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1.
Accid Anal Prev ; 195: 107404, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38042009

ABSTRACT

Over 20 % of global crash fatalities involve pedestrians, but pedestrian crash causation and pedestrian protection systems have not been thoroughly developed or reliably tested. To understand the causation characteristics of pedestrian crashes, 398 pedestrian crashes were extracted from the China in-depth accident study (CIDAS), and most of these crashes were aggregated into five scenarios. The two scenarios with the highest proportion of crashes were analyzed by the driving reliability and error analysis method (DREAM) to identify high-risk causation patterns. From these patterns, three main contributing factors were identified: 1) extremely environmental light disturbance; 2) distracted driving caused by drivers' own thoughts; 3) drivers violating pedestrian yield law. Based on these patterns and factors, a pedestrian protection system was designed. It consists of a forward vision sensor and radar to sense the environment and the three-stage autonomous emergency braking (AEB) algorithm to automatically avoid pedestrian collisions. Crash scenarios from CIDAS data were recreated in MATLAB Simulink to test the pedestrian protection system proposed in this study. This system was found to reduce pedestrian crashes by more than 90 %. The optimal parameters for three AEB stages were obtained, with decelerations of 0.2 g, 0.3 g, and 0.6 g. This study designed an active safety system based on causation analysis of the vehicle-pedestrian crashes and calibrated the AEB algorithm of it, thus providing reference and insight for further development of pedestrian protection systems.


Subject(s)
Accidents, Traffic , Pedestrians , Humans , Accidents, Traffic/prevention & control , Reproducibility of Results , Calibration , Protective Devices
2.
BMC Microbiol ; 22(1): 246, 2022 10 11.
Article in English | MEDLINE | ID: mdl-36221067

ABSTRACT

BACKGROUND: Azolla is a small floating fern living in symbiosis with nitrogen-fixing cyanobacteria and provides a variety of important ecosystem benefits. Previous studies have presented that Azolla harbors diverse bacteria that may play a key role in host fitness and productivity. However, the characteristics of endophytic bacteria inhabiting the phyllosphere of different species of Azolla have not yet been fully understood. RESULTS: In this study, the 16S ribosomal DNA (rDNA) V5-V7 region of bacteria was determined by Illumina high-throughput sequencing platform to study the diversity and richness of endophytic bacterial communities in the phyllosphere of five Azolla species collected from different countries. A total of 1150 operational taxonomic units (OTUs) were detected for the endophytic bacteria community. According to the α diversity indices, the diversity of bacteria was ordered as Azolla imbricata > A. pinnata > A. filiculoides > A. mexicana > A. caroliniana. The PCoA results displayed that the bacterial communities of A. mexicana and A. caroliniana shared the highest similarity, followed by the similarity between A. pinnata and A. imbricata, and they were significantly distinct from the community of A. filiculoides. The dominant bacteria of Azolla mainly belonged to the phylum of Proteobacteria, followed by Actinobacteria, Chlorobillobacteria, and Firmicutes. In detail, the relative abundance of Proteobacteria in A. imbricata was 52.23%, whereas it was more than 80.00% in the other four species of Azolla. Notably, Herbaspirillum (45.91%, 44.08%) and Methylophilus (29.97%, 37.96%) were the main genera inhabiting A. mexicana and A. caroliniana respectively. Ferrovibrio (18.54%) and Rhizobium (16.68%) were the dominant genera inhabiting A. filiculoides. The group of unidentified genera (41.63%, 44.92%) consisted most of the bacteria in A. imbricata and A. pinnata respectively. Further analysis suggested that the significant different bacteria identified in LDA Effect Size analysis existed Azolla species-specific patterns. CONCLUSIONS: In summary, all results suggested that the diversity and composition of the endophytic bacterial communities were different in Azolla species.


Subject(s)
Cyanobacteria , Ferns , Cyanobacteria/genetics , DNA, Ribosomal/genetics , Ecosystem , Ferns/genetics , High-Throughput Nucleotide Sequencing , Nitrogen , Proteobacteria/genetics , RNA, Ribosomal, 16S/genetics
3.
Aquat Toxicol ; 248: 106202, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35623198

ABSTRACT

Phytoremediation potential of Azolla in removal of nitrogen from wastewater has been promising. However, little is known about the response of Azolla to high concentrations of nitrogen. In this study, the responses of four Azolla species to different concentrations of total nitrogen ranging from 0 to 180 mg L-1 were examined. The responses varied among different species, and the high nitrogen-tolerant species A. caroliniana and A. microphylla could remove nitrogen from aqueous solutions with higher efficiencies. We further performed transcriptome analysis to explore the molecular mechanism underlying the response to high nitrogen stress in Azolla. RNA-seq analysis revealed a synergistic regulatory network of differentially expressed genes (DEGs) involved in nitrogen transport and metabolism in A. microphylla, mainly in the roots. Under high nitrogen treatment, the DEGs encoding nitrate transporters or nitrate transporter 1/peptide transporters (NRTs/NPFs), ammonium transporters (AMTs), nitrate reductase (NIA), nitrite reductase (NIR) and glutamine synthetases/glutamate synthases (GSs/GOGATs) were down-regulated, and the DEGs encoding glutamate dehydrogenases (GDHs) were up-regulated, suggesting that A. microphylla possessed high tolerance against excess nitrogen through down-regulation of nitrate and ammonium uptake and fine regulation of nitrogen assimilation in the roots. Our results provided a theoretical foundation for better utilization of Azolla for wastewater treatment.


Subject(s)
Ammonium Compounds , Ferns , Water Pollutants, Chemical , Ferns/metabolism , Gene Expression Profiling , Glutamates , Nitrogen/metabolism , Transcriptome , Water Pollutants, Chemical/toxicity
4.
AMB Express ; 11(1): 159, 2021 Nov 27.
Article in English | MEDLINE | ID: mdl-34837549

ABSTRACT

A traditional Chinese medicine formula based on the Coix seed and Lotus seed has been used as a general treatment of malnutrition, excessive fatigue, dysfunction of the spleen and stomach, and disorders of water transport in humans in China. However, there is limited information on its effects on the gut microbiota of piglets in vivo. In this study, the mix of Coix seed and Lotus were added the diet of forty weaned piglets (local piglets), and then evaluated it's affected on the gut microbiota of piglets and on the relations within the gut bacterial community. The results indicated that this traditional Chinese medicine formula (LM) and the extract of the traditional Chinese medicine formula (LMT) downregulated pH of succus gastricus and raised pH of the ileum, and LMT obviously decreased the feed conversion ratio. Further study showed LMT and LM also significantly increased the thick and long of gastrointestinal villi. And then, 16S ribosomal DNA sequencing revealed that groups LMT and LM have higher relative abundance of the genus Lactobacillus in the colon, succus gastricus, and jejunum, which are beneficial bacteria sold as dietary supplements to aid digestion or to augment health. Meanwhile, the relative abundance levels of Prevotellaceae, Alloprevotella, and Prevotella in the colon and Clostridium in succus gastricus and jejunum were lower. These experiments highlight the usefulness of the traditional Chinese medicine formula based on the Coix seed and Lotus seed for decreasing pH in succus gastricus, for improving the structure of intestinal villi and gut microflora, and then for achieving improvements in pig production performance.

5.
Mol Breed ; 41(2): 10, 2021 Feb.
Article in English | MEDLINE | ID: mdl-37309472

ABSTRACT

Trichomes are differentiated epidermal cells and can be found on above ground organs of nearly all land plants. Results from previous studies show that trichomes play important roles against a wide range of both biotic and abiotic stresses. By examining differences between parental genotypes of available populations, we identified a population of recombinant inbred lines showing clear segregation for trichome density and length. Assessing the F8 lines of the population growing in the field detected a major locus on chromosome arm 4BL. This locus was detected based the assessments of either fully expanded third leaves or flag leaves after anthesis. Based on the position of the QTL, an SSR marker was used to identify heterozygous plants at this locus from F5 lines derived from the same cross for the F8 population. Three pairs of near isogenic lines targeting this locus were obtained from these heterozygous plants. Difference in trichome length between the two lines with opposite alleles for each of these NIL pairs were similar to that between the two parental genotypes for the mapping populations, confirming that this single locus is mainly responsible for the trichome characteristics measured in this study. The allele with long and dense trichome is dominant as this characteristic was shown by the heterozygous individuals at this marker locus. Apart from the targeted locus, NIL pairs have highly homogeneous genetic backgrounds. Thus, the NILs could be invaluable in understanding the relationship between trichome density and resistance or tolerance to various biotic and abiotic stresses. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-021-01201-8.

6.
Animal Model Exp Med ; 3(1): 47-54, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32318659

ABSTRACT

BACKGROUND: Since the use of antibiotics in animal feed has become a critical concern worldwide due to severe threats to human health and environment, we are in need of finding alternatives to antibiotics in pig breeding, maintaining the health of pigs, and getting high-quality pork. As traditional Chinese herbs (TCH) are rich natural resources in China and show great benefits to human health we propose to transfer this abundant resource into animal production industry as additives. METHODS: Three groups of Chinese herbs (groups A, B, and C) were used as feed additives in the diet for pigs. In total 32 pigs were arranged in four groups (groups A, B, C, and control group, NC), fed in the same facility, eight pigs (one group) in each colony, free drinking, for 120 days. The feed:gain ratio (F/G), meat quality, total protein, and amino acid concentration of muscle were checked in the experiments. RESULTS: After 120 days of feeding, the feed:gain ratio (F/G) of pigs in groups A, B, and C was decreased 17.56%, 9.31%, and 13.86% compared with NC treatment, respectively. The diets supplemented with Chinese herbs improved meat quality, increased loin eye area (especially group A and C showed significant difference, P < .001), the total protein (increased ratio vs NC was A = 4.54%, B = 0.38% and C = 3.53%), amino acid concentration of muscle, increased the villus height:crypt depth ratio, and induced positive effects on serum biochemical parameters and immune function (serum TC and TG concentrations were significantly lower than those in the NC group, P < .05.). CONCLUSIONS: The use of Chinese herbal feed additives can reduce the cost of pig breeding and produce high-quality pock. The combination of these effects would contribute to better absorption ability of the intestinal tract and yield a better growth performance.

7.
AMB Express ; 9(1): 115, 2019 Jul 23.
Article in English | MEDLINE | ID: mdl-31338616

ABSTRACT

Coix seed has traditionally been used in traditional Chinese medicine to fortify the spleen and inhibit dampness, and has shown anticancer effects in humans. However, it is not known whether coix seed improves post-weaning growth performance and productivity, and the mechanism of interaction between coix seed and gut microbiota remains unknown. In this study, we established four groups: (i) control, (ii) antibiotic-fed, (iii) coix seed powder-fed, and (iv) coix seed extract-fed. The feeding experiment was conducted for 4 weeks. Coix seed extract significantly increased average weight gain and reduced the feed/meat ratio in weaned pigs, in addition to reducing the pH of their gastric juice. Further assays demonstrated that coix seed promotes an increase in the density and length of the gastrointestinal villi. Next, 16s sequencing of gut microbiota showed that coix seed significantly increased the abundance of phylum Bacteroidetes and genus Lactobacillus (p < 0.05) and reduced the abundance of phylum Prevotella (p < 0.05) in the gut microbiota. In contrast, the abundance of phylum Bacteroidetes and genus Lactobacillus decreased in the control group and antibiotic group, whereas the abundance of phylum Prevotella increased. Our findings indicate that coix seed improves growth performance and productivity in post-weaning pigs by reducing the pH value of gastric juice, increasing the density and length of gastrointestinal villi, and modulating gut microbiota. Thus, coix seed has good potential for use as a feed supplement in swine production.

8.
Ying Yong Sheng Tai Xue Bao ; 17(11): 2153-7, 2006 Nov.
Article in Chinese | MEDLINE | ID: mdl-17269345

ABSTRACT

The analysis on the dynamic changes of ecological footprint and ecological capacity in Fujian Province showed that in 1999-2003, the ecological footprint per capita in the Province increased from 1.428 hm2 to 1.658 hm2, while the ecological capacity per capita decreased from 0.683 hm2 to 0.607 hm2, with an increased ecological deficit year after year. The contradiction between the ecological footprint and ecological capacity pricked up gradually, and the ecological environment was at risk. There existed a severe imbalance in the supply and demand of ecological footprint per capita. The main body of the demands was grassland and fossil fuel, accouting for 55.74% - 63.43% of the total, while their supply only occupied 0.77% - 0.82% and next to nothing of the ecological capacity per capita, respectively. As a whole, the ecological footprint per ten thousand yuan GDP declined in the five years, indicating that the resources use efficiency in the Province was improved gradually. Based on the analysis of the present situation of the economic development and resources distribution in the Province, the strategies on reducing ecological deficit were put forward.


Subject(s)
Conservation of Natural Resources , Ecology , Ecosystem , Environmental Monitoring/methods , China
9.
Ying Yong Sheng Tai Xue Bao ; 16(6): 1056-60, 2005 Jun.
Article in Chinese | MEDLINE | ID: mdl-16180753

ABSTRACT

In this paper, a field experiment was conducted on a red soil of South China to study the effects of applying selenium fertilizer on the growth, forage quality and nitrogen-fixing ability of Chamaecrista rotundifolia. The results showed that applying 75, 150, 225 and 300 g Se x hm(-2) could increase the plant height, branch number, dry root weight and dry forage yield by 0.3% - 6.2%, 65.1% - 79.5%, 155% - 252% and 30.6% - 54.1%, respectively. The total nitrogen, total phosphorus and total potassium contents of plant were increased by 21.79% - 41.46%, 20.74% - 34.67% and 34.3% - 62.4%, respectively, and the raw protein, raw fat, raw fiber and amino acid contents were increased by 21.79% - 41.46%, 1.4% - 89.6%, 34.1% - 56.6% and 6.33% 63.24%, respectively. Among the 4 doses, 150 g Se x hm(-2) was the most effective and suitable application amount. The selenium content in plant after applying 300 g Se x hm(-2)(S4) was 0.695 mg x kg(-'), with an increase of 0.658 mg x kg(-1) compared to no selenium fertilization. There was a significantly positive correlation between plant selenium content and applied selenium (R2 = 0.9666**). The root nodule weight, number and nitrogenase activity in treatment 150 g Se x hm(-2)(S2) were respectively 131.7%, 114.3% and 1417.9% higher than those of no selenium fertilization. The correlation between applied selenium and nitrogenase activity was also significant (R2 = 0.9606*).


Subject(s)
Biomass , Chamaecrista/growth & development , Nitrogen Fixation , Selenium/pharmacology , Chamaecrista/metabolism , Fertilizers , Nitrogenase/metabolism
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