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Different concentrations of hyaluronic acid eye drops for dry eye syndrome: a systematic review and Meta-analysis
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作者 Xiao-Wei Ouyang Sheng Fang +5 位作者 Yun-Min Yi Shi-Peng Zou Qi-Yu Hu Zi-Xuan Huang Qing-Xia Li Jin-Yan Luo 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第6期1110-1119,共10页
AIM:To compare high or low concentration of hyaluronic acid eye drops(HY)for dry eye syndromes(DES).METHODS:Randomized controlled trials(RCTs)comparing various concentrations of HY were searched in PubMed,Embase,Web o... AIM:To compare high or low concentration of hyaluronic acid eye drops(HY)for dry eye syndromes(DES).METHODS:Randomized controlled trials(RCTs)comparing various concentrations of HY were searched in PubMed,Embase,Web of Science,Cochrane,SinoMed,CNKI,Wanfang Database,CQVIP,and Chinese journals databases between inception and July 2023.Pooled standardized mean differences(SMD)or weighted mean difference(WMD)with 95%confidence intervals(CI)from RCTs evaluating Schirmer’s I test(SIT),corneal fluorescein staining score(CFS),tear breakup time(TBUT),DES score(DESS),and Ocular Surface Disease Index(OSDI)were calculated.Sensitivity analysis,Egger’s test and Meta-regression analysis were performed for all indicators.RESULTS:We conducted a Meta-analysis of 10 RCTs that met the inclusion criteria,involving 1796 cases.High-concentrations group significantly improved the outcome of CFS according to random effects modelling(SMD,-3.37;95%CI,-5.25 to-1.48;P=0.0005).The rest of the results were not statistically significant,including indicators such as SIT,TBUT,DESS and OSDI.CONCLUSION:For dry eyes with positive corneal staining,a high concentration of HY is recommended,whereas in other cases,a high concentration of HY does not offer a more pronounced advantage over a low concentration of HY in the treatment of dry eyes. 展开更多
关键词 dry eye hyaluronic acid concentration META-ANALYSIS
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Analysis of Air Exchange System Influence on Thermal and Concentration Modes in the Local Working Area under Radiant Heating Conditions
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作者 Boris Borisov Geniy Kuznetsov +2 位作者 Vyacheslav Maksimov Tatiana Nagornova Felix Salikhov 《Frontiers in Heat and Mass Transfer》 EI 2024年第6期1597-1612,共16页
One of the effective options for energy saving in terms of heat costs for the formation of routine thermal conditions of working areas of large-sized industrial premises is the replacement of traditional convective(wa... One of the effective options for energy saving in terms of heat costs for the formation of routine thermal conditions of working areas of large-sized industrial premises is the replacement of traditional convective(water)heating systems with systems,the main part of which are gas infrared emitters.But the mass introduction of such systems based on emitters was held back until recently by the lack of scientific and technical foundations for ensuring not only the routine thermal conditions of local working areas,but also ensuring acceptable concentrations of carbon dioxide,which is formed during the operation of a gas emitter.Solving the latter problem by the method of experimental selection of heating and air exchange modes is practically impossible due to the multivariate nature of possible solutions to this problem.Therefore,the purpose of the work is to analyze the results of theoretical studies of the possibility of ensuring an acceptable level of carbon dioxide concentrations in local working areas during the operation of gas infrared emitters and an air exchange system.Numerical modeling of heat and mass transfer processes under such conditions was performed in a fairly wide range of the main significant factors:air flow rate in the air exchange system from 0.01 to 0.04 kg/s,the position of the air inlet and outlet channels relative to the radiator and the local workplace(height from 0.3 to 4.1 m).It was found that by varying the numerical values of these factors,it is possible to ensure carbon dioxide concentrations in the local working area within the permissible limits of up to 1400 ppm. 展开更多
关键词 Gas infrared heater air exchange system local working areas temperature fields CO_(2)concentration fields
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Vedolizumab serum trough concentrations with and without thiopurines in ulcerative colitis: The prospective VIEWS pharmacokinetics study
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作者 Thanaboon Chaemsupaphan Aviv Pudipeddi +4 位作者 Hui-Yu Lin Sudarshan Paramsothy Viraj C Kariyawasam Melissa Kermeen Rupert W Leong 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期102-112,共11页
BACKGROUND Ulcerative colitis(UC)is a chronic inflammatory condition requiring continuous treatment and monitoring.There is limited pharmacokinetic data on vedolizumab during maintenance therapy and the effect of thio... BACKGROUND Ulcerative colitis(UC)is a chronic inflammatory condition requiring continuous treatment and monitoring.There is limited pharmacokinetic data on vedolizumab during maintenance therapy and the effect of thiopurines on vedolizumab trough concentrations is unknown.AIM To investigate the exposure-response relationship of vedolizumab and the impact of thiopurine withdrawal in UC patients who have achieved sustained clinical and endoscopic remission during maintenance therapy.METHODS This is a post-hoc analysis of prospective randomized clinical trial(VIEWS)involving UC patients across 8 centers in Australia from 2018 to 2022.Patients in clinical and endoscopic remission were randomized to continue or withdraw thiopurine while receiving vedolizumab.We evaluated vedolizumab serum trough concentrations,presence of anti-vedolizumab antibodies,and clinical outcomes over 48 weeks to assess exposure-response asso-ciation and impact of thiopurine withdrawal.RESULTS There were 62 UC participants with mean age of 43.4 years and 42%were females.All participants received vedolizumab as maintenance therapy with 67.7%withdrew thiopurine.Vedolizumab serum trough concentrations remained stable over 48 weeks regardless of thiopurine use,with no anti-vedolizumab antibodies detected.Pa-tients with clinical remission had higher trough concentrations at week 48.In quartile analysis,a threshold of>11.3μg/mL was associated with sustained clinical remission,showing a sensitivity of 82.4%,specificity of 60.0%,and an area of receiver operating characteristic of 0.71(95%CI:0.49-0.93).Patients discontinuing thiopurine required higher vedolizumab concentrations for achieving remission.CONCLUSION A positive exposure-response relationship between vedolizumab trough concentrations and UC outcomes suggests that monitoring drug levels may be beneficial.While thiopurine did not influence vedolizumab levels,its with-drawal may necessitate higher vedolizumab trough concentrations to maintain remission. 展开更多
关键词 PHARMACOKINETIC Vedolizumab THIOPURINE Ulcerative colitis Trough concentration Antibody Inflammatory bowel diseases
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Impact of Pollutant Concentration and Particle Deposition on the Radiative Flow of Casson-Micropolar Fluid between Parallel Plates
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作者 Ghaliah Alhamzi Badr Saad T.Alkahtani +2 位作者 Ravi Shanker Dubey Vinutha Kalleshachar Neelima Nizampatnam 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期665-690,共26页
Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing po... Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing pollution scales is made easier by analysing waste discharge concentrations.The waste discharge concentration analysis is useful for assessing how effectively wastewater treatment techniques reduce pollution levels.This study aims to explore the Casson micropolar fluid flow through two parallel plates with the influence of pollutant concentration and thermophoretic particle deposition.To explore the mass and heat transport features,thermophoretic particle deposition and thermal radiation are considered.The governing equations are transformed into ordinary differential equations with the help of suitable similarity transformations.The Runge-Kutta-Fehlberg’s fourthfifth order technique and shooting procedure are used to solve the reduced set of equations and boundary conditions.The integration of a neural network model based on the Levenberg-Marquardt algorithm serves to improve the accuracy of predictions and optimize the analysis of parameters.Graphical outcomes are displayed to analyze the characteristics of the relevant dimensionless parameters in the current problem.Results reveal that concentration upsurges as the micropolar parameter increases.The concentration reduces with an upsurge in the thermophoretic parameter.An upsurge in the external pollutant source variation and the local pollutant external source parameters enhances mass transport.The surface drag force declines for improved values of porosity and micropolar parameters. 展开更多
关键词 Micropolar fluid thermal radiation porous medium thermophoretic particle deposition waste discharge concentration
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Effect of Coffee Aroma on Cerebral Activity during Concentration Tasks
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作者 Moemi Matsuo Taiyo Ichibakase +2 位作者 Hikaru Suyama Runa Takahara Takashi Higuchi 《Open Journal of Applied Sciences》 2025年第1期137-146,共10页
Caffeine has been shown to reduce various health risks, such as diabetes, obesity, and vascular diseases, and it may provide health benefits when consumed in moderate amounts, such as three to four cups per day. Howev... Caffeine has been shown to reduce various health risks, such as diabetes, obesity, and vascular diseases, and it may provide health benefits when consumed in moderate amounts, such as three to four cups per day. However, caffeine may exhibit harmful effects depending on the dose. Although the health benefits and disadvantages of caffeine intake have been studied, the effects of caffeine’s aroma have hardly been studied. This study aimed to examine the impact of caffeine scent on brain activity during cognitive tasks using electroencephalography (EEG). This study included 30 healthy young adults. We investigated cerebral activity using EEG during the concentration tasks. Participants performed tasks under pre- and post-conditions, including drinking coffee, smelling coffee, or drinking water. The number of correct responses and reaction times were calculated for each task, and mean power levels were analyzed. A linear mixed model was applied with “performance”, “ROI”, and “wave band” to examine the effects of conditions and timing. Significant differences were observed in left-frontal θ power (coffee α power (coffee P θ between pre- and post-task during water conditions (pre α on the frontal lobe and higher θ are associated with improved arousal and cognitive functions. Drinking coffee reduced α power, whereas smelling coffee or drinking water increased θ power. Therefore, drinking coffee, smelling coffee, and drinking water may affect cerebral activities and enhance cognitive performance. 展开更多
关键词 COFFEE CAFFEINE concentration ELECTROENCEPHALOGRAPHY Brain Function NEUROIMAGING
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Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent
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作者 H.HOSSEINI O.BALILASHAKI 《Applied Mathematics and Mechanics(English Edition)》 2025年第1期139-156,共18页
The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically.It is assu... The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically.It is assumed that the source is located outside the cavity at a specified distance from the borehole axis.The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed.Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid,empty borehole,and rigid inclusion with a hard boundary is employed for the analysis.Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions,the proposed boundary conditions at the interface are satisfied.Stresses are formulated by means of wave potential functions in a three-dimensional(3D)manner.The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra.Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis.To give an overall outline of the study,a numerical example is presented.The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values.In addition,the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole.Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases,and good agreement is achieved. 展开更多
关键词 point source cylindrical cavity porous medium wave-field transformation stress concentration
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Significance of monitoring imatinib plasma concentration in secondline treatment decisions for c-kit 11 gene-mutated gastrointestinal stromal tumors
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作者 Hai-Tao Li Yun-Yun Du +2 位作者 Zhen Huang Jin-Jin Li Jun Zhang 《World Journal of Gastrointestinal Oncology》 2025年第3期81-90,共10页
BACKGROUND For patients with advanced gastrointestinal stromal tumors(GISTs)carrying the ckit exon 11 mutation,imatinib(IM)at a standard dosage of 400 mg per day is the preferred first-line treatment.In cases where tr... BACKGROUND For patients with advanced gastrointestinal stromal tumors(GISTs)carrying the ckit exon 11 mutation,imatinib(IM)at a standard dosage of 400 mg per day is the preferred first-line treatment.In cases where treatment with IM fails,there is an urgent need for a more precise assessment method to determine whether to switch therapies or escalate the IM dosage.This approach will enhance clinical decision-making and optimize patient outcomes.AIM To investigate IM plasma concentration’s role in second-line treatment decisions for c-kit 11-mutated advanced GISTs post-IM failure.METHODS Patients with advanced GIST harboring c-kit 11 mutation who experienced failure with IM 400 mg per day as first-line treatment at our hospital were retrospectively analyzed.Patients were categorized into a low plasma(LP)concentration group(LP group,<1100 ng/mL)and high plasma(HP)concentration group(HP group,≥1100 ng/mL).Each group was further subdivided into Group A(dose-escalation group)and Group B(drug-switch group).Baseline characteristics were compared and Kaplan-Meier curves were used to analyze the survival of patients.RESULTS Seventy-five patients were included in the analysis.For the LP group(n=28),Group A(n=14)had longer overall survival(OS)than Group B(n=14)(P=0.02).No differences were observed between the two subgroups in disease control rate(DCR),objective response rate,and progression-free survival(PFS)(P>0.05).For the HP group(n=47),Group B(n=18)had a higher DCR and longer PFS than Group A(n=29)(P=0.008 and P=0.03,respectively).No difference in OS was observed between the two subgroups(P>0.05).CONCLUSION Increasing IM dosage for c-kit 11-mutated advanced GISTs post-IM failure may prolong OS if plasma concentration is<1100 ng/mL.Switching tyrosine kinase inhibitors may improve DCR and PFS if≥1100 ng/mL. 展开更多
关键词 Gastrointestinal stromal tumor C-kit exon 11 IMATINIB Plasma concentration Second-line treatment
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Correlations of vancomycin trough concentration and its efficacy and toxicity in patients in the intensive care unit
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作者 Teng Guo Li-Ying Du +2 位作者 Ming-Feng Liu Xia-Jin Zhou Xin-Ran Chen 《World Journal of Clinical Cases》 2025年第16期18-28,共11页
BACKGROUND Plasma concentration monitoring is crucial for optimizing vancomycin use,particularly in patients in the intensive care unit(ICU).However,the reference interval for vancomycin plasma concentration remains u... BACKGROUND Plasma concentration monitoring is crucial for optimizing vancomycin use,particularly in patients in the intensive care unit(ICU).However,the reference interval for vancomycin plasma concentration remains undetermined.AIM To evaluate the correlations of area under the curve(AUC_(0-24))and trough concentration(C_(min))with efficacy and nephrotoxicity in patients in the ICU.METHODS A total of 103 patients treated with vancomycin for methicillin-resistant Staphylococcus aureus infections were analyzed in this study.The associations of clinicodemographic characteristics(including sex,age,weight,infection sites,main etiologies of ICU cases,comorbidities,acute physiological chronic health evaluation II score,and mechanical ventilation)and pharmacokinetics(daily dose,C_(min),AUC_(0-24),and AUC_(0-24)/minimum inhibitory concentration)with efficacy and nephrotoxicity of vancomycin were evaluated with univariate and multivariate logistic regression analyses.AUC_(0-24)was calculated using VCM-TDM software based on vancomycin population pharmacokinetics and Bayesian feedback method.RESULTS Cmin over 9.4μg/mL and AUC_(0-24)exceeding 359.6μg×hour/mL indicated good efficacy against infection.Cmin below 14.0μg/mL predicted no significant nephrotoxicity.CONCLUSION In this study,the effective and safe concentration interval for vancomycin in patients in the ICU was Cmin 9.4-14.0μg/mL.Close attention should be paid to adverse effects and renal function during vancomycin treatment. 展开更多
关键词 VANCOMYCIN Therapeutic drug monitoring Intensive care unit Trough concentration Methicillin-resistant Staphylococcus aureus infection Area under the curve
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A novel method for simultaneous measurement of^(222)Rn and^(220)Rn progeny concentrations measured by an alpha spectrometer
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作者 Zhong-Kai Fan Jia-Le Sun +5 位作者 Hao-Xuan Li Xiang-Ming Cai Hui Yang Shou-Kang Qiu Yan-Liang Tan Jian Shan 《Nuclear Science and Techniques》 2025年第1期127-139,共13页
The accumulation of^(222)Rn and^(220)Rn progeny in poorly ventilated environments poses the risk of natural radiation exposure to the public.A previous study indicated that satisfactory results in determining the^(222... The accumulation of^(222)Rn and^(220)Rn progeny in poorly ventilated environments poses the risk of natural radiation exposure to the public.A previous study indicated that satisfactory results in determining the^(222)Rn and^(220)Rn progeny concentrations by measuring the total alpha counts at five time intervals within 560 min should be expected only in the case of high progeny concentrations in air.To complete the measurement within a relatively short period and adapt it for simultaneous measurements at comparatively lower^(222)Rn and^(220)Rn progeny concentrations,a novel mathematical model was proposed based on the radioactive decay law.This model employs a nonlinear fitting method to distinguish nuclides with overlapping spectra by utilizing the alpha particle counts of non-overlapping spectra within consecutive measurement cycles to obtain the concentrations of^(222)Rn and^(220)Rn progeny in air.Several verification experiments were conducted using an alpha spectrometer.The experimental results demonstrate that the concentrations of^(222)Rn and^(220)Rn progeny calculated by the new method align more closely with the actual circumstances than those calculated by the total count method,and their relative uncertainties are all within±16%.Furthermore,the measurement time was reduced to 90 min,representing an acceleration of 84%.The improved capability of the new method in distinguishing alpha particles with similar energies emitted from ^(218)Po and^(212)Bi,both approximately 6 MeV,contributed to realizing more accurate results.The proposed method has the potential advantage of measuring relatively low concentrations of^(222)Rn and^(220)Rn progeny in air more quickly via air filtration. 展开更多
关键词 ^(222)Rn ^(220)Rn Progeny concentration Nonlinear fitting method Alpha spectrometer
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Optimization of the in Vitro Fertilization System in Cỏ Goat Oocytes
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作者 Van Khanh Nguyen Huong Thi Thu Vu +6 位作者 Au Thi Hoang Yen Thi Kim Pham Dat Van Le Quan Xuan Huu Lan Anh Thi Nguyen Huong Le Thi Nguyen Lan Doan Pham 《Open Journal of Animal Sciences》 2025年第1期39-50,共12页
This study aimed to optimization of the in vitro fertilization system in Cỏ goat oocytes to achieve the maximum possible blastocyst development rate. In Experiment 1, we assessed the effects of IVF media on the in vit... This study aimed to optimization of the in vitro fertilization system in Cỏ goat oocytes to achieve the maximum possible blastocyst development rate. In Experiment 1, we assessed the effects of IVF media on the in vitro fertilization of Cỏ goat oocytes. There was no significant difference in the cleavage, blastocyst, or hatching rates between TALP-Fert and BO-IVF media. Experiment 2 was performed to assess the concentration of sperm in the in vitro fertilization of Cỏ goat oocytes. The matured Cỏ goat oocytes were fertilized in BO-IVF for four sperm concentrations: 5 × 105, 1 × 106, 2 × 106 and 3 × 106 sperm/ml. The blastocyst rate of 2 × 106 sperm/ml and 3 × 106 sperm/ml groups was higher than that of 5 × 105 sperm/ml and 1 × 106 sperm/ml groups (P Experiment 3 was performed to assess the IVF duration on the in vitro fertilization of Cỏ goat oocytes. The matured Cỏ goat oocytes were fertilized in BO-IVF with sperm concentration of 3 × 106 sperm/ml for 18, 20, 22 and 24 h. The cleavage, blastocyst, and hatching blastocyst rates of 18 h group were lower than those of 20, 22 and 24 h groups (P 0.05). In conclusion, the matured Cỏ goat oocytes were fertilized in BO-IVF with sperm concentration of 3 × 106 sperm/ml for 20 hours, which is suitable for the in vitro Cỏ goat embryo production. 展开更多
关键词 Cỏ Goat Oocytes In Vitro Fertilizaition Media In Vitro Fertilizaition Duration Sperm concentration In Vitro Embryos
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Low-Carbon Economic Dispatch Strategy for Integrated Energy Systems under Uncertainty Counting CCS-P2G and Concentrating Solar Power Stations
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作者 Zhihui Feng Jun Zhang +5 位作者 Jun Lu Zhongdan Zhang Wangwang Bai Long Ma Haonan Lu Jie Lin 《Energy Engineering》 2025年第4期1531-1560,共30页
In the background of the low-carbon transformation of the energy structure,the problem of operational uncertainty caused by the high proportion of renewable energy sources and diverse loads in the integrated energy sy... In the background of the low-carbon transformation of the energy structure,the problem of operational uncertainty caused by the high proportion of renewable energy sources and diverse loads in the integrated energy systems(IES)is becoming increasingly obvious.In this case,to promote the low-carbon operation of IES and renewable energy consumption,and to improve the IES anti-interference ability,this paper proposes an IES scheduling strategy that considers CCS-P2G and concentrating solar power(CSP)station.Firstly,CSP station,gas hydrogen doping mode and variable hydrogen doping ratio mode are applied to IES,and combined with CCS-P2G coupling model,the IES low-carbon economic dispatch model is established.Secondly,the stepped carbon trading mechanism is applied,and the sensitivity analysis of IES carbon trading is carried out.Finally,an IES optimal scheduling strategy based on fuzzy opportunity constraints and an IES risk assessment strategy based on CVaR theory are established.The simulation shows that the gas-hydrogen doping model proposed in this paper reduces the operating cost and carbon emission of IES by 1.32%and 7.17%,and improves the carbon benefit by 5.73%;variable hydrogen doping ratio model reduces the operating cost and carbon emission of IES by 3.75%and 1.70%,respectively;CSP stations reduce 19.64%and 38.52%of the operating costs of IES and 1.03%and 1.80%of the carbon emissions of IES respectively compared to equal-capacity photovoltaic and wind turbines;the baseline price of carbon trading of IES and its rate of change jointly affect the carbon emissions of IES;evaluating the anti-interference capability of IES through trapezoidal fuzzy number and weighting coefficients,enabling IES to guarantee operation at the lowest cost. 展开更多
关键词 Concentrating solar power station CCS-P2G stepped carbon trading mechanism fuzzy opportunity constraints conditional value-at-risk theory
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Changes of nutrient concentrations and N:P:Si ratios and their possible impacts on the Huanghai Sea ecosystem 被引量:16
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作者 FU Mingzhu WANG Zongling +2 位作者 PU Xinming XU Zongjun ZHU Mingyuan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第4期101-112,共12页
To investigate the impacts of nutrient concentrations and N:P:Si ratios on the ecosystem of the Huanghai Sea (Yellow Sea), the current status and long-term variation of nutrients concentrations and ratios as well ... To investigate the impacts of nutrient concentrations and N:P:Si ratios on the ecosystem of the Huanghai Sea (Yellow Sea), the current status and long-term variation of nutrients concentrations and ratios as well as phytoplankton community structure in the Huanghai Sea were collected and analyzed. The results reveal great annual and seasonal fluctuations in the nutrient concentrations and N:P:Si ratios during 1998-2008 with no clear pattern observed in the whole region. Yet on a seasonal scale of spring and in the coastal regions such as the Jiaozhou Bay and Sanggou Bay, the increase of DIN concentration and N:P ratio as well as the decrease of phosphate and sili- cate concentrations and Si:N ratios were relatively significant. Many pelagic ecosystem changes have occurred concurrent with these changes of the nutrient regime, such as the recent increase of primary production, changes of phytoplankton chlorophyll a biomass and abundance, an increase of eutrophication, and occurrence of HABs. In addition, new trends in the variation of nutrients seem to be developing in some particular transect such as 36N, which suggests that long-term and systematic ecosystem monitoring in the Huanghai Sea is necessary. 展开更多
关键词 nutrient concentration and ratio long-term variation Huanghai Sea ecosystemresponse
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Universal thermodynamic model of calculating the mass action concentrations of omponents in a ternary strong electrolyte aqueous solution and its application in the NaCl-KCl-H_2O system 被引量:5
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作者 Weijie Zhao Hanjie Guo +1 位作者 Xuemin Yang Zhigang Dan 《Journal of University of Science and Technology Beijing》 CSCD 2008年第5期543-551,共9页
A universal thermodynamic model of calculating the mass action concentrations of components in a ternary strong electrolyte aqueous solution has been developed based on the ion and molecule coexistence theory,and veri... A universal thermodynamic model of calculating the mass action concentrations of components in a ternary strong electrolyte aqueous solution has been developed based on the ion and molecule coexistence theory,and verified in the NaCl-KCl-H2O ternary system at 298.15 K. To compare the difference of the thermodynamic model in binary and ternary strong electrolyte aqueous solutions,the mass action concentrations of components in the NaCl-H2O binary strong electrolyte aqueous solution were also computed at 298.15K. A transformation coefficient was required to compare the calculated mass action concentration and reported activity because they were obtained at different standard states and concentration units. The results show that the transformation coefficients between calculated mass action concentrations and reported activities of the same components change in a very narrow range. The calculated mass action concentrations of components in the NaCl-H2O and NaCl-KCl-H2O systems are in good agreement with the reported activities. This indicates that the developed thermodynamic model can reflect the structural characteristics of solutions,and the mass action concentration also strictly follows the mass action law. 展开更多
关键词 mass action concentration activity ternary system binary system ion and molecule coexistence theory transformation coefficient
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Influence of high concentration Zn^(2+) on floatability of sphalerite in acidic system 被引量:4
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作者 Ting-sheng QIU Guo-dong LI +2 位作者 Xiao-bo LI Hua-shan YAN Chen LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第7期2128-2138,共11页
The influence of high concentration Zn^(2+) on the floatability of sphalerite in an acidic system was investigated via flotation experiments,zeta potential measurements,contact angle measurements,and X-ray photoelectr... The influence of high concentration Zn^(2+) on the floatability of sphalerite in an acidic system was investigated via flotation experiments,zeta potential measurements,contact angle measurements,and X-ray photoelectron spectroscopy.The results indicated that Zn^(2+) was adsorbed on the sphalerite surface and a Zn-hydroxyl complex was formed at a pH of 4 and a Zn^(2+) concentration of 4×10^(-2) mol/L.The zeta potential increased and the contact angle decreased from 84.80°to 36.48°,strongly inhibiting the floatability of sphalerite.When S^(2−) or Cu^(2+) activator was used alone,sphalerite was not activated after Zn^(2+) was adsorbed,and its contact angle did not change significantly.However,by using a combination of S^(2−) and Cu^(2+) activators,its floatability was realized after Zn^(2+) adsorption.This result was attributed to the removal of the Zn-hydroxyl complex on the surface of sphalerite by S^(2-).After this removal,Cu^(2+) was adsorbed on the sphalerite surface to form a Cu_(2)S·S^(0) hydrophobic film. 展开更多
关键词 acidic system high concentration Zn^(2+) SPHALERITE FLOTATION
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Synthesis of Water Utilization System Using Concentration Interval Analysis Method ( Ⅰ ) Non-Mass-Transfer-Based Operation 被引量:3
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作者 刘永健 袁希钢 罗祎青 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第3期361-368,共8页
A strategy for water and wastewater minimization is developed for continuous water utilization systems involving fixed flowrate(non-mass-transfer-based)operations,based on the fictitious operations that is introduced ... A strategy for water and wastewater minimization is developed for continuous water utilization systems involving fixed flowrate(non-mass-transfer-based)operations,based on the fictitious operations that is introduced to represent the water losing and/or generating operations and a modified concentration interval analysis(MCIA) technique.This strategy is a simple,nongraphical,and noniterative procedure and is suitable for the quick yields of targets and the identification of pinch point location.Moreover,on the basis of the target method,a heuristic-based approach is also presented to generate water utilization networks,which could be demonstrated to be optimum ones. The proposed approaches are illustrated with example problems. 展开更多
关键词 water minimization water utilization network targeting method concentration interval table
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Numerical Study on the Acetylene Concentration in the Hydrogen-Carbon System in a Hydrogen Plasma Torch 被引量:2
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作者 陈龙威 沈洁 +3 位作者 舒兴胜 方世东 张立鹏 孟月东 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第3期321-326,共6页
Effects of the hydrogen/carbon mole ratio and pyrolysis gas pressure on the acetylene concentration in the hydrogen-carbon system in a plasma torch were numerically calculated by using the chemical thermodynamic equil... Effects of the hydrogen/carbon mole ratio and pyrolysis gas pressure on the acetylene concentration in the hydrogen-carbon system in a plasma torch were numerically calculated by using the chemical thermodynamic equilibrium method of Gibbs free energy. The calculated results indicate that the hydrogen concentration and the pyrolysis gas pressure play crucial roles in acetylene formation. Appropriately abundant hydrogen, with a mole ratio of hydrogen to carbon about 1 or 2, and a relatively high pyrolysis gas pressure can enhance the acetylene concentration. In the experiment, a compromised project consisting of an appropriate hydrogen flow rate and a feasible high pyrolysis gas pressure needs to be carried out to increase the acetylene concentration from coal pyrolysis in the hydrogen plasma torch. 展开更多
关键词 acetylene concentration chemical thermodynamic equilibrium Gibbs free energy
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Predictive value of blood concentration of biologics on endoscopic inactivity in inflammatory bowel disease:A systematic review 被引量:1
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作者 Wan-Ting Cao Rong Huang +4 位作者 Ke-Fang Jiang Xue-Hui Qiao Jing-Jing Wang Yi-Hong Fan Yi Xu 《World Journal of Gastroenterology》 SCIE CAS 2021年第9期886-907,共22页
BACKGROUND Although blood concentration of biologics is an important composition of disease management in inflammatory bowel disease(IBD)patients,complexity and uncertainty of biological management encourage many disp... BACKGROUND Although blood concentration of biologics is an important composition of disease management in inflammatory bowel disease(IBD)patients,complexity and uncertainty of biological management encourage many disputes in predicting the outcome of IBD patients through blood concentration of biologics.AIM To verify the predictive value of blood concentration of biologics on endoscopic inactivity in IBD patients under different situations.METHODS We searched PubMed/MEDLINE,Embase,and Web of Science up to May 2020 and identified IBD patients as the research cohort as well as the correlations between blood concentration of biologics and endoscopic inactivity in IBD patients as the research direction.RESULTS A total of 23 articles with 30 clinical studies and 1939 IBD patients were included.The predictive cut-off value of blood concentration of infliximab on mucosal healing should be 2.7-10.6μg/mL in IBD.Blood concentration of infliximab reaching 5.0-12.7μg/mL or more increased the probability of fistula healing/closure in perianal fistulizing Crohn's disease.Blood concentration of adalimumab reaching 7.2-16.2μg/mL or more could predict mucosal healing in IBD.The predictive cut-off value of blood concentration of adalimumab on fistula healing/closure should be 5.9-9.8μg/mL in perianal fistulizing Crohn's disease.Blood concentration of vedolizumab surpassing 25.0μg/mL indicated mucosal healing in ulcerative colitis patients under maintenance therapy and the predictive cut-off value of blood concentration on mucosal healing or endoscopic remission under induction therapy in IBD could be 8.0-28.9μg/mL.CONCLUSION Blood concentration of biologics should not be utilized to predict endoscopic inactivity of IBD independently due to discrepancies in clinical studies,whereas conducting therapeutic drug monitoring intensively contributes to precise therapy. 展开更多
关键词 Inflammatory bowel disease Biological blood concentration Endoscopic inactivity INFLIXIMAB ADALIMUMAB Vedolizumab
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Detection of Learner’s Concentration in Distance Learning System with Multiple Biological Information 被引量:2
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作者 Kimario Nizetha Daniel Eiji Kamioka 《Journal of Computer and Communications》 2017年第4期1-15,共15页
The trend of distance learning education has increased year by year because of the rapid advancement of information and communication technologies. Distance learning system can be regarded as one of ubiquitous computi... The trend of distance learning education has increased year by year because of the rapid advancement of information and communication technologies. Distance learning system can be regarded as one of ubiquitous computing applications since the learners can study anywhere even in mobile environments. However, the instructor cannot know if the learners comprehend the lecture or not since each learner is physically isolated. Therefore, a framework which detects the learners’ concentration condition is required. If a distance learning system obtains the information that many learners are not concentrated on the class due to the incomprehensible lecture style, the instructor can perceive it through the system and change the presentation strategy. This is a context-aware technology which is widely used for ubiquitous computing services. In this paper, an efficient distance learning system, which accurately detects learners’ concentration condition during a class, is proposed. The proposed system uses multiple biological information which are learners’ eye movement metrics, i.e. fixation counts, fixation rate, fixation duration and average saccade length obtained by an eye tracking system. The learners’ concentration condition is classified by using machine learning techniques. The proposed system has performed the detection accuracy of 90.7% when Multilayer Perceptron is used as a classifier. In addition, the effectiveness of the proposed eye metrics has been confirmed. Furthermore, it has been clarified that the fixation duration is the most important eye metric among the four metrics based on the investigation of evaluation experiment. 展开更多
关键词 DISTANCE Learning BIOLOGICAL INFORMATION concentration Eye Tracking Fixation Duration Multilayer PERCEPTRON
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THE EXISTENCE AND CONCENTRATION OF GROUND STATE SOLUTIONS FOR CHERN-SIMONS-SCHR?DINGER SYSTEMS WITH A STEEP WELL POTENTIAL 被引量:1
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作者 Jinlan TAN Yongyong LI Chunlei TANG 《Acta Mathematica Scientia》 SCIE CSCD 2022年第3期1125-1140,共16页
In this paper,we investigate a class of nonlinear Chern-Simons-Schr?dinger systems with a steep well potential.By using variational methods,the mountain pass theorem and Nehari manifold methods,we prove the existence ... In this paper,we investigate a class of nonlinear Chern-Simons-Schr?dinger systems with a steep well potential.By using variational methods,the mountain pass theorem and Nehari manifold methods,we prove the existence of a ground state solution forλ>0 large enough.Furthermore,we verify the asymptotic behavior of ground state solutions asλ→+∞. 展开更多
关键词 Chern-Simons-Schrödinger system steep well potential ground state solution concentration
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Calculating models of mass action concentrations for structural units or ion couples in RbCl-H_2O binary system and RbCl-RbNO_3-H_2O ternary system 被引量:1
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作者 郭汉杰 杨学民 赵伟洁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第6期1112-1120,共9页
Thermodynamic models of calculating mass action concentrations for structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions were developed based on the ion and... Thermodynamic models of calculating mass action concentrations for structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions were developed based on the ion and molecule coexistence theory at 298.15 K.A transformation coefficient is needed to compare the calculated mass action concentration and the reported activity because they are obtained at different standard states and concentration units.The results show that the transformation coefficients between the calculated mass action concentrations and the reported activities of the same structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions change in a very narrow range.The transformed mass action concentrations of structural units or ion couples in RbCl-H2O binary system are in good agreement with the reported activities. The transformed mass action concentrations of RbCl and RbNO3 in RbCl-RbNO3-H2O ternary solution are also in good agreement with the reported activities,aRbCl and 3RbNOa,with different total ionic strengths as 0.01,0.05,0.1,0.5,1.0,1.5,2.0,3.0 and 3.5 mol/kg,respectively.All those results mean the developed thermodynamic model of strong electrolyte aqueous solutions can reflect structural characteristics of RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions and the mass action concentration also strictly follows the mass action law. 展开更多
关键词 mass action concentration ACTIVITY ion and molecule coexistence theory RbCl-H2O RbCl-RbNO3-H2O structural unit ion couple
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