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Although parthenogenesis is widespread in nature and known to have close relationships with bisexuality, the transitional mechanism is poorly understood. Artemia is an ideal model to address this issue because bisexuality and "contagious" obligate parthenogenesis independently exist in its congeneric members. In the present study, we first performed chromosome spreading and immunofluorescence to compare meiotic processes of Artemia adopting two distinct reproductive ways. The results showed that, unlike conventional meiosis in bisexual Artemia, meiosis II in parthenogenic Artemia is entirely absent and anaphase I is followed by a single mitosis-like equational division. Interspecific comparative transcriptomics showed that two central molecules in homologous recombination (HR), Dmc1 and Rad51, exhibited significantly higher expression in bisexual versus parthenogenetic Artemia. qRT-PCR indicated that the expression of both genes peaked at the early oogenesis and gradually decreased afterward. Knocking-down by RNAi of Dmc1 in unfertilized females of bisexual Artemia resulted in a severe deficiency of homologous chromosome pairing and produced univalents at the middle oogenesis stage, which was similar to that of parthenogenic Artemia, while in contrast, silencing Rad51 led to no significant chromosome morphological change. Our results indicated that Dmc1 is vital for HR in bisexual Artemia, and the deficiency of Dmc1 may be correlated with or even possibly one of core factors in the transition from bisexuality to parthenogenesis. [ABSTRACT FROM AUTHOR]

Vehicle exhaust emissions are identified as one of the main determinants of air pollution and play an important role in the environmental sustainable improvement of countries. This research utilizes a panel data of 30 Chinese provinces during the period between 1997 and 2012 to examine the existence of inverted U-shaped relationship between public healthcare expenditure per capita and private car ownership across geographical regions (east, middle and west China) employing panel generalized method of moments estimates for robust estimates. The findings also show the income per capita significantly and positively impacts on health expenditure per capita at the national level. The other results indicate that sulfur dioxide emissions and people over age 65 significantly increase healthcare expenditure per capita except the western region; soot emissions have a significantly positive impact on public health expenditure per capita for only the whole country and the western region; the number of doctors per capita may decrease public health expenditure per capita caused by environmental pollution. These results have important policy implications for promotion of new energy vehicles and for improving air quality and medical and health services. [ABSTRACT FROM AUTHOR]

Fossil energy consumption is one of the main reasons for the deterioration of environmental pollution and decline in public health. This paper tests for the long-run and short-run relationship among energy consumption, environment pollution and public health using the autoregressive-distributed lag approach in China for the period 1985-2014. The study used energy consumption variables (i.e., the proportion of coal consumption, that of oil and clean energy, abbreviated as PCC, POIL and PCE, respectively), environmental pollution ones (i.e., SO emissions, abbreviated SO, soot and dust emissions,), two health proxies (i.e., the proportion of cardiovascular and respiratory diseases mortality, abbreviated as PCD and PRD, respectively). These variables were selected due to vital importance in China. The overall results indicate that there was co-integration relationship under the study with statistically significantly positive relationship between environmental pollution and energy consumption, public health and environmental pollution in the short and long run. Comparing the long-run and short-run coefficients of energy use variable with respect to SO and soot indicates that the long-run coefficients are the same as the short-run. The long-run coefficients of soot and dust emissions with respect to PCD and PRD, respectively, are higher than the short-run coefficients. This implies that environment pollution level is found to worsen with respect to fossil energy use presently and over time, while public health level descending with reference to soot and dust emission over time in China. The Granger causality results suggested a unidirectional Granger causality between energy use and environment pollution, environment pollution and public health. The results emphasized the importance of energy transformation and sustainable development policies that help to adjust the structure of energy consumption and to improve public health level. [ABSTRACT FROM AUTHOR]

The effects of the composition of plasma gases (Ar-N2, Ar-H2), arc current, and voltage on the temperature and velocity of a low-power (5 kW) plasma torch in the arc field free region has been investigated using an enthalpy probe. Coatings of Al2O3-13TiO2 were deposited under different conditions. The results show that in the Ar-N2 plasma, the enthalpy, temperature, and velocity change little with arc current and voltage when regulating the nitrogen proportion in the plasma gas. The hardness of the resulting coatings is 800 to 900 kg/mm2 HV.300. For Ar-H2 plasma, however, increases in the H2 content in the mixture of the gases remarkably enhanced the velocity and heat transfer ability of the plasma jet, with the result that the coatings showed high hardness up to 1200 HV. [ABSTRACT FROM AUTHOR]