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1.
J Frailty Aging ; 9(3): 172-178, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32588033

RESUMEN

BACKGROUND: The Home Delivered Meals Program (HDMP) serves a vulnerable population of adults aged 60 and older who may benefit from technological services to improve health and social connectedness. OBJECTIVE: The objectives of this study are (a) to better understand the needs of HDMP participants, and (b) to characterize the technology-readiness and the utility of delivering information via the computer. DESIGN: We analyzed data from the 2017 NSOAAP to assess the health and functional status and demographic characteristics of HDMP participants. We also conducted a telephone survey to assess technology use and educational interests among NYC HDMP participants. MEASUREMENTS: Functional measures of the national sample included comorbidities, recent hospitalizations, and ADL/IADL limitations. Participants from our local NYC sample completed a modified version of the validated Computer Proficiency Questionnaire. Technology readiness was assessed by levels of technology use, desired methods for receiving health information, and interest in learning more about virtual senior centers. RESULTS: About one-third (32.4%) of national survey HDMP participants (n=902) reported insufficient resources to buy food and 17.1% chose between food or medications. Within the NYC HDMP participant survey sample (n=33), over half reported having access to the internet (54.5%), 48.5% used a desktop or laptop, and 30.3% used a tablet, iPad, or smartphone. CONCLUSION: The HDMP provides an opportunity to reach vulnerable older adults and offer additional resources that can enhance social support and improve nutrition and health outcomes. Research is warranted to compare technological readiness of HDMP participants across urban and rural areas in the United States.


Asunto(s)
Servicios de Alimentación/organización & administración , Servicios de Atención de Salud a Domicilio/organización & administración , Evaluación de Necesidades , Poblaciones Vulnerables , Anciano , Humanos , Persona de Mediana Edad , Ciudad de Nueva York , Estado Nutricional , Evaluación de Programas y Proyectos de Salud , Apoyo Social , Encuestas y Cuestionarios , Tecnología/estadística & datos numéricos , Estados Unidos
2.
J Frailty Aging ; 7(3): 182-186, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30095149

RESUMEN

BACKGROUND: Through diet and exercise interventions, community centers offer an opportunity to address health-related issues for some of the oldest, most vulnerable members of our society. OBJECTIVES: The purpose of this investigation is to draw upon nationwide data to better characterize the population served by the congregate meals program and to gather more detailed information on a local level to identify opportunities for service enhancement to improve the health and well-being of older adults. DESIGN: We examined community center data from two sources: 2015 National Survey of Older Americans Act and surveys from two New York City community centers. To assess nationwide service delivery, we analyzed participant demographics, functional status defined by activities of daily living, and perceptions of services received. MEASUREMENTS: Participants from the two New York City community centers completed a four-day food record. Functional measures included the short physical performance battery, self-reported physical function, grip strength, and the Montreal Cognitive Assessment. RESULTS: Nationwide (n=901), most participants rated the meal quality as good to excellent (91.7%), and would recommend the congregate meals program to a friend (96.0%). Local level data (n=22) were collected for an in-depth understanding of diet, physical activity patterns, body weight, and objective functional status measures. Diets of this small, local convenience sample were higher in fat, cholesterol, and sodium, and lower in calcium, magnesium, and fiber than recommended by current United States Dietary Guidelines. Average time engaged in moderate physical activity was 254 minutes per week (SD=227), exceeding the recommended 150 minutes per week, but just 41% (n=9) and 50% (n=11) of participants engaged in strength or balance exercises, respectively. CONCLUSION: Research is warranted to test whether improvements in the nutritional quality of food served and access/supports for engaging in strength training within community centers could help older adults achieve diet and physical activity recommendations.


Asunto(s)
Dieta , Ejercicio Físico , Servicios de Alimentación , Poblaciones Vulnerables , Anciano , Adhesión a Directriz , Guías como Asunto , Humanos , Política Nutricional , Evaluación de Programas y Proyectos de Salud , Encuestas y Cuestionarios , Estados Unidos
4.
J Hum Hypertens ; 31(7): 462-473, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28205551

RESUMEN

Measurement error in assessment of sodium and potassium intake obscures associations with health outcomes. The level of this error in a diverse US Hispanic/Latino population is unknown. We investigated the measurement error in self-reported dietary intake of sodium and potassium and examined differences by background (Central American, Cuban, Dominican, Mexican, Puerto Rican and South American). In 2010-2012, we studied 447 participants aged 18-74 years from four communities (Miami, Bronx, Chicago and San Diego), obtaining objective 24-h urinary sodium and potassium excretion measures. Self-report was captured from two interviewer-administered 24-h dietary recalls. Twenty percent of the sample repeated the study. We examined bias in self-reported sodium and potassium from diet and the association of mismeasurement with participant characteristics. Linear regression relating self-report with objective measures was used to develop calibration equations. Self-report underestimated sodium intake by 19.8% and 20.8% and potassium intake by 1.3% and 4.6% in men and women, respectively. Sodium intake underestimation varied by Hispanic/Latino background (P<0.05) and was associated with higher body mass index (BMI). Potassium intake underestimation was associated with higher BMI, lower restaurant score (indicating lower consumption of foods prepared away from home and/or eaten outside the home) and supplement use. The R2 was 19.7% and 25.0% for the sodium and potassium calibration models, respectively, increasing to 59.5 and 61.7% after adjusting for within-person variability in each biomarker. These calibration equations, corrected for subject-specific reporting error, have the potential to reduce bias in diet-disease associations within this largest cohort of Hispanics in the United States.


Asunto(s)
Potasio en la Dieta/orina , Autoinforme , Sodio en la Dieta/orina , Adulto , Anciano , Biomarcadores/orina , Calibración , Estudios de Cohortes , Femenino , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
5.
J Nutr Health Aging ; 20(8): 790-796, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27709227

RESUMEN

OBJECTIVE: Studies suggest protein intake may be associated with lower body weight, but protein has also been associated with preservation of lean body mass. Understanding the role of protein in maintaining health for older adults is important for disease prevention among this population. DESIGN: Cross-sectional study of the relationship of dietary protein on body composition. SETTING: New York City community centers. PARTICIPANTS: 1,011 Black, White, and Latino urban men and women 60-99 years of age. MEASUREMENTS: Protein intake was assessed using two interviewer-administered 24-hour recalls, and body composition was assessed using bioelectrical impedance analysis (BIA) of fat mass (kg) (FM), fat free mass (kg) (FFM), and impedance resistance (Ohms). STATISTICAL ANALYSIS: Indices of FM and FFM were calculated by dividing BIA measurements by height squared (m2), and percent FFM was calculated by dividing FFM by the sum of FM and FFM. Log linear models adjusting for age (continuous), race/ethnicity, education, physical activity (dichotomized at the median), hypertension, diabetes, and total calories (continuous). RESULTS: Just 33% of women and 50% of men reported meeting the RDA for protein. Both fat free mass index (FFMI) and fat mass index (FMI) were negatively associated with meeting the RDA for protein (Women: FFMI -1.78 95%CI [-2.24, -1.33], FMI -4.12 95% CI [-4.82, -3.42]; Men: FFMI -1.62 95% CI [-2.32, -0.93] FMI -1.80 95% CI [-2.70, -0.89]). After accounting for confounders, women and men consuming at least 0.8 g/kg/day had a 6.2% (95% CI: 5.0%, 7.4%) and a 3.2% (95% CI 1.1%, 5.3%) higher percent fat free mass, respectively. CONCLUSIONS: FFM, FFMI, FM, and FMI were inversely related to meeting the RDA for protein. Meeting the RDA for protein of at least 0.8g/kg/day was associated with a higher percentage of fat free mass among older adults. These results suggest meeting the protein recommendations of at least 0.8 g/kg/day may help to promote lower overall body mass, primarily through loss of fat mass rather than lean mass.


Asunto(s)
Sistema Cardiovascular , Proteínas en la Dieta/química , Ingesta Diaria Recomendada , Anciano , Anciano de 80 o más Años , Envejecimiento , Composición Corporal , Estudios Transversales , Impedancia Eléctrica , Planificación Ambiental , Femenino , Humanos , Masculino , Persona de Mediana Edad
6.
J Intellect Disabil Res ; 60(12): 1153-1164, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27561378

RESUMEN

BACKGROUND: Little is known about inpatient psychiatric hospitalisation among adults with intellectual disability (ID) in the United States. Greater research is, therefore, required to inform efforts aimed at preventing this costly and restrictive form of care. METHODS: Data were from 3299 individuals with ID (mean age = 31 years; SD = 14 years) who were referred to START (Systemic, Therapeutic, Assessment, Resources, and Treatment), a community-based crisis intervention and prevention programme. A random effects logistic regression model was used to examine the association between 11 factors and caregiver report of psychiatric hospitalisation in the past 12 months. RESULTS: Twenty eight percent of the sample had at least one psychiatric inpatient stay in the prior year. Factors associated with an increased likelihood of prior hospitalisation included: younger age, diagnosis of a psychotic disorder, a score of >30 on the irritability subscale of the Aberrant Behavior Checklist, increasing number of psychiatric diagnoses, less severe ID, Black/AA race and not having a home and community waiver. CONCLUSIONS: Among this high-risk referred group, more than 1 in 4 individuals were hospitalised in the year prior to referral. While results from the analyses will help profile those at risk for hospitalisation, the findings suggest that interventions at the policy level may play an important role in reducing psychiatric hospitalisation.


Asunto(s)
Servicios Comunitarios de Salud Mental/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Hospitales Psiquiátricos/estadística & datos numéricos , Discapacidad Intelectual/terapia , Adolescente , Adulto , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Discapacidad Intelectual/epidemiología , Masculino , Persona de Mediana Edad , Derivación y Consulta/estadística & datos numéricos , Estados Unidos/epidemiología , Adulto Joven
7.
Public Health Nutr ; 19(18): 3256-3264, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27339078

RESUMEN

OBJECTIVE: Measurement error in self-reported total sugars intake may obscure associations between sugars consumption and health outcomes, and the sum of 24 h urinary sucrose and fructose may serve as a predictive biomarker of total sugars intake. DESIGN: The Study of Latinos: Nutrition & Physical Activity Assessment Study (SOLNAS) was an ancillary study to the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) cohort. Doubly labelled water and 24 h urinary sucrose and fructose were used as biomarkers of energy and sugars intake, respectively. Participants' diets were assessed by up to three 24 h recalls (88 % had two or more recalls). Procedures were repeated approximately 6 months after the initial visit among a subset of ninety-six participants. SETTING: Four centres (Bronx, NY; Chicago, IL; Miami, FL; San Diego, CA) across the USA. SUBJECTS: Men and women (n 477) aged 18-74 years. RESULTS: The geometric mean of total sugars was 167·5 (95 % CI 154·4, 181·7) g/d for the biomarker-predicted and 90·6 (95 % CI 87·6, 93·6) g/d for the self-reported total sugars intake. Self-reported total sugars intake was not correlated with biomarker-predicted sugars intake (r=-0·06, P=0·20, n 450). Among the reliability sample (n 90), the reproducibility coefficient was 0·59 for biomarker-predicted and 0·20 for self-reported total sugars intake. CONCLUSIONS: Possible explanations for the lack of association between biomarker-predicted and self-reported sugars intake include measurement error in self-reported diet, high intra-individual variability in sugars intake, and/or urinary sucrose and fructose may not be a suitable proxy for total sugars intake in this study population.


Asunto(s)
Encuestas sobre Dietas , Sacarosa en la Dieta/administración & dosificación , Hispánicos o Latinos , Azúcares/administración & dosificación , Adolescente , Adulto , Anciano , Biomarcadores/orina , Sacarosa en la Dieta/orina , Ingestión de Energía , Femenino , Fructosa/orina , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Autoinforme , Estados Unidos , Adulto Joven
9.
Placenta ; 36(8): 790-5, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26162698

RESUMEN

UNLABELLED: Imprinted genes, which are monoallelically expressed by virtue of an epigenetic process initiated in the germline, are known to play key roles in regulating fetal growth and placental development. Numerous studies are investigating the expression of these imprinted genes in the human placenta in relation to common complications of pregnancy such as fetal growth restriction and preeclampsia. This study aimed to determine whether placental sampling protocols or other factors such as fetal sex, gestational age and mode of delivery may influence the expression of imprinted genes predicted to regulate placental signalling. METHODS: Term placentas were collected from Caucasian women delivering at University Hospital of Wales or Royal Gwent Hospital within two hours of delivery. Expression of the imprinted genes PHLDA2, CDKN1C, PEG3 and PEG10 was assayed by quantitative real time PCR. Intraplacental gene expression was analysed (N = 5). Placental gene expression was compared between male (N = 11) and female (N = 11) infants, early term (N = 8) and late term (N = 10) deliveries and between labouring (N = 13) and non-labouring (N = 21) participants. RESULTS: The paternally expressed imprinted genes PEG3 and PEG10 were resilient to differences in sampling site, fetal sex, term gestational age and mode of delivery. The maternally expressed imprinted gene CDKN1C was elevated over 2-fold (p < 0.001) in placenta from labouring deliveries compared with elective caesarean sections. In addition, the maternally expressed imprinted gene PHLDA2 was elevated by 1.8 fold (p = 0.01) in samples taken at the distal edge of the placenta compared to the cord insertion site. CONCLUSION: These findings support the reinterpretation of existing data sets on these genes in relation to complications of pregnancy and further reinforce the importance of optimising and unifying placental collection protocols for future studies.


Asunto(s)
Inhibidor p57 de las Quinasas Dependientes de la Ciclina/genética , Parto Obstétrico/métodos , Impresión Genómica , Factores de Transcripción de Tipo Kruppel/genética , Proteínas Nucleares/genética , Placenta/metabolismo , Proteínas/genética , Adulto , Proteínas Reguladoras de la Apoptosis , Inhibidor p57 de las Quinasas Dependientes de la Ciclina/metabolismo , Proteínas de Unión al ADN , Femenino , Regulación del Desarrollo de la Expresión Génica , Edad Gestacional , Humanos , Factores de Transcripción de Tipo Kruppel/metabolismo , Masculino , Proteínas Nucleares/metabolismo , Embarazo , Proteínas/metabolismo , Proteínas de Unión al ARN , Factores Sexuales , Adulto Joven
10.
J Parasitol ; 99(5): 743-7, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23656487

RESUMEN

There is a growing body of evidence that habitat fragmentation resulting from anthropogenic land use can alter the transmission dynamics of infectious disease. Baylisascaris procyonis , a parasitic roundworm with the ability to cause fatal central nervous system disease in many mammals, including humans, is a zoonotic threat, and research suggests that parasite recruitment rates by intermediate hosts are highly variable among forest patches in fragmented landscapes. During 2008, we sampled 353 white-footed mice ( Peromyscus leucopus ) from 22 forest patches distributed throughout a fragmented agricultural ecosystem to determine the influence of landscape-level habitat attributes on infection rates of B. procyonis in mice. We characterized each mouse in terms of infection status and intensity of infection, and calculated (on a patch-wide basis) prevalence, mean abundance of B. procyonis , and mean intensity of infection. We used an information-theoretic approach to develop a suite of candidate models characterizing the influence of landscape attributes on each of our measured characteristics of B. procyonis infection in white-footed mice, based on previous knowledge of raccoon ( Procyon lotor ) ecology and B. procyonis distribution in agricultural ecosystems. We observed evidence of B. procyonis infection in mice across all 22 habitat patches sampled. However, parasite recruitment rates and intensity were highly variable among patches, and the results of our analyses suggest that spatial variability in B. procyonis infections was primarily driven by emergent properties of fragmented ecosystems. In particular, prevalence, abundance, and intensity of B. procyonis infections in mice were negatively associated with the size and connectivity of forest patches. These results support previous studies indicating that habitat fragmentation can alter the transmission dynamics of infectious disease, and suggest that factors below the scale of landscape, i.e., fine-scale habitat structure or demographic and behavioral attributes of intermediate and/or definitive hosts, also may be important for predicting patterns of B. procyonis infection in intermediate hosts.


Asunto(s)
Infecciones por Ascaridida/veterinaria , Ascaridoidea/aislamiento & purificación , Ecosistema , Peromyscus/parasitología , Enfermedades de los Roedores/parasitología , Agricultura , Animales , Infecciones por Ascaridida/epidemiología , Infecciones por Ascaridida/transmisión , Vectores de Enfermedades , Indiana/epidemiología , Prevalencia , Mapaches , Enfermedades de los Roedores/epidemiología , Enfermedades de los Roedores/transmisión , Estadística como Asunto
11.
J Perinatol ; 31(7): 500-3, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21252963

RESUMEN

OBJECTIVE: To measure systemic haptoglobin (HPT) concentrations from birth in preterm (PT) and T newborns. To compare HPT in newborns without hemolysis or infection with values in bacteremic newborns. STUDY DESIGN: HPT was measured using enzyme-linked immunosorbent assay in 30 PT and 28 T newborns without hemolysis or infection at birth (cord blood), on days of life 2 to 4, and at 1 to 2 weeks of life. Concentrations were measured in eight additional newborns with bacteremia. Wilcoxon-Mann-Whitney test was used for comparisons. RESULT: HPT concentrations were consistently measurable from birth in PT and T neonates. Values were significantly greater in 2- to 4-day-old PT and T newborns than in newborns at birth (P<0.01). Bacteremic newborns had higher HPT concentrations than newborns without infection (P=0.033). CONCLUSION: HPT is detectable from birth in PT and T newborns. HPT concentrations increase in bacteremic newborns. HPT levels may have clinical utility in the evaluation of neonatal sepsis.


Asunto(s)
Bacteriemia/sangre , Haptoglobinas/análisis , Recien Nacido Prematuro/sangre , Nacimiento a Término/sangre , Bacteriemia/diagnóstico , Bacteriemia/epidemiología , Biomarcadores/sangre , Estudios de Cohortes , Susceptibilidad a Enfermedades/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Masculino , Estudios Prospectivos , Valores de Referencia , Medición de Riesgo , Sensibilidad y Especificidad
12.
Heredity (Edinb) ; 106(2): 253-60, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20606689

RESUMEN

Population genetics is increasingly being used to study the biology of parasites at the scales of both the host (infrapopulation, IP) and host population (component population, CP). In this study we tested three mechanistic hypotheses that could explain deviations from Hardy-Weinberg equilibrium (HWE) expectations due to heterozygote deficits (HDs) at the CP scale in raccoon ticks (Ixodes texanus; n=718) collected from raccoons (Procyon lotor; n=91) and genotyped at 11 microsatellite loci. These hypotheses were presence of technical issues (for example, null alleles), hierarchical structure (for example, host demography) and cryptic structure (for example, kin structure). Although statistical support for null alleles existed, their presence would also be expected to lead to an underestimation in levels of relatedness, and thus kin structure. However, we found the opposite pattern: significant HD at the IP scale being more likely in CPs with significant vs non-significant levels of kin structure. Our analyses revealed that pooling of kin groups could lead to highly variable levels of F(IS) among loci, a pattern usually suggestive of null alleles. We used Monte-Carlo (MC) simulations to show that the existence of subdivided breeding groups and high variance in individual reproductive success could adequately explain deviations from HWE in I. texanus. Thus, our results indicate that biological factors can lead to patterns that have usually been interpreted as technical issues (for example, null alleles), and that it is important to take such factors into consideration because loci deviating from HWE likely reflect the effects of real biological processes.


Asunto(s)
Ixodes/genética , Mapaches/parasitología , Animales , Femenino , Variación Genética , Hemicigoto , Heterocigoto , Masculino , Repeticiones de Microsatélite , Método de Montecarlo
13.
Int J Parasitol ; 40(7): 787-95, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20060394

RESUMEN

The American dog tick (Dermacentor variabilis) is an important vector of numerous pathogens of humans and animals. In this study, we analysed population genetic patterns in D. variabilis at scales of the host individual (infrapopulation) and population (component population) to elucidate fine-scale spatial and temporal factors influencing transmission dynamics. We genotyped D. variabilis collected from raccoons (Procyon lotor) trapped in two habitat patches (located in Indiana, USA) which were spatially proximate (5.9 km) and limited in size (10.48 Ha and 25.47 Ha, respectively). Despite the fine spatial sampling scale, our analyses revealed significant genetic differentiation amongst component populations and infrapopulations (within each component population), indicating a non-random pattern of encountering tick genotypes by raccoons at both scales evaluated. We found evidence for male-biased dispersal in the ticks themselves (in one component population) and an age-bias in spatial scales at which raccoons encountered ticks in the environment. At the scale of the component population, our analyses revealed that raccoons encountered ticks from a limited number of D. variabilis family groups, likely due to high reproductive variance amongst individual ticks. Finally, we found evidence for a temporal effect with raccoons encountering ticks in the environment as "clumps" of related individuals. While the genetic structure of parasite populations are increasingly being investigated at small spatial scales (e.g. the infrapopulation), our data reveal that genetic structuring can originate at scales below that of the infrapopulation, due to the interaction between temporal and biological factors affecting the encounter of parasites by individual hosts. Ultimately, our data indicate that genetic structure in parasites must be viewed as a consequence of both spatial and temporal variance in host-parasite interactions, which in turn are driven by demographic factors related to both the host and parasite.


Asunto(s)
Dermacentor/clasificación , Dermacentor/genética , Mapaches/parasitología , Infestaciones por Garrapatas/veterinaria , Factores de Edad , Animales , Femenino , Genotipo , Geografía , Indiana , Masculino , Repeticiones de Microsatélite , Reacción en Cadena de la Polimerasa , Factores Sexuales , Infestaciones por Garrapatas/parasitología , Infestaciones por Garrapatas/transmisión , Factores de Tiempo
14.
Plant Dis ; 94(7): 898-904, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30743550

RESUMEN

Field experiments were conducted at Gainesville and Marianna, FL in 2004 and 2005 in which severity of spotted wilt, caused by Tomato spotted wilt virus, and pod yield were compared in six peanut (Arachis hypogaea) cultivars. The six cultivars included the moderately field resistant cultivars ANorden, C-99R, and Georgia Green; the highly field resistant cultivars AP-3 and DP-1; and the susceptible cultivar SunOleic 97R. There were four trials at each location, with four planting dates that ranged from late March to early June. Tomato spotted wilt severity in moderately resistant and susceptible cultivars was lower at Gainesville than at Marianna in both years in moderately resistant and susceptible cultivars. Trends in incidence for the two locations were less evident for AP-3 and DP-1. At Gainesville, there were few differences in tomato spotted wilt severity, and severity ratings were similar for Georgia Green and SunOleic 97R in two of four trials in 2004 and across all trials in 2005. At Marianna, severity ratings were lower for Georgia Green than for SunOleic 97R in six of the eight trials, and severity of tomato spotted wilt was lower for AP-3, C-99R, and DP-1 than for Georgia Green in all eight trials. In 2004, there was a trend toward decreasing severity ratings for Georgia Green and SunOleic 97R with later planting dates, but not for AP-3 or DP-1 at Marianna. Split-plot field experiments were also conducted at Tifton, GA in 2005 through 2007 in which incidence of tomato spotted wilt and pod yield were compared for peanut cultivars AP-3 and Georgia Green across planting dates ranging from late April through late May. Incidence of tomato spotted wilt was lower for AP-3 than for Georgia Green within each planting date of all years, and planting date effects were smaller in AP-3, if observed at all, than in Georgia Green. In most planting dates of all three trials, yields were higher for AP-3 than for Georgia Green. The relationships between yield and planting date were not consistent. These results indicate that the level of field resistance in AP-3 and DP-1 cultivars is sufficient to allow planting in late April without greatly increasing the risk of losses to tomato spotted wilt.

15.
Bioinformatics ; 25(20): 2723-9, 2009 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-19620100

RESUMEN

MOTIVATION: Different mathematical methods have emerged in the post-genomic era to determine metabolic pathways. These methods can be divided into stoichiometric methods and path finding methods. In this paper we detail a novel optimization model, based upon integer linear programming, to determine metabolic pathways. Our model links reaction stoichiometry with path finding in a single approach. We test the ability of our model to determine 40 annotated Escherichia coli metabolic pathways. We show that our model is able to determine 36 of these 40 pathways in a computationally effective manner.


Asunto(s)
Biología Computacional/métodos , Escherichia coli/metabolismo , Redes y Vías Metabólicas , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Genoma Bacteriano
16.
Phytopathology ; 98(10): 1066-74, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18943452

RESUMEN

Tomato spotted wilt virus (TSWV), a member of the genus Tospovirus (family Bunyaviridae), is an important plant virus that causes severe damage to peanut (Arachis hypogaea) in the southeastern United States. Disease severity has been extremely variable in individual fields in Georgia, due to several factors including variability in weather patterns. A TSWV risk index has been developed by the University of Georgia to aid peanut growers with the assessment and avoidance of high risk situations. This study was conducted to examine the relationship between weather parameters and spotted wilt severity in peanut, and to develop a predictive model that integrates localized weather information into the risk index. On-farm survey data collected during 1999, 2002, 2004, and 2005 growing seasons, and derived weather variables during the same years were analyzed using nonlinear and multiple regression analyses. Meteorological data were obtained from the Georgia Automated Environmental Monitoring Network. The best model explained 61% of the variation in spotted wilt severity (square root transformed) as a function of the interactions between the TSWV risk index, the average daily temperature in April (TavA), the average daily minimum temperature between March and April (TminMA), the accumulated rainfall in March (RainfallM), the accumulated rainfall in April (RainfallA), the number of rain days in April (RainDayA), evapotranspiration in April (EVTA), and the number of days from 1 January to the planting date (JulianDay). Integrating this weather-based model with the TSWV risk index may help peanut growers more effectively manage tomato spotted wilt disease.


Asunto(s)
Enfermedades de las Plantas/estadística & datos numéricos , Enfermedades de las Plantas/virología , Solanum lycopersicum/virología , Tospovirus/patogenicidad , Clima , Monitoreo del Ambiente , Georgia , Meteoroides , Medición de Riesgo , Temperatura
17.
Avian Dis ; 49(4): 551-7, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16404998

RESUMEN

The pathogenesis of L. monocytogenes strain Scott A was studied by challenging day-old male turkey poults by air sac inoculation with tryptose phosphate broth containing 10(0) cfu (control), 10(4), 10(5), and 10(6) cfu (low challenge), or 10(7) and 10(8) cfu (high challenge) of the Scott A (serotype 4b) strain of L. monocytogenes. Mortality at 2 wk postinfection (PI) ranged from 25% for low challenge to 100% for high challenge (P= 0.0001). Gross and histopathological lesions were observed in heart, liver, spleen, lung, and bursa of Fabricius of mortalities at 4 days PI. Listeria monocytogenes challenge resulted in significantly decreased relative weight of the bursa of Fabricius and increased relative weight of the spleen, and L. monocytogenes was isolated by direct plating of liver, pericardium, brain, and both left and right stifle joint synovium (knee) cultures, as well as gall bladder, yolk sac, and cecal tonsil from transfer swabs onto Listeria-selective agar. Isolates were confirmed as positive using Gram stain, biochemical tests, and the Biolog system. High challenge resulted in confirmed L. monocytogenes isolation from 48% of left knee and 59% of right knee cultures. Low challenge resulted in isolation of L. monocytogenes from 11% of both left and right knee cultures. These results suggest that L. monocytogenes Scott A colonization of turkey knee synovial tissue can initiate in day-of-age poults and that L. monocytogenes Scott A can be invasive through air sac infection.


Asunto(s)
Listeria monocytogenes/patogenicidad , Listeriosis/veterinaria , Enfermedades de las Aves de Corral/microbiología , Infecciones del Sistema Respiratorio/veterinaria , Pavos/microbiología , Animales , Bolsa de Fabricio/patología , Listeria monocytogenes/clasificación , Listeria monocytogenes/aislamiento & purificación , Listeriosis/microbiología , Listeriosis/patología , Hígado/patología , Masculino , Miocardio/patología , Enfermedades de las Aves de Corral/patología , Infecciones del Sistema Respiratorio/microbiología , Infecciones del Sistema Respiratorio/patología
18.
Neural Netw ; 16(10): 1499-525, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14622879

RESUMEN

In this paper we consider the Euclidean Travelling Salesman Problem (ETSP). This is the problem of finding the shortest tour around a number of cities where the cities correspond to points in the Euclidean plane and the distances between cities are given by the usual Euclidean distance metric. We present a review of the literature with respect to neural network (NN) approaches for the ETSP, and the computational results that have been reported. Based upon this review we highlight two areas that are, in our judgement, currently neglected/lacking in the literature. These are: failure to make significant use of publicly available ETSP test problems in computational work, failure to address co-operation between neurons. Drawing upon our literature survey this paper presents a new Self-Organising NN approach, called the Co-Adaptive Net, which involves not just unsupervised learning to train neurons, but also allows neurons to co-operate and compete amongst themselves depending on their situation. Our Co-Adaptive Net algorithm also includes a number of algorithmic mechanisms that, based upon our literature review, we consider to have contributed to the computational success of previous algorithms. Results for 91 publicly available standard ETSP's are presented in this paper. The largest of these problems involves 85,900 cities. This paper presents: the most extensive computational evaluation of any NN approach on publicly available ETSP test problems that has been made to date in the literature, a NN approach that performs better, with respect to solution quality and/or computation time, than other NN approaches given previously in the literature. Drawing upon computational results produced as a result of the DIMACS TSP Challenge, we highlight the fact that none of the current NN approaches for the ETSP can compete with state of the art Operations Research heuristics. We discuss why we consider continuing to study and develop NN approaches for the ETSP to be of value.


Asunto(s)
Redes Neurales de la Computación , Solución de Problemas , Desempeño Psicomotor , Programas Informáticos , Algoritmos , Inteligencia Artificial , Humanos , Aprendizaje , Neuronas/fisiología , Reproducibilidad de los Resultados , Enseñanza , Factores de Tiempo
19.
AMIA Annu Symp Proc ; : 1056, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14728559

RESUMEN

The Mouse Models of Human Cancers Consortium (MMHCC) is a collaborative program designed to derive and characterize mouse models of human malignancies. To enhance information and resource exchange among the MMHCC investigators and other cancer research scientists, the NCI Center for Bioinformatics (NCICB, http://ncicb.nci.nih.gov/) has developed web-based resources that are freely available to the cancer research community. These resources include a website (http://emice.nci.nih.gov) and databases for cancer models (http://cancermodels.nci.nih.gov) and cancer images (http://cancerimages.nci.nih.gov).


Asunto(s)
Modelos Animales de Enfermedad , Internet , Ratones , Neoplasias , Animales , Bases de Datos como Asunto , Humanos
20.
J Fam Pract ; 50(11): 977, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11711016

RESUMEN

OBJECTIVE: Practice-based research is one method for answering questions about common problems that are seen infrequently in referral centers. We explored the potential limitations of this method. STUDY DESIGN: This was a prospective observational cohort study of participants in a practice-based research network who submitted data on 231 patients with dyspepsia from a total of 45,337 patient encounters over a 53-week period. Reporting of individual cases involved use of a relatively high-burden data instrument. Outcome measures were compared using rank correlation. POPULATION: We included 18 physicians in a Wisconsin research network study on initial management of dyspepsia in primary care settings. OUTCOMES MEASURED: The outcomes we measured were the rate of dyspepsia visits, average weekly patient volume, and self-reported compliance to the study protocol for each physician. RESULTS: A significant negative correlation existed between physician patient volume and the reported rate of dyspepsia visits. Self?reported compliance with the protocol was negatively correlated to patient volume and positively correlated to the reported rate of dyspepsia visits. CONCLUSIONS: Practice volume may influence the results in practice-based research. Investigators using practice-base research networks need to consider the complexity of their protocols and should be cognizant of compliance-sensitive measures.


Asunto(s)
Actitud del Personal de Salud , Recolección de Datos/estadística & datos numéricos , Recolección de Datos/normas , Dispepsia/tratamiento farmacológico , Medicina Familiar y Comunitaria/organización & administración , Investigación sobre Servicios de Salud/organización & administración , Médicos de Familia/psicología , Atención Primaria de Salud/organización & administración , Carga de Trabajo , Utilización de Medicamentos , Dispepsia/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Motivación , Evaluación de Resultado en la Atención de Salud , Estudios Prospectivos , Encuestas y Cuestionarios , Wisconsin/epidemiología
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