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In temperate shallow lakes, submerged macrophytes facilitate zooplankton development by providing refuge against fish predation and, thereby, indirectly contribute to maintaining a clear-water state through enhanced zooplankton grazing. The role of macrophytes for zooplankton and their grazing potential is less clear for tropical lakes. We investigated crustacean zooplankton in a phytoplankton-dominated basin (algal basin) and two restored basins dominated by macrophytes (macrophyte basins) in the shallow Huizhou West Lake in tropical southern China. We found that copepods prevailed in all basins, but the dominant taxon differed, with omnivorous cyclopoids dominating in the algal basin and herbivorous calanoids in the macrophyte basins. Moreover, the biomass ratios of calanoid:copepod and zooplankton:phytoplankton were higher in the macrophyte basins than in the algal basin. Our results suggest that restoration measures involving macrophyte transplantation and fish removal lead to reduced fish predation on zooplankton, which help to maintain the clear-water state when macrophytes are established due to higher control on phytoplankton. However, unlike in temperate lakes, large-bodied Daphnia were generally absent and the zooplankton:phytoplankton ratio was overall low, indicating a weaker top-down control in tropical lakes, which is likely due to higher fish predation. [ABSTRACT FROM AUTHOR]

Background: Thalassemia is one of the most common monogenetic diseases in the south of China and Southeast Asia. Hemoglobin Bart's hydrops fetalis syndrome was caused by a homozygous Southeast Asian deletion (-/-) in the HBA gene. Few studies have proved the potential of screen for Bart's hydrops fetalis using fetal cell-free DNA. However, the number of cases is still relatively small. Clinical trials of large samples would be needed.Objective: In this study, we aimed to develop a noninvasive method of target-captured sequencing and genotyping by the Bayesian method using cell-free fetal DNA to identify the fetal genotype in pregnant women who are at risk of having hemoglobin Bart hydrops fetalis in a large-scale study.Study Design: In total, 192,173 couples from 30 hospitals were enrolled in our study and 878 couples were recruited, among whom both the pregnant women and their husbands were detected to be carriers of Southeast Asian type (-/αα) of α-thalassemia. Prenatal diagnosis was performed by chorionic villus sampling, amniocentesis, or cordocentesis using gap-polymerase chain reaction considered as the golden standard.Results: As a result, we found that the sensitivity and specificity of our noninvasive method were 98.81% and 94.72%, respectively, in the training set as well as 100% and 99.31%, respectively, in the testing set. Moreover, our method could identify all of 885 maternal samples with the Southeast Asian carrier and 36 trisomy samples with 100% of sensitivity in T13, T18, and T21 and 99.89% (1 of 917) and 99.88% (1 of 888) of specificity in T18 and T21, respectively.Conclusion: Our method opens the possibility of early screening for maternal genotyping of α-thalassemia, fetal aneuploidies in chromosomes 13/18/21, and hemoglobin Bart hydrops fetalis detection in 1 tube of maternal plasma. [ABSTRACT FROM AUTHOR]

Abstract: The magnitude, temporal, and spatial patterns of greenhouse gas (hereafter referred to as GHG) fluxes from soils of plantation in the subtropical area of China are still highly uncertain. To contribute towards an improvement of actual estimates, soil CO2, CH4, and N2O fluxes were measured in two different land-use types in a hilly area of South China. This study showed 2 years continuous measurements (twice a week) of GHG fluxes from soils of a pine plantation and a longan orchard system. Impacts of environmental drivers (soil temperature and soil moisture), litter exclusion and land-use (vegetation versus orchard) were presented. Our results suggested that the plantation and orchard soils were weak sinks of atmospheric CH4 and significant sources of atmospheric CO2 and N2O. Annual mean GHG fluxes from soils of plantation and orchard were: CO2 fluxes of 4.70 and 14.72MgCO2–Cha−1 year−1, CH4 fluxes of −2.57 and −2.61kgCH4–Cha−1 year−1, N2O fluxes of 3.03 and 8.64kgN2O–Nha−1 year−1, respectively. Land use types had great impact on CO2 and N2O emissions. Annual average CO2 and N2O emissions were higher in the orchard than in the plantation, while there were no clear differences in CH4 emissions between two sites. Our results suggest that afforestation could be a potential mitigation strategy to reduce GHG emissions from agricultural soils if the observed results were representative at the regional scale. CO2 and N2O emissions were mainly affected by soil temperature and soil moisture. CH4 uptakes showed significant correlation with soil moisture. The seasonal changes in soil CO2 and N2O fluxes followed the seasonal weather pattern, with high CO2 and N2O emission rates in the rainy period and low rates in the dry period. In contrast, seasonal patterns of CH4 fluxes were not clear. Removal of surface litter reduced soil CO2 effluxes by 17–25% and N2O effluxes by 34–31% in the plantation and orchard in the second sampling year but not in the first sampling year which suggested micro-environmental heterogeneity in soils. Removal of surface litter had no significant effect on CH4 absorption rates in both years. This suggests that microbial CH4 uptake was mainly related to the mineral soil rather than in the surface litter layer. [Copyright &y& Elsevier]

Objective: To explore the association between the arylhydrocarbon receptor gene (AhR) 1661G/A or arylhydrocarbon nuclear translocatorgene (ARNT) 567G/C polymorphism and endometriosis in southern Han Chinese women., Methods: The polymorphisms of AhR gene 1661G/Aand ARNT gene 567G/C in 431 cases of endometriosis and 499 healthy women were genotyped by fluorescence quantitative PCR-based high resolution melting., Results: The frequencies of genotypes AA, AG, GG and alleles A and G in controls were 12.0%, 41.9%, 46.1%, 33.0% and 67.0%, respectively, which were not significantly different from those in patients with endometriosis (9.7%, 44.6%, 45.7%, 32.0% and 68.0%, respectively). The genotype frequencies of GG, GC, CC and alleles C and G in controls (15.6 %, 51.7%, 32.7%, 58.5%, 41.5%) were not significantly different from those in patients with endometriosis (13.5%, 47.8%, 38.7%, 62.6%, 37.4%), either. And no interaction of AhR 1661G/A and ARNT 567G/C on endometriosis was found., Conclusion: No association between AhR 1661G/A and ARNT 567G/C genetic polymorphisms and endometriosis was found in the southern Han Chinese women in this study.

Different parts of twenty dominant plant species in five plantation communities on the subtropical hilly lands in Heshan of Gunagdong as well as the litters from three of the five plantation communities were sampled, and their gross caloric value (GCV) and ash content were measured by using a PARR-1281 oxygen bomb calorimeter and a muffle furnace. Based on the measurements, the ash-free caloric value (AFCV) of the samples was calculated, and the characteristics of caloric value and ash content of the samples, according to plant part, individual, and plant growth form, were analyzed. The results showed that the GCV and AFCV of leaf, branch, stem wood, stem bark, and root were in the range of 10.7-22.17 kJ x g(-1) and 13.89-23.04 kJ x g(-1), respectively. The GCV and AFCV of leaf were significantly higher than those of other parts (P < 0.05), and the individual plant' s weighted mean values of GCV and AFCV were in the range of 14.24-19.43 and 16.63-20.99 kJ x g(-1), respectively. The mean AFCV of plantation communities was in the order of tree layer (19.55 kJ x g(-1)) > shrub layer (19.46 kJ x g(-1) > herb layer (18.77 kJ x g(-1)), with indigenous coniferous tree (19.86 kJ x g(-1)) > indigenous broad-leaved tree (19.55 kJ x g(-1)) > exotic eucalyptus (19.18 kJ x g(-1)), while the mean ash content was just the opposite. In Acacia mangium, coniferous, and Schima plantation communities, the GCV and AFCV of litters were higher than those of various plant parts (P < 0.01). The litter-falls in A. mangium and coniferous plantations had higher mean GCV and AFCV than the litters and fresh leaves of tree layer, while the fresh leaves of tree layer in Schima plantation showed higher mean GCV and AFCV.