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The design of footbridges has begun to receive more attention in recent years due to cases in which undesirable vibrations occurred. The utilization of passive energy dissipation systems to control bridge responses has become popular as a remedy for this matter. This paper proposes the use of inerters to mitigate pedestrian bridge vibrations, and explores their potential. This is done by presenting a topology and sizing optimization methodology for pedestrian bridges equipped with fluid viscous dampers and inerters. Planar truss-like bridges are examined, loaded under dynamic and static loads. All constructive elements' sizes (including dampers) serve as continuous design variables. The objective is to minimize a cost function of the bridge. The optimization process is constrained by demanding responses of interest not to exceed allowable values, along with global and local buckling. A first-order gradient-based optimization algorithm is adopted to lessen the computational effort. Lastly, a discretization postprocess is offered to lead to discrete designs of relevant design variables, such as steel cross sections. The results shed light on the advantages of combining inerters in pedestrian bridges. [ABSTRACT FROM AUTHOR]

Previous research has shown that weakening of inelastic structures can limit the maximum response accelerations they experience during ground motions, but may lead to an increase in the displacements (or interstory drifts). Added damping by using fluid viscous devices, on the other hand, reduces the interstory drifts and has no significant effect on total accelerations, when structures behave inelastically. The weakening and damping technique, thus, limits the total acceleration due to the weakening, and reduces the interstory drifts by adding damping, and hence addresses the two main causes for both structural and nonstructural damage in buildings. Optimal weakening and damping, which is the subject of this paper, involves the determination of the optimal locations and amount of weakening of the structural components as well as the optimal locations and magnitudes of added dampers. Weakening of the structure might create stability issues in the building that can be automatically considered, if active control theory is used for design. Based on a nonlinear active control procedure, control forces are calculated and implemented using equivalent passive dampers and weakening elements in order to achieve the closest effects. The methodology is applied to a case study of an eight-story nonlinear building tested using a set of ground motions corresponding to different hazard levels. Results show that the optimal design leads to a reduction of both peak interstory drifts and peak total accelerations. DOI: 10.1061/(ASCE)0733-9445(2008)134:10(1638) CE Database subject headings: Optimization; Seismic effects; Damping; Inelasticity; Ground motion.

Background and Hypotheses: In the past 2 decades, substantial effort has been put into research on therapeutic options for people at ultra-high risk (UHR) for developing a first episode of psychosis (FEP), focusing on omega-3 polyunsaturated fatty acids (PUFAs) in preventing transition to psychosis. Despite an initial positive finding, subsequent studies failed to find a beneficial effect. The current study aimed to further investigate the effect of omega-3 PUFAs in UHR, to determine whether this line of research is worth pursuing., Study Design: A double-blind, randomized, placebo-controlled study testing the efficacy of 6-month treatment with omega-3 PUFAs in 135 subjects at UHR for FEP, aged 13 to 20 years on the prevention of a transition to psychosis, followed up for 18 months post-treatment. The trial was conducted at 16 general hospitals and psychiatric specialty centers located in 8 European countries and Israel., Study Results: There was no beneficial effect of treatment with omega-3 PUFAs compared to placebo; the rate of transition over 2 years did not differ between treatment arms nor was there a difference in change in symptom severity after 6-month treatment. Dropout rates and serious adverse events were similar across the groups., Conclusions: This is the third study that fails to replicate the original finding on the protective effect of omega-3 PUFAs in UHR subjects for transition to psychosis. The accumulating evidence therefore suggests that omega-3 PUFAs do not reduce transition rates to psychosis in those at increased risk at 2 years follow-up., Clinical Trials: This trial is registered with ClinicalTrials.gov (NCT02597439; Study Details | Placebo-controlled Trial in Subjects at Ultra-high Risk for Psychosis With Omega-3 Fatty Acids in Europe | ClinicalTrials.gov)., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center.)

Background: Adolescent obesity has markedly increased worldwide, and metabolic bariatric surgery is an effective treatment option. A major predictor of the outcomes of this procedure is adherence to post-surgery lifestyle changes and medical recommendations. While adolescents generally have more difficulty adhering to medical advice than adults, their failure to do so could adversely affect their physical and psychological health, the cost-effectiveness of medical care, and the results of clinical trials. To our knowledge, this is the first attempt to identify the characteristics associated with the adherence of adolescents and their families to medical advice after bariatric surgery. Methods: We investigated potential variables influencing adherence to medical advice in adolescents diagnosed with severe obesity enrolled in a nutritional and behavior-oriented bariatric program-a 3-month pre-surgical outpatient intervention and a 6-month post-surgical follow-up. The program monitored weight, program attendance, diet compliance, lifestyle changes, and daily activities. All participants and parents completed a standard battery of questionnaires, provided demographic information, and participated in a semi-structured interview about their lifestyle. Results: The study group consisted of 47 adolescents: 34 girls and 13 boys, aged 13-18 years. Over time, three groups emerged with different degrees of adherence-high, low, and delayed low adherence. The analyses showed that adolescents' depression, autonomy, and independence from their family had strong, significant effects on adherence across the groups. Conclusions: Using adherence typologies, practitioners may be able to identify, predict, and tailor interventions to improve adolescent adherence to post-surgery recommendations. Parents have an important role in ensuring that adolescents undergoing metabolic bariatric surgery follow medical advice after the procedure.

Objectives: The aim of this study was to characterize the clinical profiles, tolerability, and efficacy of two groups of antidepressants, selective serotonin reuptake inhibitors (SSRIs), and the atypical antidepressant, mirtazapine, in children and adolescents treated in a large pediatric Hematology-Oncology center. Methods: A review of computerized medical charts of 32 pediatric patients with cancer, from December 2011 to April 2020, was conducted. Efficacy and tolerability of antidepressant medications were retrospectively analyzed. The Clinical Global Impressions-Severity (CGI-S) and Clinical Global Impressions-Improvement (CGI-I) Scales were used to evaluate psychiatric symptoms severity before and following treatment, while the data on adverse events and drug-drug interactions were retrieved from the computerized medical records. Results: Thirty-two children and adolescents with cancer, 2-21 years of age (mean 14.1 ± 4.6 years), were treated with antidepressants. Fourteen patients (44%) received mirtazapine, whereas 18 patients (56%) received SSRIs: sertraline (25%), escitalopram (25%), or fluoxetine (6%). Treatment choice was dictated either by physician preference or informed by potential drug-drug interactions. The most common psychiatric diagnoses were major depressive disorders (47%), anxiety disorders (19%), and medication-induced psychiatric disorders (19%). The most common psychiatric-medical symptoms were depressed mood (94%) and anxiety (62%). CGI-S improved significantly ( p  < 0.05) between pretreatment and on-treatment assessments, with no statistically significant difference between SSRI and mirtazapine-treated patients. CGI-I scores at reassessment indicated improvement in most patients (84%). Adverse events of treatment were mild in all patients. Conclusions: The antidepressants used in this study, SSRIs and mirtazapine, were effective and well tolerated in children and adolescents with cancer and psychiatric comorbidities. Given the high rates of depression and anxiety in children with cancer, large-scale, multisite, prospective clinical trials of antidepressants are warranted.

Introduction: Psychotic disorders are associated with a severe functional decline and a significant impact on the quality of life. These disorders usually develop gradually, lasting days to months-years. The early phase of psychotic disorders is termed "pre-psychotic" or "prodromal". It is estimated that 30% of the individuals presenting with prodromal symptoms will develop psychosis in three years. This high-risk state is also known as "clinical high risk" (CHR), "ultra-high risk" (UHR), and "at-risk mental state" (ARMS). The diagnostic criteria of high-risk subjects include 3 groups: 1) genetic risk with a functional decline; 2) brief limited intermittent psychotic symptoms group (BLIPS); 3) subthreshold positive psychotic symptoms. In addition to the psychosis risk, these subjects suffer from distress, functional deterioration and psychiatric comorbidities that influence their quality of life. Therefore, many efforts are invested in early identification of the high-risk for psychosis subjects with the primary aim of using interventions to delay or prevent conversion to psychosis. Studies in the field have highlighted specific factors that predict the risk to develop psychosis and even developed predictive models. Interventions including cognitive-behavioral therapy, integrative psychological therapy and pharmacological therapy were found to be associated with postponing the conversion to psychosis. According to current guidelines, cognitive behavioral therapy is the first-choice intervention, and pharmacological interventions should be reserved for patients with comorbidities in need of stabilization of severe and progressive symptoms. Further prospective studies will allow a better identification of high-risk patients and enable the development of interventions for prevention and treatment of this population.

Objectives: The present study characterized the psychiatric diagnoses and symptoms that led to the administration of antipsychotic medications in children and adolescents with cancer, and to evaluate the benefits and tolerability of these drugs in a large hospital-based pediatric hematology-oncology practice. Methods: Efficacy and adverse effects of two second-generation antipsychotics were retrospectively analyzed in 43 patients 2.9-19.6 (mean 12.1) years of age. The Clinical Global Impression-Severity (CGI-S) Scale and Improvement (CGI-I) Scale were used to evaluate psychiatric symptom severity before and following treatment, while the incidence of side effects and drug-drug interactions were collected from medical records. Results: Olanzapine was administered to 58% of patients and risperidone to 42%; the choice of drug was at the discretion of the treating psychiatrist. The common psychiatric diagnoses among these patients included adjustment disorder (37%) and medication-induced psychiatric disorders (23%). The most common psychiatric-medical symptoms included irritability/agitation (79%) and depressed mood (74%). CGI-S improved significantly ( p  < 0.001) between assessments, with no statistically significant difference between olanzapine- and risperidone-treated patients. CGI-I scores at reassessment indicated superiority of olanzapine as compared with risperidone. Adverse effects of treatment were mild. Conclusions: Olanzapine and risperidone can be well tolerated and ameliorate severe psychiatric-medical symptoms in children and adolescents with cancer. The potential palliative benefits of these second-generation antipsychotics (e.g., rapid onset of action, antiemesis, sedation, and appetite stimulation) increase the utility of their use in children treated in oncology and bone marrow transplant units.

Background: Venous thromboembolism (VTE) is a frequent complication of patients who experienced major trauma. Prevention of VTE is usually by thrombophylaxis and or by the use of a retrievable filter. Lately, the use of a retrievable filter in trauma patients has increased despite evidence cautioning against its use., Aims: To evaluate complications related to a single type of filter prophylactically used in a tertiary trauma center and search for risk factors that may preclude filter retrieval, Methods: 142 patients aged 16 through 60 who experienced a major trauma and were treated with a prophylactic IVC filter of type optease were evaluated., Results: The median time from trauma to filter insertion was 2days and low molecular weight heparin at prophylactic dose was initiated in 92% once the filter was inserted. Nine patients developed IVC thrombosis and one of them died despite the use of thrombolytic therapy. Another 8 patients developed lower extremities deep vein thrombosis. The filter was left in place in 13 more patients after attempted filter removal was unsuccessful. Among patients with successful removal, the median dwelling time was 30days. There was no relationship between successful removal and age, sex, BMI, Glasgow coma scale, or injury severity score of patients when first evaluated., Conclusions: Of concern is the persistent complications related to IVC filter even with the prophylactic use of anticoagulants and the dose of radiation trauma patients were exposed during insertion and retrieval of filter. Thus, the routine use of IVC filter in trauma patients may not be desirable., (Copyright © 2015 Elsevier Ltd. All rights reserved.)