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The development and biological characteristics of Haemaphysalis longicornis were investigated under field conditions in Xiaowutai National Natural Reserve Area, North China. Unfed larvae, nymphs and adults were fed on rabbits and exposed to daylight. Three free-living stages were allowed to develop in field plot selected in a tick natural habitat. The host seeking behavior and seasonal occurrence were observed. Haemaphysalis longicornis were active from mid March to mid October. The premoult period of nymphs and preoviposition of females were regulating phases of their life cycle. The developmental durations of eggs, larvae and adults were constant under field conditions regardless when the development started. The oviposition periods in May and June were statistically shorter than those in July and August. The daily oviposition patterns of females engorged in May and June demonstrated unobvious peak, which differed from those engorged in July and August. The daily oviposition peak of the latter occurred on the 4th day of oviposition. Moreover, a positive correlation was found between the mass of the laid egg and the body weight of engorged females (r = 0.62, P < 0.001). The female reproductive efficiency indices were 2.9, 6.1, 10.5 and 9.0 in May, June, July and August, respectively. The mean weight (3.33 mg) of engorged nymphs molting to females was significantly higher than that (2.35 mg) of those molting to males (P < 0.001), but the body weights of both sexes were overlapping.

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A theoretical hierachy of human relationships is constructed in terms of altruism. It is hypothesized that the probability for an actor A to perform an altruistic act to a person B depends on the relationship between A and B, and the probability decreases consistently in the following order of relationships: close relatives, best friends, strangers who are very weak or very young or who are elite in society, common strangers, and enemies. Two hypothetical moral dilemmas were used to study the hierarchy and five test scores expressing correspondingly the above human relationships were constructed. The sample consisted of 400 English subjects in London and 519 Chinese subjects in Hong Kong. It was found that (i) the intercorrelations of the five score variables displayed a simplex-like structure and (ii) loadings for the score variables approximated a two-factor, semicircular configuration with score variables ordered by their hierarchical positions. The findings in both the London and Hong Kong Studies supported the proposed hierarchical structure of human relationships.

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The objective of this paper is to measure the effect of an axial magnetic field (AMF) BAMF and arc current on the anode current density in diffuse vacuum arcs. The experimental geometry included a split anode and a butt-type cathode, both with a diameter of 60 mm. The anode surface was divided into a central area and three symmetrically disposed peripheral annular areas. The central area of the split anode had a diameter of 20 mm. The contact material was CuCr25 (25% Cr). The arc current IARC ranged from 4 to 14 kA (rms) at 50 Hz. The opening velocity was 2.4 m/s. The currents of the four areas on the anode contact were measured using four Rogowski coils situated outside the vacuum chamber. An external uniform AMF BAMF ranging from 0 to 110 mT was applied during the experiment. The observed arc modes were recorded by a high-speed charge-coupled device video camera. The experimental results quantitatively reveal that the current density distribution on the anode surface in the diffuse arc mode was not uniform but concentrated in the central area. The current density in the central anode area at the current peak JPeakArea I decreased with increasing BAMF following a power law. For BAMF of 0–110 mT and IARC of 4–14 kA, JPeakArea I = (2.2 IARC + 0.069 IARC2) BAMF−0.22, where JPeakArea I is in A/mm2, BAMF is in mT, and IARC is in kA. Moreover, the current distribution was uneven in the three peripheral areas.

every 5 tests and testing was performed at least 3 minutes after filling the cell. 20 such measurements were then processed using Weibull statistics. Electrical conductivity measurements were undertaken according to ASTM D1169 in a 5 ml concentric cylinder test cell with an electrode gap of 2 mm. A voltage was applied using a Spellman SL10 HVDC power supply and a Keithley 6487 Picoammeter was used to measure the resulting current. A step voltage program was employed; raise the voltage by 100 V, wait 10 s for any capacitive currents to dissipate and then record the current. III. RESULTS A. Electrical ageingElectrical ageing results in the formation of particulate matter and darkening of the oils as described previously [2, 3, 6]. Due to the increased sample volume used currently, increased ageing times were used to achieve similar levels of ageing to before [6]. The UV/Vis spectra of Fig. 2a show absorbance over all wavelengths, but viscosity measurements (Fig. 2b) did not indicate any significant (uncertainty ±0.001