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1

Research on impact of different environmental regulation tools on energy efficiency in China

100%
Li R., Sun T.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 6
2

Removal of sulfa antibiotics in low-temperature water using scoria

81%
Li R., Zhang Y., Wang J., Qian H.
Polish Journal of Environmental Studies
|
2017
|
tom 26
|
nr 5
Scoria, a natural silicate mineral, was used for the adsorption removal of antibiotics from water. The kinetics of adsorption were studied during the experiment and the results showed that the adsorption of three antibiotics (sulfathiazole (ST), sulfamethazine (SM2), and sulfamethoxazole (SMX)) by scoria fit the Freundlich isotherm well. Additionally, batch experiment data were fitted using pseudo first-order and pseudo second-order equations, and the calculated capacities for the three antibiotics were 0.7688, 0.7242, and 0.6341mg/g, respectively. Moreover, the effects of various water chemistry factors on the removal of the three antibiotics were explored, and Fe²⁺ and Mg²⁺ were found to promote the adsorption. The alkalinity and hardness of water both had significant effects on absorption of the three antibiotics by scoria. The carbon content of scoria increased significantly, and energy dispersion spectrum analysis showed that it could remove three sulfa antibiotics from low-temperature (10°C) water effectively. Overall, scoria is an effective natural material for purifying low-temperature water polluted with ST, SM2, and SMX.
3

Changes in selected biochemical parameters (including FGF21) during subclinical and clinical ketosis in dairy cows

81%
Chen Y., Dong Z., Li R., Xu C.
Medycyna Weterynaryjna
|
2018
|
tom 74
|
nr 11
Negative energy balance (NEB) is a common pathological cause of ketosis. As the major organs of lipid metabolism, the liver and fat tissue take part in regulating lipid oxidative capacity and energy demands, which is also a key metabolic pathway that regulates NEB development during the perinatal period. Fibroblast Growth Factor 21 (FGF21) is a novel metabolic regulator involved in the control of fatty acid oxidation and lipid metabolism during a prolonged negative energy balance. Our study determined a correlation between serum FGF21 and β-hydroxybutyric acid (BHBA) levels in dairy cows with ketosis. We used sixty cows with low milk yield, abnormal glucose metabolism, and ketosis. Serum FGF21 and BHBA levels were measured using commercial kits. Serum FGF21 increased with increasing BHBA levels up to 1.6 mmol/L. At BHBA levels > 1.6 mmol/L, FGF21 decreased. Serum FGF21 levels were positively associated with BHBA levels, particularly in dairy cows with subclinical ketosis (r = 0.647, P < 0.01). At BHBA levels between 1.2 mmol/L and 1.6 mmol/L, FGF21 was more closely correlated with BHBA than with other metabolic parameters. At BHBA levels > 1.6 mmol/L, the association between FGF21 and BHBA was not significant. In conclusion, our results show that FGF21 was closely related with SK in cows. FGF21 may be a promising regulator in the prevention of subclinical ketosis.
4

Modelling and optimisation of vacuum collection system for cruise ship kitchen garbage

81%
Du J., Li R., Wu X., Zhao H.
Polish Maritime Research
|
2020
|
tom 27
|
nr 1
Pollution of the marine environment by ship garbage is an urgent problem to be solved at home and abroad. The ship kitchen garbage vacuum collection system is a new environmental protection scheme for garbage disposal. It has many advantages, such as using a pipeline instead of manual operation, creating high-level sanitary conditions, realising completely closed garbage collection and transportation, eliminating cross-pollution, saving space and so on. In this paper, the system is modelled, and the calculation of pipeline pressure loss, the vacuum degree of the vacuum tank and the energy consumption of the system are briefly introduced. In order to reduce the energy consumption, an algorithm for the emptying and discharging port is presented. In order to solve the problem of optimising relevant parameters, the vacuum transport mechanism of garbage is studied based on an optimisation model of the pipe network, and the experimental platform of a simulation device is set up. In engineering, this is of great significance to the design of cruise ship garbage collection and treatment systems and the development of supporting technology
5

Trends, abrupt changes, and periodicity of streamflow in Qinghai province, the northeastern Tibetan Plateau, China

71%
Chang B., He K., Li R., Wang H., Wen J.
Polish Journal of Environmental Studies
|
2018
|
tom 27
|
nr 2
The Qinghai-Tibet Plateau is a more sensitive area of climate change and fragile zone of ecological environment. Qinghai Province is an important component of the Qinghai-Tibet Plateau, and the study of streamflow in the province is of great significance for understanding the situation of water resources. Based on hydrological data of hydrological stations in Qinghai, the spatiotemporal variations of streamflow from 1956 to 2013 were analyzed by Mann-Kendall analysis and Morlet wavelet analysis. The results indicated that the annual streamflow of the Yangtze River basin, Qaidam basin, Qinghai Lake basin, and Lantsang River basin showed significantly increasing trends during 1956-2013, while the Yellow River basin showed no significant trends or downward trends. Changes in precipitation, glacier melt, and snowmelt caused by climate warming might be a major driver of changes of streamflow in the source regions of the Yangtze River and Lantsang River basins. The trend variations of flow in the Yellow River basin may be affected by precipitation, evaporation caused by increased temperature, and anthropogenic impacts. The abrupt changes of streamflow at Tuotuohe, Delingha, and Nachitai stations were mainly in the early 2000s, while the abrupt changes of streamflow in Zhimenda station, stations in the Yellow River basin, Qinghai Lake basin, and Lantsang River basin appeared primarily in the early 1960s and the early 2000s. Most of the streamflow in Qinghai Province was abundant after about 2007, and the dominant periods with low frequency fluctuation (about 12 years) and inter-decadal (about 44 years) oscillations in Zhimenda and Tangnaihai stations and low frequency fluctuation (about five years) in other stations.
6

The crucial role of SEMA3F in suppressing the progression of oral squamous cell carcinoma

71%
Liu Y., Li R., Yin K., Ren G., Zhang Y.
Cellular and Molecular Biology Letters
|
2017
|
tom 22
7

Survival strategies of Ammopiptanthus mongolicus and Zygophyllum xanthoxylon in saline and drought environments, northwest China

71%
Shen X., Chai M., Xiang J., Li R., Qiu G.
Acta Physiologiae Plantarum
|
2015
|
tom 37
|
nr 10
Ammopiptanthus mongolicus and Zygophyllum xanthoxylon are typical plants in the West Ordos National Natural Reserve of Inner Mongolia, China. The populations of A. mongolicus had few young individuals and senesced. However, Z. xanthoxylon was growing well in the habitat of A. mongolicus. In addition, there is little information to compare their seed germination and seedling growth under combined salt and drought environments. In order to exploring the reason for the actuality, a study was conducted to quantify the interactive effects of salinity and drought stresses on seed germination and seedling growth of A. mongolicus and Z. xanthoxylon and then to compare the survival strategies of both shrubs. The experiment consisted of seven gradient concentrations of salinity (0, 0.3, 0.6, 0.9, 1.2, 1.5 and 1.8 % NaCl) in each of the six drought stress levels (0, -0.2, -0.4, -0.8, -1.6 and -2.0 Mpa polyethylene glycol). As expected, combined salinity and drought stresses had significant (P\0.05) interactive effects on seed germination of the two tested shrubs. There was significant decrease in these indices, in response to increased salt and/or drought stresses. The higher germination rate and shorter germination duration were detected for A. mongolicus, which may lead to the loss of seed bank. In addition, the radicle length of A. mongolicus (0–2.3 cm) was shorter than that of Z. xanthoxylon (0–14.6 cm), indicating less resistance of seedlings to the volatile conditions in the surface of arid soil. The stepwise regression analysis showed that salinity was the dominant influencing factor and followed by drought in seed germination and seedling growth under salt–drought mixed stress.
8

Effects of land use change of sloping farmland on characteristic of soil erosion resistance in typical karst mountainous areas of Southwestern China

71%
Li R., Wu Q., Zhang J., Wen Y., Li Q.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 4
With the implementation of ecological projects such as the Grain-for-Green Project, rocky desertification control and comprehensive control of soil and water loss for sloping farmland, ecological environment of karst mountainous areas in southwest China has been improved significantly, but soil and water loss of sloping farmland is still an important ecological and environmental problem in this region. In this paper we took a typical karst rocky desertification mountainous area, Jinlan Demonstration Area, as the study area located in Qianxi County, Guizhou Province. On the basis of a previous experimental demonstration of grass planting and afforestation on sloping farmland (planted in 2014), the sample plot method was used to obtain soil samples and soil shearing test piece in 2017, and soil shear strength and soil erodibility factor (K) were measured by direct shear method and hydrometer method in order to study the effect of sloping farmland converted to abandoned land, pastureland and agroforestry on soil erosion resistance. Results showed that the soil sheer strength was no obvious change and soil erodibility was no significant difference (P>0.05) in sloping farmland with the level of rocky desertification becoming more serious; soil sheer strength greatly increased after sloping farmland was abandoned, ultimate shear strength τ300 was increased by 65.5%, and K was significantly different (P<0.05) after 10 years; in the process of sloping farmland converted to pastureland, the soil ultimate shear strength τ300 was increased by 34.55% and K decreased significantly (P<0.05), which indicated that the effect of grass planting on improving soil erosion resistance of sloping farmland was obvious; in the process of sloping farmland converted to agroforestry, soil erosion resistance was also enhanced, soil shear strength was increased, and K was decreased (it did not reach the significant level, P>0.05). Based on the preliminary results of this paper, we think both grass (tree) planting and land abandonment could improve soil erosion resistance and reduce soil erosion risk, whichare feasible non-engineering measures for soil and water conservation in the karst area of southwestern China.
9

Vertical distribution of nearshore flow velocity

71%
Li C., Fu X., Li R., Dai L., Chen P.
Polish Maritime Research
|
2016
|
tom 23
|
nr Special Issue S1
In this paper, a new exponential formed vertical distribution of nearshore flow velocity is constructed, which is simpler in form and more suitable for engineering application. The physical meaning of the new formula is more specific than that of Soulsby. Compared with those logarithmic formed ones, the new one does not need the maximum velocity and only needs the mean velocity in vertical, which gives it better engineering practicability. Apply the new formula to Jiangsu coastal area and compare the results with that of Soulsby whose results show the new formula agrees better with the measured flow velocity, which reasonably reflects the basic principles of vertical distribution of flow velocity
10
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Content available

Development of a rapid immunochromatographic assay for detection of antibodies against porcine epidemic diarrhea virus

61%
Li R., Tian X., Yu Y., Qiao S., Wang Z., Ma J.
Polish Journal of Veterinary Sciences
|
2018
|
tom 21
|
nr 1
11

Growth and physiological responses to copper stress in a halophyte Spartina alterniflora (Poaceae)

61%
Chai M., Shi F., Li R., Qiu G., Liu F., Liu L.
Acta Physiologiae Plantarum
|
2014
|
tom 36
|
nr 03
A study quantifying the effects of different copper (Cu) concentrations (50, 200, 800 and 1,000 mg kg⁻¹ Cu) on Cu bioaccumulation and physiological responses of Spartina alterniflora was conducted. Plant biomass and Cu accumulation were determined. Plant height, tiller number, chlorophyll, leaf electrolyte leakage rate (ELR), malondialdehyde (MDA), proline, soluble sugar, and organic acids were also measured. The results showed that S. alterniflora mainly accumulated Cu in fine roots. No significant changes of biomass of fine roots were detected except for obvious reduction under 1,000 mg kg⁻¹ Cu. In leaves, rhizomes and fine roots, the highest Cu accumulations were detected under 800 mg kg⁻¹ Cu. The highest Cu accumulation in stem was revealed under 200 mg kg⁻¹ Cu. Plant height decreased under 1,000 mg kg⁻¹ Cu; chlorophyll content reduced under >50 mg kg⁻¹ Cu; levels of ELR and MDA increased under >200 mg kg⁻¹ Cu. However, osmotic components such as proline and soluble sugar were accumulated to cope with higher Cu stresses (800 and 1,000 mg kg⁻¹ ). Further, oxalic and citric acids were positively related with Cu contents in leaves and stems, suggesting that oxalic and citric acids may be related to Cu detoxification in aboveground parts of S. alterniflora. However, in above and belowground parts, no detoxification function of ascorbic and fumaric acids was observed due to unchanged or decreased trend under Cu stress.
12

The spatial-temporal pattern and source apportionment of water pollution in a trans-urban river

61%
Zhang Q., Wang X., Wan W., Hou P., Li R., Ouyang Z.
Polish Journal of Environmental Studies
|
2015
|
tom 24
|
nr 2
Deteriorating water quality in urban areas has drawn wide interest in China. In our study, water quality was monitored monthly during December 2009-November 2011 from 16 sites located in a trans-urban river. The spatial pattern showed that the concentrations of EC, Ca²⁺, Mg²⁺, BOD₅, CODcr, TP, and NH₄⁺-N were higher midstream and downstream than upstream, while measured pH and DO upstream were higher than measurements midstream and downstream. The temporal pattern showed that the concentrations of EC, TP, BOD₅, NH₄⁺-N, Mg²⁺, and Ca²⁺ in the wet season were lower than in the dry season, while the concentrations of CODcr in the wet season were higher than in the dry season. Receptor-based source apportionment revealed that most of the variables were influenced by domestic sewage, cropland, and woodland runoff pollution. Therefore, the best method to prevent water quality degradation is to manage the domestic sewage, cropland, and woodland runoff.
13

Effects of organic mulch on soil moisture and nutrients in karst area of Southwest China

61%
Li R., Li Q., Zhang J., Liu Z., Pan L., Huang K., Zhang L.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 6
14
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Enhancement of the stabilities and intracellular antioxidant activities of lavender essential oil by metal-organic frameworks based on beta-cyclodextrin and potassium cation

61%
Wang Y., Wang L., Tan J., Li R., Jiang Z.-T., Tang S.-H.
Polish Journal of Food and Nutrition Sciences
|
2021
|
tom 71
|
nr 1
Lavender (Lavandula angustifolia) is an important medicinal and aromatic plant. However, the application of lavender essential oil (LEO) is limited by its instability, low solubility and high volatility. Therefore, to improve the stabilities and antioxidant activities of LEO and thereby expand the applications, LEO was microencapsulated by metal-organic frameworks based on β-cyclodextrin and potassium cation (K-βCD-MOFs) with different mass core/wall ratios. The results showed that the best inclusion rate was 96.67% with the ratio of 1:10. Then, the optimum inclusion product was characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). The thermal and pH stabilities and the intracellular antioxidant activities were also studied. The results showed that the stabilities of the oil with K-βCD-MOFs inclusions and their abilities to resist acid and alkali were significantly stronger than those of LEO itself. In addition, the intracellular antioxidant activities of LEO were also enhanced by the K-βCD-MOFs inclusion. These results suggested the potential of K-βCD-MOFs as carriers for essential oils in food industry applications.
15
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Expression analysis of multifunctional RNA-binding protein hnRNP K during development of mammalian testis

61%
Xu H., Zhang P., Li R., Wu W., Wang S., Xu Y.
Polish Journal of Veterinary Sciences
|
2018
|
tom 21
|
nr 2
16

Effects of exogenous Fibroblast Growth Factor-21 on characteristic parameters related to energy metabolism in dairy cows

61%
Chen Y., Wu Q., Gao Y., Zhang H., Dong Z., Li R., Xu C.
Medycyna Weterynaryjna
|
2019
|
tom 75
|
nr 12
Negative energy balance (NEB) is a common pathological foundation of fatty liver and ketosis. Liver and fat tissue are the major organs of lipid metabolism, which is also a key metabolic pathway that regulates NEB development during the perinatal period. Fibroblast growth factor-21 (FGF-21) is a protein hormone that plays an important role in adipose lipid metabolism and liver gluconeogenesis. Our aim was to investigate the effects of exogenous FGF-21 on characteristic parameters related to energy balance in dairy cows. Ten non-pregnant, non-lactating Holstein-Friesian dairy cows were randomly allocated into two groups. The interventions were exogenous FGF-21 injection group received 1 ug/kg BW (body weight) of recombinant bovine FGF-21 by intravenous injection, and control group received physiological saline injections by intravenous injection. In comparison to saline injections, intravenous injections of FGF-21 either increased or tended to increase concentrations of FGF-21 (p < 0.05), BHBA (p < 0.05), adiponectin, leptin and HDL-C. FGF-21 injections decreased or tended to decrease concentrations of insulin, glucose, glucagon (p < 0.05), ALT/GPT (p < 0.05), AST/GOT (p < 0.05), urate, creatinine (p < 0.05), BUN, triglyceride (p < 0.05), T-CHO and LDL-C (p < 0.05). The results indicate that FGF-21 has only negative effects on the metabolites and metabolic hormones related to NEB in serum of dairy cows, but it has more beneficial effects on prominent adipokines, liver function index, renal function index, lipoprotein profiles related to the pathological changes that occurred in NEB.
17

Effects of saline-alkaline stress on early growth strategy and colonization success of Flaveria bidentis ( L.) Kuntze (Asteraceae ) - a new exotic plant in Northern China

61%
Chai M., Shi F., He K. S., Li R., Cao D., He Z.
Polish Journal of Ecology
|
2012
|
tom 60
|
nr 3
Flaveria bidentis, an annual grass native to South America, has invaded into many countries all over the world, including South Africa and Egypt in Africa, Britain and France in Europe, Japan in Asia, and Australia. In China, this plant species has been widely distributed in Hebei province since 2001 of its first discovery in Tianjin. In salinized soil of northern China, F. bidentis has formed mono dominant communities owing to its opportunistic characteristics. In this study, we investigated germination rate, germination energy, germination index and vigor index in response to different saline-alkaline stresses. Lengths of seedling, hypocotyl, and radicle were also examined. During germination process, germination rate, germination energy, germination index, and vigor index decreased due to higher salinity and alkalinity (pH). Hypocotyl elongation was stimulated at low salinity and alkalinity, but decreased with increasing salinity and alkalinity. The lengths of radicle and seedling were inhibited sharply with increasing salinity and alkalinity. These results suggest that a reciprocal enhancement between salt stress and alkaline stress was a characteristic feature during seed germination of F. bidentis. Ungerminated seeds resumed to germinate after transferred to distilled water, indicating that seeds remained viable during their exposure to saline-alkaline stresses. Stepwise regression analysis indicated that the effects of salinity, alkalinity (pH), and buffer capacity on seed germination and seedling growth were significantly different in magnitude. Salinity and alkalinity (pH) were the dominant factors in seed germination and seedling growth of F. bidentis respectively. burther, the results of this study suggest that F. bidentis has developed excellent adaptative strategy in its early stage of life cycle which partially explains its current invasion success in northern China.
18

Effects of low nitrogen and drought stresses on proline synthesis of Jatropha curcas seedling

61%
Wang W. G., Li R., Liu B., Li L., Wang S. H., Chen F.
Acta Physiologiae Plantarum
|
2011
|
tom 33
|
nr 5
Proline is one of the most important osmoregulatory solutes subjected to osmotic stresses. In this study, low nitrogen supply suppressed the dry biomass, leaf area, and proline biosynthesis of the seedlings of the energy plant Jatropha curcas, which could grow in poor, dry soil. Low-nitrogen stress induced JcP5CS mRNA expression and decreased the activity of P5CS enzyme and the content of free proline in leaves of J. curcas seedlings. When the seedlings grown in low-nitrogen conditions were suddenly exposed to PEG-6000 (-1.6 MPa) stress, the expression of JcP5CS gene was highly induced, and both the activity of P5CS and the content of free proline increased and maintained at high levels to mitigate the impact of drought stresses. This may be one of the reasons why J. curcas could adapt to poor and drought conditions.
19

Effects of ultrasound on vascular endothelial growth factor in cartilage, synovial fluid, and synovium in rabbit knee osteoarthritis

61%
Luo Q., Fan S., Li R., Ouyang Z., Liu Z., Lin Q.
Acta Biochimica Polonica
|
2020
|
tom 67
|
nr 3
20

The novel Na+/H+ antiporter gene SpNHX1 from Sesuvium portulacastrum confers enhanced salt tolerance to transgenic yeast

52%
Zhou Y., Yang C., Hu Y., Yin X., Li R., Fu S., Zhu B., Guo J., Jiang X.
Acta Physiologiae Plantarum
|
2018
|
tom 40
|
nr 03
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