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1.
ACS Sustain Chem Eng ; 11(48): 16946-16954, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38076616

RESUMO

Carbon fiber-reinforced epoxy composites are used in multiple industries, including aerospace, automotive, and wind energy applications, due to their excellent strength-to-weight ratios and tunable material properties. Fortunately, recycling strategies for carbon fiber-based composites are emerging, with the primary focus on the recovery of fibers due to the cost and energy intensity in their production. In addition to fiber recovery, there is an opportunity to recycle the epoxy components such that ideal recycling strategies would yield both fibers and epoxy monomers for reuse. To that end, here we examine potassium tert-butoxide-mediated cleavage of C-O and C-N bonds in amine-cured epoxy resins. We accomplish this via developing model compounds that reflect both C-O and C-N linkages in amine-cured epoxy composites before expanding to both model linear thermoplastics and thermosets. We obtain excellent yields of both phenol (up to 97% molar yield) and amine products (up to 99 mol %) from aromatic and/or aliphatic amine-based model compounds. This system enables up to a quantitative yield of bisphenol A and up to 58% molar yield of aniline from model thermoplastic epoxy amines and 71% molar yield of BPA from a reaction with a thermoset substrate. These data correspond to a 15% mass recovery of BPA from a commercial epoxy thermoset.

2.
J Contin Educ Health Prof ; 43(4): 234-240, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37092547

RESUMO

INTRODUCTION: Blended learning has taken on new prominence in the fields of higher and continuing education, especially as programs have shifted in response to teaching in a global pandemic. The faculty at the Jönköping Academy's Masters in Quality Improvement and Leadership program has been offering a blended learning curriculum, based on four core design principles, since 2009. We studied key features of the enacted curriculum to understand conditions that can support an effective blended learning model. METHODS: We used a case study approach underpinned by interactive research. Document analysis, a focus group, individual interviews, and stimulated recall interviews were used for data collection. Themes were identified through qualitative content analysis and data reduction, data display, and conclusion drawing. RESULTS: We grouped data into six emergent themes that clarify the enacted curriculum of an established Master's program: focusing on a common purpose, developing technical and relational knowledge and skills, linking theory and practice in the workplace, leveraging collaboration for mutual benefit, concentrating on leadership and coaching, and applying a blended and interprofessional learning model. CONCLUSION: Educators faced with increased demands to be flexible and to offer opportunities for distance education can learn from this case example of effective teaching of quality improvement and leadership in a blended format.


Assuntos
Liderança , Melhoria de Qualidade , Humanos , Currículo , Docentes , Grupos Focais
3.
J Clin Nurs ; 29(3-4): 429-436, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31715045

RESUMO

BACKGROUND: Inpatient falls continue to be a significant clinical issue, and while malnutrition is a known risk factors for falls, few studies have investigated its association with inpatient falls. This study aimed to explore the independent association between malnutrition and fall risk as well as harm from falls in hospital inpatients. METHODS: Malnutrition identified in annual malnutrition audits was combined with inpatient fall data captured through the electronic patient incident reporting system in the 12 months following audit days. Audit data were available for 1,849 inpatients across 2011-2015, and covariate associations between age, gender, BMI, malnutrition, falls and harmful falls were analysed. The reporting of this paper is in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) recommendations (see Appendix S1). RESULTS: The prevalence of malnutrition was 32.4% (n = 543), and 171 (9.2%) inpatients experienced a fall with 0.7% (n = 13) categorised as harmful. In bivariate analysis, patients who fell were more likely to be older (median 79.0 vs. 70.0 years; p < .0001) or malnourished (40.9% vs. 31.5%; p = .021). Malnutrition (p < .0001) and having a lower BMI (p = .026) were significant predictors of harmful falls. Regression modelling demonstrated that only increasing age increased the likelihood of having an inpatient fall (OR 1.022 95% CI 1.021-1.046; p < .0001). Malnourished inpatients were almost 8 times more likely to have a harmful fall than those not malnourished (OR 7.94 95% CI 1.457-43.338; p = .017), independent of age and BMI. CONCLUSIONS: Malnourished patients are more likely to experience a harmful fall. Assessment of malnutrition should be incorporated into fall risk assessments as a way of highlighting those patients at greater risk and to link to nutritional care pathways.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Desnutrição/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Medição de Risco , Fatores de Risco
4.
Plant Dis ; 103(12): 3226-3233, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31573431

RESUMO

Previous research has demonstrated the efficacy of prescription fungicide programs, based upon Peanut Rx, to reduce combined effects of early leaf spot (ELS), caused by Passalora arachidicola (Cercospora arachidicola), and late leaf spot (LLS), caused by Nothopassalora personata (syn. Cercosporidium personatum), but the potential of Peanut Rx to predict each disease has never been formally evaluated. From 2010 to 2016, non-fungicide-treated peanut plots in Georgia and Florida were sampled to monitor the development of ELS and LLS. This resulted in 168 cases (unique combinations of Peanut Rx risk factors) with associated total leaf spot risk points ranging from 40 to 100. Defoliation ranged from 13.9 to 100%, and increased significantly with increasing total risk points (conditional R2 = 0.56; P < 0.001). Leaf spot onset (time in days after planting [DAP] when either leaf spot reached 1% lesion incidence), ELS onset, and LLS onset ranged from 29 to 140, 29 to 142, and 50 to 143 DAP, respectively, and decreased significantly with increasing risk points. Standardized AUDPC of ELS was significantly affected by risk points (conditional R2 = 0.53, P < 0.001), but not for LLS. After removing redundant Peanut Rx factors, planting date, rotation, historical leaf spot prevalence, cultivar, and field history were used as fixed effects in mixed effect regression models to evaluate their contribution to leaf spot, ELS or LLS prediction. Results from mixed effects regression confirmed that the selected Peanut Rx risk factors contributed to the variability of at least one measurement of development of combined or separate epidemics of ELS and LLS, but not all factors affected ELS and LLS equally. Historical leaf spot prevalence, a new potential preplant risk factor, was a consistent predictor of the dominant disease(s) observed in the field. Results presented here demonstrate that Peanut Rx is a very effective tool for predicting leaf spot onset regardless of which leaf spot is predominant, but also suggest that associated risk does not reflect the same development for each disease. These data will be useful for refining thresholds for differentiating high, moderate, and low risk fields, and reevaluating the timing of fungicide applications in reduced input programs with respect to disease onset.


Assuntos
Arachis , Ascomicetos , Agricultura , Arachis/microbiologia , Ascomicetos/fisiologia , Florida , Fungicidas Industriais , Georgia , Fatores de Risco , Estações do Ano
5.
Plant Dis ; 103(9): 2271-2276, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31287371

RESUMO

Sensitivity monitoring of Venturia effusa, cause of pecan scab, has revealed insensitivity to fentin hydroxide and tebuconazole, but recent research indicates that the insensitivity to fentin hydroxide is not stable. A study was undertaken to determine if a fitness cost may be responsible for this instability. In this study, experiments were conducted to evaluate fitness components and phenotypic stability of insensitivity of V. effusa to fentin hydroxide and tebuconazole. Conidial production, conidial germination, microcolony growth, sensitivity to osmotic stress, and sensitivity to oxidative stress in the absence of fungicide were compared for isolates with differing sensitivities to both fungicides. Percent conidial germination decreased linearly with increasing fentin hydroxide insensitivity, and microcolony growth on 1.0 mM H2O2 decreased linearly with increasing tebuconazole insensitivity. Stability of resistance was assessed on concentrations of 1.0, 3.0, and 10 µg/ml of both fungicides prior to and after five transfers on non-fungicide-amended medium. Tebuconazole insensitivity was stable after transfers, but fentin hydroxide insensitivity on 1.0 and 3.0 µg/ml decreased significantly after transfers, indicating instability. Here we provide evidence that in V. effusa tebuconazole insensitivity is stable and fentin hydroxide insensitivity is not. These results suggest that fentin-hydroxide-resistant V. effusa isolates have reduced conidial viability compared with sensitive isolates, which may allow the population to regain sensitivity in the absence of this frequently used fungicide.


Assuntos
Ascomicetos , Farmacorresistência Fúngica , Compostos Orgânicos de Estanho , Triazóis , Ascomicetos/efeitos dos fármacos , Compostos Orgânicos de Estanho/farmacologia , Triazóis/farmacologia
6.
Plant Dis ; 103(5): 990-995, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30893024

RESUMO

Field trials were conducted in 2015 and 2016 in Tifton, GA to determine the effects of planting dates (24 and 27 April, 4, 11, 19, and 26 May 2015; and 11, 18, and 25 April and 2, 9, and 16 May 2016), peanut (Arachis hypogaea) cultivar (Georgia-06G and Georgia-12Y), and seed treatment (nontreated and treated with azoxystrobin, fludioxonil, and mefenoxam) on epidemics of late leaf spot (Nothopassalora personata), plant populations, and peanut yield. Final severity and AUDPC of late leaf spot increased with later planting dates in both years. For most planting dates in 2015 and the final planting date in 2016, final leaf spot severity and AUDPC were lower for Georgia-12Y than for Georgia-06G. Seed treatment increased plant populations for the 27 April and 4 May planting dates in 2015 and across all other treatments in 2016. Yields were higher for Georgia-12Y than for Georgia-06G in both years. In 2015, yields of both cultivars decreased according to linear functions of day of year of planting date, but there was no effect of planting date on yield in 2016. The combination of early planting with Georgia-12Y shows potential utility for management of leaf spot in situations such as organic production where fungicide use is minimal.


Assuntos
Arachis , Ascomicetos , Fungicidas Industriais , Arachis/classificação , Arachis/microbiologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/fisiologia , Fungicidas Industriais/farmacologia , Georgia , Especificidade da Espécie , Fatores de Tempo
7.
Pest Manag Sci ; 75(11): 3093-3101, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30924240

RESUMO

BACKGROUND: Gummy stem blight (GSB) is a devastating disease of cucurbits that has been effectively managed with fungicide applications. However, the Stagonosporopsis spp. that cause GSB have rapidly evolved resistance to multiple classes of fungicides. To better understand the evolution and persistence of fungicide resistance in field populations, resistance profiles of unique and clonal genotypes of 113 Stagonosporopsis citrulli and 19 S. caricae isolates to four different fungicides were determined based on in vitro mycelial growth assays and molecular markers based on genes encoding fungicide targets. RESULTS: All 19 S. caricae isolates screened were resistant to tebuconazole and azoxystrobin, and sensitive to boscalid and fluopyram. All 113 S. citrulli isolates were sensitive to tebuconazole and sensitive to fluopyram, with one exception that was fluopyram-resistant. All isolates of S. citrulli except two were resistant to azoxystrobin. Phenotypic differences in response to boscalid were detected among S. citrulli isolates, but the phenotypes were not associated with multilocus genotypes (MLG) determined by 16 microsatellite loci. Additionally, isolates sharing the same MLG varied by SdhB genotype. A unique mutation of I229V in SdhB, a target of succinate dehydrogenase inhibitor fungicides, was detected for the fluopyram-resistant isolate of S. citrulli. CONCLUSION: Both the lack of association of fungicide resistance profiles with genetic similarity of isolates based on microsatellite loci and the finding that widely distributed MLG varied in fungicide resistance profiles suggest that independent evolutionary events for resistance to boscalid have likely occurred. Frequent genetic recombination within populations may be responsible for resistance to multiple fungicides. This study provides useful information for effectively managing both species of GSB fungi present in the southeastern USA and understanding the evolution of fungicide resistance within populations of plant-pathogenic fungi. © 2019 Society of Chemical Industry.


Assuntos
Ascomicetos/efeitos dos fármacos , Farmacorresistência Fúngica , Fungicidas Industriais/farmacologia , Doenças das Plantas/prevenção & controle , Estrobilurinas/farmacologia , Succinato Desidrogenase/antagonistas & inibidores , Ascomicetos/fisiologia , Citrullus/microbiologia , Desmetilação/efeitos dos fármacos , Florida , Georgia , Doenças das Plantas/microbiologia , Especificidade da Espécie
8.
Plant Dis ; 103(5): 841-845, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30806573

RESUMO

The quinone outside inhibitor (QoI) fungicides are known for their inherently high resistance risk owing to substitutions in amino acid residues 129, 137, or 143 of the cytochrome b gene of phytopathogens. In Venturia effusa, cause of pecan scab, an intron adjacent to position 143 likely reduces this risk; however, the effects of a recently discovered substitution at position 137 (G137S) are unknown. Traditional in vitro assays are not useful for determining sensitivity of isolates of V. effusa to the QoI fungicides, owing to the fungitoxic effects of required alternative oxidase inhibitors. A detached leaf assay was developed to quantify the sensitivity of 59 isolates to azoxystrobin: 45 wild-type isolates and 14 carrying G137S. Isolate EC50 values ranged from <0.0001 to 0.3047 µg/ml; EC50 values for wild-type isolates ranged from <0.0001 to 0.2007 µg/ml (median 0.0023 µg/ml), whereas EC50 values for G137S isolates ranged from 0.0033 to 0.3047 µg/ml (median 0.0178 µg/ml). The median EC50 value for G137S isolates was significantly greater than that of the wild-type isolates; however, there was overlap between the two groups. This is the first report of sensitivity of V. effusa isolates to a QoI fungicide and evidence of G137S as a potential mechanism of partial resistance. However, although a complete control failure is unlikely, the impact of this substitution on QoI efficacy in Georgia pecan orchards remains to be determined.


Assuntos
Substituição de Aminoácidos , Ascomicetos , Pirimidinas , Estrobilurinas , Ascomicetos/efeitos dos fármacos , Ascomicetos/genética , Complexo III da Cadeia de Transporte de Elétrons/química , Complexo III da Cadeia de Transporte de Elétrons/genética , Fungicidas Industriais/farmacologia , Georgia , Testes de Sensibilidade Microbiana , Folhas de Planta/microbiologia , Pirimidinas/farmacologia , Estrobilurinas/farmacologia
9.
Phytopathology ; 108(11): 1326-1336, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29771192

RESUMO

Scab (caused by Venturia effusa) is the major disease of pecan in the southeastern United States. There is no information available on the fine-scale population genetic diversity or the occurrence of clonal types at small spatial scales that provides insight into inoculum sources and dispersal mechanisms, and potential opportunity for sexual reproduction. To investigate fine-scale genetic diversity, four trees of cultivar Wichita (populations) were sampled hierarchically: within each tree canopy, four approximately evenly spaced terminals (subpopulations) were selected and up to six leaflets (sub-subpopulations) were sampled from different compound leaves on each terminal. All lesions (n = 1 to 8) on each leaflet were sampled. The isolates were screened against a panel of 29 informative microsatellite markers and the resulting multilocus genotypes (MLG) subject to analysis. Mating type was also determined for each isolate. Of 335 isolates, there were 165 MLG (clonal fraction 49.3%). Nei's unbiased measure of genetic diversity for the clone-corrected data were moderate to high (0.507). An analysis of molecular variance demonstrated differentiation (P = 0.001) between populations on leaflets within individual terminals and between terminals within trees in the tree canopies, with 93.8% of variance explained among isolates within leaflet populations. Other analyses (minimum-spanning network, Bayesian, and discriminant analysis of principal components) all indicated little affinity of isolate for source population. Of the 335 isolates, most unique MLG were found at the stratum of the individual leaflets (n = 242), with similar total numbers of unique MLG observed at the strata of the terminal (n = 170), tree (n = 166), and orchard (n = 165). Thus, the vast majority of shared clones existed on individual leaflets on a terminal at the scale of 10s of centimeters or less, indicating a notable component of short-distance dispersal. There was significant linkage disequilibrium (P < 0.001), and an analysis of Psex showed that where there were multiple encounters of an MLG, they were most probably the result of asexual reproduction (P < 0.05) but there was no evidence that asexual reproduction was involved in single or first encounters of an MLG (P > 0.05). Overall, the MAT1-1-1 and MAT1-2-1 idiomorphs were at equilibrium (73:92) and in most populations, subpopulations, and sub-subpopulations. Both mating types were frequently observed on the same leaflet. The results provide novel information on the characteristics of populations of V. effusa at fine spatial scales, and provide insights into the dispersal of the organism within and between trees. The proximity of both mating idiomorphs on single leaflets is further evidence of opportunity for development of the sexual stage in the field.


Assuntos
Ascomicetos/genética , Carya/microbiologia , Genes Fúngicos Tipo Acasalamento/genética , Variação Genética , Doenças das Plantas/microbiologia , Estruturas Genéticas , Genética Populacional , Genótipo , Desequilíbrio de Ligação , Repetições de Microssatélites/genética , Folhas de Planta/microbiologia , Sudeste dos Estados Unidos , Análise Espacial
10.
J Antimicrob Chemother ; 72(9): 2443-2446, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28575384

RESUMO

Background: Azole resistance in isolates of the fungus Aspergillus fumigatus has been associated with agricultural use of azole fungicides. Environmental isolation of resistant isolates has been reported in Asia, Africa, Europe and South America. Objectives: To determine whether A. fumigatus isolates containing TR34/L98H or TR46/Y121F/T289A can be found in fields in the USA treated with agricultural azoles. Methods: Crop debris was collected and screened for A. fumigatus. All A. fumigatus isolates were screened for azole resistance. The CYP51A gene of azole-resistant isolates was sequenced. The population structure of a subset of isolates was determined using microsatellite typing. Results: This article identifies azole-resistant A. fumigatus isolates containing the TR34/L98H mutation in an experimental peanut field that had been treated with azole fungicides. Conclusions: These findings suggest the development of resistance to azole antifungals in A. fumigatus may be present where agricultural azoles are used in the USA.


Assuntos
Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/isolamento & purificação , Azóis/farmacologia , Produtos Agrícolas , Microbiologia do Solo , Aspergilose/epidemiologia , Aspergilose/microbiologia , Aspergillus fumigatus/genética , Compostagem , Sistema Enzimático do Citocromo P-450/genética , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Fungicidas Industriais/efeitos adversos , Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Testes de Sensibilidade Microbiana , Repetições de Microssatélites , Mutação , Estados Unidos/epidemiologia
11.
Phytopathology ; 107(5): 607-619, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28414611

RESUMO

Venturia effusa is the most important pathogen of pecan in the southeastern United States. Little information exists on the population biology and genetic diversity of the pathogen. A hierarchical sampling of 784 isolates from 63 trees in 11 pecan orchards in the southeastern United States were screened against a set of 30 previously characterized microsatellite markers. Populations were collected from Georgia (n = 2), Florida (n = 1), Alabama (n = 2), Mississippi (n = 1), Louisiana (n = 1), Illinois (n = 1), Oklahoma (n = 1), Texas (n = 1), and Kansas (n = 1). Clonality was low in all orchard populations (≤10.1% of isolates), and there were consistently high levels of genotypic diversity (Shannon-Weiner's index = 3.49 to 4.59) and gene diversity (Nei's measure = 0.513 to 0.713). Analysis of molecular variance showed that, although 81% of genetic diversity occurred at the scale of the individual tree, 16% occurred between orchards and only 3% between trees within orchards. All populations could be differentiated from each other (P = 0.01), and various cluster analyses indicated that some populations were more closely related compared with other pairs of populations. This is indicative of some limited population differentiation in V. effusa in the southeastern United States. Bayesian and nearest-neighbor methods suggested eight clusters, with orchards from Georgia and Florida being grouped together. A minimum spanning tree of all 784 isolates also indicated some isolate identification with source population. Linkage disequilibrium was detected in all but one population (Kansas), although 8 of the 11 populations had <20% of loci at disequilibrium. A Mantel test demonstrated a relationship between physical and genetic distance between populations (Z = 11.9, r = 0.559, P = 0.001). None of the populations were at mutation-drift equilibrium. All but 3 of the 11 populations had a deficiency of gene diversity compared with that expected at mutation-drift equilibrium (indicating population expansion); the remaining populations had an excess of gene diversity compared with that expected at mutation-drift equilibrium (indicating a recent bottleneck). These observations are consistent with the known history of pecan and pecan scab, which is that V. effusa became an issue on cultivated pecan in the last approximately 120 years (recent population expansion). Recently reported mating type genes and the sexual stage of this fungus may help explain the observed population characteristics, which bear a strong resemblance to those of other well-characterized sexually reproducing ascomycete pathogens.


Assuntos
Ascomicetos/genética , Carya/microbiologia , Variação Genética , Doenças das Plantas/microbiologia , Genética Populacional , Genótipo , Desequilíbrio de Ligação , Repetições de Microssatélites/genética , Sudeste dos Estados Unidos
12.
Plant Dis ; 101(5): 785-793, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-30678570

RESUMO

Scab is the most damaging disease of pecan in the southeastern United States. Pecan trees can attain 44 m in height, so managing disease in the upper canopy is a problem. Fungicide is ordinarily applied using ground-based air-blast sprayers. Although mechanical hedge-pruning and topping of pecan is done for several reasons, improved management of scab is an important reason in the humid, wet Southeast. Resulting shoot growth on cut limbs of susceptible cultivars could lead to more severe scab. In three experiments over three years, we explored the effect of hedge-pruning trees to ∼12 to 14 m compared with non-hedge-pruned trees. All trees received fungicide treatments (air-blast sprays and ≤3 aerial applications). Hedge-pruning either had no effect, or increased or decreased scab severity only slightly on leaflets, immature, or mature fruit (a -9.95 to +14.63% difference in scab severity compared with the control). However, height in the canopy invariably had a large and significant effect on scab severity, and amounted to a 0.05 to 73.77% difference in severity between the lowest and highest sample in the canopy. Fruit weight depended on sample height, with fruit most often weighing less when collected at greater sample heights. A robust relationship between fruit weight and scab severity was found at the highest sample heights where scab was also most often severe (R2 = 0.21 to 0.67, P < 0.0001). Hedge-pruning and topping pecan tree canopies to manage tree size will enable better fungicide coverage, reducing risk of a scab epidemic as more of the canopy is assured efficacious fungicide spray coverage.

13.
Plant Dis ; 101(2): 366-371, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30681924

RESUMO

Fusarium wilt, incited by the fungus Fusarium oxysporum f. sp. niveum, is a soilborne disease that affects watermelon production worldwide. Approaches for effective management of Fusarium wilt in watermelon are limited. Studies conducted in recent years indicated that prothioconazole and thiophanate-methyl reduced the disease significantly under field conditions. However, effects of the fungicides on different life stages of F. oxysporum f. sp. niveum and potential existence of fungicide resistance in F. oxysporum f. sp. niveum populations are unknown. In the present study, effects of prothioconazole and thiophanate-methyl on mycelium growth and spore germination of F. oxysporum f. sp. niveum isolates collected in watermelon fields in Georgia were determined. In vitro mycelium growth studies indicated that all 100 isolates evaluated were sensitive to prothioconazole; the effective concentration that suppressed mycelium growth by 50% ranged from 0.75 to 5.69 µg/ml (averaged 1.62 µg/ml). In contrast, 33 and 4% of the isolates were resistant to thiophanate-methyl at 10 and 100 µg/ml, respectively. Microconidial germination assays showed that 36 and 64% of the isolates tested were sensitive or intermediately sensitive to prothioconazole at 100 µg/ml but the fungicide did not inhibit spore germination at 10 µg/ml. Sequencing a portion of the ß-tubulin gene of eight isolates resistant or sensitive to thiophanate-methyl indicated that fungicide resistance was associated with a point mutation at nucleotide position 200, resulting in a substitution of phenylalanine by tyrosine. This is the first report of isolates of F. oxysporum resistant to thiophanate-methyl. Results of the research suggest that prothioconazole may be a viable option for management of Fusarium wilt of watermelon whereas thiophanate-methyl should be used judiciously due to the existence of isolates resistant to the fungicide.

14.
Stand Genomic Sci ; 11: 36, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27274782

RESUMO

Pecan scab, caused by the plant pathogenic fungus Fusicladium effusum, is the most destructive disease of pecan, an important specialty crop cultivated in several regions of the world. Only a few members of the family Venturiaceae (in which the pathogen resides) have been reported sequenced. We report the first draft genome sequence (40.6 Mb) of an isolate F. effusum collected from a pecan tree (cv. Desirable) in central Georgia, in the US. The genome sequence described will be a useful resource for research of the biology and ecology of the pathogen, coevolution with the pecan host, characterization of genes of interest, and development of markers for studies of genetic diversity, genotyping and phylogenetic analysis. The annotation of the genome is described and a phylogenetic analysis is presented.

15.
Acad Med ; 91(3): 354-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26760058

RESUMO

PROBLEM: Current models of health care quality improvement do not explicitly describe the role of health professions education. The authors propose the Exemplary Care and Learning Site (ECLS) model as an approach to achieving continual improvement in care and learning in the clinical setting. APPROACH: From 2008-2012, an iterative, interactive process was used to develop the ECLS model and its core elements--patients and families informing process changes; trainees engaging both in care and the improvement of care; leaders knowing, valuing, and practicing improvement; data transforming into useful information; and health professionals competently engaging both in care improvement and teaching about care improvement. In 2012-2013, a three-part feasibility test of the model, including a site self-assessment, an independent review of each site's ratings, and implementation case stories, was conducted at six clinical teaching sites (in the United States and Sweden). OUTCOMES: Site leaders reported the ECLS model provided a systematic approach toward improving patient (and population) outcomes, system performance, and professional development. Most sites found it challenging to incorporate the patients and families element. The trainee element was strong at four sites. The leadership and data elements were self-assessed as the most fully developed. The health professionals element exhibited the greatest variability across sites. NEXT STEPS: The next test of the model should be prospective, linked to clinical and educational outcomes, to evaluate whether it helps care delivery teams, educators, and patients and families take action to achieve better patient (and population) outcomes, system performance, and professional development.


Assuntos
Educação Médica , Modelos Educacionais , Melhoria de Qualidade , Humanos , Avaliação de Resultados em Cuidados de Saúde , Participação do Paciente , Avaliação de Programas e Projetos de Saúde , Padrão de Cuidado , Suécia , Estados Unidos
16.
Plant Dis ; 100(10): 2106-2112, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30683001

RESUMO

Gummy stem blight (GSB) is a destructive disease of cucurbits caused by three closely related Stagonosporopsis species. In the southeastern United States, GSB management relies heavily on triazole fungicides. Our objectives were to determine if resistance to triazoles has developed in populations of GSB fungi in the southeastern United States, and if so, to investigate the molecular basis of resistance. A tebuconazole sensitivity assay was conducted on 303 Stagonosporopsis citrulli and 19 S. caricae isolates collected from the southeastern United States in 2013 and 2014, as well as three S. citrulli, three S. cucurbitacearum, and six S. caricae isolates from other regions or years. Tebuconazole resistance was detected for all 19 S. caricae isolates from the southeastern United States and one S. caricae isolate from Brazil. All S. citrulli and S. cucurbitacearum isolates were sensitive to tebuconazole. For resistant and sensitive isolates of S. caricae, coding and promoter regions of the target gene Cyp51 were sequenced and expression levels of Cyp51 and ScAtrG (an ATP-binding cassette transporter) were measured. Tebuconazole resistance was not associated with mutations within Cyp51, multiple copies of Cyp51, changes in the promoter region, or increased expression of Cyp51 or ScAtrG. Tebuconazole resistance may explain the increase in frequency of S. caricae isolates recovered from GSB-infected cucurbits in Georgia.

17.
Healthc Q ; 17(2): 29-32, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25191805

RESUMO

The Saskatchewan Ministry of Health has committed to a multi-million dollar investment toward the implementation of Lean methodology across the province's healthcare system. Originating as a production line discipline (the Toyota Production System), Lean has evolved to encompass process improvements including inventory management, waste reduction and quality improvement techniques. With an initial focus on leadership, strategic alignment, training and the creation of a supportive infrastructure (Lean promotion offices), the goal in Saskatchewan is a whole health system transformation that produces "better health, better value, better care, and better teams." Given the scope and scale of the initiative and the commitment of resources, it is vital that a comprehensive, longitudinal evaluation plan be implemented to support ongoing decision-making and program design. The nature of the initiative also offers a unique opportunity to contribute to health quality improvement science by advancing our understanding of the implementation and evaluation of complex, large-scale healthcare interventions. The purpose of this article is to summarize the background to Lean in Saskatchewan and the proposed evaluation methods.


Assuntos
Atenção à Saúde/organização & administração , Atenção à Saúde/legislação & jurisprudência , Humanos , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Qualidade da Assistência à Saúde/organização & administração , Saskatchewan , Gestão da Qualidade Total/organização & administração
18.
Plant Dis ; 98(12): 1681-1684, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30703889

RESUMO

Gummy stem blight (GSB), caused by the fungus Didymella bryoniae, is considered the most widespread and destructive disease of watermelon in the southeastern United States. The quinone outside-inhibiting (QoI) fungicide azoxystrobin (AZO), which inhibits mitochondrial respiration by binding to the outer, quinone-oxidizing pocket of the cytochrome bc1 (cyt b) enzyme complex, was initially very effective in controlling GSB. However, resistance to AZO has been observed in D. bryoniae in many watermelon-producing regions. In this study, the DNA sequences of partial cyt b genes of four AZO-resistant (AZO-R) and four AZO-sensitive (AZO-S) isolates of D. bryoniae confirmed the amino acid substitution of glycine by alanine at the 143 codon (G143A) in the AZO-R isolates tested. Allele-specific primers were designed to detect the resistant or sensitive allele at codon 143 of the cyt b gene, which amplified a 165-bp polymerase chain reaction (PCR) product from genomic DNA of nine AZO-R and nine AZO-S isolates of D. bryoniae, respectively. The primer pairs did not amplify DNA from other pathogens tested in the study. The results indicated that the PCR assays developed in the study were specific in differentiating AZO-R and AZO-S isolates and could facilitate AZO resistance detection in D. bryoniae.

19.
Pest Manag Sci ; 68(4): 645-51, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22076736

RESUMO

BACKGROUND: Didymella bryoniae has a history of developing resistance to single-site fungicides. A recent example is with the succinate-dehydrogenase-inhibiting fungicide (SDHI) boscalid. In laboratory assays, out of 103 isolates of this fungus, 82 and seven were found to be very highly resistant (B(VHR) ) and highly resistant (B(HR) ) to boscalid respectively. Cross-resistance studies with the new SDHI penthiopyrad showed that the B(VHR) isolates were only highly resistant to penthiopyrad (B(VHR) -P(HR) ), while the B(HR) isolates appeared sensitive to penthiopyrad (B(HR) -P(S) ). In this study, the molecular mechanism of resistance in these two phenotypes (B(VHR) -P(HR) and B(HR) -P(S) ) was elucidated, and their sensitivity to the new SDHI fluopyram was assessed. RESULTS: A 456 bp cDNA amplified fragment of the succinate dehydrogenase iron sulfur gene (DbSDHB) was initially cloned and sequenced from two sensitive (B(S) -P(S) ), two B(VHR) -P(HR) and one B(HR) -P(S) isolate of D. bryoniae. Comparative analysis of the DbSDHB protein revealed that a highly conserved histidine residue involved in the binding of SDHIs and present in wild-type isolates was replaced by tyrosine (H277Y) or arginine (H277R) in the B(VHR) -P(HR) and B(HR) -P(S) variants respectively. Further examination of the role and extent of these alterations showed that the H/Y and H/R substitutions were present in the remaining B(VHR) -P(HR) and B(HR) -P(S) variants respectively. Analysis of the sensitivity to fluopyram of representative isolates showed that both SDHB mutants were sensitive to this fungicide as the wild-type isolates. CONCLUSION: The genotype-specific cross-resistance relationships between the SDHIs boscalid and penthiopyrad and the lack of cross-resistance between these fungicides and fluopyram should be taken into account when selecting SDHIs for gummy stem blight management.


Assuntos
Ascomicetos/efeitos dos fármacos , Ascomicetos/genética , Benzamidas/farmacologia , Farmacorresistência Fúngica , Fungicidas Industriais/farmacologia , Doenças das Plantas/microbiologia , Piridinas/farmacologia , Sequência de Aminoácidos , Ascomicetos/isolamento & purificação , Ascomicetos/fisiologia , Compostos de Bifenilo/farmacologia , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Dados de Sequência Molecular , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Pirazóis/farmacologia , Alinhamento de Sequência , Succinato Desidrogenase/química , Succinato Desidrogenase/genética , Succinato Desidrogenase/metabolismo , Tiofenos/farmacologia
20.
J Nematol ; 43(3-4): 160-5, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23430318

RESUMO

Systemic acquired resistance (SAR) can be elicited by virulent and avirulent pathogenic strains and SAR against plant-parasitic nematodes has been documented. Our objective was to determine whether co-infection of cotton by Meloidogyne incognita and Rotylenchulus reniformis affects the population level of either nematode compared to infection by each species individually. Split-root trials were conducted in which plants were inoculated with i) R. reniformis only, ii) M. incognita only, iii) both R. reniformis and M. incognita, or iv) no nematodes. Half of the root system was inoculated with R. reniformis or M. incognita on day 0 and the other half with M. incognita or R. reniformis on day 0 or day 14 depending on the experiment. Experiments were conducted on cotton cultivar DP 0935 B2RF (susceptible to both nematodes), LONREN-1 (germplasm line resistant to R. reniformis), and M-120 RNR (germplasm line resistant to M. incognita), and tests were terminated 8 wk after the last inoculation. Both soil (vermiform) and roots (egg) extracted from each half of the root system to determine the total nematode population levels, and root galling was rated on a 0 to 10 scale. Mixed models analysis and comparison of least squares means indicated no differences in root galling (except on LONREN-1) or population levels when the two nematode species were introduced on the same day. When M. incognita was introduced 14 d after R. reniformis, reduction in galling (36% on DP 0935 and 33% on LONREN-1) and M. incognita population levels (35% on DP 0935 and 45% on LONREN-1) were significant (P ≤ 0.05). When R. reniformis was inoculated 14 d after M. incognita, reduction in R. reniformis population levels (18% on DP 0935 and 26% on M-120) were significant. This study documents for the first time that infection of cotton by a nematode can elicit SAR to another nematode species.

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