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Response Measures (response + measure)
Selected AbstractsA vector-valued ground motion intensity measure consisting of spectral acceleration and epsilonEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 10 2005Jack W. Baker Abstract The ,strength' of an earthquake ground motion is often quantified by an Intensity Measure (IM), such as peak ground acceleration or spectral acceleration at a given period. This IM is used to predict the response of a structure. In this paper an intensity measure consisting of two parameters, spectral acceleration and epsilon, is considered. The IM is termed a vector-valued IM, as opposed to the single parameter, or scalar, IMs that are traditionally used. Epsilon (defined as a measure of the difference between the spectral acceleration of a record and the mean of a ground motion prediction equation at the given period) is found to have significant ability to predict structural response. It is shown that epsilon is an indicator of spectral shape, explaining why it is related to structural response. By incorporating this vector-valued IM with a vector-valued ground motion hazard, we can predict the mean annual frequency of exceeding a given value of maximum interstory drift ratio, or other such response measure. It is shown that neglecting the effect of epsilon when computing this drift hazard curve leads to conservative estimates of the response of the structure. These observations should perhaps affect record selection in the future. Copyright © 2005 John Wiley & Sons, Ltd. [source] Probabilistic seismic demand analysis of controlled steel moment-resisting frame structuresEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 12 2002Luciana R. Barroso Abstract This paper describes a proposed methodology, referred to as probabilistic seismic control analysis, for the development of probabilistic seismic demand curves for structures with supplemental control devices. The resulting curves may be used to determine the probability that any response measure, whether for a structure or control device, exceeds a pre-determined allowable limit. This procedure couples conventional probabilistic seismic hazard analysis with non-linear dynamic structural analyses to provide system specific information. This method is performed by evaluating the performance of specific controlled systems under seismic excitations using the SAC Phase II structures for the Los Angeles region, and three different control-systems: (i) base isolation; (ii) linear viscous brace dampers; and (iii) active tendon braces. The use of a probabilistic format allows for consideration of structural response over a range of seismic hazards. The resulting annual hazard curves provide a basis for comparison between the different control strategies. Results for these curves indicate that no single control strategy is the most effective at all hazard levels. For example, at low return periods the viscous system has the lowest drift demands. However, at higher return periods, the isolation system becomes the most effective strategy. Copyright © 2002 John Wiley & Sons, Ltd. [source] Initial testing of topotecan by the pediatric preclinical testing program,PEDIATRIC BLOOD & CANCER, Issue 5 2010Hernan Carol PhD Abstract Background Topotecan is a small molecule DNA topoisomerase I poison, that has been successful in clinical trials against pediatric solid tumors and leukemias. Topotecan was evaluated against the Pediatric Preclinical Testing Program (PPTP) tumor panels as part of a validation process for these preclinical models. Procedures In vivo three measures of antitumor activity were used: (1) an objective response measure modeled after the clinical setting; (2) a treated to control (T/C) tumor volume measure; and (3) a time to event (fourfold increase in tumor volume for solid tumor models, or ,25% human CD45+ cells in the peripheral blood for acute lymphoblastic leukemia, ALL models) measure based on the median event-free survival (EFS) of treated and control animals for each xenograft. Results Topotecan inhibited cell growth in vitro with IC50 values between 0.71 and 489,nM. Topotecan significantly increased EFS in 32 of 37 (87%) solid tumor xenografts and in all 8 of the ALL xenografts. Seventy-five percent of solid tumors met EFS T/C activity criteria for intermediate (n,=,17) or high activity (n,=,7). Objective responses were noted in eight solid tumor xenografts (Wilms, rhabdomyosarcoma, Ewing sarcoma, neuroblastoma). Among the six neuroblastomas, three achieved a PR. For the ALL panel, two maintained CRs, three CRs, and two PRs were observed. Conclusions Topotecan demonstrated broad activity in vitro and in vivo against both the solid tumor and ALL panels, with significant tumor growth delay generated in all the panels. These results further demonstrate the validity of the PPTP panel for preclinical testing of new drugs. Pediatr Blood Cancer 2010;54:707,715. © 2009 Wiley-Liss, Inc. [source] The systematic approach to flooding problems,IRRIGATION AND DRAINAGE, Issue S1 2006J. (Hans) van Duivendijk maîtrise des crues; mesures non-structurelles; gestion des inondations Abstract Since 1987 one of the working groups of the International Commission on Irrigation and Drainage (ICID) has, inter alia, been preparing two manuals concerning approaches to flooding problems. The Manual on Non-Structural Approaches to Flood Management was issued in 1999 while the Manual on the Planning of Structural Approaches to Flood Management has been issued recently (2005). In this paper a broad outline of both manuals is presented. The first manual describes in detail the various planning and response measures in flood management, which are known as non-structural measures. The latter are measures which alter the exposure of life and property to flooding but do not change the flood(ing) phenomenon as such. The said planning and response measures comprise such actions as floodplain land use management, flood forecasting and warning, flood fighting, flood proofing, etc. It is explained that such measures are sometimes the only ones feasible in the prevailing circumstances and that, moreover, non-structural measures should always be added to the so-called structural measures if the latter are considered feasible (i.e. feasible from a technical, economic, socio-economic and ecological point of view). In the second manual a methodology is presented for the planning of structural measures. This type of measure alters the physical characteristics of the floods and in this connection one must think of the operation of flood storage reservoirs, upstream catchment management, modification to river channels, construction of levees, special flood diversion channels (bypasses) and operation of hydraulics works. The idea behind this methodology is that it is difficult for planners and decision makers to select the appropriate flood protection system for a given situation including a range of possible floods if the problem is not approached in a systematic manner. Copyright © 2006 John Wiley & Sons, Ltd. Depuis 1987 un des groupes de travail de la CIID prépare, entre autres, deux manuels sur la manière d'approcher les problèmes d'inondation. Le ,Manuel d'approche non-structurelle de la gestion des crues' a été publié en 1999, tandis que le ,Manuel de la planification de l'approche structurelle de la gestion des crues' a été publié plus récemment (2005). Le présent article présente une vue d'ensemble de ces deux manuels. Le premier manuel donne une description détaillée des différentes mesures de préparation et de réponse à la gestion des crues, connues comme étant non-structurelles. Ces mesures changent l'exposition de la vie et des propriétés aux inondations mais ne modifient pas le phénomène proprement dit des crues et des inondations. Elles comprennent des actions telles que la gestion de l'espace dans les plaines d'inondations, les prévisions et alertes, la lutte contre les crues, la protection contre les inondations, etc. On y explique que ces mesures sont parfois les seules faisables dans les circonstances données et que, en outre, des mesures non-structurelles devraient toujours être ajoutées aux mesures dites structurelles si ces dernières sont considérées comme faisables (c'est-à-dire faisables d'un point de vue technique, économique, socio-économique et écologique). Dans le second manuel une méthodologie est présentée pour la planification des mesures structurelles. Ce type de mesures modifie les caractéristiques physiques des crues, comme par exemple réservoirs d'écrétage de crue, gestion des hauts bassins, modification des lits des fleuves, construction de digues, canaux spéciaux de déviation des crues (courts circuits) et fonctionnement d'ouvrages hydrauliques. L'idée qui est derrière cette méthodologie est qu'il est difficile aux planificateurs et aux décideurs de choisir le système de protection contre les crues correspondant exactement à une situation comprenant une large gamme d'inondations possibles si le problème n'est pas approché de manière systématique. Copyright © 2006 John Wiley & Sons, Ltd. [source] ALDH2 Status, Alcohol Expectancies, and Alcohol Response: Preliminary Evidence for a Mediation ModelALCOHOLISM, Issue 11 2001Denis M. McCarthy Background: A genetic variant in the alcohol-metabolizing enzyme (aldehyde dehydrogenase;ALDH2*2 allele), common in individuals of Asian heritage, has been associated with both physiologic response to alcohol and alcohol consumption. Prior research has also demonstrated that those with ALDH2*2 alleles have lower positive alcohol expectancies than those without these alleles. This preliminary study was designed to test whether the level of response to alcohol is the mechanism by which ALDH2 status may affect alcohol expectancies. Methods: Data were collected from 32 Asian American college students (14 women and 18 men). By use of a randomized, double-blind design, participants were administered oral placebo and alcohol at separate laboratory sessions. Data included blood tests to establish ALDH2 status, questionnaire measures of demographic information and alcohol expectancy, and several physiologic measures collected after placebo and alcohol administration. Results: ALDH2 status was related to alcohol response measures for both men and women. ALDH2 status was also related to tension reduction expectancies for women and to expectancies for cognitive behavioral impairment for men. In the male sample, the ALDH2/expectancy relationship was fully explained by the level of response to alcohol. Conclusions: These results represent a first step in understanding the mechanisms by which genetic factors, such as ALDH2 status, can affect alcohol-related learning. [source] Acute, Rapid, and Chronic Tolerance During Ontogeny: Observations When Equating Ethanol Perturbation Across AgeALCOHOLISM, Issue 9 2001Marisa M. Silveri Background: Sensitivity to the motor-impairing and hypnotic effects of ethanol (EtOH) increases notably during development. Less is known, however, about the ontogeny of EtOH tolerance and the ontogenetic relationship among different types of tolerance. Consequently, we compared the ontogenetic development of acute, rapid, and chronic tolerance to EtOH-induced motor impairment and hypothermia in a swim task. Methods: Preweanling, adolescent, and adult female and male Sprague-Dawley rats were given chronic saline (control group), five daily EtOH exposures before EtOH on test day (chronic group), one EtOH exposure before test day (rapid group), or EtOH exposure only on test day (acute groups). Separate groups of animals in the acute groups were tested at 15, 60, or 105 min after injection to estimate acute tolerance development via calculating slopes of the linear regression of impairment relative to brain alcohol levels at each postinjection interval. Initial EtOH perturbation of swim performance was equated across age by varying EtOH dose. Results: Acute tolerance was evident to the motor-impairing effects of EtOH at all ages. When impairment was indexed relative to brain alcohol levels, rapid and chronic tolerance to the motor-impairing effects of EtOH on latency to reach the start was seen across age, although this tolerance tended to be more pronounced in adults. Somewhat different ontogenetic patterns of tolerance development were observed with EtOH-induced hypothermia, a dependent measure for which EtOH perturbation was not equated across age. Conclusions: The degree of initial perturbation by EtOH seems to be an important predictor of tolerance expression during ontogeny. That is, ontogenetic profiles of tolerance development differ significantly when EtOH-induced motor impairment is equated across age rather than dose of EtOH administered . The role of target response measures and context stress should also be considered when exploring ontogenetic expression of EtOH tolerance. [source] Initial testing of cisplatin by the pediatric preclinical testing program,PEDIATRIC BLOOD & CANCER, Issue 5 2008Mimi Tajbakhsh BS Abstract Background Cisplatin is one of the most widely used drugs for the treatment of solid tumors in adults and children. Here, we report the activity of cisplatin against the PPTP panels of childhood cancer xenografts. Procedures Cisplatin was evaluated against 23 cell lines, and 40 xenografts representing brain tumors, neuroblastoma, rhabdoid tumors, sarcoma, Wilms tumor, and acute lymphoblastic leukemia (ALL). The IC50 concentration in vitro was determined for 96 hr exposure. Solid tumors were grown subcutaneously in immune-deficient mice, and tumor dimensions measured weekly. ALL xenografts were inoculated intravenously and the percent human CD45+ cells in the peripheral blood determined weekly. The antitumor activity of cisplatin (7 mg/kg administered intraperitoneally on Days 0 and 21) was evaluated using time to event (EFS T/C), tumor growth delay (tumor volume T/C), and objective response measures. Results The median IC50 concentration in vitro was 0.87 µM (0.24,4.29 µM), and cisplatin exhibited broad range activity. Cisplatin induced significant differences in EFS distributions compared to controls in 20/28 solid tumors and 4/8 ALL models. Objective responses were observed in 7/28 solid tumor models (25%): partial responses in three rhabdomyosarcomas and one Ewing's sarcoma; complete responses in one rhabdoid tumor and the medulloblastoma; and a maintained complete response in one Wilms tumor. No objective responses were observed in the ALL panel. Conclusions Cisplatin exhibits significant antitumor activity against a broad range of solid tumor xenograft models and limited activity against ALL xenografts. This preclinical pattern of activity is generally consistent with cisplatin's clinical activity. Pediatr Blood Cancer 2008;50:992,1000. © 2007 Wiley-Liss, Inc. [source] Associations between the American College of Rheumatology pediatric response measures and the continuous measures of disease activity used in adult rheumatoid arthritis: A secondary analysis of clinical trial data from children with Polyarticular-Course Juvenile Idiopathic ArthritisARTHRITIS & RHEUMATISM, Issue 12 2009Sarah Ringold Objective To measure associations between the American College of Rheumatology (ACR) pediatric criteria for improvement and the continuous measures of disease activity used for rheumatoid arthritis in adult patients with polyarticular-course juvenile idiopathic arthritis (JIA). Methods In this retrospective analysis of 2 etanercept trials, disease activity was calculated at baseline, 3 months, and 6 months using the Disease Activity Score (DAS), the DAS based on 28 joints (DAS28), the Simplified Disease Activity Index (SDAI), and the Clinical Disease Activity Index (CDAI). The ACR pediatric response and the European League Against Rheumatism (EULAR) response were also determined for the 3-month and 6-month evaluations. Data were analyzed in 94 patients with JIA independent of the treatment arm. Correlation coefficients between measures were calculated for each visit. The areas under the receiver operating characteristic curve (AUC of ROC) were calculated to assess the discriminative properties of the scores for the ACR pediatric response measures. Results The mean DAS, DAS28, CDAI score, and SDAI score were 3.7, 4.7, 30.8, and 36.4, respectively, at baseline, corresponding to high levels of disease activity (CDAI/SDAI) or moderate levels of disease activity (DAS/DAS28). At 3 months, the mean scores corresponded to low (DAS/DAS28) or moderate (CDAI/SDAI) disease activity. At 6 months, the mean scores corresponded to low disease activity (DAS/DAS28/CDAI) or moderate disease activity (SDAI). Most children met the criteria for a good or moderate EULAR response at 3 months and 6 months. The correlation between continuous outcome measures and each pediatric core set component was moderate to very good. The AUC of ROC values for each measure were high (range 0.76,0.98). Conclusion Good correlation and discriminative abilities were seen between the DAS, DAS28, CDAI, and SDAI for the ACR pediatric criteria for improvement. These disease activity measures may be useful for research and clinical care in polyarticular-course JIA. [source] The maternal Mediterranean dietary pattern is associated with a reduced risk of spina bifida in the offspringBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 3 2009M Vujkovic Objective, The objective of this study was to test the hypothesis whether a maternal dietary pattern is associated with the risk of spina bifida (SB) in the offspring. Design, Case,control study. Setting, Eight clinic sites in the Netherlands, 1999,2001. Sample, A total of 50 mothers of children with SB and 81 control mothers. Methods, Maternal food intakes were obtained by food frequency questionnaires at the standardised study moment of 14 months after the birth of the index child. Principal component factor analysis (PCA) and reduced rank regression (RRR) were used to identify dietary patterns. Main outcome measures, Maternal biomarkers were used as response measures in the RRR analysis and composed of serum and red blood cell (RBC) folate, serum vitamin B12 and total plasma homocysteine. The strength of the use of the dietary pattern in association with SB risk was estimated by odds ratios and 95% CI with the highest quartiles of the dietary pattern as reference. Results, A predominantly Mediterranean dietary pattern was identified by both PCA and RRR. Those dietary patterns were highly correlated (r = 0.51, P < 0.001) and characterised by joint intakes of fruit, vegetables, vegetable oil, alcohol, fish, legumes and cereals and low intakes of potatoes and sweets. We observed a significantly increased risk of SB offspring in mothers with a weak use of the Mediterranean dietary pattern, OR 2.7 (95% CI 1.2,6.1) and OR 3.5 (95% CI 1.5,7.9). The Mediterranean dietary pattern was correlated with higher levels of serum and RBC folate, serum vitamin B12 and lower plasma homocysteine. Conclusion, The Mediterranean dietary pattern seems to be associated with reduction in the risk of offspring being affected by SB. [source] | |||||||||||||