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1.
Nanomaterials (Basel) ; 13(3)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36770424

RESUMO

Through the execution of scientific innovations, "smart materials" are shaping the future of technology by interacting and responding to changes in our environment. To make this a successful reality, proper component selection, synthesis procedures, and functional active agents must converge in practical and resource-efficient procedures to lay the foundations for a profitable and sustainable industry. Here we show how the reaction time, temperature, and surface stabilizer concentration impact the most promising functional properties in a cotton-based fabric coated with silver nanoparticles (AgNPs@cotton), i.e., the thermal and bactericidal response. The coating quality was characterized and linked to the selected synthesis parameters and correlated by a parallel description of "proof of concept" experiments for the differential heat transfer (conversion and dissipation properties) and the bactericidal response tested against reference bacteria and natural bacterial populations (from a beach, cenote, and swamp of the Yucatan Peninsula). The quantification of functional responses allowed us to establish the relationship between (i) the size and shape of the AgNPs, (ii) the collective response of their agglomerates, and (iii) the thermal barrier role of a surface modifier as PVP. The procedures and evaluations in this work enable a spectrum of synthesis coordinates that facilitate the formulation of application-modulated fabrics, with grounded examples reflected in "smart packaging", "smart clothing", and "smart dressing".

2.
PLoS One ; 15(5): e0232737, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32392234

RESUMO

The oceanographic conditions of the Pacific Ocean are largely modified by El Niño (EN), affecting several ecological processes. Parasites and other marine organisms respond to environmental variation, but the influence of the EN cycle on the seasonal variation of parasitic copepods has not been yet evaluated. We analysed the relation between infection parameters (prevalence and mean intensity) of the widespread parasitic copepods Caligus bonito and Charopinopsis quaternia in the dolphinfish Coryphaena hippurus and oceanography during the strong 2015-16 EN. Fish were collected from capture fisheries on the Ecuadorian coast (Tropical Eastern Pacific) over a 2-year period. Variations of sea surface temperature (SST), salinity, chlorophyll a (Chl-a), Oceanic Niño Index (ONI), total host length (TL) and monthly infection parameters of both copepod species were analysed using time series and cross-correlations. We used the generalised additive models for determine the relationship between environmental variables and infection parameters. The total body length of the ovigerous females and the length of the eggs of C. bonito were measured in both periods. Infection parameters of both C. bonito and Ch. quaternia showed seasonal and annual patterns associated with the variation of environmental variables examined (SST, salinity, Chl-a and ONI 1+2). Infection parameters of both copepod species were significantly correlated with ONI 1+2, SST, TL and Chl-a throughout the GAMLSS model, and the explained deviance contribution ranged from 16%-36%. Our results suggest than an anomaly higher than +0.5°C triggers a risen in infection parameters of both parasitic copepods. This risen could be related to increases in egg length, female numbers and the total length of the ovigerous females in EN period. This study provides the first evidence showing that tropical parasitic copepods are sensitive to the influence of EN event, especially from SST variations. The observed behaviour of parasitic copepods likely affects the host populations and structure of the marine ecosystem at different scales.


Assuntos
Copépodes/fisiologia , El Niño Oscilação Sul , Infecções/epidemiologia , Infecções/parasitologia , Perciformes/parasitologia , Clima Tropical , Animais , Feminino , Modelos Biológicos , Óvulo/fisiologia , Oceano Pacífico , Prevalência , Fatores de Tempo
3.
Int J Parasitol ; 41(13-14): 1403-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22079832

RESUMO

In September 2002, Hurricane Isidore devastated the Yucatán Peninsula, Mexico. To understand its effects on the parasites of aquatic organisms, we analyzed long-term monthly population data of the horn snail Cerithidea pliculosa and its trematode communities in Celestún, Yucatán, Mexico before and after the hurricane (February 2001 to December 2009). Five trematode species occurred in the snail population: Mesostephanus appendiculatoides, Euhaplorchis californiensis, two species of the genus Renicola and one Heterophyidae gen. sp. Because these parasites use snails as first intermediate hosts, fishes as second intermediate hosts and birds as final hosts, their presence in snails depends on food webs. No snails were present at the sampled sites for 6 months after the hurricane. After snails recolonised the site, no trematodes were found in snails until 14 months after the hurricane. It took several years for snail and trematode populations to recover. Our results suggest that the increase in the occurrence of hurricanes predicted due to climate change can impact upon parasites with complex life cycles. However, both the snail populations and their parasite communities eventually reached numbers of individuals and species similar to those before the hurricane. Thus, the trematode parasites of snails can be useful indicators of coastal lagoon ecosystem degradation and recovery.


Assuntos
Ecossistema , Caramujos/parasitologia , Trematódeos/fisiologia , Animais , Aves , Tempestades Ciclônicas , Peixes , Cadeia Alimentar , México , Dinâmica Populacional , Caramujos/crescimento & desenvolvimento , Trematódeos/isolamento & purificação , Clima Tropical
4.
J Parasitol ; 97(4): 695-706, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21506838

RESUMO

Cucullanus dodsworthi Barreto, 1922 was originally described from the checkered puffer fish, Sphoeroides testudineus (Linnaeus), from Brazilian waters. New material of this nematode species was recovered from the same type host species from Mexican waters off the Yucatán Peninsula. This material was compared with Brazilian specimens. Although Mexican material closely resembles the original description of C. dodsworthi in general appearance, previously undescribed characters, as observed by light and scanning electron microscopy, are described for the first time in this species from both Brazilian and Mexican specimens. These characters include lateral body alae or conspicuous lateral fields that begin in the cervical region and end anterior to first pair of adcloacal papillae in males and at the anus level in females, cephalic and caudal alae absent; presence of pseudobuccal capsule with simple buccal frame well sclerotized with dorsal arrow structures, lateral structures, and lateral reniform structures; deirids, excretory pore, and postdeirids; slight anal protuberance in both sexes, unpaired precloacal papilla in males, phasmids near pair 10 in males and near tail tip in females; female with protruding vulvar lips and smooth eggs. In the absence of better descriptions of this genus, it can be concluded that C. dodsworthi is the only species of marine Cucullanus from the Americas that possesses lateral body alae. Molecular characterization of C. dodsworthi with SSU (18S) and ITS2 rDNA genes is included. A preliminary genetic comparison between SSU rDNA of C. dodsworthi , Truttaedacnitis truttae (Fabricius, 1794), and Dichelyne mexicanus Caspeta-Mandujano, Moravec and Salgado-Maldonado, 1999 places C. dodsworthi as a putative sister taxon to T. truttae . The finding of C. dodsworthi in Mexican marine waters also represents a new geographical record.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridídios/classificação , Doenças dos Peixes/parasitologia , Tetraodontiformes/parasitologia , Animais , Ascaridídios/anatomia & histologia , Ascaridídios/genética , Infecções por Ascaridida/parasitologia , Brasil , DNA de Helmintos/química , DNA Ribossômico/química , Feminino , Masculino , Dados de Sequência Molecular , Filogenia
5.
J Parasitol ; 94(2): 326-34, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18564733

RESUMO

Temporal variation in the helminth parasite communities of the Pacific fat sleeper, Dormitator latifrons, from Tres Palos Lagoon, Guerrero, Mexico, was studied at the component community and infracommunity levels. In total, 185 host specimens were collected between April 2000 and March 2001. Eight parasite species were identified: Clinostomum complanatum, Echinochasmus leopoldinae, Ascocotyle (Phagicola) longa, Pseudoacanthostomum panamense, Saccocoelioides sp., Parvitaenia cochlearii, Neoechinorhynchus golvani, and Contracaecum sp. The communities had low numbers of parasite species and diversity, and contained only generalist parasites. Nested (nonrandom) species composition was observed in the infracommunities during all climatic seasons. The variation in nestedness intensity was attributed to a process of sequential colonization by the most common parasite species, because some were more abundant in the dry season, and others were more abundant in the rainy season.


Assuntos
Doenças dos Peixes/epidemiologia , Helmintíase Animal/epidemiologia , Perciformes/parasitologia , Análise de Variância , Animais , Feminino , Doenças dos Peixes/parasitologia , Helmintíase Animal/parasitologia , Helmintos/classificação , Masculino , México/epidemiologia , Prevalência , Estações do Ano , Água do Mar , Fatores de Tempo
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