Would RC wide-beam buildings in Spain have survived Lorca earthquake (11-05-2011)?

Lorca earthquake (11-05-2011) is most destructive event recorded in Spain, causing nine fatalities and other severe consequences. Its important intensity was rather unexpected, and serious concern arose regarding risk of building stock in Spain. This paper analyzes performance, under Lorca earthquake, of RC buildings with one-way slabs with wide beams. This construction type is chosen for its high vulnerability and for being vastly widespread in Spain. This study is conducted on 3 and 6-story prototype representative buildings. These buildings are designed for three major seismic zones in Spain: low seismicity, moderate seismicity (as Lorca) and medium seismicity (as Granada). Seismic performance under Lorca earthquake is numerically investigated through nonlinear time-history analyses. Results show that buildings designed without any seismic provision (i.e. those in low seismicity zones) do not survive Lorca record, even with cooperation of masonry infill walls. Buildings with seismic design (i.e. those in Lorca and Granada zones) can survive Lorca earthquake only with collaboration of infill walls. To raise reliability of these conclusions, a sensitivity analysis to most influencing parameters is conducted.Postprint (author's final draft

Seismic vulnerability analysis of wide-beam buildings in Spain

A number of short-to-mid height RC buildings with wide beams have been constructed in moderate-seismicity areas of Spain. The seismic behavior in the direction of the wide beams appears to be deficient because of low lateral strength, low ductility of the wide beams, big strut compressive forces inside the column-beam connections, and unreliable contribution of the spandrel zones of the wide beams. In the orthogonal direction, the behavior is worse since only the joists and the façade beams contribute to the lateral resistance. The objective is to assess the seismic capability of these structures; further research will involve proposing retrofit strategies. The research approach consists of selecting a number of representative buildings and evaluating their vulnerability by code-type, push-over and dynamic analyses. The cooperation of the masonry infill walls is accounted for. The main conclusion is that the seismic behavior of these buildings is inadequate in most of the situations

Vulnerability analysis of RC buildings with wide beams located in moderate seismicity regions

A significant number of short-to-mid height RC buildings with wide beams have been constructed in areas of moderate seismicity of Spain, mainly for housing and administrative use. The buildings have a framed structure with one-way slabs; the wide beams constitute the distinctive characteristic, their depth being equal to that of the rest of the slab, thus providing a flat lower surface, convenient for construction and the layout of facilities. Seismic behavior in the direction of the wide beams appears to be deficient because of: (i) low lateral strength, mainly because of the small effective depth of the beams, (ii) inherent low ductility of the wide beams, generated by high amount of reinforcement, (iii) the big strut compressive forces developed inside the column-beam connections due to the low height of the beams, and (iv) the fact that the wide beams are wider than the columns, meaning that the contribution of the outer zones to the resistance of the beam-column joints is unreliable because there is no torsion reinforcement. In the orthogonal direction, the behavior is worse since the only members of the slabs that contribute to the lateral resistance are the joists and the façade beams. Moreover, these buildings were designed with codes that did not include ductility requirements and required only a low lateral resistance; indeed, in many cases, seismic action was not considered at all. Consequently, the seismic capacity of these structures is not reliable. The objective of this research is to assess numerically this capability, whereas further research will aim to propose retrofit strategies. The research approach consists of: (i) selecting a number of 3-story and 6-story buildings that represent the vast majority of the existing ones and (ii) evaluating their vulnerability through three types of analyses, namely: code-type, push-over and nonlinear dynamic analysis. Given the low lateral resistance of the main frames, the cooperation of the masonry infill walls is accounted for; for each representative building, three wall densities are considered. The results of the analyses show that the buildings in question exhibit inadequate seismic behavior in most of the examined situations. In general, the relative performance is less deficient for Target Drift CP (Collapse Prevention) than for IO (Immediate Occupancy). Since these buildings are selected to be representative of the vast majority of buildings with wide beams that were constructed in Spain without accounting for any seismic consideration, our conclusions can be extrapolated to a broader scenario

Using ecosystem services to represent the environment in hydro-economic models

[EN] Demand for water is expected to grow in line with global human population growth, but opportunities to augment supply are limited in many places due to resource limits and expected impacts of climate change. Hydro-economic models are often used to evaluate water resources management options, commonly with a goal of understanding how to maximise water use value and reduce conflicts among competing uses. The environment is now an important factor in decision making, which has resulted in its inclusion in hydro-economic models. We reviewed 95 studies applying hydro-economic models, and documented how the environment is represented in them and the methods they use to value environmental costs and benefits. We also sought out key gaps and inconsistencies in the treatment of the environment in hydro-economic models. We found that representation of environmental values of water is patchy in most applications, and there should be systematic consideration of the scope of environmental values to include and how they should be valued. We argue that the ecosystem services framework offers a systematic approach to identify the full range of environmental costs and benefits. The main challenges to more holistic representation of the environment in hydro-economic models are the current limits to understanding of ecological functions which relate physical, ecological and economic values and critical environmental thresholds; and the treatment of uncertainty. (C) 2016 Elsevier B.V. All rights reserved.The authors acknowledge the backing of Universitat Politecnica de Valencia through its Support Programme for Research and Development. Support by the CSIRO for an internship visit by the lead author is also acknowledged. We also wish to thank the European Commission for financing the Seventh Framework Program project ENHANCE (FP7-ENV-2012, 308438) and the H2020 project IMPREX (H2020-WATER-2014-2015, 641811), and the Spanish Ministry of Economy and Competitiveness for granting the project NUTEGES (VI Plan Nacional de I+D+i 2008-2011, CGL2012-34978).Momblanch Benavent, A.; Connor, JD.; Crossman, ND.; Paredes Arquiola, J.; Andreu Álvarez, J. (2016). Using ecosystem services to represent the environment in hydro-economic models. Journal of Hydrology. 538:293-303. https://doi.org/10.1016/j.jhydrol.2016.04.019S29330353

The active metabolite of leflunomide, A77 1726, inhibits the production of prostaglandin E2, matrix metalloproteinase 1 and interleukin 6 in human fibroblast‐like synoviocytes

Objectives. To investigate the effects of the active metabolite of leflunomide, A77 1726, on fibroblast‐like synoviocytes. In rheumatoid arthritis (RA) synoviocytes participate in tissue destruction by producing metalloproteinases (MMP), prostaglandin E2 (PGE2) and interleukin (IL) 6, which are involved in extracellular matrix degradation, resorption of the mineral phase and osteoclast‐mediated bone resorption. Methods. Human synoviocytes were stimulated with IL‐1α or tumour necrosis factor α (TNF‐α) in the presence of A77 1726. Culture supernatants were analysed for production of interstitial collagenase (MMP‐1), tissue‐inhibitor of metalloproteinases 1 (TIMP‐1), PGE2 and IL‐6. Total RNA was isolated and analysed for steady‐state levels of MMP‐1, cyclooxygenase‐2 (COX‐2) and IL‐6 mRNA. Results. A77 1726 inhibited the production of PGE2 in synoviocytes activated by TNF‐α and IL‐1α with median inhibitory concentrations (IC50) of 7 and 3 µm respectively. In contrast, MMP‐1 and IL‐6 production was inhibited at high A77 1726 concentrations (> 10 µm), whereas TIMP‐1 was not affected. The inhibition of MMP‐1 and IL‐6 production was due to the known inhibitory effect of A77 1726 on pyrimidine synthesis, as it was reversed by the addition of uridine. This did not apply to PGE2 production, which was inhibited via direct action of A77 1726 on COX‐2, as shown by the increasing amount of substrate (arachidonic acid) in the culture medium. Conclusion. This study shows that some of the beneficial effect of leflunomide in RA patients may be due to the inhibition of PGE2, IL‐6 and MMP‐1 production in synoviocytes. This effect, coupled with its multiple inhibitory effects on T lymphocyte functions, might account for the significant reduction in the rate of disease progression in RA patients treated with leflunomid

Predictive model to identify multiple failure to biological therapy in patients with rheumatoid arthritis

Despite advances in the treatment of rheumatoid arthritis (RA) and the wide range of therapies available, there is a percentage of patients whose treatment presents a challenge for clinicians due to lack of response to multiple biologic and target-specific disease-modifying antirheumatic drugs (b/tsDMARDs).To develop and validate an algorithm to predict multiple failure to biological therapy in patients with RA.Observational retrospective study involving subjects from a cohort of patients with RA receiving b/tsDMARDs.Based on the number of prior failures to b/tsDMARDs, patients were classified as either multi-refractory (MR) or non-refractory (NR). Patient characteristics were considered in the statistical analysis to design the predictive model, selecting those variables with a predictive capability. A decision algorithm known as 'classification and regression tree' (CART) was developed to create a prediction model of multi-drug resistance. Performance of the prediction algorithm was evaluated in an external independent cohort using area under the curve (AUC).A total of 136 patients were included: 51 MR and 85 NR. The CART model was able to predict multiple failures to b/tsDMARDs using disease activity score-28 (DAS-28) values at 6 months after the start time of the initial b/tsDMARD, as well as DAS-28 improvement in the first 6 months and baseline DAS-28. The CART model showed a capability to correctly classify 94.1% NR and 87.5% MR patients with a sensitivity = 0.88, a specificity = 0.94, and an AUC = 0.89 (95% CI: 0.74-1.00). In the external validation cohort, 35 MR and 47 NR patients were included. The AUC value for the CART model in this cohort was 0.82 (95% CI: 0.73-0.9).Our model correctly classified NR and MR patients based on simple measurements available in routine clinical practice, which provides the possibility to characterize and individualize patient treatments during early stages.© The Author(s), 2022

Global mapping of randomised trials related articles published in high-impact-factor medical journals: a cross-sectional analysis

BACKGROUND: Randomised controlled trials (RCTs) provide the most reliable information to inform clinical practice and patient care. We aimed to map global clinical research publication activity through RCT-related articles in high-impact-factor medical journals over the past five decades. METHODS: We conducted a cross-sectional analysis of articles published in the highest ranked medical journals with an impact factor > 10 (according to Journal Citation Reports published in 2017). We searched PubMed/MEDLINE (from inception to December 31, 2017) for all RCT-related articles (e.g. primary RCTs, secondary analyses and methodology papers) published in high-impact-factor medical journals. For each included article, raw metadata were abstracted from the Web of Science. A process of standardization was conducted to unify the different terms and grammatical variants and to remove typographical, transcription and/or indexing errors. Descriptive analyses were conducted (including the number of articles, citations, most prolific authors, countries, journals, funding sources and keywords). Network analyses of collaborations between countries and co-words are presented. RESULTS: We included 39,305 articles (for the period 1965-2017) published in forty journals. The Lancet (n = 3593; 9.1%), the Journal of Clinical Oncology (n = 3343; 8.5%) and The New England Journal of Medicine (n = 3275 articles; 8.3%) published the largest number of RCTs. A total of 154 countries were involved in the production of articles. The global productivity ranking was led by the United States (n = 18,393 articles), followed by the United Kingdom (n = 8028 articles), Canada (n = 4548 articles) and Germany (n = 4415 articles). Seventeen authors who had published 100 or more articles were identified; the most prolific authors were affiliated with Duke University (United States), Harvard University (United States) and McMaster University (Canada). The main funding institutions were the National Institutes of Health (United States), Hoffmann-La Roche (Switzerland), Pfizer (United States), Merck Sharp & Dohme (United States) and Novartis (Switzerland). The 100 most cited RCTs were published in nine journals, led by The New England Journal of Medicine (n = 78 articles), The Lancet (n = 9 articles) and JAMA (n = 7 articles). These landmark contributions focuse

Ductility of wide-beam RC frames as lateral resisting system

[EN] Some Mediterranean seismic codes consider wide-beam reinforced concrete moment resisting frames (WBF) as horizontal load carrying systems that cannot guarantee high ductility performances. Conversely, Eurocode 8 allows High Ductility Class (DCH) design for such structural systems. Code prescriptions related to WBF are systematically investigated. In particular, lesson learnt for previous earthquakes, historical reasons, and experimental and numerical studies underpinning specific prescriptions on wide beams in worldwide seismic codes are discussed. Local and global ductility of WBF are then analytically investigated through (1) a parametric study on chord rotations of wide beams with respect to that of deep beams, and (2) a spectral-based comparison of WBF with conventional reinforced concrete moment resisting frames (i.e. with deep beams). Results show that the set of prescriptions given by modern seismic codes provides sufficient ductility to WBF designed in DCH. In fact, global capacity of WBF relies more on the lateral stiffness of the frames and on the overstrength of columns rather than on the local ductility of wide beams, which is systematically lower with respect to that of deep beams.Gómez-Martínez, F.; Alonso Durá, A.; De Luca, F.; Verderame, GM. (2016). Ductility of wide-beam RC frames as lateral resisting system. Bulletin of Earthquake Engineering. 14(6):1545-1569. doi:10.1007/s10518-016-9891-xS15451569146ACI (1989) Building code requirements for reinforced concrete (ACI 318-89). ACI Committee 318, American Concrete Institute, Farmington Hills, Michigan, USAACI (2008) Building code requirements for structural concrete (ACI 318-08) and commentary (318-08). ACI Committee 318, American Concrete Institute, Farmington Hills, Michigan, USAACI-ASCE (1991) Recommendations for design of beam-column connections in monolithic reinforced concrete structures (ACI 352R-91). Joint ACI-ASCE Committee 352, American Concrete Institute, Farmington Hills, Michigan, USAACI-ASCE (2002) Recommendations for design of beam-column connections in monolithic reinforced concrete structures (ACI 352R-02). Joint ACI-ASCE Committee 352, American Concrete Institute, Farmington Hills, Michigan, USAArslan MH, Korkmaz HH (2007) What is to be learned from damage and failure of reinforced concrete structures during recent earthquakes in Turkey? Eng Fail Anal 14(1):1–22ASCE (2007) Seismic Rehabilitation of Existing Buildings, ASCE/SEI 41-06. American Society of Civil Engineers, RestonASCE (2010) Minimum Design Loads for Building and Other Structures, ASCE/SEI 7-10. American Society of Civil Engineers, RestonBenavent-Climent A (2007) Seismic behavior of RC side beam-column connections under dynamic loading. J Earthquake Eng 11:493–511Benavent-Climent A, Zahran R (2010) An energy-based procedure for the assessment of seismic capacity of existing frames: application to RC wide beam systems in Spain. Soil Dyn Earthq Eng 30:354–367Benavent-Climent A, Cahís X, Zahran R (2009) Exterior wide beam-column connections in existing RC frames subjected to lateral earthquake loads. Eng Struct 31:1414–1424Benavent-Climent A, Cahís X, Vico JM (2010) Interior wide beam-column connections in existing RC frames subjected to lateral earthquake loading. Bull Earthq Eng 8:401–420BHRC (2004) Iranian Code of Practice for Seismic Resistant Design of Buildings. Standard Nº 2800, 3rd edn. Building and Housing Research Center, TehranBorzi B, Elnashai AS (2000) Refined force reduction factors for seismic design. Eng Struct 22:1244–1260Borzi B, Pinho R, Crowley H (2008) Simplified pushover-based vulnerability analysis for large-scale assessment of RC buildings. Eng Struct 30:804–820BSI (2004) Eurocode 2: Design of concrete structures: Part 1-1: General rules and rules for buildings. British Standards Institutions, LondonCalvi GM (1999) A displacement-based approach for vulnerability evaluation of classes of buildings. J Earthquake Eng 3(3):411–438CDSC (1994) Seismic construction code, NCSR-94. Committee for the Development of Seismic Codes, Spanish Ministry of Construction, Madrid, Spain (in Spanish)CDSC (2002) Seismic construction code, NCSE-02. Committee for the Development of Seismic Codes, Spanish Ministry of Construction, Madrid, Spain (in Spanish)CEN (2004) Eurocode 8: design of structures for earthquake resistance—part 1: general rules, seismic actions and rules for buildings. European Standard EN 1998-1:2003—Comité Européen de Normalisation, Brussels, BelgiumCEN (2005) Eurocode 8: design of structures for earthquake resistance—part 3: assessment and retrofitting of buildings. European Standard EN 1998-1:2005—Comité Européen de Normalisation, Brussels, BelgiumCheung PC, Paulay T, Park R (1991) Mechanisms of slab contributions in beam-column subassemblages. ACI Spec Publ 123Cosenza E, Manfredi G, Polese M, Verderame GM (2005) A multilevel approach to the capacity assessment of existing RC buildings. J Earthquake Eng 9(1):1–22Crowley H, Pinho R (2010) Revisiting Eurocode 8 formulae for periods of vibration and their employment in linear seismic analysis. Earthquake Eng Struct Dynam 39:223–235CS.LL.PP (2009) Instructions for the application of the technique code for the Constructions. Official Gazette of the Italian Republic, 47, Regular Supplement no. 27 (in Italian)De Luca F, Vamvatsikos D, Iervolino I (2013) Near-optimal piecewise linear fits of static pushover capacity curves for equivalent SDOF analysis. Earthquake Eng Struct Dynam 42(4):523–543De Luca F, Verderame GM, Gómez-Martínez F, Pérez-García A (2014) The structural role played by masonry infills on RC building performances after the 2011 Lorca, Spain, earthquake. Bull Earthq Eng 12(5):1999–2026Decanini LD, Mollaioli F (2000) Analisi di vulnerabilità sismica di edifici in cemento armato pre-normativa. In: Cosenza E (ed) Comportamento sismico di edifici in cemento armato progettati per carichi verticali. CNR—Gruppo Nazionale per la Difesa dei Terremoti, Rome (in Italian)Dolšek M, Fajfar P (2004) IN2—a simple alternative for IDA. In: Proceedings of the 13th World conference on Earthquake Engineering. August 1–6, Vancouver, Canada. Paper 3353Domínguez D, López-Almansa F, Benavent-Climent A (2014) Comportamiento para el terremoto de Lorca de 11-05-2011, de edificios de vigas planas proyectados sin tener en cuenta la acción sísmica. Informes de la Construcción 66(533):e008 (in Spanish)Domínguez D, López-Almansa F, Benavent-Climent A (2016) Would RC wide-beam buildings in Spain have survived Lorca earthquake (11-05-2011)? Eng Struct 108:134–154Dönmez C (2013) Seismic Performance of Wide-Beam Infill-Joist Block RC Frames in Turkey. J Perform Constr Facil 29(1):04014026Fadwa I, Ali TA, Nazih E, Sara M (2014) Reinforced concrete wide and conventional beam-column connections subjected to lateral load. Eng Struct 76:34–48Fardis MN (2009) Seismic design, assessment and retrofitting of concrete, Buildings edn. Springer, LondonGentry TR, Wight JK (1992) Reinforced concrete wide beam-column connections under earthquake-type loading. Report no. UMCEE 92-12. Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USAGómez-Martínez F (2015) FAST simplified vulnerability approach for seismic assessment of infilled RC MRF buildings and its application to the 2011 Lorca (Spain) earthquake. Ph.D. Thesis, Polytechnic University of Valencia, SpainGómez-Martínez F, Pérez García A, De Luca F, Verderame GM (2015a) Comportamiento de los edificios de HA con tabiquería durante el sismo de Lorca de 2011: aplicación del método FAST. Informes de la Construcción 67(537):e065 (in Spanish)Gómez-Martínez F, Pérez-García A, Alonso Durá A, Martínez Boquera A, Verderame GM (2015b) Eficacia de la norma NCSE-02 a la luz de los daños e intervenciones tras el sismo de Lorca de 2011. In: Proceedings of Congreso Internacional sobre Intervención en Obras Arquitectónicas tras Sismo: L’Aquila (2009), Lorca (2011) y Emilia Romagna (2012), May 13–14, Murcia, Spain (in Spanish)Gómez-Martínez F, Verderame GM, De Luca F, Pérez-García A, Alonso-Durá, A (2015c). High ductility seismic performances of wide-beam RC frames. In; XVI Convegno ANIDIS. September 13–17, L'Aquila, ItalyHawkins NM, Mitchell D (1979) Progressive collapse of flat plate structures. 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Aerosol number fluxes and concentrations over a southern European urban area

Although cities are an important source of aerosol particles, aerosol number flux measurements over urban areas are scarce. These measurements are however important as they can allow us to identify the different sources/sinks of aerosol particles and quantify their emission contributions. Therefore, they can help us to understand the aerosol impacts on human health and climate, and to design effective mitigation strategies through the reduction of urban aerosol emissions. In this work we analyze the aerosol number concentrations and fluxes for particles with diameters larger than 2.5 nm measured by eddy covariance technique at an urban area (Granada city, Spain) from November 2016 to April 2018. This is the first study of particle number flux in an urban area in the Iberian Peninsula and is one of the few current studies that report long-term aerosol number flux measurements. The results suggest that, on average, Granada urban area acted as a net source for atmospheric aerosol particles with median particle number flux of 150 x 10(6) m(-2) s(-1). Downward negative fluxes were observed in only 12% of the analyzed data, and most of them were observed during high aerosol load conditions. Both aerosol number fluxes and concentrations were maximum in winter and 50% larger than those measured in summer due to the increased emissions from domestic heating, burning of residual agricultural waste in the agricultural area surrounding the site, as well as to the lower aerosol dilution effects during winter. The analysis of the seasonal diurnal variability of the aerosol number concentration revealed the significant impact of traffic emissions on aerosol population over Granada urban area in all seasons. It also shows the impact of domestic heating and agricultural waste burning emissions in winter as well as the influence of new particle formation processes in summer and spring seasons. Closer analysis by wind sector demonstrated that both aerosol concentrations and fluxes from urban sector (where high density of anthropogenic sources is located) were lower than those from rural sector (which includes agricultural area but also the main highway of the city). This evidences the strong impact of aerosol emissions from traffic circulating on the highway on aerosol population over our measurement site.Peer reviewe

Correction of a lunar-irradiance model for aerosol optical depth retrieval and comparison with a star photometer

The emergence of Moon photometers is allowing measurements of lunar irradiance over the world and increasing the potential to derive aerosol optical depth (AOD) at night-time, which is very important in polar areas. Actually, new photometers implement the latest technological advances that permit lunar-irradiance measurements together with classical Sun photometry measurements. However, a proper use of these instruments for AOD retrieval requires accurate time-dependent knowledge of the extraterrestrial lunar irradiance over time due to its fast change throughout the Moon's cycle. This paper uses the RIMO (ROLO Implementation for Moon's Observation) model (an implementation of the ROLO – RObotic Lunar Observatory – model) to estimate the AOD at night-time assuming that the calibration of the solar channels can be transferred to the Moon by a vicarious method. However, the obtained AOD values using a Cimel CE318-T Sun–sky–Moon photometer for 98 pristine nights with low and stable AOD at the Izaña Observatory (Tenerife, Spain) are not in agreement with the expected (low and stable) AOD values estimated by linear interpolations from daytime values obtained during the previous evening and the following morning. Actually, AOD calculated using RIMO shows negative values and with a marked cycle dependent on the optical air mass. The differences between the AOD obtained using RIMO and the expected values are assumed to be associated with inaccuracies in the RIMO model, and these differences are used to calculate the RIMO correction factor (RCF). The RCF is a proposed correction factor that, multiplied by the RIMO value, gives an effective extraterrestrial lunar irradiance that provides AOD closer to the expected values. The RCF varies with the Moon phase angle (MPA) and with wavelength, ranging from 1.01 to 1.14, which reveals an overall underestimation of RIMO compared to the lunar irradiance. These obtained RCF values are modelled for each photometer wavelength to a second-order polynomial as a function of MPA. The AOD derived by this proposed method is compared with the independent AOD measurements obtained by a star photometer at Granada (Spain) for 2 years. The mean of the Moon–star AOD differences is between −0.015 and −0.005, and the standard deviation (SD) is between 0.03 and 0.04 (which is reduced to about 0.01 if 1 month of data affected by instrumental issues is not included in the analysis) for 440, 500, 675, and 870 nm; however, for 380 nm, the mean and standard deviation of these differences are higher. The Moon–star AOD differences are also analysed as a function of MPA, showing no significant dependence.This research has been supported by the Spanish Ministry of Science, Innovation and Universities (grant no. RTI2018-097864-b-I00); the Spanish Ministry of Economy and Competitiveness (grant nos. CGL2016-81092-R and CGL2017-90884-REDT); the European Union's Horizon 2020 research and innovation programme (grant no. ACTRIS IMP 871115); and the Andalusia Regional Government (grant no. P18-RT-3820)