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1.
Exp Appl Acarol ; 86(2): 257-269, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35147811

RESUMEN

Donkeys (Equus asinus) are rustic animals, but in Africa's poorest regions, they can present multiple health problems, including tick infestation. The study's objective was to determine the species composition of ticks that infest donkeys in Maputo Province (Mozambique). Ticks were collected in five conveniently selected southern districts of Maputo Province (Moamba, Matutuíne, Marracuene, Boane, and Matola) and were identified to species level using a stereoscopic microscope with the aid of dichotomous identification keys. In total, 500 ticks were collected from all 88 selected donkeys. Three genera of ticks were identified, namely Rhipicephalus (97.2%; 486/500), Amblyomma (2.2%; 11/500), and Hyalomma (0.6%; 3/500). Seven species were identified, of which Rhipicephalus evertsi evertsi with 50.4% (252/500) was the most prevalent, followed by Rhipicephalus appendiculatus (27.4%; 137/500), Rhipicephalus turanicus (11.6; 10/500), Rhipicephalus (boophilus) microplus (6.8; 20/500), Amblyomma hebraeum (2.2%; 11/500), Rhipicephalus sanguineus (1%; 5/500) and Hyalomma truncatum (0.6%; 3/500). Rhipicephalus evertsi evertsi occurred in all locations, whereas Hyalomma truncatum occurred only in the Boane district. Males were the most prevalent (67.2%; 336/500). The study revealed that donkeys in Maputo Province were infested with seven tick species of which R. evertsi evertsi was the main species.


Asunto(s)
Equidae/parasitología , Ixodidae , Rhipicephalus , Infestaciones por Garrapatas , Animales , Masculino , Mozambique/epidemiología , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/veterinaria
2.
Sci Rep ; 13(1): 6169, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-37061537

RESUMEN

Leaf-cutting ants of the genera Atta and Acromyrmex (Hymenoptera: Formicidae) are the most important pests in forest and agricultural plantations and livestock. Toxic baits are the main method to manage these insects. The objective was to determine whether the behavior of allogrooming, touch, and self-grooming among Atta sexdens rubropilosa Forel, 1908 (Hymenoptera: Formicidae) workers disperse the fungicide quinone inside inhibitor and whether this product is toxic to them. This fungicide was applied, topically, in groups of workers and the social interactions between them and their mortality with and without the fungicide were evaluated. The interactions and the quinone inside inhibitor fungicide contamination increased with the number of leaf-cutting ant workers per group. Excessive touches, with subsequent allogrooming, and self-grooming among the ant workers dispersed the quinone inside the inhibitor fungicide causing 100% mortality and indicating its toxicity to this insect. The hypothesis that social interactions contaminated ant colony mates and the toxicity of the fungicide quinone inside inhibitor to workers of the leaf-cutting ant A. sexdens rubropilosa was proven.


Asunto(s)
Fungicidas Industriales , Interacción Social , Animales , Fungicidas Industriales/toxicidad , Quinonas
3.
Int J Chron Obstruct Pulmon Dis ; 18: 1899-1908, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37662489

RESUMEN

Background: Chronic obstructive pulmonary disease (COPD) worsens prognosis in patients with coronary artery disease (CAD). However, the cardiovascular prognosis in patients with stable or mildly symptomatic COPD remains unclear. Here, we sought to determine the long-term cardiovascular events in patients with subclinical or early-stage COPD with concomitant CAD. Methods: This was a longitudinal analytical study involving 117 patients with suspected or established CAD who underwent assessment of pulmonary function by spirometry and who were followed up for six years (March 2015-January 2021). The patients were divided into two groups, one comprising COPD (n=44) and the other non-COPD (n=73) patients. Cox regression was used to evaluate the association between COPD and cardiovascular events, with adjustment for the established CAD risk factors, and the effect size was measured by the Cohen test. Results: COPD patients were older (p=0.028), had a greater frequency of diabetes (p=0.026), were more likely to be smokers (p<0.001), and had higher modified Medical Research Council scores (p<0.001). There was no difference between the groups regarding gender, body mass index, hypertension, dyslipidemia, family history of CAD, and type of angina. CAD frequency and the proportion of patients with severe and multivessel CAD were significantly higher among COPD than among non-COPD patients (all p<0.001). At six-year follow-up, patients with COPD were more likely to have experienced adverse cardiovascular events than those without COPD (p<0.001; effect size, 0.720). After adjusting for established CAD risk factors, COPD occurrence remained an independent predictor for long-term adverse cardiovascular events (OR: 5.13; 95% CI: 2.29-11.50; p<0.0001). Conclusion: COPD was associated with increased severity of coronary lesions and a greater number of adverse cardiovascular events in patients with suspected or confirmed CAD. COPD remained a predictor of long-term cardiovascular events in stable patients with subclinical or early-stage of COPD, independently of the established CAD risk factors.


Asunto(s)
Sistema Cardiovascular , Enfermedad de la Arteria Coronaria , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Corazón , Pronóstico
4.
Neotrop Entomol ; 51(1): 73-80, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34787836

RESUMEN

Toxic baits, containing the active ingredients sulfluramid or fipronil, are the main methods to control leaf-cutting ants of the genera Atta Fabricius, 1805, and Acromyrmex Mayr, 1865 (Hymenoptera: Formicidae). However, the insecticide dispersion among members of the colony during the control needs further studies. We studied whether the behaviors of allogrooming, self-grooming, and contact among individuals spread the insecticides among those of the colony. The insecticides sulfluramid and fipronil (0.1% and 1.0% (w/w)) were applied topically in groups of workers of Atta sexdens (Linnaeus, 1758), and the social interactions among them with or without insecticide were studied. In addition, toxic baits (sulfluramid or fipronil) were provided to colonies and their behavioral acts were observed. At the end of the experiment, colony mortality, number and mass of dead workers, and mass of wet waste were compared between ant nests receiving baits and ants with topical application. In the topical application, behavioral analysis showed higher interaction between ants in the colonies and touch and allogrooming behaviors as the most frequent in those that received the concentrations of sulfluramid. In the baits, the behavior of licking the pellet and allogrooming was more frequent. Colony mortality was faster for those that received topical application, especially with the insecticide fipronil (0.1%). However, the number and mass of dead workers was similar between topical application and toxic baits. In the toxic baits, the licking behavior of the bait pellets and subsequent allogrooming probably dispersed the insecticides. In the topical application, the route of the insecticide occurred by excessive touches among workers, with subsequent allogrooming. Thus, allogrooming, self-grooming, and touching among workers increased the dispersion of insecticides among members of the ant colonies.


Asunto(s)
Hormigas , Insecticidas , Animales , Conducta Animal , Aseo Animal , Tacto
5.
Pest Manag Sci ; 77(10): 4411-4417, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33982404

RESUMEN

BACKGROUND: Leaf-cutting ants (LCAs) of the genera Atta and Acromyrmex (Hymenoptera: Formicidae) are important pests of forest plantations, agriculture and livestock. Toxic baits containing the active ingredients fipronil or sulfluramid are the main method used to control LCAs. Insecticide dispersion among members of an LCA colony during control with toxic bait is not well understood. The objective of the study was to determine whether self-grooming, allogrooming or touching behavior among Atta sexdens (Hymenoptera: Formicidae) workers disperses the insecticides fipronil and sulfluramid among members of the colony. The insecticides were topically applied on groups of A. sexdens workers and social interactions between ants with and without insecticide, and group mortality were evaluated. RESULTS: Behavioral analysis showed an increase in interaction among LCA workers as the numbers of individuals increased, with touches between workers being the most frequent behavior. The frequency of observed behaviors was higher in groups treated with sulfluramid compared with fipronil. The mortality of groups treated with fipronil was almost twice as high compared with ants treated with sulfluramid. The insecticides are probably dispersed by excessive touching among workers and subsequent self-grooming and allogrooming. CONCLUSION: These behaviors were responsible for the rapid dispersion of insecticides among members of the colony. Corroboration of the hypothesis that social interactions contaminate nestmates is a model for future studies on contamination of ant workers with active insecticide ingredients. © 2021 Society of Chemical Industry.


Asunto(s)
Hormigas , Insecticidas , Animales , Fluorocarburos , Humanos , Pirazoles , Interacción Social , Sulfonamidas
6.
Insects ; 8(2)2017 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-28598375

RESUMEN

The aim of this study was to determine whether worker self-grooming, allogrooming, and direct contact promotes the dispersal of substances among members of the colony. For this purpose, a tracer (Sudan III dye) was applied topically to a worker ant and the social interactions between the worker with the tracer and workers without the tracer were studied. Additionally, the worker heads were dissected to visualize whether or not the post-pharyngeal gland was stained. The post-pharyngeal glands from 50% to 70% of workers were stained depending on the size of the group. With the increase in the experimental group size, the frequency of interactions between workers increased, with touching being the most frequent behavior. The tracer dye was probably passed on by direct contact between workers, followed by self-grooming and allogrooming. These behaviors are responsible for the rapid dispersal of substances among colony members as observed in our experiment. The results therefore support the hypothesis that contact with substances promotes the contamination of nestmates, even in the absence of feeding, serving as a model for further studies on the contamination of workers with the active ingredients of insecticides.

7.
PLoS One ; 10(8): e0135234, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26252377

RESUMEN

The agriculture sector has historically been a major source of greenhouse gas (GHG) emissions into the atmosphere. Although the use of synthetic fertilizers is one of the most common widespread agricultural practices, over-fertilization can lead to negative economic and environmental consequences, such as high production costs, depletion of energy resources, and increased GHG emissions. Here, we provide an analysis to understand the evolution of cereal production and consumption of nitrogen (N) fertilizers in Brazil and to correlate N use efficiency (NUE) with economic and environmental losses as N2O emissions. Our results show that the increased consumption of N fertilizers is associated with a large decrease in NUE in recent years. The CO2 eq. of N2O emissions originating from N fertilization for cereal production were approximately 12 times higher in 2011 than in 1970, indicating that the inefficient use of N fertilizers is directly related to environmental losses. The projected N fertilizer forecasts are 2.09 and 2.37 million ton for 2015 and 2023, respectively. An increase of 0.02% per year in the projected NUE was predicted for the same time period. However, decreases in the projected CO2 eq. emissions for future years were not predicted. In a hypothetical scenario, a 2.39% increase in cereal NUE would lead to $ 21 million savings in N fertilizer costs. Thus, increases in NUE rates would lead not only to agronomic and environmental benefits but also to economic improvement.


Asunto(s)
Agricultura , Grano Comestible/crecimiento & desarrollo , Nitrógeno/química , Óxido Nitroso/química , Contaminantes Atmosféricos , Atmósfera , Brasil , Dióxido de Carbono/química , Ambiente , Fertilizantes , Gases , Efecto Invernadero , Metano/química , Modelos Estadísticos
8.
Bioresour Technol ; 101(7): 2545-8, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20007016

RESUMEN

The objective of this study was to evaluate the effect of log steaming and of the diametrical position of boards on the timber quality of Eucalyptus grandis. Logs with diameters between 20 and 25 cm, between 25 and 30 cm and between 30 and 35 cm were studied. Half of logs were kept in its original condition, and the other half was steamed at 90 degrees C for 20 h. Later, the logs were cut into flat saw boards, and defects due to growth stress relief were measured. The results show that: (1) boards from control logs show different magnitudes of cracking according to the diameter of the log and the diametrical position of the board; (2) boards from logs with diameters between 30 and 35 cm and those from next to the pith develop larger cracks; and (3) boards from steamed logs show a reduction in the magnitude of cracking and a homogenous distribution of this defect relative to diametrical position within the log.


Asunto(s)
Eucalyptus/química , Vapor , Madera/química , Estrés Mecánico
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