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1.
Environ Pollut ; 311: 119852, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35940489

RESUMO

Microplastics are emerging contaminants ubiquitously distributed in the environment, with rivers acting as their main mode of transport in surface freshwater systems. However, the relative importance of hydrologic processes and source-related variables for benthic microplastic distribution in river sediments is not well understood. We therefore sampled and characterized microplastics in river sediments across the Meramec River watershed (eastern Missouri, United States) and applied a hydrologic modeling approach to estimate the relative importance of river discharge, river sediment load, land cover, and point source pollution sites to understand how these environmental factors affect microplastic distribution in benthic sediments. We found that the best model for the Meramec River watershed includes both source-related variables (land cover and point sources) but excludes both hydrologic transport-related variables (discharge and sediment load). Prior work has drawn similar and dissimilar conclusions regarding the importance of anthropogenic versus hydrologic variables in microplastic distribution, though we acknowledge that comparisons are limited by methodological differences. Nevertheless, our findings highlight the complexity of microplastic pollution in freshwater systems. While generating a universal predictive model might be challenging to achieve, our study demonstrates the potential of using a modeling approach to determine the controlling factors for benthic microplastic distribution in fluvial systems.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos , Rios , Poluentes Químicos da Água/análise
2.
J Environ Manage ; 277: 111431, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33032001

RESUMO

Transformations of forested areas to agricultural and urban uses are known to degrade freshwater ecosystems, in part, because of increased surface runoff and soil erosion. Changes in climate are expected to exacerbate these impacts, particularly through increases and intensification of precipitation events during various times of the year. While decreases in greenhouse gas emissions are ultimately necessary to minimize changes in climate, best management practices (BMPs), such as reforestation, can serve as watershed climate adaptation strategies to mitigate the impacts of changes in air temperature and precipitation. The Meramec River Basin (MRB) in eastern Missouri is of economic and recreational importance and supports high levels of biodiversity. While much of the MRB is forested, various land transformations are increasing sediment inputs throughout the basin, and these contributions are expected to increase as climate changes. To address the potential of riparian reforestation to serve as a climate adaptation strategy in the MRB, we developed a Soil and Water Assessment Tool model to simulate streamflow and sediment transport throughout the basin. We then used model outputs characterizing spatial variation in sediment yields to identify critical source areas (CSAs) at the subbasin level. The application of a riparian buffer BMP was simulated in each CSA to quantify the effectiveness of this strategy in reducing sediment for contemporary conditions (1990-2009) as well as under three future climate scenarios for two time periods, 2040-2059 (mid-century) and 2080-2099 (late-century). For the contemporary period, the simulated addition of a riparian buffer BMP resulted in a projected 12.1% average reduction in surface sediment yield among CSAs. For the mid-century projection, subbasin surface sediment output is projected to increase by an average of 277.5% and 221.8% for the climate change scenario and the climate change + BMP scenario, respectively. In the late-century, respective increases in sediment for CSAs are estimated to be, on average, 690.7% and 528.3% for the climate change scenario and the climate change + BMP scenario. Results suggest that surface sediment yields will increase with climate change even with riparian buffer BMP applications. While adding a riparian buffer can potentially reduce sediment outputs, the reduction, on average, is likely inadequate to fully offset the impacts from changes in climate.


Assuntos
Ecossistema , Rios , Agricultura , Mudança Climática , Missouri
3.
Front Pediatr ; 8: 557, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33194877

RESUMO

Introduction: To establish a pilot study on applying two low dose (40 h) constraint-induced movement therapy (CIMT) interventions in children with hemiplegic cerebral palsy (CP) after botulinum toxin (BoNT-A) injection during preschool education. Methods: Five children with spastic CP (mean age: 5.31 years; Gross Motor Function Classification System level I and II) undergoing regular BoNT-A injections and rehabilitation programs were included. Participants were randomly allocated to one of two CIMT programs (40 h): a 2-week 4-hours/day CIMT program and a 4-week 2-hours/day CIMT program. One CIMT program was performed 1 month after a BoNT-A injection, and then the second program was implemented with the next injection. The outcomes were measured by changes in Goal Attainment Scaling (GAS), the grasp and Visual-Motor Integration (VMI) test in Peabody-Developmental Motor Scales (PDMS), the self-care scale on the Functional Skill Scale, and the Caregiver Assistance in Chinese Version of Pediatric Evaluation of Disability Inventory (PEDI-C), Anxiety and Oppositional Defiance Problems of Achenbach System of Empirically-Based Assessment before and after the CIMT interventions, and at every 2 months' follow-up thereafter. Results: The mean age of the participants was 5.31 years, BMI was 16.7 (kg/m2), VIQ was 86.4 ± 8.5, and dose of BoNT-A injection in the upper limb was 42 ± 26.6 units. Grasp, VMI, and self-care on the Functional Skill Scale were significantly better in the 4-week 2-hours/day CIMT program (p < 0.001, p = 0.001, p < 0.001). GAS, grasp, VMI, two 2 self-care scales of PEDI were significantly improved after the CIMT programs, and improvement continued for up to 4 months after the programs. There was no clinical evidence showing changes in the scores for anxiety and oppositional defiance problems during the study period. Conclusions: The preliminary findings, although limited, suggest a potential therapeutic role for the school-based CIMT program after BoNT-A injection. The 4-week 2-hours/day CIMT program might be better than a 2-week 4-hours/day program in terms of self-care and hand function when performed in kindergarten in this pilot study. Furthermore, this pilot study provides valuable information; therefore, it is crucial to include more CP children and blinded assessors for hand function and ADL in the future study.

4.
Laryngoscope ; 114(12): 2172-5, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15564839

RESUMO

OBJECTIVE/HYPOTHESIS: It was the authors' premise that the vestibular evoked myogenic potential (VEMP) test may be used to differentiate acute low-tone hearing loss (ALHL) from Meniere's disease with low-tone HL. STUDY DESIGN: Prospective study. METHODS: From January 2000 to December 2002, consecutive 12 patients with ALHL and another 12 patients with definite Meniere's disease with low-tone HL were enrolled in this study. All patients underwent audiometry and VEMP test, before and after treatment with isosorbide for 3 consecutive months. RESULTS: Before treatment, 12 patients with ALHL revealed normal VEMPs (11, 92%) and augmented VEMPs (1). After treatment, 11 (92%) patients had resolved to normal hearing within 3 days. One year later, two (17%) patients progressed to Meniere's disease. In comparison with Meniere's disease, 6 (50%) of 12 patients showed normal VEMPs before treatment, and 7 (58%) patients had their hearing improved 3 months after treatment. Comparison of VEMP responses or hearing outcome between both groups exhibited significant differences. CONCLUSION: Most patients with ALHL reveal normal VEMPs throughout the episode, indicating that the saccule is spared. In contrast, 50% of Meniere's disease patients with low-tone HL demonstrate abnormal VEMPs, showing a significant difference. Therefore, the VEMP test can be used to differentiate ALHL from Meniere's disease with low-tone HL.


Assuntos
Audiometria de Resposta Evocada , Perda Auditiva Neurossensorial/diagnóstico , Isossorbida/uso terapêutico , Adulto , Limiar Auditivo , Estudos de Casos e Controles , Eletromiografia , Potenciais Evocados Auditivos , Feminino , Perda Auditiva Neurossensorial/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Probabilidade , Estudos Prospectivos , Fatores de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Testes de Função Vestibular
5.
Ann Otol Rhinol Laryngol ; 113(2): 113-4, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14994764

RESUMO

A 74-year-old man came to our hospital with complete left vocal cord paralysis and erythema of the prelaryngeal skin. The patient also had mucosal swelling and erosions in the left arytenoid cartilage, aryepiglottic fold, and pyriform sinus. Herpetic vesicles developed over the prelaryngeal erythema 4 days after admission. An increase in the varicella-zoster immunoglobulin G level to 3,294 IU/mL confirmed varicella-zoster virus infection of the larynx and prelaryngeal skin. The patient was treated with acyclovir without marked effect. Nevertheless, in cases of unilateral vocal cord paralysis and erythema of the ipsilateral prelaryngeal skin, we advise that herpes zoster laryngis must be considered and treatment with early intravenous acyclovir started.


Assuntos
Eritema/virologia , Herpes Zoster/diagnóstico , Doenças da Laringe/diagnóstico , Laringite/virologia , Idoso , Humanos , Masculino , Pele/patologia , Paralisia das Pregas Vocais/virologia
6.
Am J Rhinol ; 18(6): 411-4, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15706991

RESUMO

BACKGROUND: The first case report of spontaneous enophthalmos due to maxillary atelectasis as a late complication of FESS is presented. METHODS: Chart review of a 24-year-old male who developed a left progressive enophthalmos within three months post bilateral functional endoscopic sinus surgery. RESULTS: The preoperative computed tomography showed a normal left maxillary sinus. The postoperative computed tomography revealed a left maxillary atelectasis with a descending orbital floor. The subject received revised endoscopic sinus surgery and his enophthalmos was stable without further progression after the operation. CONCLUSIONS: This may have been caused by an ostium occlusion with retention of secretions inducing sinus inflammation, osteolytic activity, and osseous remodeling of the sinus walls. A negative pressure may develop. When the pressure gradient exceeds the sinus wall tension, maxillary atelectasis and enophthalmos occur. Prevention of this complication of FESS should include making a patent naso-antral window, minimizing mucosal trauma, and careful postoperative sinoscopic treatment. A "functional" sinus is the goal.


Assuntos
Endoscopia/efeitos adversos , Enoftalmia/etiologia , Sinusite Maxilar/cirurgia , Adulto , Enoftalmia/diagnóstico por imagem , Enoftalmia/fisiopatologia , Humanos , Masculino , Sinusite Maxilar/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento
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