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An allocation scheme of water pollutant reduction is the key procedure to implement a watershed total maximum daily load (TMDL) program. In order to improve the equity for the allocation scheme of water pollutant load reduction, five indexes involved in allocation processes were selected from fields associated with society, environment, economics, and resources. The weights of these indexes were determined by using fuzzy optimization and entropy weight methods, and a multi-dimensional Gini coefficient-based allocation model for watershed point source pollutant load reduction was established. Corresponding constraint conditions were set to optimize the allocation scheme of point source pollutant load reduction. This model embodies the variability in importance of various indexes in the allocation process, and improves the equity and scientific basis of the allocation scheme. It is a reasonably ideal allocation model, and was used to allocate amino nitrogen load reductions in the Zhangweinan River basin. As validated by the soil and water assessment tool (SWAT) model, the optimized reduction scheme meets the water quality criteria for the relevant water functional area in the watershed in various target years. Authors in this paper made great efforts for the reduction allocation of watershed point source pollutant load in the watershed with intensive anthropogenic activities. The results provide a scientific basis and technical support for water environmental protection and sustainable uses of water resources in the Zhangweinan River basin.
Galanthamine is used as a strong reversible inhibitor of cholinesterase to increase acetylcholine sensitivity. Here, we sought to determine the effect of nitrogen (N) application on physiological and proteomic properties of Lycoris aurea (L. aurea) in order to explore the factors that influence galanthamine biosynthesis. A marked increase in plant growth was observed under absent nitrogen condition (0 mmol L-1 N), while a clear stunting of growth was seen under high nitrogen condition (3.57 mmol L-1 N). Levels of photosynthetic pigments also showed a preference for the absent nitrogen condition. The leaves and roots of absent nitrogen plants had significantly higher galanthamine content and lower contents of free amino acids and proline compared with those of control (0.75 mmol L-1 N). On the other hand, galanthamine content in L. aurea was significantly reduced with high nitrogen treatment. However, the contents of free amino acids and proline were increased with high nitrogen application, suggesting that these play important roles in the storage of nitrogen in L. aurea. Next, we carried out proteomic analysis of the leaves, bulbs and roots of L. aurea treated with nitrogen by two-dimensional gel electrophoresis. Using comparative proteomic strategies, we found 11 proteins that showed significant differences among the three groups. These proteins are involved in a variety of cellular processes including energy metabolism, scavenging oxygen free radicals, cytoskeleton stabilization, galanthamine biosynthesis and cellular homeostasis. Out of the 11 proteins, the level of phenylalanine ammonia-lyase was found to correlate with that of galanthamine biosynthesis.
Compared to angiosperms, conifers represent more complex genomes with larger giga-genome size. To detect large-scale single nucleotide polymorphisms (SNPs), whole genome sequencing of a conifer population is still unaffordable. In this work, we report the use of DNA specific-locus amplified fragment sequencing (SLAF-seq) for large-scale SNP detection in Chinese fir (Cunninghamia lanceolata (Lamb.) Hook), an ecological and economic important conifer in China. SLAF libraries of 18 parent clones of a Chinese fir 2.5 generation seed orchard were sequenced and a total of 117,924 SLAFs were developed. We detected 147,376 SNPs from these SLAFs; 146,231 of them represented simple nucleotide change in A/G, C/T, A/C, A/T, C/G or G/T. The most frequent SNPs occurred in C/T (34.3%), while the majority of SNPs (68.2%) belonged to transition events (A/G and C/T). Notably, all the sequenced samples had high portion (78.2–80.9%) of common SNPs indicating that the Chinese fir genomes tended to change its nucleotides at common loci. 48,406 informative SNPs were then successfully utilized to genotype the tested samples (n = 18) followed by a phylogenetic tree to clarify their genetic relationship. Furthermore, a set of very high linkage disequilibrium (0.51–1.00) were identified from these informative SNPs. In brief, our work demonstrated that SLAF-seq is an alternative and cost-effectively high-throughput approach for large-scale SNP exploitation in Chinese fir. While the obtained SNPs offer useful marker resource for further genetic and genomic studies and will be helpful for Chinese fir breeding programs.
The success of a tree breeding program largely depended on the available genetic variability of the germplasms. Our present study aimed to assess the phenotypic variation and DNA variability using sequence-related amplified polymorphism (SRAP) markers among 50 Cunninghamia lanceolata (Chinese fir) genotypes. Extensive phenotypic variations (p < 0.05 or 0.01) were found for all the growth and wood property traits (height, diameter at breast height, stem volume, and wood basic density, hygroscopicity, heart-wood ratio, tracheid length, tracheid diameter and tracheid length-diameter ratio) with coefficients of variation spanning from 6.8 to 31.3%. At the DNA level, thirty-five SRAP primer combinations produced 498 bands with 89.4% polymorphism across genotypes; moreover, the Nei’s gene diversity was detected to be ranged between 0.204 and 0.373 (mean = 0.279), while the Shannon’s Information Index stretched from 0.324 to 0.555 with an average value of 0.427. Significance (p < 0.01) of the variability of SRAP polymorphism among genotypes was further demonstrated by AMOVA. These results indicated a relatively high level of genetic diversity in genotypes. The SRAP’ dendrogram additionally revealed that these genotypes could be split into 7 clusters with higher discriminating capacity over that of phenotype. Notably, a total of 99 statistically significant (p < 0.05) marker-trait associations related to the growth and wood property traits were identified. These marker-trait associations corresponded to 77 different SRAP markers with R2 (percentage of the phenotypic variation explained by marker) ranging from 8.3 to 26.4%.
In recent years, biochar, a new environmentally functional material, has received widespread attention as a soil amendment for its special structures and characteristics, such as improving soil texture and increasing crop yield. However, controversies still exist for the effects of biochar addition to soil nitrogen(N) cycles. This study focuses on the influences of 350ºC peanut biochar application on N mineralization in abandoned orchard soil during a 46-day incubation. The treatments contained control (CK), 1% biochar (BC), and 3% biochar (BC). Results showed that 350ºC peanut biochar increased soil pH and EC, but decreased soil urease activities significantly. Biochar decreased soil net-mineralized N significantly, and a higher biochar addition content resulted in lower soil mineralized N concentration. NO3–-N content accounted for more than 94% of soil inorganic N for all three treatments during the entire incubation time, while the presence of biochar did not change this characteristic. Conclusions indicated that the addition of 350ºC peanut biochar significantly inhibited orchard soil N mineralization in a short time by altering soil physical and chemical properties.
Under accelerated urbanization and high-intensity human activities, the natural wetlands distribution area (NWDA) in Minjiang River estuary faces the great challenge of a deteriorative urban thermal environment. This work aims to analyze the impact of land use/land cover (LULC) on the urban thermal environment and model wetland surface temperature disturbance characteristics during the process of urbanization. The study utilized the following methodological steps: (1) mapping of LULC spatial and temporal distribution through photo interpretation; (2) applying the mono-window algorithm to obtain the spatiotemporal patterns of land surface temperature (LST); (3) examining the correlation between LST and different LULC classes, normalized difference vegetation index (NDVI), normalized difference moisture index (NDMI), and normalized difference impervious surface index (NDISI); and (4) exploring wetland surface temperature characteristics based on profile analysis and regression models. The results showed that the LST pattern depended on the LULC distribution; the high LST zones were mainly observed in the center of Fuzhou city, and the low LST zones were mainly observed in forest and river areas. Moreover, the urban thermal environment was influenced by both LULC classes and urban growth types. Finally, the positive relationship between LST and NDISI indicated an amplifying effect of the impervious surface for wetland surface temperature, while vegetation with high liquid water attenuated the regional high temperature. The obtained conclusions are expected to be beneficial in improving the design and management of the urban thermal environment.
γ-amino butyric acid (GABA) is the main inhibitory neurotransmitter in the mammalian central nervous system. GABA is also found in many peripheral tissues, where it has important functions during development. Here, we identified the existence of the GABA system in spermatogonial stem cells (SSCs) and found that GABA negatively regulates SSC proliferation. First, we demonstrated that GABA and its synthesizing enzymes were abundant in the testes 6 days postpartum (dpp), suggesting that GABA signaling regulates SSCs function in vivo. In order to directly examine the effect of GABA on SSC proliferation, we then established an in vitro culture system for long-term expansion of SSCs. We showed that GABAA receptor subunits, including α1, α5, β1, β2, β3 and γ3, the synthesizing enzyme GAD67, and the transporter GAT-1, are expressed in SSCs. Using phosphorylated histone H3 (pH3) staining, we demonstrated that GABA or the GABAAR-specific agonist muscimol reduced the proliferation of SSCs. This GABA regulation of SSC proliferation was shown to be independent of apoptosis using the TUNEL assay. These results suggest that GABA acts as a negative regulator of SSC proliferation to maintain the homeostasis of spermatogenesis in the testes
Diabetic population were reported more likely to suffer carriage and infection with Staphylococcus aureus (S. aureus) and methicillin-resistant Staphylococcus aureus (MRSA) than non-diabetic population. We aim to elucidate the prevalence and characteristics of S. aureus and MRSA nasal carriage among diabetic population in the United States National Health and Nutrition Examination Survey, 2001–2004. Univariate analyses were conducted using Chi-square test, Fisher’s exact probability test or student t test, as appropriate. Multivariate analysis using logistic regression was conducted to assess the association between influencing factors and S. aureus and MRSA nasal carriage. 1010 diabetic participants were included in the study. The prevalence of S. aureus and MRSA nasal carriage were 28.32% and 1.09%, respectively. After the logistic regression, ever had a painful sensation or tingling in hands or feet past three months (Odds Ratio [OR] = 0.359, 95% Confidence Interval [CI], 0.146–0.882) was significant among S. aureus nasal carriage and gender (OR = 3.410, 95% CI, 1.091–10.653) was significant among MRSA nasal carriage. The proportions of staphylococcal enterotoxin (SE) A, SEB, SEC, SED, Toxic-shock syndrome toxin-1, and Panton Valentine Leukocidin toxin among S. aureus strains were 18.75%, 3.13%, 12.50%, 15.63%, 28.13%, and 9.38%, respectively. 63.63% of MRSA strains were community-acquired, 27.27% were hospital-acquired, and 9.09% were non-typeable. Diabetic patients might be more likely to carry S. aureus and MRSA in the United States. Improving hand hygiene compliance, reducing antibiotic overuse, screening for carriers, and decolonization are recommended to reduce the spread of S. aureus and MRSA, especially in community.
As a member of tyrosinase-related family, tyrosinase-related protein-1 (TYRP1) has been reported to play an important role in melanin biosynthetic pathway in some species, but little is known about its role in goat. In this study, almost complete goat TYRP1 gene (17554 bp, HMO70243) encompassing complete CDS was identified, the coding region amounting to 1614 bp, distributed in 7 exons (2-8), and intron 5 was found to possess GC-AG as its splice sites. Dozens of SNPs as well as simple sequence repeat (SSR) motifs were detected in goat TYRP1 gene, in which 4 SSR motifs in intron 5 are combined in a tandem. Correlation analysis showed the allele A to be advantageous compared to C at site g.1263A>C and allele C compared to T at g.1428C>T, implyimg that haplotype AC is in favour of eumelanin biosynthesis, and haplotype CC is in favour of pheomelanin formation.Marked deficiency of heterozygotes occurred in Nanjiang Yellow Goat Black strain and Nanjiang Yellow Goat Fast Grow strain, indicating the high inbreeding in both strains.
Peptidylarginine deiminase (PAD) catalyzes the post-translational modification of protein through the conversion of arginine to citrulline in the presence of calcium ions. Human, similar to rodents, has four isoforms of PAD (type I, II, III and IV/V), each of which is distinct in substrate specificity and tissue specific expression. In our large-scale sequencing project, we identified a new human PAD cDNA from a human fetal brain cDNA library. The putative protein encoded by this cDNA is designated hPADVI. Expression analysis of hPADVI showed that it is mainly expressed in adult human ovary and peripheral blood leukocytes. We conclude that hPADVI may be orthologous to mouse ePAD, basing on sequence comparison, chromosome localiza­tion and exon-intron structure analysis. PAD-mediated deimination of epithelial cell keratin resulting in cytoskeletal remodeling suggests a possible role for hPADVI in cytoskeletal reorganization in the egg and in early embryo development. This study describes a new important member of the human PAD family.
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