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Dipetalonema gracile is a common parasite in squirrel monkeys (Saimiri sciureus), which can cause malnutrition and progressive wasting of the host, and lead to death in the case of massive infection. This study aimed to identify a suspected D. gracile worm from a dead squirrel monkey by means of molecular biology, and to amplify its complete mitochondrial genome by polymerase chain reaction (PCR) and sequence analysis. The results identified the worm as D. gracile , and the full length of its complete mitochondrial genome was 13,584 bp, which contained 22 tRNA genes, 12 protein-coding genes, two rRNA genes, one AT-rich region and one small non-coding region. The nucleotide composition included A (16.89%), G (20.19%), T (56.22%) and C (6.70%), among which A + T = 73.11%. The 12 protein-coding genes used TTG and ATT as start codons, and TAG and TAA as stop codons. Among the 22 tRNA genes, only trn S1AGN and trn S2UCN exhibited the TΨC-loop structure, while the other 20 tRNAs showed the TV-loop structure. The rrn L (986 bp) and rrn S (685 bp) genes were single-stranded and conserved in secondary structure. This study has enriched the mitochondrial gene database of Dipetalonema and laid a scientific basis for further study on classification, and genetic and evolutionary relationships of Dipetalonema nematodes. [ABSTRACT FROM AUTHOR]

In the increasingly complex world, decision makers need assistance in making informed transportation planning decisions. This article describes the application of rough set (RS) and back propagation neural network (BPNN) in the development of a novel hybrid intelligent model for forecasting the railway passenger traffic demand. The model intends to exploit the respective advantages of both RS and BPNN methods, but to avoid their respective weak points. The basic idea is to think of RS as the pre-treatment unit for BPNN that can mine knowledge from historical data. To do so, RS was used in data pre-treatment and constructing the decision table, and obtaining the minimum rule set from the decision table reduced by discretizing continuous attributes through a hybrid hierarchical k-means clustering. Input such rule set to the BPNN, trained on a sample dataset to determine parameters by using the Levenberg—Marquardt algorithm and the golden section algorithm. A hybrid intelligent forecasting model based on RS and BPNN is thus constructed and applied to forecast railway passenger traffic demand with pre-treated forecasting data. In the experiment, the railway passenger traffic data in China from 1991 to 2008 are selected as learning samples and testing samples, and the effectiveness of this method is verified in comparison to the linear recursive method. [ABSTRACT FROM AUTHOR]

This paper summarizes the preliminary assessment results of plasma vertical instability, based on six highly elongated plasma equilibria in the Chinese Fusion Engineering Test Reactor (CFETR) presently under design in China, by considering the stabilization effect of vessel and blanket modules. The double-layer vacuum vessel is found to be too far away from the plasma to provide effective passive stabilization, in terms of reducing the vertical instability growth rate. The blanket modules (BMs) are found to provide good stabilization, thanks to the associated conducting structures, first wall, manifold and back-plates being much closer to the plasma. The CFETR BMs, with reference material conductivity, have a good capability of slowing down growth rate to a level below 12.6 s−1. On the other hand, the vessel + BMs penetration time of τ w = 1081.2 ms and the blanket-alone penetration time of τ b = 879 ms are both much longer than the most unstable growth time of τ g = 79.4 ms, resulting in a strong shielding of external magnetic fields. The effect of BMs conductivity on the mode growth rate and estimate of the penetration time of conducting structures are performed to allow better prediction of the vertical instability in CFETR. The BMs mid-plane stabilizing structures are found to have very weak impact on the mode growth rate and the field penetration, and thus can be removed from consideration. The substantial difference between τ w and τ g indicates that vertical control will be lost before external radial field penetrates into the plasma region and interacts with plasma. As an important conclusion, this study recommends a design of in-vessel coils, powered by fast power supplies for controlling the vertical instability in CFETR. [ABSTRACT FROM AUTHOR]

• Assessment of open-loop growth rate for typical equilibria in HL-2 M is implemented. • We design an out-vessel active control system for vertical instability control. • Efficiency of each PF coil location for VDE control is investigated. • Control performance and power supply upgrade requirements are evaluated. • Further optimization of active control for advanced divertor plasma is done. Plasma vertical instability control is achieved by passive stabilization from induced currents flowing in surrounding structures and by active control using magnetic coils. Both aspects are numerically investigated for the medium-size copper tokamak HL-2 M, presently under construction in China. The double-shell vessel can provide some passive stabilization, with the longest wall penetration time of about 4 ms. We design an out-vessel active control system based on a single null divertor equilibria most demanding for vertical control and the maximum controllable vertical displacement dZmax ≥3.0 cm is required. Robust active control of the vertical instability can be achieved in HL-2 M, by the PF7U and PF7L coils connected in anti-phase and powered by an upgraded power supply with I max = 4.0 kA, V max =2 kV and f = 5 kHz. Safe control is possible for representative plasma configurations with growth rate ranging from 200 s−1 to 400 s−1. Efficiency of each PF coil location for VDE control is investigated, PF7U/L is most capable for single null and double null equilibria, but control capability of PF7U/L is not as good as PF2U/L for snowflake divertor plasma, PF7U/L and PF2U/L will be combined together to provide safe control of low βp 'close nulls' advanced divertor plasma in the future. [ABSTRACT FROM AUTHOR]