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In order to study the geological characteristics and tectonic implications of the Nanxiong Fault Belt in the northern margin of Nanxiong Basin, nionzonitic granite and diabase in the middle of Nanxiong Fault Bet are taken as the research object. Based on the study of field geological exploration, petro-geochemistry and LA-ICP-MS zircon U-Pb chronology, the petrological characteristics, major element characteristics, trace element characteristics and chronological characteristics of monzonitic granite and diabase have been analyzed in detail. In addition, the petrogeneses and tectonic implications of mon- zoonotic granite and diabase have been strictly discussed. This result shows that the monzonitic granite in the middle of Nanxiong Fault Bet is peraluminous high-K calc-alkalic rock series with geochemical characteristics of S-type granite. The light rare earth elements(LREE) are remarkably enriched. The monzonotic granite samples are intensely enriched in Rb, Th, K, Sr, Pb and obviously depleted in Nb, Ta, Ti with an obvious negative anomaly. The LA-ICP-MS zircon U-Pub doing results of the monzonitic grant samples yield a 206 pb/238 U weighted mean age of (448.5 ± 6.8) Ma. This monzonotic granite belongs to syn-collision granitoids, the REE geochemical characteristics of which are similar to those of oceanic volcanic arc granite(VAG). This study indicates that the diabase in the middle of Nanxiong Fault Belt is a quasi-aluminous calc-alkainne rock series. The diabase samples are obviously enriched in Sr, Pb, Ta, Ti, Nb, Rb and evidently deleted in Pr, Sm, Gd, Tb, Ho. The 206 pb/238 U weighted mean age of (437.2 ± 3.5) Ma. The diabase samples have the trace element geochemical characteristics of enriched mid-oceanic ridge basalt(E-MORB), which are formed in the tectonic environment of mid-oceanic ridge near the trench. The magma is derived from the enriched mantic. It is evidently believed that there was a regional tectonic stress transformation from compression to extension during 448 to 437 Ma. And magma fractional crystallization is accompanied by the crus--derived material remitting and the participation of Hands in the process of the intense magnetic activity, undergoing the late mantic-derived magma intrusion. The research results provide the structural geological and chronological evidence for provenance analysis and the study of the relationship between granite bodies, offer the basic scientific references for further identification of characteristics of uranium mineralization and metallogeny, and have the application value for the research on tectonic implications and fault-controlling characteristics of Nanxiong Fault Belt. [ABSTRACT FROM AUTHOR]

C14H12ClNO3, monoclinic, P21/n (no. 14), a = 7.2044(6) Å, b = 24.975(2) Å, c = 7.8562(8) Å, β = 115.231(1)°, V = 1278.7(2) Å3, Z = 4, Rgt(F) = 0.0538, wRref(F2) = 0.1430, T = 298 K.

In the past dozen years, the cases of tramadol intoxication have become frequent in many countries. Most previous studies focused on tramadol's pharmacology, such as pharmacokinetics, pharmacodynamics and pharmacogenetics. However, the dynamic distribution and postmortem redistribution (PMR) of tramadol remain unclear. Our study aimed to investigate these two issues systematically in various specimens of 216 poisoned male rats. A validated gas chromatography–mass spectrometry method was used in this study to measure the concentrations of tramadol. In the first part, 66 tramadol poisoned rats were sacrificed at 11 different time points and their organs were collected separately for the study of tramadol's dynamic distribution, which made it feasible to investigate its PMR later on. The results of this part showed that tramadol's concentrations varied according to the organ and time, and peaked 2 h after intragastric administration in the specimens of liver, kidney, spleen, lung, brain and heart-blood (except stomach and heart). Based on the results of the first part, the concentration of tramadol peaked 2 h in most tissues. Therefore, this time point was used for the study of tramadol's PMR. In the second part, the remaining 150 rats were sacrificed 2 h after intragastric administration of tramadol, and the carcasses were stored under three different conditions (−20, 4 and 20°C). The autopsy was carried out at eight different time points and their organs were collected separately. The results of this part showed that under storage temperatures of −20 and 4°C, the concentrations of tramadol in individual organs showed no significant changes at different time points whereas under a storage temperature of 20°C, the concentrations in certain organs (liver, kidney, spleen, lung, brain and heart-blood) increased significantly at the last few time points. PMR of tramadol was therefore confirmed. The process of PMR of tramadol could be slowed or stopped at lower storage temperatures (−20 or 4°C), which is significant in cases of suspected tramadol poisoning. [ABSTRACT FROM AUTHOR]

Male Sprague-Dawley rats (n = 18) were randomly divided into three groups: a saline group (20 mL/kg by gavage), a ketamine (KET) group (100 mg/kg by gavage), and a KET (the same routes and doses) combined with levo-tetrahydropalmatine (l-THP; 40 mg/kg by gavage) group (n = 6). Blood samples were acquired at different time points after drug administration. A simple and sensitive ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was established to determine the concentrations of KET and its metabolite, norketamine (NK), in rat plasma. Chromatographic separation was achieved using a BEH C18 column (2.1 mm × 50 mm , 1.7 μm) with chlorpheniramine maleate (Chlor-Trimeton) as an internal standard (IS). The initial mobile phase consisted of acetonitrile–water with 0.1% methanoic acid (80 : 20, v / v). The multiple reaction monitoring (MRM) modes of m/z 238.1→m/z 179.1 for KET, m/z 224.1→m/z 207.1 for NK, and m/z 275→m/z 230 for Chlor-Trimeton (IS) were utilized to conduct a quantitative analysis. Calibration curves of KET and NK in rat plasma demonstrated good linearity in the range of 2.5–500 ng/mL (r > 0.9994), and the lower limit of quantification (LLOQ) was 2.5 ng/mL for both. Moreover, the intra- and interday precision relative standard deviation (RSD) of KET and NK were less than 4.31% and 6.53%, respectively. The accuracies (relative error) of KET and NK were below -1.41% and -6.07%, respectively. The extraction recoveries of KET and NK were more than 81.23 ± 3.45 % and 80.42 ± 4.57 %, respectively. This sensitive, rapid, and selective UPLC-MS/MS method was successfully applied to study the pharmacokinetic effects of l-THP on KET after gastric gavage. The results demonstrated that l-THP could increase the bioavailability of KET and promote the metabolism of KET. The results showed that l-THP has pharmacokinetics effects on KET in rat plasma. [ABSTRACT FROM AUTHOR]

A finite element model of electromagnetic blanking forming processes with field shape was established based on LS-DYNA R8.0 software for diaphragms used in carrier rocket n aerospace field, and the variation rules of current, magnetic field, and sheet stress states under the field shape case were revealed. Furthermore, the processing parameters of the discharge voltage and the billet diameter were optimized. The results show that the section quality is optimized and the shear deformation is intensified with using the field shape. The sheets present a tearing fracture mode under the forming processes. With the increase of the discharge voltages, the deformation degree of the sheets increases, the fillet area of the fracture decreases and the diameter of the blanking part decreases firstly increases. With the increase of the billet diameters, the deformation degree of the sheets increases firstly and then decreases, the fillet area of the fracture decreases firstly and then increases, and the diameter of the blanking part increases and then and then decreases. The optimum values of the discharges voltages and the billet diameters are as 12 kV and 130 mm respectively. [ABSTRACT FROM AUTHOR]

Electromagnetic flanging is a potential forming technology for aluminum alloy. However, due to the temporal and spacial varied magnetic force acting on the workpiece, the forming process is not easy to be studied by experimental method and the final shape of the workpiece is difficult to control. This paper aims to investigate the forming process by numerical simulation and to utilize an efficient method to control the formed shape. The result shows that the plastic strain before collision is determined by the geometry, but not dependent on the discharge energy. The collision between the workpiece and die is benefit to the forming. The strain to failure of the annealed 2219 aluminum alloy for electromagnetic forming is 77.8% higher than that for quasi-static. In addition, the final shape of the workpiece can be precisely controlled by designing an appropriate die compensation angle. [ABSTRACT FROM AUTHOR]

Electromagnetic forming (EMF) is a high-speed forming technology, which can not only improve the formability of hard-to-form materials but also reduce springback. Electromagnetic high-speed impact can further improve the formability compared with electromagnetic free forming. The microscopic deformation mechanism of electromagnetic high-speed impact of aluminum alloy is discussed in this paper. The microstructures of electromagnetic high-speed impact of an aluminum alloy sheet were characterized. The microscopic deformation mechanisms of electromagnetic forming and electromagnetic high-speed impact were shown, respectively. The research results showed that electromagnetic high-speed impact could significantly improve the microhardness of the workpiece. The grains broke up and then became small subgrains during electromagnetic high-speed impact. The deformation mechanism was dominated by dislocation cross slip under electromagnetic high-speed impact. [ABSTRACT FROM AUTHOR]

• Methamphetamine (METH) induced conditioned place preference (CPP) in mice. • L-THP attenuated METH-induced CPP in mice. • METH induced upregulation of ERK phosphorylation in nucleus accumbens (NAc) and prefrontal cortex (PFc) of mice. • L-THP decreased the high expression of ERK phosphorylation induced by METH in NAc and PFc of mice. Levo-tetrahydropalmatine (L-THP) is the main active ingredient of traditional Chinese herbal medicine Corydalis and Stephania , which have been used for sedative, neuroleptic, and analgesic purposes. Previous studies have demonstrated that L-THP has antagonistic activation on dopamine receptors. Despite its effectiveness on treating drug addiction, L-THP's underlying molecular mechanisms in modulating methamphetamine (METH) reward behavior remain unclear. In order to clarify the mechanisms behind, we designed an experiment of conditioned place preference (CPP) to investigate the effects of L-THP on METH-induced CPP in mice. We then dissected the underlying molecular mechanisms of L-THP in modulating METH-induced CPP by evaluating accompanying changes in expression of phosphorylated extracellular signal-regulated kinase (p-ERK) in reward-relevant brain regions, including nucleus accumbens (NAc), prefrontal cortex (PFc), caudate putamen (CPu), and hippocampus (Hip), which may mediate the effects of L-THP on METH-induced CPP. The results showed that 1.0 mg/kg METH could induce obvious CPP in mice; 10.0 mg/kg L-THP could significantly attenuate METH-induced CPP in mice, though it could not induce CPP or conditioned place aversion by itself. Moreover, the levels of p-ERK in NAc and PFc of the METH group were significantly higher than that of the saline group. Although there was no evident difference between the levels of p-ERK of the L-THP group with that of the saline group, the levels of p-ERK in NAc and PFc of the M + T group were significantly lower than that of the METH group. There was no striking difference among the levels of p-ERK in CPu and Hip of all experimental groups. Our research suggested that NAc and PFc function as circuits contributing to METH addiction, and the activation of the ERK phosphorylation plays an important role in the mechanisms of METH addiction. Besides, L-THP significantly decreased ERK phosphorylation's high expression induced by METH, which suggested that the inhibitory effect of L-THP on modulating METH reward behavior may be related to the suppression of ERK phosphorylation in NAc and PFc of mice. In conclusion, L-THP could suppress the reward properties of METH, therefore, it may be a promising candidate for the treatment of METH addiction. [ABSTRACT FROM AUTHOR]

An increasing demand exists within the automotive industry to utilize aluminum alloy sheets because of their excellent strength-weight ratio and low emissions, which can improve fuel economy and reduce environmental pollution. High-speed automobile impactions are complicated and highly nonlinear deformation processes. Thus, in this paper, a Gurson-Tvergaard-Needleman (GTN) damage model is used to describe the damage behavior of high-speed electromagnetic impaction to predict the fracture behavior of 5052-O aluminum alloy under high-speed impaction. The parameters of the GTN damage model are obtained based on high-speed electromagnetic forming experiments via scanning electron microscopy. The high-speed electromagnetic impaction behavior process is analyzed according to the obtained GTN model parameters. The shape of the high-speed electromagnetic impaction in the numerical simulations agrees with the experimental results. The analysis of the plastic strain and void volume fraction distributions are analyzed during the process of high-speed impact, which indicates the validity of using the GTN damage model to describe or predict the fracture behavior of high-speed electromagnetic impaction. [ABSTRACT FROM AUTHOR]

In the process of electromagnetic forming (EMF), the rebound effect caused by high speed collision between sheet and die will affect the fittability, which results in a bad forming quality of workpiece. In this paper, finite element models of direct EMF and indirect EMF with an elastic medium are established, the influence factors of fittability in indirect EMF are studied, the two forming processes are compared, and the mechanisms of reduced rebound effect in indirect EMF are revealed. The results show that: in indirect EMF, with the increase of the discharging voltage or thickness of rubber, the fittability increases and then decreases; when the thickness of driver plate is equal to the skin depth of the driver plate, the fittability is the best. The optimal process parameters of indirect EMF are as follows: the discharging voltage is 10 kV, the thickness of the rubber is 20 mm and the thickness of driver plate is 2 mm. The rebound effect in indirect EMF is reduced compared with direct EMF for the following reasons: the impact force caused by the collision between the sheet and die is balanced by the pressure provided by the rubber; the sheet is always under tensile stress state due to the friction force provided by rubber; the remaining kinetic energy of sheet after collision with the die is absorbed by rubber. Therefore, the rebound effect in indirect EMF is suppressed compared with direct EMF. So, the fittability of the workpiece is improved, which results in a better forming quality. [ABSTRACT FROM AUTHOR]

The formability of aluminum alloy sheet in electromagnetic impaction deformation has attracted the attention of numerous researchers for the past decades. However, the influences of die geometry and high-speed impaction electromagnetic deformation on formability have not been well established, thereby resulting in the formability of the sheet not being developed fully. In this study, the influence of die geometry on the formability of 5052 aluminum alloy in electromagnetic deformation was investigated by comparing the formability of 5052 aluminum alloys formed using a hemispherical die and a cylindrical die. The intriguing finding is that the formability of the 5052 aluminum alloy formed using a cylindrical die is considerably higher than that formed using a hemispherical die. Therefore, die geometry significantly influences the formability of 5052 aluminum alloy. The influence of die geometry on the formability of 5052 aluminum alloy in high-speed impaction electromagnetic deformation was explained in terms of strain rate, pressure stress, and stress state. This investigation enhances insight into the interaction between sheets and dies, and provides a reference for the studying influence of dies on the forming limit of sheets in high-speed impaction deformation. [ABSTRACT FROM AUTHOR]

This paper investigates softening phenomena within the post-dynamic recrystallization (PDRX) process in 300M high-strength steel specimens with different initial dynamically recrystallized volume fractions. Isothermal, interrupted compression experiments were performed on a Gleeble-3500 at a temperature of 1273 K and strain rate of 0.01 s−1. To acquire different initial volume fractions of dynamically recrystallized (DRX) grains, deformation was interrupted at two strain levels and immediately followed by isothermal annealing treatments. The softening behaviors respectively caused by the static recrystallization (SRX) and metadynamic recrystallization (MDRX) were qualitatively characterized by variations in the mechanical properties of the deformed and recrystallized grains. On the basis of the Taylor dislocation model, the evolution of geometric necessary dislocations (GNDs) and statistically stored dislocations (SSDs) densities were also discussed to qualitatively clarify the nature of different softening behaviors. Results indicate that the SRX occurred alone in samples without initial DRX grains, after an incubation time of approximately 50 s, while MDRX initially appeared within 1 s and completed at about 8 s in samples with a high initial volume fraction of DRX grains. The microhardness, indentation hardness, and Young’s modulus in the deformed and recrystallized grains decreased gradually with an increase of MDRX and SRX volume fractions. The sink-in and pile-up phenomena were enhanced by the SRX and MDRX softening processes, respectively. The SSDs density decreased more noticeably during the MDRX process than that during the SRX, which indicates that the MDRX process contributed to a more significant softening effect within the microstructural evolution regimes. [ABSTRACT FROM AUTHOR]

• Fentanyl induced conditioned place preference (CPP) in mice. • L-THP attenuated the acquisition of fentanyl-induced CPP in mice. • Fentanyl induced upregulation of p-ERK and p-CREB in Hip, NAc, and PFC of mice. • L-THP decreased the upregulation of p-ERK and p-CREB in Hip, NAc, and PFC of mice. Levo-tetrahydropalmatine (L-THP) is the main active ingredient of Corydalis and Stephania and is widely used for its sedative, analgesic, and neuroleptic effects. Though L-THP is an antagonist of dopamine receptors and has been proven to be effective in treating drug addiction, its effect on fentanyl-induced reward learning still remains unclear. This experiment was designed to investigate the effects of L-THP on fentanyl-induced rewarding behavior through conditioned place preference (CPP) in mice. Western blot assays were used to dissect the accompanying changes in the phosphorylation of extracellular signal-regulated kinase (ERK) and cAMP response element binding protein (CREB) in related brain regions, including the hippocampus (Hip), caudate putamen (CPu), prefrontal cortex (PFC), and nucleus accumbens (NAc), which may mediate the effects of L-THP on fentanyl-induced CPP. The results revealed that fentanyl could induce CPP in mice at doses of 0.025 mg/kg, 0.05 mg/kg, 0.1 mg/kg, and 0.2 mg/kg, and L-THP could attenuate the acquisition of fentany-induced CPP at a dose of 10.0 mg/kg. The levels of p-ERK and p-CREB of the saline+fentanyl group (0.05 mg/kg) increased significantly in the Hip, NAc, and PFC compared to the saline+saline group. Furthermore, L-THP (10.0 mg/kg) co-administered with fentanyl during conditioning prevented the enhanced phosphorylation of ERK and CREB in the Hip, NAc, and PFC. Our research revealed that L-THP could suppress the rewarding properties of fentanyl-induced CPP, the inhibitory effect may be related to the suppression of ERK and CREB phosphorylation in the Hip, NAc, and PFC of mice. Thus, L-THP may have therapeutic potential for fentanyl addiction. [ABSTRACT FROM AUTHOR]

The metadynamic recrystallization (MDRX) behaviors and microstructure evolution of 300 M steel are studied by hot compression experiments and high temperature laser scanning confocal microscopy (HTLSCM) experiments. The effects of insulation temperature, pre-strain rate and holding time on the MDRX behaviors are discussed in detail. Based on the statistical results of the microstructure evolution, the MDRX kinetics model and recrystallization (RX) grain size model of 300 M steel are established, respectively. It can be confirmed from the in-situ observations that strain-induced boundary migration mechanism and curvature-driven grain boundary migration mechanism are the main MDRX mechanisms of 300 M steel. The MDRX develops rapidly under the high temperature or low pre-strain rate. The insulation temperature has a more important effect on the MDRX rate. The RX grain size increases with the increased insulation temperature, pre-strain rate and holding time. Compared to the pre-strain rate, the effects of insulation temperature on the maximum MDRX fraction and RX grain size are negligible. Comparisons between the experimental and predicted results verify that the proposed MDRX kinetics models and RX grain size model can quantificationally reveal the MDRX behaviors of 300 M steel well. • The MDRX behaviors are investigated by hot compression experiments and HTLSCM experiments. • The MDRX mechanisms are mainly strain-induced boundary migration and curvature-driven grain boundary migration. • The models for MDRX kinetics and RX grain size are established based on the statistic results of microstructure. • Insulation temperature affects MDRX rate obviously, while pre-strain rate affects maximum MDRX fraction apparently. [ABSTRACT FROM AUTHOR]

Introduction: As a central nervous system stimulant, methamphetamine (METH) can cause lasting changes after being abused, including possible changes of gene expression in the brain. The dopamine (DA) system plays a fundamental role in METH-induced behavioural changes, but the expression levels of various subtypes of DA receptors, especially the dopamine D3 receptor (D3R), remains unclear., Material and Methods: We explored the effect of the D3R on METH-induced behavioural sensitization by comparing D3R knockout (D3R-/-) mice with wild type (WT) mice. The quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression levels of the five DA receptor (D1R, D2R, D3R, D4R, and D5R) genes in four brain regions: the prefrontal cortex (PFc), nucleus accumbens (NAc), caudate-putamen (CPu), and hippocampus (Hip)., Results: The behavioural test results revealed that METH could induce behavioural sensitization both in WT and D3R-/- mice. Moreover, in D3R-/- mice, the increase in movement distance induced by methamphetamine was significantly less than that of wild-type mice. The response of the five DA receptors to METH exposure varies in different brain regions. To be more specific, METH increased the expression of the D3R gene in most brain regions of WT mice, decreased D1R and D2R gene expression both in the NAc and CPu of WT mice and in CPu of D3R-/- mice., Conclusions: These results suggested that D3R may play a positive regulatory role in the locomotor effects of METH, and five DA receptors, especially D1R, D2R, and D3R, may concurrently participate in the adaptive changes and the regulation of METH-induced behavioural sensitization.