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1.
J Econ Entomol ; 110(2): 607-614, 2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28073978

RESUMEN

Since 2003, rootworm-protected transgenic corn has been commercially deployed in the United States as a principal method of control of western corn rootworm, Diabrotica virgifera virgifera LeConte. Durability of this technology depends partly on larval mortality ("dose") exerted by the traits, but density-dependent mortality can confound calculations of dose. Research reported here examined the effects of density-dependent mortality on adult emergence and estimates of trait dose. At sites in Illinois and Indiana, western corn rootworm eggs were infested at four densities on non-Bt corn and at a single density on corn hybrids with transgenic events MON 88017 (VT Triple PRO), DAS-59122-7 (Herculex Insect Protection), and MON 88017 × DAS-59122-7 (SmartStax corn). Beetles were collected weekly in large emergence cages. Density-dependent mortality and the effect of Bt traits were examined using percent survival from egg to adult, sex ratio, and beetle mass. Beetle emergence from Bt treatments was very low, and percent survival from non-Bt treatments was greatest at the lowest egg density (410 eggs per row-meter). Therefore, emergence from the lowest infestation density on non-Bt corn was used to estimate the effective dose of the Bt treatments. Sex ratio and beetle mass were unaffected by density-dependent effects and were not consistently affected by Bt traits. Dose was estimated at 97.4-99.3% for MON 88017, 98.8-99.9% for DAS-59122-7, and 99.7-100.0% for MON 88017 × DAS-59122-7. This study confirms the need to account for density-dependent mortality when estimating dose of corn rootworm protection events even at relatively low egg infestation densities.


Asunto(s)
Bacillus thuringiensis/genética , Escarabajos/fisiología , Protección de Cultivos/métodos , Zea mays/genética , Animales , Escarabajos/efectos de los fármacos , Endotoxinas/genética , Endotoxinas/farmacología , Indiana , Óvulo , Control Biológico de Vectores/métodos , Plantas Modificadas Genéticamente
2.
J Econ Entomol ; 107(1): 403-9, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24665726

RESUMEN

Commercial field corn (Zea mays L.) hybrids transformed to express some or all of the lepidopteran insect-resistant traits present in SmartStax corn hybrids were evaluated for insecticidal efficacy against a wide range oflepidopteran corn pests common to the northern United States, during 2008 to 2011 at locations in 15 states. SmartStax hybrids contain a pyramid of two Bacillus thuringiensis (Bt) derived events for lepidopteran control: event TC1507 expressing Cry1F protein and MON 89034 expressing CrylA.105 + Cry2Ab2. These studies focused on characterization of the relative efficacy of each event when expressed alone or in combination, and compared with non-Bt hybrid. Corn hybrids containing pyramided insecticidal proteins Cry1F + Cry1A.105 + Cry2Ab2 (SmartStax) consistently showed reduced plant feeding damage by a wide range of lepidopteran larvae compared with single event and non-Bt hybrids. Corn hybrids expressing TC1507 or MON 89034 as single or pyramided events were consistently efficacious against Ostrinia nubilalis (Hübner). SmartStax hybrids had less injury from Agrotis ipsilon (Hufnagel) and Striacosta albicosta (Smith) than corn hybrids containing only event MON 89034 but were not more efficacious than single event TC1507 hybrids. Corn hybrids with event MON 89034 provided better control of Helicoverpa zea (Boddie), than event TC1507 alone. Spodoptera frugiperda (J.E. Smith) efficacy was higher for hybrids with pyramid events and single events compared with the non-Bt hybrids. The spectra of activity of events TC1507 and MON 89034 differed. The combination of TC1507 + MON 89034 provided redundant control of some pests where the spectra overlapped and thereby are expected to confer a resistance management benefit.


Asunto(s)
Proteínas Bacterianas , Endotoxinas , Proteínas Hemolisinas , Insecticidas , Lepidópteros , Plantas Modificadas Genéticamente , Zea mays , Animales , Toxinas de Bacillus thuringiensis , Estados Unidos
3.
J Econ Entomol ; 106(2): 823-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23786070

RESUMEN

Studies were conducted across nine U.S. states, over 5 yr, to characterize the efficacy of transgenic corn (Zea mays L.) hybrids producing insecticidal proteins derived from Bacillus thuringiensis (Bt) for control of western corn rootworm, Diabrotica virgifera virgifera Le Conte. Hybrids tested had the same genetic background, contained one of two single events (DAS-59122-7 expressing Cry34Ab1/Cry35Ab1 or MON 88017 expressing Cry3Bb1) or a pyramid consisting of both rootworm-active events (SmartStax traits) and were compared with a non-Bt near isoline. Frequency analyses of root feeding data showed that hybrids containing both events sustained less root damage (0-3 node injury scale) than hybrids containing either event alone. The levels of root protection provided by MON 88017 and DAS-59122-7 were not different from each other. Efficacy was also evaluated based on consistency of protection, based on the proportion of plants with root ratings of either < or = 0.25 or < 1.00 on the node injury scale. The combination of two modes of action in SmartStax provided greater product consistency over a single mode of action at the 0.25 level and all hybrids producing Bt proteins provided equally high consistency at the 1.00 level. Overall these data show single and multiple mode of action hybrids provided high, consistent protection over the past 5 yr across the trial geography; however, pyramiding the rootworm Bt events provided greater and more consistent root protection. These findings also support that pyramided traits like SmartStax (Cry3Bb1 + Cry34Ab1/Cry35Ab1) remain a viable strategy for delaying resistance to either trait.


Asunto(s)
Bacillus thuringiensis/genética , Proteínas Bacterianas/genética , Escarabajos/efectos de los fármacos , Endotoxinas/genética , Proteínas Hemolisinas/genética , Zea mays/genética , Animales , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/metabolismo , Escarabajos/fisiología , Endotoxinas/metabolismo , Conducta Alimentaria , Proteínas Hemolisinas/metabolismo , Larva/efectos de los fármacos , Larva/fisiología , Control Biológico de Vectores , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Estados Unidos , Zea mays/crecimiento & desarrollo
4.
J Econ Entomol ; 105(5): 1825-34, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23156183

RESUMEN

Studies were conducted across the southern United States to characterize the efficacy of multiple Bacillus thuringiensis (Bt) events in a field corn, Zea mays L., hybrid for control of common lepidopteran and coleopteran pests. Cry1F protein in event TC1507 and Cry1A.105 + Cry2Ab2 proteins in event MON 89034 were evaluated against pests infesting corn on above-ground plant tissue including foliage, stalks, and ears. Cry34Ab1/Cry35Ab1 proteins in event DAS-59122-7 and Cry3Bb1 in event MON 88017 were evaluated against the larvae of Mexican corn rootworm, Diabrotica virgifera zeae Krysan and Smith, which occur below-ground. Field corn hybrids containing Cry1F, Cry1A.105 + Cry2Ab2, Cry34Ab1/Cry35Ab1, and Cry3Bb1 insecticidal proteins (SmartStax) consistently demonstrated reductions in plant injury and/or reduced larval survivorship as compared with a non-Bt field corn hybrid. Efficacy provided by a field corn hybrid with multiple Bt proteins was statistically equal to or significantly better than corn hybrids containing a single event active against target pests. Single event field corn hybrids provided very high levels of control of southwestern corn borer, Diatraea grandiosella (Dyar), lesser cornstalk borer, Elasmopalpus lignosellus (Zeller), and fall armyworm, Spodoptera frugiperda (J.E. Smith), and were not significantly different than field corn hybrids with multiple events. Significant increases in efficacy were observed for a field corn hybrid with multiple Bt events for sugarcane borer, Diatraea saccharalis (F.), beet armyworm, Spodoptera exigua (Hübner), corn earworm, Helicoverpa zea (Boddie), and Mexican corn rootworm. Utilization of field corn hybrids containing multiple Bt events provides a means for managing insect resistance to Bt proteins and reduces non-Bt corn refuge requirements.


Asunto(s)
Bacillus thuringiensis/genética , Proteínas Bacterianas/genética , Escarabajos/efectos de los fármacos , Endotoxinas/genética , Proteínas Hemolisinas/genética , Mariposas Nocturnas/efectos de los fármacos , Zea mays/genética , Animales , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/metabolismo , Escarabajos/fisiología , Endotoxinas/metabolismo , Conducta Alimentaria , Proteínas Hemolisinas/metabolismo , Larva/efectos de los fármacos , Larva/fisiología , Mariposas Nocturnas/fisiología , Control Biológico de Vectores , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Tallos de la Planta/genética , Tallos de la Planta/crecimiento & desarrollo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Semillas/genética , Semillas/crecimiento & desarrollo , Sudeste de Estados Unidos , Especificidad de la Especie , Spodoptera/efectos de los fármacos , Spodoptera/fisiología , Tennessee , Texas , Zea mays/crecimiento & desarrollo
5.
Environ Monit Assess ; 72(1): 95-114, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11693556

RESUMEN

The purpose of this study was to investigate the occurrence of high levels of pesticides in groundwater and rainwater in The Province of Limburg in The Netherlands. In groundwater samples in particular the presence of triazines--atrazine, simazine and propazine--was observed; besides these pesticides, dieldrin has also been observed. Atrazine and simazine were found to exceed the groundwater standard of 100 ng L(-1). In the rainwater samples, the presence of 13 of 23 different analyzed pesticides was observed. A number of pesticides were found in high concentrations; e.g. atrazine (>200 ng L(-1)). Two pesticides detected in rainwater (beta+gamma-HCH and atrazine) were found to exceed the groundwater standard. Seven pesticides in rainwater were found to exceed the target value and three pesticides the maximum tolerable risk value (DDT, heptachlor and heptachlorepoxide A), which are used as ecotoxicological standards in The Netherlands. Nitrate in 15 of 16 analyzed natural springs was found to exceed the guideline value for nitrate in drinking water of 50 mg L(-1), up to levels of about 200 mg L(-1). Nitrate concentrations in rainwater samples were observed up to 4.5 mg L(-1). A risk analysis of exposure to high pesticide levels in groundwater or rainwater has been performed using the model HESP. For atrazine levels due to deposition of rainwater in two different locations, exceedance of the T.D.I. level of 0.5 microg kg(-1) day(-1) based on WHO criteria was observed for children using both an urban and a rural scenario and use of groundwater as drinking water.


Asunto(s)
Nitratos/análisis , Plaguicidas/análisis , Contaminantes del Suelo/análisis , Abastecimiento de Agua , Monitoreo del Ambiente , Países Bajos , Lluvia , Valores de Referencia , Medición de Riesgo
6.
Optometry ; 71(4): 226-32, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10974921

RESUMEN

BACKGROUND: In keeping with current expectations in the health care community, the purpose of the American Board of Optometric Practice (ABOP) is to enhance the quality of optometric care available to the public by fostering continued competence for practitioners through administering education and examinations for certification and re-certification. The formation of ABOP makes possible for the first time a board certification process for optometrists. METHODS: The optometry model for board certification and recertification emphasizes the breadth of the profession. ABOP certification will be accomplished through a combination of examinations and high-quality, tested Board Certified Continuing Education (BCCE). Specific requirements for practitioners at various stages of their careers are presented. RESULTS: Board certification provides one important mechanism for an optometrist to demonstrate commitment to quality, professionalism, and ongoing clinical competence. The optometrist benefits from high-quality continuing education designed for timeliness, importance, and breadth. The public benefits by the enhancement of continued competence within the optometric profession. Health care agencies benefit by being able to recognize providers who have elected to demonstrate their qualifications through certification. CONCLUSIONS: Through board certification, optometrists will be able to demonstrate their commitment to maintaining clinical competence through a nationally uniform program, and they will be able to comply with standards that are generally recognized and required throughout the health care community.


Asunto(s)
Certificación/organización & administración , Optometría/organización & administración , Consejos de Especialidades/organización & administración , Educación Continua , Humanos , Optometría/educación , Estados Unidos
7.
Am J Health Promot ; 11(4): 264-71, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-10165520

RESUMEN

PURPOSE: This research investigated the effects of individual characteristics on cardiovascular reactivity, and in turn on the potential for developing coronary heart disease. DESIGN: Path analysis was performed using LISREL, a structural equation modeling program providing maximum likelihood estimators and goodness-of-fit measures. SETTING: Data were collected during a health assessment program, from participants attending a Department of Defense senior service school. SUBJECTS: Participants were 134 senior-ranking male military and civilian employee volunteers, representing approximately 84% of all students in training. MEASURES: Five individual characteristics, four measures of cardiovascular reactivity, and one coronary heart disease risk potential variable were investigated. These included Physical Fitness, Type A behavior, Trait Anger and Trait Anxiety, Diastolic and Systolic Blood Pressure measures, and Coronary Heart Disease Risk. RESULTS: Significant path coefficients (critical ratios > 2) indicated that the mean diastolic blood pressure under a video stress condition was predictive of increased potential of developing coronary heart disease (.51), while hard driving Type A behavior was a cardiovascular reactivity antecedent associated with an increase in coronary heart disease risk directly (.14) and indirectly (.39). Physical fitness, on the other hand, had a positive affect in that increased fitness was related to lower cardiovascular reactivity when participants were stressed (-.58). CONCLUSIONS: Physical fitness is indirectly beneficial in reducing coronary heart disease risk potential by reducing an individual's diastolic blood pressure response, while scoring high as a Type A Hard Driving personality increases cardiovascular reactivity and coronary heart disease risk. This study is limited to middle-aged males who were generally healthy and displayed concern for their health.


Asunto(s)
Sistema Cardiovascular/fisiopatología , Enfermedad Coronaria/etiología , Aptitud Física , Personalidad Tipo A , Adulto , Presión Sanguínea , Enfermedad Coronaria/fisiopatología , Diástole , Prueba de Esfuerzo , Humanos , Funciones de Verosimilitud , Masculino , Personal Militar , Factores de Riesgo
8.
ANNA J ; 23(1): 46-9, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8702361

RESUMEN

Epoetin alfa therapy has dramatically improved therapeutic responses and outcomes for anemic patients with end-stage renal disease. This article examines clinical evidence supporting the correlation between patient outcomes and a higher hematocrit and addresses some of the barriers that may hinder optimal patient outcomes.


Asunto(s)
Anemia/terapia , Eritropoyetina/uso terapéutico , Hematócrito , Fallo Renal Crónico/complicaciones , Actividades Cotidianas , Anemia/sangre , Anemia/etiología , Femenino , Humanos , Persona de Mediana Edad , Calidad de Vida
9.
J Anim Sci ; 72(6): 1467-74, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8071171

RESUMEN

Data of sixty finished, crossbred lambs were used to develop prediction equations of total weight of retail-ready cuts (SUM). These cuts were the leg, sirloin, loin, rack, shoulder, neck, riblets, shank, and lean trim (85/15). Measurements were taken on live lambs and on both hot and cold carcasses. A four-terminal bioelectrical impedance analyzer (BIA) was used to measure resistance (Rs, ohms) and reactance (Xc, ohms). Distances between detector terminals (L, centimeters) were recorded. Carcass temperatures (T, degrees C) at time of BIA readings were also recorded. The equation predicting SUM from cold carcass measurements (n = 53, R2 = .97) was .093 + .621 x weight-.0219 x Rs + .0248 x Xc + .182 x L-.338 x T. Resistance accounted for variability in SUM over and above weight and L (P = .0016). The above equation was used to rank cold carcasses in descending order of predicted SUM. An analogous ranking was obtained from a prediction equation that used weight only (R2 = .88). These rankings were divided into five categories: top 25%, middle 50%, bottom 25%, top 50%, and bottom 50%. Within-category differences in average fat cover, yield grade, and SUM as a percentage of cold carcass weight of carcasses not placed in the same category by both prediction equations were quantified with independent t-tests. These differences were statistically significant for all categories except middle 50%. This shows that BIA located those lambs that could more efficiently contribute to SUM because a higher portion of their weight was lean.


Asunto(s)
Composición Corporal , Peso Corporal , Impedancia Eléctrica , Carne , Ovinos/anatomía & histología , Mataderos , Animales
10.
AACN Clin Issues Crit Care Nurs ; 3(3): 605-13, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1524932

RESUMEN

Technologic advances provide renal replacement therapies to critically ill pediatric patients. Having multiplied rapidly, the options for intervention and treatment of acute renal failure in infants and small children are numerous. Thus, the need for the dialysis nurse and the critical care nurse to maintain, expand, and develop a new baseline of knowledge is a constant challenge. This article explores the management and treatment options for acute renal failure in infants and children.


Asunto(s)
Lesión Renal Aguda/terapia , Diálisis Renal/métodos , Lesión Renal Aguda/enfermería , Adolescente , Niño , Preescolar , Cuidados Críticos , Humanos , Diálisis Renal/instrumentación , Diálisis Renal/enfermería
11.
Am Rev Respir Dis ; 145(6): 1483-6, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1596022

RESUMEN

A 57-yr-old man with a chronic lung cavity presumed to be related to ankylosing spondylitis and/or old cavitary tuberculosis presented with hemoptysis and rapidly developed lower extremity paresis and hypoesthesia. On chest radiograph he had a left upper lobe lesion suggestive of aspergilloma combined with a large left empyema with bronchopleural fistula. Serologic analysis demonstrated precipitins and very high titer IgG antibodies to Aspergillus fumigatus antigens. Decompressive laminectomy from T1 to T5 was performed, with drainage of A. fumigatus culture-positive material from an epidural abscess compressing the spinal cord. Chest drainage was required for control of the empyema. With a total course of 3 g of intravenously administered amphotericin B, rehabilitative therapy, and chronic empyema drainage, he is now at home and ambulatory with assistance. He is also being followed by regular serum assays of IgG antibodies to Aspergillus proteins. We report the case of an apparent long-term survivor of a formerly lethal and/or nonreversible paraplegic condition. The critical factors compared with previous cases with a poor outcome would appear to be prompt neurosurgical intervention, restoration of a normal number of T-cells, effective long-term chest drainage, and high dose amphotericin treatment.


Asunto(s)
Absceso/microbiología , Anfotericina B/uso terapéutico , Aspergilosis/complicaciones , Aspergillus fumigatus/aislamiento & purificación , Empiema Pleural/microbiología , Enfermedades Pulmonares Fúngicas/complicaciones , Compresión de la Médula Espinal/etiología , Aspergilosis/tratamiento farmacológico , Espacio Epidural , Humanos , Enfermedades Pulmonares Fúngicas/tratamiento farmacológico , Masculino , Persona de Mediana Edad
13.
Psychol Rep ; 65(3 Pt 2): 1136-8, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2623104

RESUMEN

Results indicated that job stress is affected by physical stressors, role conflict, quantitative workload, job boredom, and whether one has an external locus of control. Coronary artery disease potential, as measured by the cholesterol ratio, was affected by sex, height-weight index, and smoking.


Asunto(s)
Enfermedad Coronaria/psicología , Satisfacción en el Trabajo , Enfermedades Profesionales/psicología , Estrés Psicológico/complicaciones , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas de Personalidad , Factores de Riesgo
15.
Dent Clin North Am ; 30(4 Suppl): S1-10, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3465633

RESUMEN

This article presented a new dental stress model, which is based upon "perceived" (psychological) stresses. The model consists of antecedents of stress (stressors) and the resulting job and life stresses which produce psychologic and physiologic stress responses and behavioral consequences. From the proposed model, a stress evaluation questionnaire was constructed to help dental personnel diagnose excessive stressors in their own lifestyles.


Asunto(s)
Odontólogos , Enfermedades Profesionales/psicología , Estrés Psicológico/diagnóstico , Odontólogos/psicología , Humanos , Estilo de Vida , Modelos Psicológicos , Enfermedades Profesionales/diagnóstico , Estrés Fisiológico/diagnóstico , Encuestas y Cuestionarios
16.
Aviat Space Environ Med ; 56(7): 654-9, 1985 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-4026748

RESUMEN

Research to predict stress, organizational effectiveness, and potential for developing coronary heart disease (CHD) is presented based on two samples (n = 357 and n = 225). Results indicate that perceived stress is predicted by a combination of individual and job related characteristics. The data suggest that stress, in turn, affects individual and organizational health and effectiveness, by causing increases in cold/flu episodes, somatic symptoms, while decreasing job satisfaction. In addition, stress has an indirect effect on job performance and absenteeism. Models for predicting the ratio of total serum cholesterol divided by HDL cholesterol as an indicator of coronary heart disease potential are provided and a CHD screening model is proposed.


Asunto(s)
Enfermedad Coronaria/etiología , Estrés Fisiológico/etiología , Absentismo , Adolescente , Adulto , Anciano , Colesterol/sangre , HDL-Colesterol/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Riesgo , Estrés Fisiológico/complicaciones
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