Soil-structure interaction effects in analysis of seismic fragility of bridges using an intensity-based ground motion selection procedure

The paper focuses on the effects of Soil-Structure Interaction (SSI) in seismic fragility analysis of reinforced concrete (RC) bridges, considering the vulnerability of multiple critical components of the bridge and different modelling approaches for soil-foundation and bridge-embankment interactions. A two-step procedure, based on the introduction of springs and dashpots at the pier foundations and the abutment to account for inertial and kinematic SSI effects, is incorporated into a component-based methodology for the derivation of bridge-specific fragility curves. The proposed methodology is applied for quantifying the fragility of a typical highway overpass at both the component and system level, while the effect of alternative procedures (of varying complexity) for modelling foundation and abutment boundary conditions is critically assessed. The rigorous SSI modelling method is compared with simpler methods and the results show that consideration of SSI may only slightly affect the probability of system failure, depending on the modelling assumptions made. However, soil-structure interaction may have a notable effect on component fragility, especially for the more critical damage states. This is an observation that is commonly overlooked when assessing the structural performance at the system level and can be particularly important when component fragility is an issue, e.g. when designing a retrofit scheme

Gabapentin for the hemodynamic response to intubation: systematic review and meta-analysis

Purpose Endotracheal intubation is the gold standard for securing the airway before surgery. Nevertheless, this procedure can produce an activation of the sympathetic nervous system and result in a hemodynamic response which, in high-risk patients, may lead to cardiovascular instability and myocardial ischemia. The aim of this review was to evaluate whether gabapentin can attenuate this response and whether such an attenuation could translate into reduced myocardial ischemia and mortality. Source We searched MEDLINE®, EMBASE™, CINAHL, AMED, and unpublished clinical trial databases for randomized-controlled trials that compared gabapentin with control, fentanyl, clonidine, or beta blockers for attenuating the hemodynamic response to intubation. Primary outcomes were mortality, myocardial infarction, and myocardial ischemia. Secondary outcomes were hemodynamic changes following intubation. Principal findings We included 29 randomized trials with only two studies at low risk of bias. No data were provided for the primary outcomes and no studies included high-risk patients. The use of gabapentin resulted in attenuation in the rise in mean arterial blood pressure [mean difference (MD), −12 mmHg; 95% confidence interval (CI), −17 to −8] and heart rate (MD, −8 beats·min−1; 95% CI, −11 to −5) one minute after intubation. Gabapentin also reduced the risk of hypertension or tachycardia requiring treatment (risk ratio, 0.15; 95% CI, 0.05 to 0.48). Data were limited on adverse hemodynamic events such as bradycardia and hypotension. Conclusion It remains unknown whether gabapentin improves clinically relevant outcomes such as death and myocardial infarction since studies failed to report on these. Nevertheless, gabapentin attenuated increases in heart rate and blood pressure following intubation when compared with the control group. Even so, the studies included in this review were at potential risk of bias. Moreover, they did not include high-risk patients or report adverse hemodynamic outcomes. Future studies are required to address these limitations

Inhibitory effects of high pressure processing on Photobacterium phosphoreum and Morganella psychrotolerans in vacuum packed herring (Clupea harengus)

Herring fillets were inoculated with Photobacterium phosphoreum and Morganella psychrotolerans, vacuum packed and subjected to high-pressure processing (HPP) treatment (100, 200, 300, and 500 MPa for 5 min) or left untreated as controls. The samples were stored at 4 ± 1 °C up to 21 days, and subjected to microbial quality evaluation. The results revealed that 500 MPa pressure treatment significantly (p <.05) delayed the growth of P. phosphoreum and M. psychrotolerans until 12th and 7th days of the storage, respectively, as compared to the controls. Total psychrophilic bacterial growth was not observed until 19th day of the storage in 500 MPa pressure treated herring fillets inoculated with both P. phosphoreum and M. psychrotolerans. In the samples inoculated with P. phosphoreum and treated with 500 MPa pressure, H2S-producing bacteria were not observed during 14 days for M. psychrotolerans, while for entire storage period for P. phosphoreum. Practical applications: High-pressure processing (HPP) is a nonthermal preservation technique that depends on the magnitude of the pressure, processing time/temperature, and product characteristics that allows microbial inactivation at low temperatures with mild changes in texture, color, and flavor of the product as compared to the conventional technologies. Targeted inhibition of specific spoilage bacteria rather than more drastic means inhibiting the total microflora may therefore be a useful approach to achieving lower rates of spoilage and may thereby extend shelf life. In this study, HPP treatment up to 200 MPa did not significantly (p >.05) affect the microbial growth of vacuum-packed herring fillets, but further higher pressure levels (300–500 MPa) were effective to inhibit the growth of microorganisms. Overall, the findings of this study suggested that HPP application of 300 MPa and above could help to industry for commercial production of microbiologically free fish and fish products. © 2018 Wiley Periodicals, IncDeutscher Akademischer Austauschdienst Deutscher Akademischer AustauschdienstDeutscher Akademischer Austauschdienst; Scientific and Technological Research Council of TurkeyThis research was supported by the Scientific and Technological Research Council of Turkey (TUBITAK) and Deutscher Akademischer Austauschdienst (DAAD). The authors thank to the management and the staff of Deutsches Institut für Lebensmitteltechnik (German Institute of Food Technologies) for providing opportunity to work and infrastructure

Inhibitory effects of high pressure treatment on microbial growth and biogenic amine formation in marinated herring (Clupea harengus) inoculated with Morganella psychrotolerans

Inhibitory effects of high pressure processing (HPP) on the biogenic amine formation (histamine, tyramine, putrescine and cadaverine) in marinated herring fillets (2% acetic acid+8% NaCl; or 4% acetic acid+8% NaCl solutions) were investigated. Marinated fillets were inoculated with M. psychrotolerans followed by vacuum-packaging and HPP treatment at 100, 300 and 500 MPa for 5 and 10 min. One batch was left untreated for each marination group and the batches were stored at 4 °C for 3 months. HPP in combination with 4% acetic acid had a strong inhibitory effect on the growth of M. psychrotolerans, since there was no growth in samples treated with 300 MPa for 10 min and 500 MPa for 5, 10 min. Psychrophilic bacteria growth was not detected in samples marinated with 4% acetic acid and treated with 500 MPa H2S-producing bacteria were not observed in marinated herring during the storage period. Histamine and cadaverine formation were not observed in the samples marinated with 4% acetic acid along the storage. Taken together, the findings of this research might be helpful to enhance the safety of consumption of marinated herring. © 2018 Elsevier LtdDeutscher Akademischer Austauschdienst Firat University Scientific Research Projects Management UnitThis research was supported by the Scientific and Technological Research Council of Turkey (TUBITAK), Deutscher Akademischer Austauschdienst (DAAD) and The Scientific Research Projects Administration Unit of Akdeniz University under project no. FDK-2015-273 . The authors thank to management and staff of Deutsches Institut für Lebensmitteltechnik (German Institute of Food Technologies) for providing opportunity to work and infrastructure

Changes in vision related quality of life in patients with diabetic macular edema: ranibizumab or laser treatment?

PMID = 2581717