Articles de revues : « Mass flow analysis (MFA) »

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Gao, Jian, Juan Li, Akiber Chufo Wachemo, Hairong Yuan, Xiaoyu Zuo et Xiujin Li. « Mass conversion pathway during anaerobic digestion of wheat straw ». RSC Advances 10, n^o 46 (2020) : 27720–27. http://dx.doi.org/10.1039/d0ra02441d.

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Vingwe, Edward, Edgar Towa et Arne Remmen. « Danish Plastic Mass Flows Analysis ». Sustainability 12, n^o 22 (19 novembre 2020) : 9639. http://dx.doi.org/10.3390/su12229639.

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In this paper, material flows and resource potentials for plastics at a national level in Denmark are mapped using an Environmentally Extended Multiregional Input-Output (EE-MRIO) database. EE-MRIO offers an operative improvement to current and prevalent methods for assessing the industrial and societal metabolism of resources, including plastics. The Exiobase is applied to map (1) the major sources, (2) calculate the total supply, (3) uses of plastics and waste generation, and (4) end of life pathways in order to indicate the potentials of plastics in the circular economy in Denmark with a focus on recycling. Furthermore, it elaborates how and why this method for performing Mass Flow Analysis (MFA) differs from mainstream assessments of material flows and from default uses of national statistical data. Overall, the results are that Denmark has a total supply of ≈551 kilotonnes (Kt) of plastics, out of which ≈522 Kt are used domestically and ≈168 Kt of plastic waste are generated annually. Out of the yearly amount of plastic waste, ≈50% is incinerated and 26% is recycled. These results indicate significant potentials for applying circular economy strategies and identify relevant sectors for closing the plastic loops. However, other initiatives are necessary, such as improvements in product design strategies, in the collection and sorting systems as well as in cross-sectoral collaboration.

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My, Nguyen Tra, Nguyen Viet Anh et Nguyen Hoang Anh. « QUANTIFICATION OF POLLUTANTS MASS AND ENERGY CONSUMPTION AS A TOOL FOR INDUSTRIAL WASTEWATER POLLUTION CONTROL IN STEEL INDUSTRY ». Vietnam Journal of Science and Technology 58, n^o 3A (25 mai 2020) : 148. http://dx.doi.org/10.15625/2525-2518/58/3a/14355.

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Quantification of mass flows in production lines and waste treatment lines, as well as quantification of energy consumption at a factory is always challenges in cleaner production and pollution control decision making. The case study has conducted at a representative steel making complex in Vietnam, simulating the material flows of water and waste streams, and energy balance (EB) for water production and wastewater treatment processes, by using STAN (subSTance flow ANalysis) and SANKEY software, respectively. Input data were taken from secondary data sources, and additional monitoring of wastewater flows at the complex. COD was a selected parameter for material flow analysis (MFA) for evaluation of performance of wastewater treatment plants. Further, two scenarios were given for comparison of water and energy consumptions at existing and upgraded wastewater treatment plants. The results have shown that scenario 2, using disc filter (DF) and ultrafiltration (UF) membrane in combination with ultraviolet (UV) for improving quality of treated wastewater, could allow factory to reuse wastewater for production purposes. At the saved amount of fresh water 10,000 m3/day by reuse of treated wastewater, the saved energy was 1,489.5 kWh/day. The quantitative flows of MFA and EB were clearly presented in STAN and SANKEY diagrams.

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Wongsoonthornchai, Manaporn, et Suphaphat Kwonpongsagoon. « Estimating Mercury Flows through Thermometers and Sphygmomanometers in Healthcare Facilities in Thailand on the Basis of a Material Flow Analysis ». Advanced Materials Research 931-932 (mai 2014) : 629–34. http://dx.doi.org/10.4028/www.scientific.net/amr.931-932.629.

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This paper investigated mercury (Hg) flows and stock through mercury thermometers and sphygmomanometers in Thailand for 2010 using Material Flow Analysis (MFA) based on mass balance principles. All calculations in this study are based on data from hospital surveys and reliable secondary data sources. This study indicates that all thermometers and sphygmomanometers used in Thailand were only imported. Mercury contained in thermometers and sphygmomanometers was about 1,675 kg and 5,375 kg respectively. During the use phase, thermometers can release roughly 70% of Hg into the environment (air and water) while no emissions were emitted from sphygmomanometers. This study also shows that about 20-30% of mercury thermometer and sphygmomanometer waste were disposed of in landfills and incinerators. Hg can be released into air, land, and water at approximately 53%, 35%, and 12% respectively. According to our scenario analysis, it shows that phasing out Hg medical-based devices combined with preventing the breakage and spillage of Hg-thermometers can give higher potential reduction of Hg in Thailand.

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Lok, Yian Yian, John H. Merkin et Ioan Pop. « NON-SYMMETRIC FLOW OVER A STRETCHING/SHRINKING SURFACE WITH MASS TRANSFER ». Mathematical Modelling and Analysis 24, n^o 4 (25 octobre 2019) : 617–34. http://dx.doi.org/10.3846/mma.2019.037.

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The non-symmetric flow over a stretching/shrinking surface in an other-wise quiescent fluid is considered under the assumption that the surface can stretch orshrink in one direction and stretch in a direction perpendicular to this. The problem is reduced to similarity form, being described by two dimensionless parameters, γ the relative stretching/shrinking rate and S characterizing the fluid transfer throughthe boundary. Numerical solutions are obtained for representative values of γ and S, a feature of which are the existence of critical values γc of γ dependent on S, these being determined numerically. Asymptotic forms for large γ and S, for both fluid withdrawal, S > 0 and injection S < 0 are obtained and compared with the corresponding numerical results.

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Pakalka, Saulius, Kęstutis Valančius et Matas Damonskis. « ŠILUMNEŠIO DEBITO ĮTAKOS FAZINIO VIRSMO MEDŽIAGOS VEIKIMUI TYRIMAS / INVESTIGATION OF THE INFLUENCE OF MASS FLOW RATE ON PHASE CHANGE MATERIAL BEHAVIOUR ». Mokslas - Lietuvos ateitis 11 (10 octobre 2019) : 1–5. http://dx.doi.org/10.3846/mla.2019.10578.

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The paper presents an experimental study of the influence of heat transfer fluid (HTF) mass flow rate on phase change materials (PCM) behaviour. The experimental study was performed on a specially designed test bench. Research object – PCM based thermal energy storage unit which consists of a stainless steel tank with dual circuit tube-fin copper heat exchanger. The tank (storage volume) was filled with phase change material RT82. The experiment was carried out using three different mass flow rates of HTF: high – 0.25 kg/s, medium – 0.125 kg/s, low – 0.05 kg/s. The analysis showed that in the case of high and medium mass flow rates the melting/solidification process highly depends on the temperature of inlet HTF. Influence of mass flow rate is higher in the case of low mass flow rate.

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Ahmadi, Mohammad Hossein, Mohammad Ali Afshar, Ali Naseri, Mokhtar Bidi et H. Hadiyanto. « Modeling and PSO optimization of Humidifier-Dehumidifier desalination ». International Journal of Renewable Energy Development 7, n^o 1 (18 février 2018) : 59. http://dx.doi.org/10.14710/ijred.7.1.59-64.

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The aim of this study is modeling a solar-air heater humidification-dehumidification unit with applying particle swarm optimization to find out the maximum gained output ratio with respect to the mass flow rate of water and air entering humidifier, mass flow rate of cooling water entering dehumidifier, width and length of solar air heater and terminal temperature difference (TTD) of dehumidifier representing temperature difference of inlet cooling water and saturated air to dehumidifier as its decision variable. A sensitivity analysis, furthermore, is performed to distinguish the effect of operating parameters including mass flow rate and streams’ temperature. The results showed that the optimum productivity decreases by decreasing the ratio of mass flow rate of water entering humidifier to air ones.Article History: Received: July 12th 2017; Revised: December 15th 2017; Accepted: 2nd February 2018; Available onlineHow to Cite This Article: Afshar, M.A., Naseri, A., Bidi, M., Ahmadi, M.H. and Hadiyanto, H. (2018) Modeling and PSO Optimization of Humidifier-Dehumidifier Desalination. International Journal of Renewable Energy Development, 7(1),59-64.https://doi.org/10.14710/ijred.7.1.59-64

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Gong, Han, et Jin Sheng Shen. « Design of a Novel Hollow-Fiber Membrane Contactor for Carbon Dioxide Absorption ». Advanced Materials Research 777 (septembre 2013) : 33–37. http://dx.doi.org/10.4028/www.scientific.net/amr.777.33.

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In this subject, a new spatial structure of the membrane contactor is explored and designed from analysis of mass transfer process, resistance theory and flow type. Under laboratory conditions, the experiment uses several methods including fluid mechanics, mass transfer process and the analysis of the fluid flow to achieve CO2 absorption function with the new hollow fiber membrane contactor. This new design of device is tested in conditions of two absorption liquids: MEA, DEA; three absorption concentrations: 6L/h, 8L/h, 10L/h; liquid velocity: 1mol/L, 0.5mol/L and air speed: 1L/min, 0.5L/min, to absorb CO2 from the gas mixture to make sure that if it has good properties. Through these experiments, we could see that the new hollow fiber membrane contactor has an increase in absorption efficiency by 10% on average.

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Sarfat, M. S., D. Setyaningsih et Sudirman. « Cumulative energy and cost demand analysis in the synthesis of antistatic bionanocomposites compared with the synthesis of polypropylene ». IOP Conference Series : Earth and Environmental Science 1063, n^o 1 (1 juillet 2022) : 012026. http://dx.doi.org/10.1088/1755-1315/1063/1/012026.

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Abstract This study aims to find the cumulative energy demand (CED) and the cumulative cost demand (CCD) in the synthesis of antistatic bionanocomposites (AS BNC) compared with the synthesis of polypropylene (PP). The CED was identified using SimaPro 9.1.1 software, and the CCD was identified using the material and energy flow analysis (MEFA) method. The analysis results show that the CED required per kg mass of AS BNC pellets was 87.80 MJ, which is lower than the CED required per kg mass of PP pellets (91.19 MJ). This shows that the use of 94.38% of PP, 2% of M-DAG, 2.5% of CNC, 1% of MAPP, 0.02% of MO, 0.03% of AO 1010, and 0.07% of AO 168 in the synthesis of AS BNC can reduction the CED required, with a percentage of CED reduced was 3.71%. The CCD required per kg mass of AS BNC pellets was 68,314.54 IDR, which is higher than the CCD required per kg mass of PP pellets (25,577.27 IDR). The efficiency of energy and natural resources use are necessary to decrease the CED and CCD per kg mass of AS BNC pellets.

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Prasad Thummala, Phanindra, Umran Tezcan Un et Ahmet Ozan Celik. « Investigating the Advantages and Limitations of Modeling Physical Mass Transfer of CO2 on Flat Plate by One Fluid Formulation in OpenFOAM ». Periodica Polytechnica Chemical Engineering 64, n^o 1 (7 janvier 2019) : 124–34. http://dx.doi.org/10.3311/ppch.12291.

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One fluid formulation is an approach used for modeling and analysis of mass transfer between two immiscible phases. In this study we implement and analyze the advantages and limitations of this approach for CO2 physical mass transfer into MEA. The domain is a flat plate and gas liquid flow is counter current. The analysis was carried for operating parameters like liquid phase Reynolds number, MEA mass fraction and the angle of inclination of flat plate. The results clearly show that the model effectively captures the deviation in liquid side mass transfer coefficient due to the surface instabilities and liquid properties which are generally neglected by standard correlations. Also the model shows that the standard Higbie correlation is preferable at low Reynolds number at any angle of inclination. The grid independent studies show that a size of 6.25 µm is required in the interface region for effectively using this approach. The computational resource time at this resolution was found as the only limitation for using this approach and we suggest a procedure to overcome this limitation. The present simulation results can help CFD researchers investigating immiscible gas-liquid mass transfer using OpenFOAM.

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Wang, Kelei, Muhammad Moaaz Ali, Tianxin Guo, Shiwen Su, Xianzhi Chen, Jian Xu et Faxing Chen. « TMT-Based Quantitative Proteomic Analysis Reveals the Response of Tomato (Solanum lycopersicum L.) Seedlings to Ebb-and-Flow Subirrigation ». Agronomy 12, n^o 8 (10 août 2022) : 1880. http://dx.doi.org/10.3390/agronomy12081880.

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Ebb-and-flow subirrigation (EFI) is a water-saving and environmentally friendly irrigation method that can effectively improve water use efficiency and promote plant growth. In this study, we elucidated the effects of ebb-and-flow subirrigation on the protein levels in tomato roots in comparison with top sprinkle irrigation (TSI) and used an integrated approach involving tandem mass tag (TMT) labeling, high-performance liquid chromatography (HPLC) fractionation, and mass-spectrometry (MS)-based analysis. A total of 8510 quantifiable proteins and 513 differentially accumulated proteins (DAPs) were identified, of which the expressions of 283 DAPs were up-regulated, and 230 DAPs were down-regulated in the EFI vs. TSI treatment comparison. According to proteomic data, we performed a systematic bioinformatics analysis of all the identified proteins and DAPs. The DAPs were most significantly associated with the terms ‘metabolic process’, ‘anchored component of membrane’, ‘oxidoreductase activity’, ‘phenylpropanoid biosynthesis’, and ‘biosynthesis of secondary metabolites’ according to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes enrichment (KEGG) analysis. The 272 DAPs were classified into 12 subcellular components according to their subcellular localization. Furthermore, the activities of SOD, POD, CAT, GR, and APX in tomato roots were remarkably increased under EFI, while the MDA content was decreased compared with TSI. Correlation analysis among activities of enzymes and their related DAPs showed that 30 DAPs might be responsible for the regulation of these enzymes. The results showed that ebb-and-flow subirrigation could induce a series of DAPs responses in tomato roots to be adapted to the new mode of water supply.

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Taverna, Elena, Maida De Bortoli, Elisa Maffioli, Cristina Corno, Emilio Ciusani, Silvio Trivulzio, Arnaldo Pinelli, Gabriella Tedeschi, Paola Perego et Italia Bongarzone. « Alterations of RNA Metabolism by Proteomic Analysis of Breast Cancer Cells Exposed to Marycin : A New Optically Active Porphyrin ». Current Molecular Pharmacology 12, n^o 2 (11 avril 2019) : 147–59. http://dx.doi.org/10.2174/1874467212666190204102112.

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Objective: Marycin is a porphyrin-type compound synthetically modified to spontaneously release fluorescence. This study is aimed at understanding possible mechanisms that could account for the antiproliferative effects observed in marycin. A proteomic approach was used to identify molecular effects. The proteome of proliferating MDA-MB-231 breast cancer cells was compared with that of marycin-treated cells. Methods: Label-free proteomic analysis by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was used to reveal changes in protein expression and fluorescence microscopy and flow cytometry were used to detect subcellular organelle dysfunctions. Results: The bioinformatic analysis indicated an enhancement of the expression of proteins remodeling RNA splicing and more in general, of RNA metabolism. Marycin did not localize into the mitochondria and did not produce a dramatic increase of ROS levels in MDA-MB-231 cells. Marycin stained organelles probably peroxisomes. Conclusions: The results could support the possibility that the peroxisomes are involved in cell response to marycin.

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Chen, Pao-Chi, Hsun-Huang Cho, Jyun-Hong Jhuang et Cheng-Hao Ku. « Selection of Mixed Amines in the CO2 Capture Process ». C 7, n^o 1 (24 février 2021) : 25. http://dx.doi.org/10.3390/c7010025.

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In order to select the best mixed amines in the CO2 capture process, the absorption of CO2 in mixed amines was explored at the required concentrations by using monoethanolamine (MEA) as a basic solvent, mixed with diisopropanolamine (DIPA), triethanolamine (TEA), 2-amino-2-methyl-1-propanol (AMP), and piperazine (PZ). Here, a bubble column was used as the scrubber, and a continuous operation was adopted. The Taguchi method was used for the experimental design. The conditional factors included the type of mixed amine (A), the ratio of the mixed amines (B), the liquid feed flow (C), the gas-flow rate (D), and the concentration of mixed amines (E). There were four levels, respectively, and a total of 16 experiments. The absorption efficiency (EF), absorption rate (RA), overall mass transfer coefficient (KGa), and scrubbing factor (ϕ) were used as indicators and were determined in a steady-state by the mass balance and two-film models. According to the Taguchi analysis, the importance of the parameters and the optimum conditions were obtained. In terms of the absorption efficiency (EF), the absorption rate (absorption factor) (RA/ϕ), and the overall mass transfer coefficient (KGa), the order of importance is D > E > A > B > C, D > E > C > B > A, and D > E > C > A > B, respectively, and the optimum conditions are A1B4C4D3E3, A1B3C4D4E2, A4B2C3D4E4, and A1B1C1D4E1. The optimum condition validation results showed that the optimal values of EF, RA, and KGa are 100%, 30.69 × 10−4 mol/s·L, 1.540 l/s, and 0.269, respectively. With regard to the selection of mixed amine, it was found that the mixed amine (MEA + AMP) performed the best in the CO2 capture process.

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Ding, He, Zhiqiang Li, Xin Li, Xiaorui Yang, Jing Zhao, Jing Guo, Wenfa Lu, Hongyu Liu et Jun Wang. « FTO Alleviates CdCl2-Induced Apoptosis and Oxidative Stress via the AKT/Nrf2 Pathway in Bovine Granulosa Cells ». International Journal of Molecular Sciences 23, n^o 9 (29 avril 2022) : 4948. http://dx.doi.org/10.3390/ijms23094948.

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Cadmium (Cd) is a common environmental heavy metal contaminant of reproduction toxicity. Cd accumulation in animals leads to the damage of granulosa cells. However, its mechanism needs to be elucidated. This research found that treating granulosa cells with Cd resulted in reduced cell viability. The flow cytometry results showed that Cd increased the degree of apoptosis and level of superoxide anion (O2−) in granulosa cells. Further analysis showed that Cd treatment resulted in reduced expression levels of nuclear factor erythroid 2-related factor-2 (Nrf2), superoxide dismutase (SOD), catalase (CAT) and NAD(P)H: quinone oxidoreductase 1 (NQO1), and an increased expression level of malondialdehyde (MDA); the expression levels of Bcl-2 associated X (Bax) and caspase-3 increased, whereas that of B-cell lymphoma 2 (Bcl-2) decreased. Changes in m6A methylation-related enzymes were noted with Cd-induced damage to granulosa cells. The results of transcriptome and MeRIP sequencing revealed that the AKT pathway participated in Cd-induced damage in granulosa cells, and the MAX network transcriptional repressor (MNT) may be a potential target gene of fat mass and obesity-associated protein (FTO). FTO and YTH domain family member 2 (YTHDF2) regulated MNT expression through m6A modification. FTO overexpression alleviated Cd-induced apoptosis and oxidative stress through the activation of the AKT/Nrf2 pathway; this process could be reversed using siMNT. Overall, these findings associated m6A with Cd-induced damage to granulosa cells and provided insights into Cd-induced granulosa cell cytotoxicity from a new perspective centered on m6A modification.

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Azizi, Dhiya Durani Sofian, Marlia M. Hanafiah et Kok Sin Woon. « Material Flow Analysis in WEEE Management for Circular Economy : A Content Review on Applications, Limitations, and Future Outlook ». Sustainability 15, n^o 4 (14 février 2023) : 3505. http://dx.doi.org/10.3390/su15043505.

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Recently, the material flow analysis (MFA) of waste from electrical and electronic equipment (WEEE) has attracted much interest from researchers worldwide because of its function as a decision-making tool for moving towards a circular economy and sustainability in WEEE management. However, review studies on the development of MFA in WEEE management studies are still lacking. To fill this gap, 115 MFA studies published in various databases between 2010 and 2022 were analysed to provide a comprehensive overview of current research progress and recommendations for future studies. Three major elements from previous studies were reviewed using content analysis: (i) the trend of publishing in OECD and non-OECD countries over time; (ii) the scope and boundaries of the aspect studied, and the use of MFA in forecasting the generation, flow, and stock of WEEE; and (iii) providing a future outlook for MFA studies based on its limitations. Further analysis has revealed a considerable increase in the number of studies on MFA of WEEE in major OECD nations; however, the number of studies on concentrated areas of WEEE, particularly in non-OECD countries, remains low. Another limitation of MFA research is the scope and boundaries, with very few studies addressing the aspects of uncertainty analysis, circular economy, and life cycle analysis. Due to the increasing number of newly developed methodologies and the absence of thorough evaluation on this study topic, few studies properly utilised the static or dynamic MFA model. Thus, based on the research limitations and gaps discussed, recommendations for future studies are proposed.

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Kajihata, Shuichi, Chikara Furusawa, Fumio Matsuda et Hiroshi Shimizu. « OpenMebius : An Open Source Software for Isotopically Nonstationary13C-Based Metabolic Flux Analysis ». BioMed Research International 2014 (2014) : 1–10. http://dx.doi.org/10.1155/2014/627014.

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Thein vivomeasurement of metabolic flux by13C-based metabolic flux analysis (13C-MFA) provides valuable information regarding cell physiology. Bioinformatics tools have been developed to estimate metabolic flux distributions from the results of tracer isotopic labeling experiments using a13C-labeled carbon source. Metabolic flux is determined by nonlinear fitting of a metabolic model to the isotopic labeling enrichment of intracellular metabolites measured by mass spectrometry. Whereas13C-MFA is conventionally performed under isotopically constant conditions, isotopically nonstationary13C metabolic flux analysis (INST-13C-MFA) has recently been developed for flux analysis of cells with photosynthetic activity and cells at a quasi-steady metabolic state (e.g., primary cells or microorganisms under stationary phase). Here, the development of a novel open source software for INST-13C-MFA on the Windows platform is reported. OpenMebius (Open source software for Metabolic flux analysis) provides the function of autogenerating metabolic models for simulating isotopic labeling enrichment from a user-defined configuration worksheet. Analysis using simulated data demonstrated the applicability of OpenMebius for INST-13C-MFA. Confidence intervals determined by INST-13C-MFA were less than those determined by conventional methods, indicating the potential of INST-13C-MFA for precise metabolic flux analysis. OpenMebius is the open source software for the general application of INST-13C-MFA.

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Duque, Luis, Antonio Molinero, Juan Carlos Oller, José Miguel Barcala, M. Antonia Folgado et Antonio M. Chaparro. « Analysis of Hydrogen Feeding to the Anode of a PEMFC By a Transport Impedance Technique ». ECS Meeting Abstracts MA2022-02, n^o 39 (9 octobre 2022) : 1406. http://dx.doi.org/10.1149/ma2022-02391406mtgabs.

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Hydrogen feeding to the catalyst layer of the anode of a proton-exchange membrane fuel cell (PEMFC) must be fast enough to allow for high power response and avoid starvation events. However, there are limitations to the flow rate posed by the anode architecture (manifold, inlet port, flow field), and the gas diffusion layer (GDL). Within the GDL, hydrogen transport conditions may change in-operando as a result of water generation and saturation of pores. Delays in hydrogen feeding will give rise to a decrease in power response, and transitory sub-stoichiometric conditions, that may damage the electrode and decrease fuel cell durability. Therefore, it is of high interest to probe hydrogen feeding conditions when designing new anode architectures, and during operation of the fuel cell. Mass transport conditions in the fuel cell and electrochemical systems can be probed by techniques based on the impedance concept [1,2,3]. Among them, one recently applied in our group is the current modulated H2 flow-rate spectroscopy (CH2S), which provides the transfer function H [4,5]: H(j w) = nF QH2 / I (Eq. 1) Where QH2 is the modulated hydrogen inlet flow, I the modulated cell current, n(=2) the electron exchanges per H2 molecule, and F(=96485 C mol-1) the Faraday constant. A typical response in a PEMFC with dead-end anode is shown in Fig. 1. The H function normally presents two or more semicircles in Nyquist plots, extending in the real axis from H'=0 to H'=1 (stoichiometric modulation). The high frequency semicircle is normally ascribed to the set-up time response limitation, mostly the flow meter. At higher frequencies, the H function shows characteristics of the time response of hydrogen flow up to the anodic catalyst layer. In this communication, the CH2S technique is applied in conventional single cells and in passive portable feeding PEMFCs. Some properties of H2 transport path towards the anodic catalyst layer are analyzed, like conduits length, inlet port type, anode flow field, liquid water contents, hydrogen stoichiometry, and anode hydrophobicity. Acknowledgement: The work is partially financed by the ELHYPORT project (PID2019−110896RB-I00), Spanish Ministry of Science and Innovation. [1] C. Deslouis, I. Epelboin, C. Gabrielli, P.S.-R. Fanchine, B. Tribollet, Relationship between the electrochemical impedance and the electrohydrodynamical impedances measured using a rotating disc electrode, J. Electroanal. Chem. Interfacial Electrochem. 107 (1980) 193–195. [2] A. Sorrentino, T. Vidakovic-Koch, R. Hanke-Rauschenbach, K. Sundmacher, Concentration-alternating frequency response: A new method for studying polymer electrolyte membrane fuel cell dynamics, Electrochim. Acta. 243 (2017) 53–64. [3] D. Grübl, J. Janek, W.G. Bessler, Electrochemical Pressure Impedance Spectroscopy (EPIS) as Diagnostic Method for Electrochemical Cells with Gaseous Reactants: A Model-Based Analysis, J. Electrochem. Soc. 163 (2016) A599–A610. [4] M.A. Folgado, H. Moreno, A. Molinero, J.C. Oller, J.M. Barcala, A.M. Chaparro Hydrogen Transport Impedance for the Study of Anodes in PEMFCs, European Fuel Cell Forum 2021, A0704 (Extended Abstract). Lucerne (Switzerland). [5] A. Molinero, J.C. Oller, J.M. Barcala, H. Moreno, M.A. Folgado, A.M. Chaparro, Experimental Set-Up for Transport Studies of Anodes in PEMFCs. European Fuel Cell Forum 2021, B0207 (Extended Abstract). Lucerne (Switzerland). Fig. 1. Nyquist plot of the H function according to Eq. 1, for a PEMFC cell with commercial electrodes (Pt/C 0.3mg·cm-2) and Nafion 212NR membrane, working with hydrogen feeding in dead-end mode, and air feeding in cathode. a) Full signal; b) Low frequency detail. Numbers are modulation frequencies. Figure 1

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Terekhanova, T. A., B. Helm, J. Traenckner et P. Krebs. « IWRM decision support with material flow analysis : consideration of urban system input ». Water Science and Technology 66, n^o 11 (1 décembre 2012) : 2432–38. http://dx.doi.org/10.2166/wst.2012.470.

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A review of material flow analysis (MFA) tools, comparison of case studies and analysis of approximately 20 MFA tools (static, semi-empirical models) are performed. The evaluation of the quantification procedures revealed several deficits in the approaches. The following principal complications for a reliable quantification of inputs from the urban water system are identified: (1) frequently insufficient data for urban system model validation (e.g. combined sewer overflow (CSO) discharges); (2) the necessity for additionally quantifying diffuse sources in order to verify modelling results at basin scale, where both input pathways occur, and (3) the contradictions arising when describing the highly dynamic urban system with the help of static MFA models. However, a wise selection of appropriate calculation procedures with regard to the concrete systems characteristics and available data can minimize the model deviations significantly. Criteria and suggestions for designing adapted quantification procedures are given.

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Yasutake, Masahiro, Zhiyun Noda, Yuya Tachikawa, Stephen Matthew Lyth, Junko Matsuda, Masamichi Nishihara, Kohei Ito, Akari Hayashi et Kazunari Sasaki. « Temperature Distribution Analysis of PEM Electrolyzer in High Current Density Operation By Numerical Simulation ». ECS Meeting Abstracts MA2022-02, n^o 44 (9 octobre 2022) : 1639. http://dx.doi.org/10.1149/ma2022-02441639mtgabs.

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Introduction High current density operation of water electrolysis enables mass production of hydrogen in a small system. With respect to high current density operation, alkaline water electrolysis, which are currently widely used for hydrogen production, has material-related limitations like ohmic resistance. However, polymer electrolyte membrane water electrolysis (PEMWE) has less limitations for higher current density operation, so that high current density operation of PEMWE is an advantageous feature compared with other water electrolysis technologies. High current density operation also leads to lower capital cost by reducing electrode area. A large amount of heat is however generated in high current density operation1, which could lead to nonuniform temperature distribution in the cell and therefore understanding the internal cell temperature distribution is important. Some researchers studied internal cell temperature distribution by numerical simulation2 , 3, but, to the best of our knowledge, no study has been done so far in a current density range of up to 10 A cm-2. The aim of this study is, by numerical analysis, to clarify internal cell temperature distribution around 10 A cm-2 which is the operating range of future PEM water electrolysis.4 Experimental A two-dimensional computational fluid dynamics (CFD) model for a 1 cm×1 cm PEM electrolysis cell consisting of MEA, GDL and flow channel was developed for numerical analysis of I-V characteristics and cell temperature distribution. CFD software COMSOL Multiphysics ver. 6.0 was used for the simulation. The cell temperature was fixed at 80 oC and the flow rate of water was set to be 5 to 15 ml min-1. Water was supplied from left hand side to the anode, and from right hand side to the cathode, as shown in Fig 1(b). The thickness of electrolyte membrane was set to be 51, 127, and 183 μm simulating Nafion 212, 115, and 117. I-V characteristics were analyzed by simulating the potential scan from 1.3 V to 2.5 V. The cell temperature distribution was analyzed in a steady state. The essential material property parameters for the calculations were procured from literature survey. Mass transport resistance, not yet understood sufficiently,5 was not considered in this calculation. The relation between current density and internal cell temperature distribution was investigated. Results and discussion Figure 1 shows I-V characteristics of a PEMWE cell simulated by following operating conditions: electrolyte membrane thickness of 51 μm; the flow rate of the supply water of 5 ml min-1, and the cell voltage of 2.5 V (current density of 11.8 A cm-2) in a steady state. Figure 1(a) shows linear I-V characteristics consisting predominantly ohmic overpotential in high current density region due to ignored mass transport resistance in this calculation. The cell temperature distribution in Fig. 1(b) shows that the cell temperature increased towards the outlet of water supply on the anode side and that temperature difference of approximately 20 K was generated between the inlet and outlet of water supply on the anode side. Temperature difference was suppressed by increasing the flow rate of water supplied. This result suggests the importance of appropriate rate of water supply for uniform cell temperature distribution especially in high current density operation. References M. Suermann, T. J. Schmidt, and F. N. Büchi, Electrochim. Acta, 211, 989–997 (2016). S. Toghyani, E. Afshari, E. Baniasadi, S. A. Atyabi, and G. F. Naterer, Energy, 152, 237–246 (2018). M. Upadhyay, A. Kim, S. S. Paramanantham, H. Kim, D. Lim, S. Lee, S. Moon, and H. Lim, Appl. Energy, 306, 118016 (2022). A. Villagra and P. Millet, Int. J. Hydrogen Energy, 44, 9708–9717 (2019). M. Suermann, T. J. Schmidt, and F. N. Buchi, ECS Trans., 69, 1141–1148 (2015). Figure 1

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Rimantho, Dino, Nur Yulianti Hidayah, Agung Saputra, Averina Chandra, Ananda Nurul Rizkiya, Gina Nashifah, Pipit Fitriyani et Devi Milenia Putri Wesha. « Material Flow Analysis for Assessing the Sustainability Solid Waste Management Strategy ». International Journal of Sustainable Development and Planning 17, n^o 7 (30 novembre 2022) : 2271–78. http://dx.doi.org/10.18280/ijsdp.170728.

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With increasing income levels and accelerating consumption, municipal solid waste management (MSW) has become important in developing countries. This study intends to use material flow analysis (MFA) to assess the waste management strategy in Bogor-Indonesia. Moreover, this study also determines the extent of the waste flow path and provides suggestions for improvement. Waste volume data is carried out directly for ten days, referring to Indonesian Standards (SNI 3242: 2008 and SNI 19-3964-1994) related to waste management in settlements in Indonesia. Furthermore, the waste generation data were analyzed by applying the MFA Method. Data processing using STAN (Substance Flow Analysis Version 3) software makes Material Flow Analysis (MFA) images. The data shows that the waste generated is 20 kg to 140 kg per day. The existing conditions indicate that the waste is burned or disposed of in municipal landfills. The proposed waste management strategy model reveals 30.66 tons/year of inorganic waste that can be recovered through recycling and about 20.13 tons/year. The strategy that can be done is to establish a waste bank that applies Maggot BSF cultivation to recycle the organic waste produced. Decision-makers need future studies of material flows to be able to plan for changes in waste flows.

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Zeituni, Amir, Elizabeth Scisci, William McCaig, David Thanassi et Christopher Cutler. « DC-SIGN targeting carbohydrate moieties identified on 67 kDa mfa-1 fimbriae of mucosal pathogen Porphyromonas gingivalis (42.7) ». Journal of Immunology 184, n^o 1_Supplement (1 avril 2010) : 42.7. http://dx.doi.org/10.4049/jimmunol.184.supp.42.7.

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Abstract We recently reported that the oral mucosal pathogen Porphyromonas gingivalis targets the C- type lectin receptor DC-SIGN for invasion and persistence within human monocyte-derived dendritic cells (DCs). The DCs respond by inducing an immunosuppressive and Th2-biased CD4+ T cell response (Zeituni et al 2009); moreover, DC invasion and immunosuppression are dependent upon expression of the 67 kDa mfa-1 fimbriae by P. gingivalis . We have now purified mfa-1 by ion exchange chromatography and sequenced it by tandem mass spectrometry (MS/MS), confirming its identify and revealing two putative N-glycosylation motifs as well as numerous O-glycosylation motifs. We further show mfa-1 is glycosylated by ProQ staining. Further monosaccharide analysis by gas chromatography-mass spectrometry (GC-MS) confirmed that mfa-1 contains fucose (1.35 nmol/mg) mannose (2.68 nmol/mg), N-acetylglucosamine (2.27 nmol/mg) and N-acetylgalactosamine (0.652 nmol/mg). Analysis by transmission electron microscopy reveals mfa-1 form oligomeric strains approximately 200 nm in length, which could be involved in targeting/ cross-linking DC-SIGN. These findings shed further light on mechanisms of invasion and immunosuppression by this unique mucosal pathogen.

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Qiu, Cheng, Wei Yi Sun, Chao Long Wang et Shi Jun Su. « Materials Flow Analysis on the System of Flue Gas Desulfurization and Denitration with Pyrolusite Slurry ». Advanced Materials Research 383-390 (novembre 2011) : 3162–68. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.3162.

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Circular economy promotes the establishment of recycling-oriented society and recycling-based businesses. Circular economy is characterized by eco-efficiency improvement and materials recycle, furthermore, it also has provided a practical and feasible way for the sustainable development of human society. Materials flow analysis (MFA) has provided a new and simple way to study the development of circular economy. MFA is based on materials inputs and outputs, and then creates materials inputs and outputs account to manage materials flow. The process using pyrolusite for FGD produces manganese, high-purified manganese carbonates and slag used for cement production as byproducts. Electrolytic manganese production process, high-sulfur coal combustion process and cement production process are studied in the research. Materials flows of these processes are studied. The new production patterns are compared with the traditional ones basing on MFA. The results show that these processes are more environment-friendly and resource-saving in the comparison. To evaluate the circular economy efficiency of the complementary system, the evaluation index system of the circular economy construction is created.

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Turner, Andrew D., Sophie Tarnovius, Robert G. Hatfield, Mickael Teixeira Alves, Maggie Broadwater, Frances Van Dolah, Ernesto Garcia-Mendoza et al. « Application of Six Detection Methods for Analysis of Paralytic Shellfish Toxins in Shellfish from Four Regions within Latin America ». Marine Drugs 18, n^o 12 (3 décembre 2020) : 616. http://dx.doi.org/10.3390/md18120616.

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With the move away from use of mouse bioassay (MBA) to test bivalve mollusc shellfish for paralytic shellfish poisoning (PSP) toxins, countries around the world are having to adopt non-animal-based alternatives that fulfil ethical and legal requirements. Various assays have been developed which have been subjected to single-laboratory and multi-laboratory validation studies, gaining acceptance as official methods of analysis and approval for use in some countries as official control testing methods. The majority of validation studies conducted to date do not, however, incorporate shellfish species sourced from Latin America. Consequently, this study sought to investigate the performance of five alternative PSP testing methods together with the MBA, comparing the PSP toxin data generated both qualitatively and quantitatively. The methods included a receptor binding assay (RBA), two liquid chromatography with fluorescence detection (LC-FLD) methods including both pre-column and post-column oxidation, liquid chromatography with tandem mass spectrometry (LC-MS/MS) and a commercial lateral flow assay (LFA) from Scotia. A total of three hundred and forty-nine shellfish samples from Argentina, Mexico, Chile and Uruguay were assessed. For the majority of samples, qualitative results compared well between methods. Good statistical correlations were demonstrated between the majority of quantitative results, with a notably excellent correlation between the current EU reference method using pre-column oxidation LC-FLD and LC-MS/MS. The LFA showed great potential for qualitative determination of PSP toxins, although the findings of high numbers of false-positive results and two false negatives highlighted that some caution is still needed when interpreting results. This study demonstrated that effective replacement methods are available for countries that no longer wish to use the MBA, but highlighted the importance of comparing toxin data from the replacement method using local shellfish species of concern before implementing new methods in official control testing programs.

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Prakash, J. Ravi, et K. Kesava Rao. « Steady compressible flow of cohesionless granular materials through a wedge-shaped bunker ». Journal of Fluid Mechanics 225 (avril 1991) : 21–80. http://dx.doi.org/10.1017/s0022112091001969.

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A continuum model based on the critical-state theory of soil mechanics is used to generate stress, density, and velocity profiles, and to compute discharge rates for the flow of granular material in a mass flow bunker. The bin–hopper transition region is idealized as a shock across which all the variables change discontinuously. Comparison with the work of Michalowski (1987) shows that his experimentally determined rupture layer lies between his prediction and that of the present theory. However, it resembles the former more closely. The conventional condition involving a traction-free surface at the hopper exit is abandoned in favour of an exit shock below which the material falls vertically with zero frictional stress. The basic equations, which are not classifiable under any of the standard types, require excessive computational time. This problem is alleviated by the introduction of the Mohr–Coulomb approximation (MCA). The stress, density, and velocity profiles obtained by integration of the MCA converge to asymptotic fields on moving down the hopper. Expressions for these fields are derived by a perturbation method. Computational difficulties are encountered for bunkers with wall angles θw [ges ] 15° these are overcome by altering the initial conditions. Predicted discharge rates lie significantly below the measured values of Nguyen et al. (1980), ranging from 38% at θw = 15° to 59% at θw = 32°. The poor prediction appears to be largely due to the exit condition used here. Paradoxically, incompressible discharge rates lie closer to the measured values. An approximate semi-analytical expression for the discharge rate is obtained, which predicts values within 9% of the exact (numerical) ones in the compressible case, and 11% in the incompressible case. The approximate analysis also suggests that inclusion of density variation decreases the discharge rate. This is borne out by the exact (numerical) results – for the parameter values investigated, the compressible discharge rate is about 10% lower than the incompressible value. A preliminary comparison of the predicted density profiles with the measurements of Fickie et al. (1989) shows that the material within the hopper dilates more strongly than predicted. Surprisingly, just below the exit slot, there is good agreement between theory and experiment.

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GOWER, C. M., A. F. GABRIELLI, M. SACKO, R. DEMBELÉ, R. GOLAN, A. M. EMERY, D. ROLLINSON et J. P. WEBSTER. « Population genetics of Schistosoma haematobium : development of novel microsatellite markers and their application to schistosomiasis control in Mali ». Parasitology 138, n^o 8 (17 juin 2011) : 978–94. http://dx.doi.org/10.1017/s0031182011000722.

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SUMMARYThe recent implementation of mass drug administration (MDA) for control of uro-genital schistosomiasis has identified an urgent need for molecular markers to both directly monitor the impact of MDA, for example to distinguish re-infections from uncleared infections, as well as understand aspects of parasite reproduction and gene flow which might predict evolutionary change, such as the development and spread of drug resistance. We report the development of a novel microsatellite tool-kit allowing, for the first time, robust genetic analysis of individual S. haematobium larvae collected directly from infected human hosts. We genotyped the parasite populations of 47 children from 2 schools in the Ségou region of Mali, the first microsatellite study of this highly neglected parasite. There was only limited evidence of population subdivision between individual children or between the two schools, suggesting that few barriers to gene flow exist in this population. Complex relationships between parasite reproductive success, infection intensity and host age and gender were identified. Older children and boys harboured more diverse infections, as measured by the number of unique adult genotypes present. Individual parasite genotypes had variable reproductive success both across hosts, a pre-requisite for evolutionary selection, and, phenotypically, in hosts of different ages and genders. These data serve as a baseline against which to measure the effect of treatment on parasite population genetics in this region of Mali, and the tools developed are suitable to further investigate this important pathogen, and its close relatives, throughout their range.

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Wang, Sheng, Jing Dai et Meirong Su. « Material Flow Analysis of Fossil Fuels in China during 2000–2010 ». Scientific World Journal 2012 (2012) : 1–8. http://dx.doi.org/10.1100/2012/625828.

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Since the relationship between the supply and demand of fossil fuels is on edge in the long run, the contradiction between the economic growth and limited resources will hinder the sustainable development of the Chinese society. This paper aims to analyze the input of fossil fuels in China during 2000–2010 via the material flow analysis (MFA) that takes hidden flows into account. With coal, oil, and natural gas quantified by MFA, three indexes, consumption and supply ratio (C/S ratio), resource consumption intensity (RCI), and fossil fuels productivity (FFP), are proposed to reflect the interactions between population, GDP, and fossil fuels. The results indicated that in the past 11 years, China’s requirement for fossil fuels has been increasing continuously because of the growing mine productivity in domestic areas, which also leads to a single energy consumption structure as well as excessive dependence on the domestic exploitation. It is advisable to control the fossil fuels consumption by energy recycling and new energy facilities’ popularization in order to lead a sustainable access to nonrenewable resources and decrease the soaring carbon emissions.

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Qin, Lu, He, Qi, Li et Hu. « Effect of Silane Treatment on Mechanical Properties of Polyurethane/Mesoscopic Fly Ash Composites ». Polymers 11, n^o 4 (24 avril 2019) : 741. http://dx.doi.org/10.3390/polym11040741.

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In view of the accidents such as rock mass breakage, roof fall and coal slide in coal mines, polyurethane/mesoscopic fly ash (PU/MFA) reinforcement materials were produced from polymethylene polyphenylene isocyanate (PAPI), the polyether polyol, flame retardant, and MFA using stannous octanate as a catalyst. 3-Glycidoxypropyltrimethoxysilane (GPTMS) was grafted on MFA surface, aiming to improve the mechanical properties of PU/MFA composites. The analyses of infrared spectroscopy and compression resistance reveal that the GPTMS can be successfully attached to the surface of MFA, and the optimum modification dosage of GPTMS to MFA is 2.5 wt % (weight percent). On this basis, the effect of GPTMS on the mechanical properties of PU/MFA reinforcement materials during the curing process was systematically investigated through a compression test, a fracture toughness test, a three-point bending test, a bond property test, and a dynamic mechanics analysis. The results show that the compression property, fracture toughness, maximum flexural strength, and bond strength of PU/MFA composites increase by 21.6%, 10.1%, 8.8%, and 19.3%, respectively, compared with the values before the modification. Furthermore, the analyses of scanning electron microscope and dynamic mechanics suggest that the coupling agent GPTMS can successfully improve the mechanical properties of PU/MFA composites because it eliminates the stress concentration and exerts a positive effect on the crosslink density and hardness of PU/MFA composites.

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Lugar, Daniel J., et Ganesh Sriram. « Isotope-assisted metabolic flux analysis as an equality-constrained nonlinear program for improved scalability and robustness ». PLOS Computational Biology 18, n^o 3 (24 mars 2022) : e1009831. http://dx.doi.org/10.1371/journal.pcbi.1009831.

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Stable isotope-assisted metabolic flux analysis (MFA) is a powerful method to estimate carbon flow and partitioning in metabolic networks. At its core, MFA is a parameter estimation problem wherein the fluxes and metabolite pool sizes are model parameters that are estimated, via optimization, to account for measurements of steady-state or isotopically-nonstationary isotope labeling patterns. As MFA problems advance in scale, they require efficient computational methods for fast and robust convergence. The structure of the MFA problem enables it to be cast as an equality-constrained nonlinear program (NLP), where the equality constraints are constructed from the MFA model equations, and the objective function is defined as the sum of squared residuals (SSR) between the model predictions and a set of labeling measurements. This NLP can be solved by using an algebraic modeling language (AML) that offers state-of-the-art optimization solvers for robust parameter estimation and superior scalability to large networks. When implemented in this manner, the optimization is performed with no distinction between state variables and model parameters. During each iteration of such an optimization, the system state is updated instead of being calculated explicitly from scratch, and this occurs concurrently with improvement in the model parameter estimates. This optimization approach starkly contrasts with traditional “shooting” methods where the state variables and model parameters are kept distinct and the system state is computed afresh during each iteration of a stepwise optimization. Our NLP formulation uses the MFA modeling framework of Wiechert et al. [1], which is amenable to incorporation of the model equations into an NLP. The NLP constraints consist of balances on either elementary metabolite units (EMUs) or cumomers. In this formulation, both the steady-state and isotopically-nonstationary MFA (inst-MFA) problems may be solved as an NLP. For the inst-MFA case, the ordinary differential equation (ODE) system describing the labeling dynamics is transcribed into a system of algebraic constraints for the NLP using collocation. This large-scale NLP may be solved efficiently using an NLP solver implemented on an AML. In our implementation, we used the reduced gradient solver CONOPT, implemented in the General Algebraic Modeling System (GAMS). The NLP framework is particularly advantageous for inst-MFA, scaling well to large networks with many free parameters, and having more robust convergence properties compared to the shooting methods that compute the system state and sensitivities at each iteration. Additionally, this NLP approach supports the use of tandem-MS data for both steady-state and inst-MFA when the cumomer framework is used. We assembled a software, eiFlux, written in Python and GAMS that uses the NLP approach and supports both steady-state and inst-MFA. We demonstrate the effectiveness of the NLP formulation on several examples, including a genome-scale inst-MFA model, to highlight the scalability and robustness of this approach. In addition to typical inst-MFA applications, we expect that this framework and our associated software, eiFlux, will be particularly useful for applying inst-MFA to complex MFA models, such as those developed for eukaryotes (e.g. algae) and co-cultures with multiple cell types.

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Bai, Mengyu, et Daoji Li. « Quantity of plastic waste input into the ocean from China based on a material flow analysis model ». Anthropocene Coasts 3, n^o 1 (1 janvier 2020) : 1–5. http://dx.doi.org/10.1139/anc-2018-0028.

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Marine plastic waste has been an important global environmental issue in recent years, and quantifying the amount of global marine plastic waste input is vital for control and mitigation. However, determining an accurate quantity of oceanic plastics is challenging because comprehensive monitoring data are difficult to obtain on national and global scales. To understand the contribution of China in global marine plastic waste input, we used a material flow analysis (MFA) method, which is included in lifecycle assessment and combines statistical data from China’s official statistics, reports, and NPO (nonprofit organization) to establish an MFA model. The model assesses the lifecycle of plastics, which starts with primary plastic, passes the stage of plastic product, and eventually becomes plastic waste. With the MFA model, the annual amount of plastic waste entering the ocean from China from 2011 to 2020 can be calculated. In 2011, 0.65 million tonnes of plastic waste entered the ocean from China, and the quantity rose slowly until 2016. A rapid decline appeared in 2018 because of China’s governmental managements and the quantity will continue to decrease until 2020. Our results indicate the amount of oceanic plastics has a strong correlation with government control measures.

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Zhi, Jing, Ze Qiang Fu, Peng Shen et Bao Gao. « Analysis of Material Metabolism for Ningdong Energy(Coal) and Coal Chemical Base ». Applied Mechanics and Materials 71-78 (juillet 2011) : 2132–35. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.2132.

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Material flow analysis (MFA) has become a useful tool fo to analyze the metabolism of social systems. This paper proposes to use the indicators derived from MFA, complemented with water and energy indicators, to analyze the efficiency and the materialization ranks of Ningdong energy(coal) and coal chemical base (China). The companies in the base have many opportunities to improve on these aspects and the indicators can measure and reflect their evolution. In addition, the results show the importance that some flows such as water inputs which often are omitted, can have in some study cases.

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Jain, K. P., J. F. J. Pruyn et J. J. Hopman. « Material flow analysis (MFA) as a tool to improve ship recycling ». Ocean Engineering 130 (janvier 2017) : 674–83. http://dx.doi.org/10.1016/j.oceaneng.2016.11.036.

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Harazin, Piroska, Gréta Judit Dezső et Andrea Karcagi-Kováts. « Anyagáramok és anyagállományok egy debreceni szolgáltató vállalatnál ». International Journal of Engineering and Management Sciences 4, n^o 4 (12 décembre 2019) : 313–21. http://dx.doi.org/10.21791/ijems.2019.4.35.

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Az elmúlt 25 évben, egy sor kutatóintézet számos neves tudósa kidolgozott egy új kutatási irányzatot, egy új módszertani családot, az anyagáram elemzést (MFA – Material Flow Analysis). Az MFA jelentőségét az emberiség által létrehozott, gerjesztett anyagáramok mértéke adja. Az MFA növekvő sikerének alapjait egy gyökeresen új, interdiszciplináris, a természet- és társadalomtudományok (ökológia, termodinamika és közgazdaságtan) együttműködését igénylő látásmód adja, azaz nem csak a termelés anyaghatékonyságának és a gerjesztett környezetterhelés vizsgálatának hatásos eszköze, hanem segítséget nyújt a szükséges technológiai innováció irányainak feltárásához, valamint a vizsgált rendszer stratégiai anyagigényei ellátásbiztonságának az elemzéséhez is. Cikkünkben vállalati szintű elemzést végzünk, egy debreceni szolgáltató vállalat 2018-as évre vonatkozó input és outputoldali anyagáramait és anyagállományait elemezzük az MFA módszerével. Az MFA indikátorok naturális dimenzióban ragadják meg a környezetterhelést, azaz tömegben, energiában vagy földterületben mérnek, ennek megfelelően kilogrammban, vagy tonnában mérve mutatjuk be a cég kiinduló anyagállományait és az abban bekövetkezett változásokat, illetve az anyaginputokat.

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Kleijn, Roelco J., Wouter A. van Winden, Cor Ras, Walter M. van Gulik, Dick Schipper et Joseph J. Heijnen. « 13C-Labeled Gluconate Tracing as a Direct and Accurate Method for Determining the Pentose Phosphate Pathway Split Ratio in Penicillium chrysogenum ». Applied and Environmental Microbiology 72, n^o 7 (juillet 2006) : 4743–54. http://dx.doi.org/10.1128/aem.02955-05.

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ABSTRACT In this study we developed a new method for accurately determining the pentose phosphate pathway (PPP) split ratio, an important metabolic parameter in the primary metabolism of a cell. This method is based on simultaneous feeding of unlabeled glucose and trace amounts of [U-13C]gluconate, followed by measurement of the mass isotopomers of the intracellular metabolites surrounding the 6-phosphogluconate node. The gluconate tracer method was used with a penicillin G-producing chemostat culture of the filamentous fungus Penicillium chrysogenum. For comparison, a 13C-labeling-based metabolic flux analysis (MFA) was performed for glycolysis and the PPP of P. chrysogenum. For the first time mass isotopomer measurements of 13C-labeled primary metabolites are reported for P. chrysogenum and used for a 13C-based MFA. Estimation of the PPP split ratio of P. chrysogenum at a growth rate of 0.02 h−1 yielded comparable values for the gluconate tracer method and the 13C-based MFA method, 51.8% and 51.1%, respectively. A sensitivity analysis of the estimated PPP split ratios showed that the 95% confidence interval was almost threefold smaller for the gluconate tracer method than for the 13C-based MFA method (40.0 to 63.5% and 46.0 to 56.5%, respectively). From these results we concluded that the gluconate tracer method permits accurate determination of the PPP split ratio but provides no information about the remaining cellular metabolism, while the 13C-based MFA method permits estimation of multiple fluxes but provides a less accurate estimate of the PPP split ratio.

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Mainasara, Muhammad Murtala, Mohd Fadzelly Abu Bakar, Abdah Md Akim, Alona C. Linatoc, Fazleen Izzany Abu Bakar et Yazan K. H. Ranneh. « Secondary Metabolites, Antioxidant, and Antiproliferative Activities of Dioscorea bulbifera Leaf Collected from Endau Rompin, Johor, Malaysia ». Evidence-Based Complementary and Alternative Medicine 2021 (11 janvier 2021) : 1–10. http://dx.doi.org/10.1155/2021/8826986.

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Breast cancer is among the most commonly diagnosed cancer and the leading cause of cancer-related death among women globally. Malaysia is a country that is rich in medicinal plant species. Hence, this research aims to explore the secondary metabolites, antioxidant, and antiproliferative activities of Dioscorea bulbifera leaf collected from Endau Rompin, Johor, Malaysia. Antioxidant activity was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) assays, while the cytotoxicity of D. bulbifera on MDA-MB-231 and MCF-7 breast cancer cell lines was tested using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Cell cycle analysis and apoptosis were assessed using flow cytometry analysis. Phytochemical profiling was conducted using gas chromatography-mass spectrometry (GC-MS). Results showed that methanol extract had the highest antioxidant activity in DPPH, FRAP, and ABTS assays, followed by ethyl acetate and hexane extracts. D. bulbifera tested against MDA-MB-231 and MCF-7 cell lines showed a pronounced cytotoxic effect with IC50 values of 8.96 μg/mL, 6.88 μg/mL, and 3.27 μg/mL in MCF-7 and 14.29 μg/mL, 11.86 μg/mL, and 7.23 μg/mL in MDA-MB-231, respectively. Cell cycle analysis also indicated that D. bulbifera prompted apoptosis at various stages, and a significant decrease in viable cells was detected within 24 h and substantially improved after 48 h and 72 h of treatment. Phytochemical profiling of methanol extract revealed the presence of 39 metabolites such as acetic acid, n-hexadecanoic acid, acetin, hexadecanoate, 7-tetradecenal, phytol, octadecanoic acid, cholesterol, palmitic acid, and linolenate. Hence, these findings concluded that D. bulbifera extract has promising anticancer and natural antioxidant agents. However, further study is needed to isolate the bioactive compounds and validate the effectiveness of this extract in the In in vivo model.

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Rimantho, Dino, Erliza Noor, Eriyatno Eriyatno et Hefni Effendi. « Penilaian aliran limbah elektronika di DKI Jakarta menggunakan Material Flow Analysis (MFA) ». Jurnal Ilmu Lingkungan 17, n^o 1 (29 mai 2019) : 120. http://dx.doi.org/10.14710/jil.17.1.120-129.

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Electronic equipment is produced to meet human needs, so this will also have a significant impact on increasing the rate of e-waste generation in landfills in almost all countries. One of the environmental pollution issues that are of concern throughout the world is the management of e-waste (e-waste). This is due to the rapid increase in the use of electronic products. Thus, the existence of electrical and electronic equipment becomes shorter and becomes obsolete. The absence of information related to the volume of e-waste generation and material flow is one of the problems of the Indonesian government in managing e-waste. Therefore, the purpose of this paper is to calculate e-waste and analyze material flow. The method used in this study is Material Flow Analysis (MFA). Furthermore, a survey of household and informal sector respondents was used. The questionnaire adopted from UNEP was modified and distributed to 400 households and 54 informal sectors in DKI Jakarta. The results show the total rate of generation of e-waste produced aaproximately 7713.42013 kg/year. Furthermore, it is necessary to develop several strategies in order to avoid negative impact. This research can be information in filling the data limitations and management of sustainable e-waste in DKI Jakarta.

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Amicarelli, Vera, Christian Bux et Giovanni Lagioia. « How to measure food loss and waste ? A material flow analysis application ». British Food Journal 123, n^o 1 (1 juillet 2020) : 67–85. http://dx.doi.org/10.1108/bfj-03-2020-0241.

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PurposeThe purpose of this paper is to measure food loss and waste by material flow analysis (MFA) tool. Applying this methodology, the authors estimate wastage-related losses and discuss opportunities for more circular and sustainable practices in the Italian potato industry.Design/methodology/approachMFA is applied to two specific typologies as follows: ready-to-eat (chips) and dried potato products produced in Italy. The analysis refers to the year 2017 as the complete dataset useful for this study includes measurements until this year. A bottom-up and top-down mixed approach is applied, and functional unit refers to 1 t of potatoes consumed as final product.FindingsMFA is applied to quantify and qualify material balance associated with 1 t of potatoes consumed as final product. In Italy, in 2017, more than 22,000 t of fresh tubers were lost, including 3,500–4,800 t of starch, equivalent to 52,800–72,600 GJs. Moreover, fewer than 23,000 t of skins and scraps were produced within industrial plants, not available for food but suitable for animal feed (dry skins are an excellent carbohydrates source in cattle and poultry feed), starch industry and bioenergy production (biogas and/or bioethanol).Originality/valueThis research is one of the few studies proposing MFA methodology as a tool to measure food waste. This analysis shows its utility in terms of food waste quality/quantity evaluation, supporting both company management and policymakers.

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Guo, Dongming, et Lizhen Huang. « The State of the Art of Material Flow Analysis Research Based on Construction and Demolition Waste Recycling and Disposal ». Buildings 9, n^o 10 (21 septembre 2019) : 207. http://dx.doi.org/10.3390/buildings9100207.

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Construction and demolition waste (C&D waste) are widely recognized as the main form municipal solid waste, and its recycling and reuse are an important issue in sustainable city development. Material flow analysis (MFA) can quantify materials flows and stocks, and is a useful tool for the analysis of construction and demolition waste management. In recent years, material flow analysis has been continually researched in construction and demolition waste processing considering both single waste material and mixed wastes, and at regional, national, and global scales. Moreover, material flow analysis has had some new research extensions and new combined methods that provide dynamic, robust, and multifaceted assessments of construction and demolition waste. In this paper, we summarize and discuss the state of the art of material flow analysis research in the context of construction and demolition waste recycling and disposal. Furthermore, we also identify the current research gaps and future research directions that are expected to promote the development of MFA for construction and demolition waste processing in the field of sustainable city development.

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Day, Arthur L., Christopher G. Gaposchkin, Chun Jiang Yu, Dennis J. Rivet et Ralph G. Dacey. « Spontaneous fusiform middle cerebral artery aneurysms : characteristics and a proposed mechanism of formation ». Journal of Neurosurgery 99, n^o 2 (août 2003) : 228–40. http://dx.doi.org/10.3171/jns.2003.99.2.0228.

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Object. The goal of this study was to identify the origins of spontaneous fusiform middle cerebral artery (MCA) aneurysms. Methods. One hundred two cases of spontaneous fusiform MCA aneurysms were reviewed, including 40 from the authors' institutions and 62 identified from the literature. The mean age at symptom onset was 38 years, and the male/female ratio was 1.4:1. At presentation, the MCA lumen was stenosed or occluded in 12 patients, focally dilated in 57, and appeared “serpentine” in 33. Most lesions originated from the M1 or M2 segments, and most (80%) presented with nonhemorrhagic symptoms or were discovered incidentally. The presenting clinical features correlated with morphological findings in the aneurysms, which could be observed to progress from a small focal dilation or vessel narrowing to a serpentine channel. Hemorrhage was the most common presentation in small lesions; the incidence of bleeding progressively diminished with larger lesions. Patients with stenoses or occluded vessels most often presented with ischemic symptoms, and occasionally with hemorrhage. Giant focal dilations or serpentine aneurysms were rarely associated with acute bleeding; clinical presentation was most often prompted by mass effect or thromboembolic stroke. Conclusions. Analysis of results after various treatments indicates that for symptomatic lesions, therapies that reverse intraaneurysmal blood flow and augment distal cerebral perfusion are associated with better outcomes than other strategies, including conservative management. Based on the spectrum of clinical, pathological, neuroimaging, and intraoperative findings, dissection is proposed as the underlying cause of these lesions.

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Hadžić, Neven, Marko Tomić, Nikola Vladimir et Ivo Senjanović. « Some Aspects of Mega-Floating Airport Design and Production ». Journal of Maritime & ; Transportation Science Special edition, n^o 1 (avril 2016) : 81–99. http://dx.doi.org/10.18048/2016-00.81.

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Mega-Floating Airports (MFA) are unique and complex offshore transport system components that emerged as a consequence of tremendous land price increase in the vicinity of very large coastal cities. An overview of MFAs design and production aspects is presented within this paper including design concept, model tests and full scale measurement, air transport analysis, infrastructure, main particulars and structure, wave breaker, hydroelastic analysis due to wave load and airplane moving mass, mooring analysis, production technology and environmental aspects. MFA dynamic response due to airplane load is emphasized as the most challenging problem. Theoretical outline as well as a realistic illustrative numerical example are presented.

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Ludbrook, Guy L., Elizabeth Visco et Arthur M. Lam. « Propofol ». Anesthesiology 97, n^o 6 (1 décembre 2002) : 1363–70. http://dx.doi.org/10.1097/00000542-200212000-00006.

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Background The potential benefit of propofol dose regimens that use physiologic pharmacokinetic modeling to target the brain has been demonstrated in animals, but no data are available on the rate of propofol distribution to the brain in humans. This study measured the brain uptake of propofol in humans and the simultaneous effects on electroencephalography, cerebral blood flow velocity (V(mca)), and cerebral oxygen extraction. Methods Seven subjects had arterial and jugular bulb catheters placed before induction. Electroencephalography and V(mca) were recorded during induction with propofol while blood samples were taken from both catheters for later propofol analysis. Brain uptake of propofol was calculated using mass balance principles, with effect compartment modeling used to quantitate the rate of uptake. Results Bispectral index (electroencephalogram) values decreased to a minimum value of approximately 4 at around 7 min from the onset of propofol administration and then slowly recovered. This was accompanied by decreases in V(mca), reaching a minimum value of approximately 40% of baseline. Cerebral oxygen extraction did not change, suggesting parallel changes in cerebral metabolism. There was slow equilibrium of propofol between the blood and the brain (t(1/2keo) of 6.5 min), with a close relation between brain concentrations and bispectral index, although with considerable interpatient variability. The majority of the decreases in V(mca), and presumably cerebral metabolism, corresponded with bispectral index values reaching 40-50 and the onset of burst suppression. Conclusion Description of brain distribution of propofol will allow development of physiologic pharmacokinetic models for propofol and evaluation of dose regimens that target the brain.

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Karcagi-Kováts, Andrea. « The use of MFA indicators in the characterization of the settlement sustainability ». Acta Agraria Debreceniensis, n^o 34 (2 septembre 2009) : 107–16. http://dx.doi.org/10.34101/actaagrar/34/2827.

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One of the key sustainability challenges for the coming decades will be to improve the management of natural resources in order to reduce current levels of anthropogenic environmental pressure and respect the biological and physical limits and the carrying capacity of the planet. The first step towards meeting this challenge is an enhancement of the understanding of the material basis of our society. In the past 15 years, scientists in several research institutes have created a fast growing field of research, a new family of different methods, named material flow analysis (MFA). These instruments have an increasing policy relevance: international organizations (UN, EU, OECD) have encouraged member states to establish MFA accounting in their statistical programmes and urged governments and economic actors to use these tools. In this paper I present selected examples to reveal how the MFA approach and derived material flow indicators can be used for the evaluation of sustainability policies at municipality level.

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Kopparapu, Venkata Nanda Kumar, Poornima Kasula, Ajay Kumar Reddy Ankinapalli et M. Venkateswarlu. « RP-HPLC Method Development and Validation For Simultaneous Estimation of Paracetamol and Mefenamic Acid in Pharmaceutical Suspension ». INTERNATIONAL JOURNAL OF PHARMACEUTICAL QUALITY ASSURANCE 10, n^o 04 (21 décembre 2019) : 583–87. http://dx.doi.org/10.25258/ijpqa.10.4.4.

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Paracetamol (PCT) and Mefenamic acid (MFA), in combination, is recommended widely for the treatment of antipyretic and anti-inflammatory conditions. The present works carry a new simple, rapid, precise, accurate, and sensitized method of high-performance liquid chromatography with UV detection for simultaneous quantification of PCT and MFA. The samples are eluted in isocratic mode using a Phenomenex ODS 3V C18 (4.6mm × 250 mm i.d, with a particle size of 5μm) with the mobile composition of methanol: phosphate buffer pH 7.1 (70:30) delivered at a flow rate of 1ml/min with the detection wavelength of 254 nm. It shows good linearity response in the concentration range of 15-35 μg/mL and 6-14 μg/ml for PCT and MFA with the retention times of 3.0 min and 4.8 min, respectively. The quantities of PCT and MFA in pharmaceutical suspension were found to be 99.01% and 101.02%, respectively. The method was quantitatively evaluated according to ICH guidelines taking into consideration the required parameters, and the results obtained are within acceptable limits. So, the proposed method can be employed in the routine analysis and evaluation of MFA and PCT in both bulk and suspension dosage form.

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Agustina, D., A. D. Wicaksono et C. Meidiana. « The application of MFA for rural industrial symbiosis assessment ». IOP Conference Series : Earth and Environmental Science 916, n^o 1 (1 novembre 2021) : 012024. http://dx.doi.org/10.1088/1755-1315/916/1/012024.

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Abstract One of proposed strategies to solve current environmental challenges includes the industrial symbiosis. However, proper evaluation methods are required to measure the potential benefits of industrial symbiosis, one of those includes the material flow analysis (MFA). MFA develops a unified database and a Step-by-Step process starting from the input, process, and output process to clarify the distribution of waste and the recycling process in the aluminum industry. The aluminum industry is regarded as an energy-intensive and high-pollution industry. The development of industrial symbiosis in the aluminum industry has significantly reduced environmental pressures and facilitated green development and green industry. Home industries that process aluminum slag raw materials require high energy thereby generating high waste during the production process. The applied method includes material flow analysis (MFA). The MFA results indicated that the production elements of the aluminum slag industry consist of 11 elements ranging from raw materials, fuel, clean water, human resources, capital, production processes, production equipment, housekeeping, products produced, waste to waste utilization. Approximately 44% of the industry sold waste to other industries, 42% of the waste was reprocessed, and 14% of the aluminum industry stockpiles production was in the form of waste in open spaces. The industrial symbiosis in the aluminum industry was an open cycle, indicating that the symbiosis produces waste, which had not been fully utilized; but in fact, the waste had potential as a source of raw materials, energy, and materials in other industrial processes.

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Sundqvist, Nicolas, Nina Grankvist, Jeramie Watrous, Jain Mohit, Roland Nilsson et Gunnar Cedersund. « Validation-based model selection for 13C metabolic flux analysis with uncertain measurement errors ». PLOS Computational Biology 18, n^o 4 (11 avril 2022) : e1009999. http://dx.doi.org/10.1371/journal.pcbi.1009999.

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Accurate measurements of metabolic fluxes in living cells are central to metabolism research and metabolic engineering. The gold standard method is model-based metabolic flux analysis (MFA), where fluxes are estimated indirectly from mass isotopomer data with the use of a mathematical model of the metabolic network. A critical step in MFA is model selection: choosing what compartments, metabolites, and reactions to include in the metabolic network model. Model selection is often done informally during the modelling process, based on the same data that is used for model fitting (estimation data). This can lead to either overly complex models (overfitting) or too simple ones (underfitting), in both cases resulting in poor flux estimates. Here, we propose a method for model selection based on independent validation data. We demonstrate in simulation studies that this method consistently chooses the correct model in a way that is independent on errors in measurement uncertainty. This independence is beneficial, since estimating the true magnitude of these errors can be difficult. In contrast, commonly used model selection methods based on the χ2-test choose different model structures depending on the believed measurement uncertainty; this can lead to errors in flux estimates, especially when the magnitude of the error is substantially off. We present a new approach for quantification of prediction uncertainty of mass isotopomer distributions in other labelling experiments, to check for problems with too much or too little novelty in the validation data. Finally, in an isotope tracing study on human mammary epithelial cells, the validation-based model selection method identified pyruvate carboxylase as a key model component. Our results argue that validation-based model selection should be an integral part of MFA model development.

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Ali, Nora Aini, Latifah Ghani et Noor Zalina Mahmood. « Modelling of Nitrogen and Phosphorus Flow in Wastewater Management : Case Study for Terengganu, Malaysia ». Applied Mechanics and Materials 295-298 (février 2013) : 1005–12. http://dx.doi.org/10.4028/www.scientific.net/amm.295-298.1005.

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The Material Flow Analysis (MFA) method is often discussed in terms of water resources management. This paper attempts to measure and analyze the flow of nitrogen and phosphorus from wastewater sources to assess the trends and patterns of strain in environmental metabolism.Comparison between nitrogen and phosphorus accumulates in wastewater shows that, P discharged values to sewer system are lower as compared to N. Kemaman dan Kuala Terengganu are the dominant region that generating high volume of P and N-wastewater discharge.The study also delved mostly into recycling level of effluent and sludge, with only 3 to 5% of both products were reuse for agriculture and economic purpose. In conclusion, MFA techniques have been proposed to help the decision-makers in waste and nutrient management planning especially on implementing policies related to water and wastewater sectors.

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dos Muchangos, Leticia Sarmento, Akihiro Tokai et Atsuko Hanashima. « Application of material flow analysis to municipal solid waste in Maputo City, Mozambique ». Waste Management & ; Research : The Journal for a Sustainable Circular Economy 35, n^o 3 (5 décembre 2016) : 253–66. http://dx.doi.org/10.1177/0734242x16678067.

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Understanding waste flows within an urban area is important for identifying the main problems and improvement opportunities for efficient waste management. Assessment tools such as material flow analysis (MFA), an extensively applied method in waste management studies, provide a structured and objective evaluating process to characterize the waste management system best, to identify its shortcomings and to propose suitable strategies. This paper presents the application of MFA to municipal solid waste management (MSWM) in Maputo City, the capital of Mozambique. The results included the identification and quantification of the main input and output flows of the MSWM system in 2007 and 2014, from the generation, material recovery and collection, to final disposal and the unaccounted flow of municipal solid waste (MSW). We estimated that the waste generation increased from 397×103 tonnes in 2007 to 437×103 tonnes in 2014, whereas the total material recovery was insignificant in both years – 3×103 and 7×103 tonnes, respectively. As for collection and final disposal, the official collection of waste to the local dumpsite in the inner city increased about threefold, from 76×103 to 253×106 tonnes. For waste unaccounted for, the estimates indicated a reduction during the study period from 300×103 to 158×103 tonnes, due to the increase of collection services. The emphasized aspects include the need for practical waste reduction strategies, the opportunity to explore the potential for material recovery, careful consideration regarding the growing trend of illegal dumping and the urgency in phasing-out from the harmful practice of open dumping.

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Vujic, Goran, Nebojsa Jovicic, Milun Babic, Nemanja Stanisavljevic, Bojan Batinic et Aleksandar Pavlovic. « Assessment of plastic flows and stocks in Serbia using material flow analysis ». Thermal Science 14, suppl. (2010) : 89–95. http://dx.doi.org/10.2298/tsci100621031v.

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Material flow analysis (MFA) was used to assess the amounts of plastic materials flows and stocks that are annually produced, consumed, imported, exported, collected, recycled, and disposed in the landfills in Serbia. The analysis revealed that approximatelly 269,000 tons of plastic materials are directly disposed in uncontrolled landfills in Serbia without any preatretment, and that siginificant amounts of these materials have already accumulated in the landfills. The substantial amounts of landfilled plastics represent not only a loss of valuable recourses, but also pose a seriuos treath to the environment and human health, and if the trend of direct plastic landfilling is continued, Serbia will face with grave consecequnces.

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Binder, Claudia R. « From material flow analysis to material flow management Part I : social sciences modeling approaches coupled to MFA ». Journal of Cleaner Production 15, n^o 17 (novembre 2007) : 1596–604. http://dx.doi.org/10.1016/j.jclepro.2006.08.006.

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Yan, Bin, Rong Shi, Yi-yu Lu, Dong-dong Fang, Mei-na Ye et Qian-mei Zhou. « Shenqi Fuzheng injection reverses M2 macrophage-mediated cisplatin resistance through the PI3K pathway in breast cancer ». PLOS ONE 18, n^o 1 (24 janvier 2023) : e0279752. http://dx.doi.org/10.1371/journal.pone.0279752.

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Background Shenqi Fuzheng injection (SQFZ) combined with chemotherapy can sensitize tumour cells. However, the mechanisms underlying SQFZ’s effects remain unknown. In human breast cancer cell lines and M2 macrophages, we showed that SQFZ was a significantly potent agent of sensitization. Methods The human breast cancer cell line, MDA-MB-231/DDP, and the human acute leukaemia mononuclear cell line, THP-1, were used. MDA-MB-231/DDP breast cancer xenografts were established to monitor tumour growth. Resistance-associated proteins were examined by western blotting. Levels of cytokines and chemokines were detected by ELISA. Cell viability was measured using the MTT assay. Apoptosis was detected by flow cytometric analysis. Results SQFZ significantly enhanced the capability of cisplatin to reduce tumour mass. SQFZ and cisplatin decreased the expression of CD206 by 1.89-fold and increased that of CD86 by 1.76-fold as compared to cisplatin alone. The levels of PGE2, IL-6, and CCL1 decreased significantly, and the activation of p-PI3K and the expressions of P-gp and ABCG2 were also inhibited by SQFZ in combination with cisplatin treatment in vivo. The survival following cisplatin administration of 60 μM and 120 μM reduced significantly in the presence of SQFZ in MDA-MB-231/DDP and M2 co-cultured cells. IGF-1, a PI3K activator, combined with SQFZ weakened the effects of SQFZ-induced apoptosis from 28.7% to 10.5%. The effects of IGF-1 on increasing the expressions of P-gp, ABCG2, and Bcl-2, and decreasing that of Bax were reversed by SQFZ. Conclusion Our findings provide evidence that SQFZ is a potential therapeutic drug for cancer therapy.

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Zarogiannis, Theodoros, Athanasios I. Papadopoulos et Panos Seferlis. « Off-Design Operation of Conventional and Phase-Change CO2 Capture Solvents and Mixtures : A Systematic Assessment Approach ». Applied Sciences 10, n^o 15 (31 juillet 2020) : 5316. http://dx.doi.org/10.3390/app10155316.

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Solvent-based CO2 capture technologies hold promise for future implementation but conventional solvents incur significant energy penalties and capture costs. Phase-change solvents enable a significant reduction in the regeneration energy but their performance has only been investigated under steady-state operation. In the current work, we employed a systematic approach for the evaluation of conventional solvents and mixtures, as well as phase-change solvents under the influence of disturbances. Sensitivity analysis was used to identify the impact that operating parameter variations and different solvents exert on multiple CO2 capture performance indicators within a wide operating range. The resulting capture process performance was then assessed for each solvent within a multi-criteria approach, which simultaneously accounted for off-design conditions and nominal operation. The considered performance criteria included the regeneration energy, solvent mass flow rate, cost and cyclic capacity, net energy penalty from integration with an upstream power plant, and lost revenue from parasitic losses. The 10 investigated solvents included the phase-change solvents methyl-cyclohexylamine (MCA) and 2-(diethylamino)ethanol/3-(methylamino)propylamine (DEEA/MAPA). We found that the conventional mixture diethanolamine/methyldiethanolamine (DEA/MDEA) and the phase-change solvent DEEA/MAPA exhibited both resilience to disturbances and desirable nominal operation for multiple performance indicators simultaneously.

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