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Abstract: Although the importance of material wealth to population growth is the core of Malthusian theory about population dynamics in pre-transitional societies, our understanding of the relationship between wealth and reproductive success in China is still limited. Until recently, there was little in the way of relevant data. In the absence of empirical evidence to the contrary, conceptions of the Chinese demographic regime were largely Malthusian, in that they did not account for the possible role of a fertility-based preventive check. In this study, we examine wealth differentials in reproduction in historical rural China by using newly available longitudinal individual level demographic and household level land holding data for 108,100 immigrants and their descendants living in 120 villages in Shuangcheng, Northeast China, between 1866 and 1907. Our study demonstrates a positive correlation between land holding status and marital fertility among the population under study. In addition, there is also a clear pattern of fertility differentials according to household context and other measures of socioeconomic status. Our findings suggest that these fertility differentials are not only results of certain social institutions and customs but also the consequences of couple''s behavior of fertility control in response to socioeconomic and other household conditions. [Copyright &y& Elsevier]

Fast development of farming practices in China is projected to result in additional carbon emissions and thus affect farmland ecosystems' environmental performance. Based on 454 farm surveys on the North and Northeast China Plain, the carbon footprint (CF) of two farmland ecosystems (irrigated system for wheat and maize on the North China Plain and rainfed system for maize on the Northeast Plain) were assessed and emission reduction pathways explored by quantifying greenhouse gas emissions of agricultural inputs and farm practices during the entire crop growing seasons with an agricultural footprint model. The results demonstrated that the GHG emissions from wheat and maize rotation in the irrigated system were 7.63 t CO 2 eq ha−1 and 3.17 t CO 2 eq ha−1 for single season maize in the rainfed system. While energy consumption accounted for 12.5%–21.3% of the carbon footprint in both systems, the group assessment found that the largest difference in GHG emissions between the high and low emission groups came from mechanical energy consumption. Approximately 50.6% and 39.2% of the mechanical carbon footprint of wheat and maize, respectively, were caused by irrigation practices in the irrigated system. Regarding the rainfed system, where 46.6% of mechanical carbon emissions were generated by maize tillage operations. In addition, scenario analysis indicated that the mechanical carbon footprint could be reduced to 56 kg CO 2 eq t−1 for NCP-wheat and 26 kg CO 2 eq t−1 for NCP-maize, respectively, by optimizing yields and irrigation practices in irrigated systems and that the mechanical carbon footprint of NEP-maize could be reduced to 25 kg CO 2 eq t−1 by optimizing yields and tillage practices in rainfed systems. Therefore, improvement in mechanization in irrigation and tillage practices can contribute to reduce GHG emissions in China. Water-saving irrigation technology is recommended in irrigated area and conservation tillage is recommended in rainfed agricultural area to reduce carbon footprints. [Display omitted] • Carbon footprint of farming practices was studied on the North and Northeast China Plains. • Irrigation practice affects the carbon footprint of the winter wheat–summer maize system. • Tillage practice determines the carbon footprint of the rain-fed spring maize system. • Promoting drip irrigation in irrigated system and strip-tillage in rainfed system could reduce the carbon intensity. [ABSTRACT FROM AUTHOR]

Purpose: To explore the prevalence and clinical features, especially the reproductive function, of 45,X mosaicism patients in northeast China. Methods: GTG-banding was performed on a series of 2,250 patients from our genetic counseling clinic. Each of these patients underwent a physical examination and was interviewed about their medical history and reproductive problems. Literature on 45,X mosaicism was accessed using PubMed and reviewed. Results: The prevalence of 45,X mosaicism in northeast China is 0.36 % (8/2250), and the mosaic karyotype of our study accounted for 61.54 % (8/13) of Turner syndrome cases. This is comparable with studies from Asia, Europe, South America and other regions. The affected patients showed genital abnormalities, abnormal pregnancy or infertility. Conclusion: 45,X mosaicism is commonly seen in the genetic counseling clinic. Extensive cytogenetic assessment may improve the detection rate in patients with congenital dysplasia, or history of abnormal pregnancy or infertility. Karyotyping plays a key role in prognosis and assisted reproduction or early surgical treatment. [ABSTRACT FROM AUTHOR]