Design and platform testing of the compact torus central fueling device for the EAST tokamak

Compact torus(CT)injection is a highly promising technique for the central fueling of future reactor-grade fusion devices since it features extremely high injection velocity and relatively high plasma mass.Recently,a CT injector for the EAST tokamak,EAST-CTI,was developed and platform-tested.In the first round of experiments conducted with low parameter settings,the maximum velocity and mass of the CT plasma were 150 km·s^(-1)and 90μg,respectively.However,the parameters obtained by EAST-CTI were still very low and were far from the requirements of a device such as EAST that has a strong magnetic field.In future,we plan to solve the spark problem that EAST-CTI currently encounters(that mainly hinders the further development of experiments)through engineering methods,and use greater power to obtain a more stable and suitable CT plasma for EAST.

Optimal Design and Force Control of a Nine-Cable-Driven Parallel Mechanism for Lunar Takeoff Simulation

Traditional simulation methods are unable to meet the requirements of lunar takeo simulations, such as high force output precision, low cost, and repeated use. Considering that cable-driven parallel mechanisms have the advantages of high payload to weight ratio, potentially large workspace, and high-speed motion, these mechanisms have the potential to be used for lunar takeo simulations. Thus, this paper presents a parallel mechanism driven by nine cables. The purpose of this study is to optimize the dimensions of the cable-driven parallel mechanism to meet dynamic workspace requirements under cable tension constraints. The dynamic workspace requirements are derived from the kinematical function requests of the lunar takeo simulation equipment. Experimental design and response surface methods are adopted for building the surrogate mathematical model linking the optimal variables and the optimization indices. A set of dimensional parameters are determined by analyzing the surrogate mathematical model. The volume of the dynamic workspace increased by 46% after optimization. Besides, a force control method is proposed for calculating output vector and sinusoidal forces. A force control loop is introduced into the traditional position control loop to adjust the cable force precisely, while controlling the cable length. The e ectiveness of the proposed control method is verified through experiments. A 5% vector output accuracy and 12 Hz undulation force output can be realized. This paper proposes a cable-driven parallel mechanism which can be used for lunar takeo simulation.

Microbiostratigraphy, microfacies and sequence stratigraphy of upper cretaceous and paleogene sediments, Hendijan oilfield, Northwest of Persian Gulf, Iran

Hendijan oilfield is located on Northwest of Pesian Gulf offshore of Iran and geologically in the Dezful embayment. In this study, the paleosedimentary depositional environment of the Early Cenomanian to Late Eocene deposits of the Sarvak, Ilam, Gurpi, Pabdeh and JahrumPabdeh Formations was evaluated using microbiostratigraphy, microfacies and D-INPEFA curves which are an accurate method in sequence stratigraphy in terms of regression and transgression of the sea. Also, we used limited elemental geochemical data of oxygen and carbon isotopes in compare with palaeontological data to infer the upper part, 10 m, of the Sarvak Formation. Statistical correlation analyses of geochemical data from upper part of the Sarvak Formation enable inference of differences in paleoconditions at this part and Sarvak Formation, and another Formation, Ilam, was distinguished. Palaentilogical analysis using planktonic foraminifera and calcareous nannofossils enables inference about time scale of each Formation. Petrographic data and different sediment textures support those inferences resulted from Gamma ray logs as D-INPEFA curves about different paleo-conditions that occurred during the development of the studied Formations. Synthesis of the analyses leads to the final interpretation that upper Cretaceous, Sarvak, Ilam and Gurpi Formations, at the Hendijan oil field were formed in a carbonate ramp that was likely closed to the open sea, where Gurpi Formation was deposited, by a shallow barrier that allowed seawater recharge into the basin and deep marine basin where Paleogene sediments, Pabdeh and Jahrum-Pabdeh, were deposited.

Investigation of the compact torus plasma motion in the KTX-CTI device based on circuit analyses

Compact torus(CT)injection is one of the most promising methods for the central fuelling of next-generation reactor-grade fusion devices due to its high density,high velocity,and selfcontained magnetised structure.A newly compact torus injector(CTI)device in Keda Torus e Xperiment(KTX),named KTX-CTI,was successfully developed and tested at the University of Science and Technology in China.In this study,first,we briefly introduce the basic principles and structure of KTX-CTI,and then,present an accurate circuit model that relies on nonlinear regression analysis(NRA)for studying the current waveform of the formation region.The current waveform,displacement,and velocity of CT plasma in the acceleration region are calculated using this NRA-based one-dimensional point model.The model results were in good agreement with the experiments.The next-step upgrading reference scheme of the KTX-CTI device is preliminarily investigated using this NRA-based point model.This research can provide insights for the development of experiments and future upgrades of the device.

Fail-Safe Topology Optimization of Continuum Structures with Multiple Constraints Based on ICM Method

Traditional topology optimization methods may lead to a great reduction in the redundancy of the optimized structure due to unexpected material removal at the critical components.The local failure in critical components can instantly cause the overall failure in the structure.More and more scholars have taken the fail-safe design into consideration when conducting topology optimization.A lot of good designs have been obtained in their research,though limited regarding minimizing structural compliance(maximizing stiffness)with given amount of material.In terms of practical engineering applications considering fail-safe design,it is more meaningful to seek for the lightweight structure with enough stiffness to resist various component failures and/or to meet multiple design requirements,than the stiffest structure only.Thus,this paper presents a fail-safe topology optimization model for minimizing structural weight with respect to stress and displacement constraints.The optimization problem is solved by utilizing the independent continuous mapping(ICM)method combined with the dual sequence quadratic programming(DSQP)algorithm.Special treatments are applied to the constraints,including converting local stress constraints into a global structural strain energy constraint and expressing the displacement constraint explicitly with approximations.All of the constraints are nondimensionalized to avoid numerical instability caused by great differences in constraint magnitudes.The optimized results exhibit more complex topological configurations and higher redundancy to resist local failures than the traditional optimization designs.This paper also shows how to find the worst failure region,which can be a good reference for designers in engineering.

New Results on Oscillation of even Order Neutral Differential Equations with Deviating Arguments

In this paper, we point out some small mistakes in [6] and revise them, we obtain some new oscillation results for certain even order neutral differential equations with deviating arguments. Our results extend and improve many known oscillation criteria because the article just generalizes Meng and Xu’s results.

A bHLH transcription activator regulates defense signaling by nucleo-cytosolic trafficking in rice

Crosstalk between plant hormone signaling pathways is vital for controlling the immune response during pathogen invasion.Salicylic acid(SA)and jas-monic acid(JA)often play important but antagonistic roles in the immune responses of higher plants.Here,we identify a basic helix-loop-helix transcription acti-vator,OsbHLH6,which confers disease resistance in rice by regulating SA and JA signaling via nucleo-cytosolic trafficking in rice(Oryza sativa).OsbHLH6 expression was upregulated during Magnaporthe oryzae infection.Transgenic rice plants overexpressing OsbHLH6 display increased JA responsive gene expression and enhanced disease susceptibility to the pathogen.Nucleus-localized OsbHLH6 activates JA signaling and suppresses SA signaling;however,the SA regulator OsNPR1(Nonexpressor of PR genes 1)sequesters OsbHLH6 in the cytosol to alleviate its effect.Our data suggest that OsbHLH6 controls disease re-sistance by dynamically regulating SA and JA signaling.

Brain of the blind:transcriptomics of the golden-line cavefish brain

The genus Sinocyclocheilus (golden-line barbel) includes 25species of cave-dwelling blind fish (cavefish)and more than 30 surface-dwelling species with normal vision.Cave environments are dark and generally nutrient-poor with few predators.Cavefish of several genera evolved convergent morphological adaptations in visual,pigmentation,brain,olfactory,and digestive systems. We compared brain morphology and gene expression patterns in a cavefish Sinocyclocheilus anophthalmus with those of a closely related surface-dwelling species S.angustiporus.Results showed that cavefish have a longer olfactory tract and a much smaller optic tectum than surface fish.Transcriptomics by RNA-seq revealed that many genes upregulated in cavefish are related to lysosomes and the degradation and metabolism of proteins,amino acids,and lipids.Genes down- regulated in cavefish tended to involve "activation of gene expression in cholesterol biosynthesis" and cholesterol degradation in the brain.Genes encoding Srebfs (sterol regulatory element- binding transcription factors)and Srebf targets,including enzymes in cholesterol synthesis,were downregulated in cavefish brains compared with surface fish brains.The gene encoding Cyp46a1, which eliminates cholesterol from the brain,was also downregulated in cavefish brains,while the total level of cholesterol in the brain remained unchanged.Cavefish brains misexpressed several genes encoding proteins in the hypothalamus-pituitary axis,including Trh,Sst,Crh,Pomc,and Mc4r.These results suggest that the rate of lipid biosynthesis and breakdown may both be depressed in golden-line cavefish brains but that the lysosome recycling rate may be increased in cavefish;properties that might be related to differences in nutrient availability in caves.

Differentially-expressed opsin genes identified in Sinocyclocheilus cavefish endemic to China

Eye degeneration is a common troglomorphic character of cave-dwelling organisms. Comparing the morphology and molecular biology of cave species and their close surface relatives is a powerful tool for studying regressive eye evolution and other adaptive phenotypes. We compared two co-occurring and closely-related species of the fish genus Sinocyclocheilus, which is endemic to China and includes both surface- and cave-dwelling species. Sinocyclocheilus tileihornes, a cave species, had smaller eyes than Sinocyclocheilus angustiporus, a surface species. Histological and immunohistochemical analyses revealed that the cave- fish had shorter cones and more disorderly rods than did the surface-dwelling species. Using quantitative PCR and in situ hybri- dization, we found that rhodopsin and a long-wavelength sensitive opsin had significantly lower expression levels in the cavefish. Furthermore, one of two short-wavelength-sensitive opsins was expressed at significantly higher levels in the cavefish. Changes in the expression ofopsin genes may have played a role in the degeneration of cavefish eyes [Current Zoology 59 （2）： 170-174, 2013].

Field body temperature and thermal preference of the big-headed turtle Platysternon megacephalum

The big-headed turtle Platysternon megacephalum is a stream-dwelling species whose ecology is poorly known. We carried out field and laboratory investigations to determine field body temperatures and thermal preference of this species. In the field, the body temperatures of the turtles conformed to the water temperature, with little diel variation in either summer or au- tumn. Over the diel cycle, the mean body temperatures ranged from 20.8℃ to 22.2℃ in summer and from 19.3℃ to 21.2℃ in autumn; the highest body temperatures ranged from 22.1℃ to 25.0℃ in summer and from 20.6℃ to 23.8℃ in autumn. In the laboratory, the preferred body temperature （Tp） was 25.3℃ Food intake was maximized at 24.0℃, whereas locomotor perfor- mance peaked at 30.0℃. Consequently, Tp was closer to the thermal optimum for food intake than for locomotion. Therefore, this freshwater turtle has relative low field body temperatures corresponding to its thermal environment. In addition, the turtle prefers low temperatures and has a low optimal temperature for food intake [Current Zoology 59 （5）： 626-632, 20＇13].

EXPONENTIAL FOURIER COLLOCATION METHODS FOR SOLVING FIRST-ORDER DIFFERENTIAL EQUATIONS

In this paper, a novel class of exponential Fourier collocation methods （EFCMs） is presented for solving systems of first-order ordinary differential equations. These so-called exponential Fourier collocation methods are based on the variation-of-constants formula, incorporating a local Fourier expansion of the underlying problem with collocation meth- ods. We discuss in detail the connections of EFCMs with trigonometric Fourier colloca- tion methods （TFCMs）, the well-known Hamiltonian Boundary Value Methods （HBVMs）, Gauss methods and Radau IIA methods. It turns out that the novel EFCMs are an es- sential extension of these existing methods. We also analyse the accuracy in preserving the quadratic invariants and the Hamiltonian energy when the underlying system is a Hamiltonian system. Other properties of EFCMs including the order of approximations and the convergence of fixed-point iterations are investigated as well. The analysis given in this paper proves further that EFCMs can achieve arbitrarily high order in a routine manner which allows us to construct higher-order methods for solving systems of first- order ordinary differential equations conveniently. We also derive a practical fourth-order EFCM denoted by EFCM（2,2） as an illustrative example. The numerical experiments using EFCM（2,2） are implemented in comparison with an existing fourth-order HBVM, an energy-preserving collocation method and a fourth-order exponential integrator in the literature. The numerical results demonstrate the remarkable efficiency and robustness of the novel EFCM（2,2）.

The role of inflammation in epileptogenesis

Epilepsy is a chronic neurological disorder that has an extensive impact on a patient’s life.Accumulating evidence has suggested that inflammation participates in the progression of spontaneous and recurrent seizures.Proconvulsant incidences can stimulate immune cells,augment the release of pro-inflammatory cytokines,elicit neuronal excitation as well as blood-brain barrier(BBB)dysfunction,and finally trigger the generation or recurrence of seizures.Understanding the pathogenic roles of inflammatory mediators,including inflammatory cytokines,cells,and BBB,in epileptogenesis will be beneficial for the treatment of epilepsy.In this systematic review,we performed a literature search on the PubMed database using the following keywords:“epilepsy”or“seizures”or“epileptogenesis”,and“immunity”or“inflammation”or“neuroinflammation”or“damage-associated molecular patterns”or“cytokines”or“chemokines”or“adhesion molecules”or“microglia”or“astrocyte”or“blood-brain barrier”.We summarized the classic inflammatory mediators and their pathogenic effects in the pathogenesis of epilepsy,based on the most recent findings from both human and animal model studies.

ASYMPTOTIC BEHAVIOR OF HIGHER ORDER NONLINEAR INTEGRO-DIFFERENTIAL EQUATIONS WITH DEVIATING ARGUMENTS

In this paper, we study a class of higher order nonlinear integro-diferential equations with deviating arguments. With the aid of the integral inequality, we obtain some sufcient conditions under which all solutions to the equation have some asymptotic behavior.

Phylogenetic analysis and expression differences of eye-related genes in cavefish genus Sinocyclocheilus

The adaptive evolution of visual systems has been observed in many cavefish.However,little is known about the molecular mechanisms underlying these adaptations,which include regressive changes such as eye degeneration.Here,we analyzed phylogenetic and expression patterns of 6 eye-related genes(crx,foxg1b,opn1sw2,otx2,rho and sox2)in 12 Sinocyclocheilus species from China,including 8 stygobionts and 4 stygophiles,and examined photoreceptor cell morphology of these species.Those eye-degenerated species of Sinocyclocheilus were polyphyletic and showed different degrees of photoreceptor defects in responses to cave environments.The eye loss and degeneration are the result of convergent evolution.Although S.anophthalmus grouped with the eye-normal species,it displayed not only a high degree of eye degeneration but also significant expression differences in eyerelated genes compared with the eye-normal species.The gene foxg1b,which was determined to be under positive selection,might play an important role in the process of eye degeneration in S.anophthalmus based on differential expression.Eye-related gene expression and selection may have contributed to the polyphyly of the cave species.We examined gene expression and duplication in 6 eye-related genes and revealed that these genes displayed considerable diversity in relative expression in Sinocyclocheilus fishes.Otx2 and sox2 were significantly up-regulated in individual cave species,while the other 4 genes(crx,foxg1b,opn1sw2 and rho)were significantly down-regulated.These findings provide a valuable resource for elucidating molecular mechanisms associated with visual system evolution in cavefish.

ON THE BOUNDEDNESS OF A CLASS OF NONLINEAR DYNAMIC EQUATIONS OF THE THIRD ORDER

In this paper, a modified nonlinear dynamic inequality on time scales is used to study the boundedness of a class of nonlinear third-order dynamic equations on time scales. These theorems contain as special cases results for dynamic differential equations, difference equations and q-difference equations.

OSCILLATION CRITERIA FOR SECOND ORDER FUNCTIONAL NEUTRAL DIFFERENTIAL EQUATIONS

By the standard integral averaging technique, we obtain some oscillation criteria for a second order functional neutral differential equation. Our results are more general than those in B. Baculíková, J. Dzurina [2]. An example is provided to illustrate the relevance of our theorems.

STABILITY AND BOUNDEDNESS OF SOLUTIONS FOR A CERTAIN FOURTH-ORDER DELAY DIFFERENTIAL EQUATION

In this paper, with the help of Lyapunov functional approach, sufficient conditions for the asymptotic stability of zero solution for a certain fourthorder non-linear delay differential equation are given.