98 research outputs found
Controls on anthropogenic radionuclide distribution in the Sellafield-impacted Eastern Irish Sea
Understanding anthropogenic radionuclide biogeochemistry and mobility in natural systems is key to improving the management of radioactively contaminated environments and radioactive wastes. Here, we describe the contemporary depth distribution and phase partitioning of 137Cs, Pu, and 241Am in two sediment cores taken from the Irish Sea (Site 1: the Irish Sea Mudpatch; Site 2: the Esk Estuary). Both sites are located ~10 km from the Sellafield nuclear site. Low-level aqueous radioactive waste has been discharged from the Sellafield site into the Irish Sea for >50 y. We compare the depth distribution of the radionuclides at each site to trends in sediment and porewater redox chemistry, using trace element abundance, microbial ecology, and sequential extractions, to better understand the relative importance of sediment biogeochemistry vs. physical controls on radionuclide distribution/post-depositional mobility in the sediments. We highlight that the distribution of 137Cs, Pu, and 241Am at both sites is largely controlled by physical mixing of the sediments, physical transport processes, and sediment accumulation. Interestingly, at the Esk Estuary, microbially-mediated redox processes (considered for Pu) do not appear to offer significant controls on Pu distribution, even over decadal timescales. We also highlight that the Irish Sea Mudpatch likely still acts as a source of historical pollution to other areas in the Irish Sea, despite ever decreasing levels of waste output from the Sellafield site.Peer reviewe
Cognitive Effects of Risperidone in Children with Autism and Irritable Behavior
Objective:
The objective of this research was to explore the effects of risperidone on cognitive processes in
children with autism and irritable behavior.
Method:
Thirty-eight children, ages 5-17 years with autism and severe behavioral disturbance, were
randomly assigned to risperidone (0.5 to 3.5 mg/day) or placebo for 8 weeks. This sample of 38 was a subset
of 101 subjects who participated in the clinical trial; 63 were unable to perform the cognitive tasks. A
double-blind placebo-controlled parallel groups design was used. Dependent measures included tests of
sustained attention, verbal learning, hand-eye coordination, and spatial memory assessed before, during, and
after the 8-week treatment. Changes in performance were compared by repeated measures ANOVA.
Results:
Twenty-nine boys and 9 girls with autism and severe behavioral disturbance and a mental age ≥18
months completed the cognitive part of the study. No decline in performance occurred with risperidone.
Performance on a cancellation task (number of correct detections) and a verbal learning task (word
recognition) was better on risperidone than on placebo (without correction for multiplicity). Equivocal
improvement also occurred on a spatial memory task. There were no significant differences between
treatment conditions on the Purdue Pegboard (hand-eye coordination) task or the Analog Classroom Task
(timed math test).
Conclusion:
Risperidone given to children with autism at doses up to 3.5 mg for up to 8 weeks appears to have no
detrimental effect on cognitive performance
Risperidone Treatment of Autistic Disorder: Longer-Term Benefits and Blinded Discontinuation After 6 Months
Objective: Risperidone is effective for short-term treatment of aggression, temper outbursts, and self-injurious behavior in children with autism. Because these behaviors may be chronic, there is a need to establish the efficacy and safety of longer-term treatment with this agent.
Method: The authors conducted a multisite, two-part study of risperidone in children ages 5 to 17 years with autism accompanied by severe tantrums, aggression, and/or self-injurious behavior who showed a positive response in an earlier 8-week trial. Part I consisted of 4-month open-label treatment with risperidone, starting at the established optimal dose; part II was an 8-week randomized, double-blind, placebo-substitution study of risperidone withdrawal. Primary outcome measures were the Aberrant Behavior Checklist irritability subscale and the Clinical Global Impression improvement scale.
Results: Part I included 63 children. The mean risperidone dose was 1.96 mg/day at entry and remained stable over 16 weeks of open treatment. The change on the Aberrant Behavior Checklist irritability subscale was small and clinically insignificant. Reasons for discontinuation of part I included loss of efficacy (N=5) and adverse effects (N=1). The subjects gained an average of 5.1 kg. Part II included 32 patients. The relapse rates were 62.5% for gradual placebo substitution and 12.5% for continued
risperidone; this difference was statistically significant.
Conclusions: Risperidone showed persistent efficacy and good tolerability for intermediate-length treatment of children with autism characterized by tantrums, aggression, and/or self-injurious behavior. Discontinuation after 6 months was associated with a rapid return of disruptive and aggressive behavior in most subjects
Expanding Social Science Through Disaster Studies
Objectives. This article provides an overview of how the interdisciplinary field of disaster studies contributes to the social sciences.
Methods. The following themes are explored in relation to the articles contained in the special issue: disasters are social and political phenomena that generate policy change, disasters reflect and affect democratic governance, and disasters reveal shared experience and collective identity.
Results. Disaster studies bridge the social sciences theoretically and methodologically. Given the scope of disaster impacts—across social, political, economic, ecological, and infrastructure spheres—and the policy response they garner involving public, private, and civic actors, they offer a lens by which to see society and politics in a way that no other critical events can.
Conclusion. Disaster studies offer important applications of social science theories and concepts that expand the field, broaden our reach as social scientists, and deepen our understanding of fundamental social processes and behaviors in meaningful ways
Measuring Patient and Clinician Perspectives to Evaluate Change in Health-Related Quality of Life Among Patients with Chronic Obstructive Pulmonary Disease
CONTEXT: Many treatments aim to improve patients’ health-related quality of life (HRQoL), and many care guidelines suggest assessing symptoms and their impact on HRQoL. However, there is a lack of consensus regarding which HRQoL outcome measures are appropriate to assess, and how much change on those measures depict significant HRQoL improvement. OBJECTIVE: We used triangulation methods to identify and understand clinically important differences (CIDs) for the amount of change in HRQoL that reflects both health professionals and patients’ values, among patients with chronic obstructive pulmonary disease (COPD). DESIGN, SETTING, AND PARTICIPANTS: We incorporated three perspectives: (1) an expert panel of physicians familiar with the measurement of HRQoL in COPD patients; (2) 610 primary care COPD outpatients who completed baseline and bimonthly follow-up HRQoL interviews over the 12-month study; and (3) the primary care physicians (PCPs; n = 43) of these outpatients who assessed their patients’ disease at baseline and at subsequent PCP visits during the year long study. MEASUREMENTS: The Chronic Respiratory Disease Questionnaire (CRQ), the Medical Outcomes Study Short Form 36-item survey (SF-36, version 2.0), and global assessments of change from each of the three perspectives for all HRQoL domains. RESULTS: With few exceptions, the CRQ was able to detect small changes at levels reported by the patients (1–2 points) and their PCPs (1–5 points). These results confirm minimal important difference standards developed in 1989 by Jaeschke et al. anchored on patient-perceived changes in HRQoL. In general, the expert panel and PCP CIDs were larger than the patient CIDs. CONCLUSION: This triangulation methodology yielded improved interpretation, understanding, and insights on stakeholder perspectives of CIDs for patient-reported outcomes
Rebounding from disruptive events: Business recovery following the Northridge earthquake
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