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1.
J Nematol ; 522020.
Artigo em Inglês | MEDLINE | ID: mdl-33829207

RESUMO

During a field survey for entomopathogenic nematodes in Georgia, in the territory of Borjomi-Kharagauli, a nematode population was isolated from the body of single dead beetle of Lucanus ibericus Motschulsky 1845 (Coleoptera: Lucanidae). Based on morphological characters and molecular analyses, the nematode species is identical to Pelodera strongyloides (Schneider, 1860, 1866), being the first record of this species in Georgia. Morphometrics of the Georgian population agree with the original description, and females differ from males by very few characters. The Georgian population of P. strongyloides was molecularly characterized by sequencing the D2 to D3 expansion domains of the 28S rRNA gene and two new molecular markers as the ITS and the mitochondrial COI gene. Phylogenetic analyses revealed that all P. strongyloides sequences grouped together along with all other Pelodera species.

2.
J Helminthol ; 89(3): 359-66, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24721783

RESUMO

An investigation was carried out on the distribution and biodiversity of steinernematid and heterorhabdtid entomopathogenic nematodes (EPN) in nine regions of Italy in the period 1990-2010. More than 2000 samples were collected from 580 localities and 133 of them yielded EPN specimens. A mapping of EPN distribution in Italy showed 133 indigenous EPN strains belonging to 12 species: 43 isolates of Heterorhabditis bacteriophora, 1 of H. downesi, 1 of H. megidis, 51 of Steinernema feltiae, 12 of S. affine, 4 of S. kraussei, 8 of S. apuliae, 5 of S. ichnusae, 3 of S. carpocapsae, 1 of S. vulcanicum, 3 of Steinernema 'isolate S.sp.MY7' of 'S. intermedium group' and 1 of S. arenarium. Steinernematids are more widespread than heterorhabditids and S. feltiae and H. bacteriophora are the most commonly encountered species. Sampling sites were grouped into 11 habitats: uncultivated land, orchard, field, sea coast, pinewood, broadleaf wood, grasslands, river and lake borders, caves, salt pan and moist zones; the soil texture of each site was defined and the preferences of habitat and soil texture of each species was assessed. Except for the two dominant species, S. feltiae and H. bacteriophora, EPN occurrence tends to be correlated with a specific vegetation habitat. Steinernema kraussei, H. downesi and H. megidis were collected only in Sicily and three of the species recently described - S. apuliae, S. ichnusae and S. vulcanicum - are known only from Italy and seem to be endemic.


Assuntos
Biodiversidade , Nematoides/classificação , Nematoides/isolamento & purificação , Rabditídios/parasitologia , Animais , DNA de Helmintos , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Ecossistema , Itália , Dados de Sequência Molecular , Nematoides/genética , Análise de Sequência de DNA
3.
J Chromatogr A ; 1007(1-2): 93-100, 2003 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-12924555

RESUMO

A new method for the determination of Pd by ion chromatography and spectrophotometric detection has been developed. The technique is based on the separation of palladium as PdCl4(2-) by anion exchange and on the detection, at a wavelength of 407 nm, of metal as PdI4(2-) after a post-column reaction with KI. The column used was an IonPac AS4 with HCl and HClO4 eluents. The eluent concentration and composition of post-column reagent were optimised in order to obtain the best separation and sensitivity for Pd. In order to reduce the detection limit, an on-line preconcentration step, has been optimised. The method, as developed, was suitable for palladium determination within a 300 ng/l D.L. value. The method applied to a BCR reference material (CRM 277, estuarine sediment) gave satisfactory results in agreement with the certified value within a D.L. value of 1.3 microg/l for the real sample.


Assuntos
Cromatografia por Troca Iônica/métodos , Espectrofotometria/métodos , Resinas de Troca Aniônica , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
J Chromatogr A ; 997(1-2): 51-63, 2003 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-12830876

RESUMO

A new method for palladium and platinum direct determination in environmental samples is proposed by coupling ion chromatography with quadrupole inductively coupled plasma MS. In order to optimise Pd and Pt separation and to minimise interference from matrix in real samples, several anionic and cationic stationary phases have been compared at different mobile phase compositions. In particular, the effect of acidity and of the addition of oxalic acid to the eluent on separation and detection performance has been studied, and the anion-exchange column AG11 turned out to be more suitable. After chromatographic and mass spectrometer parameter optimisation, several potential interferences and the main quality parameters of the method, according to the Eurachem-CITAC recommendations, were evaluated: the detection limit for Pt was 5 ng l(-1) while the value for Pd was 230 ng l(-1). The method was successfully employed in the determination of platinum group elements in urban road dust and atmospheric particulates and the complete absence of matrix spectral interferences was demonstrated.


Assuntos
Cromatografia/métodos , Poluentes Ambientais/análise , Paládio/análise , Platina/análise , Análise Espectral/métodos , Ânions , Cátions , Cromatografia por Troca Iônica/métodos , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Ácido Oxálico , Controle de Qualidade , Sensibilidade e Especificidade
5.
J Chromatogr A ; 920(1-2): 283-9, 2001 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-11453011

RESUMO

Liquid chromatographic methods, based on reversed-phase (RP) and anion-exchange mechanisms, have been developed for chloral hydrate determination. Both methods are preceeded by derivatization of chloral hydrate. For RP separations, different reagents [namely dansylhydrazine and o-(4-nitrobenzyl)hydroxylamine] have been studied, but the best results have been achieved using 1,2-benzenedithiol with UV detection at 220 nm. The anion-exchange method is based on derivatization with NaOH to form sodium formate that is then analyzed by anion-exchange, with suppressed conductivity detection. Derivatization conditions were optimized in order to reach the best yield of reaction. The optimization of the procedure allowed to determine chloral hydrate with detection limits as low as 0.2 microg/l with good linearity and reproducibility. The anion-exchange method was also applied for chloral hydrate determination in a drinking water sample. A preconcentration procedure has also been studied.


Assuntos
Hidrato de Cloral/análise , Cromatografia por Troca Iônica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta , Abastecimento de Água/análise
6.
Parassitologia ; 38(3): 521-4, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9257341

RESUMO

Scanning electron microscopy (SEM) observations on the mouthparts of four species of blood-sucking muscid symbovine flies (Stomoxys calcitrans Linnaeus, Haematobia irritans Linnaeus, H. titillans Bezzi, and Haematobosca stimulans Meigen) are described. The morphology of some structures (haustellum, prestomal teeth and petiolate blades) is compared in order to draw attention to those features involved in the feeding process on the hosts.


Assuntos
Dípteros/anatomia & histologia , Animais , Bovinos/parasitologia , Dípteros/ultraestrutura , Cabeça/anatomia & histologia , Itália , Microscopia Eletrônica de Varredura , Especificidade da Espécie
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