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We present a [Au7(SR)7] ring as a new type of protection ligand in a new atomic structure of Au15(SR)13 nanocluster for the first time based on the ring model developed to understand how interfacial interaction dictates the structures of protection motifs and gold cores in thiolate-protected gold nanoclusters. This new Au15(SR)13 model shows a tetrahedral Au4 core protected by one [Au7(SR)7] ring and two [Au2(SR)3] "staple" motifs. Density functional theory (DFT) calculations show that the newly predicted Au15(SR)13 (R = CH3/Ph) has a lower energy of 0.24/0.68 eV than previously proposed isomers. By comparing calculated optical absorption spectra (UV), circular dichroism (CD) spectra, and powder X-ray diffraction (XRD) patterns with related experimental spectra, the calculated CD spectra of the newly predicted Au15(SR)13 (R = CH3/Ph) cannot reproduce the experimental results, indicating that the newly predicted Au15(SR)13 is a new structure that needs to be confirmed by experiment. In addition, DFT calculations also show that the newly predicted Au15(SR)13 (R = CH3/Ph) exhibits a large HOMO-LUMO gap, suggesting its high chemical stability. The proposition of the [Au7(SR)7] ring as a protection ligand in the newly predicted Au15(SR)13 not only enriches the types of protection ligands in thiolate-protected gold nanoclusters but also further confirms the effectiveness and rationality of the ring model for understanding the interfacial interaction between the protection motifs and gold cores in thiolate-protected gold nanoclusters.

The atomic structures of 10-electron (10e) thiolate-protected gold nanoclusters have not received extensive attention both experimentally and theoretically. In this paper, five new atomic structures of 10e thiolate-protected gold nanoclusters, including three Au32(SR)22 isomers, one Au28(SR)18, and one Au33(SR)23, are theoretically predicted. Based on grand unified model (GUM), four Au17 cores with different morphologies can be obtained via three different packing modes of five tetrahedral Au4 units. Then, five complete structures of three Au32(SR)22 isomers, one Au28(SR)18, and one Au33(SR)23 isomers can be formed by adding the thiolate ligands to three Au17 cores based on the interfacial interaction between thiolate ligands and gold core in known gold nanoclusters. Density functional theory calculations show that the relative energies of three newly predicted Au32(SR)22 isomers are quite close to two previously reported isomers. In addition, five new 10e gold nanoclusters have large highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) gaps and all-positive harmonic vibration frequencies, indicating their high stabilities.

Power demand side management (DSM) regulations stipulate that electric power grid enterprises of cities and provinces must complete their target of power saving through efficient power plant (EPP) programs. This investigation studies power DSM and establishes a supervision and evaluation system for the EPP program. The proposed system can be used to evaluate the performance of an EPP program such as electricity saving and investment benefit. A model of EPP is established. A cuckoo search algorithm is applied for the model optimization and its result gives an optimal decision scheme. Finally, a fuzzy comprehensive evaluation method is used to assess an EPP program. The results show that the established supervision and evaluation system and the model of an EPP program are effective and applicable for power grid enterprises.

This paper discusses the origin and evolution of saline springs in north and central Laos, based on chemical and stable isotopes (δD, δ18O, δ11B, and δ37Cl). All the saline springs in this study are of the Na–Cl geochemical type. The geochemical and water isotope values suggest that the saline springs in this study are mainly derived from meteoric water and/or ice and snow melt from the surrounding mountains and that they also experienced strong evaporation and intense rock–water interactions. The ionic ratios, characteristic coefficients, ternary Ca–SO4–HCO3 phase diagrams, and saturation indices of minerals show that the dissolution of halite, sulfate, and carbonate rocks may be the solute sources for saline springs in this study, whereas the underground brines in the Thakhek potash mining area are geochemically influenced by the dissolution of carnallite and sylvite. The global geothermal δ11B–Cl/B relationship and δ11B values (5.50 to 36.01‰) of saline springs suggest a continental origin of B. This B is most likely derived from marine carbonate rocks and marine evaporates (gypsum and halite) of the late Cretaceous, which is similar to the saline springs of the Nangqen–Qamdo–Simao Salt Basin. The δ37Cl value (−0.12 to +0.79) and the Cl/Br ratio (4076 to 9853) show that dissolution of late cretaceous marine halite layers, atmospheric precipitation, and water–rock interactions between volcanic rocks, mudstones, and sandstone can restrict the δ37Cl values in saline springs. Results from silica geothermometry and multi–mineral equilibrium diagrams indicate that the reservoir temperatures for the saline springs range from 87–137 °C and experience deep circulation. Hydrochemical characteristic coefficients suggest that saline springs in the Muang Say basin may have leached sylvinite and carnallite and that the potash exploration prospect in this area is relatively good.

We present a [Au

In the process of oilfield development, the reservoir of oil wells were polluted due to well flushing and pump inspection, which resulted in long recovery period of oil well production after operation, or even difficult recovery of production. According to the states mentioned above, researchers developed XST and XSK series multifunctional flushing fluid, which had the function of anti-swelling, anti-pollution, as well as cleaning functions. The laboratory experiments showed that the oil washing efficiency ≥80%, anti-swelling rate ≥70%, as well as the damage value of reservoir permeability ≤30%. The above formula was applied in J902 oil well, which achieved great success. Not only the fishing tools went in smoothly, but also the recovery period after the well flushing operation was shortened to 4 days, which effectively reduced the impact of the well flushing operation on the well production.

Understanding the role of interfacial interactions between the protection motifs SR[Au(SR)]x (x = 0, 1, 2, 3, ...) and gold cores on the stabilities of the thiolate-protected gold nanoclusters is still a challenging task. Although several theoretical models, including the superatom complex, super valence bond, and superatom network, have provided insights into the stabilities of either the overall structures or the gold cores, a model that can illuminate how the interfacial interaction dictates the unique structures of the protection motifs and gold cores is still lacking. Herein, we present a ring model, on the basis of comprehensive analyses of all 95 previous experimentally crystallized and theoretically predicted thiolate-protected gold nanoclusters, to offer a deeper insight into the structure-interaction relationship for this class of clusters. In the ring model, all the thiolate-protected gold nanoclusters can be generically viewed as fusion or interlocking of several [Aum(SR)n] (m = 4 - 8, 10, 12, and 0 ≤ n ≤ m) rings. The aurophilic interactions among these rings are expected to play a key role in the stabilization of the thiolate-protected gold nanoclusters. Guided by the ring model and the grand unified model (for understanding the structures of gold cores), a new Au42(SR)26 isomer is predicted, whose total energy is even lower than those of two previously crystallized isomers, thereby giving credence to the predictability of the ring model. The ring model provides not only a mechanistic understanding of the interactions between the protection ligands and gold cores in the thiolate-protected gold nanoclusters, but also a practical guidance on predicting new thiolate-protected gold nanoclusters for experimental synthesis and confirmation.

This paper discusses the origin and evolution of saline springs in north and central Laos, based on chemical and stable isotopes (δD, δ18O, δ11B, and δ37Cl). All the saline springs in this study are of the Na–Cl geochemical type. The geochemical and water isotope values suggest that the saline springs in this study are mainly derived from meteoric water and/or ice and snow melt from the surrounding mountains and that they also experienced strong evaporation and intense rock–water interactions. The ionic ratios, characteristic coefficients, ternary Ca–SO4–HCO3 phase diagrams, and saturation indices of minerals show that the dissolution of halite, sulfate, and carbonate rocks may be the solute sources for saline springs in this study, whereas the underground brines in the Thakhek potash mining area are geochemically influenced by the dissolution of carnallite and sylvite. The global geothermal δ11B–Cl/B relationship and δ11B values (5.50 to 36.01‰) of saline springs suggest a continental origin of B. This B is most likely derived from marine carbonate rocks and marine evaporates (gypsum and halite) of the late Cretaceous, which is similar to the saline springs of the Nangqen–Qamdo–Simao Salt Basin. The δ37Cl value (−0.12 to +0.79) and the Cl/Br ratio (4076 to 9853) show that dissolution of late cretaceous marine halite layers, atmospheric precipitation, and water–rock interactions between volcanic rocks, mudstones, and sandstone can restrict the δ37Cl values in saline springs. Results from silica geothermometry and multi–mineral equilibrium diagrams indicate that the reservoir temperatures for the saline springs range from 87–137 °C and experience deep circulation. Hydrochemical characteristic coefficients suggest that saline springs in the Muang Say basin may have leached sylvinite and carnallite and that the potash exploration prospect in this area is relatively good.

Accurate and timely prediction of defect dimensions from magnetic flux leakage signals requires one to solve an inverse problem efficiently. This paper proposes a new inversing approach to such a problem. It combines cuckoo search (CS) and particle filter (PF) to estimate the defect profile from measured signals and adopts a radial-basis function neural network as a forward model as well as the observation equation in PF. As one of the latest nature-inspired heuristic optimization algorithms, CS can solve high-dimensional optimization problems. As an effective estimator for a nonlinear filtering problem, PF is applied to the proposed inversing approach in order to improve the latter’s robustness to the noise. The resulting algorithm enjoys the advantages of both CS and PF where CS produces the optimized state sequence for PF while PF processes the state sequence and estimates the desired profile. The simulation and experimental results have demonstrated that the proposed approach is significantly better than the inversing approach based on CS alone in a noisy environment.

In the process of oilfield development, the reservoir can be polluted by well cleaning, pump inspection and other operations. And that will lead to a long recovery period of oil well production after operation, and even the production is difficult to recover. In recent years, unplugging transformation and other technologies have been researched and applied, and certain results have been achieved. However, there is a lack of systematic evaluation and analysis on the applicability, advantages and disadvantages of various technologies. For this reason, the application effect of the existing technology is systematically analyzed and evaluated in terms of the formula of unplugging agent, unplugging process, damage mechanism, oil-water well relationship, production layer and other aspects by means of combination of geology and engineering. The adaptability of this technology is obtained, and it is used as the principle of well selection for subsequent technical application to further improve the effect of measures.

Dempster's combination rule can only be applied to independent bodies of evidence. One occurrence of dependence between two bodies of evidence is when they result from a common source. This paper proposes an improved method for combining dependent bodies of evidence which takes the significance of the common information sources into consideration. The method is based on the significance weighting operation and the "decombination" operation. A numerical example is illustrated to show the use and effectiveness of the proposed method.

In order to meet the higher accuracy and system reliability requirements, the information fusion for multi-sensor systems is an increasing concern. Dempster–Shafer evidence theory (D–S theory) has been investigated for many applications in multi-sensor information fusion due to its flexibility in uncertainty modeling. However, classical evidence theory assumes that the evidence is independent of each other, which is often unrealistic. Ignoring the relationship between the evidence may lead to unreasonable fusion results, and even lead to wrong decisions. This assumption severely prevents D–S evidence theory from practical application and further development. In this paper, an innovative evidence fusion model to deal with dependent evidence based on rank correlation coefficient is proposed. The model first uses rank correlation coefficient to measure the dependence degree between different evidence. Then, total discount coefficient is obtained based on the dependence degree, which also considers the impact of the reliability of evidence. Finally, the discount evidence fusion model is presented. An example is illustrated to show the use and effectiveness of the proposed method.

In this paper, efficient managing particle swarm optimization (EMPSO) for high dimension problem is proposed to estimate defect profile from magnetic flux leakage (MFL) signal. In the proposed EMPSO, in order to strengthen exchange of information among particles, particle pair model was built. For more efficient searching when facing different landscapes of problems, velocity updating scheme including three velocity updating models was also proposed. In addition, for more chances to search optimum solution out, automatic particle selection for re-initialization was implemented. The optimization results of six benchmark functions show EMPSO performs well when optimizing 100-D problems. The defect simulation results demonstrate that the inversing technique based on EMPSO outperforms the one based on self-learning particle swarm optimizer (SLPSO), and the estimated profiles are still close to the desired profiles with the presence of low noise in MFL signal. The results estimated from real MFL signal by EMPSO-based inversing technique also indicate that the algorithm is capable of providing an accurate solution of the defect profile with real signal. Both the simulation results and experiment results show the computing time of the EMPSO-based inversing technique is reduced by 20%–30% than that of the SLPSO-based inversing technique.

The mu opioid receptor (MOR) is known to play an essential role in morphine-induced analgesia. MOR-1 mRNA, the major MOR transcript, possesses a long 3′ untranslated region (3′UTR) in both mouse and human species. The sequence of the MOR-1 3′UTR, especially that of its 3′ end region, is conserved between mice and humans. In the MOR-1 3′UTR, AU-rich elements (AREs) are densely localized at the 3′ end region, suggesting low stability of this mRNA. Numerous putative transcription factor-binding motifs are located in the 3′ non-coding regions of the mouse and human MOR genes. The CXBK mouse strain, known as a MOR-deficient strain, possesses a decreased amount of MOR-1 mRNA containing an abnormally long MOR-1 3′UTR with a long nucleotide insertion. This insert might disrupt the stability of the MOR-1 mRNA or might reduce the transcription of the MOR-1 mRNA by separating the transcription factor-binding motifs in the 3′ non-coding region of the MOR gene, thereby decreasing MOR-1 mRNA expression and attenuating morphine-induced analgesia in CXBK mice. These recent findings suggest that the MOR-1 3′UTR is involved in mRNA expression and in the difference in response to morphine. This possible genetic mechanism may provide a good starting point for designing effective pain treatments with opiates.

This paper presents a genetic simulated annealing algorithm (GSAA)-based inverse algorithm for reconstructing the shape of a two-dimensional defect from the magnetic flux leakage (MFL) signals. In the algorithm, the GSAA formulated by incorporating the simulated annealing technique into the mutation operator of the standard genetic algorithm (GA) is employed to solve the optimization problem in the inverse problem, and a radial-basis function neural network (RBFNN) is utilized as the forward model. Experimental results demonstrated that the GSAA-based inverse algorithm is more accurate and is more robust to noise than the GA-based inverse algorithm.

The mu-opioid receptor (MOR) plays a mandatory role in the action of most opioid drugs, such as morphine, fentanyl, and heroin. It has been revealed that a deficiency in the MOR gene (Oprm1) or a difference in the 3' noncoding region of the gene markedly affects the sensitivity of mice to opioids. As the 3' noncoding region of the human OPRM1 gene had not yet been characterized, in the present study we conducted 3'-rapid amplification of cDNA ends (3'RACE)-PCR and identified the 3' end of the human MOR-1 mRNA, the most abundant transcript among OPRM1 gene transcripts. The poly(A) signal was located at 13612-13617 nucleotides downstream from the stop codon in the OPRM1 gene. Reverse transcription PCR analyses showed that the region from the stop codon to the poly(A) signal was transcribed. In the 3'UTR, we identified 33 AU-rich regions and more than 300 putative transcription factor-binding sites. Furthermore, we compared the 3' noncoding regions of the human and mouse OPRM1/Oprm1 genes and found apparent homology. In Northern blotting with mouse brain mRNAs, a same-size band was detected by a probe for the MOR-1 coding region and by a probe for a mouse genome region corresponding to the human MOR-1 3'UTR. Since 3'UTRs affect gene expression, the present characterization of the 3' noncoding region in the human OPRM1 gene should lead to a better understanding of the mechanisms underlying OPRM1 gene regulation and individual differences in sensitivity to opioids.

Magnetic flux leakage (MFL) inspection is one of the most important and sensitive nondestructive testing approaches. For online MFL inspection of a long-range railway track or oil pipeline, a fast and effective defect profile estimating method based on a multi-power affine projection algorithm (MAPA) is proposed, where the depth of a sampling point is related with not only the MFL signals before it, but also the ones after it, and all of the sampling points related to one point appear as serials or multi-power. Defect profile estimation has two steps: regulating a weight vector in an MAPA filter and estimating a defect profile with the MAPA filter. Both simulation and experimental data are used to test the performance of the proposed method. The results demonstrate that the proposed method exhibits high speed while maintaining the estimated profiles clearly close to the desired ones in a noisy environment, thereby meeting the demand of accurate online inspection.

The importance of voltage-dependent Ca2+ channels (VDCCs) in pain transmission has been noticed gradually, as several VDCC blockers have been shown to be effective in inhibiting this process. In particular, the N-type VDCC has attracted attention, because inhibitors of this channel are effective in various aspects of pain-related phenomena. To understand the genuine contribution of the N-type VDCC to the pain transmission system, we generated mice deficient in this channel by gene targeting. We report here that mice lacking N-type VDCCs show suppressed responses to a painful stimulus that induces inflammation and show markedly reduced symptoms of neuropathic pain, which is caused by nerve injury and is known to be difficult to treat by currently available therapeutic methods. This finding clearly demonstrates that the N-type VDCC is essential for development of neuropathic pain and, therefore, controlling the activity of this channel can be of great importance for the management of neuropathic pain.

α 1 subunit of the voltage-dependent Ca 2+ channel is essential for channel function and determines the functional specificity of various channel types. α 1E subunit was originally identified as a neuron-specific one, but the physiological function of the Ca 2+ channel containing this subunit (α 1E Ca 2+ channel) was not clear compared with other types of Ca 2+ channels because of the limited availability of specific blockers. To clarify the physiological roles of the α 1E Ca 2+ channel, we have generated α 1E mutant (α 1E −/−) mice by gene targeting. The lacZ gene was inserted in-frame and used as a marker for α 1E subunit expression. α 1E −/− mice showed reduced spontaneous locomotor activities and signs of timidness, but other general behaviors were apparently normal. As involvement of α 1E in pain transmission was suggested by localization analyses with 5-bromo-4-chloro-3-indolyl β- d -galactopyranoside staining, we conducted several pain-related behavioral tests using the mutant mice. Although α 1E +/− and α 1E −/− mice exhibited normal pain behaviors against acute mechanical, thermal, and chemical stimuli, they both showed reduced responses to somatic inflammatory pain. α 1E +/− mice showed reduced response to visceral inflammatory pain, whereas α 1E −/− mice showed apparently normal response compared with that of wild-type mice. Furthermore, α 1E −/− mice that had been presensitized with a visceral noxious conditioning stimulus showed increased responses to a somatic inflammatory pain, in marked contrast with the wild-type mice in which long-lasting effects of descending antinociceptive pathway were predominant. These results suggest that the α 1E Ca 2 + channel controls pain behaviors by both spinal and supraspinal mechanisms.

BACKGROUND: The inducible cyclic adenosine monophosphate (cAMP) early repressor (ICER) is highly expressed in the central nervous system and functions as a repressor of cAMP response element-binding protein (CREB) transcription. The present study sought to clarify the role of ICER in the effects of methamphetamine (METH). METHODS AND FINDINGS: We tested METH-induced locomotor sensitization in wildtype mice, ICER knockout mice, and ICER I-overexpressing mice. Both ICER wildtype mice and knockout mice displayed increased locomotor activity after continuous injections of METH. However, ICER knockout mice displayed a tendency toward higher locomotor activity compared with wildtype mice, although no significant difference was observed between the two genotypes. Moreover, compared with wildtype mice, ICER I-overexpressing mice displayed a significant decrease in METH-induced locomotor sensitization. Furthermore, Western blot analysis and quantitative real-time reverse transcription polymerase chain reaction demonstrated that ICER overexpression abolished the METH-induced increase in CREB expression and repressed cocaine- and amphetamine-regulated transcript (CART) and prodynorphin (Pdyn) expression in mice. The decreased CART and Pdyn mRNA expression levels in vivo may underlie the inhibitory role of ICER in METH-induced locomotor sensitization. CONCLUSIONS: Our data suggest that ICER plays an inhibitory role in METH-induced locomotor sensitization.

Phencyclidine (PCP), a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist, increases locomotor activity in rodents and causes schizophrenia-like symptoms in humans. Although activation of the dopamine (DA) pathway is hypothesized to mediate these effects of PCP, the precise mechanisms by which PCP induces its effects remain to be elucidated. The present study investigated the effect of PCP on extracellular levels of DA (DA(ex)) in the striatum and prefrontal cortex (PFC) using in vivo microdialysis in mice lacking the NMDA receptor channel ε1 or ε4 subunit (GluRε1 [GluN2A] or GluRε4 [GluN2D]) and locomotor activity. PCP significantly increased DA(ex) in wildtype and GluRε1 knockout mice, but not in GluRε4 knockout mice, in the striatum and PFC. Acute and repeated administration of PCP did not increase locomotor activity in GluRε4 knockout mice. The present results suggest that PCP enhances dopaminergic transmission and increases locomotor activity by acting at GluRε4.