Search

Whereas there is a large literature evaluating the impacts of education, most of the focus has been on getting to universal primary enrollment and understanding the returns to basic education; but it misses the major shifts toward higher education in many fast-growing parts of the developing world over the last 20 years. In this paper, I study the returns to higher education in China using the reinstatement of the National College Entrance Examination in 1977 as a natural experiment, investigating the causal impacts of higher education on later life outcomes and well-being. Through a combination of regression discontinuity and difference-in-difference methods, I find that cohorts that were more likely to complete high school and obtain a college education as a result of the reform were no more likely to be employed, but were more likely to have a high-socioeconomic (SES) occupation in their early 30s, and lesser of the same in their 40s. Cohorts with higher education work for fewer days in a week, and, on average, earn a higher monthly income by 56 percent in their late 40s. [ABSTRACT FROM AUTHOR]

• Human metapneumovirus (HMPV) is an important respiratory pathogen that causes acute respiratory tract infection in children ≤5 years old. • The prevalence peak of HMPV in southern China appeared between March and May. • Respiratory syncytial virus is the most common respiratory virus coinfected with HMPV in children. • The predominant subtype of HMPV in this area is B1, followed by A2c subtype. • Long sunshine duration might decrease the HMPV prevalence. This study aimed to determine the epidemiological and genetic features of human metapneumovirus (HMPV) infection in children in southern China, and the effect of meteorological factors on infection. 14,817 children (≤14 years) with acute respiratory tract infections from 2010 to 2019 were examined for HMPV and other respiratory viruses by real-time quantitative polymerase chain reaction. Full-length F gene of 54 positive samples were sequenced and subjected to phylogenetic analysis. The correlation between the HMPV-positive rate and meteorological factors was analyzed by linear regression analysis. HMPV was detected in 524 (3.5%) children, who were mostly younger than 1 year. The seasonal peak of HMPV prevalence mainly occurred in spring. Respiratory syncytial virus was the most common virus coinfected with HMPV (5.3%). Phylogenetic analysis revealed that the sequenced HMPV strains belonged to four sublineages, including A2b (1.9%), A2c (31.5%), B1 (50.0%), and B2 (16.7%). After adjusting for all meteorological factors, sunshine duration was inversely correlated with the HMPV-positive rate. HMPV is an important respiratory pathogen that causes acute respiratory tract infections in children in southern China, particularly in children ≤5 years old. The prevalence peak of HMPV in this area appeared in spring, and the predominant subtype was B1. Meteorological factors, especially long sunshine duration, might decrease the HMPV prevalence. [ABSTRACT FROM AUTHOR]

• ∼785 Ma mafic-ultramafic cumulates in West Cathaysia formed from hydrous basaltic magmas. • Their geochemical data are consistent with arc-related cumulate petrogenesis. • They were probably formed at a crustal depth in a subduction setting. • Yangtze and West Cathaysia were not amalgamated in the Tonian, but more likely in the early Paleozoic. The Neoproterozoic tectonic setting of the West Cathaysia terrane and its relationship with the Yangtze Block are critical to understanding the formation and tectonic evolution of South China. A detailed study of late Tonian mafic-ultramafic cumulate slivers embedded in the Shenshan tectonic mélange along the northwest margin of West Cathaysia is presented here with the aim of elucidating its Neoproterozoic tectonic history. These partly-altered mafic-ultramafic rocks include olivine-bearing cumulates (olivine pyroxene hornblendite or olivine hornblende pyroxenite), pyroxene hornblendite, and gabbroic cumulates. The early crystallization of clinopyroxene and the abundance of hornblende indicate that they formed from hydrous magmas. The rocks have similar geochemical distribution patterns and show variable initial 87Sr/86Sr ratios of 0.702679 to 0.709742 and positive εNd(t) values of +2.10 to +4.52. The mineral compositions of the clinopyroxene and hornblende and their whole-rock extended normalized trace element patterns show features (e.g., negative Nb anomalies, LILE enrichment) typical of rocks with an arc affinity. The high calculated Mg# values (58–77, average 71) of the equilibrium magmas are close to those of primary mantle-derived basalts. We conclude that these mafic and ultramafic cumulates were derived from a subduction-related, hydrous, magnesian basalt in a subduction setting. The estimated crystallization temperature and pressure, based on the composition of the amphiboles, suggest that the minerals accumulated in magma chambers at middle to lower crustal depths. LA-ICP-MS U-Pb dating of zircon from the gabbroic cumulate indicates crystallization at ca. 785 Ma. A previous interpretation for West Cathaysia at this time involved a continental rift basin (the Nanhua basin) that straddled the southeastern margin of the Yangtze Block and the northwestern margin of West Cathaysia. In contrast, our results suggest that West Cathaysia was an arc at ca. 785 Ma, which supports the interpretation that the amalgamation between Yangtze and West Cathaysia did not occur in the Tonian, but more likely in the early Paleozoic. [ABSTRACT FROM AUTHOR]

The estuarine oyster (Crassostrea ariakensis), a species native to Asia, is widespread throughout the estuarine region along the northern and southern coasts of China and has important ecological and economic values. Owing to runoff dropping and environmental threats caused by climate change and anthropogenic influences, the natural resources of C. ariakensis have persistently declined. Therefore, breeding oysters with high adaptability, which requires efficient and accurate genotyping tools, is beneficial to restore the germplasm resources and aquaculture. However, targeted genotyping tools are poorly developed for this species and even in other aquatic species. Previously, we have detected some selective regions and genes associated with temperature and salinity adaptation using selection signature analysis and found that the upstream regulatory regions of the environment-responsive genes exhibited higher differentiation. In this study, we developed a single nucleotide polymorphism (SNP) targeted genotyping tool for C. ariakensis , which includes 30 K SNPs located in previously identified target regions. The target genomic regions were enriched by hybridization capture using double-stranded DNA (dsDNA) biotin-labeled probes, and sequenced with high depth. A total of 24,541 (81.8%) high-quality SNPs were successfully genotyped in 655 samples. Compared to the genotypes obtained from previous genome-wide resequencing, 74.2% of the SNPs had a consistency rate of 1, with an average consistency rate for each sample of 97.8%. Population structure analysis showed three divergent populations (northern, southern, and middle) on the coast of China, consistent with those constructed using SNPs derived from whole-genome resequencing data. Most of the 30 K SNPs were located in the intergenic and regulatory regions, whereas 7% were located in the coding region. These high-quality SNPs were located in 953 genes, including 100 heat-response and 348 high-salinity-responsive genes. Therefore, this panel can be used to evaluate the adaptive divergence between populations, and causative SNPs related to temperature and salinity adaptation in the linkage and association analysis, providing robust support for the molecular breeding of estuarine oyster. To the best of our knowledge, this study proposes the first high-throughput SNP-targeted genotyping tool for studying the genetic basis of environmental adaptation in oyster, and providing insights into the development of targeted SNP genotyping tools for the adaptation study in other aquatic species under climate changes. • We developed a 30 K targeted genotyping tool for Crassostrea. Ariakensis. • 24,541 high-quality SNPs were successfully genotyped in 655 samples. • These high-quality SNPs were located in environment-responsive genes. • 74.2% of the SNPs had a consistency rate of 1 with resequencing. Population structure analysis showed three divergent populations on the coast of China • This study could be used to dissect the genetic basis of environmental adaptation. [ABSTRACT FROM AUTHOR]

The use of electric bicycles (EBs) for short- and medium-distance travel provides an opportunity to decarbonize the transport sector. Using life cycle assessment, this study evaluated and compared the environmental and economic performances of EBs powered by four different types of batteries in China. The results show that EBs powered by lead-acid batteries have the worst environmental performance, whereas those powered by lithium iron phosphate batteries have the best environmental performance. Motor production was found to have the highest potential for metal depletion and toxicity for humans and ecology, owing to the use of copper in its production. These environmental consequences can be mitigated by continuous promotion of circular economy. The use stage brings about the most environmental pressure related to energy use. Power cleaning will reduce most environmental indicators by 10–25%. EBs powered by lithium manganate batteries have been a mainstream technology, but the short lifetime and low economic value of recycling the battery may constrain their development. [Display omitted] • Environmental and economic performance of electric bicycles (EBs) are evaluated. • Lead-acid battery EBs have the worst performance but use the least metals. • Motor is the component with the greatest environmental impact due to copper use. • Promoting circular economy can reduce environmental impact related to metal use. • EBs powered lithium-ion batteries have higher total cost but lower cost per km. [ABSTRACT FROM AUTHOR]

Oysters are a keystone species in estuaries and intertidal zones and have important economic and ecological significance; however, worldwide, the dominant aquaculture oyster species suffers from mass mortality owing to anthropogenic impacts and rapid climate change. As a possible solution, inter/intraspecies hybridization is a feasible way to breed new germplasms with genetic improvement and high environmental adaptability. Suminoe oysters (Crassostrea ariakensis) are broadly distributed in the estuaries of China and have evolved strong genetic divergence between the northern and southern populations; therefore, they are ideal candidates to explore intraspecies heterosis and the associated molecular mechanisms. In this study, we performed reciprocal hybridization and examined fitness traits in oysters cultured in both northern and southern habitats. Reciprocal hybrids performed better than inbred populations in both environments, indicating heterosis in Suminoe oysters. Hybrids reared in maternal habitats showed faster growth, higher field survival, and greater aerobic metabolism than alternative hybrid oysters under the same conditions. The transcriptional analysis identified modules related to heterosis and maternal effect, while genes responsible for galactose metabolism, glycolysis/gluconeogenesis, and the tricarboxylic acid cycle were enriched and upregulated in hybrids, especially those in maternal environments. Our findings reveal that accelerated aerobic energy metabolism, which may result from mitonuclear coadaptation, underlies the molecular basis of heterosis and maternal effect in the hybridization of Suminoe oysters. Thus, we provide important insights for the aquaculture management of marine species, revealing that selecting appropriate environments (maternal habitats) is critical for heterosis in cross-breeding. • Hybrids from divergent oyster populations showed heterosis in growth and survival. • Hybrids in maternal habitat exhibited better performance indicating maternal effect. • Accelerated aerobic metabolism underlies heterosis and maternal effect in oyster. • Our findings propose better hybridization breeding of hybrids in maternal habitat. [ABSTRACT FROM AUTHOR]

• The AOP approach in land management marked its pioneering effort. • Multi-path presentation provided holistic land ecosystem protection. • AOP identification unveiled pivotal ecological mechanisms confirming hypotheses. • Tailored strategies for distinct AOP stages were devised. • GIS visualization ensured precise strategy implementation within the AOP. At the regional scale, the complexity of ecological deterioration limits effective decision-making and preventive measures. In this study, an adverse outcome pathway approach was developed and applied to land resource management and environmental decision-making in Daye, a traditional mining city in China. First, adverse outcome pathways for land degradation were hypothesized. Second, a weight of evidence approach was used based on the data strength and causal chain strength of each degradation pathway. Then, the technique for order preference by similarity to an ideal solution (TOPSIS) was used with entropy information and integrated with the geographic information system (GIS) to evaluate the credibility of each pathway. The most likely adverse outcome pathway and the spatial distribution for different sub-regions were obtained. The apparent spatial heterogeneity suggests that land degradation pathways are closely associated with economic production activities in each sub-region. This study is expected to facilitate the identification of key mechanisms underlying ecological degradation and to guide the management of land systems to ensure long-term functioning. [ABSTRACT FROM AUTHOR]

The process of marine ecosystem collapse during the Permian–Triassic mass extinction may have varied in different paleogeographic settings and the intensity of oxygen depletion changed with different water depths. It remains largely unknown about the detailed biotic community collapse and its relation to paleo-redox condition in the deep-water basin. At the Kejiao section in the Nanpanjiang Basin of South China, the continuous sedimentation sequences and complete fossil records from the Changhsingian of Permian to the lowest Triassic provide a unique opportunity to study the progressive biotic crisis associated with oxygen deficiency in a deep-water setting. Here, we document high-resolution records of both the biodiversity dataset of different taxa and the redox data from the Kejiao section to achieve a new understanding of ecosystem deterioration associated with changes of redox conditions. The redox evolution revealed by changes in pyrite framboid size and morphology shows a change trend from lower dysoxic to oxygenated, and then to dysoxic interrupted by oxygenated and anoxic conditions in the late Changhsingian, and ending with euxinic conditions in the earliest Triassic. 60 species in 41 genera from radiolarians, bivalves, brachiopods and cephalopods were identified in the section and their occurrences show two pulses of extinction. The first pulse corresponds to the reduction in species richness of planktonic radiolarians and nektonic cephalopods, and the second pulse is documented by the wipe out of benthic brachiopods and remnant nektonic cephalopods and the decline in the species richness of benthic bivalves. This indicates the collapse of plankton and most nekton communities is ahead of the counterpart of benthos in the deepwater setting, supporting what observed in other sections in South China. The plankton and nekton communities inhabited water columns and the benthic community dwelled in the bottom water. Thus, the stagewise collapse of communities might be contributed by the expansion/migration, in particular, the downward expansion of Oxygen Minimum Zone (OMZ) documented by the information from pyrite framboids and the sedimentation. • New records on the largely unknown deep-water palaeocommunity collapse near the PTB. • Radiolarian, bivalve, brachiopod and cephalopod species were examined at Kejiao. • The collapse of plankton and most nekton communities is ahead of that for benthos. • Changes in pyrite framboid sizes show a fluctuated, deficient oxygen condition. • The stagewise collapse of communities recalled the expansion of OMZ. [ABSTRACT FROM AUTHOR]

Atmospheric aerosol pollution, such as fine particulate matter (PM 2.5) and inhalable particulate matter (PM 10), is one of the most important environmental problems in China. To mitigate particulate air pollution, the Chinese government has been implementing a series of clean air actions. Here, we conducted a comprehensive analysis on surface air pollutants data obtained from the China air quality observation network using a random forest (RF) approach, to evaluate the impact of clean air actions on aerosol pollution from 2015 to 2022. Overall, the observed PM 2.5 and PM 10 showed evidently decreasing trends during 2015–2022 in each season, with the largest trends in winter. Based on the RF model analysis, we further quantified the seasonal-dependent trends in PM 2.5 and PM 10 concentrations driven by anthropogenic emissions over China, which were approximately −3.84 and −6.14, −2.82 and −4.71, −2.58 and −4.45, and −2.77 and −4.06 μg m−³ yr−1 for winter, spring, summer, and autumn, respectively. Furthermore, anthropogenic emissions were estimated to contribute 34.44 and 54.98, 24.10 and 37.22, 23.48 and 36.20, and 21.04 and 30.69 μg m−3 to declines in annual mean PM 2.5 and PM 10 concentrations during the eight years in megacity clusters of eastern China for winter, spring, summer, and autumn, respectively. These seasonal-dependent trend analyses reveal the largest reduction in ambient aerosol pollution due to anthropogenic emission abatements during cold season and further demonstrate substantial effectiveness of the clean air actions for improvement in particulate air quality in China. Correlation analysis on PM 2.5 with the major meteorological parameters and the RF model built-in feature importance suggested that a combination of high relative humidity, shallow boundary layer heights, and low wind speeds could promote wintertime aerosol pollution in short-time scales over northern China (e.g., the North China plain). • Machine learning quantified aerosol pollution trends in China during 2015–2022. • Trends in aerosol pollution in all seasons was driven by anthropogenic emissions. • The largest emission-driven improvement in particulate air quality was in winter. [ABSTRACT FROM AUTHOR]

In past studies, the health and ecological risks of PCBs are well established. The impact of low-dose PCBs on aquatic ecosystems for an extended period is a matter of concern in the current era. The application of fatty acids (FAs) as bioindicators of pollution in the freshwater food web is almost unavailable. This study investigated concentrations of 209 PCB congeners, stable isotope levels, and FAs composition in ten freshwater species of Dongtinghu Lake, China. Total PCB congeners (∑PCBs) concentrations were ranged from 4.17 to 38.35 ng/g lipid weight. A total of 84 PCB congeners were detected out of 209 target PCB congeners, particularly PCB101, 118, 138, 153, and 155 found in all samples. The concentrations of 24 PCB congeners increased with trophic levels, but PCB 155 concentrations were consistent throughout trophic levels. The toxic equivalents (TEQ) of dl-PCBs (mostly PCB 126 and 169) also increased with trophic levels Out of total 35 FAs, 21 FAs were significantly positively correlated with 43 PCB congeners. Among FAs, C16:0 was the most abundant and positively correlated with most PCB compounds. Positive correlations between FAs and PCBs indicated that FAs can be used as efficient bioindicators of PCBs pollution in the aquatic food web. [Display omitted] • Stable isotope, fatty acids and PCBs were analyzed in a freshwater lake food web. • A total of 84 PCB congeners were detected out of 209 target PCBs. • Fatty acids were significantly positively correlated with PCBs in the food web. [ABSTRACT FROM AUTHOR]