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The traveling salesman problem (TSP) has been studied for many years. In particular, the multimodal optimization of the TSP is important for practical applications, because decision-makers can select the best candidate based on current conditions and requirements. In the Euclidean TSP, there are $n$ points in $\mathbb {R}^{d}$ space with Euclidean distance between any two points, that is, $d(x, y) =||x-y||_{2}$ . The goal is to find a tour of minimum length visiting each point. In this article, we only focus on the case that $d=2$ . Recently, in order to efficiently handle the multimodal optimization of the TSP, some methods have been developed to deal with it. Nevertheless, these methods usually perform poorly for large-scale cases. In this article, we propose a niching regression adaptive memetic algorithm (MA) to handle the multimodal optimization of the Euclidean TSP. We use the MA as the baseline algorithm and incorporate the neighborhood strategy to maintain the population diversity. In addition, we design a novel regression partition initialization and adaptive parameter control to enhance our algorithm, and propose the concept of the redundant individual to improve the search efficiency. To validate the performance of the proposed algorithm, we comprehensively conduct experiments on the multimodal optimization of TSP benchmark and the well-known TSPLIB library. The experimental results reveal that the proposed method outperforms other methods, especially for large-scale cases.

Tight sandstone reservoirs dominated by are developed in the Chang 6 oil layer group of the Yanchang Formation in the central-western part of the Ordos Basin. Featuring the lacustrine delta facies, Chang 6 formation in the center-west area of Ordos Basin shows an increasing petroleum reserve expectation. Its exploitation practice, however, has many problems caused by tight sandstone reservoir features. According to diagenetic and pore analysis, the diagenetic facies in the study area are grouped into four types: chlorite-film-intergranular-pore, feldspar-dissolution, clay-cemented-micropore, carbonate-cemented-tightness for their obvious differences in mineral feature and pore evolution. By introducing the comprehensive classification parameter synthesized from 9 other parameters, the reservoir quality is divided up into four levels: I(Feci> 1), II(3 ≤ Feci≤ 7), III(-2 ≤ Feci≤ 3), IV(Feci≤ -2). The reservoir quality division matches well with the diagenetic facies group. To decide the diagenetic type and reservoir quality division in all wells, the logging data are utilized with the Fisher discriminant method, which has obtained a good performance. The method enables the reservoir quality analysis expanding to all wells from samples, which is helpful for exploitation of the study area.

The Chang 7 oil group in the Ordos Basin has the characteristics of a tight lithology, a low formation pressure coefficient and strong reservoir heterogeneity. To better determine reasonable developmental technical countermeasures, oiliness, seepage capacity, and compressibility evaluations are combined. Using a combination of field practice and laboratory experiments, six types of sweetness classification evaluation parameters are screened: oil saturation, longitudinal oil layer structure coefficient, average pore throat radius, gas-oil ratio, brittleness index, and minimum horizontal principal stress. By combining the relationships among variables with the initial production from directional wells, the gray correlation method is used to quantify the weights of the contributions of evaluation parameters to production. On this basis, using the difference method for the curve slope, a sweetness evaluation and classification method for the Chang 7 oil group is constructed, and it solves the difficult problem of quality difference classification for the Chang 7 oil group and provides a reference basis for the optimal design of well patterns and fracturing reconstruction parameters.

As the continuous miniaturization of floating-gate transistors approaches a physical limit, new innovations in device architectures, working principles, and device materials are in high demand. This study demonstrated a nonvolatile memory structure with multilevel data storage that features a van der Waals gate architecture made up of a partially oxidized surface layer/indium selenide (InSe) van der Waals interface. The key functionality of this proof-of-concept device is provided through the generation of charge-trapping sites via an indirect oxygen plasma treatment on the InSe surface layer. In contrast to floating-gate nonvolatile memory, these sites have the ability to retain charge without the help of a gate dielectric. Together with the layered structure, the surface layer with charge-trapping sites facilitates continual electrostatic doping in the underlying InSe layers. The van der Waals gating effect is further supported by trapped charge-induced core-level energy shifts and relative work function variations obtained from operando scanning X-ray photoelectron spectroscopy and Kelvin probe microscopy, respectively. On modulating the amount of electric field-induced trapped electrons by the electrostatic gate potential, eight distinct storage states remained over 3000 s. Moreover, the device exhibits a high current switching ratio of 106within 11 cycles. The demonstrated characteristics suggest that the engineering of an InSe interface has potential applications for nonvolatile memory.

Byline: jian shi cortesi Saturday Arrive in Beijing with the aim of assessing whether it is a good time to increase exposure to China and if so, where to invest. [...]

Heterocyclic amines (HCAs), a class made up of more than 25 compounds, are unintended hazardous substances that are generated by the heating or processing of proteinaceous foods at high temperatures. The International Agency for Research on Cancer (IARC) has classified four such HCAs (IQ, MeIQ, MeIQx, and PhIP) as being probable or possible human carcinogens. In this study, two sample preparation strategies, liquid–liquid extraction (LLE) with solid-phase extraction (SPE) and a rapid, easy, cheap, effective, rugged, and safe extraction (QuEChERS) method, were investigated for the determination of 11 types of HCAs in meat products by LC-MS/MS. The HCAs in the samples were first extracted with acetonitrile by LLE, and followed by SPE. In the case of QuEChERS extraction, acetonitrile is used as the LLME solvent, and PSA, C18EC and MgSO4were used as the dSPE sorbent. Both methods showed good performance with respect to precision (RSD < 15.15%), accuracy (79.80–117.64%), recovery (52.39–116.88%), limit of quantitation for a spiked meat extract (0.01–10 ppb) and correlation coefficients (>0.993). The QuEChERS extraction strategy provided a better linear dynamic range and superior sensitivity in comparison with the LLE-SPE approach. HCAs were successfully quantified in real samples using the two proposed approaches by LC-MS/MS.

Potential exo‐specific [3+2] cascade cyclizations between o‐Br‐substituted cinnamates (CM−Br) and benzo‐fused 7‐oxa‐norbornadiene (Bz‐OND) by Pd‐mediated catalysis were explored both in racemic and asymmetric methods. A systematic study on Pd(II) catalysts, silane additives, carbonate bases, solvents, chiral diphosphines within a reaction temperature range of 60–80 °C were carried out. The best combination was between methyl o‐Br‐cinnamate and Bz‐OND catalyzed by Pd(OAc)2/dppf and /DM‐BINAP, respectively, in CH3CN at 80 °C. The desired racemic and optically active Bz‐OND‐fused indanes bearing 1‐carbonylmethylidene (CBM) unit were thus afforded in 95 % and 71 % yields and with enantioselectivities of up to 43 % ee. The optimal asymmetric recipe can be applied to alkyl, aryl cinnamates, 4‐substituted, and 5‐substituted o‐bromo‐cinnamates. Exclusive hydrogenations from the exo‐face of the CBM alkene units can be readily done by Pd(0)/charcoal in EtOAc, affording the product complementary to the direct Rh(I)‐catalyzed cyclization. A systematic studyof phosphine ligands, solvents, o‐bromo‐cinnamate esters was carried out for the [3+2] cyclization with benzo‐fused 7‐oxa‐norbornadiene (Bz‐OND). The best scenario involved the use of Pd(OAc)2and dppf or DM‐BINAP ligand, leading to highly Z‐selective synthesis of indane‐fused Bz‐OND with (RO2C)methylidene units. The target products were furnished with ee of up to 43 %.

Increased expression of microRNA 155 (miR-155) results in a decrease in endothelial nitric oxide synthase (eNOS) expression and impaired endothelial function. Factors that have been shown to increase expression of miR-155 may be mitigated by WS 1442, an extract of hawthorn leaves and flowers (Crataegus special extract) that contains a range of pharmacologically active substances including oligomeric proanthocyanidins and flavonoids. The purpose of this study is to determine the effect ofWS 1442 on the expression of miR-155 and eNOS in the presence of tumor necrosis factor (TNF-α). Human umbilical vein endothelial cells (HUVECs) were studied after the exposure to TNF-α, with or without simvastatin (positive control) and WS 1442. The expression levels of eNOS, phosphorylated eNOS, and miR-155 in the different HUVEC treatment groups were determined by western blot and quantitative real-time polymerase chain reaction, respectively. To evaluate the effect of WS 1442 on the eNOS activity, the medium and intracellular nitrate/nitrite (NO) concentrations were also analyzed using a colorimetric Griess assay kit. The results demonstrated that TNF-α upregulated miR-155 expression and decreased eNOS expression and NO concentrations. WS 1442 also increased miR-155 expression and decreased eNOS expression but, unlike TNF-α, increased phosphorylated eNOS expression and NO concentrations. Surprisingly, WS 1442 increased miR-155 expression; however, WS 1442 mitigated the overall negative effect of miR-155 on decreasing eNOS expression by increasing expression of phosphorylated eNOS and resulting in an increase in NO concentrations. In the setting where miR-155 may be expressed, WS 1442 may offer vascular protection by increasing the expression of phosphorylated eNOS. [ABSTRACT FROM AUTHOR]

Short QT syndrome (SQTS) is a genetic arrhythmogenic disease that can cause malignant arrhythmia and sudden cardiac death. The current therapies for SQTS have application restrictions. We previously found that Mg· (NH2CH2CH2SO3)2· H2O, a taurine-magnesium coordination compound (TMCC) exerted anti-arrhythmic effects with low toxicity. In this study we established 3 different models to assess the potential anti-arrhythmic effects of TMCC on type 2 short QT syndrome (SQT2). In Langendorff guinea pig-perfused hearts, perfusion of pinacidil (20 μmol/L) significantly shortened the QT interval and QTpeak and increased rTp-Te (P<0.05 vs control). Subsequently, perfusion of TMCC (1–4 mmol/L) dose-dependently increased the QT interval and QTpeak (P<0.01 vs pinacidil). TMCC perfusion also reversed the rTp-Te value to the normal range. In guinea pig ventricular myocytes, perfusion of trapidil (1 mmol/L) significantly shortened the action potential duration at 50% (APD50) and 90% repolarization (APD90), which was significantly reversed by TMCC (0.01–1 mmol/L, P<0.05 vs trapidil). In HEK293 cells that stably expressed the outward delayed rectifier potassium channels (IKs), perfusion of TMCC (0.01–1 mmol/L) dose-dependently inhibited the IKs current with an IC50value of 201.1 μmol/L. The present study provides evidence that TMCC can extend the repolarization period and inhibit the repolarizing current, IKs, thereby representing a therapeutic candidate for ventricular arrhythmia in SQT2.

Aiming at the paroxysmal fault of aircraft power system, this paper proposes a new method based on inverse problem of fuzzy optimization and deduces the corresponding fault diagnosis model. Firstly, establish the hybrid model of aircraft power system by Petri net. Secondly, analyze the relationship between fault symptoms and fault causes. Thirdly, combine the inverse problem with fuzzy diagnosis theory and get the inverse problem model of fuzzy optimization, the problem of diagnosis amounts to solving a fuzzy relational equation. Finally, solve the fuzzy relational equation by the numerical analysis method and do fault diagnosis by several fuzzy diagnosis rules. A case study demonstrates that the proposed model is feasible.

To provide the doctors a basis for treating sacral fractures and offer optimal surgical program, three-dimensional (3D) finite element method was used to simulate normal pelvis and the unstable pelvis sufferedIsection, IIsection and III section sacral fracture respectively.The unstable pelvises were respectively fixed with five different internal fixation implants types, which are respectively rectangular plate with cannulated screw, rectangular plate with solid screw, expansile bolt, convex plate with cannulated screw, convex plate with solid screw. The stress distribution and the X, Y, Z direction displacement of the sacrum were calculated for each sacral fracture treatment of five internal fixation implants after giving 500N axial load on lumbar vertebra and were compared with the normal pelvis, then the optimal surgery program were determined. After the analysis, by comparing the five combinations for each sacral fracture treatment of five internal fixation implants, the preferred combinations for the reset treatment of theIsection sacral fractures were rectangular plate with cannulated screw and convex plate with cannulated screw; The preferred combination for the reset treatment of the II section sacral fractures was expansile bolt; The preferred combination for the reset treatment of the III section sacral fractures was convex plate with cannulated screw.

Grinding, a technique for removing abrasive materials, is a chip-removal process that uses an individual abrasive grain as the cutting tool. Abrasive material removal processes can be very challenging owing to the high power requirements and the resulting high temperatures, especially at the workpiece-wheel interface. This paper presents a novel system that uses graphite particles impregnated in an aluminum oxide matrix to form a grinding wheel. This study specifically investigated grinding wheels with a graphite content of 0.5 wt%. The new grinding wheel was compared with conventional grinding wheels by comparing the factors of grinding performance, such as surface roughness, morphology, wheel wear ratio, grinding temperature, and grinding forces, when the wheels were used under two different coolant strategiesdry and with minimum quantity lubrication (MQL) using pure water. This study found that there is a considerable improvement in the grinding performance using graphite-impregnated grinding wheels over the performance obtained using conventional grinding wheels. The use of 0.5 wt% graphite provided better surface roughness and topography, lower grinding temperature, and decreased force; in addition, wheel consumption was lower, resulting in extended wheel life.

To explore the antifibrotic effect of echinacoside on carbon tetrachloride (CCl4)-induced hepatic fibrosis in rats.

To achieve safety commutation of the bidirectional switch in Matrix Sinusoidal waveform converter with high-frequency link, a decoupling time-driven strategy is proposed in this paper. The two gates in each bidirectional switch are driven by different signals, so the voltage surge caused by non-synchronous commutation of two bidirectional switches can be avoided, and both ZVS and ZCS are also achieved. Since the current polarity of load need not to be detected, the circuit is easy in realization. Experiments has been carried out to verify the feasibility of the proposed method.

Effective investigation attempts at the relationship between emotion and spatial design have been made in this paper which lists the significant impact of emotion upon interior design, emphasizes the emotional elements in design and advocates an emotional design concept. This paper pinpoints the goal of emotional design by demonstrating with examples the emotional characteristics and discusses the interplay between substance and the mind It seeks poetic residence design concepts and aims at interior design development toward the future.

Poly(3-dimethyl(methacryloyloxyethyl)ammonium propane sulfonate) (poly(DMAPS)) zwitterionic brushes were grafted onto the polycarbonateurethane (PCU) surface to improve its hydrophilicity and hemocompatibility by Ultraviolet (UV) polymerization. Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and water contact angle were used to characterize the chemical and physical properties of the modified PCU surface. DMAPS-grafted PCU films showed significantly high hydrophilicity owing to the high hydrophilic poly(DMAPS) zwitterionic brushes. The cytotoxicity tests revealed the sulfoammonium zwitterionic brushes modified PCU film had good cytocompatibility. In addition, the hemocompatibility of the modified PCU films was evaluated by hemolytic tests and platelet adhesion tests. The PCU films modified with zwitterionic brushes had a lower hemolytic index, showed effective resistance to platelet adhesion. Due to the fact that sulfoammonium zwitterionic brushes can improve the hemocompatibility of the PCU surface, this gives rise to its potential application as blood-contacting materials or devices.

In order to improve the hemocompatibility of polycarbonateurethane (PCU), the biomimetic phosphorylcholine (PC) group was introduced onto material surface. Brush structure having PC groups was formed by ultraviolet (UV) initiated polymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC) to improve the hydrophilicity and hemocompatibility of PCU surfaces. Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electrical microscopy (SEM) and water contact angle were used to characterize the chemical and physical properties of the modified PCU surfaces. Compared with original PCU, the PC-grafted PCU surfaces showed significantly high hydrophilicity as indicating by low water contact angle. The hemocompatibility of the PC-grafted PCU surfaces was evaluated by platelet adhesion test. The PCU surfaces modified with phosphorylcholine zwitterionic brushes showed effective resistance to platelet adhesion and high hemocompatibility. These PC-grafted PCU materials will have potential application as blood-contacting materials or devices due to their good mechanical and hemocompatible properties.

Taixi anthracite coal (TXC) was subjected to oxidation with NaOCl aqueous solution under mild conditions. The reaction mixture was extracted with ethoxyethane, followed by esterification with CH2N2, affording esterification products, which were analyzed by GC/MS. A large extent of benzene polycarboxylic acids (BPAs) were obtained in the coal oxidation products. The results showed that oxidation of coals with NaOCl aqueous solution is a useful technique for the high value-added utilization of coals.

Using solvents extraction separation system of self-designed make superior coal tar pitches for carbon materials. In proper order choose petroleum ether, methanol and carbon disulfide to cut coal tar into several fractions under different condition. The first solvent can take light components out from coal tar. Then drag out those chemical that contain heteroatom such as nitrogen, sulfide applying the second solvent. The last is to dig out higher molecular weight polycyclic aromatic hydrocarbon from coal tar deeply. Heavy fractions are vacuumed to drive out any solvents. The superior chirpy coal tar pitches for carbon materials acquired.

Multi-federation interconnected structure is the support structure that adapts to large-scale tactical communication network joint training. It needs to organize the distribution and transmission of various kinds of data effectively to assure high efficiency training. Aiming at the information distribution problem of multi-federation interconnected tactical communication network simulation training process, the single federation structure and multi-federation interconnected structure were brought out. Based on the region discerption of training scale and data classification of data, aiming at the characteristics of network traffic, networking parameters and operation state data, the specific solutions were proposed, so that the information distribution in the simulation training was optimized

A new two‐dimensional (2D) polymer, [Cu(pmt)(dca)]n[pmt = 2‐(2‐pyridymethylamino)ethanesulfonate, dca = dicyanamide] (1), was synthesized and characterized by single‐crystal X‐ray diffraction, elemental analysis, IR spectroscopy, and magnetic measurements. X‐ray structure analysis revealed that the compound contains [Cu(μ1,5‐dca)]nchains, which are further connected by bridging sulfonate anions of pmt ligands to result in (4,4)‐connected 2D sheets. The magnetic susceptibilities (2–300 K) of 1were investigated, and indicated that the complex exhibits a weak ferromagnetic interaction between the copper(II) ions.

. A Bulk RF MEMS switch is present in this paper. The beam structure and transmission line are separated fabricated on silicon and gallium arsenide (GaAs) wafer. The beam structure, up electrode, contact and anchor are fabricated on the silicon wafer. And transmission line and down electrode are made on the GaAs substrate. Two parts of the switch are bonded together by wafer bonding using gold layer as seed. The total area of the switch is 600 um X 600 um.

Abstract: The effect of ocean wave breaking as a non-Bragg mechanism on backscattering cross-section and modulation transfer functions (MTF) of radar was investigated based on Bragg resonance theory and parametric method. The result showed that the additional effect of wave breaking on backscattering cross-section is not more than 20% except for the small incident angle of VV polarized electromagnetic (e.m.) wave but is significant for HH polarized e.m. wave. Breaking waves lead to increase in the modulus of tilt modulation MTF and the larger the wind speed, the faster the increase. For large incident angle, the modulus of tilt modulation MTF with wave breaking decreases quickly with incident angle of HH polarization and approach to that without wave breaking for VV polarization. The hydrodynamic MTF increases 30%–60% when considering wave breaking and the increase is larger for HH polarization than for VV polarization.

In the grinding process of special spiral rods, the actual feed rate is far below the allowable limit, resulting in great efficiency waste. To tackle the problem, this paper presents a controlling strategy which significantly improves rough grinding efficiency through changing grinding feed rate, enhances work-piece surface quality and shortens the processing time. Based on the establishment of the work cycle model of the special spiral rod grinding process, the strategy sets the grinding efficiency of each individual rod section as the objective function, thus via genetic algorithm realizes an optimal calculation on grinding feed rate variable and resolves the power and roundness constraint problem. Through computer simulation, an optimal grinding control plan is obtained which can help the grinding process to achieve overall optimization.

Localized patterned visual stimulation was used in rats to investigate the feasibility of stimulus-dependent induction of the immediate early gene c-fos in neurons of cortical and subcortical visual centers of this mammal. Moving and stationary visual patterns, consisting of gratings and arrays of dark dots, induced Fos-like immunoreactivity in populations of neurons in retinotopically corresponding stimulated regions of the dorsal and ventral lateral geniculate nucleus (dLGN, vLGN), stratum griseum superficiale of the superior colliculus, nucleus of the optic tract, and primary (striate) visual cortex. Only moving stimuli induced Fos-like immunoreactive (FLI) neurons in extrastriate visual areas, particularly in the anterolateral (AL) visual area. This suggests that area AL is equivalent to the motion sensitive areas MT and PMLS of the monkey and cat. Stimulus-induced FLI neurons in the striate cortex were predominantly distributed in layers 4 and 6, while few labeled neurons were present in layers 2–3, and almost none in layer 5. The laminar distribution of stimulus-induced FLI cells in the extrastriate cortical area AL was similar to that of the striate cortex, with the exception that more FLI cells were present in layer 5. Statistical comparison of somata size of the stimulus-induced FLI neurons in dLGN with that of Cresyl violet stained neurons in the same sections revealed that the population of geniculate FLI neurons is composed of relay cells and interneurons.

In this paper, a strongly consistent estimation of the optimal trimming proportion in trimmed mean is found by the random weighting method. In addition, using the same method a strongly consistent estimation for the distribution of some adaptive estimator is also obtained.

Abstract: Two seismic refraction profiles which are perpendicular to each other, running through Xingtai earthquake region, reveal the anomalous variations of crust-mantle velocity structure and deep tectonics. Pg wave attenuates rapidly with distance in the earthquake region. A group of strong reflections from a depth of 21.0 km can be identified along the section from Longyao to the piedmont of Taihang Mountain, but Pm waves characterized generally by strong amplitude are not obvious. Under the earthquake region and its western neighboring region, the crustal velocity structure features high and low velocities changed alternatively. From North China plain to Shanxi plateau, the velocity at the top of the upper mantle decreases progressively, while crustal thickness increases by 11 km. Moho uplifts locally in the earthquake region. The crustal fault stretching deeply to Moho and the discontinuous sections of Moho in the earthquake region are supposed to be the channels and zones for magmatic intrusion. The uplifting of upper mantle and magmatic intrusion are responsible for the formation of anomalous crust-mantle structures and extending basins, and for the occurrence of Xingtai earthquake as well.

Abstract: In this paper, under some fairly general conditions, a first-order Edgeworth expansion for the standardized statistic of β in partial linear models is given, then a non-residual type of consistent estimation for the error variance is constructed, and finally an Edgeworth expansion for the corresponding studentized version is presented.

In the study of process semantics, trace equivalence and bisimulation equivalence constitute the two extremes of the so-called linear time--branching time spectrum . In this paper, we study the complexity and decidability issues of deciding trace and bisimulation equivalences for the model of systems with many identical processes with respect to various interprocess communication structures. In our model, each system consists of an arbitrary number of identical finite-state processes using Milner's calculus of communicating systems (CCS) as the style of interprocess communication. As it turns out, deciding trace and bisimulation equivalences are undecidable for star-like and linear systems, whereas the two problems are complete for PSPACE and PTIME, respectively, for fully connected systems.

A series of Cp2Ti(O2CC6H4X)2 complexes, where Cp = cyclopentadienyl, X = H, o-NO2, CH3, F, Cl, Br, I, NHAc, m-NO2, F, Cl, p-NO2, F, Cl, Br, OCH3 and 3,5-(NO2)2, have been synthesised and characterised on the basis of their elemental analysis, conductance measurements and spectral (IR and 1H NMR) studies. The effect of the substituent on the phenyl ring on the synthetic conditions is observed. The reactions of Cp2Ti(O2CPh)2 with some inorganic compounds, viz., HX (X = F, Cl, Br, I), SOCl2 and FeCl2 are also reported.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.