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Anticancer drugs alter active nitrogen-cycling communities with effects on the nitrogen removal efficiency of a continuous-flow aerobic granular sludge system

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Chemosphere 2025年 376卷 144279页

作者： Castellano-Hinojosa, Antonio Gallardo-Altamirano, Manuel J. Santo Svierzoski, Nicoly Dal Pozo, Clementina González-López, Jesús González-Martínez, Alejandro Environmental Microbiology Group Institute of Water Research University of Granada Granada18003 Spain Department of Microbiology University of Granada Granada18071 Spain Civil Engineering Program COPPE Federal University of Rio de Janeiro Rio de Janeiro Brazil

There is increasing awareness of the presence of anticancer drugs (ACDs) in wastewater. Nonetheless, how ACDs affect the performance of wastewater treatment systems and their microbial populations remains largely unclear. This study investigated the effects of three common ACDs (cyclophosphamide, tamoxifen, and methotrexate) at varying concentrations on physicochemical parameters and drug removal efficiency in an aerobic granular sludge (AGS) system operated in a continuous-flow reactor. Additionally, it examined the abundance of active microbial communities, including nitrifiers (amoA gene from ammonia-oxidizing bacteria and archaea) and denitrifiers (napA, narG, nirK, nirS, nosZ genes), as well as the biodiversity of active prokaryotic communities. The concentration level of ACDs determines variations in biomass density, granule integrity, and removal efficiencies of organic matter (OM) and total nitrogen. Both medium and high ACD concentrations negatively impact these physicochemical parameters. The findings revealed that AGS functioning within a continuous system could help remove ACDs, but removal efficiencies depended on the specific drug and concentration applied. At medium and high ACD concentrations a marked reduction in the abundance of active bacterial and archaeal communities, including nitrifiers and denitrifiers, was observed, alongside a decline in microbial diversity and a transformation in community composition. Specific bacterial genera, which are crucial for OM degradation, nitrification and denitrification were identified as particularly sensitive to anticancer drugs. Our findings highlight the need for monitoring and managing anticancer drugs in wastewater systems, as they can substantially alter treatment performance, nitrogen-cycling communities, and bacterial community composition. © 2025 Elsevier Ltd

关键词： Cytotoxic Denitrification Granular Microbial abundance Nitrification Wastewater

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Numerical model for analysis of offshore structures subjected to pool fires

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Marine Systems and Ocean Technology 2016年第1-2期11卷 19-29页

作者： Manco, Miguel R. Landesmann, Alexandre Vaz, Murilo A. Cyrino, Julio C. R. Ocean Engineering Program COPPE/Federal University of Rio de Janeiro Rio de Janeiro Brazil Civil Engineering Program COPPE/Federal University of Rio de Janeiro Rio de Janeiro Brazil

This paper introduces a numerical model to assess the thermomechanical behavior of offshore structures subjected to pool fires. The aim of this model is to improve the representation of fires in comparison with other existing models (e.g., nominal fire curves or zone modeling). The method proposed combines two-zone model—2ZM and a modified solid flame model—MSFM for calculating the convection and radiation portions of the heat transfer process between the fire and the structure. Thermal and mechanical analyses are performed sequentially using the commercial Finite Element Analysis software ABAQUS®. To assess the structure’s behavior, the transient temperature field resulting from the preceding thermal analysis is used together with pre-existing operating loads for the mechanical analysis. A pool fire in a tank barge is presented as a case study. Comparison of temperature and strain fields obtained with the method proposed to the results of other methods for assessment of the casualty indicates that the new model allows more realistic estimation of the temperature fields produced by the fire with relatively low computational costs. © 2016, Sociedade Brasileira de Engenharia Naval.

关键词： Fires

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Optimization of open cold-formed steel sections based on shape grammar

Optimization of open cold-formed steel sections based on sha...

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Structural Stability Research Council Annual Stability Conference 2014, SSRC 2014

作者： Franco, J.M.S. Batista, E.M. Landesmann, A. Civil Engineering Program COPPE Federal University of Rio de Janeiro Brazil

ISBN: (纸本)9781632667106

The main goal of the present research is to find innovative and appropriate CFS shapes, improving its structural behavior at the same time that are manufacturable and, if possible, cost saving. Open cold-formed steel sections (CFS) optimization is obtained by integration of four investigation fields: (i) modeling the search domain, (ii) designing the fitness functions, (iii) applying Artificial Intelligence and (iv) computational implementation and visualization integrates the three other investigation fields. The paper focuses innovative application of Shape Grammar formalism, addressed to easy modeling of feasible CFS sections. The original developed algorithm is identified as CFS-Language - composed by a set of sentences translating each step of manufacturing by cold-forming - which was combined with Genetic Algorithm in order to select adequate shape, in accordance with previously selected objectives (Pareto's Front). The results of the analysis for three fitness functions are presented: (i) axial compression and (ii) flexural strength with the help of the Direct Strength Method and (iii) manufacturing costs. CFS-language was firstly developed in a CAD platform, further translated to MATLAB code and finally integrated with GA procedure inside the open-source code CUFSM (v.4.0.5) for buckling analysis based on constrained finite strip method. Based on the above described methodology, CFS shapes were generated by combining fitness functions and geometric modeling algorithms through Genetic Algorithm. The paper presents in detail the developed CFS-language, shows how the computational algorithms were integrated and finally presents the results of illustrative examples.

关键词： Genetic algorithms

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Composite floor system with cold-formed trussed beams and prefabricated concrete slab

Composite floor system with cold-formed trussed beams and pr...

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2019 International Colloquium on Stability and Ductility of Steel Structures, SDSS 2019

作者： De Leal, Luiz Alberto A.S. De Batista, Eduardo M. Federal University of Rio de Janeiro COPPE Civil Engineering Program Brazil

Composite steel and concrete floor systems are usual solution for building construction, conducting to reduce material consumption, improve structural strength and flexural stiffness. Steel frame light construction systems, based on combination of thin-walled cold-formed steel members (CFS) and panels (e.g wood, cementitious, gypsum plaster), may also benefit of composite behavior for the case of concrete slabs. In this context, full-scale experimental tests were conducted to evaluate the structural behavior of floor system conceived with 0.95-mm thick CFS trussed beams and pre-fabricated concrete slabs. Innovative solution for shear connectors was designed and tested, in order to ensure full interaction between the CFS trussed beam and concrete slab. Thin-Walled Channel connector (TWC) is based on lipped channel CFS attached to the top chord of the truss by self-drilling screws. Experimental results indicate efficient behavior of TWC shear connectors with improved bending capacity of the floor system. © SDSS 2019 - International Colloquium on Stability and Ductility of Steel Structures.

关键词： Floors

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Artificial Intelligence (AI) applied to waste management: A contingency measure to fill out the lack of information resulting from restrictions on field sampling

Waste Management Bulletin

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Waste Management Bulletin 2023年第3期1卷 11-17页

作者： Pinhal Luqueci Thomaz, Igor Fernando Mahler, Claudio Pereira Calôba, Luiz Civil Engineering Program COPPE Federal University of Rio de Janeiro Rio de Janeiro Brazil Electrical Engineering Program COPPE Federal University of Rio de Janeiro Rio de Janeiro Brazil

Waste characterization is essential in planning to reduce waste, create recycling programs and properly use public funds. Traditionally, waste characterization is successfully performed by on-site sampling. This monitoring requires specialized professionals following safety protocols to decrease the health risks associated with the waste handling. However, on-site sampling is susceptible to restrictions in mandatory quarantine situations. Here we show the possibility of using Artificial Intelligence applied to waste management. We identified an Artificial Neural Network (ANN) model fed by combination of population, Gross Domestic Product, Potable Water Supply and Sanitation System data that could be used to fill gaps related to the pandemic period. The modified model predictions were successful due to the adaptive capacity of the ANN-based models. Our results demonstrate that ANN can be used in contingency plans to predict the gravimetric composition and specific weight of Municipal Solid Waste, based on strategically chosen socioeconomic information. We anticipate that our model will be a starting point for more sophisticated computational models. It will allow not only the filling of gaps but also the use for auditing, because it allows analyzing the consistency of gravimetric composition and specific weight data provided by third parties. © 2023 The Authors

关键词： Artificial Neural Network Characterization Municipal Solid Waste Pandemic Socioeconomic factors

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Cold-formed steel lipped channel beams under fire conditions: Distortional response, failure and DSM design

Cold-formed steel lipped channel beams under fire conditions...

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Structural Stability Research Council Annual Stability Conference 2014, SSRC 2014

作者： Landesmann, A. Camotim, D. Civil Engineering Program COPPE Federal University of Rio de Janeiro Brazil Civil Engineering Department ICIST University of Lisbon Portugal

ISBN: (纸本)9781632667106

The aim of this paper is to report an ongoing shell finite element investigation on the distortional post-buckling behavior, ultimate strength and design of cold-formed steel single-span lipped channel beams subjected to elevated temperatures caused by fire conditions. The beam ultimate strengths are computed by means of a steady-state loading strategy that consists of applying an increasing major-axis uniform bending moment to a beam under a uniform (elevated) temperature distribution, in order to obtain the corresponding failure moments). The steel constitutive law at elevated temperatures is simulated by means of the stress-strain-temperature models prescribed in EC3-1.2 for cold-formed steel. The materially and geometrically non-linear response of the cold-formed lipped channel beams is determined by means of ANSYS non-linear shell finite element analyses that incorporate critical-mode initial geometrical imperfections. Finally, since there are no specific rules to predict the bending strength of cold-formed steel beams failing distortionally when subjected to elevated temperatures, the above failure moments and temperature values will be used to establish guidelines for the design of cold-formed steel lipped channel beams under fire conditions. The approach followed is based on the increasingly popular Direct Strength Method, already employed by other researchers (e.g., Ranawaka and Mahendran 2009b) - the currently available design/strength equations/curves, developed for ambient temperature, are modified to account for the appropriate Young's modulus and yield stress reductions due to the temperature increase.

关键词： Yield stress

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The effective section method for the design of thin-walled cold-formed steel members

The effective section method for the design of thin-walled c...

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2010 Annual Stability Conference, SSRC 2010

作者： Batista, Eduardo De Miranda Civil Engineering Program COPPE Federal University of Rio de Janeiro Rio de Janeiro Brazil

ISBN: (纸本)1879749777

Considering the well known advantages of the Direct Strength Method if compared with the Effective Width Method for the design of thin-walled cold-formed steel members, but also the difficulties arising from the necessity to perform computational analysis to find the actual critical buckling loading which support the DSM design formulation, an alternative design procedure was validated in order to make it simpler and direct the application of the DS principles for the case of local-global buckling interaction. In addition, the proposed formulation make it easier integrating the direct strength principles side-by-side with the EWM, avoiding manipulation of computational programs, at least for the most usual cold-formed shapes. The Effective Section Method was included in the 2009 edition of the revision of the Brazilian code NBR 14762 after extensive calibration against experimental results of columns and beams. The ESM formulation for resistance design keeps the original idealization of "reduced" or "effective" cross-section geometry (A ef for columns and Weffor beams) but, on the contrary of the EWM, these reduced geometrical properties are based on the actual local plate buckling behavior of the member. The option to adopt direct access to local buckling loading by equations and tables is also available in the Brazilian code. This solution improved the attractiveness of the ESM and allowed easy way to apply direct strength principles, as well as assured more accurate design rules if compared with the classical EWM prescriptions.

关键词： Buckling

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Local/distortional/global interaction in lipped channel columns: Behaviour and strength

Local/distortional/global interaction in lipped channel colu...

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6th International Conference on Advances in Steel Structures and Progress in Structural Stability and Dynamics, ICASS 2009

作者： Dinis, Pedro B. Camotim, Dinar Batista, Eduardo M. Santos, Eliane Department of Civil Engineering ICIST/IST Technical University of Lisbon Portugal Civil Engineering Program COPPE Federal University of Rio de Janeiro Brazil

ISBN: (纸本)9789889914059

This paper reports the available results of an ongoing numerical and experimental investigation on the post-buckling behaviour and strength of fixed-ended cold-formed steel lipped channel columns affected by local/distortional/global (flexural-torsional) mode interaction. Initially, ABAQUS shell finite element results concerning columns exhibiting identical local, distortional and global buckling loads (their geometries are identified through preliminary buckling analyses) are presented and discussed otherwise identical columns containing critical-mode initial geometrical imperfections with different configurations are analysed. These numerical results include (i) elastic and elastic-plastic post-buckling equilibrium paths, (ii) curves and figures providing the evolution, along a given path, of the column deformed configuration and (iii) the characterisation of the column collapse mechanism. Then, the paper addresses the experimental investigation currently under way at coppe (federal University of Rio de Janeiro) and to be fully reported in the near future experimental and numerical results concerning one test are presented and discussed.

关键词： Finite element method

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RHS beam-to-column connection: Experimental analysis of innovative bolted typology 15

RHS beam-to-column connection: Experimental analysis of inno...

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Proceedings of the 15th International Symposium on Tubular Structures, ISTS 2015

作者： Dos Santos, G.B. De Batista, E.M. De Araújo, A. Civil Engineering Program COPPE Federal University of Rio de Janeiro Brazil Vallourec Research Center Brasil Brazil

ISBN: (纸本)9781138028371

The main purpose of the present research is to investigate the behavior of innovative beamto- column bolted connection of steel rectangular hollow sections – RHS. The typology of the connection was conceived to combine simplicity in fabrication and erection with structural effectiveness. The connection components are two cleat plates butt-welded or inserted through the RHS column, internally connected to the webs of the RHS beam with top and bottom horizontal lines of bolts. In addition, the tested connections were divided in two concepts concerning the bolts tightening: (i) regular manual tightening and (ii) pre stressed bolts by controlled tightening. The former allows usual non-friction connection and the later permitted to investigate friction-type. The experimental results permitted to identify the connections bending moment-rotation behavior and comparison with usual concepts of rigid, semi-rigid or flexible classification, in order to support structural design procedures. © 2015 Taylor & Francis Group, London.

关键词： Friction

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Towards a more rational DSM design approach for angle columns

Towards a more rational DSM design approach for angle column...

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Structural Stability Research Council Annual Stability Conference 2013, SSRC 2013

作者： Dinis, P.B. Camotim, D. Landesmann, A. Civil Engineering Department Instituto Superior Técnico Technical University Lisbon Portugal Civil Engineering Program COPPE Federal University Rio de Janeiro Brazil

ISBN: (纸本)9781627483384

This paper deals with the development of novel procedures for the design of fixed-ended and pin-ended equal-leg angle columns with short-to-intermediate lengths, i.e., those buckling in flexural-torsional modes. Initially, numerical results concerning the buckling and post-buckling behavior of the above angle columns are presented, (i) highlighting the main differences between the fixed-ended and pin-ended column responses, and (ii) evidencing the need for specific design procedures. Then, the paper gathers a large column ultimate strength data bank that includes (i) experimental values, collected from the available literature, and (ii) numerical values, obtained from Abaqus shell finite element analyses. The set of experimental results collected comprises 41 fixed-ended and 35 pin-ended columns, and the numerical results obtained concern 92 fixed-ended and 64 pin-ended columns - various cross-section dimensions, lengths and yield stresses are considered. Next, after reviewing the available methods to estimate the ultimate strength of angle columns, the paper develops new design approaches for fixed-ended and pin-ended columns, based on the Direct Strength Method (DSM) - the mechanical reasoning behind the procedures proposed, which include the use of genuine flexural-torsional strength curves, is also provided. Finally, the paper closes with the assessment of the ultimate strength predictions yielded by the proposed DSM design procedures, through their comparison with the assembled experimental and numerical failure loads - it is shown that both the quality and reliability of these predictions are very good and slightly higher than those exhibited by all the available design methods for angle columns. Copyright © (2013) by the Structural Stability Research Council (SSRC).

关键词： Stability

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