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1.
Viruses ; 15(6)2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37376631

RESUMO

Foot-and-mouth disease (FMD), caused by the FMD virus (FMDV), is a highly contagious disease of cloven-hoofed livestock that can have severe economic impacts. Control and prevention strategies, including the development of improved vaccines, are urgently needed to effectively control FMD outbreaks in endemic settings. Previously, we employed two distinct strategies (codon pair bias deoptimization (CPD) and codon bias deoptimization (CD)) to deoptimize various regions of the FMDV serotype A subtype A12 genome, which resulted in the development of an attenuated virus in vitro and in vivo, inducing varying levels of humoral responses. In the current study, we examined the versatility of the system by using CPD applied to the P1 capsid coding region of FMDV serotype A subtype, A24, and another serotype, Asia1. Viruses carrying recoded P1 (A24-P1Deopt or Asia1-P1Deopt) exhibited different degrees of attenuation (i.e., delayed viral growth kinetics and replication) in cultured cells. Studies in vivo using a mouse model of FMD demonstrated that inoculation with the A24-P1Deopt and Asia1-P1Deopt strains elicited a strong humoral immune response capable of offering protection against challenge with homologous wildtype (WT) viruses. However, different results were obtained in pigs. While clear attenuation was detected for both the A24-P1Deopt and Asia1-P1Deopt strains, only a limited induction of adaptive immunity and protection against challenge was detected, depending on the inoculated dose and serotype deoptimized. Our work demonstrates that while CPD of the P1 coding region attenuates viral strains of multiple FMDV serotypes/subtypes, a thorough assessment of virulence and induction of adaptive immunity in the natural host is required in each case in order to finely adjust the degree of deoptimization required for attenuation without affecting the induction of protective adaptive immune responses.


Assuntos
Vírus da Febre Aftosa , Febre Aftosa , Vacinas Virais , Animais , Suínos , Sorogrupo , Anticorpos Antivirais/genética , Febre Aftosa/prevenção & controle , Proteínas do Capsídeo/genética , Vacinas Virais/genética
2.
Sci Total Environ ; 782: 145704, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33839674

RESUMO

This study examines the use of organic petrology techniques to quantify the amount of coal and carbonaceous combustion by-products (i.e., coke, coal tar/pitch, cenospheres) in sediments taken from the Kinnickinnic River adjacent to the former site of the Milwaukee Solvay Coke and Gas Company. These materials are of concern as contaminants like polycyclic aromatic hydrocarbons (PAHs) are known to readily adsorb to coal and combustion byproducts. Kinnickinnic River sediment samples (n = 36) ranging in depth (1-11 ft.) were collected from eight core locations to quantify and characterize carbonaceous material in the sediments. To determine the amount (vol%) of organic particulates, U.S. Geological Survey (USGS) modified the existing ASTM D2799 using the following categories: coal, coke, coal tar/pitch, inertinite organics, plant material, cenospheres, and mineral matter. Coal fragments were subdivided by rank using vitrinite reflectance (Ro, %) and organic components were further subdivided into the size fractions of coarse (250-1000 µm), fine (63-250 µm), and very fine (<63 µm). Of the 36 samples analyzed, concentrations of coal, coke, and coal tar/pitch ranged from 0 to 18.2 vol%, 0 to 32.0 vol%, and 0 to 2.6 vol%, respectively, with the highest concentrations occurring near point sources (e.g. discharge pipe and coal unloading operations). Samples that were furthest upstream and downstream from the Solvay site exhibited a marked decrease in particulate organics, with exception of one upstream location which had 19.8 vol% coke. Overall, the modified ASTM method provided a means to quantify the abundance of carbonaceous material present in the sediments. Petrography and total PAH concentrations did not provide a clear correlation to organic matter type or size fraction but the samples with the highest vol% organic matter in each core generally corresponded to the sample with the highest bulk PAH content.

3.
J Air Waste Manag Assoc ; 65(1): 27-40, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25946955

RESUMO

A study of a Powder River Basin (PRB) coal pile found that fugitive emissions from natural and human activity each produced similar levels of downwind fine + coarse (i.e., smaller than 10 µm, or PM10) particle mass concentrations. Natural impacts were statistically removed from downwind measurements to estimate emission factor Ev for bulldozers working on the pile. The Ev determined here was similar in magnitude to emission factors (EFs) computed using a U.S. Environmental Protection Agency (EPA) formulation for unpaved surfaces at industrial sites, even though the latter was not based on data for coal piles. EF formulations from this study and those in the EPA guidance yield values of similar magnitude but differ in the variables used to compute Ev variations. EPA studies included effects of surface silt fraction and vehicle weight, while the present study captured the influence of coal moisture. Our data indicate that the relationship between PRB coal fugitive dust Ev (expressed as mass of PM10 emitted per minute of bulldozer operation) and coal moisture content Mc (in percent) at the study site is best expressed as Ev =10(f(Mc())) where f(Mc) is a function of moisture. This function was determined by statistical regression between log10(Ev) and Mc where both Ev and Mc are expressed as daily averages of observations based on 289 hours sampled during 44 days from late June through mid-November of 2012. A methodology is described that estimates Mc based on available meteorological data (precipitation amount and solar radiation flux). An example is given of computed variations in daily Ev for an entire year. This illustrates the sensitivity of the daily average particulate EF to meteorological variability at one location. Finally, a method is suggested for combining the moisture-sensitive formulation for Ev with the EPA formulation to accommodate a larger number of independent variables that influence fugitive emissions.


Assuntos
Poeira/análise , Emissões de Veículos/análise , Carvão Mineral , Minas de Carvão , Modelos Teóricos , Tempo (Meteorologia)
4.
J Air Waste Manag Assoc ; 63(7): 806-18, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23926850

RESUMO

UNLABELLED: Dry fly ash disposal involves dropping ash from a truck and the movement of a heavy grader or similar vehicle across the ash surface. These operations are known to produce fugitive particulate emissions that are not readily quantifiable using standard emission measurement techniques. However there are numerous situations--such as applying for a source air permit--that require these emissions be quantified. Engineers traditionally use emission factors (EFs) derived from measurements of related processes to estimate fly ash disposal emissions. This study near a dry fly ash disposal site using state-of-the-art particulate monitoring equipment examines for the first time fugitive emissions specific to fly ash handling at an active disposal site. The study measured hourly airborne mass concentrations for particles smaller than 2.5 microm (PM2.5) and 10 microm (PM10) along with meteorological conditions and atmospheric turbidity at high temporal resolution to characterize and quantify fugitive fly ash emissions. Fugitive fly ash transport and dispersion were computed using the on-site meteorological data and a regulatory air pollutant dispersion model (AERMOD). Model outputs coupled with ambient measurements yielded fugitive fly ash EFs that averaged 96 g Mg(-1) (of ash processed) for the PM(c) fraction (= PM10 - PM2.5) and 18 g Mg(-1) for PM2.5. Median EFs were much lower due to the strongly skewed shape of the derived EF distributions. Fugitive EFs from nearby unpaved roads were also characterized. Our primary finding is that EFs for dry fly ash disposal are considerably less than EFs derived using US Environmental Protection Agency AP-42 Emissions Handbook formulations for generic aggregate materials. This appears to be due to a large difference (a factor of 10+) between fugitive vehicular EFs estimated using the AP-42 formulation for vehicles driving on industrial roads (in this case, heavy slow-moving grading equipment) and EFs derived by the current study. IMPLICATIONS: Fugitive fly ash emission factors (EFs) derived by this study contribute to the small existing knowledge base for a type of pollutant that will become increasingly important as ambient particulate standards become tighter. In areas that are not in attainment with standards, realistic EFs can be used for compliance modeling and can help identify which classes of sources are best targeted to achieve desired air quality levels. In addition, understanding the natural variability in fugitive fly ash emissions can suggest methods that are most likely to be successful in controlling fugitive emissions related to dry fly ash storage.


Assuntos
Poluentes Atmosféricos/análise , Cinza de Carvão/análise , Monitoramento Ambiental/métodos , Incineração , Material Particulado/análise , Poluição do Ar/prevenção & controle , Alabama , Monitoramento Ambiental/normas , Modelos Teóricos , Tamanho da Partícula , Fatores de Tempo , Vento
5.
Environ Sci Technol ; 45(11): 4817-23, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21545154

RESUMO

The relative roles of natural and anthropogenic sources in determining ozone and fine particle concentrations over the continental United States (U.S.) are investigated using an expanded emissions inventory of natural sources and an updated version of the Community Multiscale Air Quality (CMAQ) model. Various 12-month CMAQ simulations for the year 2002 using different sets of input emissions data are combined to delineate the contributions of background pollutants (i.e., model boundary conditions), natural emissions, anthropogenic emissions, as well as the specific impacts of lightning and wildfires. Results are compared with observations and previous air quality model simulations. Wildfires and lightning are both identified as contributing significantly to ozone levels with lightning NO(x) adding as much as 25-30 ppbV (or up to about 50%) to surface 8-h average natural O(3) mixing ratios in the southeastern U.S. Simulated wildfire emissions added more than 50 ppbV (in some cases >90%) to 8-h natural O(3) at several locations in the west. Modeling also indicates that natural emissions (including biogenic, oceanic, geogenic and fires) contributed ≤ 40% to the annual average of total simulated fine particle mass over the eastern two-thirds of the U.S. and >40% across most of the western U.S. Biogenic emissions are the dominant source of particulate mass over the entire U.S. and wildfire emissions are secondary. Averaged over the entire modeling domain, background and natural ozone are dominant with anthropogenically derived ozone contributing up to a third of the total only during summer. Background contributions to fine particle levels are relatively insignificant in comparison. Model results are also contrasted with the U.S. Environmental Protection Agency (EPA) default values for natural light scattering particle concentrations to be used for regional haze regulatory decision-making. Regional differences in EPA guidance are not supported by the modeling and EPA uncertainty estimates for default values are far smaller than the modeled variability in natural particle concentrations.


Assuntos
Modelos Químicos , Ozônio , Material Particulado , Poluição do Ar/legislação & jurisprudência , Incêndios , Raio , Estados Unidos , United States Environmental Protection Agency
6.
J Am Geriatr Soc ; 58(9): 1780-5, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20863337

RESUMO

Providing practicing physicians with effective education that leads to better patient outcomes remains challenging. In 2003, the University of Cincinnati College of Medicine developed a comprehensive program to enhance practicing physician geriatric medicine education based on the Assessing the Care of Vulnerable Elders model. The program was implemented with a large, multisite primary care group based in the greater Cincinnati area and was designed to increase physicians' clinical skills and assist them in implementing new office and system strategies that could improve the quality of care for their older patients. Four topic areas were chosen: medication management, falls and mobility, urinary incontinence, and dementia. A multifaceted physician education program was developed for each topic area, with lunch-time, in-office, geriatrician-led presentations as the primary intervention. Over a 4-year period (2004-2007), more than 60 physicians in 16 primary care practices attended 107 teaching sessions. The value of the presentation content, quality of the presentations, and perception of meeting the primary care physicians' (PCPs') educational needs were each rated at 3.8 or above (4=excellent). Between 80% and 92% of the PCPs planned to make a change in their practice behavior as a result of the training, but only two offices initiated formal quality improvement projects. During the teaching sessions, the PCPs were provided with screening tools to identify "at risk" patients, assessment chart templates, and community resource and patient education materials. The application of a modified version of the ACOVE model to reach a large group of primary care physicians is possible and may be one strategy to improve the assessment and management of geriatric syndromes.


Assuntos
Educação Médica Continuada/métodos , Avaliação Geriátrica/métodos , Geriatria/educação , Médicos de Família/educação , Atenção Primária à Saúde/organização & administração , Garantia da Qualidade dos Cuidados de Saúde/métodos , Populações Vulneráveis , Idoso , Humanos , Ohio , Estudos Retrospectivos , Recursos Humanos
7.
Curr Cancer Drug Targets ; 7(2): 157-67, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17346107

RESUMO

PV701 is a naturally-attenuated, non-recombinant, oncolytic strain of Newcastle disease virus that displays preclinical intravenous (IV) efficacy. PV701 is selective at killing human cancer cells versus normal human cells based on tumor specific defects in the interferon (IFN)-mediated antiviral response. This oncolytic virus displays a broad spectrum of antitumor activity in vitro and in vivo. Preclinical models successfully predicted key clinical parameters including the mechanism of toxicity, two complementary strategies (desensitization and slow infusion) to reduce toxicity, and the starting dose for phase 1 trials. In three phase 1 trials of 114 patients using IV administration of PV701, Wellstat Biologics Corporation has evaluated the effects of dose, schedule, and infusion rate for PV701. Three general classes of side effects were seen: flu-like symptoms; tumor-site-specific adverse events (AEs); and infusion reactions. The first PV701 dose desensitized the patient to the side effects of further doses, allowing a marked increase in the maximum tolerated dose for subsequent doses compared to the first dose. Tumor responses were first noted at the higher doses achieved using desensitization. In the most recent phase 1 trial of 19 patients at Hamilton, Ontario, that employed desensitization, high repeat doses, and a slower infusion rate (Hamilton Regimen), there were six responses (4 major; 2 minor) and a total of six patients with survival for at least 2 years. In addition, patient tolerability improved using the Hamilton Regimen compared to IV bolus dosing used previously. Phase 2 studies of this novel biologic agent are about to begin.


Assuntos
Neoplasias/terapia , Vírus da Doença de Newcastle , Terapia Viral Oncolítica , Animais , Ensaios Clínicos Fase I como Assunto/métodos , Humanos , Infusões Intravenosas , Injeções Intravenosas , Vírus da Doença de Newcastle/genética , Vírus da Doença de Newcastle/fisiologia , Terapia Viral Oncolítica/efeitos adversos , Projetos de Pesquisa , Resultado do Tratamento , Replicação Viral
8.
Appetite ; 44(1): 83-92, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15604035

RESUMO

The extent to which general parenting represents feeding styles in ethnically diverse populations is not well documented. Existing measures of child feeding have focused almost exclusively on specific behaviors of European-American parents. A valid and reliable instrument was developed to identify feeding styles in parents of low-income minority preschoolers. Two hundred thirty-one parents (130 Hispanic; 101 African-American) completed questionnaires on feeding practices and parenting styles. Based on self-reported feeding behavior, parents were assigned to four feeding styles (authoritarian, n=84; authoritative, n=34; indulgent, n=80; and uninvolved, n=33). Convergent validity was evaluated by relating feeding styles to independent measures of general parenting and authoritarian feeding practices. Authoritarian feeding styles were associated with higher levels of general parental control and authoritarian feeding practices. Alternatively, authoritative feeding styles were associated with higher levels of general parental responsiveness. Among the two permissive feeding styles, Hispanic parents were more likely to be indulgent, whereas African-American parents were more likely to be uninvolved. Further, differences were found among the feeding styles on an independent measure of child's body mass index.


Assuntos
Negro ou Afro-Americano , Ingestão de Alimentos/psicologia , Família/psicologia , Hispânico ou Latino , Poder Familiar/etnologia , Poder Familiar/psicologia , Índice de Massa Corporal , Pré-Escolar , Ingestão de Alimentos/fisiologia , Feminino , Humanos , Masculino , Relações Pais-Filho/etnologia , Inquéritos e Questionários , Texas
9.
Environ Sci Technol ; 38(2): 570-80, 2004 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-14750734

RESUMO

An air quality model, URM-1ATM, was used to investigate tendencies in fine particle (PM2.5) species in response to changes in SO2 and NOx emissions in the eastern United States. The model employed the decoupled direct method (DDM) to estimate sensitivities without the need for multiple model runs for different emissions species and geographic regions. The baseline for sensitivities was emissions projected to 2010. Principal geographic regions investigated were east of the Mississippi River, although the contribution of a region to the immediate west of the river was also included in the study. Sensitivities to emissions changes from point sources (SO2 and NOx) and low-level sources (NOx) were computed. PM2.5 species examined were sulfate, organic carbon, and nitrate as well as total fine mass. Results for the midwest, mid-Atlantic, and southeast regions indicated that those regions affect their own aerosol levels the most. Aerosols in the northeast were most strongly linked to emissions from the midwest and mid-Atlantic regions. In general, midwest emissions had the most influence of any region on other regions. In addition, the southeast was relatively isolated, having the least influence outside itself and being least affected by neighboring regions. Sulfate was the species most sensitive to emission changes. Finally, the largest potential relative sensitivities of sulfate and organic aerosols, along with PM2.5 mass, to emissions changes were usually modeled to occur outside those areas computed to experience the highest aerosol levels.


Assuntos
Poluentes Atmosféricos/análise , Modelos Teóricos , Óxidos de Nitrogênio/análise , Dióxido de Enxofre/análise , Aerossóis , Monitoramento Ambiental , Tamanho da Partícula , Sensibilidade e Especificidade , Estados Unidos
10.
J Air Waste Manag Assoc ; 53(2): 168-84, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12617291

RESUMO

Site and regional trends in seasonally averaged particle SO4(2-) concentrations were examined for a large portion of the United States using data collected by the CASTNet air monitoring network. Trends were analyzed for overlapping periods of 1988-1999 and 1992-1999. The largest absolute SO4(2-) decreases--approximately -0.4 microg/m3/yr--between 1988 and 1999 occurred in summer for sites in the Ohio River Valley and areas to the east. Generally, the largest SO4(2-) reductions were found for summer, but larger relative reductions often occurred for spring and autumn. Sulfate changes during 1992-1999 were quite different from those found for 1988-1999 and were not entirely consistent with changes in SO2 emissions. In some locations, the 1992-1999 period saw smaller declines in SO4(2-), while in other places seasonal SO4(2-) actually increased. Increases were mostly confined to summer and autumn across the southern and southwestern states. Multivariate analysis of ambient sulfur levels, by region, versus SO2 emissions reveals that annual emissions are associated with more than 80% of the variance in seasonal sulfur (SO2 and SO4(2-)) in more than three-quarters of the cases examined. The weakest associations were found for the southeastern United States.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Sulfatos/análise , Poluição do Ar/prevenção & controle , Meio Ambiente , Monitoramento Ambiental , Tamanho da Partícula , Estações do Ano , Dióxido de Enxofre/análise , Estados Unidos
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