1. Much recent research has explored how global warming and increased nitrogen (N) deposition, two important components of global environmental changes, influence the structure and functioning of natural ecosystems. However, how ecosystem dynamics respond to the combination of long-term warming and N enrichment remains largely unexplored. 2. We investigated the impact of warming and N addition on the temporal stability of plant communities in a decade-long field experiment, conducted in a desert steppe in northern China, using a split-plot design with warming as the main-plot factor and N addition as the split-plot factor. 3. Long-term warming and N addition had additive, negative effects on plant community stability. A warming-induced decrease in species richness was not a significant driver of decreased community stability, which was instead driven by the decreased stability of dominant species under warming. On the other hand, a N-induced decrease in community stability was ascribed to both decreased stability of dominant and common species and decreased asynchronous population dynamics under N addition. 4. Synthesis. Our results suggest that ongoing anthropogenic environmental changes may have appreciable consequences for the stability of natural grassland functions and services while also highlighting the different mechanisms associated with the similar effects of climate warming and increased N deposition on grassland community stability.
Solid state fermentation with different lignocellulolytic materials as inducers was used for lignocellulolytic enzyme production in this study. Pleurotus ostreatus strains were assessed by measuring laccase, CMCase, and xylanase activities. The secretion potential of the lignocellulolytic enzymes by wild and cultivated strains was analyzed for the first time. The wild and cultivated strain showed their unique capacities for secreting lignocellulolytic enzymes on solid-state fermentation with different lignocellulosic materials. The wild P. ostreatus strain preferred corncob for the secretion of laccase and xylanase activity, but the cultivated strain preferred poplar sawdust. The wild strain and cultivated strain showed a consistent preference for poplar sawdust for the secretion of CMCase activity. The wild strain was advantageous because it achieved the maximum hydrolytic enzyme activities within a short time period. Poplar sawdust and corncob were conducive to laccase secretion by the wild or cultivated strains and the rapid accumulation of laccase on solid-state fermentation. Additionally, continuous, stable laccase production was an extremely important advantage by solid-state fermentation of poplar sawdust, particularly in the wild strain. These findings are helpful in selecting the appropriate strain that corresponds to suitable lignocellulosic materials. The optimization of integrated industrial lignocellulolytic enzyme production can also be achieved.
A novel multistage algorithm is proposed for the automatic segmentation of microcalcification clusters (MCCs) in digital mammography. First, a previously reported tree structured nonlinear filter is proposed for suppressing image noise, while preserving image details, to potentially reduce the false positive (FP) detection rate for MCCs. Second, a tree structured wavelet transform (TSWT) is applied to the images for microcalcification segmentation. The TSWT employs quadrature mirror filters as basic subunits for both multiresolution decomposition and reconstruction processes, where selective reconstruction of subimages is used to segment MCCs. Third, automatic linear scaling is then used to display the image of the segmented MCCs on a computer monitor for interpretation. The proposed algorithms were applied to an image database of 100 single view mammograms at a resolution of 105 microns and 12 bits deep (4096 gray levels). The database contained 50 cases of biopsy proven malignant MCCs, 8 benign cases, and 42 normal cases. The measured sensitivity (true positive detection rate) was 94% with a low FP detection rate of 1.6 MCCs/image. The image details of the segmented MCCs were reasonably well preserved, for microcalcification of less than 500 microns, with good delineation of the extent of the microcalcification clusters for each case based on visual criteria.
The blood samples were obtained from 106 unrelated healthy individuals from Yili Uigur ethnic autonomous region, Xin Jiang Province of China. Genomic DNA was extracted using the Chelex100 protocol as described by Walsh et al. (1). PCR for 15 STRs was performed in multiplex reaction using AmpFLSTR Identifiler kit; 0.9 µL (2 ng/µL) genomic DNA samples were amplified in a total reaction volume of 10 µL along with 2.9 µL deionized water, 4 µL dNTP, 0.2 µL AmpliTaqGold DNA polymerase, and 2.0 µL primer set. Thermal cycling was conducted with the below conditions: 95°C for 11 min; 28 cycles of 94°C for 60 sec, 59°C for 60 sec, 72°C for 60 sec; and a final extension of 60°C for 45min. Detection and genotyping of all PCR products were accomplished using ABI3100 DNA Genetic Analyzer (Applied Biosystem). Allele designation was done using GeneScan3.7 and Genotyper3.7.
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