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In the past decade, regularization methods for system identification have attracted a great deal of attention in the system identification community. For regularization method with regularization in quadratic form, there are different ways to design the regularization, e.g., through designing a positive semidefinite kernel or a filter. In this paper, we propose a new regularization method, where the regularization is in essence induced by simulating a carefully designed linear system driven by a white Gaussian noise and this regularization method is thus called the simulation-induced regularization method (SIRM). In contrast with the kernel or filter based regularization methods, SIRM has the advantages that it is free of the explicit expression of the regularization and moreover, has a linear computational complexity.

User-generated contents (UGCs) on social media are a valuable source of emergency information (EI) that can facilitate emergency responses. However, the tremendous amount and heterogeneous quality of social media UGCs make it difficult to extract truly useful EI, especially using pure machine learning methods. Hence, this study proposes a machine learning and rule-based integration method (MRIM) and evaluates its EI classification performance and determinants. Through comparative experiments on microblog data about the “July 20 heavy rainstorm in Zhengzhou” posted on China’s largest social media platform, we find that the MRIM performs better than pure machine learning methods and pure rule-based methods, and that its performance is influenced by microblog characteristics such as the number of words, exact address and contact information, and users’ attention. This study demonstrates the feasibility of integrating machine learning and rule-based methods to mine the text of social media UGCs and provides actionable suggestions for emergency information management practitioners.

The crushing is a crucial unit operation for recycling waste printed circuit boards. In this study, dimethylacetamide was used to improve the crushing efficiency of waste printed circuit boards. The sectional morphology of the printed circuit boards was observed by scanning electron microscopy after a swelling treatment, the result showed the metal-nonmetal interface appeared noticeable cracks. The mechanical properties of material was measured by dynamometer, the results indicated that the destructive load of treated printed circuit boards was reduced by 115.32 N. The yield and metal grade of the crushed products were determined for each fraction. For the −0.074 mm fraction, the swelling treatment reduced the yield by 8.19% versus the regular treatment. For the −0.5 + 0.25 mm fraction, the grade of copper was increased by 7.35% after the swelling treatment. In addition, the main trace elements of the electrical components can be enriched in the coarse fraction. An analysis of the infrared spectra of the organic solvent before and after the swelling treatment revealed that the compositions of the organic solvent and the resins remained unchanged with this treatment. The swelling process of printed circuit boards was illustrated by the non-uniform effects of thermal expansion of materials and the interaction of organic solvent with nonmetal. Further, the hydrogen bonds between the dimethylacetamide and the resin molecules were expressed by a molecular structure diagram. Overall, this method can achieve metal liberation and enrichment in the coarse fraction, reducing the generation of fine particles and organic solvent can also be recycled. Thus, this study provides an alternative approach to improve the crushing efficiency of waste printed circuit boards.

Rewarding memories induced by addictive drugs may contribute to persistent drug-seeking behaviors, which is an important contributing factor to drug addiction. However, the biological mechanisms underlying drug-associated rewarding memories have not yet been fully understood, especially the new synthetic drugs, such as amphetamine-type stimulants (ATS). In this study, using the rat-conditioned place preference (CPP) model, a classic animal model for the reward-associated effects of addictive drugs, we found that the expression level of GABAA α1 subunits was significantly decreased in the dorsal striatum (Dstr) after conditioned methamphetamine (METH) pairing, and no significant differences were observed in the other four rewarding memory-associated areas (medial prefrontal cortex (mPFC), nucleus accumbens (NAc), amygdala (Amy), and dorsal hippocampus (DH)). Intra-Dstr injection of either the GABAA receptor agonist muscimol or the specific α1GABAA receptor-preferring benzodiazepine (BDZ) agonist zolpidem significantly abolished METH CPP formation. Thus, this study extends previous findings by showing that GABAA receptors, particularly the α1-containing GABAA receptors, may be strongly implicated in METH-associated rewarding memories. This work provides us with a new perspective on the goal of treating ATS addiction.

We present a study of charm and beauty isolation based on a data-driven method with recent measurements on heavy flavor hadrons and their decay electrons in Au+Au collisions at s NN = 200 GeV at RHIC. The individual electron p T spectra, R AA and v 2 distributions from charmed and beauty hadron decays are obtained. We find that the electron R AA from beauty hadron decays ( R AA b → e ) is suppressed in minimum bias Au+Au collisions but less suppressed compared with that from charmed hadron decays at p T > 3.5 GeV/c, which indicates that beauty quark interacts with the hot-dense medium with depositing its energy and is consistent with the mass-dependent energy loss scenario. For the first time, the non-zero electron v 2 from beauty hadron decays ( v 2 b → e ) at p T > 3.0 GeV/c is observed and shows smaller elliptic flow compared with that from charmed hadron decays at p T p T v 2 b → e is smaller than a number-of-constituent-quark (NCQ) scaling hypothesis. This suggests that beauty quark is unlikely thermalized and too heavy to be moved in a partonic collectivity in heavy-ion collisions at the RHIC energy.

Summary Objectives MicroRNA (miRNA) machinery regulates cancer cell behavior, and has been implicated in patients’ clinical status and prognosis. We found that microRNA-29b (miR-29b) increased significantly in advanced migratory cells. However, miR-29b controls the migration ability, and its regulatory mechanism in oral squamous cell carcinoma (OSCC) remains unknown. Materials and methods We triggered miR-29b expression in OSCC patients and cell lines by conducting real-time quantitative PCR. We determined the functions of miR-29b in the migration of OSCC cells by using gain- and loss-of-function approaches. We elevated the target genes of miR29b through software predictions and a luciferase report assay. We used an orthotopic OSCC animal model to investigate the effects of miR29b on OSCC cell metastasis in vivo. Results The clinical data revealed that miR-29b expression was correlated with lymph node metastasis and an advanced tumor stage in 98 OSCC patients. Furthermore, multivariate analysis revealed that miR-29b expression was significantly correlated with recurrence, and indicated poor survival. MiR-29b promoted OSCC cell migration and downregulated CX3CL1, a cell–cell adhesion regulator, which plays an essential role in miR-29b-regulated OSCC cell migration machinery. Furthermore, we found that CX3CL1 expression was correlated with lymph node metastasis and an early tumor stage in OSCC patients, and negatively correlated with miR-29b expression. Conclusion MiR-29b acts as an oncomir, promoting cell migration through CX3CL1 suppression, and could be a potential therapeutic target for preventing OSCC progression.

Uniform football-like anatase TiO2 particles exposed by {0 0 1} facets were successfully synthesized by an environment-friendly, facile and low-temperature hydrothermal method in water solution without any additional capping agent. The crystallographic structure and the growth mechanism of anatase TiO2 particles were investigated systematically by X-ray diffraction pattern (XRD), field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectra (XPS), respectively. The formation mechanism of football-like anatase TiO2 particles exposed by {0 0 1} facets is investigated. It was found that there existed a selective adsorption of F− ions on different facets by analyzed with the density functional theory (DFT) computer simulation results, and it would lead to a selective nucleation and crystal growth of anatase football-like TiO2 particles. Additionally, this type of exposed {0 0 1} facets football-like TiO2 microspheres were used as a scattering overlayer on a transparent P25 film for fabrication of photoanodes for dye-sensitized solar cells (DSSCs). The results showed that an overall light conversion efficiency of this film was 6.31%, which is higher than that of the overall efficiency (5.13%) obtained from the P25 photoanode owing to the superior light scattering effect of microspheres and excellent light reflecting ability of the mirror-like plane {0 0 1} facets.

XRD measurements were conducted on an α + β Mg–10.2Li–1.2Al–0.4Zn (LAZ1010) alloy. In 80% cold-rolled plate, strong (0 0 0 2) α peak intensity is found on the rolling plane, and 2 θ values of θ–MgLi 2 Al peaks are shifted slightly to higher angle, indicating that Mg atoms in θ phase are partly replaced by Al atoms during severe cold-rolling. Solid–solution treated specimens aged at room temperature reach the maximal hardness after ≈20 h of aging. XRD tests show that θ precipitates is much smaller in size than α ones, which may be attributed to the hardening phenomenon observed in the solid–solution treated and aged LAZ1010 alloy. During aging, the decrease in hardness of solid–solution treated specimens with severe cold-rolling at its maximal hardness is slower than that without. It is because specimens with severe cold-rolling have abundant nucleus sites and thus have θ precipitates of smaller size.

Flexible organic light-emitting devices (FOLEDs) based on multiple quantum well (MQW) structures, which consist of alternate layers of 2,3,5,6-Tetrafluoro-7,7,8,8,-tetracyano-quinodimethane (F4-TCNQ) and 4,4′,4″-tris-(3-methylphenylphe-nylamino)tripheny-lamine (m-MTDATA) have been fabricated. The Alq 3 -based device with double quantum well (DQW) structure exhibits the remarkable electroluminescent (EL) performances for the brightness of 23,500 cd/m 2 at 14 V and the maximum current efficiency of 7.0 cd/A at 300.3 mA/cm 2 , respectively, which are greatly improved by 114% and 56% compared with the brightness of 10,958 cd/m 2 at 14 V and the maximum current efficiency of 4.5 cd/A at 174.0 mA/cm 2 for the conventional device without MQW structures. These results demonstrate that the EL performances of FOLEDs could be greatly improved by utilizing the novel MQW structures, and the reason for this improvement has also been explained by the effect of interfacial dipole and interfacial doping between F4-TCNQ and m-MTDATA in this article.

Fuzzy association rules (FARs) can be powerful in assessing regional soil quality, a critical step prior to land planning and utilization; however, traditional FARs mined from soil quality database, ignoring the importance variability of the rules, can be redundant and far from optimal. In this study, we developed a method applying different weights to traditional FARs to improve accuracy of soil quality assessment. After the FARs for soil quality assessment were mined, redundant rules were eliminated according to whether the rules were significant or not in reducing the complexity of the soil quality assessment models and in improving the comprehensibility of FARs. The global weights, each representing the importance of a FAR in soil quality assessment, were then introduced and refined using a gradient descent optimization method. This method was applied to the assessment of soil resources conditions in Guangdong Province, China. The new approach had an accuracy of 87%, when 15 rules were mined, as compared with 76% from the traditional approach. The accuracy increased to 96% when 32 rules were mined, in contrast to 88% from the traditional approach. These results demonstrated an improved comprehensibility of FARs and a high accuracy of the proposed method.

Land evaluation factors often contain continuous-, discrete- and nominal-valued attributes. In traditional land evaluation, these different attributes are usually graded into categorical indexes by land resource experts, and the evaluation results rely heavily on experts' experiences. In order to overcome the shortcoming, we presented a fuzzy neural network ensemble method that did not require grading the evaluation factors into categorical indexes and could evaluate land resources by using the three kinds of attribute values directly. A fuzzy back propagation neural network (BPNN), a fuzzy radial basis function neural network (RBFNN), a fuzzy BPNN ensemble, and a fuzzy RBFNN ensemble were used to evaluate the land resources in Guangdong Province. The evaluation results by using the fuzzy BPNN ensemble and the fuzzy RBFNN ensemble were much better than those by using the single fuzzy BPNN and the single fuzzy RBFNN, and the error rate of the single fuzzy RBFNN or fuzzy RBFNN ensemble was lower than that of the single fuzzy BPNN or fuzzy BPNN ensemble, respectively. By using the fuzzy neural network ensembles, the validity of land resource evaluation was improved and reliance on land evaluators' experiences was considerably reduced.

In this paper, an adaptive fuzzy control method is presented to synchronize model-unknown discrete-time generalized Henon map. The proposed method is robust to approximate errors and disturbances, because it integrates the merits of adaptive fuzzy and the variable structure control. Moreover, it can realize the synchronizations of non-identical chaotic systems. The simulation results of synchronization of generalized Henon map show that it not only can synchronize model-unknown generalized Henon map but also is robust against the noise of the systems. These merits are advantageous for engineering realization.

A discrete-time adaptive fuzzy control scheme is presented to synchronize model-unknown coupled Henon-map lattices (CHMLs). The proposed method is robust to approximate errors, parameter mismatches and disturbances, because it integrates the merits of the adaptive fuzzy systems and the variable structure control with a sector. The simulation results of synchronization of CHMLs show that it not only can synchronize model-unknown CHMLs but also is robust against parameter mismatches and noise of the systems. These merits are advantageous for engineering realization.

Pyrophosphate-dependent phosphofructokinase (PPi-PFK) was identified previously in Toxoplasma gondii as the only kinase that phosphorylates fructose-6-P to fructose-1,6-bisP. Since such an enzyme is not present in mammals, it was considered to be a good target for prospective selective inhibitors of the parasite. We have examined the effects of several phosphonic acid derivatives, analogs of pyrophosphate, on PPi-PFK activity, as well as on the replication of T. gondii in human foreskin fibroblast (HFF) cells. The most active compound in inhibiting PPi-PFK was tetrasodium carbonyldiphosphonate. Several bisphosphonates and related arylhydrazones showed inhibition of the enzyme, but with higher IC50 values. Although several phosphonoacetic acid derivatives also inhibited PPi-PFK, as a group they were less potent than the bisphosphonate derivatives. Comparison among the structures of various inhibitors and their effects against PPi-PFK indicates that a carbonyl (C=O) or amino (C=N) group between two phosphoryl moieties is associated with more potent enzyme inhibiton. Tetrasodium carbonyldiphosphonate did not show a significant effect against replication of T. gondii cells, probably because, as a charged molecule, it could not cross the cell membrane to reach the intracellular parasite. Tetraisopropyl carbonyldiphosphonate 2,4-dinitrophenylhydrazone showed some selective inhibitory effect against replication of the parasite in the HFF cells and protected the mammalian cells from damage by T. gondii. The results indicate that carbonyldiphosphonic acid is a good prototype compound that is amenable to chemical manipulation, which, in turn, may optimize selective inhibition of T. gondii PPi-PFK and increase accessibility to the intracellular parasite.

The Hall effect study has been performed to examine the nature of quasi-particles of electron-doped superconductor, T′-phase La2−xCexCuO4 (LCCO) thin films with 0.06 ⩽ x ⩽ 0.17 , for which the superconductivity is quenched by magnetic fields (up to 12 T) at temperature well below T c . The data distinctly show the evolution of the role of electron-like and hole-like quasi-particles in Fermi surface which dominate the superconductivity and normal state transport.