Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Polymers (Basel) ; 16(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38337333

RESUMO

This study addresses the challenges of modeling flexible connections in composite structures employing a polymeric adhesive layer. These types of connections provide a more uniform stress distribution compared to conventional rigid connectors. However, they lack standardized design rules and still require much research to sufficiently comprehend their properties. The novelty of this research lies in proposing an analytical solution to address these issues. Its aim is to investigate the influence of the stiffness of the polymer adhesive on the girder's deflection and on the maximum stresses in both the adhesive and concrete. The analyzed composite structure consists of a reinforced concrete (RC) slab and an RC beam connected with a layer of flexible polyurethane (FPU) adhesive. Analytical and numerical approaches for the description of the mechanical response of a composite bridge girder are presented. Another objective is to validate the analytical design formulas using 3D nonlinear numerical analysis, both in the case of uncracked and cracked concrete. Seven types of FPUs are tested in the uniaxial tension test, each examined at five strain rates. The obtained data is used to predict the mechanical response of the considered girder using finite element analysis (FEA) as well as with a simplified one-dimensional composite beam theory. Fair agreement is found between the FEA results and theoretical predictions. A comparison of the results obtained for these two models is performed, and the similarities and discrepancies are highlighted and discussed.

3.
J Appl Genet ; 64(3): 377-391, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37120451

RESUMO

Increased grain yield (GY) is the primary breeding target of wheat breeders. We performed the genome-wide association study (GWAS) on 168 elite winter wheat lines from an ongoing breeding program to identify the main determinants of grain yield. Sequencing of Diversity Array Technology fragments (DArTseq) resulted in 19,350 single-nucleotide polymorphism (SNP) and presence-absence variation (PAV) markers. We identified 15 main genomic regions located in ten wheat chromosomes (1B, 2B, 2D, 3A, 3D, 5A, 5B, 6A, 6B, and 7B) that explained from 7.9 to 20.3% of the variation in grain yield and 13.3% of the yield stability. Loci identified in the reduced genepool are important for wheat improvement using marker-assisted selection. We found marker-trait associations between three genes involved in starch biosynthesis and grain yield. Two starch synthase genes (TraesCS2B03G1238800 and TraesCS2D03G1048800) and a sucrose synthase gene (TraesCS3D03G0024300) were found in regions of QGy.rut-2B.2, QGy.rut-2D.1, and QGy.rut-3D, respectively. These loci and other significantly associated SNP markers found in this study can be used for pyramiding favorable alleles in high-yielding varieties or to improve the accuracy of prediction in genomic selection.


Assuntos
Estudo de Associação Genômica Ampla , Triticum , Triticum/genética , Melhoramento Vegetal , Mapeamento Cromossômico , Fenótipo , Grão Comestível/genética , Polimorfismo de Nucleotídeo Único/genética
4.
PLoS One ; 15(2): e0222375, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32017768

RESUMO

Fusarium head blight (FHB) is a devastating disease occurring in small grain cereals worldwide. The disease results in the reduction of grain yield, and mycotoxins accumulated in grain are also harmful to both humans and animals. It has been reported that response to pathogen infection may be associated with the morphological and developmental traits of the host plant, e.g. earliness and plant height. Despite many studies, effective markers for selection of barley genotypes with increased resistance to FHB have not been developed. In the present study, we investigated 100 recombinant inbred lines (RIL) of spring barley. Plants were examined in field conditions (three locations) in a completely randomized design with three replications. Barley genotypes were artificially infected with spores of Fusarium culmorum before heading. Apart from the main phenotypic traits (plant height, spike characteristic, grain yield), infected kernels were visually scored and the content of deoxynivalenol (DON) mycotoxin was investigated. A set of 70 Quantitative Trait Loci (QTLs) were detected through phenotyping of the mapping population in field conditions and genotyping using a barley Ilumina 9K iSelect platform. Six loci were detected for the FHB index on chromosomes 2H, 3H, 5H, and 7H. A region on the short arm of chromosome 2H was detected in which many QTLs associated with FHB- and yield-related traits were found. This study confirms that agromorphological traits are tightly related to FHB and should be taken into consideration when breeding barley plants for FHB resistance.


Assuntos
Fusarium/genética , Hordeum/microbiologia , Doenças das Plantas/genética , Locos de Características Quantitativas , Cromossomos de Plantas , Fusariose/genética , Fusarium/patogenicidade , Genótipo , Micotoxinas/análise , Doenças das Plantas/microbiologia
5.
Eur J Med Res ; 20: 100, 2015 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-26698837

RESUMO

PURPOSE OF REVIEW: We aim to illustrate the potential viability of MCTD as an underlying aetiology of Melkersson-Rosenthal syndrome. The case is probably the first description available in the literature of the Melkersson-Rosenthal as an early manifestation of mixed connective tissue disease. RECENT FINDINGS: The Melkersson-Rosenthal syndrome consists of a triad of recurrent lip and/or face swelling, fissured tongue, and intermittent facial palsy. Mixed connective tissue disease is a multisystemic disorder with overlapping features of systemic lupus erythematosus, scleroderma, and polymyositis, and is differentiated from them by a high titer of antibodies to ribonucleoprotein. The paper presents a case report of Melkersson-Rosenthal syndrome with an onset in childhood that derived from vasculitis that turned out to be an early manifestation of mixed connective tissue disease. We used MRI to evaluate patient's brain structure and Immunoblot Ena Profil 1 test to test serum autoantibodies level. The patient has a typical for Melkersson-Rosenthal syndrome triad of symptoms: bilateral facial nerve palsy, lingua plicata and facial oedema. Both TC and MRI of the head show no changes as well as laboratory tests except Anti-SS-A (Anti-Ro) and Anti-RNP autoantibody serum level that was highly positive. Neurological involvement of the MCTD usually includes, according to the frequency of the occurrence, trigeminal neuralgia, headaches, sensorineural hearing, cerebral haemorrhage, transverse myelitis, cauda equina syndrome, retinal vasculitis, progressive multifocal encephalopathy, and demyelinating neuropathy. For clinical practice it is important to remember that Melkersson-Rosenthal syndrome can also be the neurological manifestation of MCTD, especially when accompanied by other systemic symptoms.


Assuntos
Síndrome de Melkersson-Rosenthal/complicações , Doença Mista do Tecido Conjuntivo/etiologia , Adulto , Feminino , Humanos , Síndrome de Melkersson-Rosenthal/etiologia
6.
FEMS Microbiol Lett ; 219(1): 69-74, 2003 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-12594025

RESUMO

Fifteen (soil and intestinal) strains of Desulfovibrio desulfuricans species were typed by PCR method with the use of primers specific for repetitive extragenic palindromic (REP) and enterobacterial repetitive intergenic consensus (ERIC) sequences. As a result, characteristic DNA fingerprints for the strains were obtained. Moreover, the genetic profiles were found to be useful for typing and distinguishing the strains of D. desulfuricans. According to cluster analysis, PCR with primers complementary to the sequences REP appeared to be slightly more discriminatory than PCR with ERIC primers for the investigated strains. Distinct fingerprint patterns of two isolates derived from the same patient pointed to the different origin of both strains.


Assuntos
Impressões Digitais de DNA/métodos , Desulfovibrio/classificação , Variação Genética , Sequências Repetitivas de Ácido Nucleico/genética , Técnicas de Tipagem Bacteriana , Ceco/microbiologia , Primers do DNA , DNA Bacteriano/análise , Desulfovibrio/genética , Fezes/microbiologia , Humanos , Reação em Cadeia da Polimerase/métodos , Microbiologia do Solo , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...