•Performance of shear wall buildings was improved by increasing the lateral stiffness.•Larger stiffness reduced the probability of exceeding life safety limit state.•Larger stiffness reduced the ...probability of collapse for the same IM.•Larger stiffness increased the probability of collapse in 50 years.•Displacement ductility increased when the stiffness of the building decreased.
This study assesses the effect of the stiffness on the seismic performance of residential shear wall buildings designed according to current Chilean regulations, including DS60 and DS61. Specifically, the paper focuses on the effect of stiffness on the building overstrength, displacement ductility, fragility for Life Safety (LS) and collapse limit states, as well as the probability of achieving these two limits states in 50 years. The seismic performance is assessed for a group of four 20-story residential shear wall buildings archetypes located in Santiago. Walls were modeled using the multiple vertical line element model (MVLEM) with inelastic hysteretic materials for the vertical elements, and a linear-elastic shear behavior. Pushover analyses were considered to estimate the buildings overstrength and displacement ductility, while incremental dynamic analyses were performed to estimate fragility curves. A probabilistic seismic hazard analysis, which considered the seismicity of Chile central zone, was performed to estimate the probability of achieving the two limits states in 50 years. The results show that an increase in the stiffness reduces the chance of exceeding the LS and collapse limit states for the same intensity level. Additionally, the probabilistic seismic hazard analysis shows that, when the stiffness increases, the probability of reaching the LS limit state in 50 years also decreases. Counterintuitively, the probability of collapse in 50 years increases as the stiffness increases, due to the considered seismic hazard and the design requirements. Since society is moving towards resilient structural designs that minimize damage, disruption and economic losses, it is concluded that the performance of reinforced concrete shear wall buildings is improved by increasing the stiffness.
IntroductionBipolar disorder (BD) is a chronic and recurrent mental condition characterized by mood fluctuations between hypomania or mania and depression, with high level of burden and mortality ...rates (Hayes et al., 2015). Subsyndromal mood symptoms, including residual depression, mania and/or anxiety, are major risk factors for episodic relapses after mood stabilisation (Samalin et al., 2016). A psychological protective mechanism against the occurrence of these maladaptative mood symptoms is dispositional mindfulness (DM). DM refers to paying purposeful attention to present moment experiences with a curious, non-judgmental and accepting attitude (Radford et al., 2014). DM has been barely assessed in BD and there is very little evidence on the relationship between DM, residual mood symptoms and quality of lifeObjectivesTo explore associations between DM, residual mood symptoms and quality of life in individuals with BDMethodsAfter informed consent, a total of 94 adults (Mean age= 45.57 years, 41.50% Male) with diagnosis of BD according to DSM-5 criteria, in full or partial remission,were recruited from the Bipolar and Depressive Disorders Unit at the Hospital Clinic of Barcelona. The ethical committee approved this study. Dispositional mindfulness was assessed using the Mindfulness Attention Awareness Scale (MAAS).The presence of residual depressive symptoms was assessed with the Hamilton Depression Rating Scale (HDRS), residual mania symptoms were assessed with the Young Mania Rating Scale(YMRS), and anxiety symptoms were assessed with the Hamilton Anxiety Rating Scale (HAM-A). The subjective quality of life was assessed with the Quality of Life in Bipolar Disorder Questionnaire (QoL-BD). Pearson correlations were carried out and the level of significance was set at p<0.05ResultsDM was negatively related to residual depressive symptoms (r= -0.283; p=0.009) and to anxiety symptoms (r=-0.345; p<0.001), and positively related to quality of life (r=0.433; p<0.001), but not related to residual manic symptoms in BDConclusionsOur preliminary data suggest that BD patients with higher levels of DM may experience less depressive and anxiety subsyndromal symptoms and perceived higher quality of life. No associations were detected regarding mania symptoms. These findings support the use of mindfulness training as an adjunct therapy to pharmacotherapy to reduce residual mood symptoms and improve quality of life in patients with BDDisclosure of InterestNone Declared
The Infinium EPIC array measures the methylation status of > 850,000 CpG sites. The EPIC BeadChip uses a two-array design: Infinium Type I and Type II probes. These probe types exhibit different ...technical characteristics which may confound analyses. Numerous normalization and pre-processing methods have been developed to reduce probe type bias as well as other issues such as background and dye bias.
This study evaluates the performance of various normalization methods using 16 replicated samples and three metrics: absolute beta-value difference, overlap of non-replicated CpGs between replicate pairs, and effect on beta-value distributions. Additionally, we carried out Pearson's correlation and intraclass correlation coefficient (ICC) analyses using both raw and SeSAMe 2 normalized data.
The method we define as SeSAMe 2, which consists of the application of the regular SeSAMe pipeline with an additional round of QC, pOOBAH masking, was found to be the best performing normalization method, while quantile-based methods were found to be the worst performing methods. Whole-array Pearson's correlations were found to be high. However, in agreement with previous studies, a substantial proportion of the probes on the EPIC array showed poor reproducibility (ICC < 0.50). The majority of poor performing probes have beta values close to either 0 or 1, and relatively low standard deviations. These results suggest that probe reliability is largely the result of limited biological variation rather than technical measurement variation. Importantly, normalizing the data with SeSAMe 2 dramatically improved ICC estimates, with the proportion of probes with ICC values > 0.50 increasing from 45.18% (raw data) to 61.35% (SeSAMe 2).
•A Chilean code-conforming reinforced concrete office building is designed.•Incremental dynamic analyses of the building are performed using 45 ground motions.•Two collapse fragility curves and two ...seismic hazard curves are proposed.•Estimated mean annual frequencies of collapse were in the order of 10−5–10−4.•Estimated probabilities of collapse in 50 years were in the order of 0.1–0.7%
Several code-conforming reinforced concrete buildings were severely damaged during the 2010 moment magnitude (Mw) 8.8 Chile earthquake, raising concerns about their real collapse margin. Although critical updates were introduced into the Chilean design codes after 2010, guidelines for collapse risk assessment of Chilean buildings remain insufficient. This study evaluates the collapse potential of a typical dual system (shear walls and moment frames) office building in Santiago. Collapse fragility functions were obtained through incremental dynamic analyses using a state-of-the-art finite element model of the building. Site-specific seismic hazard curves were developed, which explicitly incorporated epistemic uncertainty, and combined with the collapse fragility functions to estimate the mean annual frequency of collapse (λc) values and probabilities of collapse in 50-years (Pc(50)). Computed values of λc and Pc(50) were on the order of 10−5–10−4, and 0.1–0.7%, respectively, consistent with similar studies developed for buildings in the US. The results also showed that the deaggregation of λc was controlled by small to medium earthquake intensities and that different models of the collapse fragility functions and hazard curves had a non-negligible effect on λc and Pc(50), and thus, propagation of uncertainty in risk assessment problems must be adequately taken into account.
Global buckling of slender walls, reported only in a few laboratory tests before 2010, became a critical issue in design of reinforced concrete buildings after it was observed following the 2010 Mw ...8.8 Chile earthquake and the 2011 Mw 6.3 New Zealand earthquake. Researchers have proposed theoretical buckling models based on prismatic columns subjected to uniform tension/compression cycles, where the key parameters are slenderness ratio, number of curtains of reinforcement, and maximum tensile strain before buckling during load reversal. These models have shown sufficient accuracy in comparison with laboratory tests on columns under such loading conditions. However, buckling in walls is more complex because of variation of strains through the wall depth and variation of moment along the wall height. Nonlinear finite elements are used to evaluate the effects of these more complex loadings on buckling of wall boundary elements. Analyses showed that the maximum tensile strain (averaged over the wall out-of-plane unsupported height) required to buckle the wall during load reversal does not depend on the moment variation along the wall height. Moreover, for typical wall lengths, the wall boundary behaves like an isolated column subjected to axial force cycles, with minimal apparent bracing provided by the wall web. This allows to analyze a broad range of practical cases for buckling susceptibility using simplified approaches based on buckling models of axially loaded columns.
The purpose of seismic provisions included in modern building codes is to obtain a satisfactory structural performance of buildings during earthquakes. However, in the United States and elsewhere, ...there are large inventories of buildings designed and constructed several decades ago, under outdated building codes. Some of these buildings are classified as non-ductile buildings. Currently, under the ATC-78 project, a methodology is being developed to identify seismically hazardous frame–wall buildings through a simple procedure that does not require full nonlinear analyses by the responsible engineer. This methodology requires the determination of the controlling plastic collapse mechanism, the base shear strength, and the ratio between the story drift ratio and the roof drift ratio, called parameter
α
, at collapse level. The procedure is calibrated with fully inelastic nonlinear analyses of archetype buildings. In this paper we first introduce an efficient scheme for modeling frame–wall buildings using the software OpenSees. Later, the plastic collapse mechanism, the base shear strength, and values of
α
are estimated from nonlinear static and dynamic analyses considering a large suite of ground-motion records that represent increasing hazard levels. The analytical experiment included several frame–wall combinations in 4 and 8-story buildings, intended to represent a broad range of conditions that can be found in actual buildings, where the simplified methodology to evaluate the risk of collapse can be applicable. Analysis results indicate that even walls of modest length may positively modify the collapse mechanism of nonductile bare frames preventing soft story failures.
Helicoverpa armigera
(Hübner) has attacked several economically important crops since it was first reported in Brazil in 2013. Because insecticides have been used intensively to control
H. armigera
, ...resistant populations have been detected more frequently. One alternative to insecticides is the use of biological control with egg parasitoids from the family Trichogrammatidae (Hymenoptera). The present study evaluated the use of different species and strains of these parasitoids to control
H. armigera
in soybean. Five strains of
Trichogramma pretiosum
(Riley): RV (Rio Verde, Goiás, Brazil), SO (Sorriso, Mato Grosso, Brazil), 47A (Irvine, CA, USA), PR (Colombo, Paraná, Brazil), and AN (Anhumas, São Paulo, Brazil), and
Trichogrammatoidea annulata
(De Santis) denominated TR, from Anhumas, were used. The following parasitoid biological parameters were evaluated: parasitism rates (%), offspring viability (%) number of parasitoids emerged per egg, egg-adult duration (days), female longevity, and offspring sex ratio. Strain RV of
T. pretiosum
from central Brazil performed best.
Diffusion MRI data are generally acquired using hyperpolarized gases during patient breath-hold, which yields a compromise between achievable image resolution, lung coverage, and number of b-values. ...In this paper, we propose a novel method that accelerates the acquisition of diffusion MRI data by undersampling in both the spatial and b-value dimensions and incorporating knowledge about signal decay into the reconstruction (SIDER). SIDER is compared with total variation(TV) reconstructionby assessing its effect on both the recovery of ventilation images and the estimated mean alveolar dimensions (MADs). Both methods are assessed by retrospectively undersampling diffusion data sets (n=8) of healthy volunteers and patients.
Abstract
The objective was to evaluate the effects of a specific strain of live yeast (LY) on growth performance, fermentation parameters, feed efficiency, and bacterial communities in the rumen of ...growing cattle fed low-quality hay. In experiment (exp.) 1, 12 Droughtmaster bull calves (270 ± 7.6 kg initial body weight BW) were blocked by BW into two groups, allocated individually in pens, and fed ad libitum Rhodes grass hay (8.4% of crude protein CP) and 300 g/bull of supplement (52% CP) without (Control) or with LY (8 × 109 colony-forming unit CFU/d Saccharomyces cerevisiae CNCM I-1077; Lallemand Inc., Montreal, Canada) for 28 d, followed by 7 d in metabolism crates. Blood and rumen fluid were collected before feeding and 4 h after feeding. In exp. 2, for assessment of growth performance, 48 Charbray steers (329 ± 20.2 kg initial BW) were separated into two blocks by initial BW and randomly allocated into 12 pens. The steers were fed Rhodes grass hay (7.3% CP) and 220 g/steer of supplement (60% CP) without or with LY (8 × 109 CFU/d) for 42 d, after a 2-wk adaptation period. In exp. 1, fiber digestibility was calculated from total fecal collection, and, in exp 2, indigestible neutral detergent fiber (NDF) was used as a marker. Inclusion of LY increased (P = 0.03) NDF intake by 8.3% in exp. 1, without affecting total tract digestibility. No changes were observed in microbial yield or in the efficiency of microbial production. There was a Treatment × Time interaction (P < 0.01) for the molar proportion of short-chain fatty acids, with LY increasing propionate before feeding. Inclusion of LY decreased rumen ammonia 4 h after feeding (P = 0.03). The addition of LY reduced rumen bacterial diversity and the intraday variation in bacterial populations. Relative populations of Firmicutes and Verrucomicrobia varied over time (P < 0.05) only within the Control group. At the genus level, the relative abundance of an unclassified bacterial genus within the order Clostridiales, a group of cellulolytic bacteria, was reduced from 0 to 4 h after feeding in the Control group (P = 0.02) but not in the LY group (P = 1.00). During exp. 2, LY tended to increase average daily gain (ADG) (P = 0.08) and feed efficiency (P = 0.10), with no effect on NDF intake or digestibility. In conclusion, S. cerevisiae CNCM I-1077 reduced the intraday variation of rumen bacteria and increased the amount of NDF digested per day. These observations could be associated with the tendency of increased ADG and feed efficiency in growing cattle fed a low-quality forage.
Today (year 2020), the globally recognized problem of arsenic (As) contamination of water resources and other environments at toxic levels has been reported in all of the 20 Latin American countries. ...The present review indicates that As is prevalent in 200 areas across these countries. Arsenic is naturally released into the environment and mobilized from geogenic sources comprising: (i) volcanic rocks and emissions, the latter being transported over thousands of kilometers from the source, (ii) metallic mineral deposits, which get exposed to human beings and livestock through drinking water or food chain, and (iii) As-rich geothermal fluids ascending from deep geothermal reservoirs contaminate freshwater sources. The challenge for mitigation is increased manifold by mining and related activities, as As from mining sites is transported by rivers over long distances and even reaches and contaminates coastal environments. The recognition of the As problem by the authorities in several countries has led to various actions for remediation, but there is a lack of long-term strategies for such interventions. Often only total As concentration is reported, while data on As sources, mobilization, speciation, mobility and pathways are lacking which is imperative for assessing quality of any water source, i.e. public and private.
PDF
