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Seasonal Variation of the Sea Surface Temperature Growth Rate of ENSO
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作者 Xinyi XING Xianghui FANG +1 位作者 Da PANG Chaopeng JI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期465-477,共13页
El Ni?o–Southern Oscillation(ENSO) exhibits a distinctive phase-locking characteristic, first expressed during its onset in boreal spring, developing during summer and autumn, reaching its peak towards winter, and de... El Ni?o–Southern Oscillation(ENSO) exhibits a distinctive phase-locking characteristic, first expressed during its onset in boreal spring, developing during summer and autumn, reaching its peak towards winter, and decaying over the next spring. Several studies have demonstrated that this feature arises as a result of seasonal variation in the growth rate of ENSO as expressed by the sea surface temperature(SST). The bias towards simulating the phase locking of ENSO by many state-of-the-art climate models is also attributed to the unrealistic depiction of the growth rate. In this study, the seasonal variation of SST growth rate in the Ni?o-3.4 region(5°S–5°N, 120°–170°W) is estimated in detail based on the mixed layer heat budget equation and recharge oscillator model during 1981–2020. It is suggested that the consideration of a variable mixed layer depth is essential to its diagnostic process. The estimated growth rate has a remarkable seasonal cycle with minimum rates occurring in spring and maximum rates evident in autumn. More specifically, the growth rate derived from the meridional advection(surface heat flux) is positive(negative) throughout the year. Vertical diffusion generally makes a negative contribution to the evolution of growth rate and the magnitude of vertical entrainment represents the smallest contributor. Analysis indicates that the zonal advective feedback is regulated by the meridional immigration of the intertropical convergence zone, which approaches its southernmost extent in February and progresses to its northernmost location in September, and dominates the seasonal variation of the SST growth rate. 展开更多
关键词 SST growth rate intertropical convergence zone zonal advective feedback mixed layer depth ENSO seasonal variation
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Quantifying the natural growth rate of hepatocellular carcinoma:A real-world retrospective study in southwestern China
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作者 Li Tu Hong Xie +6 位作者 Qi Li Ping-Gui Lei Pei-Ling Zhao Fan Yang Chi Gong Yuan-Lin Yao Shi Zhou 《World Journal of Hepatology》 2024年第5期800-808,共9页
BACKGROUND In recent years,approximately half of the newly diagnosed cases and mortalities attributed to hepatocellular carcinoma(HCC)have been reported in China.Despite the high incidence of HCC,there remains a pauci... BACKGROUND In recent years,approximately half of the newly diagnosed cases and mortalities attributed to hepatocellular carcinoma(HCC)have been reported in China.Despite the high incidence of HCC,there remains a paucity of data regarding the natural growth pattern and the determination of optimal surveillance intervals specific to the Chinese population.AIM To quantify the natural tumor growth pattern of HCC in regional China.METHODS A retrospective analysis was performed on patients from a single institution in Southwest China who had undergone two or more serial dynamic computed tomography or magnetic resonance imaging scans between 2014 and 2020,without having received any anti-cancer therapy.Tumor growth was assessed using tumor volume doubling time(TVDT)and tumor growth rate(TGR),with volumes measured manually by experienced radiologists.Simple univariate linear regression and descriptive analysis were applied to explore associations between growth rates and clinical factors.RESULTS This study identifies the median TVDT for HCC as 163.4 d,interquartile range(IQR)72.1 to 302.3 d,with a daily TGR of 0.42%(IQR 0.206%-0.97%).HCC growth patterns reveal that about one-third of tumors grow indolently with TVDT exceeding 270 d,another one-third of tumors exhibit rapid growth with TVDT under 90 d,and the remaining tumors show intermediate growth rates,with TVDT ranging between 3 to 9 months.CONCLUSION The identified TGRs support biannual surveillance and follow-up for HCC patients in certain regions of China.Given the observed heterogeneity in HCC growth,further investigation is warranted. 展开更多
关键词 Hepatocellular carcinoma Natural tumor growth pattern Tumor volume doubling time Tumor growth rate Realworld retrospective study
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Evaluation of Growth Rate of Invasive Aquatic Macrophytes and Contribution to Its Use in Organic Fertilizer Production: A Case of Eicchornia crassipes (Mart.) Solms, 1883 in the Lobé Creek (Littoral-Cameroon)
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作者 Roland Didier Nwamo Gordon Nwutih Ajonina +2 位作者 Tapite Chanel Yamkou Kopmou Thomas Efole Ewoukem Minette Tomedi Eyango 《Open Journal of Ecology》 2024年第7期571-583,共13页
From 20 January to 20 July 2023, a study was carried out on the Lobé Creek, a waterway subject to considerable natural and man-made pressures, with a negative impact on its biodiversity and habitats. The aim was ... From 20 January to 20 July 2023, a study was carried out on the Lobé Creek, a waterway subject to considerable natural and man-made pressures, with a negative impact on its biodiversity and habitats. The aim was to evaluate the growth rate of invasive aquatic macrophytes and their contribution to the use of organic fertilisers: a case of Eicchornia crassipes (Mart.) Solms, 1883 in the Lobé Creek (Littoral-Cameroon) with a view to its appropriate use in agronomy. The specific objective was to examine the impact of anthropogenic actions on Lobé Creek, characterise physico-chemical environment of the study area, and evaluate the growth rate of E. crassipes and its chemical composition with a view to producing an organic biofertiliser. The results show that E. crassipes represents a considerable threat to the populations of these localities. As for the physico-chemical parameters, the temperature values vary from 24 ± 1.41˚C to 26.5 ± 1.13˚C;pH from 6.3 ± 0.1 to 7.2 ± 0.07;conductivity and dissolved oxygen vary respectively from 40.7 ± 1.83 µS/cm to 19.6 ± 3.11 µS/cm and from 7.3 ± 0.14 mg/l to 5.8 ± 1.55 mg/l. Its average growth rate varies from 0.69 feet/day to 0.63 feet/day. With regard to the nitrogen, phosphorus and potassium content of water hyacinth plants, the results show that the average total nitrogen content ranges from 6.11 ± 1.59 g/kg to 5.2 ± 2.03 g/kg;total phosphorus, from 0.52 ± 0.54 g/kg to 0.88 ± 0.38 g/kg;and potassium, from 1.43 ± 0.45 g/kg to 2.61 ± 0.89 g/kg. 展开更多
关键词 Eichhornia crassipes Lobé Creek Anthropogenic Actions Physico-Chemical Environment growth rate Chemical Composition
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Crack Growth Rate Model Derived from Domain Knowledge-Guided Symbolic Regression 被引量:1
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作者 Shuwei Zhou Bing Yang +2 位作者 Shoune Xiao Guangwu Yang Tao Zhu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第3期286-301,共16页
Machine learning(ML)has powerful nonlinear processing and multivariate learning capabilities,so it has been widely utilised in the fatigue field.However,most ML methods are inexplicable black-box models that are diffi... Machine learning(ML)has powerful nonlinear processing and multivariate learning capabilities,so it has been widely utilised in the fatigue field.However,most ML methods are inexplicable black-box models that are difficult to apply in engineering practice.Symbolic regression(SR)is an interpretable machine learning method for determining the optimal fitting equation for datasets.In this study,domain knowledge-guided SR was used to determine a new fatigue crack growth(FCG)rate model.Three terms of the variable subtree ofΔK,R-ratio,andΔK_(th)were obtained by analysing eight traditional semi-empirical FCG rate models.Based on the FCG rate test data from other literature,the SR model was constructed using Al-7055-T7511.It was subsequently extended to other alloys(Ti-10V-2Fe-3Al,Ti-6Al-4V,Cr-Mo-V,LC9cs,Al-6013-T651,and Al-2324-T3)using multiple linear regression.Compared with the three semi-empirical FCG rate models,the SR model yielded higher prediction accuracy.This result demonstrates the potential of domain knowledge-guided SR for building the FCG rate model. 展开更多
关键词 Fatigue crack growth rate Stress intensity factor range Threshold stress intensity factor range R-RATIO Symbolic regression Machine learning
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Dynamic changes of rumen microbiota and serum metabolome revealed increases in meat quality and growth performances of sheep fed bio‑fermented rice straw 被引量:1
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作者 Yin Yin Kyawt Min Aung +6 位作者 Yao Xu Zhanying Sun Yaqi Zhou Weiyun Zhu Varijakshapanicker Padmakumar Zhankun Tan Yanfen Cheng 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1207-1226,共20页
Background Providing high-quality roughage is crucial for improvement of ruminant production because it is an essential component of their feed.Our previous study showed that feeding bio-fermented rice straw(BF)improv... Background Providing high-quality roughage is crucial for improvement of ruminant production because it is an essential component of their feed.Our previous study showed that feeding bio-fermented rice straw(BF)improved the feed intake and weight gain of sheep.However,it remains unclear why feeding BF to sheep increased their feed intake and weight gain.Therefore,the purposes of this research were to investigate how the rumen micro-biota and serum metabolome are dynamically changing after feeding BF,as well as how their changes influence the feed intake,digestibility,nutrient transport,meat quality and growth performances of sheep.Twelve growing Hu sheep were allocated into 3 groups:alfalfa hay fed group(AH:positive control),rice straw fed group(RS:negative control)and BF fed group(BF:treatment).Samples of rumen content,blood,rumen epithelium,muscle,feed offered and refusals were collected for the subsequent analysis.Results Feeding BF changed the microbial community and rumen fermentation,particularly increasing(P<0.05)relative abundance of Prevotella and propionate production,and decreasing(P<0.05)enteric methane yield.The histomorphology(height,width,area and thickness)of rumen papillae and gene expression for carbohydrate trans-port(MCT1),tight junction(claudin-1,claudin-4),and cell proliferation(CDK4,Cyclin A2,Cyclin E1)were improved(P<0.05)in sheep fed BF.Additionally,serum metabolome was also dynamically changed,which led to up-regulating(P<0.05)the primary bile acid biosynthesis and biosynthesis of unsaturated fatty acid in sheep fed BF.As a result,the higher(P<0.05)feed intake,digestibility,growth rate,feed efficiency,meat quality and mono-unsaturated fatty acid concentration in muscle,and the lower(P<0.05)feed cost per kg of live weight were achieved by feeding BF.Conclusions Feeding BF improved the growth performances and meat quality of sheep and reduced their feed cost.Therefore,bio-fermentation of rice straw could be an innovative way for improving ruminant production with mini-mizing production costs. 展开更多
关键词 Bio-fermentation growth rate Meat quality METABOLOME MICROBIOTA Rice straw
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Effects of site productivity on individual tree maximum basal area growth rates of Eucalyptus pilularis in subtropical Australia
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作者 P.W.West 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1659-1668,共10页
Inventory data were available from 96 plots of even-aged,monoculture,tall-open forests of Eucalyptus pilularis Smith,aged 2-63 years,growing in sub-tropical regions along the east coast of Australia.A model was develo... Inventory data were available from 96 plots of even-aged,monoculture,tall-open forests of Eucalyptus pilularis Smith,aged 2-63 years,growing in sub-tropical regions along the east coast of Australia.A model was developed relating the maximum possible stem basal area growth rate of individual trees to their stem basal area.For any tree size,this maximum increased as site productivity increased.However,the size at which this maximum occurred decreased as productivity increased.Much research has shown that,at any stand age,trees of a particular stem basal area are taller on more productive sites than on less productive ones.Taller trees incur greater respiratory costs to ensure maintenance of the photo synthetic capacity of their canopies;this reduces their growth rates.It was concluded that trees with larger basal areas will have the maximum possible growth rate on a less productive site,whilst trees with smaller basal areas will have the maximum possible on a more productive site.The model developed may constitute the first stage of a complete individual tree growth model system to predict wood yields from these forests. 展开更多
关键词 growth model Individual tree Maximum growth rate Eucalyptus pilularis Physiological eff ects
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Aqueous extract of Protaetia brevitarsis larvae increases mTOR-mediated growth rate in zebrafish larvae
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作者 Jayasingha Arachchige Chathuranga Chanaka Jayasingha Kyoung Tae Lee +1 位作者 Yung Hyun Choi Gi-Young Kim 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2023年第8期339-347,共9页
Objective:To evaluate the effects of an aqueous extract of Protaetia brevitarsis(AEPB)on the growth of zebrafish and preosteoblast MC3T3-E1 cells.Methods:The effects of AEPB on the linear growth and the expression of ... Objective:To evaluate the effects of an aqueous extract of Protaetia brevitarsis(AEPB)on the growth of zebrafish and preosteoblast MC3T3-E1 cells.Methods:The effects of AEPB on the linear growth and the expression of growth-related genes in zebrafish and MC3T3-E1 cells were assessed using various molecular techniques.Furthermore,the involvement of the mammalian target of rapamycin(mTOR)pathway in AEPB-induced growth was investigated by employing the mTOR inhibitor rapamycin.Results:AEPB administration led to a significant and dose-dependent increase in zebrafish larvae growth over time.Additionally,AEPB treatment upregulated the expression of growth hormone-1(GH-1),insulin-like growth factor-1(IGF-1),growth hormone receptor-1(GHR-1),and cholecystokinin-a(CCKA)in zebrafish.Similarly,AEPB stimulated the expression and release of IGF-1 and accelerated mTOR expression in MC3T3-E1 cells.In addition,rapamycin hindered AEPB-induced linear growth in zebrafish larvae and suppressed the expression of growth-promoting genes by inhibiting mTOR activation.Conclusions:AEPB shows growth-promoting effects by upregulating growth-related genes and activating the mTOR signaling pathway.Further investigations are warranted to elucidate its mechanisms of action and explore its potential application in the development of growth-enhancing supplements for various purposes. 展开更多
关键词 Protaetia brevitarsis growth rate growth hormone Insulin-like growth factor MTOR MC3T3-E1
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Relationship of Trace Elements Concentration and Growth Rate in Alsidium triquetrum (Rhodophyta)
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作者 Arsenio J. Areces Ruben Cabrera +1 位作者 Jhoana Díaz-Larrea Ligia Collado-Vides 《American Journal of Plant Sciences》 CAS 2023年第3期323-338,共16页
Minerals and trace elements content and concentration in marine algae vary depending on species morphology and physiology;as well as growing environmental conditions. Despite this variability, accumulation of magnesiu... Minerals and trace elements content and concentration in marine algae vary depending on species morphology and physiology;as well as growing environmental conditions. Despite this variability, accumulation of magnesium, and especially iron, seems to be common in Chlorophyta;while Rhodophyta and Heterokontophyta show higher affinity to manganese. The red agarophyte Alsidium triquetrum was used to analyze the relationship between metal concentration, environmental conditions and growth rate. Specimens grown in situ showed a large variability of Fe, Mn, Mg, and Al, in thallus tissue concentrations. Further, a compelling relationship between the growth rate and the thallus concentration of Mg and Mn, Zn, and Al was detecte. Manganese, unlike the other trace elements analyzed showed a positive linear relationship between growth rate and tissue content during the period of greatest vegetative growth. 展开更多
关键词 Alsidium growth rate MANGANESE Trace Elements
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Growth rate of CO_(2) hydrate film on water-oil and water-gaseous CO_(2) interface
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作者 Tatyana P.Adamova Sergey S.Skiba +1 位作者 Andrey Yu.Manakov Sergey Y.Misyura 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第4期266-272,共7页
It is known that injection of carbon dioxide into the petroleum reservoir(CO_(2) flooding) is one of the effective methods for enhanced oil recovery. CO_(2) flooding may be complicated by formation of CO_(2) hydrate p... It is known that injection of carbon dioxide into the petroleum reservoir(CO_(2) flooding) is one of the effective methods for enhanced oil recovery. CO_(2) flooding may be complicated by formation of CO_(2) hydrate plugs. It makes topical investigation of CO_(2) hydrate formation in the system gaseous CO_(2)-oil-water. In this work, the growth rates of carbon dioxide hydrate films at the water-oil as well as the water-gas interface are studied in the pressure range of 2.30-3.04 MPa and at temperatures between -5.4 and 5.0℃. It is found that the growth rate for the water-oil interface is 3.5 times lower than that for the water-gas interface with carbon dioxide. It is hypothesised that the observed decrease in the growth rate is related to the mechanical resistance of the oil components adsorbed on the interface to the growth of the hydrate film. The growth rate of the film has been shown to depend on the experimental procedure,most likely due to the different initial concentrations of carbon dioxide in the aqueous solutions. 展开更多
关键词 Gas hydrate OIL Carbon dioxide growth rate Hydrate film
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RMB Exchange Rate,Overseas Education,and High-Quality Economic Growth
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作者 Sun Yuchen Sun Xianchao 《Contemporary Social Sciences》 2023年第6期97-118,共22页
China is transitioning its industrial structure from labor-and resource-intensive industries that previously contributed significantly to the country’s GDP growth to technology-intensive industries emphasizing a high... China is transitioning its industrial structure from labor-and resource-intensive industries that previously contributed significantly to the country’s GDP growth to technology-intensive industries emphasizing a highly-skilled workforce and sustainability to achieve high-quality economic growth.This paper examines the impact of the RMB exchange rate on high-quality economic growth through theoretical modeling and empirical analysis and discusses the variable of overseas education to explore the mechanism of how the RMB exchange rate and overseas education jointly impact high-quality economic growth.The research sample includes the National Bureau of Statistics data on education from 1995 to 2015,the Bank for International Settlements(BIS)data on the RMB exchange rate,and the added value of China’s high-quality economic growth estimated based on the national economy data.An empirical analysis of theoretical expectations was conducted,finding that RMB appreciation could make a positive contribution to China’s high-quality economic growth;RMB exchange rate fluctuations would impact the relative cost of overseas education and overseas returnees could have a positive impact on domestic resource utilization efficiency and domestic capacity to make sci-tech innovations,thereby injecting vitality to high-quality economic growth.This study focuses on both the RMB exchange rate and the population studying abroad,providing additional observation dimensions to existing research. 展开更多
关键词 RMB exchange rate overseas education high-quality economic growth
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Probability estimation method for fatigue crack growth rate based on a∼t data from service
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作者 Niansheng Xi Hongmin Xu 《Railway Sciences》 2023年第3期347-357,共11页
Purpose–The study aims to provide a basis for the effective use of safety-related information data and a quantitative assessment way for the occurrence probability of the safety risk such as the fatigue fracture of t... Purpose–The study aims to provide a basis for the effective use of safety-related information data and a quantitative assessment way for the occurrence probability of the safety risk such as the fatigue fracture of the key components.Design/methodology/approach–The fatigue crack growth rate is of dispersion,which is often used to accurately describe with probability density.In view of the external dispersion caused by the load,a simple and applicable probability expression of fatigue crack growth rate is adopted based on the fatigue growth theory.Considering the isolation among the pairs of crack length a and crack formation time t(a∼t data)obtained from same kind of structural parts,a statistical analysis approach of t distribution is proposed,which divides the crack length in several segments.Furthermore,according to the compatibility criterion of crack growth,that is,there is statistical development correspondence among a∼t data,the probability model of crack growth rate is established.Findings–The results show that the crack growth rate in the stable growth stage can be approximately expressed by the crack growth control curve da/dt=5 Q•a,and the probability density of the crack growth parameter Q represents the external dispersion;t follows two-parameter Weibull distribution in certain a values.Originality/value–The probability density f(Q)can be estimated by using the probability model of crack growth rate,and a calculation example shows that the estimation method is effective and practical. 展开更多
关键词 Crack growth a∼t data growth rate Probability estimation
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Bio-Fertilizer Improved Oil Palm Seedling Growth
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作者 Gabriel Ddamulira F. Masika +2 位作者 A. Asiimwe L. Zubairi M. Otuba 《American Journal of Plant Sciences》 CAS 2024年第7期455-466,共12页
In most farming systems newly introduced commercial fertilizers to be accepted, adopted and used by farmers, their effectiveness and appropriate application rates must be exhibited. This study was conducted to validat... In most farming systems newly introduced commercial fertilizers to be accepted, adopted and used by farmers, their effectiveness and appropriate application rates must be exhibited. This study was conducted to validate the effect and rates of a bio-fertilizer (super agric) on oil palm seedling growth. The trial was laid out in a randomized complete block design (RCBD) with three application rates of 0, 4 and 8 ml/L of water (treatments) replicated thrice. Following the application of super agric to oil palm seedlings for a period of six months, observations drawn from the analysis of growth data were as follows: Three months after treatment, super agric significantly (P < 0.05) increased the height and breadth of oil palm seedling compared to those which were not applied with super agric. The results also showed that when super agric was applied at a rate of 4 ml/L, the leaf length and breadth were higher compared to the control were super agric was not used. Furthermore, applications of super agric improved oil palm seedling nitrogen uptake by 31% in treatment groups as compared to the control which explained the height and breadth increase in the oil palm seedlings that were applied with super agric. On the other hand, the effect of super agric application on phosphorus uptake by seedlings was not significant. Although the height, breadth, leaf width and length were all significantly affected by super agric application, the number of oil palm leaves and spears were not affected for the period the experiment was conducted. Six months after application of super agric the growth of oil palm seedlings was favorably impacted, hence we recommend super agric to be promoted among oil palm seedling growers. 展开更多
关键词 BIO-FERTILIZER SEEDLING growth APPLICATION rates Super Agric
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Post Cryopreservation Growth Kinetic and Photosynthetic Assessment of an Acid Tolerant Strain of Stichococcus bacillaris
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作者 Marzia Licata Luigi Marra +5 位作者 Nunzia Nappi Elena Aurino Feliciana Oliva Antonino De Natale Donato Giovannelli Antonino Pollio 《Natural Resources》 2024年第5期130-148,共19页
Preserving microbial diversity has become a strategic undertaking. Thus, ex situ microalgal culture conservation results in strategic and functional resource in both biodiversity protection and application domains. Cr... Preserving microbial diversity has become a strategic undertaking. Thus, ex situ microalgal culture conservation results in strategic and functional resource in both biodiversity protection and application domains. Cryopreservation of microalgae has been practiced since the 1960s and is now considered the optimal preservation strategy. Furthermore, the overall monitoring during growth of cultures after freezing/thawing protocols was hardly investigated and there is poor evaluation related to preserve especially the photosystem apparatus. The present study focuses on Stichococcus bacillaris as case study for short-term cryopreservation at −80 °C storage. Various freezing pretreatments using cryoprotective agents, and two thawing methods were compared introducing a novel variable to evaluate viability recovery and assessing growth kinetics of cultures immediately after thawing and after a series batch cultivation. Photosynthetic rate and pigments assessment were proposed to evaluate hidden metabolic cell damage. Results underline cryoprotective agents can increase the kinetic recovery of preserved cells in terms of reduction of lag phase during batch cultivation tests: the use of dimethyl sulfoxide and glycerol granted a growth comparable to unpreserved cells when sudden thawing occurs after 24 hours of storage, but recovery after preservation is less sensitive to cryoprotective agents when gradual thawing and 1 month of storage is considered. However, cells are always able to restore their physiological pathways even without agents, so their kinetic effect has been proved and quantified. Interestingly, both the photosynthetic efficiency and the ratio between total chlorophyll and carotenoids are comparable (0.75 F<sub>v</sub>/F<sub>m</sub>, 2.2 ± 0.25 g/g) to unpreserved cells and they are unsensitive to chosen agents, but the ratio between chlorophyll a and chlorophyll b was clearly altered (up to 10 times), suggesting that photoactive pigments relative proportions can result in similar growth kinetic performances. Long-term studies will be carried out to assess whether the differences found could cause chronic damage to photosystem efficiency of S. bacillaris cultures. 展开更多
关键词 MICROALGAE Stichococcus bacillaris CRYOPRESERVATION growth Kinetic Photosynthetic rate
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Effect of growth rate and diameter on microstructure and hardness of directionally solidified Ti-46Al-8Nb alloy 被引量:2
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作者 刘国怀 李新中 +6 位作者 张元 陈瑞润 苏彦庆 郭景杰 傅恒志 王昭东 王国栋 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期4044-4052,共9页
Bridgman-type directional solidification experiments were conducted for Ti-46Al-8Nb (mole fraction, %) alloy. The effects of the growth rate and the diameter on the microstructure, phase transition and hardness of t... Bridgman-type directional solidification experiments were conducted for Ti-46Al-8Nb (mole fraction, %) alloy. The effects of the growth rate and the diameter on the microstructure, phase transition and hardness of the alloy were investigated. The results show that with the increase of the growth rate and the decrease of the diameter, the fullyβphase solidification changes to the peritectic solidification, and the final microstructure is composed of theα2/γlamellar structure and a multiphase microstructure (B2 phase,α2/γlamellar structure) respectively, which can be attributed to the solute enrichment resulting from the decreasing diffusion and convection ability. The occurrence of peritectic reaction at high growth rate promotes the solute segregation heavily and the coarse lamellar spacing in Al-and Nb-rich region, which greatly decreases the hardness values and leads to the discontinuity of the hardness curves with the increase of the growth rate. Comparatively, the Ti-46Al-8Nb alloy has lower hardness values than the other applied TiAl-based alloys in previous studies. 展开更多
关键词 TiAl alloy directional solidification growth rate DIAMETER phase transition
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Supply-Side Structural Reforms and China's Potential Economic Growth Rate 被引量:10
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作者 李平 娄峰 《China Economist》 2016年第4期4-21,共18页
This paper examines the effect of supply-side structural reforms on China's potential economic growth rate in the coming decade according to the data the authors have gathered. Under the rapid growth scenario with th... This paper examines the effect of supply-side structural reforms on China's potential economic growth rate in the coming decade according to the data the authors have gathered. Under the rapid growth scenario with the implementation of supply-side structural reforms, China's potential economic growth rate will reach an average of 6.5% and 5.8% respectively in the 13th Five-year Plan (2016-2020) and 14th Five-year Plan (2021-2025) periods. These rates are 0.2 and 0.3 percentage points higher, respectively, than that under the baseline scenario with the inertia of historic trends. In implementing supply-side structural reforms, China must transform governmental functions, break monopolies, create a comprehensive competitive market environment, foster the creation of pro-innovation mechanisms, refocus on quality and efficiency, and raise capital utilization and labor productivity. 展开更多
关键词 supply-side structural reforms potential economic growth rate TFP China'seconomy
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Studies on the Isolation, Identification and In Vitro Growth Rates of the Three Pathogenic Fungi from Panax notoginseng Cultivated in Wenshan Eparchy 被引量:2
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作者 王文亚 赵昶灵 +5 位作者 陈中坚 文国松 魏富刚 龙廷菊 李孙文 王崇德 《Agricultural Science & Technology》 CAS 2015年第6期1165-1171,1258,共8页
Objective] The aim of this study was to simultaneously isolate and identify the main pathogenic fungi of the root rot, black spot and round spot from the Panax notoginseng plants cultivated in Wenshan Eparchy of Yunna... Objective] The aim of this study was to simultaneously isolate and identify the main pathogenic fungi of the root rot, black spot and round spot from the Panax notoginseng plants cultivated in Wenshan Eparchy of Yunnan Province of China. [Method] The pathogenic fungi were isolated and purified by using potato dextrose agar (PDA) medium. The morphological identification was accomplished first according to the colony forms of the fungi when cultivated in vitro, then accord-ing to the symptom characteristics and colony forms of the re-isolated fungi in the reverse inoculation experiments. The molecular identification was performed accord-ing to the amplification and alignment of the internal transcribed space (ITS) se-quences of the fungi. The increases of the diameters and thickness of the colonies of the fungi cultivated in vitro were employed to indicate the growth rates of the fungi. [Results] The consistency of the colony forms and symptom characteristics and the 96%-99% similarities revealed in the ITS sequence alignments al proved that the main pathogenic fungi of the root rot, black spot and round spot of the P. notoginseng plants raised in Wenshan were Cylindrocarpon didymium, Alternaria panax and Mycocentrospora acerina, respectively. When cultivated in vitro in the same temperature, humidity and il umination, the increases of the colony diameters and thickness of C. didymium were the highest, fol owed by those of A. panax, then those of M. acerina. During different cultivation periods, the differences of the colony diameters and thickness of the three fungi al reached extremely significant level. However, at the same cultivation time, the differences of the diameters and thickness among the three fungi only reached significant level. [Conclusion] The main pathogenic fungi which result in the root rot, black spot and round spot of the P. notoginseng in Wenshan are C. didymium, A. panax and M. acerina, respec-tively. When these three diseases break out at the same time, the root rot wil spread fastest, fol owed orderly by the black spot and the round spot. 展开更多
关键词 Panax notoginseng cultivated in Wenshan Eparchy Root rot black spot and round spot Pathogenic fungus growth rate in vitro
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Setting China’s Growth Target Based on the Potential Growth Rate 被引量:1
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作者 蔡昉 陆旸 《China Economist》 2015年第2期6-21,共16页
Different from other methodologies for the forecasting of China's economic growth rate, this paper forecast of future potential growth rates from the end of China's demographic dividends, and then identified it as a... Different from other methodologies for the forecasting of China's economic growth rate, this paper forecast of future potential growth rates from the end of China's demographic dividends, and then identified it as a growth target. Official promulgation of non-binding targets will guide social expectation, assist in government policy-making, boost confidence in consumers, and provide guidance for producers and investors. Based on our estimation results, we suggest that during the 13th Five-Year Plan period, a GDP growth target between 6. 5% and 7% would be appropriate. 展开更多
关键词 potential growth rate growth target demographic dividends reform dividends
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PROBABILISTIC MODELS FOR LONG FATIGUE CRACK GROWTH RATES OF LZ50 AXLE STEEL 被引量:5
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作者 赵永翔 何朝明 +3 位作者 杨冰 黄郁仲 高庆 邬平波 《应用数学和力学》 CSCD 北大核心 2005年第8期997-1002,共6页
Experimental study is performed on the probabilistic models for the long fatigue crack growth rates (da/dN) of LZ50 axle steel. An equation for crack growth rate was derived to consider the trend of stress intensity f... Experimental study is performed on the probabilistic models for the long fatigue crack growth rates (da/dN) of LZ50 axle steel. An equation for crack growth rate was derived to consider the trend of stress intensity factor range going down to the threshold and the average stress effect. The probabilistic models were presented on the equation. They consist of the probabilistic da/dN-ΔK relations, the confidence-based da/dN-ΔK relations, and the probabilistic- and confidence-based da/dN-ΔK relations. Efforts were made respectively to characterize the effects of probabilistic assessments due to the scattering regularity of test data, the number of sampling, and both of them. These relations can provide wide selections for practice. Analysis on the test data of LZ50 steel indicates that the present models are available and feasible. 展开更多
关键词 LZ50钢 疲劳长裂纹 扩展率 平均应力 门槛值 概率模型
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Rates of generation and growth of the continental crust 被引量:15
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作者 Chris Hawkesworth Peter A.Cawood Bruno Dhuime 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第1期165-173,共9页
Models for when and how the continental crust was formed are constrained by estimates in the rates o crustal growth. The record of events preserved in the continental crust is heterogeneous in time with distinctive pe... Models for when and how the continental crust was formed are constrained by estimates in the rates o crustal growth. The record of events preserved in the continental crust is heterogeneous in time with distinctive peaks and troughs of ages for igneous crystallisation, metamorphism, continental margin and mineralisation. For the most part these are global signatures, and the peaks of ages tend to b associated with periods of increased reworking of pre-existing crust, reflected in the Hf isotope ratios o zircons and their elevated oxygen isotope ratios. Increased crustal reworking is attributed to periods o crustal thickening associated with compressional tectonics and the development of supercontinents Magma types similar to those from recent within-plate and subduction related settings appear to hav been generated in different areas at broadly similar times before ~3.0 Ga. It can be difficult to put th results of such detailed case studies into a more global context, but one approach is to consider when plate tectonics became the dominant mechanism involved in the generation of juvenile continental crust The development of crustal growth models for the continental crust are discussed, and a number o models based on different data sets indicate that 65%-70% of the present volume of the continental crus was generated by 3 Ga. Such estimates may represent minimum values, but since ~3 Ga there has been reduction in the rates of growth of the continental crust. This reduction is linked to an increase in th rates at which continental crust is recycled back into the mantle, and not to a reduction in the rates a which continental crust was generated. Plate tectonics results in both the generation of new crust and it destruction along destructive plate margins. Thus, the reduction in the rate of continental crustal growth at ~3 Ga is taken to reflect the period in which plate tectonics became the dominant mechanism b which new continental crust was generated. 展开更多
关键词 CONTINENTAL CRUST growth curves rates of CRUSTAL growth TECTONICS
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STUDIES ON CULTURE CONDITIONS OF BENTHIC DIATOMS FOR FEEDING ABALONE Ⅲ. EFFECTS OF IRON AND SILICON NUTRIENTS AND OF ORTHOGONAL COMBINATIONS OF NITROGEN,PHOSPHORUS,IRON AND SILICON ON GROWTH RATE 被引量:5
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作者 王起华 李雅娟 李梅 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1999年第2期105-111,共7页
Effects of iron and silicon nutrients and of orthogonal combinations of nitrogen, phosphorus, iron and silicon on the growth rate of three benthic diatoms were studied by using an in situ OD measurement method. The re... Effects of iron and silicon nutrients and of orthogonal combinations of nitrogen, phosphorus, iron and silicon on the growth rate of three benthic diatoms were studied by using an in situ OD measurement method. The results of monofactor tests of ironand silicon shawed that Fe-EDTA was bettef than ferric citrate in the culture of these diatoms;that the favourable concentration of Fe-EDTA was about 0.5 mg/L of Fe and that of silicate was 2.5 mg/L of Si or more.The orthogonal test showed that the optimal concentration ratios(mg/L)of nitrogen, phosphorus, iron and silicon were: 5. 0: 0. 25: 0.5: 2. 0 for Cocconeis scutellum var. parva; 2.5: 1.0: 1.0: 2.0 for Amphora coffeaeformis; and 5.0: 0. 15: 0.5: 2.0 for N. mollis. 展开更多
关键词 benthic DIATOMS NUTRIENTS ORTHOGONAL test growth rate
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