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Very low calorie ketogenic diet and common rheumatic disorders:A case report
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作者 Mariangela Rondanelli Zaira Patelli +7 位作者 Clara Gasparri Francesca Mansueto Cinzia Ferraris Mara Nichetti Tariq A Alalwan Ignacio Sajoux Roberto Maugeri Simone Perna 《World Journal of Clinical Cases》 SCIE 2023年第9期1985-1991,共7页
BACKGROUND The scientific literature provides evidence that nutritional ketosis can be an important support in the treatment of pathologies in which inflammation is present,as recent studies have shown that ketone bod... BACKGROUND The scientific literature provides evidence that nutritional ketosis can be an important support in the treatment of pathologies in which inflammation is present,as recent studies have shown that ketone bodies have anti-inflammatory activity in numerous diseases,including rheumatic diseases.We report the case of a 22-year-old woman with class I obesity and juvenile idiopathic arthritis who started treatment with a very low calorie ketogenic diet(VLCKD).CASE SUMMARY The patient was a 22-year-old woman diagnosed with juvenile idiopathic arthritis at age 4 years and with a body mass index(BMI)of 30.8 kg/m2,waist circumference(WC)80 cm,fat mass(FM)28.1 kg,free FM 45.7 kg,and visceral adipose tissue(VAT)3.5 kg,assessed on bioimpedance analysis.She was treated using a commercial VLCKD weight-loss program(PNK®method);this program provides high-biological-value protein preparations and natural foods.Each protein preparation contains 15 g protein,4 g carbohydrate,3 g fat,and 50 mg omega-3 docosahexaenoic acid,with an energy content of 90–120 kcal.After four months on the program,the BMI was 28.6 kg/m2,WC 73 cm,FM 23.2 kg,free FM 41.9 kg,and VAT 2.9 kg.CONCLUSION VLCKD enabled the patient to reach her target weight and to reduce her joint pain and headaches.Laboratory inflammatory indices also normalized. 展开更多
关键词 Very low calorie ketogenic diet INFLAMMATION PNK
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Enhanced nitrogen removal at low temperature with mixed anoxic/oxic process
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作者 Xiang-kun Li Ying-jun Yang +2 位作者 Gai-ge Liu Dou-dou Sun Xiao-chen Ma 《Water Science and Engineering》 EI CAS CSCD 2023年第1期67-75,共9页
Different hydraulic retention times(HRTs)were tested in a mixed anoxic/oxic(A/O)system at 5C and 10C to investigate the effects of HRT and carrier on nitrogen removal in wastewater at low temperatures.The results show... Different hydraulic retention times(HRTs)were tested in a mixed anoxic/oxic(A/O)system at 5C and 10C to investigate the effects of HRT and carrier on nitrogen removal in wastewater at low temperatures.The results showed that the addition of the fillers improved the treatment effect of each index in the system.With an optimal HRT of 7.5 h at 5C,the removal efficiencies of NHþ4-N and total nitrogen(TN)reached 91.2%and 75.6%,respectively.With an HRT of 6 h at 10C,the removal efficiencies of NHþ4-N and TN were 96.7%and 82.9%,respectively.The results of high-throughput sequencing showed that the addition of the suspended carriers in the aerobic zone could improve the treatment efficiency of nitrogen at low temperatures.The microbial analysis indicated that the addition of the suspended carriers enhanced the enrichment of nitrogen removal bacteria.Nitrospira,Nitrotoga,and Nitrosomonas were found to be the bacteria responsible for nitrification,and their relative concentrations on the biofilm at 5C and 10C accounted for 98.11%,92.79%,and 69.98%of all biological samples,respectively. 展开更多
关键词 Domestic sewage low temperature Mixed A/O process nitrogen removal Bacterial community structure
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Pilot Test for Nitrogen Foam Flooding in Low Permeability Reservoir
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作者 Xinyu Zhou Jia Huang +5 位作者 Yuchen Qian Wenli Luo Lisha Qi Jie Wang Zhibin Jiang Hao Kang 《Energy Engineering》 EI 2023年第3期763-774,共12页
Due to the characteristics of reservoir formation,the producing level of low permeability reservoir is relatively very low.It is hard to obtain high recovery through conventional development schemes.Considering the ti... Due to the characteristics of reservoir formation,the producing level of low permeability reservoir is relatively very low.It is hard to obtain high recovery through conventional development schemes.Considering the tight matrix,complex fracture system,low production level of producers,and low recovery factor ofMblock in Xinjiang oilfield,it is selected for on-site pilot test of nitrogen foam flooding.Detailed flooding scheme is made and the test results are evaluated respectively both for producers and injectors.The pressure index,filling degree,and fluid injection profile are found to be all improved in injectors after injection of nitrogen foam.The oil production,water cut and liquid production file are also improved in most of the producers,with the natural decline rate in the test area become slow.Results show that nitrogen foam flooding technology can be good technical storage for enhanced oil recovery in low permeability reservoir. 展开更多
关键词 Fluid production profile nitrogen foam low permeability pilot test
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Chemical, Nutritional and Organoleptical Characteristics of Orange-Based Formulated Low-Calorie Jams 被引量:1
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作者 Rafeek M. Abolila Hassan Barakat +1 位作者 Hassan A. El-Tanahy Hamdy A. El-Mansy 《Food and Nutrition Sciences》 2015年第13期1229-1244,共16页
Twelve low-calorie orange-based formulated jams were prepared mainly from orange, pumpkin and papaya, and then sweetened using fructose (F), stevioside (St) and sucralose (Su). The nutritional value of formulated jams... Twelve low-calorie orange-based formulated jams were prepared mainly from orange, pumpkin and papaya, and then sweetened using fructose (F), stevioside (St) and sucralose (Su). The nutritional value of formulated jams was estimated after the approximate chemical composition and total soluble solid have been determined. The effect of storage on total phenolic compounds, antioxidant capacity, carotenoids content and vitamin C was investigated. Organoleptical attributes of prepared low-calorie jams were done as well. Results indicated that the nutritive value [kcal 100 g–1 fw] ranged from 88.10 ± 0.60 to 164.34 ± 0.41;total phenol content (TPC, mg GAE 100 g–1 fw] ranged from 188.52 ± 2.45 to 411.79 ± 3.3;the antioxidant capacity (μmol TE g–1 fw) ranged from 14.57 ± 0.86 to 32.39 ± 1.19;total carotenoids [mg 100 g–1 fw] ranged from 115.20 ± 5.66 to 204.33 ± 4.21;vitamin C [mg 100 g fw] ranged from 8.94 ± 1.07 to 28.77 ± 4.46;total soluble solids [Brix] ranged from 22.53 ± 0.05 to 43.37 ± 0.13. Jams storage for a period of 12 months at room temperature led to a decrease in vitamin C content, TPC, antioxidant capacity, while total soluble solids (TSS) and carotenoids increased during storage. The results of organoleptical attributes showed that the formulas O11, O1 had the highest score of color and odor respectively while O7 recorded maximum score for taste, texture and bitterness respectively. Statistical analysis showed that storage intervals and treatments had a significant (p < 0.05) effect on sensory quality of diet jam. The organoleptical characteristics were affected with the extension of shelf-life. Addition of stevioside and sucralose to formulate the low-calorie jam increased total phenol and antioxidant capacity, improved color, taste and produced targeted low-calorie jams. The use of sweeteners such as fructose, sucralose and stevioside in the manufacture of orange diet jam was shown to be satisfactory, resulting in low-calorie jams, improved the quality and could be produced commercially. 展开更多
关键词 low-calorie Jam CHEMICAL NUTRITIONAL Organoleptical CHARACTERISTICS
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Nutritional, Chemical and Organoleptical Characteristics of Low-Calorie Fruit Nectars Incorporating Stevioside as a Natural Sweetener 被引量:1
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作者 Hassan Barakat Abdulaziz Al-Furaydi +1 位作者 Abdulelah Al-Harbi Ali Al-Shedookhi 《Food and Nutrition Sciences》 2017年第1期126-140,共15页
The study is aiming at preparation of low-calorie fruit nectars for diabetes and weight maintaining approaches as well as consumer satisfaction. Therefore, twenty low-calorie fruit-based formulated nectars were prepar... The study is aiming at preparation of low-calorie fruit nectars for diabetes and weight maintaining approaches as well as consumer satisfaction. Therefore, twenty low-calorie fruit-based formulated nectars were prepared mainly from orange, pomegranate, guava and mango pulps which sweetened with sucrose or sucrose— replaced at 25%, 50%, 75% and 100% using stevioside. Primitively, the yield of fresh fruits had been calculated. Consequently, nutritional, chemical and organoleptical characteristics of prepared fruit nectars have been determined. Results indicated that total solids content was in range of 5.57% - 13.20%, 9.90% - 14.37%, 8.25% - 13.27% and 8.25% - 16.50% for orange, pomegranate, guava and mango nectars, respectively. Dependently, caloric value resulted 21.57 to 51.08, 38.31 to 55.62, 31.93 to 51.37 and 31.93 to 63.86 kcal 100 g-1 fw for orange, pomegranate, guava and mango nectars, respectively. Total phenols content [TPC, mg GAE 100 g-1 dw] ranged from 665.12 to 747.41, 1180.42 to 1319.47, 742.54 to 848.27 and 418.01 to 472.42 for orange, pomegranate, guava and mango nectars, respectively. The antioxidant capacity by DPPH method [μmol TE g-1 dw] ranged from (20.79 to 26.51), (47.13 to 56.56), (60.68 to 69.25) and (8.39 to 13.32) for orange, pomegranate, guava and mango nectars, respectively. Total carotenoids [mg 100 g-1 dw] were the highest in mango nectars ranged from (102.99 to 110.52) in mango nectar with 100% sugar and mango nectar with 100% stevioside, respectively. Anthocyanins content recorded 6.14 mg 100 g-1 dw in pomegranate nectar with 100% sugar, while increased to be 9.01 mg 00 g-1 dw in pomegranate nectar with 100% stevioside. Ascorbic acid [mg 100 g fw] ranged from 23.41 to 27.53, 15.73 to 18.32, 25.72 to 30.87 and 18.07 to 20.98 for orange, pomegranate, guava and mango nectars, respectively. The results of organoleptical attributes showed no effect of sugar substituting by stevioside on color, odor and mouth feel. The most dramatic effect of sugar substituting had been observed on taste, bitter after taste and the overall acceptability of prepared nectars with high substitution levels. Practically, using stevioside to produce low-calorie nectars was shown to be satisfactory up to 50% - 75% substituting level, resulting low-calorie nectars and could be applied commercially. 展开更多
关键词 low-calorie Nectar CHEMICAL NUTRITIONAL Organoleptical CHARACTERISTICS
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In vitro Anthocyanin Induction and Metabolite Analysis in Malus spectabilis Leaves Under Low Nitrogen Conditions 被引量:16
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作者 Jiaxin Meng Yan Gao +4 位作者 Meiling Han Pengyuan Liu Chen Yang Ting Shen Houhua Li 《Horticultural Plant Journal》 SCIE 2020年第5期284-292,共9页
Anthocyanins are the most widely produced secondary metabolites in plants,and they play an important role in plant growth and reproduction.The nitrogen source is an important factor affecting anthocyanin production,bu... Anthocyanins are the most widely produced secondary metabolites in plants,and they play an important role in plant growth and reproduction.The nitrogen source is an important factor affecting anthocyanin production,but the nitrogen concentrations on metabolism and the underlying genetic basis remain unclear.In this study,in vitro anthocyanin induction was conducted on Malus spectabilis.The leaf explants were cultivated in media containing different nitrogen concentrations.The results suggested that when the nitrogen contents decreased in limit,the color of leaf explants turned from green to red,and increased anthocyanin accumulation led to a change in phenotype.Furthermore,the content of other flavonoids,such as dihydroquercetin,epicatechin,and catechin,increased under low nitrogen conditions.The transcription levels of the general flavonoid pathway genes,from phenylalanine ammonia lyase(PAL)to anthocyanidin synthase(ANS),were associated with the concentration of corresponding flavonoid compounds and phenotype changes.In particular,the expression level of ANS increased substantially under a low nitrogen treatment,which was significantly and positively correlated with the anthocyanin levels(R2=0.72,P<0.05).The increased expression patterns of anthocyanin pathway genes were similar to that of the transcription factor MYB10.We further verified MYB10 played an important role in the anthocyanin pathway in leaves of Malus spectabilis.These results suggested that we can improve the desirable ornamental plant phenotypes by controlling nitrogen content.This process may offer clues to further development of new agricultural practices. 展开更多
关键词 CRABAPPLE PIGMENT flavonoid in vitro low nitrogen stress
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Growth traits and nitrogen assimilation-associated physiological parameters of wheat(Triticum aestivum L.) under low and high N conditions 被引量:6
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作者 ZHANG Fei-fei GAO Si +3 位作者 ZHAO Yuan-yuan ZHAO Xiao-lei LIU Xiao-man XIAO Kai 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第7期1295-1308,共14页
In this study, 14 wheat cultivars with contrasting yield and N use efficiency (NUE) were used to investigate the agronomic and NUE-related traits, and the N assimilation-associated enzyme activities under low and hi... In this study, 14 wheat cultivars with contrasting yield and N use efficiency (NUE) were used to investigate the agronomic and NUE-related traits, and the N assimilation-associated enzyme activities under low and high N conditions. Under deficient-N, the cultivars with high N uptake efficiency (UpE) and high N utilization efficiency (UtE) exhibited higher plant biomass, yields, and N contents than those with medium and low NUEs. The high UpE cultivars accumulated more N than other NUE type cultivars. Under sufficient-N, the tested cultivars showed similar patterns in biomass, yield, and N content to those under deficient-N, but the varietal variations in above traits were smaller. In addition, the high UpE cultivars displayed much more of root biomass and larger of root length, surface area, and volume than other NUE type cultivars, indicating that the root morphological traits under N deprivation are closely associated with the plant biomass through its improvement of the N acquisition. The high UtE cultivars showed higher activities of nitrate reductase (NR), nitrite reductase (NIR), and gluta- mine synthetase (GS) at stages of seediling, heading and filling than other NUE type cultivars under both low and high N conditions. Moreover, the high UpE and UtE cultivars also displayed higher photosynthetic rate under deficient-N than the medium and low NUE cultivars. Together, our results indicated that the tested wheat cultivars possess dramatically genetic variations in biomass, yield, and NUE. The root morphological traits and the N assimilation enzymatic acitivities play critical roles in regulating N accumulation and internal N translocation under the N-starvation stress, respectively. They can be used as morphological and biochemical references for evaluation of UpE and UtE in wheat. 展开更多
关键词 wheat (Triticum aestivum L.) low and high N biomass yield nitrogen use efficiency root morphological traits N assimilzation-associated enzyme photosynthetic rate
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Altered Expression of Transcription Factor Genes in Rice Flag Leaf under Low Nitrogen Stress 被引量:4
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作者 ZHAO Ming-hui ZHANG Wen-zhong +4 位作者 MA Dian-rong Xu Zheng-jin WANG Jia-yu ZHANG Li CHEN Wen-fu 《Rice science》 2012年第2期100-107,共8页
The response of transcription factor genes to low nitrogen stress was studied to provide molecular basis for improving the absorption and utilization efficiency of nitrogen fertilizer in rice. The agilent rice genome ... The response of transcription factor genes to low nitrogen stress was studied to provide molecular basis for improving the absorption and utilization efficiency of nitrogen fertilizer in rice. The agilent rice genome arrays were used to study the varied expression of transcription factor genes in two rice varieties (SN 196 and Toyonishhiki) with different chlorophyll contents under low nitrogen stress. The results showed that a total of 53 transcription factor genes (35 down-regulated and 18 up-regulated genes at the transcription level) in flag leaves of super-green rice SN196 and 27 transcription factor genes (21 down-regulated and 6 up-regulated genes at the transcription level) in flag leaves of Toyonishiki were affected by low nitrogen stress. Among those nitrogen-responsive genes, 48 transcription factor genes in SN196 and 22 in Toyonishiki were variety-specific. There were overlapped transcription factor genes responded to low nitrogen stress between SN196 and Toyonishiki, with 1 up-regulated and 4 down-regulated at the transcription level. Distributions of low nitrogen responsive genes on chromosomes were different in two rice varieties. 展开更多
关键词 RICE flag leaf MICROARRAY real-time quantitative PCR transcription factor low nitrogen stress
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Simultaneous nitrogen and phosphorus removal under low dissolved oxygen conditions 被引量:3
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作者 XIA Si-qing GAO Ting-yao ZHOU Zeng-yuan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第1期46-50,共5页
A full-scale test was operated by using low dissolved oxygen activated sludge process to enhance biological nitrogen and phosphorus removal. When the influent concentrations of CODCr, TN and TP varied in a range of 35... A full-scale test was operated by using low dissolved oxygen activated sludge process to enhance biological nitrogen and phosphorus removal. When the influent concentrations of CODCr, TN and TP varied in a range of 352.9 mg/L-1338.2 mg/L, 34.4 mg/L-96.3 mg/L, and 2.21 mg/L-24.0 mg/L, the average removal efficiencies were 94.9%, 86.7% and 93.0%, respectively. During the test period of two months, effluent meas of CODCr,, BOD5, NH3-N, TN and TP were below 50 mg/L, 25 mg/L, 10 mg/L and 1.0 mg/L respectively. The low dissolved oxygen activated sludge process has a simple flow sheet, fewer facilities and high N and P removal efficiency. It is very convenient to retrofit the conventional activated sludge process with the above process. 展开更多
关键词 high concentration activated sludge low dissolved oxygen process nitrogen removal phosphorus removal
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Comparative analysis of metabolite changes in two contrasting rice genotypes in response to low-nitrogen stress 被引量:3
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作者 Xiuqin Zhao Wensheng Wang +6 位作者 Ziyan Xie Yongming Gao Chunchao Wang Muhammed Mahbubur Rashid Mohammad Rafiqul Islam Binying Fu Zhikang Li 《The Crop Journal》 SCIE CAS CSCD 2018年第5期464-474,共11页
Identification of metabolites responsible for tolerance to low nitrogen availability(low-N)will aid in the genetic improvement of rice yield under nitrogen deficiency.In this study,a backcross introgression line(G9)an... Identification of metabolites responsible for tolerance to low nitrogen availability(low-N)will aid in the genetic improvement of rice yield under nitrogen deficiency.In this study,a backcross introgression line(G9)and its recurrent parent Shuhui 527(SH527),which show differential responses to low-N stress,were used to identify metabolites associated with lowN tolerance in rice.Differences in metabolite contents in the leaves of G9 and SH527 at three growth stages under low-N stress were assessed by gas chromatography–mass spectrometry.Many metabolites,including amino acids and derivatives,were highly enriched in G9 compared with SH527 under the control condition,suggesting that the two genotypes had basal metabolite differences.Low-N stress induced genotype-specific as well as growth stagedependent metabolite changes.Metabolites induced specifically in G9 that were involved in glycolysis and tricarboxylic acid metabolism were enriched at the tillering and grain filling stages,and metabolites involved in nitrogen and proline metabolism were enriched at the booting stage.Enrichment of pyroglutamate,glutamate,2-oxoglutarate,sorbose,glycerate-2-P,and phosphoenolpyruvic acid in G9 suggests that these metabolites could be involved in low-N stress tolerance.The results presented here provide valuable information for further elucidation of the molecular mechanisms of low-N tolerance in crops. 展开更多
关键词 low-N stress low-N TOLERANCE
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Charactering protein fraction concentrations as influenced by nitrogen application in low-glutelin rice cultivars 被引量:11
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作者 LI Gang-hua CHEN Yi-lu +5 位作者 DING Yan-feng GENG Chun-miao LI Quan LIU Zheng-hui WANG Shao-hua TANG She 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第3期537-544,共8页
To optimize both grain yield and quality of low-glutelin rice cultivars under N-fertilizer strategies, two-year field experiments involving three low-glutelin rice cultivars(W1240, W1721, W025) and an ordinary rice ... To optimize both grain yield and quality of low-glutelin rice cultivars under N-fertilizer strategies, two-year field experiments involving three low-glutelin rice cultivars(W1240, W1721, W025) and an ordinary rice cultivar(H9405) with five N treatments were carried out to determine the effects of N application rate and genotype on protein fractions contents and Glutelin/Prolamin ratio(Glu/Pro). The difference of protein fraction concentrations affected by N application rate existed in genotypes. Ordinary rice cultivar had a larger increase in glutlein concentration affected by N application rate than low-glutelin rice cultivars did. Glutelin in H9405 had a increase of 30.6 and 41.0% under the N4 treatment(360 kg N ha^(–1)) when compared with N0 treatment(no fertilizer N) in 2010 and 2011 respectively, while all the low-glutelin rice cultivars showed relatively smaller increases for two years. Variance analysis showed no significant effect of N application rate on glutelin in W1240 and W025 while the effects on albumin, globulin and prolamin were significant in low-glutelin rice. What's more, N treatment had no significant i nfluence on Glu/Pro ratios in low-glutelin rice cultivars while a significant increase in Glu/Pro ratio was observed in ordinary rice cultivar. So low-gultelin rice cultivars showed a different pattern from ordinary rice cultivars when influenced by N application rate. 展开更多
关键词 low-glutelin rice nitrogen protein fractions Glu/Pro
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Nitrogen removal for low-carbon wastewater in reversed A^2/O process by regulation technology 被引量:1
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作者 张智 陈杰云 +3 位作者 谢丽华 范功端 尹晓静 李勇 《Journal of Central South University》 SCIE EI CAS 2009年第S1期304-308,共5页
Full scale experimental study on nitrogen removal for low-carbon wastewater was conducted in reversed A2/O process in Jiguanshi waste water treatment plant in Chongqing,in order to aid the operation and maintenance of... Full scale experimental study on nitrogen removal for low-carbon wastewater was conducted in reversed A2/O process in Jiguanshi waste water treatment plant in Chongqing,in order to aid the operation and maintenance of similar WWTP. When the proposed measures,such as using 0.1% (volume fraction of wastewater) landfill leachate,shortening HRT by 2/3 in the primary sedimentation tank and controlling DO at 0.5 mg/L in the 3rd section of aerobic zone,are applied,15% of the carbon source can be complemented,the favorable property of activated sludge is achieved,and the nitrogen removal effect is significantly improved. The effluent NH3-N is 2 mg/L and the removal rate is 90%. The effluent TN is 17 mg/L and the removal rate is 54%. The up-to-standard discharge of the effluent is achieved. And after the optimization,the unit electricity consumption also reaches 0.21 kW/h and saves 20%. 展开更多
关键词 reversed A2/O process low-carbon resource LANDFILL LEACHATE primary SEDIMENTATION TANK nitrogen removal
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Cloning and Expression Analysis of Sucrose Non-fermenting-1 Related Protein Kinase (SnRK) in Cucumis sativus L. Under Low Nitrogen Conditions
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作者 He Hong-mei Qin Zhi-wei +1 位作者 Feng Zhuo Wu Tao 《Journal of Northeast Agricultural University(English Edition)》 CAS 2013年第4期1-9,共9页
The sucrose non-fermenting-1 related protein kinase(SnRK), whose expression is induced by kinds of hyperosmotic stresses, plays a key role in improving stress resistance of plants. In order to investigate the molecu... The sucrose non-fermenting-1 related protein kinase(SnRK), whose expression is induced by kinds of hyperosmotic stresses, plays a key role in improving stress resistance of plants. In order to investigate the molecular mechanism of low nitrogen resistance in cucumber, the full-length cDNA of SnRK gene was cloned in this study. The result showed that SnRK gene was 1 548 bp in length, encoded 515 amino acids, and had more than 80% homology with other crops. The protein encoded by this gene was an unstable and hydrophilic protein with no transmembrane structure and no signal peptide. Under nitrogen-free conditions and low nitrogen conditions, the expression pattern analysis of SnRK gene showed that this gene was up-regulated and its expression increased and was significantly higher than the normal level as the nitrogen concentration decreased. In addition, the expression of SnRK gene was also inhibited in the high nitrogen level and was significantly lower than the normal level. The result of this study would help us understand the molecular mechanism of low nitrogen resistance in cucumber. 展开更多
关键词 CUCUMBER SnRK gene CLONE expression analysis low nitrogen
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Effect of Low Nitrogen Stress on IAA Metabolome of Tall Fescue
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作者 Li Xiaodong Wang Xiaoli +3 位作者 Sun Fang Chen Guangji Wu Jiahai Cai Yiming 《Animal Husbandry and Feed Science》 CAS 2017年第1期53-59,共7页
Forages generally suffer more severe nutrition stress than other crops, but the corresponding theoretical studies still lag behind. In this study, metabo- lites in tall fescue leaves under normal and low nitrogen cond... Forages generally suffer more severe nutrition stress than other crops, but the corresponding theoretical studies still lag behind. In this study, metabo- lites in tall fescue leaves under normal and low nitrogen conditions were analyzed with LC-ESI-MS ( liquid chromatography-electrospray ionization-mass spectrome- try). A total of 1 424 and 1 251 metabolites were detected from two groups of samples respectively using OPLS-DA (orthogonal partial least squares discriminant analysis). The content of 13 major metabolites changed under low nitrogen stress, including auxin (indale acetic acid, IAA). Quantitative real-time PCR (qRT- PCR) showed that eight genes related to IAA signaling pathway were up-regulated after nitrogen stress. Enzyme-linked immuno sorbent assay (ELISA) revealed that the IAA concentration was elevated in tall fescue leaves after nitrogen stress. Our research provides valuable information for studying the response mechanisms of tall feseue to low nitrogen. The results suggest that application of IAA could be used to alleviate the harmful effects of nitrogen deficiency. 展开更多
关键词 Tall fescue low nitrogen treatment METABOLOME IAA
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Producing ultra-high-speed nitrogen jets by arc heating in a low-pressure chamber
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作者 Wenxia Pan Xian Meng +1 位作者 Heji Huang Chengkang Wu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2016年第1期60-63,共4页
Pure nitrogen gas was heated with direct current arc, at input powers from several hundred Watt to over 5 kW, and then injected through a nozzle into a chamber at 1 or 10 Pa pressure, with the purpose of accelerating ... Pure nitrogen gas was heated with direct current arc, at input powers from several hundred Watt to over 5 kW, and then injected through a nozzle into a chamber at 1 or 10 Pa pressure, with the purpose of accelerating the gas to very high speed around 7 km/s. Various structures of the arc generator and gas expansion nozzle were examined. Results show that bypass exhausting of the boundary layer before it enters the nozzle divergent section can greatly increase flow speed of the jet, thus it might be possible to use nitrogen as a working gas in high speed gas dynamic test facilities. 展开更多
关键词 low-power nitrogen arc-heater Lateral bypass-exhausting Very high flow speed Nozzle structure Chamber pressure
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Advanced landfill leachate treatment using a two-stage UASB-SBR system at low temperature 被引量:26
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作者 Hongwei Sun,Qing Yang,Yongzhen Peng,Xiaoning Shi,Shuying Wang,Shujun Zhang Key Laboratory of Beijing Water Quality Science and Water Envirocnnment Recovery Engineering,Beijing University of Technology,Beijing 100124,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第4期481-485,共5页
A two-stage upflow anaerobic sludge blanket (UASB) and sequencing batch reactor (SBR) system was introduced to treat landfill leachate for advanced removal of COD and nitrogen at low temperature. In order to impro... A two-stage upflow anaerobic sludge blanket (UASB) and sequencing batch reactor (SBR) system was introduced to treat landfill leachate for advanced removal of COD and nitrogen at low temperature. In order to improve the total nitrogen (TN) removal efficiency and to reduce the COD requirement for denitrification, the raw leachate with recycled SBR nitrification supematant was pumped into the first-stage UASB (UASB1) to achieve simultaneous denitrification and methanogenesis. The results showed that UASB1 played an important role in COD removal and UASB2 and SBR further enhanced the nutrient removal efficiency. When the organic loading rates of UASB1, UASB2 and SBR were 11.95, 1.63 and 1.29 kg COD/(m^3.day), respectively, the total COD removal efficiency of the whole system reached 96.7%. The SBR acted as the real undertaker for NH4^+-N removal due to aerobic nitrification. The system obtained about 99.7% of NH4^+-N removal efficiency at relatively low temperature (14.9-10.9℃). More than 98.3% TN was removed through complete denitrification in UASB 1 and SBR. In addition, temperature had a significant effect on the rates of nitrification and denitrification rather than the removal of TN and NH4^+-N once the complete nitrification and denitrification were achieved. 展开更多
关键词 landfill leachate two-stage UASB-SBR advanced nitrogen removal low temperature NITRIFICATION DENITRIFICATION
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Effects of low temperature on sludge settleability and nutrients removal performance treating domestic wastewater 被引量:2
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作者 彭赵旭 彭永臻 +2 位作者 刘旭亮 于振波 柴同志 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第5期55-60,共6页
In order to investigate the effect of temperature on activated sludge systems,sludge settleability,nitrogen and phosphorus removal processes were investigated by changing temperature variation patterns using 4 sequenc... In order to investigate the effect of temperature on activated sludge systems,sludge settleability,nitrogen and phosphorus removal processes were investigated by changing temperature variation patterns using 4 sequencing batch reactors (SBR).The results showed that no matter temperature changes in the range of 15-22 ℃ (decrease or increase) gradually or sharply,it has little effect on nitrogen and phosphorus removal processes.But when temperature decreases to 12 ℃,biochemical reactions will be inhibitted obviously.At least 1 sludge retention time (SRT) is needed for nitrification adapt to new temperature envirionment,and more time is necessary for phosphorus removal process.When temperature increases from 12 ℃ to 22 ℃ sharply,nitrification process deteriorates seriously,but phosphorus removal process shows no change.In addition,sludge settleability deteriorates when temperature changes sharply (decrease or increase),but the reasons are different.Under temperature decrease condition,it is mainly caused by the increase of accumulated extracellular polymeric substances (EPS).Under temperature increase condition,the loosing sludge flocs' configuration is the main reason.It should be pointed out that the filamentous bacteria content during the entire experiment keeps almost constant,and the sludge settleability variations are the reflection of the change of sludge physicochemical characteristics. 展开更多
关键词 low temperature activated sludge SBR nitrogen and phosphorus removal sludge settleability
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Effect of various Na/K ratios in low-salinity well water on growth performance and physiological response of Pacific white shrimp Litopenaeus vannamei 被引量:1
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作者 刘泓宇 谭北平 +4 位作者 杨金芳 林颖博 迟淑艳 董晓慧 杨奇慧 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第5期991-999,共9页
To investigate the influence of sodium to potassium(Na/K) ratios on the growth performance and physiological response of the Pacific white shrimp( Litopenaeus vananmei), various concentrations of KCl were added to low... To investigate the influence of sodium to potassium(Na/K) ratios on the growth performance and physiological response of the Pacific white shrimp( Litopenaeus vananmei), various concentrations of KCl were added to low-salinity well water(salinity 4) in an 8-week culture trial. Six treatments with Na/K ratios of 60:1, 42:1, 33:1, 23:1, 17:1, and 14:1 were replicated in triplicate. The highest weight-gain rate(3 506±48)% and survival rate(89.38±0.88)% was observed in well water with Na/K ratios of 23:1 and 42:1, respectively, while the feed conversion ratio(1.02±0.01), oxygen consumption, and ammonia-N excretion rate was the lowest in the medium with a Na/K ratio of 23:1. Gill Na +-K +-ATPase activity, as an indicator of osmoregulation, peaked in the treatment where the Na/K ratio was 17:1. The total hemocyte count, respiratory burst, and immune-related enzyme activities(ALP, LSZ, PO, and SOD) of L. vananmei were affected significantly by Na/K ratios( P <0.05). After challenged with Vibrio harveyi, the cumulative mortality of shrimp reared in a Na/K ratio of 23:1(30±14.14)% was significantly lower than the control(75±7.07)%. In conclusion, the addition of K + to low-salinity well water in L. vannamei cultures is feasible. Na/K ratios ranging from 23:1 to 33:1 might improve survival and growth. Immunity and disease resistance are also closely related to the Na/K ratio of the low-salinity well water. The findings may contribute to the development of more efficient K + remediation strategies for L. vananmei culture in low-salinity well water. 展开更多
关键词 太平洋白对虾 低盐度水 南美白对虾 氯化钾 生理反应 生长性能 比值
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Surface Etching and DNA Damage Induced by Low-Energy Ion Irradiation in Yeast
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作者 刘雪兰 许安 +2 位作者 戴银 袁航 余增亮 《Plasma Science and Technology》 SCIE EI CAS CSCD 2011年第3期381-384,共4页
Bio-effects of survival and etching damage on cell surface and DNA strand breaks were investigated in the yeast saccharomyces cerevisiae after exposure by nitrogen ion with an energy below 40 keV. The result showed th... Bio-effects of survival and etching damage on cell surface and DNA strand breaks were investigated in the yeast saccharomyces cerevisiae after exposure by nitrogen ion with an energy below 40 keV. The result showed that 16% of trehalose provided definite protection for cells against vacuum stress compared with glycerol. In contrast to vacuum control, significant morpho- logical damage and DNA strand breaks were observed, in yeast cells bombarded with low-energy nitrogen, by scanning electron microscopy (SEM) and terminal deoxynucleotidyl transferase- mediated dUTP nick end labeling (TUNEL) immunofluorescence assays. Moreover, PI (propidium iodide) fluorescent staining indicated that cell integrity could be destroyed by ion irradiation. Cell damage eventually affected cell viability and free radicals were involved in cell damage as shown by DMSO (dimethyl sulfoxide) rescue experiment. Our primary experiments demonstrated that yeast cells can be used as an optional experimental model to study the biological effects of low energy ions and be applied to further investigate the mechanism(s) underlying the bio-effects of eukaryotic cells. 展开更多
关键词 low-energy nitrogen ions YEAST radiation model damage effects
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Development of Low Carbon Aquaculture System by Using Zeolite
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作者 Ashamol Antony Baskaran Manimaran 《Journal of Earth Science and Engineering》 2014年第5期295-310,共16页
关键词 养殖系统 沸石 阳离子交换容量 生化需氧量 化学需氧量 开发 低碳 离子交换介质
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