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1.
Cureus ; 13(10): e19069, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34849306

RESUMEN

Background and objective Healthcare-associated ventriculitis and meningitis (HAVM) is frequent in neurocritical patients and associated with significant mortality. Surgery and intracranial devices are usually necessary and may lead to infection. Classical clinical signs and cerebral spinal fluid (CSF) analysis may be unreliable. The purpose of this study was to characterize the prevalence of HAVM, risk factors, and interventions in the neurocritical population admitted in the ICU. Methods This was a retrospective single-center analysis of all adult neurocritical patients admitted to an ICU during a three-year period. Results A total of 218 neurocritical patients were included. The prevalence of HAVM was 13% and it was found to be associated with mortality. When suspected, it was not possible to exclude HAVM in 30% of the patients. HAVM was significantly associated with surgery, surgical reintervention, and brain devices. Sustained fever was the most frequent clinical sign, and it was significantly associated with unexcluded HAVM. CSF cell count was significantly higher in HAVM, though without microbiological isolation in most of the cases. Conclusion Brain damage, interventions, and devices may significantly alter cerebral homeostasis. Sustained fever is very frequent and may be attributed to several conditions. CSF cell count is useful for the diagnosis of HAVM. HAVM is a clinical challenge in the management of neurocritical patients with important therapeutic and prognostic implications.

2.
Front Immunol ; 11: 993, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32582156

RESUMEN

Objective: To evaluate the short term safety and potential therapeutic effect of allogenic adipose tissue-derived stromal/stem cells (ASCs) + cholecalciferol in patients with recent-onset T1D. Methods: Prospective, phase II, open trial, pilot study in which patients with recent onset T1D received ASCs (1 × 106 cells/kg) and cholecalciferol 2000 UI/day for 3 months (group 1) and were compared to controls with standard insulin therapy (group 2). Adverse events, C-peptide (CP), insulin dose, HbA1c, time in range (TIR), glucose variability (continuous glucose monitoring) and frequency of CD4+FoxP3+ T-cells (flow cytometry) were evaluated at baseline (T0) and after 3 months (T3). Results: 13 patients were included (8: group 1; 5: group 2). Their mean age and disease duration were 26.7 ± 6.1 years and 2.9 ± 1.05 months. Adverse events were transient headache (n = 8), mild local reactions (n = 7), tachycardia (n = 4), abdominal cramps (n = 1), thrombophlebitis (n = 4), mild floaters (n = 2), central retinal vein occlusion (n = 1, complete resolution). At T3, group 1 had lower insulin requirement (0.22 ± 0.17 vs. 0.61±0.26IU/Kg; p = 0.01) and HbA1c (6.47 ± 0.86 vs. 7.48 ± 0.52%; p = 0.03) than group 2. In group 1, 2 patients became insulin free (for 4 and 8 weeks) and all were in honeymoon at T3 (vs. none in group 2; p = 0.01). CP variations did not differ between groups (-4.6 ± 29.1% vs. +2.3 ± 59.65%; p = 0.83). Conclusions: Allogenic ASCs + cholecalciferol without immunosuppression was associated with stability of CP and unanticipated mild transient adverse events in patients with recent onset T1D. ClinicalTrials.gov registration: NCT03920397.


Asunto(s)
Tejido Adiposo/citología , Colecalciferol/uso terapéutico , Diabetes Mellitus Tipo 1/terapia , Suplementos Dietéticos , Trasplante de Células Madre Mesenquimatosas , Vitaminas/uso terapéutico , Adolescente , Adulto , Biomarcadores/sangre , Glucemia/metabolismo , Brasil , Colecalciferol/efectos adversos , Terapia Combinada , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/diagnóstico , Suplementos Dietéticos/efectos adversos , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Masculino , Trasplante de Células Madre Mesenquimatosas/efectos adversos , Proyectos Piloto , Estudios Prospectivos , Factores de Tiempo , Trasplante Homólogo , Resultado del Tratamiento , Vitaminas/efectos adversos , Adulto Joven
3.
Exp Appl Acarol ; 70(2): 165-77, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27495808

RESUMEN

The coconut production system, in which the coconut mite Aceria guerreronis is considered a key pest, provides an interesting model for integration of biological and chemical control. In Brazil, the most promising biological control agent for the coconut mite is the phytoseiid predator Neoseiulus baraki. However, acaricides are widely used to control the coconut mite, although they frequently produce unsatisfactory results. In this study, we evaluated the simultaneous direct effect of dry residue contact and contaminated prey ingestion of the main acaricides used on coconut palms (i.e., abamectin, azadirachtin and fenpyroximate) on life-history traits of N. baraki and their offspring. These acaricides are registered, recommended and widely used against A. guerreronis in Brazil, and they were tested at their label rates. The offspring of the exposed predators was also evaluated by estimating the instantaneous rate of population increase (r i ). Abamectin compromised female performance, whereas fenpyroximate did not affect the exposed females (F0). Nonetheless, fenpyroximate strongly compromised the offspring (F1) net reproductive rate (R0), intrinsic rate of population growth (r i ), and doubling time (DT). In contrast, fenpyroximate did not have such effects on the 2nd generation (F2) of predators with acaricide-exposed grandparents. Azadirachtin did not affect the predators, suggesting that this acaricide can be used in association with biological control by this predatory species. In contrast, the use of abamectin and fenpyroximate is likely to lead to adverse consequences in the biological control of A. guerreronis using N. baraki.


Asunto(s)
Acaricidas/toxicidad , Benzoatos/toxicidad , Ivermectina/análogos & derivados , Limoninas/toxicidad , Ácaros/efectos de los fármacos , Pirazoles/toxicidad , Animales , Brasil , Femenino , Ivermectina/toxicidad , Larva/efectos de los fármacos , Masculino , Ácaros/crecimiento & desarrollo , Ácaros/fisiología , Ninfa/efectos de los fármacos , Óvulo/efectos de los fármacos , Crecimiento Demográfico , Conducta Predatoria/efectos de los fármacos , Reproducción/efectos de los fármacos
4.
Exp Appl Acarol ; 69(3): 297-310, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27059867

RESUMEN

Reducing the losses caused by Aceria guerreronis Keifer has been an arduous task for farmers. However, there are no detailed studies on losses that simultaneously analyse correlated parameters, and very few studies that address the economic viability of chemical control, the main strategy for managing this pest. In this study the objectives were (1) to estimate the crop loss due to coconut mite and (2) to perform a financial analysis of acaricide application to control the pest. For this, the following parameters were evaluated: number and weight of fruits, liquid albumen volume, and market destination of plants with and without monthly abamectin spraying (three harvests). The costs involved in the chemical control of A. guerreronis were also quantified. Higher A. guerreronis incidence on plants resulted in a 60 % decrease in the mean number of fruits harvested per bunch and a 28 % decrease in liquid albumen volume. Mean fruit weight remained unaffected. The market destination of the harvested fruit was also affected by higher A. guerreronis incidence. Untreated plants, with higher A. guerreronis infestation intensity, produced a lower proportion of fruit intended for fresh market and higher proportions of non-marketable fruit and fruit intended for industrial processing. Despite the costs involved in controlling A. guerreronis, the difference between the profit from the treated site and the untreated site was 18,123.50 Brazilian Real; this value represents 69.1 % higher profit at the treated site.


Asunto(s)
Acaricidas , Agricultura/economía , Cocos/economía , Ivermectina/análogos & derivados , Ácaros , Control de Ácaros y Garrapatas , Animales , Brasil , Cocos/crecimiento & desarrollo , Frutas/economía , Frutas/crecimiento & desarrollo
5.
Opt Express ; 22(3): 3425-31, 2014 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-24663632

RESUMEN

We have experimentally demonstrated a reconfigurable silicon thermo-optical device able to tailor its intrinsic spectral optical response by means of the thermo-optical control of individual and uncoupled resonant modes of micro-ring resonators. Preliminarily results show that the device's optical response can be tailored to build up distinct and reconfigurable logic levels for optical signal processing, as well as control of overall figures of merit, such as free-spectral-range, extinction ratio and 3 dB bandwidth. In addition, the micro-heaters on top of the ring resonators are able to tune the resonant wavelength with efficiency of 0.25 nm/mW within a range of up to 10 nm, as well as able to switch the resonant wavelength within fall and rise time of 15 µs.

6.
Rev. bras. entomol ; 58(1): 71-76, Jan.-Mar. 2014. ilus
Artículo en Inglés | LILACS | ID: lil-707153

RESUMEN

Population growth and within-plant distribution of the striped mealybug Ferrisia virgata (Cockerell) (Hemiptera, Pseudococcidae) on cotton. The striped mealybug, Ferrisia virgata (Cockerell) (Hemiptera, Pseudococcidae), is a widely distributed and polyphagous pest species, which naturally occurs on cotton plants in Brazil. This study evaluated the establishment and population growth as well as the within-plant distribution of F. virgata on four cotton cultivars: CNPA 7H (white fibers), BRS Verde, BRS Safira, and BRS Rubi (colored fibers). The experiment was conducted in a complete randomized design with four treatments (cultivars) and 18 replications of each. Thus, cotton plants of each cultivar were infested with 100 newly hatched nymphs of F. virgata. The number of adult female mealybugs and the total number of mealybugs per plant were quantified, respectively, at 25 and 50 days after infestation. The developmental and pre-reproductive periods were also determined. Furthermore, we verified the distribution of F. virgata on the plant parts at 25 and 50 days after infestation. Ferrisia virgata showed similar growth of 412-fold in the four cotton cultivars studied. Also, the nymphs were spread on infested leaves; the secondgeneration nymphs were spread and established in all plant parts. Our results characterize F. virgata as having much potential as an important cotton pest in Brazil.

7.
J Trop Pediatr ; 60(1): 40-6, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23963460

RESUMEN

OBJECTIVE: Assess drinking water fortification with iron and/or ascorbic acid as a strategy to control iron-deficiency anemia and iron deficiency. METHODS: Randomized blind clinical study, fortifying drinking water to 153 pre-school children during 3 months, with iron and ascorbic acid (A), ascorbic acid (B) or plain water (C). Hemoglobin (Hb), mean corpuscular volume (MCV) and ferritin were measured. RESULTS: Within the groups, Hb raised in all three groups, MCV in A and B and ferritin in A. The difference between time points 0 and 1 was significant between A and B for Hb, when A and B were compared with C for MCV and when A was compared with either B or C for ferritin. CONCLUSIONS: Water fortification is efficient in controlling iron deficiency and anemia. Iron stores' recovery depends on a more effective offer of iron. Water fortification must be preceded by a careful assessment of the previous nutritional status.


Asunto(s)
Anemia Ferropénica/prevención & control , Ácido Ascórbico/administración & dosificación , Guarderías Infantiles , Agua Potable , Alimentos Fortificados , Hemoglobinas/análisis , Hierro/administración & dosificación , Anemia Ferropénica/epidemiología , Brasil/epidemiología , Preescolar , Método Doble Ciego , Femenino , Hemoglobinas/efectos de los fármacos , Humanos , Deficiencias de Hierro , Masculino , Evaluación Nutricional , Estado Nutricional , Prevalencia , Resultado del Tratamiento , Vitaminas/administración & dosificación
8.
Opt Express ; 21(3): 3861-71, 2013 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-23481842

RESUMEN

A proof-of-concept for a new and entirely CMOS compatible tunable nanobeam cavity is demonstrated in this paper. Preliminary results show that a compact nanobeam cavity (~20 µm(2)) with high Q-factor (~50,000) and integrated with a micro-heater atop, is able of tuning the resonant wavelength up to 15 nm with low power consumption (0.35nm/mW), and of attaining high modulation depth with only ~100 µW. Additionally, a tunable bi-stable behavior is reported.


Asunto(s)
Rayos Láser , Nanotecnología/instrumentación , Refractometría/instrumentación , Resonancia por Plasmón de Superficie/instrumentación , Cristalización , Suministros de Energía Eléctrica , Diseño de Equipo , Análisis de Falla de Equipo , Fotones , Integración de Sistemas
9.
Diabetes Res Clin Pract ; 99(3): e33-6, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23347689

RESUMEN

C peptide (CP) was evaluated in 88 individuals with type 1 diabetes, variable disease duration and multiethnic background. Initially, 28 patients had detectable CP, which persisted in 46.2% after 17.4±4 months. CP decline was associated with ethnicity, HbA1c and baseline CP, but not with GADA, PTPN22 or insulin gene polymorphisms.


Asunto(s)
Péptido C/metabolismo , Diabetes Mellitus Tipo 1/etnología , Diabetes Mellitus Tipo 1/metabolismo , Adolescente , Adulto , Edad de Inicio , Población Negra , Niño , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Insulina/genética , Masculino , Población Blanca
10.
Nat Mater ; 12(2): 108-13, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23178268

RESUMEN

Invisibility by metamaterials is of great interest, where optical properties are manipulated in the real permittivity-permeability plane. However, the most effective approach to achieving invisibility in various military applications is to absorb the electromagnetic waves emitted from radar to minimize the corresponding reflection and scattering, such that no signal gets bounced back. Here, we show the experimental realization of chip-scale unidirectional reflectionless optical metamaterials near the spontaneous parity-time symmetry phase transition point where reflection from one side is significantly suppressed. This is enabled by engineering the corresponding optical properties of the designed parity-time metamaterial in the complex dielectric permittivity plane. Numerical simulations and experimental verification consistently exhibit asymmetric reflection with high contrast ratios around a wavelength of of 1,550 nm. The demonstrated unidirectional phenomenon at the corresponding parity-time exceptional point on-a-chip confirms the feasibility of creating complicated on-chip parity-time metamaterials and optical devices based on their properties.

11.
Opt Express ; 20(13): 14722-33, 2012 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-22714533

RESUMEN

A proof-of-concept for a new and entirely CMOS compatible thermo-optic reconfigurable switch based on a coupled ring resonator structure is experimentally demonstrated in this paper. Preliminary results show that a single optical device is capable of combining several functionalities, such as tunable filtering, non-blocking switching and reconfigurability, in a single device with compact footprint (~50 µm x 30 µm).


Asunto(s)
Dispositivos Ópticos , Refractometría/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Termografía/instrumentación , Transductores , Diseño de Equipo , Análisis de Falla de Equipo
12.
Anemia ; 2011: 815194, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21826263

RESUMEN

Anemia and iron deficiency should receive special attention considering their high prevalence and serious consequences. For prevention, globally it is recommended to increase dietary iron intake, iron fortification of industrialized foods, and medical iron supplementation. Food fortification for the prevention of iron deficiency in developing countries should consider carriers locally available and consumed daily, requiring limited infrastructure and technology. Drinking water is the iron carrier we have been working for years for the prevention of iron deficiency and anemia in small children in Brazil. It was shown that studies with iron-fortified drinking water were proved to be effective on children's anemia prevention. Water is found everywhere, consumed daily by everyone may be easily fortified with simple technology, is low priced and was effective on the prevention of children's anemia. Fortification of drinking water with iron was locally implemented with the direct participation of the government and community. Government authorities, health personnel and population were part of the project and responsible for its community implementation. The mayor/municipality permitted and supported the proposal to supply it to children at their day-care centers. To keep the children drinking water iron fortified supply an officially authorized legislation was also approved.

13.
Artículo en Inglés | MEDLINE | ID: mdl-21459021

RESUMEN

OBJECTIVES: The objectives of this study were to evaluate pH, available chlorine content, and antibacterial activity of endodontic irrigants and their combinations. STUDY DESIGN: The pH and chlorine content of sodium hypochlorite (NaOCl) were analyzed pure and in combination with 10% citric acid (CA) and apple vinegar (AV). The antibacterial effect of the following solutions was measured by direct contact test against Enterococcus faecalis: 2.5% NaOCl, 2.5% NaOCl +10% CA (7:3), 2.5% NaOCl + AV (5:5), 10% CA, and AV. Sterile saline was used as control. The colony-forming units were determined by serial decimal dilutions. RESULTS: The combination of 2.5% NaOCl with CA or AV lowered the pH and the chlorine content. NaOCl, alone or in combination was able to eliminate E. faecalis in 30 seconds, and CA, after 10 minutes. AV promoted reduction (32.2%) after 10 minutes. CONCLUSIONS: NaOCl with acidic solutions lowered the pH and the chlorine content, but did not alter its antibacterial effect.


Asunto(s)
Antibacterianos/farmacología , Cloro/análisis , Enterococcus faecalis/efectos de los fármacos , Irrigantes del Conducto Radicular/farmacología , Hipoclorito de Sodio/farmacología , Ácido Acético/farmacología , Carga Bacteriana , Ácido Cítrico/farmacología , Humanos , Concentración de Iones de Hidrógeno , Ensayo de Materiales , Viabilidad Microbiana/efectos de los fármacos , Irrigantes del Conducto Radicular/análisis , Hipoclorito de Sodio/análisis , Espectrofotometría , Factores de Tiempo
14.
Phytochemistry ; 69(1): 168-75, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17709122

RESUMEN

Essential oils were obtained from roots of 10 Aristolochia species by hydrodistillation and analysed by GC-MS. A total of 75 compounds were identified in the analysed oils. Multivariate analyses of the chemical constituents of the roots enabled classification of the species into four morphological groups. These forms of analysis represent an aid in identification of further specimens belonging to these species.


Asunto(s)
Aristolochia/química , Aristolochia/clasificación , Cromatografía de Gases y Espectrometría de Masas , Aceites Volátiles/análisis , Aceites Volátiles/química , Raíces de Plantas/química , Análisis de Componente Principal
15.
Recurso de Internet en Español | LIS - Localizador de Información en Salud | ID: lis-14375

RESUMEN

Informaciones acerca de la obesidad infantil y sus factores genéticos, factores ambientales, el diagnóstico, complicaciones, tratamiento, dieta a ser adoptada y actividades físicas para el niño obeso. Trae graficos y tablas. Documento en formato PDF, requiere Acrobat Reader.


Asunto(s)
Obesidad , Niño , Salud Infantil
16.
Dent Mater ; 23(10): 1245-9, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17204320

RESUMEN

OBJECTIVE: To identify and quantify the camphorquinone (CQ) used in different brands of composite resins as a function of the shade analyzed. MATERIALS AND METHODS: Filtek Z250 A3 (FZA3), Filtek Z-250 Incisal (FZI), Pyramid Enamel A1 (PEA1), Pyramid Enamel Translucent (PET), Filtek Supreme A3E (FSA3) and Filtek Supreme GT (FSGT) were used. Five hundred milligrams of each resin were weighed and then dissolved in 1.0 ml of methanol. The samples were centrifuged to accelerate the sedimentation of the inorganic particles. 0.8 ml of the supernatant solution was collected with a pipette and assessed under gas chromatography coupled to the mass spectrometer (GC-MS). The results were compared to pure CQ solutions, used as a standard. Student's t-test, (p=0.05) significant at the level of 5%, compared the results of each brand shade. RESULTS: A smaller amount of camphorquinone was found in Filtek Z-250 (FZI) resin incisal shade when compared to (FZA3) A3 shade. On the other hand, Filtek Supreme resin featured a statistically larger camphorquinone amount in the incisal shade. In Pyramid Enamel resin camphorquinone was found only in shade A1, while the photoinitiator used in the Translucent shade was not identified. SIGNIFICANCE: Based on the data obtained, it is possible to conclude that a single composite resin brand may feature differences in amount and type of photoinitiator used.


Asunto(s)
Resinas Acrílicas/química , Color , Resinas Compuestas/química , Poliuretanos/química , Terpenos/análisis , Ensayo de Materiales
17.
J Pediatr (Rio J) ; 80(3): 229-34, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15192767

RESUMEN

OBJECTIVE: To examine the determining factors of anemia and iron deficiency in children attending two day care centers in the town of Pontal, southeast of Brazil. METHODS: Cross-sectional study was conducted in 192 children aged 12 to 72 months. Personal data (age, sex, use of medicinal iron supplements, duration of breast-feeding, type of delivery, prenatal care, weight, and height), and socioeconomic data (number of co-inhabitants, parental schooling, and per capita family income) were obtained and evaluated together with hemoglobin, serum transferrin receptor, ferritin, and iron deficiency anemia. RESULTS: Age was the variable that most affected iron nutritional status, with higher hemoglobin values, lower transferrin receptor concentrations, higher ferritin values and lower iron deficiency anemia being detected with increasing age. The other studied variables did not show any correlation with iron nutritional status. CONCLUSION: The obtained data suggest that control strategies for this preschool population should be especially directed at younger children.


Asunto(s)
Anemia Ferropénica/epidemiología , Deficiencias de Hierro , Pobreza , Anemia Ferropénica/etiología , Brasil/epidemiología , Niño , Preescolar , Ensayo de Inmunoadsorción Enzimática , Métodos Epidemiológicos , Femenino , Ferritinas/sangre , Hemoglobinas/análisis , Humanos , Masculino , Receptores de Transferrina/sangre , Factores Socioeconómicos
18.
J. pediatr. (Rio J.) ; 80(3): 229-234, maio-jun. 2004. tab
Artículo en Inglés | LILACS | ID: lil-362574

RESUMEN

OBJETIVO: Avaliar fatores determinantes de anemia e deficiência de ferro em crianças de duas creches da cidade de Pontal, sudeste do Brasil. MÉTODOS: Estudo transversal foi realizado avaliando-se 192 crianças com idades entre 12 e 72 meses. Dados pessoais (idade, sexo, uso de ferro medicamentoso, duração do aleitamento materno, tipo de parto, cuidados pré-natais, peso e estatura) e dados socioeconômicos (número de co-habitantes, escolaridade dos pais e renda per capita familiar) foram obtidos e correlacionados com hemoglobina, receptores de transferrina, ferritina e anemia ferropriva. RESULTADOS: A idade foi a variável mais afetada pelo estado nutricional de ferro, correlacionando-se com maiores valores de hemoglobina e ferritina e menores valores de receptor de transferrina, sendo que menos anemia ferropriva foi detectada quanto maior a idade. As outras variáveis estudadas não apresentaram correlação com o estado nutricional de ferro. CONCLUSAO: Os dados sugerem que as estratégias de controle para essa população de crianças pré-escolares devem ser direcionadas especialmente para aquelas de menor idade.


Asunto(s)
Humanos , Masculino , Femenino , Preescolar , Niño , Anemia Ferropénica/epidemiología , Hierro/deficiencia , Pobreza , Anemia Ferropénica/etiología , Brasil/epidemiología , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Ferritinas , Hemoglobinas/análisis , Modelos Logísticos , Prevalencia , Factores de Riesgo , Receptores de Transferrina/sangre , Factores Socioeconómicos , Estadísticas no Paramétricas
19.
Neotrop. entomol ; 31(1): 101-108, Jan.-Mar. 2002. graf, tab
Artículo en Portugués | LILACS | ID: lil-513753

RESUMEN

The occasional feeding on plants by Podisus nigrispinus (Dallas) has produced different responses on its biology according to the plant species available. This study was undertaken to determine the development and reproduction of P. nigrispinus when confined on Gossypium hirsutum cv. Precocious CNPA1 and processing tomato Lycopersicum esculentum cv. IPA5 plants, using Tenebrio molitor (L.) pupa as prey. Nymphs and adults of P. nigrispinus were provided with prey and plants of cotton, prey and plant of tomato, prey and water, and only the prey. The predator could access the plants by caging nymphs and prey on plant leaves cultivated in pots. Nymphs caged on cotton or tomato plants with prey showed shorter duration of second and fifth ínstars. However, the shortest development period was observed for nymphs caged on cotton plants with prey. Nymphs fed on prey alone had lower survival within each ínstar and for the whole stage when compared to nymphs accessing plant, prey and water. The availability of cotton plants to nymphs produced heavier individuals compared to tomato plants, prey and water, and only prey. The adult weight at emergence was similar between plants and prey plus water, and superior to the treatment with prey alone. However, females of P. nigrispinus with access to the prey and cotton plant and prey and water showed significant body weight increase at the beginning of the reproductive activity, while females confined on tomato plants and only on prey did not range their weight during their lives. The availability of cotton and tomato plants to P. nigrispinus increased the number of eggs produced and adult longevity; moreover the former plant promoted higher oviposition frequency. Based on the results on net reproduction rate, intrinsic rate of increase and generation time, calculated for P. nigrispinus, the populations improved according to the plant species available and showed better response when confined with prey on...


A alimentação em plantas pelo percevejo predador Podisus nigrispinus (Dallas) tem produzido efeitos na sua biologia que variam com a espécie de planta utilizada. Este estudo foi conduzido com o objetivo de avaliar o desenvolvimento e a reprodução de P. nigrispinus confinado sobre as folhas de algodoeiro Gossypium hirsutum cv. Precoce CNPA1 e tomateiro industrial Lycopersicum esculentum cv. IPA5, e alimentados com pupas de Tenebrio molitor (L.). Ninfas e adultos de P. nigrispinus foram confinados com presa sobre algodoeiro, presa sobre tomateiro, com presa e água, e somente presa. O acesso às plantas foi obtido confinando os predadores nas folhas das plantas cultivadas em vasos. Ninfas confinadas em algodoeiro e tomateiro mais presa apresentaram menor duração no segundo e quinto ínstares. No entanto, o menor período ninfal foi observado para ninfas confinadas em algodoeiro mais presa. A sobrevivência de ninfas em cada ínstar e em todo o estágio ninfal foi menor para ninfas mantidas somente com presa comparado com aquelas com presa mais água e com presa sobre a planta. A disponibilidade do algodoeiro juntamente com a presa produziu ninfas de quinto ínstar mais pesadas, quando comparado com o tomateiro mais presa, água mais presa, e somente presa. O peso de adultos na emergência foi menor apenas quando os insetos tiveram acesso somente à presa. No entanto, fêmeas de P. nigrispinus confinadas sobre folhas de algodoeiro com presa ou mantidas com presa e água apresentaram significativo aumento de peso ao iniciar a reprodução, enquanto fêmeas confinadas sobre folhas de tomateiro ou somente com presa não variaram seu peso. A disponibilidade do algodoeiro e do tomateiro proporcionou aumento na produção de ovos e longevidade de P. nigrispinus. Além disso, as fêmeas mantidas com presa sobre as folhas de algodoeiro apresentaram maior taxa de oviposição. Baseado nos parâmetros populacionais taxa reprodutiva, taxa intrínseca de crescimento populacional...

20.
Neotrop. entomol ; 30(4): 647-654, Dec. 2001. graf, tab
Artículo en Portugués | LILACS | ID: lil-514518

RESUMEN

The predation rate of unmated and mated females of Podisus nigrispinus (Dallas) was evaluated on different densities of Alabama argillacea (Huebner) caterpillars (50 ± 10 mg), in laboratory and field conditions. In the laboratory, the predator females were maintained in 500 ml plastic jars with five different densities of prey (one, two, four, eight, and 16). In the field, caterpillars at the same densities were caged on flowering cotton plants. Under both conditions, females gained weight and increased the predation rate when the availability of prey increased, although higher values were obtained for females kept in the laboratory. Weight gain and predation rate did not differ between unmated and mated females under both conditions. In the field, P. nigrispinus searched 94.7 percent of the available foliar area under low prey density, and 21.2 percent under high prey density. The estimated handling time and attack rate were, respectively, 3.37 ± 0,82h and 0.076 ± 0.013h-1 in the laboratory, and 3.33 ± 0.93h and 0.017 ± 0.003h-1 in the field. The functional response corresponded to a type II for both conditions. The number of killed caterpillars observed and estimated by the model were highly correlated for both laboratory (r = 0.78) and field (r = 0.70) conditions.


Avaliou-se a taxa de predação de fêmeas virgens ou acasaladas de Podisus nigrispinus (Dallas) em diferentes densidades de lagartas de Alabama argillacea (Huebner) em condições de laboratório e de campo. Em laboratório, empregaram-se potes plásticos de 500 ml contendo fêmeas do predador, uma folha de algodão e lagartas de A. argillacea (50 ± 10 mg) nas densidades de uma, duas, quatro, oito e 16 lagartas. No campo, algodoeiros na fase de florescimento foram engaiolados, sendo empregadas as mesmas densidades de lagartas que no laboratório. Em ambas as condições, as fêmeas de P. nigrispinus apresentaram ganho de peso e aumento de sua taxa de predação com o aumento da densidade de lagartas de A. argillacea, mas com valores maiores para fêmeas em laboratório. Nas duas condições, o ganho de peso e a taxa de predação foram semelhantes para fêmeas virgens ou acasaladas. No campo, P. nigrispinus explorou 94,7 por cento e 21,2 por cento da área foliar disponível na menor e maior densidade de presas, respectivamente. O tempo de manipulação e a taxa de ataque estimadas foram de 3,37 ± 0,82h e de 0,076 ± 0,013h-1 em laboratório, e de 3,33 ± 0,93h e de 0,017 ± 0,003h-1 em campo. A resposta funcional em laboratório e no campo foi caracterizada como do Tipo II. Os números observados e estimados de lagartas predadas pelo modelo foram significativamente correlacionados com as condições de laboratório (r = 0,78) e de campo (r = 0,70).

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