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In this work, germanium nanowires rendered fully amorphous via xenon ion irradiation have been annealed within a transmission electron microscope to induce crystallization. During annealing crystallites appeared in some nanowires whilst others remained fully amorphous. Remarkably, even when nucleation occurred, large sections of the nanowires remained amorphous even though the few crystallites embedded in the amorphous phase were formed at a minimum of 200 °C above the temperature for epitaxial growth and 100 °C above the temperature for random nucleation and growth in bulk germanium. Furthermore, the presence of crystallites was observed to depend on the diameter of the nanowire. Indeed, the formation of crystallites occurred at a higher annealing temperature in thin nanowires compared with thicker ones. Additionally, nanowires with a diameter above 55 nm were made entirely crystalline when the annealing was performed at the temperature normally required for crystallization in germanium (i.e. 500 °C). It is proposed that oxygen atoms hinder both the formation and the growth of crystallites. Furthermore, as crystallites must reach a minimum size to survive and grow within the amorphous nanowires, the instability of crystallites may also play a limited role for the thinnest nanowires.
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Doenças Musculoesqueléticas , Gestantes , Gravidez , Feminino , Humanos , Doenças Musculoesqueléticas/terapiaRESUMO
BACKGROUND: Natalizumab (NTZ), a monoclonal antibody to human α4ß1/ß7 integrin, is an effective therapy for multiple sclerosis (MS), albeit associated with progressive multifocal leukoencephalopathy (PML). Clinicians have been extending the dose of infusions with a hypothesis of reducing PML risk. The aim of the study is to evaluate the clinical consequences of reducing NTZ frequency of infusion up to 8â weeks 5â days. METHODS: A retrospective chart review in 9 MS centres was performed in order to identify patients treated with extended interval dosing (EID) regimens of NTZ. Patients were stratified into 3 groups based on EID NTZ treatment schedule in individual centres: early extended dosing (EED; n=249) every 4â weeks 3â days to 6â weeks 6â days; late extended dosing (LED; n=274) every 7â weeks to 8â weeks 5â days; variable extended dosing (n=382) alternating between EED and LED. These groups were compared with patients on standard interval dosing (SID; n=1093) every 4â weeks. RESULTS: 17% of patients on SID had new T2 lesions compared with 14% in EID (p=0.02); 7% of patients had enhancing T1 lesions in SID compared with 9% in EID (p=0.08); annualised relapse rate was 0.14 in the SID group, and 0.09 in the EID group. No evidence of clinical or radiographic disease activity was observed in 62% of SID and 61% of EID patients (p=0.83). No cases of PML were observed in EID group compared with 4 cases in SID cohort. CONCLUSIONS: Dosing intervals up to 8â weeks 5â days did not diminish effectiveness of NTZ therapy. Further monitoring is ongoing to evaluate if the risk of PML is reduced in patients on EID.
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Leucoencefalopatia Multifocal Progressiva/induzido quimicamente , Leucoencefalopatia Multifocal Progressiva/prevenção & controle , Esclerose Múltipla/tratamento farmacológico , Natalizumab/administração & dosagem , Natalizumab/uso terapêutico , Adulto , Esquema de Medicação , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Natalizumab/efeitos adversos , Neuroimagem , Recidiva , Estudos RetrospectivosRESUMO
Fasciolosis, a food-borne trematodiasis, results following infection with the parasites, Fasciola hepatica and Fasciola gigantica. These trematodes greatly affect the global agricultural community, infecting millions of ruminants worldwide and causing annual economic losses in excess of US $3 billion. Fasciolosis, an important zoonosis, is classified by WHO as a neglected tropical disease with an estimated 17 million people infected and a further 180 million people at risk of infection. The significant impact on agriculture and human health together with the increasing demand for animal-derived food products to support global population growth demonstrate that fasciolosis is a major One Health problem. This review details the problematic issues surrounding fasciolosis control, including drug resistance, lack of diagnosis and the threat that hybridization of the Fasciola species poses to future animal and human health. We discuss how these parasites may mediate their long-term survival through regulation and modulation of the host immune system, by altering the host immune homeostasis and/or by influencing the intestinal microbiome particularly in respect to concurrent infections with other pathogens. Large genome, transcriptome and proteomic data sets are now available to support an integrated One Health approach to develop novel diagnostic and control strategies for both animal and human disease.
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Fasciolíase/prevenção & controle , Animais , Fasciola , Fasciola hepatica , Humanos , Proteômica , ZoonosesRESUMO
AIM: To evaluate the effect on recurrent admission for alcohol-induced pancreatitis (that can be up to 48%) of a brief social work intervention for alcohol dependence in a single center in Ireland METHODS: Retrospective cohort study of patients admitted with acute alcohol-induced pancreatitis to a tertiary hospital in Ireland from January 2009 to December 2012. RESULTS: The relapse rate in the cohort of 160 patients with alcohol-induced pancreatitis was 28.1%. There was no difference in the relapse rate of those patients who received a social work intervention compared with those who did not (ANOVA, P = 0.229). The employment status was a significant risk factor for relapse (ANOVA, P = 0.027), but did not differ between those who did, and did not, receive the intervention. CONCLUSION: Although the cohort size did not allow great statistical power, it appears that our hospital's current social work intervention for alcohol-induced pancreatitis is ineffective in preventing relapse. Long-term prospective studies are required to formulate and better implement more efficacious interventions for such patients.
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Pancreatite Alcoólica/prevenção & controle , Serviço Social , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Irlanda , Masculino , Pessoa de Meia-Idade , Pancreatite Alcoólica/terapia , Recidiva , Estudos Retrospectivos , Fatores de Risco , Adulto JovemRESUMO
The M2 subset of macrophages has a critical role to play in host tissue repair, tissue fibrosis and modulation of adaptive immunity during helminth infection. Infection with the helminth, Fasciola hepatica, is associated with M2 macrophages in its mammalian host, and this response is mimicked by its excretory-secretory products (FhES). The tegumental coat of F. hepatica (FhTeg) is another major source of immune-modulatory molecules; we have previously shown that FhTeg can modulate the activity of both dendritic cells and mast cells inhibiting their ability to prime a Th1 immune response. Here, we report that FhTeg does not induce Th2 immune responses but can induce M2-like phenotype in vivo that modulates cytokine production from CD4(+) cells in response to anti-CD3 stimulation. FhTeg induces a RELMα expressing macrophage population in vitro, while in vivo, the expression of Arg1 and Ym-1/2 but not RELMα in FhTeg-stimulated macrophages was STAT6 dependent. To support this finding, FhTeg induces RELMα expression in vivo prior to the induction of IL-13. FhTeg can induce IL-13-producing peritoneal macrophages following intraperitoneal injection This study highlights the important role of FhTeg as an immune-modulatory source during F. hepatica infection and sheds further light on helminth-macrophage interactions.
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Antígenos de Helmintos/imunologia , Fasciola hepatica/fisiologia , Fasciolíase/imunologia , Macrófagos/imunologia , Animais , Células Dendríticas/imunologia , Fasciolíase/parasitologia , Interleucina-13/imunologia , Macrófagos Peritoneais/imunologia , Mastócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fator de Transcrição STAT6/metabolismoRESUMO
Sputtering yields, enhanced by more than an order of magnitude, have been observed for 80 keV Xe ion irradiation of monocrystalline Au nanorods. Yields are in the range 100-1900 atoms/ion compared with values for a flat surface of ≈50. This enhancement results in part from the proximity of collision cascades and ensuing thermal spikes to the nanorod surfaces. Molecular dynamic modeling reveals that the range of incident angles occurring for irradiation of nanorods and the larger number of atoms in "explosively ejected" atomic clusters make a significant contribution to the enhanced yield.
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The prevalence and duration of the long-term respiratory complications of COVID-19 infection remains to be elucidated. This short commentary reports on recently published studies in patients post-acute COVID-19 infection in terms of symptom prevalence, physiological and radiological sequela and where only symptoms are present despite investigation. Pulmonary function testing, 6-min walk tests, computed tomography chest and more advanced imaging modalities have been incorporated to reveal the underlying pathophysiology that cause such disabling symptoms in patient with post-acute COVID-9 syndrome (PACS). PACS has a serious impact on people's ability to return to work, affecting the physical, mental, social sphere and with significant healthcare and general economic consequences for them, their families and society.
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COVID-19 , COVID-19/complicações , Humanos , Pulmão/diagnóstico por imagem , Testes de Função Respiratória , SARS-CoV-2 , Síndrome de COVID-19 Pós-AgudaRESUMO
Background: As a type of welfare technology, care robotics is now widely seen as a potential aide to rehabilitation, increasing independence and enhancing the wellbeing of people with disabilities and older adults. Research into and development of care robots have both been vigorously promoted in North America, Europe and Asia, and the competition for technological advancement in robotics is becoming fierce. AI ethics and policy guidelines are being established. However, there are still differences in attitudes and perceptions, as well as national policies regarding this type of welfare technology. Moreover, despite the anticipated usefulness, it is believed that progress has been slow in the diffusion of care robots. Purpose: In order to explore how public discourses support technological innovation, such as care robots, while preparing society for potential risks and impact, we sought to ascertain whether public discourse on care robots varies from region to region. For example, what are the hopes and promises associated with care robots and what are the concerns? Methods: To address these questions, this article explored how care robots have been portrayed in five major broadsheet newspapers in five jurisdictions in Asia and Europe (France, Great Britain, Hong Kong SAR, Ireland and Japan). We obtained 545 articles for the period between January 2001 and September 2020, more than half of which originated in Japan. A thematic analysis was conducted of these articles written in four languages (Chinese, English, French and Japanese). Results: Positive and negative narratives were teased out, alongside other key prominent themes identified, such as Japan as the land of robots, the pandemic, and the impact of robots on the economy. As the number of robot-related articles grew from the year 2012 onwards, narratives became more nuanced in European newspapers, but not in Asian ones. Furthermore, recent articles began to address the social and relational impact of care robots, while providing concrete examples of improvements in the quality of life for users. Further careful examination will be necessary in the future in order to establish the impact of robotics use in rehabilitation for people with disabilities, older adults, their carers and society at large.
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Migration inhibitory factor (MIF) is known to exert significant pro-inflammatory effects and has the potential to override the anti-inflammatory action of glucocorticoids. In this study we have identified significant quantities of MIF in the alveolar airspaces of patients with acute respiratory distress syndrome (ARDS). We show in alveolar cells from patients with ARDS that MIF augments pro-inflammatory cytokine secretion (TNF alpha and IL-8), anti-MIF significantly attenuates TNF alpha and IL-8 secretion and MIF overrides, in a concentration-related fashion, the anti-inflammatory effects of glucocorticoids. These findings suggest that MIF may act as a mediator sustaining the pulmonary inflammatory response in ARDS and that an anti-MIF strategy may represent a novel therapeutic approach in inflammatory diseases such as ARDS.
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Fatores Inibidores da Migração de Macrófagos/análise , Síndrome do Desconforto Respiratório do Recém-Nascido/metabolismo , Células Cultivadas , Humanos , Imuno-Histoquímica , Recém-Nascido , Interleucina-8/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Fatores Inibidores da Migração de Macrófagos/fisiologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Resistance to chemotherapy is a principal problem in the treatment of small cell lung cancer (SCLC). We show here that SCLC is surrounded by an extensive stroma of extracellular matrix (ECM) at both primary and metastatic sites. Adhesion of SCLC cells to ECM enhances tumorigenicity and confers resistance to chemotherapeutic agents as a result of beta1 integrin-stimulated tyrosine kinase activation suppressing chemotherapy-induced apoptosis. SCLC may create a specialized microenvironment, and the survival of cells bound to ECM could explain the partial responses and local recurrence of SCLC often seen clinically after chemotherapy. Strategies based on blocking beta1 integrin-mediated survival signals may represent a new therapeutic approach to improve the response to chemotherapy in SCLC.
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Apoptose/fisiologia , Carcinoma de Células Pequenas/metabolismo , Carcinoma de Células Pequenas/patologia , Proteínas da Matriz Extracelular/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Clorometilcetonas de Aminoácidos/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Bradicinina/farmacologia , Carcinoma de Células Pequenas/tratamento farmacológico , Caspase 3 , Inibidores de Caspase , Caspases/metabolismo , Adesão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Colágeno/metabolismo , Ciclofosfamida/farmacologia , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Inibidores Enzimáticos/farmacologia , Etoposídeo/farmacologia , Fibronectinas/metabolismo , Galanina/farmacologia , Humanos , Integrina beta1/metabolismo , Laminina/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Tenascina/metabolismo , Células Tumorais Cultivadas , Tirfostinas/farmacologiaRESUMO
Idiopathic pulmonary fibrosis (IPF) is a progressive fatal disease affecting over 100 000 people in Europe with an increasing incidence. Available treatments offer only slowing of disease progression and are poorly tolerated by patients leading to cessation of therapy. Lung transplant remains the only cure. Therefore, alternative treatments are urgently required. The pathology of IPF is complex and poorly understood and thus creates a major obstacle to the discovery of novel treatments. Additionally, preclinical assessment of new treatments currently relies upon animal models where disparities with human lung biology often hamper drug development. At a cellular level, IPF is characterized by persistent and abnormal deposition of extracellular matrix by fibroblasts and alveolar epithelial cell injury which is seen as a key event in initiation of disease progression. In-depth investigation of the role of alveolar epithelial cells in health and disease has been impeded due to difficulties in primary cell isolation and culture ex vivo. Novel strategies employing patient-derived induced pluripotent stem cells engineered to produce type 2 alveolar epithelial cells (iAEC2) cultured as three-dimensional organoids have the potential to overcome these hurdles and inform new effective precision treatments for IPF leading to improved survival and quality of life for patients worldwide.
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Organoides , Animais , Europa (Continente) , Fibroblastos , Humanos , Fibrose Pulmonar Idiopática , Pulmão , Qualidade de VidaRESUMO
BACKGROUND: The direct effect of the coronavirus disease 2019 (COVID-19) pandemic on patients with intestinal failure (IF) has not been described. METHODS: We conducted a nationwide study of UK IF centers to evaluate the infection rates, presentations, and outcomes in patients with types 2 and 3 IF. RESULTS: A total of 45 patients with IF contracted COVID-19 between March and August 2020; this included 26 of 2191 (1.2%) home parenteral nutrition (HPN)-dependent adults and 19 of 298 (6.4%) adults hospitalized with type 2 IF. The proportion of patients receiving nursing care for HPN administration was higher in those with community-acquired COVID-19 (66.7%) than the proportion in the entire HPN cohort (26.1%; P < .01). Two HPN-dependent and 1 hospitalized patient with type 2 IF died as a direct consequence of the virus (6.7% of 45 patients with types 2 or 3 infected). CONCLUSION: This is the first study to describe the outcomes of COVID-19 in a large cohort of patients requiring long-term PN. Methods to reduce hospital and community nosocomial spread would likely be beneficial.
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COVID-19 , Enteropatias , Nutrição Parenteral no Domicílio , Adulto , Humanos , Enteropatias/complicações , Enteropatias/terapia , Nutrição Parenteral no Domicílio/efeitos adversos , Estudos Retrospectivos , SARS-CoV-2 , Reino Unido/epidemiologiaRESUMO
AIMS/HYPOTHESIS: We examined whether retinal vessel diameter in persons with type 1 diabetes mellitus is associated with changes in subclinical anatomical and functional indicators of diabetic nephropathy. METHODS: Persons with type 1 diabetes mellitus had gradable fundus photographs and renal biopsy data at baseline and 5-year follow-up (n = 234). Retinal arteriolar and venular diameters were measured at baseline and follow-up. Central retinal arteriole equivalent (CRAE) and central retinal venule equivalent (CRVE) were computed. Baseline and 5-year follow-up renal structural variables were assessed by masked electron microscopic morphometric analyses from percutaneous renal biopsy specimens. Variables assessed included: mesangial fractional volume, glomerular basement membrane width, mesangial matrix fractional volume and glomerular basement membrane width composite glomerulopathy index. RESULTS: While controlling for other covariates, baseline CRAE was positively associated with change in the glomerulopathy index over the 5-year period. Change in CRAE was inversely related to a change in mesangial matrix fractional volume and abnormal mesangial matrix fractional volume, while change in CRVE was directly related to change in the volume fraction of cortex that was interstitium [Vv((Int/cortex))] over the 5-year period. Baseline CRAE or CRVE or changes in these diameters were not related to changes in other anatomical or functional renal endpoints. CONCLUSIONS/INTERPRETATION: Independently of other factors, baseline CRAE correlated with changes in glomerulopathy index, a composite measure of extracellular matrix accumulation in the mesangium and glomerular basement membrane. A narrowing of the CRAE was related to mesangial matrix accumulation. Changes in CRVE were related to changes in Vv((Int/cortex),) a measure of interstitial expansion in persons with type 1 diabetes mellitus.
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Diabetes Mellitus Tipo 1/patologia , Nefropatias Diabéticas/patologia , Vasos Retinianos/patologia , Adolescente , Adulto , Análise de Variância , Diabetes Mellitus Tipo 1/fisiopatologia , Nefropatias Diabéticas/fisiopatologia , Método Duplo-Cego , Feminino , Humanos , Rim/patologia , Rim/fisiopatologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Vasos Retinianos/fisiopatologiaRESUMO
Peroxiredoxins (Prx) are a family of anti-oxidants that protect cells from metabolically produced reactive oxygen species (ROS). The presence of these enzymes in the secretomes of many parasitic helminths suggests they provide protection against ROS released by host immune effector cells. However, we recently reported that helminth-secreted Prx also contribute to the development of Th2-responses via a mechanism involving the induction of alternatively activated macrophages. In this review, we discuss the role helminth Prx may play in modulating the immune responses of their hosts.
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Proteínas de Helminto/imunologia , Peroxirredoxinas/imunologia , AnimaisRESUMO
UNLABELLED: Human serum paraoxonase (PON1) activity is reduced in standard hemodialysis (SHD) (4 hours, 3 days/week) patients. Home nocturnal hemodialysis (HNHD) (8 hours, 6 days/week), provides a greater dialysis dose resulting in a greater clearance of metabolites. Whether improvements in the metabolic milieu of HNHD patients results in different PON1 activity levels compared to SHD patients is unclear. We determined serum PON1 mass and arylesterase activities in a group of HNHD patients and compared them to SHD patients and a group of healthy controls (HC). PATIENTS AND METHODS: We measured PON1 arylesterase activity and mass, C-reactive protein (CRP), cystatin C, total and high-density lipoprotein (HDL) cholesterol, triglycerides, apolipoproteins A-I and B in 15 HNHD, 15 SHD and 15 HC participants. RESULTS: PON1 arylesterase activity (p < 0.001) and mass (p < 0.05) were significantly higher in HC participants compared to SHD and HNHD participants, although no significant differences were noted between HD groups. CRP (p < 0.05) was significantly higher in SHD compared to HC participants and there were no significant differences noted between HD groups. Cystatin C (p < 0.001) was significantly different among the 3 groups. There were no significant differences noted in any lipoprotein parameters among the groups. PON1 activity (r = -0.636, p < 0.001) and mass (r = -0.425, p = 0.019) were inversely correlated with CRP in HD patients. CONCLUSION: PON1 is reduced in HNHD patients compared to HC subjects, independent of the concentration of HDL cholesterol. Within subjects on HD, the combination of increased CRP and reduced PON1 may identify subjects at a high risk for cardiovascular complications.
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Arildialquilfosfatase/sangue , Proteína C-Reativa/metabolismo , Falência Renal Crônica/enzimologia , Diálise Renal/métodos , Adulto , Biomarcadores/sangue , Doenças Cardiovasculares/enzimologia , Doenças Cardiovasculares/etiologia , Feminino , Seguimentos , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Fatores de TempoRESUMO
BACKGROUND & AIMS: Genetic Haemochromatosis (GH) is common in North European and Celtic populations and is associated with arthropathy. We aimed to measure the frequency of the common GH mutations (C282Y and H63D), the carrier frequency of C282Y and markers of iron overload in patients who were referred to our rheumatology and joint replacement clinics. METHODS: Unselected patients attending these clinics were anonymously tested for the described mutations. Transferrin saturation and serum ferritin were also measured and if elevated, the patients had predictive counselling then named GH mutation testing. The carrier and mutation frequencies were also determined in 340 local controls. RESULTS: One hundred and sixty-one unselected patients attending these clinics were studied. The C282Y mutation carrier frequency was 1 in 5.2 in patients compared with 1 in 8.1 in controls (p < 0.005). The overall mutation frequencies were similar in patients and controls. One patient was found to be a homozygous for the C282Y mutation and eight were compound heterozygotes. Seven other patients had a raised ferritin, one of whom was a C282Y heterozygote. CONCLUSION: The C282Y carrier frequency is significantly higher in patients attending rheumatology and joint replacement clinics than in controls. Screening of these patients for GH should be considered.
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Artroplastia de Substituição , Hemocromatose/epidemiologia , Artropatias/genética , Doenças Reumáticas/genética , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Hemocromatose/genética , Hemocromatose/cirurgia , Proteína da Hemocromatose , Heterozigoto , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Artropatias/metabolismo , Artropatias/cirurgia , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Mutação/genética , Prevalência , Doenças Reumáticas/metabolismo , Doenças Reumáticas/cirurgia , EscóciaRESUMO
BACKGROUND: Digital health technology (DHT) promises to support patients and healthcare professionals (HCPs) to optimize the management of chronic obstructive pulmonary disease (COPD). However, there is a lack of evidence demonstrating the effectiveness of DHT for the management of COPD. One reason for this is the lack of user-involvement in the development of DHT interventions in COPD meaning their needs and preferences are rarely accounted for in the design phase. Although HCP adoption issues have been identified in relation to DHT, little is known about the challenges perceived by HCPs providing care to COPD patients. Therefore, this study aims to qualitatively explore the barriers and facilitators HCPs perceive for the use of DHT in the management of COPD. METHODS: Participants (n = 32) were recruited using snowball sampling from two university hospitals and several general practitioner clinics. A semi-structured interview was conducted with each participant. NVivo 12 software was used to complete thematic analysis on the data. RESULTS: Themes identified include: data quality; evidence-based care; resource constraints; and digital literacy presented as barriers; and facilitators include the following themes: digital health training and education; improving HCP digital literacy; and Personalized prescribing. Patient-centered approaches, such as pulmonary rehabilitation and shared decision-making were suggested as implementation strategies to ease the adoption of digital health for the management of COPD. CONCLUSION: These findings contribute new insights about the needs and preferences of HCPs working in COPD regarding DHT. The findings can be used to help mitigate user-experience issues by informing the design of person-centered implementation and adoption strategies for future digital health interventions in COPD.
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Gerenciamento Clínico , Pessoal de Saúde , Doença Pulmonar Obstrutiva Crônica/terapia , Telemedicina/métodos , Atitude do Pessoal de Saúde , Humanos , Entrevistas como Assunto , Pesquisa Qualitativa , Telemedicina/normasRESUMO
Small solid precipitates (bubbles) of xenon in an aluminum matrix have been formed by ion implantation. Lattice images of this room-temperature inert gas solid were obtained using high-resolution phase-contrast electron microscopy. Many bubbles showed a high degree of crystalline perfection, but regions of defective crystallinity were observed in several cases.
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Data taken in aircraft transects of emissions plumes from rural U.S. coal-fired power plants were used to confirm and quantify the nonlinear dependence of tropospheric ozone formation on plume NO(x) (NO plus NO(2)) concentration, which is determined by plant NO(x) emission rate and atmospheric dispersion. The ambient availability of reactive volatile organic compounds, principally biogenic isoprene, was also found to modulate ozone production rate and yield in these rural plumes. Differences of a factor of 2 or greater in plume ozone formation rates and yields as a function of NO(x) and volatile organic compound concentrations were consistently observed. These large differences suggest that consideration of power plant NO(x) emission rates and geographic locations in current and future U.S. ozone control strategies could substantially enhance the efficacy of NO(x) reductions from these sources.