Limiting climatic factors in shaping the distribution pattern and niche differentiation of Prunus dielsiana in subtropical China

Subtropical forest in China has received much attention due to its complex geologic environment and bioclimatic heterogeneity.There have been very few studies addressing which climatic factors have shaped both distribution patterns and niche differentiation of species from this region.It also remains unclear whether phylogenetic niche conservatism retains in plant species from this biodiversityrich subtropical region in China.In this study,we used geographic occurrence records and bioclimatic factors of Prunus dielsiana(Rosaceae),a wild cherry species,combined with the classical ENM-based DIVA-GIS software to access contemporary distribution and richness patterns of its natural populations.The current distribution of P.dielsiana occupied a relatively wide range but exhibited an uneven pattern eastward in general,and the core distribution zone of its populations are projected to concentrate in the Wushan and Wuling Mountain ranges of western China.Hydrothermic variables,particularly the Temperature Seasonality(bio4)are screened out quantitatively to be the most influential factors that have shaped the current geographical patterns of P.dielsiana.By comparison with other sympatric families,climatic niche at regional scale showed a pattern of phylogenetic niche conservatism within cherry species of Ros aceae.The effect of habitat filtering from altitude is more significant than those of longitude and latitude.We conclude that habitat filtering dominated by limiting hydrothermic factors is the primary driving process of the diversity pattern of P.dielsiana in subtropical China.

LES of the Sandia flame series D-F using the Eulerian stochastic field method coupled with tabulated chemistry

In this paper,the Eulerian Stochastic Field(ESF)model in the Transported Probability Density Function(TPDF)class model is combined with the Flamelet Generated Manifolds(FGM)model.This method solves the joint probability density function transport equation by ESF method that considers the interaction mechanism between flame and turbulence with high precision.At the same time,by making use of the advantage of the FGM model,this model is able to incorporate the detailed chemical reaction mechanism(GRI 3.0)with acceptable computational cost.The new model has been implemented in the open source CFD suite-Open FOAM.Validation of the model has been carried out by simulating the Sandia flame series(three turbulent piloted methane jet flames)issued by the National Laboratory of the United States.The accuracy and advancement of the ESF/FGM turbulent combustion model are verified by comparing the LES results of the new model with the rich experimental data as well as the RANS results.The results demonstrate that the model has a strong ability in capturing combustion phenomena such as extinction and re-ignition in turbulent flame,which is essential in the accurate prediction of the combustion process in real combustion devices,for example,aircraft engines.

4-Mercaptopyridine Modified Fiber Optic Plasmonic Sensor for Sub-nM Mercury(II)Detection

In this paper,we propose and demonstrate a high-performance mercury ion sensor with sub-nM detection limit,high selectivity,and strong practicability based on the small molecule of the 4-mercaptopyridine(4-MPY)modified tilted fiber Bragg grating surface plasmon resonance(TFBG-SPR)sensing platform.The TFBG-SPR sensor has a rich mode field distribution and a narrow bandw idth,which can detect the microscopic physical and chemical reactions on the sensor surface with high sensitivity without being disturbed by the external temperature.For the environmental compatibility and highly efficient capture of the toxic mercury ion,4-MPY is modified on the sensor surface forming a stable(4-MPY)-Hg-(4-MPY)structure due to the specific combination between the nitrogen of the pyridine moiety and the Hg+via multidentate N-bonding.Moreover,gold nanoparticles(AuNPs)are connected to the sensor surface through the(4-MPY)-Hg-(4-MPY)structure,which could play an important role for signal amplification.Under the optimized conditions,the limit of detection of the sensor for mercury ions detection in the solution is as low as 1.643×10^(-10)M(0.1643 nM),and the detection range is 1×10^(-9)M-1×10^(-5)M.At the same time,the mercury ion spiked detection with tap water shows that the sensor has the good selectivity and reliability in actual water samples.We develop a valuable sensing technology for on-time environmental Hg t detection and in-vivo point of care testing in clinic applications.

Folic Acid Status and Associated Factors for Pregnant Chinese Women—China,2015

Summary What is already known on this topic?Low folate status in pregnancy has been associated with multiple adverse pregnancy outcomes,including neural tube defects,congenital heart defects,fetal growth restriction,low birth weight,and preterm delivery.Low folate status is common in China,especially in northern areas.