG or oxamate impacts on various pathways of the cellular metabolic network and significantly modifies the cancer metabolic phenotype. These results suggest that phytochemical EGCG and LDHA inhibitor oxamate confer their anti-cancer activities by disrupting the balance of flux throughout the cellular metabolic network. [ABSTRACT FROM AUTHOR]

To estimate atmospheric predictability for multivariable system, based on information theory in nonlinear error growth dynamics, a quantitative method is introduced in this paper using multivariable joint predictability limit (MJPL) and corresponding single variable predictability limit (SVPL). The predictability limit, obtained from the evolutions of nonlinear error entropy and climatological state entropy, is not only used to measure the predictability of dynamical system with the constant climatological state entropy, but also appropriate to the case of climatological state entropy changed with time. With the help of daily NCEP-NCAR reanalysis data, by using a method of local dynamical analog, the nonlinear error entropy, climatological state entropy, and predictability limit are obtained, and the SVPLs and MJPL of the winter 500-hPa temperature field, zonal wind field and meridional wind field are also investigated. The results show that atmospheric predictability is well associated with the analytical variable. For single variable predictability, there exists a big difference for the three variables, with the higher predictability found for the temperature field and zonal wind field and the lower predictability for the meridional wind field. As seen from their spatial distributions, the SVPLs of the three variables appear to have a property of zonal distribution, especially for the meridional wind field, which has three zonal belts with low predictability and four zonal belts with high predictability. For multivariable joint predictability, the MJPL of multivariable system with the three variables is not a simple mean or linear combination of its SVPLs. It presents an obvious regional difference characteristic. Different regions have different results. In some regions, the MJPL is among its SVPLs. However, in other regions, the MJPL is less than its all SVPLs. [ABSTRACT FROM AUTHOR]

Carbon nanofibers with diameters that fall into submicron and nanometer range have attracted growing attention in recent years due to their superior chemical, electrical, and mechanical properties in combination with their unique 1D nanostructures. Unlike catalytic synthesis, electrospinning polyacrylonitrile (PAN) followed by stabilization and carbonization has become a straightforward and convenient route to make continuous carbon nanofibers. This paper is a comprehensive and state-of-the-art review of the latest advances made in development and application of electrospun PAN-based carbon nanofibers. Our goal is to demonstrate an objective and overall picture of current research work on both functional carbon nanofibers and high-strength carbon nanofibers from the viewpoint of a materials scientist. Strategies to make a variety of carbon nanofibrous materials for energy conversion and storage, catalysis, sensor, adsorption/separation, and biomedical applications as well as attempts to achieve high-strength carbon nanofibers are addressed. [ABSTRACT FROM AUTHOR]

In nonlinear error growth dynamics, the initial error cannot be accurately determined, and the forecast error, which is also uncertain, can be considered to be a random variable. Entropy in information theory is a natural measure of the uncertainty of a random variable associated with a probability distribution. This paper effectively combines statistical information theory and nonlinear error growth dynamics, and introduces some fundamental concepts of entropy in information theory for nonlinear error growth dynamics. Entropy based on nonlinear error can be divided into time entropy and space entropy, which are used to estimate the predictabilities of the whole dynamical system and each of its variables. This is not only applicable for investigating the dependence between any two variables of a multivariable system, but also for measuring the influence of each variable on the predictability of the whole system. Taking the Lorenz system as an example, the entropy of nonlinear error is applied to estimate predictability. The time and space entropies are used to investigate the spatial distribution of predictability of the whole Lorenz system. The results show that when moving around two chaotic attractors or near the edge of system space, a Lorenz system with lower sensitivity to the initial field behaves with higher predictability and a longer predictability limit. The example analysis of predictability of the Lorenz system demonstrates that the predictability estimated by the entropy of nonlinear error is feasible and effective, especially for estimation of predictability of the whole system. This provides a theoretical foundation for further work in estimating real atmospheric multivariable joint predictability. [ABSTRACT FROM AUTHOR]

Circulating endothelial progenitor cells (EPCs) are reduced in patients with systemic lupus erythematosus (SLE). A reduced number of EPCs are associated with the presence of atherosclerosis in other populations. We sought to determine whether the reduction in EPC numbers in SLE is dependent on the presence of advanced coronary artery calcification (CAC). Patients with SLE had previous coronary calcium scores which placed them in either the >75th percentile or <25th percentile for their age. Seventeen patients with SLE and 13 healthy controls (HC) were included in the study. White blood cells were stained for EPC and progenitor cell markers including CD34, CD133, and VEGFR and analyzed by flow cytometry. SLE patients had repeated coronary imaging as well as carotid ultrasound. There was no difference in age between groups. SLE patients with advanced CAC were more likely to be hypertensive, to be smokers, and to have longer disease duration than SLE patients without CAC. SLE patients without evidence of CAC had a significantly lower number of EPCs (CD34+/CD133+/VEGFR+) compared to HC (median (IQR)) 0 (0, 6.7) vs. 10.2 (5.8, 12.3) ( P = 0.02). Total numbers of PCs (CD133+/CD34+) were not significantly decreased in patients with SLE ((mean ± SEM) 1,007 ± 154 vs. 824 ± 170 ( P = 0.20)). No significant difference was seen in EPC number between SLE patients without CAC and those with advanced CAC. Increased carotid intima-media thickness did not correlate with CAC or EPC number in SLE patients. Reduced numbers of EPCs in SLE patients may be observed compared to HC even in the absence of CAC. Differences in measured risk factor profiles and depletion of total circulating PCs do not fully explain this finding. [ABSTRACT FROM AUTHOR]

Titania (TiO2) nanofibers were fabricated by electrospinning three representative spin dopes made of titanium (IV) n-butoxide (TNBT) and polyvinylpyrrolidone (PVP) with the TNBT/PVP mass ratio being 1/2 in three solvent systems including N,N-dimethylformamide (DMF), isopropanol, and DMF/isopropanol (1/1 mass ratio) mixture, followed by pyrolysis at 500 °C. The detailed morphological and structural properties of both the as-electrospun precursor nanofibers and the resulting final TiO2 nanofibers were characterized by SEM, TEM, and XRD. The results indicated that the precursor nanofibers and the final TiO2 nanofibers made from the spin dopes containing DMF alone or DMF/isopropanol mixture as the solvent had the common cylindrical morphology with diameters ranging from tens to hundreds of nanometers, while those made from the spin dope containing isopropanol alone as the solvent had an abnormal concave morphology with sizes/widths ranging from sub-microns to microns. Despite the morphological discrepancies, all precursor nanofibers were structurally amorphous without distinguishable phase separation, while all final TiO2 nanofibers consisted of anatase-phased TiO2 single-crystalline grains with sizes of approximately 10 nm. The electrospun TiO2 nanofiber mat is expected to significantly outperform other forms (such as powder and film) of TiO2 for the solar cell (particularly dye-sensitized solar cell) and photo-catalysis applications. [ABSTRACT FROM AUTHOR]

Aluminum is a known neurotoxin and a major environmental contributor to neurodegenerative diseases such as Alzheimer's disease (AD). We uesd a subchronic aluminum chloride exposure model in offspring rats by continuously treating them with AlCl3 solution from the date of birth until day 90 in this research. Then evaluated the neurobehavioral changes in rats, observed the ultrastructural changes of hippocampal synapses and neurons, and examined the level of hippocampal acetylated histone H3 (H3ac), the activity and protein expression of hippocampal HAT1 and G9a, and the protein expression level of H3K9 dimethylation (H3K9me2). The findings demonstrated that aluminum-treated offspring rats had impaired learning and memory abilities as well as ultrastructural alterations in hippocampal synapses and neurons. The level of histone H3ac was decreased along with decreased protein expression and activity of HAT1, while level of H3K9me2 was increased along with increased protein expression and activity of G9a. [ABSTRACT FROM AUTHOR]

A novel microvibration hammerhead consists of a piezoelectric actuator and a double cross-shape compliant mechanism (DCCM) is presented in this paper. The output force of the piezoelectric actuator can be detected in real time by an inside-installed pressure sensor. A theoretical model including the stiffness, first natural frequency, and stress of the DCCM and the displacement output of the piezoelectric actuator are established, and then they are further analyzed using the finite element analysis method. The effects of the beam thickness on the static and dynamic properties are deeply analyzed and compared. A prototype micro hammering system is constructed by integrating the microvibration hammerhead assembly and controlling system. Various experiments are also carried out to verify the basic performance of the micro hammering system.Highlights: A microvibration hammerhead including piezoelectric actuator, pressure sensor and DCCM was proposed. The static and dynamic models of the DCCM were theoretically established, which was validated to be available in the analysis of the stiffness, stress and resonant frequency. The relationships between the hammering force and initial contacting force, driving frequency and amplitudes were presented based on the experimental results. [ABSTRACT FROM AUTHOR]

In this paper, a statistical method called Generalized Equilibrium Feedback Analysis (GEFA) is used to investigate the responses of the North Pacific Storm Track (NPST) in the cold season to the multi-scale oceanic variations of the Kuroshio Extension (KE) system, including its large-scale variation, oceanic front meridional shift, and mesoscale eddy activity. Results show that in the cold season from the lower to the upper troposphere, the KE large-scale variation significantly weakens the storm track activity over the central North Pacific south of 30°N. The northward shift of the KE front significantly strengthens the storm track activity over the western and central North Pacific south of 40°N, resulting in a southward shift of the NPST. In contrast, the NPST response to KE mesoscale eddy activity is not so significant and relatively shallow, which only shows some significant positive signals near the dateline in the lower and middle troposphere. Furthermore, it is found that baroclinicity and baroclinic energy conversion play an important role in the formation of the NPST response to the KE multi-scale oceanic variations. [ABSTRACT FROM AUTHOR]

The Proper Orthogonal Decomposition (POD)-based ensemble four-dimensional variational (4DVar) assimilation method (POD4DEnVar) was proposed to combine the strengths of EnKF (i.e., the ensemble Kalman filter) and 4DVar assimilation methods. Recently, a POD4DEnVar-based radar data assimilation scheme (PRAS) was built and its effectiveness was demonstrated. POD4DEnVar is based on the assumption of a linear relationship between the model perturbations (MPs) and the observation perturbations (OPs); however, this assumption is likely to be destroyed by the highly non-linear forecast model or observation operator. To address this issue, using the Gauss-Newton iterative method, the nonlinear least squares enhanced POD4DEnVar algorithm (referred to as NLS-4DVar) was proposed. Naturally, the PRAS was upgraded to form the NLS-4DVar-based radar data assimilation scheme (NRAS). To evaluate the performance of NRAS against PRAS, observing system simulation experiments (OSSEs) were conducted to assimilate reflectivity and radial velocity individually, with one, two, and three iterations. The results demonstrated that the NRAS outperformed PRAS in improving the initial condition and the forecasting of model variables and rainfall. The NRAS, with a smaller number of iterations, can yield a convergent result. In contrast to the situation when assimilating radial velocity, the advantages of NRAS over PRAS were more obvious when assimilating reflectivity. [ABSTRACT FROM AUTHOR]

Aluminum (Al) is a neurotoxin that gradually accumulates in the brain in human life, resulting in oxidative brain injury related to Alzheimer's disease (AD) and other diseases. In this study, the learning and memory of rats exposed to different aluminum concentrations (0.0 g/L, 2.0 g/L, 4.0 g/L, and 8.0 g/L) were studied, and the learning and memory of rats were observed by shuttle box experiment. With hematoxylin and eosin staining, Western blot, immunofluorescence, and RT-PCR, the morphology of nerve cells in the hippocampus of rat brain were observed, and the levels of activator protein-1 (AP-1) gene and protein, nerve growth factor (NGF), neurotrophin-3 (NT3), glial cell line-derived neurotrophic factor (GDNF), and brain-derived neurotrophic factor (BDNF) gene and protein level, etc. The experimental results showed that subchronic aluminum exposure damaged learning and memory in rats. The cognitive function damage in rats was more evident after increasing the aluminum intake dose. The more aluminum intake, the more pronounced the histological changes in the hippocampus will be. The expression level and protein content of neurotrophic factors in the hippocampus of rats showed a negative correlation with aluminum intake. In this experiment, we explored the mechanism of aluminum exposure in learning and memory disorders, and provided some data reference for further elucidation of the damage mechanism of aluminum on the nervous system and subsequent preventive measures. [ABSTRACT FROM AUTHOR]

Maize ALKALINE ALPHA GALACTOSIDASE (ZmAGA) is a key enzyme in the raffinose metabolism pathway. We have previously characterized the ZmAGA1 gene as heat shock induced in germinating maize seeds. Here, we report that ZmAGA1 is induced in maize leaves by heat shock, dehydration, NaCl, abscisic acid (ABA), and salicylic acid. The 1622 bp of the 5′-regulatory region of the ZmAGA1 gene was isolated and characterized for promoter activity. The 5′-deletion assay of the regulatory region indicated that the region from −629 to −1 (relative to the start codon AUG) showed the greatest promoter activity, and the sequences upstream of this fragment act to inhibit transcription. The cis-acting element ABRE (ABA - responsive element) was identified to be functional. Increasingly, more refined 3′-deletion constructs of the regulatory region demonstrated that a 6-nucleotide (nt) RNA motif in the 5′-untranslated region (UTR) of the ZmAGA1 gene stimulates the translation of the downstream open reading frame (ORF). Deletion or triplication of this motif decreased or enhanced downstream ORF translation, respectively, while the mRNA abundance remained the same. RNA-EMSA (electrophoretic mobility shift assay) confirmed that some cytosolic protein(s) was (were) able to bind to this 6-nt RNA motif. This work contributes to our understanding of the ZmAGA1 gene regulatory mechanism and the metabolism of raffinose in maize cells. [ABSTRACT FROM AUTHOR]

In order to solve the problems of serious heating and easy ablation of conductive shaft in electrochemical machining of special-shaped deep hole with large aspect ratio, the two schemes of single-sided copper bar and symmetrical copper bar of conductive shaft are studied by ANSYS software. By establishing the thermoelectric coupling model of the conductive shaft, the distribution law of temperature field and thermal deformation of conductive shaft under different working conditions is analyzed. The conductive shaft structure based on symmetrical copper bar scheme is determined. Monitoring points are set at the key parts of the conductive shaft, and the temperature field distribution is verified by using the data acquisition card. The temperature acquisition results are consistent with the simulation results. Through the machining test of special-shaped inner spiral deep hole parts with large aspect ratio, the results show that under the conditions of working current of 15 000 A, feed rate of 5 mm/min, and continuous machining for 14 h, the forming accuracy of the workpiece is ± 0.15 mm and the surface roughness is better than Ra0.8 μm. The performance of the conductive shaft is stable and meets the actual processing requirements. The heat dissipation performance of the conductive shaft is optimized by providing air flow on the upper surface and side at the same time. [ABSTRACT FROM AUTHOR]

In order to solve the problem of uneven gap distribution and flow pattern in the complex parts with multi-stage internal cone hole in electrochemical machining, a method of computer simulation–assisted cathode design is proposed. The electric field and flow field models of machining gap are established respectively, and the simulations of different cathode profiles are carried out. When the cathode cone angle is 2°, the electric field distribution between the cathode and the workpiece is reasonable, and the electrolyte distribution in the machining gap is uniform. With the conditions of processing voltage 10 V, electrolyte inlet pressure 1.5 MPa, electrolyte temperature 28 ℃, and cathode feed speed 5 mm/min, the electrochemical machining (ECM) processing of multi-stage internal cone hole is carried out by using the optimized cathode. The results show that the surface of the workpiece has no flow pattern, the dimensional forming accuracy is better than 0.1 mm, and the surface roughness reaches Ra 0.697 μm. Research shows that the optimization of cathode structure with computer simulation can shorten the cathode development cycle and reduce the cost of cathode design effectively in ECM, which provides an efficient and feasible method for the optimization of complex cathode structure. [ABSTRACT FROM AUTHOR]

Properly accounting for the effect of heterogeneity of aquifers and accurately predicting mine water inflow during the mining process is still a challenging problem in China. We developed a stochastic modelling methodology that considers a large range of possible multi-scale fracture configurations and heterogeneous porous rock to predict mine water inflow close to the observed data. The coupled discrete fracture–rock matrix models were built for the Binhu coal mine 16,112 working face with the Monte Carlo method. The models were solved using the embedded discrete fracture model to calculate groundwater inflow from the aquifer beneath the coal seam floor. The calculated results and the observed groundwater inflows in the field agreed well. Sensitivity analysis indicates that groundwater inflow increases with increased fracture length and fracture density. The effect of natural fractures introduces a large uncertainty for the models, due to the existence of long fractures that could act as conduits between the Ordovician limestone and no. 14 aquifers. The results highlight the importance of multi-scale fractures on modeling and simulating flow in the mine area. [ABSTRACT FROM AUTHOR]

A series of novel imidazolium based ionic liquids containing the urea moiety were designed and synthesized for anion recognition. 1-Ethylurea-3-methylimidazolium acetate ([Eumim]OAc) was used as the receptor for the halides and complex anions (BF, PF, BPh). H NMR spectra showed that the urea protons and imidazolium C(2) proton of the receptor ([Eumim]OAc) moved upfield on addition of various anions. A Job plot showed that the [Eumim]OAc receptor formed a 1:1 complex with BPh. X-ray diffraction analysis and the molecular modeling study revealed that the conformations of [Eumim]OAc and [Eumim]BPh were different. The conformational change of the cation was caused by anion exchange, and may provide an alternative to current methods for recognition of anions. [ABSTRACT FROM AUTHOR]

Purpose: To define and analyze the learning curve of percutaneous endoscopic transforaminal decompression (PETD) for lumbar spinal stenosis (LSS).Methods: From July 2015 to September 2016, 78 patients underwent PETD; one of whom was converted to open surgery, two were lost, and 75 were included in this study. Clinical results were assessed by using the Oswestry Disability Index (ODI) and visual analog scale (VAS). The learning curve was assessed by a logarithmic curve-fitting regression analysis. Of these 75 patients, 35 were defined as the "early" group, and 40 were defined as the "late" group for comparison.Results: The mean follow-up was 25.37 ± 4.71 months. The median operative time gradually decreased from 95 (interquartile range, IQR, 85-110) minutes for the early group to 70 (IQR, 60-80) minutes for the late group (P < .000), and an asymptote was reached after approximately 35 cases. After surgery, the VAS for leg pain (LP) and ODI decreased significantly and remained constant during the follow-up. However, the VAS of low back pain (LBP) increased mildly. The total complication rate was 6.6%. ODI, VAS of LP and of LBP, and complication rate did not significantly differ between two groups. Early ambulation and short hospital stay after surgery were achieved.Conclusion: The learning curve of PETD for LSS was assessed and good clinical results were achieved. The surgeon's experience with this technique correlated with reduced operation time. Proper patient selection, familiarity with pathological anatomy, and manipulation under endoscopic view may shorten the learning curve and decrease complications. [ABSTRACT FROM AUTHOR]

Raindrop size distribution (RSD) characteristics over the South China Sea (SCS) are examined with onboard Parsivel disdrometer measurements collected during marine surveys from 2012 to 2016. The observed rainfall is divided into pre-monsoon, monsoon, and post-monsoon periods based on the different large-scale circumstances. In addition to disdrometer data, sounding observation, FY-2E satellite, SPRINTARS (Spectral Radiation-Transport Model for Aerosol Species), and NCEP reanalysis datasets are used to illustrate the dynamical and microphysical characteristics associated with the rainfall in different periods. Significant variations have been observed in respect of raindrops among the three periods. Intercomparison reveals that small drops (D < 1 mm) are prevalent during pre-monsoon precipitation, whereas medium drops (1–3 mm) are predominant in monsoon precipitation. Overall, the post-monsoon precipitation is characterized by the least concentration of raindrops among the three periods. But, several large raindrops could also occur due to severe convective precipitation events in this period. Classification of the precipitation into stratiform and convective regimes shows that the lg(Nw) value of convective rainfall is the largest (smallest) in the pre-monsoon (post-monsoon) period, whereas the Dm value is the smallest (largest) in the pre-monsoon (post-monsoon) period. An inversion relationship between the coefficient A and the exponential b of the Z—R relationships for precipitation during the three periods is found. Empirical relations between Dm and the radar reflectivity factors at Ku and Ka bands are also derived to improve the rainfall retrieval algorithms over the SCS. Furthermore, the possible causative mechanisms for the significant RSD variability in different periods are also discussed with respect to warm and cold rain processes, raindrop evaporation, convective activities, and other meteorological factors. [ABSTRACT FROM AUTHOR]

Purpose: This study reports a new technique known as percutaneous endoscopic trans-articular discectomy (PETAD) for huge central/paracentral lumbar disc herniation (LDH).Methods: Sixteen patients with huge central/paracentral LDH who underwent PETAD in our department from July 2015 to July 2016 were retrospectively analyzed. Clinical outcomes were evaluated according to pre-operative and post-operative visual analog scale (VAS) and Oswestry disability index (ODI) scores and the MacNab criteria. Immediate post-operative MRI and CT were conducted to confirm complete removal of LDH along with follow-up flexion-extension X-ray to observe lumbar stability.Results: The huge central/paracentral LDH was completely removed by PETAD in 16 patients, as confirmed by post-operative MRI and CT. Leg pain was eased after removal of the disc herniations. The satisfactory (excellent/good) results were 93.7%. The mean follow-up duration was 15.6 (range, 3-24) months. The mean pre-operative VAS and ODI scores were 5.72 ± 1.18 (range, 4-9) and 60.1 (range, 51-87), respectively, which decreased to 1.26 ± 0.81 (range, 0-3) and 18.1 (range, 10-31), respectively at the third month post-operatively and to 0.78 ± 0.62 (range, 0-1) and 7.2 (range, 0-15), respectively by the last follow-up visit. No recurrence and segmental instability was observed in any of the 16 patients during the follow-up period.Conclusion: PETAD could be a good alternative for treatment of huge central/paracentral LDH. [ABSTRACT FROM AUTHOR]

As a relatively new grinding technology, ELID (electrolytic in-process dressing) is widely used in some businesses. The oxide layer plays an important role in ELID grinding performance. The purpose of this work is to investigate the state of the oxide layer on ELID grinding wheel surfaces based on workpiece-cathode and tool-cathode. The thickness and surface topography of the oxide layer were measured from ELID grinding experiments based on workpiece-cathode and tool-cathode in different controlled dressing current. The normal grinding force was also compared in ELID grinding with workpiece-cathode and tool-cathode. According to the results, there are some caves on the surface of the oxide layer in ELID grinding with workpiece-cathode. With increasing controlled dressing current, the surface of the oxide layer becomes discontinuous in ELID grinding with workpiece-cathode. And the surface of the oxide layer becomes smoother with increasing controlled dressing current in ELID grinding with tool-cathode. Meanwhile, it was found that the oxide layer in ELID grinding with workpiece-cathode is thicker than that in ELID grinding with tool-cathode. Moreover, the normal grinding force in ELID grinding with workpiece-cathode is smaller than that in ELID grinding with tool-cathode. The results are helpful to improve the ELID grinding performance and apply ELID grinding technology with workpiece-cathode to abroad industrial applications. [ABSTRACT FROM AUTHOR]

During the past two decades, the exhibition industry in China has been developing rapidly and has become an important part of the modern service industry, particularly the agglomeration characteristics of exhibition enterprises highlighted on the regional scale. Although the development of theoretical research on the western exhibition industry has taken place over time, the spatial perspective has not been at the centre of attention so far. This paper aims to fill this gap and report on the agglomeration characteristics of exhibition enterprises and their influential factors. Based on data about exhibition enterprises in the Pearl River Delta (PRD) during 1991-2013, using the Ripley K function analysis and kernel density estimation, this research identifies that: 1) the exhibition enterprise on the regional scale is significantly characterized by spatial agglomeration, and the agglomeration density and scale are continuously increasing; 2) the spatial pattern of agglomeration has developed from a single-center to multi-center form. Meanwhile, this paper profiles the factors influencing the spatial agglomeration of exhibition enterprises by selecting the panel data of nine cities in the PRD in 1999, 2002, 2006 and 2013. The results show that market capacity, urban informatization level and exhibition venues significantly influence the location choice of exhibition enterprises. Among them, the market capacity is a variable that exerts a far greater impact than other factors do. [ABSTRACT FROM AUTHOR]

Soybean cyst nematode (SCN) ( Heterodera glycines Ichinohe) is a highly recalcitrant endoparasite of soybean roots, causing more yield loss than any other pest. To identify quantitative trait loci (QTL) controlling resistance to SCN (HG type 2.5.7, race 1), a genome-wide association study (GWAS) was performed. The association panel, consisting of 120 Chinese soybean cultivars, was genotyped with 7189 single nucleotide polymorphism (SNPs). A total of 6204 SNPs with minor allele frequency >0.05 were used to estimate linkage disequilibrium (LD) and population structure. The mean level of LD measured by r declined very rapidly to half its maximum value (0.51) at 220 kb. The overall population structure was approximately coincident with geographic origin. The GWAS results identified 13 SNPs in 7 different genomic regions significantly associated with SCN resistance. Of these, three SNPs were localized in previously mapped QTL intervals, including rhg1 and Rhg4. The GWAS results also detected 10 SNPs in 5 different genomic regions associated with SCN resistance. The identified loci explained an average of 95.5% of the phenotypic variance. The proportion of phenotypic variance was due to additive genetic variance of the validated SNPs. The present study identified multiple new loci and refined chromosomal regions of known loci associated with SCN resistance. The loci and trait-associated SNPs identified in this study can be used for developing soybean cultivars with durable resistance against SCN. [ABSTRACT FROM AUTHOR]

Spring soybean cultivars produced in moderate climates currently represent almost the entire soybean industry; however, soybean production has the potential to be extended into the summer months in different regions of the world. It is critical to select the correct soybean cultivar for production in a specific environment. The purpose of this study was therefore to evaluate the productivity (yield) and stability of the current summer soybean cultivars in multi-environment trials in the Huang-Huai-Hai region, presently the largest summer soybean-producing region in the world, to determine which cultivars will be most successful for large scale production in this region, as well as those that should be used in future breeding efforts. A total of 94 summer soybean cultivars were grown in the three major soybean production provinces, i.e., Shandong, Henan, and Hebei, over 3 years (2008-2010). The GGEbiplot™ software provided a 'genotype x genotype-by-environment interaction' function to evaluate the importance of agronomic factors controlling the soybean yield of each cultivar across the nine different environments. Xudou10, Zhonghuang39, Lu93748-1 and Lu99-1 exhibited relatively high average yields. The stability among the high-yielding cultivars was ranked in decreasing order as Xudou10, Zheng99048, Jidou7, Yudou18, and Gaozuoxuan-1. Among all recorded factors, the pod number per plant was the most important factor controlling yield, followed by seed number per plant, effective branch number, and 100-seed weight, which positively affected soybean yield. In contrast, a higher bottom pod height, greater number of nodes on the main stem, and longer growth duration were negatively correlated with yield. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau, with an average altitude above 4000 m, is the highest and largest plateau in the world. The frequency of thunderstorms in this region is extremely high. Many indices are used in operational forecasting to assess the stability of the atmosphere and predict the probability of severe thunderstorm development. One of the disadvantages of many of these indices is that they are mainly based on observations from plains. However, considering the Plateau's high elevation, most convective parameters cannot be applied directly, or their application is ineffective. The pre-convective environment on thunderstorm days in this region is investigated based on sounding data obtained throughout a five-year period (2006-10). Thunderstorms occur over the Tibetan Plateau under conditions that differ strikingly from those in plains. On this basis, stability indices, such as the Showalter index (including SI and SI), and the K index are improved to better assess the thunderstorm environments on the Plateau. Verification parameters, such as the true-skill statistic (TSS) and Heidke skill score (HSS), are adopted to evaluate the optimal thresholds and relative forecast skill for each modified index. Lastly, the modified indices are verified with a two-year independent dataset (2011-12), showing satisfactory results for the modified indices. For determining whether or not a thunderstorm day is likely to occur, we recommend the modified SI index. [ABSTRACT FROM AUTHOR]

Rationale: The preference for and reaction to novelty are strongly associated with addiction to cocaine and other drugs. However, the genetic variants and molecular mechanisms underlying these phenomena remain largely unknown. Although the relationship between novelty- and addiction-related traits has been observed in rats, studies in mice have failed to demonstrate this association. New, genetically diverse, high-precision mouse populations including Diversity Outbred (DO) mice provide an opportunity to assess an expanded range of behavioral variation enabling detection of associations of novelty- and addiction-related traits in mice. Methods: To examine the relationship between novelty- and addiction-related traits, male (n = 51) and female (n = 47) DO mice were tested on open field exploration, hole board exploration, and novelty preference followed by intravenous cocaine self-administration (IVSA; ten 2-h sessions of fixed ratio 1 and one 6-h session of progressive ratio). Results: We observed high variation of cocaine IVSA in DO mice with 43 % reaching and 57 % not reaching conventional acquisition criteria. As a group, mice that did not reach these criteria still demonstrated significant lever discrimination. Mice experiencing catheter occlusion or other technical issues ( n = 17) were excluded from the analysis. Novelty-related behaviors were positively associated with cocaine IVSA. Multivariate analysis of associations among novelty- and addiction-related traits revealed a large degree of shared variance (45 %). Conclusions: Covariation among cocaine IVSA and novelty-related phenotypes in DO mice indicates that this relationship is amenable to genetic dissection. The high genetic precision and phenotypic diversity in the DO may facilitate discovery of previously undetectable mechanisms underlying predisposition to develop addiction disorders. [ABSTRACT FROM AUTHOR]

Exposure to rare earth elements (REEs) is known to impair intelligence in children and cause neurobehavioral abnormalities in animals. However, the mechanisms underlying these phenomena are not clear. Lanthanum is often used to study the effects of REEs. The aim of this study was to investigate the influence of lanthanum chloride (LaCl 3) on spatial learning and memory and a possible underlying mechanism involving nuclear factor-kappa B (NF-κB) signalling pathway expression in the hippocampus. The rats were exposed to 0, 0.25, 0.50 or 1.00 % LaCl 3 in drinking water during pregnancy and lactation (i.e. while feeding their offspring). After weaning, young rats continued to receive 0, 0.25, 0.50 and 1.00 % LaCl 3 in the drinking water for 1 month. LaCl 3 exposure impaired the spatial learning and memory of young rats and significantly decreased the expression of phosphorylated IκB kinase complex, phosphorylated IκBα, NF-κB, c-fos, c-jun and brain-derived neurotrophic factor in the hippocampus. These results indicate that LaCl 3 exposure impairs spatial learning and memory in rats by inhibiting NF-κB signalling pathway. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to investigate the relationship between age and synchronous liver metastasis in female colorectal cancer patients. Method: Clinical and pathological data from 655 consecutive female patients who were treated in Qilu Hospital from January 2000 to January 2010 were reviewed. First, the patients were divided into two groups: 60 years or younger and 61 years or older. A chi-square test was adopted to analyse the difference in clinicopathological characteristics between the two groups. Then, they were classified into two groups according to liver metastasis. Univariate analysis and logistic multivariate regression analysis were adopted to discriminate risk factors of liver metastasis. Results: The chi-square test demonstrated that significant difference existed between the younger and the older groups in terms of liver metastasis ( P < 0.001), lymph node metastasis ( P < 0.001), tumour localization ( P < 0.001), tumour invasion depth ( P < 0.001), type of tumour ( P < 0.001), tumour cell differentiation ( P < 0.001) and venous invasion ( P < 0.001). Univariate analysis demonstrated that seven factors are associated with liver metastasis. Logistic regression analysis indicated that age ( P = 0.005), tumour size ( P < 0.001), tumour invasion depth ( P = 0.001), tumour cell differentiation ( P = 0.029) and type of tumour ( P < 0.001) are independent risk factors of liver metastasis. Conclusions: The liver metastatic potential of colorectal cancer may be different between younger and older female patients. Age may independently influence liver metastasis in female colorectal cancer patients. [ABSTRACT FROM AUTHOR]

Products of Al-deoxidation reaction in iron melt are the most common inclusions and play an important effect on steel performance. Understanding the thermodynamics on nano-alumina (or nano-hercynite) is very critical to explore the relationship between Al-deoxidation reaction and products growth in iron melt. In present study, a thermodynamic modeling of nano-alumina inclusions in Fe–O–Al melt has been developed. The thermodynamic results show that the Gibbs free energy changes for the formation of nano-Al2O3 and nano-FeAl2O4 decrease with the increasing size and increase with the increasing temperature. The Gibbs free energy changes for transformation of nano-Al2O3 into bulk-Al2O3 increase with the increasing size and temperature. The thermodynamic curve of nano-alumina (or nano-hercynite) and the equilibrium curve of bulk-alumina (or bulk-hercynite) obtained in this work are agree with the published experimental data of Al-deoxidation equilibria in liquid iron. In addition, the thermodynamic coexisting points about Al2O3 and FeAl2O4 in liquid iron are in a straight line and coincide with the various previous data. It suggested that these scattered experimental data maybe in the different thermodynamic state of Al-deoxidized liquid iron and the reaction products for most of the previous Al-deoxidation experiments are nano-alumina (or nano-hercynite). [ABSTRACT FROM AUTHOR]

Considering the large amount and high frequency application of concentrated fertilizer nitrogen in the Black Soil Region of Northeast China, the current laboratory/field simulation study aimed to explore the pollution risk of added nitrogen in black soil to groundwater and identify effective measures to prevent and control soil nitrogen leaching with an undisturbed soil column. The results showed that the saturated nitrogen adsorption capacities increased by 1.7%, 7.7% and 18.5% in ploughing, impervious agent (starch grafted polyacrylic acid) addition, and corn straw returning treatments, respectively, relative to the control (no-till). When the collection volume of the leaching solution reached the experimental maximum (4,000 mL), the total amount of nitrogen leaching from the control soil column (i.e., the no-tillage treatment) accounted for more than 50% of the added nitrogen, indicating a great risk of nitrogen pollution in groundwater. Compared with the no-tillage treatment, the amount of nitrogen leaching from the ploughing treatment increased insignificantly, and the amount of nitrogen leaching in the following spring in the corn straw returning treatment increased by 11.2%. The amount of nitrogen leaching decreased by 12.5% in the soil sampled in autumn of the second year. The total amount of nitrogen leaching in the soil with impervious agents decreased by 40.1%. Therefore, the permeability-reducing agent could significantly reduce underground water pollution risk posed by nitrogen leaching. [ABSTRACT FROM AUTHOR]

Flooding can lead to yield reduction of soybean. Therefore, identification of flooding tolerance genes has great significance in production practice. In this study, Qihuang 34, a highly-resistant variety to flooding stress, was selected for submergence treatments. Transcriptome and proteome analyses were conducted, by which twenty-two up-regulated differentially expressed genes (DEGs)/differentially expressed proteins (DEPs) associated with five KEGG pathways were isolated. The number of the DEGs/DEPs enriched in glycolysis/gluconeogenesis was the highest. Four of these genes were confirmed by RT-qPCR, suggesting that glycolysis/gluconeogenesis may be activated to generate energy for plant survival under anaerobic conditions. Thirty-eight down-regulated DEGs/DEPs associated with six KEGG pathways were identified under submergence stress. Eight DEGs/DEPs enriched in phenylpropanoid biosynthesis were assigned to peroxidase, which catalyzes the conversion of coumaryl alcohol to hydroxy-phenyl lignin in the final step of lignin biosynthesis. Three of these genes were confirmed by RT-qPCR. The decreased expression of these genes led to the inhibition of lignin biosynthesis, which may be the cause of plant softening under submergence stress for a long period of time. This study revealed a number of up-/down-regulated pathways and the corresponding DEGs/DEPs, by which, a better understanding of the mechanisms of submergence tolerance in soybean may be achieved. [ABSTRACT FROM AUTHOR]

Leaf rust caused by Puccinia triticina is one of the main diseases affecting wheat (Triticum aestivum) production worldwide. Calmodulin (CaM) was found involved in the early stage of signal transduction pathway in response to P. triticina in wheat. To study the function and molecular mechanism of calmodulin (CaM) in signal transduction of wheat against P. triticina, we cloned a putative calmodulin-binding transcription activator (TaCAMTA4), and characterized its molecular structure and functions by using the CaM-encoding gene (TaCaM4-1) as a bait to screen the cDNA library from P. triticina infected wheat leaves. The open reading frame of TaCAMTA4 was 2505 bp encoding a protein of 834 aa, which contained all the four conserved domains of family (CG-1 domain, TIG domain, ANK repeats and CaM-binding domain). TaCaM4-1 bound to TaCAMTA4 by the C-terminal CaM-binding domain in Ca2+-dependent manner in the electrophoretic mobility shift assay (EMSA). Bimolecular fluorescence complementation (BiFC) analysis indicated that the interaction of TaCAMTA4 and TaCaM4-1 took place in the cytoplasm and nucleus of epidermal leaf cells in N. benthamiana. The expression level of TaCAMTA4 genes was down-regulated in incompatible combination after P. triticina infection. Furthermore, virus-induced gene silencing (VIGS)-based knockdown of TaCAMTA4 and disease assays verified that silencing of TaCAMTA4 resulted in enhanced resistance to P. triticina race 165. These results suggested that TaCAMTA4 function as negative regulator of defense response against P. triticina. [ABSTRACT FROM AUTHOR]

Through electrostatic interaction and high-temperature reduction methods, rGO was closely coated onto the surface of TiO2 nanotubes. Even at a high temperature of 700 °C, the nanotube morphology of TiO2 (anatase) was preserved because of the assistance of rGO, which provides a framework that prevents the tubes from breaking into particles and undergoing a phase transformation. The rGO/TiO2 nanotubes deliver a high capacity (263 mAh g−1 at the end of 100 cycles at 0.1 A g−1), excellent rate performance (151 mAh g−1 at 2 A g−1 and 102 mAh g−1 at 5 A g−1), and good cycle stability (206 mAh g−1 after 500 cycles at 0.5 A g−1). These characteristics arise from the GO/TiO2 nanotubes' advanced structure. First, the closely coated rGO and Ti3+ in the tubes give rise to a high electro-conductivity of the nanotubes. Additionally, the Li+ ions can rapidly transfer into the electrode via the nanotubes' empty inner diameter and short tube wall. [ABSTRACT FROM AUTHOR]