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It is well known that mono-sex culture has the advantages of a more rapid growth rate, more uniform size and lower energy consumption of gonadal development in fish. In production practice, male mandarin fish (Siniperca chuatsi) show great aquaculture value after the overwintering stage. As a species with an XY-type sex determination system, feminizing genetically male fish into physiological female fish and breeding YY supermales is a common method used to produce all-male populations. In this study, we systematically investigated feminization of mandarin fish by indirect feeding of 17β-estradiol (E 2) at different doses (200, 400 and 600 mg/kg). Neo-females were successfully yielded in all E 2 -treated concentrations. The sex-reversed ratios of the 200, 400 and 600 mg/kg E 2 -treated groups were 40%, 87% and 100%, respectively. From 45 to 135 dat (days after treatment), the gonads in the 600 mg/kg E 2 -treated group consisted of oogonium and previtellogenic oocytes. At 165 dat, early vitellogenic oocytes were observed in the gonads of the 600 mg/kg E 2 -treated group. Regarding the expression of sex-related genes, 600 mg/kg E 2 -treated mandarin fish presented a different gene expression pattern from that of normal males. Moreover, the growth and development status were also analysed in XY normal males and YY supermales at 360 dph, and YY supermales showed a higher number of lumina and significantly lower growth performance than XY normal males. In conclusion, we have established a technique for efficiently inducing male to female sex reversion and YY supermale breeding of mandarin fish, which provides a great foundation for the production of all-male mandarin fish. • Neo-females were successfully yielded in all three concentrations of E 2 (200, 400 and 600 mg/kg). • YY super-male mandarin fish was also obtained, which showed stronger reproductive capacity and slow growth speed. • Our study lays a great foundation for the production of all-male mandarin fish. [ABSTRACT FROM AUTHOR]

Increasing concerns about traffic congestion, road safety, greenhouse gas emissions and energy consumption have resulted in people making different transportation choices, which in turn are affecting future mobility patterns. As "sustainable mobility" has become an increasingly popular idea, the focus of recent transportation research has been to identify and build a sustainable transport future. With this in mind, this paper developed an evolutionary trajectory for car sharing developments based on the technological paradigm to achieve sustainable mobility. A data analysis system (DAS) was built to identify the car sharing developments and literature mining and science mapping conducted to develop a new definition for the car sharing technological paradigm (CSTP). In each CSTP phase, some representative car sharing technologies or modes are discussed: single mode in the first competition stage; fusion mode in the second diffusion stage; and the integration of different modes in the third shift stage. Disruption was observed to occur when the first two stages went to the shift stage-integration mode and four disruptive technology-driven trends were identified in the paradigm shift from the existing paradigm to the new paradigm-sustainable mobility. The tech-integrated analyses found that the connected, autonomous, shared, electric (CASE) integration framework was a possible future sustainable mobility trend. The market dynamics analysis found that along with the key technologies, consumers, regulations and economic considerations, CASE was being implemented and deployed in the market. As it was found that policy has the opportunity to affect the future path to be taken, policy implications are outlined for future tech-integrated developments. The results of this study provide the government, the market, and the public, with information and guidance on the application of the proposed framework to ensure a sustainable mobility future. • Data-driven approaches system is developed towards visualization analysis and technological paradigm theory. • Car sharing technological paradigm (CSTP) is proposed as existing paradigm. • Disruptive technologies in the shift phase lead to a paradigm shift to a new paradigm-sustainable mobility. • The connected, autonomous, shared, electric (CASE) integration is a possible future sustainable mobility trend. • Policy has the opportunity to affect the future path to be taken. [ABSTRACT FROM AUTHOR]

In the face of climate change and possible future energy shortages, the installed capacity of clean energy natural gas (NG) and renewable energy (RE) for power generation has gradually increased. However, in the traditional electricity market, there is significant competition between NG and RE as gas prices tend to be volatile, and RE power generation from wind and solar can be intermittent and somewhat unreliable, indicating that these power sources have some drawbacks if used to independently generate electricity; therefore, determining the balance of NG and RE to ensure are resilient, reliable, flexible and affordable power generation system is an important goal. Based on the data analysis system (DAS) combined with paradigm theory, this paper examines the possibility of hybrid power generation in the future. The results of literature analysis visualization show that NG or RE has its own power generation paradigm, and a paradigm shift towards hybrid NG-RE power generation was found, so NG-RE power generation paradigm (NGREP) was proposed. To determine whether these NG-RE hybrid energy developments could be more competitive than separate developments, a comparative analysis was conducted, from which it was found that hybrid NG-RE systems are more attractive in some cases. However, as there are still challenges in the developments of these systems, a driving force is needed to promote further hybrid developments. Using hybrid power generation in areas with plentiful wind, solar and gas can maximize energy use efficiency and significantly reduce carbon emissions and other pollutants. [ABSTRACT FROM AUTHOR]

Proponents of distributive justice with regard to energy hold that every household has the right to affordable access to energy. However, when passively participating in clean energy reform policies, households, and especially low-income households, are often forced to use energy beyond the scope of affordability, resulting in distributive injustice. However, research on the quantitative estimation of injustice in energy distribution is still rare. In this paper, an evaluation model of energy vulnerability and distributive justice is established through the "reverse deduction method," and the change value of energy vulnerability before and after energy reform is used to calculate the loss value of distributive justice, which is used as the basis for energy policy evaluation. Taking the policy of replacing coal with natural gas for rural heating in Gaocheng District, Hebei Province, China as a case study, the value of lost distributive justice is calculated. The results show that 34.51% of households experienced distributive injustice after the energy reform, while 19.34% of households improved their energy vulnerability and achieved energy justice through energy subsidy policies. However, 46.15% of households were able to adapt to the energy reform independently without subsidies, which indicates a waste of resources in the energy subsidy policy. The policy implication of these results is that differentiated energy subsidy policies should be implemented according to household energy vulnerability, so as to maximize the policy benefits on the premise of ensuring justice in household energy distribution and minimizing injustice. The empirical study proves that the method of assessing injustice in energy distribution based on the "reverse deduction method" of energy vulnerability is feasible and a new attempt. • The passive participation of low-income households in clean energy reform policies results in distributive injustice. • Apply the vulnerability framework to calculate energy distribution injustice. • The implementation of differentiated subsidies can effectively improve the vulnerability of rural households energy poverty. • It is feasible and a new attempt to measure energy distributive injustice by using the "reverse deduction method". [ABSTRACT FROM AUTHOR]