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1.
J Infect Dis ; 220(2): 254-265, 2019 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-30835266

RESUMEN

BACKGROUND: Human immunodeficiency virus type 1 (HIV-1) genetic diversity increases over the course of infection and can be used to infer the time since infection and, consequently, infection recency, which are crucial for HIV-1 surveillance and the understanding of viral pathogenesis. METHODS: We considered 313 HIV-infected individuals for whom reliable estimates of infection dates and next-generation sequencing (NGS)-derived nucleotide frequency data were available. Fractions of ambiguous nucleotides, obtained by population sequencing, were available for 207 samples. We assessed whether the average pairwise diversity calculated using NGS sequences provided a more exact prediction of the time since infection and classification of infection recency (<1 year after infection), compared with the fraction of ambiguous nucleotides. RESULTS: NGS-derived average pairwise diversity classified an infection as recent with a sensitivity of 88% and a specificity of 85%. When considering only the 207 samples for which fractions of ambiguous nucleotides were available, the NGS-derived average pairwise diversity exhibited a higher sensitivity (90% vs 78%) and specificity (95% vs 67%) than the fraction of ambiguous nucleotides. Additionally, the average pairwise diversity could be used to estimate the time since infection with a mean absolute error of 0.84 years, compared with 1.03 years for the fraction of ambiguous nucleotides. CONCLUSIONS: Viral diversity based on NGS data is more precise than that based on population sequencing in its ability to predict infection recency and provides an estimated time since infection that has a mean absolute error of <1 year.

2.
J Med Internet Res ; 17(10): e243, 2015 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-26508089

RESUMEN

BACKGROUND: Electronic cigarette (e-cigarette) use has increased in the United States, leading to active debate in the public health sphere regarding e-cigarette use and regulation. To better understand trends in e-cigarette attitudes and behaviors, public health and communication professionals can turn to the dialogue taking place on popular social media platforms such as Twitter. OBJECTIVE: The objective of this study was to conduct a content analysis to identify key conversation trends and patterns over time using historical Twitter data. METHODS: A 5-category content analysis was conducted on a random sample of tweets chosen from all publicly available tweets sent between May 1, 2013, and April 30, 2014, that matched strategic keywords related to e-cigarettes. Relevant tweets were isolated from the random sample of approximately 10,000 tweets and classified according to sentiment, user description, genre, and theme. Descriptive analyses including univariate and bivariate associations, as well as correlation analyses were performed on all categories in order to identify patterns and trends. RESULTS: The analysis revealed an increase in e-cigarette-related tweets from May 2013 through April 2014, with tweets generally being positive; 71% of the sample tweets were classified as having a positive sentiment. The top two user categories were everyday people (65%) and individuals who are part of the e-cigarette community movement (16%). These two user groups were responsible for a majority of informational (79%) and news tweets (75%), compared to reputable news sources and foundations or organizations, which combined provided 5% of informational tweets and 12% of news tweets. Personal opinion (28%), marketing (21%), and first person e-cigarette use or intent (20%) were the three most common genres of tweets, which tended to have a positive sentiment. Marketing was the most common theme (26%), and policy and government was the second most common theme (20%), with 86% of these tweets coming from everyday people and the e-cigarette community movement combined, compared to 5% of policy and government tweets coming from government, reputable news sources, and foundations or organizations combined. CONCLUSIONS: Everyday people and the e-cigarette community are dominant forces across several genres and themes, warranting continued monitoring to understand trends and their implications regarding public opinion, e-cigarette use, and smoking cessation. Analyzing social media trends is a meaningful way to inform public health practitioners of current sentiments regarding e-cigarettes, and this study contributes a replicable methodology.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina/estadística & datos numéricos , Internet/estadística & datos numéricos , Medios de Comunicación Sociales/estadística & datos numéricos , Femenino , Humanos , Opinión Pública , Cese del Hábito de Fumar , Estados Unidos
3.
Entramado ; 13(2): 250-257, jul.-dic. 2017. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1090152

RESUMEN

Resumen La gallinaza fresca, debido a su rápida disponibilidad está siendo ampliamente utilizada como fuente exclusiva de nutrientes, especialmente nitrógeno (N), en el cultivo de cebolla (Allium fistulosum), sin embargo, problemas de toxicidad por sales y acumulación de metales pesados en plantas han sido detectados. El objetivo de este trabajo fue estimar el efecto de la gallinaza fresca y compostada sobre las bacterias Azotobacter sp. y Azospirillum sp., así como en el número de esporas de hongos micorrízicos arbusculares (HMA), en el cultivo de cebolla. En el experimento se utilizó un diseño de bloques al azar con cuatro tratamientos y tres réplicas a partir de requerimientos en fertilización del cultivo y el análisis de suelos. Los tratamientos fueron: T1-Gallinaza fresca + Fertilizante foliar líquido quelatado-(14 Ton/ha=400 gr/ sitio gallinaza fresca + complejo biofertilizante a base de N, P y aminoácidos-1 L/ha.), T2-Gallinaza compostada + Fertilizante foliar líquido quelatado-14 Ton/ha=400 gr/sitio gallinaza fresca + (complejo biofertilizante a base de N, P y aminoácidos-1 L/ha.), T3-Fertilizante de síntesis química: fertirrigación con complejo de fertilizante 20-20-20 + elementos menores (10 g/sitio=350 kg/ha) y T4-Fertilizante de síntesis química: Aplicación en el suelo con complejo de fertilizante 20-20-20+elementos menores (20 g/sitio=700 kg/ha.). Los resultados obtenidos indican que la gallinaza cruda tiene un impacto positivo en el rendimiento del cultivo de cebolla y la esporulación de HMA (91 esporas por gamo de solo), un efecto negativo en Azotobacter sp. con mejor desarrollo en la gallinaza compostada (1,0 x107 UFC) y en Azospirillum sp. sin respuesta relevante, sin embargo fue más abundante que Azotobacter sp.en cada uno de los tratamientos.


Abstract Poultry manure application is highly used as exclusive nutrient sources, especially N, in anion culture (A. fistulosum), However there has been detected toxicity problems by salts and heavy metals in plants. The aim of this study was to estimate the effect of fresh poultry manure and composted on Azotobacter sp., Azospirillum sp. and arbuscular mycorrhizal fungi (AMF). The treatments were performed under completely randomized design with 4 treatments and 3 replications according to fertilization requirements and soil analysis. Treatments were formed as follows: Tl-Poultry manure + Foliar liquid fertilizer quelated-14 ton.ha-1=400 grsite-1 poultry manure + complex biofertilizer of N, P and aminoacids-1 L.ha-1, T2-Composted poultry manure + Foliar liquid fertilizer quelated-14 ton.ha-1=400 grsite-1 poultry manure + complex biofertilizer of N, P and aminoacids-1 L.ha-1, T3-Chemical fertilizer: fertirrigation with complex biofertilizer 20-20-20 + minor elements (l0 grsite-1 =350 kg ha-1) and T4-Chemical fertilizer: Application in the soil with complex biofertilizer 20-20-20 + minor elements (20 kg ha-1=700 kg ha-1.). We observed that anion culture and AMF spores (91 spores by 1g soil) have a significant respond to poultry manure. Azotobacter sp. was negatively affected by poultry manure but positively influenced by composted poultry manure (l.0 xl07 CFU). We no observed a relevant respond of Azospirillum sp., although, it was more abundant than Azotobacter sp. in all treatments.


Resumo O esterco de galinha fresco, pela sua rápida disponibilidade é utilizada como fornecedor de nutrientes, especialmente N, na cultura da cebola (A. fistulosum), No entanto, problemas de toxicidade por sais e acumulação de metais pesados em plantas tem sido detectado. O objetivo deste trabalho foi estimar o efeito do esterco de galinha fresco e decomposto sobre as bactérias Azotobacter sp. e Azospirillum sp. e o número de esporos de fungos micorrízicos arbusculares (FMA) na cultura da cebola. O delineamento experimental foi de blocos ao acaso, com quatro tratamento e três repetições, segundo os requerimentos nutricionais da cultura e a análise de solo. Os tratamentos foram os seguintes: Tl-Cama aviaria fresca + fertilizante foliar líquido quelatado- (14 Ton/ha=400 gr/local-cama aviaria fresca + complexo biofertilizante baseado em N, P y aminoácidos-1 L/ha.), T2-Cama aviaria + fertilizante foliar líquido quelatado-14 Ton/ha=400 gr/local-Cama aviaria + (complexo biofertilizante baseado em N, P y aminoácidos-1 L/ha.), T3-Fertilizante de síntese química: fertirrigação com complexo de fertilizante 20-20-20 + elementos menores (10 g/local=350 kg/ha) y T4-Fertilizante de síntese química: Aplicação no solo com complexo de fertilizante 20-20-20 + elementos menores (20 g/local=700 kg/ha.).Os resultados aqui obtidos mostram efeito positivo do esterco de galinha no rendimento da cultura da cebola e da esporulação dos HMA (91 esporos por gama de solo), efeito negativo em Azotobacter sp., se desenvolvendo melhor no esterco de galinha decomposta (1,0 x107 UFC) e sem resposta relevante em Azospirillum sp., embora tenha sido mais abundante do que Azotobacter sp. em todos os tratamentos.

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