Genetic structure and trait variation within a maple hybrid zone underscore North China as an overlooked diversity hotspot.

Tertiary relict flora in East Asia can be divided into northern and southern regions. North China is a diversity hotspot because it can be the secondary contact zone of ancient lineages from the two regions. To test the extent of ancient lineages hybridization and distinguish between the putative species pair Acer pictum subsp.

Testing environmental Kuznets curve hypothesis: considering the impact of Sino-US trade on three main industries in China.

To achieve carbon neutrality and carbon reduction goals, China needs to consider industrial structure and trade. This study aims to test the validity of environmental Kuznets curve (EKC) hypothesis at the industry level in China and study the different impact of Sino-US trade in intermediate goods and trade in final goods on China's environment. To do so, we used the annual data of China's 25 sectors in 1990-2015 and classified 25 sectors into three main industries.

Phylogeography of (Magnoliaceae) Reveal Multiple Refugia With Ample Gene Flow in Northeast China.

Temperate conifers and broadleaved mixed forests in northeast China are ideal to investigate the genetic consequences of climate changes during the last glacial maximum (LGM), 29 - 16 kya. As previous studies were focused on tree species with long generation time; here, the evolutionary history of , a climber species with a generation time of five years, was investigated using chloroplast DNA (cpDNA), nuclear single copy gene (nSCG), and nuclear single sequence repeats (nSSRs, i.e.

Twenty-seven low-copy nuclear primers for (Lauraceae): A Tertiary relict species in East Asia.

Premise Of The Study: To investigate a more detailed evolutionary history of (Lauraceae) and other species, polymorphic low-copy nuclear primers were developed.

Methods And Results: Unigenes of the transcriptome greater than 800 bp in length were randomly chosen for initial design of 168 primers. Agarose gel electrophoresis and Sanger sequencing were used to select low-copy nuclear genes.

Contrasting genetic patterns between two coexisting Eleutherococcus species in northern China.

Climate oscillations are the key factors to understand the patterns in modern biodiversity. East Asia harbors the most diverse temperate flora, largely because an extensive terrestrial ice cap was absent during repeated Pleistocene glaciation-interglacial cycles. Comparing the demographic histories of species that are codistributed and are close relatives may provide insight into how the process of climate change influences species ranges.

Evolutionary history of a widespread tree species Acer mono in East Asia.

East Asia has the most diverse temperate flora in the world primarily due to the lack of Pleistocene glaciation and the geographic heterogeneity. Although increasing phylogeography studies in this region provided more proofs in this issue, discrepancies and uncertainty still exist, especially in northern temperate deciduous broad-leaved and coniferous mixed forest region (II). And a widespread plant species could reduce the complexity to infer the relationship between diversity and physiographical pattern.

[Change trend of vegetation cover in Beijing metropolitan region before and after the 2008 Olympics].

The MODIS-NDVI data from 2000 to 2009 were used to analyze the temporal dynamics and spatial distribution of the vegetation cover in the Beijing metropolitan region before and after the 2008 Olympics. During the study period, the proportion of the significantly increased pixels of NDVI occupied 20.7% while that of the significantly decreased pixels only occupied 4.

[Methods and applications of population viability analysis (PVA): a review].

With the accelerating human consumption of natural resources, the problems associated with endangered species caused by habitat loss and fragmentation have become greater and more urgent than ever. Conceptually associated with the theories of island biogeography, population viability analysis (PVA) has been one of the most important approaches in studying and protecting endangered species, and this methodology has occupied a central place in conservation biology and ecology in the past several decades. PVA has been widely used and proven effective in many cases, but its predictive ability and accuracy are still in question.

Prevalence of 3-rooted first permanent molars among a Shanghai Chinese population.

Objectives: This study aimed to assess the prevalence of 3-rooted mandibular first molars among a Shanghai Chinese population by using periapical radiographs.

Methods: A total of 510 patients possessing both mandibular first molars were selected. The radiographs of these cases were evaluated under optimal conditions using double magnifying glasses.

[Land use pattern and its dynamic changes in Amur tiger distribution region].

Land use and land cover change has been the primary cause for the habitat loss and fragmentation in the distribution region of Amur tiger (Panthera tigris altaica). Based on the spatiotemporal changes of land use and land cover in the distribution region, as well as their effects on the population dynamics of Amur tiger, this paper analyzed the development process and its characteristics of the main land use types (agricultural land, forest land, and construction land) in this region, with the land use change history being divided chronically into three distinctive periods, i.e.

[Net primary productivity of Leymus chinensis steppe in Xilin River basin of Inner Mongolia and its responses to global climate change].

CENTURY model was utilized to simulate the annual aboveground net primary production (ANPP) of Leymus chinensis steppe, a dominant community type in Xilin River basin of Inner Mongolia steppe region. The results showed that the model performed reasonably well in predicting the dynamics of the ANPP. The scenario-based simulations indicated that though the variations of air temperature and precipitation due to global climate change as well as the elevated CO2 would significantly affect the dynamics of the ANPP, precipitation was the key affecting factor.

Ecosystem health assessment of the Jinghe River Watershed on the Huangtu Plateau.

An improved Costanza model was developed to assess the health of the Jinhe River Watershed ecosystem. The watershed is located at the center of the Huangtu Plateau in China and has suffered a severe disturbance in the last few decades. Three indicators including vigor, organization, and resilience were calculated respectively by merging ground-based observations with remotely sensed data on a watershed scale.

[Quantitative monitoring of gully erosion in hilly-gully area of Loess Plateau based on aerial images].

Based on the aerial photographs in 1979 and 1993, and by using geographical information system (GIS) techniques, the digital elevation models (DEM) and digital orthophoto map (DOM) were constructed from the geomorphic changes in a chosen gully in the Loess hilly-gully area, and the spatial difference of the changes and their key affecting factors were analyzed. The results indicated that from 1979 to 1993, the gully head advanced actively (with a length of 8.5 meters and an erosion rate of 481.

[Genetic diversity of Hippophae rhamnoides L. sub-populations on loess plateau under effects of varying meteorologic conditions].

The genetic diversity and genetic differentiation of eight Hippophae rhamnoides L. populations in eastern Gansu Province, as well as the effects of varying meteorologic conditions on them were assessed by using inter-simple sequence repeat (ISSR) molecular marker method. A total of 240 individuals in the populations were sampled.

[An individual-based catchment scale forest dynamic model].

In this paper, an individual-based catchment scale forest dynamic model was developed, and applied to a 400 years simulation of a real catchment. The simulation included pretreatment of topographic data, running of modified MTCLIM, and simulation of forest dynamics. The development and validation processes of this model were described, and the details of the model, including the application of GIS and the parameterization of climate and physiological factors, were presented.

[The relationship between soil respiration and the temperature at different soil depths in subalpine coniferous forest of western Sichuan Province].

By using closed chamber IRGA technique, a continuous measurement of soil respiration rate was conducted in the subalpine natural coniferous forest mainly composed of Abies faxoniana in the eastern edge of Qinghai-Tibet Plateau, with the temperature at different soil depths (0, 5, 10, 15 and 20 cm) measured simultaneously. Base on the measurements, the quantitative relationships between soil respiration rate and the temperature at different soil depths were explored, and the results showed that the soil respiration rate in the forest had remarkable diurnal and seasonal changes, being the highest at 12:00-14:00 and in August, and the lowest at 8:00-10:00 and in November, which were accorded with the dynamics of soil temperature. Soil respiration rate had a significant exponential correlation with the temperature at different soil depths, and the highest correlation occurred at the soil depth of 15 cm (R2 =0.

[Study on exopolysaccharides produced by planktonic and attached Streptococcus sobrinus].

Purpose: To elucidate the amount of exopolysaccharides produced by Streptococcus sobrinus when cultivated at different conditions.

Methods: S. sobrinus was grown in TS broth and was allowed to attach to the cover glass surface to form bioflims.

[Empirical study on non-point sources pollution based on landscape pattern & ecological processes theory: a case of soil water loss on the Loess Plateau in China].

Non-point sources pollution is one of main pollution modes which pollutes the earth surface environment. Aimed at soil water loss (a typical non-point sources pollution problem) on the Losses Plateau in China, the paper applied a landscape patternevaluation method to twelve watersheds of Jinghe River Basin on the Loess Plateau by means of location-weighted landscape contrast index(LCI) and landscape slope index(LSI). The result showed that LSI of farm land, low density grass land, forest land and LCI responded significantly to soil erosion modulus and responded to depth of runoff, while the relationship between these landscape index and runoff variation index and erosion variation index were not statistically significant.

Geometrically kinetic competition mechanism to shape control on digenite nanocrystals with silica vapor in APCVD.

We report shape control synthesis of digenite nanosheets (growing perpendicular to the <111> direction) and nanowires (growing along the <111> direction) through control on the silica vapor pressure in the system. Critical vapor pressures for silica sheath initialization and crystal shape maintenance are determined in two sets of experiments. The geometrically kinetic competition (GKC) mechanism, which was first proposed in our former work (J.

Silica-sheathed pyrrotite nanowires: Synthesis and mechanism.

We have studied the growth of silica-sheathed 3C-Fe7S8 products on silicon substrates with FeCl2 and sulfur precursors at the temperature region of 600-800 degrees C. On the basis of the crystal structure of Fe7S8, we have proposed a model including the kinetic competition of the adsorption of silica species on Fe2-Fe3-Fe4 units at the 4Fe layer and on the Fe2-Fe3-Fe4-Fe5 units parallel to the c-axis. Using this model, we have not only explained all the experimental phenomena but also especially prepared Fe7S8 nanowires at 650 degrees C by introducing water into the reaction system.

Synthesis of CdSe, ZnSe, and ZnxCd1-xSe nanocrystals and their silica sheathed core/shell structures.

Uniform ZnxCd1-xSe nanocrystals have been prepared at the artificially designed water-oil interface using Na2SeO3, Cd(NO3)2, and Zn(NO3)2 as precursors. The chemical composition and band gap of the ZnxCd1-xSe nanocrystals can be adjusted via different combinations of source material. The coating of a SiO2 shell could transform the hydrophobic particles into hydrophilic particles.

Formation of disperse nanoparticles at the oil/water interface in normal microemulsions.

An artificial oil/water interface was created in normal microemulsions. Various well-dispersed inorganic nanoparticles were successfully fabricated at this micelle interface, and a "hot liquid annealing" process was used to crystallize the products. Owing to the large solubility of the source materials in the water phase, the colloidal nanoparticles can easily be prepared on a large scale.

[Preventive effect of genistein on malignant transformation of oral leukoplakia].

Objective: To investigate the preventive effect of genistein on the malignant transformation of oral leukoplakia in hamster cheek pouch.

Methods: Sixty male Syrian golden hamsters were randomly divided into 4 groups, with two of 20 and two of 10. DMBA solution (0.

[On the relationship between exopolysaccharides and Actinomyces viscosus in biofilms].

Objective: To elucidate the biofilm structure of Actinomyces viscosus and the spatial distribution of exopolysaccharides in it.

Methods: The Actinomyces viscosus biofilm was made by allowing bacteria to attach to the cover glass surface. The biofilm structure and exopolysaccharides distribution at 24 hours were stained with Fluorescein, BODIPY and Calcofluor respectively and were visualized by confocal laser scanning microscopy (CLSM).