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1.
Phys Rev Lett ; 131(25): 250802, 2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-38181346

RESUMEN

We consider communication scenarios where one party sends quantum states of known dimensionality D, prepared with an untrusted apparatus, to another, distant party, who probes them with uncharacterized measurement devices. We prove that, for any ensemble of reference pure quantum states, there exists one such prepare-and-measure scenario and a linear functional W on its observed measurement probabilities, such that W can only be maximized if the preparations coincide with the reference states, modulo a unitary or an antiunitary transformation. In other words, prepare-and-measure scenarios allow one to "self-test" arbitrary ensembles of pure quantum states. Arbitrary extreme D-dimensional quantum measurements, or sets thereof, can be similarly self-tested. Our results rely on a robust generalization of Wigner's theorem, a well-known result in particle physics that characterizes physical symmetries.

2.
Pathogens ; 12(1)2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36678350

RESUMEN

In the first part of this two-piece publication, the isolation, identification and in vitro characterization of ten endophytic Trichoderma isolates were reported. Here we report the ability of two different mixes of some of these isolates (Trichoderma simmonsii, Trichoderma orientale and Trichoderma gamsii as well as of Trichoderma afroharzianum and T. simmonsii) to colonize and stimulate the growth of grapevines. Two commercial vineyards about 400 km away from the site of isolation were used as experimental fields, from which the strains of three Trichoderma species were re-isolated up to four years after rootstock soaking treatment with conidiospores, performed before planting. The treatments decreased the overall percentage of lost plants of about 30%, although a low number of lost plants (about 5%) were observed also in the control plot. For all cultivars and clones, the Trichoderma treatments significantly increased both the bud burst ratio and bud burst vigor index. In addition, the grape must parameters such as the Brix degrees, as well as the extract, the D-glucose and the D-fructose concentrations all appeared to be improved, suggesting a potentially higher ethanol content of the produced wine. We conclude that grapevine-endophytic Trichoderma isolates promote plant growth, which could be a useful feature for sustainable agriculture in general and integrated plant production in particular.

3.
Pathogens ; 10(12)2021 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-34959567

RESUMEN

This paper reports on the identification and in vitro characterization of several Trichoderma strains isolated from the Tokaj Wine Region in North-East Hungary. Ten isolates were analyzed and found to consist of six individual species-T. gamsii, T. orientale, T. simmonsii, T. afroharzianum, T. atrobrunneum and T. harzianum sensu stricto. The growth potential of the strains was assessed at a range of temperatures. We also report here on the in vitro biocontrol properties and fungicide tolerance of the most promising strains.

4.
Pathogens ; 10(2)2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33494548

RESUMEN

In this research, our aim was to assess the occurrence of Staphylococcus aureus in a Hungarian large-scale dairy farm during the S. aureus control program conducted in the course of our studies. Furthermore, the phenotypic and genotypic properties of the isolates (type of haemolysis, antibiotic susceptibility, staphylococcal enterotoxin (SE) gene carrying ability and spa type) were determined. S. aureus was detected in all bulk tank milk samples collected during this study. Two different spa types were identified among the 17 strains isolated in the farm. A total of 14 of the 17 studied strains (82%) showed ß-haemolysis on blood agar, 2/17 strains (12%) expressed double zone and 1/17 strains (6%) showed weak ß-haemolysis. All strains were susceptible to most antibiotics tested (cefoxitin, chloramphenicol, clindamycin, erythromycin, gentamicin, tetracycline and trimethoprim/sulphamethoxazole), but all strains were resistant to penicillin G. A total of 11 of the 17 strains (65%) were found to harbour seg, sei, selm, seln, selo genes; 4/17 strains (24%) harboured sei, selm, seln, selo genes and 2/17 strains (11%) harboured sei gene. Since the new SEs/SEls can also cause foodborne outbreaks potentially and all strains were found to be resistant to penicillin G, it is essential to decrease and keep the prevalence of S. aureus low in the dairy farm and the implementation of the S. aureus control program is also highly justified. The results showed that the S. aureus count decreased by the end of our studies, so the control program was proved to be effective.

5.
Fogorv Sz ; 109(2): 56-60, 2016 Jun.
Artículo en Húngaro | MEDLINE | ID: mdl-27544965

RESUMEN

In the past years antibacterial and antifungal polymers had become the focus of medical research. Polyethylenimine (PEI) and poliamidoamin had been proven the most effective polymers. The data shown in this short review discuss the chemical structure, pharmacological effects and medical use of PEI. Report in the international literature only gives examples of experimental dental appliance of PEI in sealers and filling materials. Because of the growing interest in the subject of PEI we find it important to inform the domestic dental society of cationic polymers.


Asunto(s)
Antibacterianos/uso terapéutico , Antifúngicos/uso terapéutico , Odontología , Polietileneimina/uso terapéutico , Polímeros , Antibacterianos/farmacología , Antifúngicos/farmacología , Odontología/métodos , Humanos , Polietileneimina/farmacología
6.
J Sci Food Agric ; 92(9): 1931-6, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22246719

RESUMEN

BACKGROUND: Lactobacillus and Bifidobacterium strains are present in a great variety of habitats, including fermented products, probiotic concoctions and the human colon. Some species are so closely related that it is difficult to distinguish them by microbiological techniques. Nevertheless, discrimination of isolates is an important issue in respect of application, and molecular methods such as restriction fragment length polymorphism (RFLP), random amplification of polymorphic DNA (RAPD) or species-specific polymerase chain reaction (PCR) might help in resolving this problem. In this study, PCR, RFLP and sequencing were applied to identify lactobacilli and bifidobacteria originating from various sources and the DSMZ strain collection. RESULTS: The microbiological composition of foods was analysed by molecular methods. Using species-specific PCR primers, three restriction enzymes (AluI, HhaI and RsaI) and sequencing, three Bifidobacterium and six Lactobacillus reference strains could be distinguished and four additional lactobacilli of food origin were identified. CONCLUSION: A combination of three molecular methods resulted in successful discrimination of nine reference strains and four isolates of food origin. Since these methods are not always accurate owing to their high genetic homogeneity, it is advisable to use more than one method for the identification of L. casei and closely related species.


Asunto(s)
Bifidobacterium/genética , Microbiología de Alimentos , Lactobacillus/genética , Tipificación Molecular/métodos , Reacción en Cadena de la Polimerasa/métodos , Mapeo Restrictivo/métodos , Análisis de Secuencia de ADN/métodos , Bifidobacterium/clasificación , Análisis de los Alimentos , Humanos , Lactobacillus/clasificación , Polimorfismo de Longitud del Fragmento de Restricción , Especificidad de la Especie
7.
Mycol Res ; 113(Pt 2): 222-9, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19015029

RESUMEN

Heterokaryon incompatibility among Aspergillus niger strains is a widespread phenomenon that is observed as the inability to form stable heterokaryons. The genetic basis of heterokaryon incompatibility reactions is well established in some sexual filamentous fungi but largely unknown in presumed asexual species, such as A. niger. To test whether the genes that determine heterokaryon incompatibility in Neurospora crassa, such as het-c, vib-1 and pin-c, have a similar function in A. niger, we performed a short in silico search for homologues of these genes in the A. niger and several related genomes. For het-c, pin-c and vib-1 we did indeed identify putative orthologues. We then screened a genetically diverse worldwide collection of incompatible black Aspergilli for polymorphisms in the het-c orthologue. No size variation was observed in the variable het-c indel region that determines the specificity in N. crassa. Sequence comparison showed only minor variation in the number of glutamine coding triplets. However, introduction of one of the three N. crassa alleles (het-c2) in A. niger by transformation resulted in an abortive phenotype, reminiscent of the heterokaryon incompatibility in N. crassa. We conclude that although the genes required are present and the het-c homologue could potentially function as a heterokaryon incompatibility gene, het-c has no direct function in heterokaryon incompatibility in A. niger because the necessary allelic variation is absent.


Asunto(s)
Aspergillus niger/genética , Proteínas Fúngicas/genética , Secuencia de Aminoácidos , ADN de Hongos/genética , Genes Fúngicos , Datos de Secuencia Molecular , Neurospora crassa/genética , Fenotipo , Polimorfismo Genético , Alineación de Secuencia , Análisis de Secuencia de ADN
8.
Bioresour Technol ; 96(7): 779-84, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15607190

RESUMEN

Nitrate-dependent salicylate degradation by the denitrifying Pseudomonas butanovora was investigated and the molar ratio of the cometabolism under anaerobic circumstances was determined. The bacterium was able to utilize salicylate as an electron donor for the reduction of nitrate. Salicylate was eliminated via catechol, which is degraded by means of catechol 2,3-oxygenases (meta-cleavage), forming 2-hydroxymuconic semialdehyde. The molar ratios of NO(3)(-)-N:salicylate existing during the experiment accorded well with the assumed 1:1 molar ratio. The tolerances of the growth, the salicylate degradation and the denitrification of P. butanovora to various heavy metal ions were also studied. Although the strain was tolerant to Pb(2+) and Cu(2+) up to 1 mM in complete medium, salicylate utilization took place only up to a concentration of 0.1 mM for both heavy metal ions. Of the heavy metal ions investigated, Cd(2+) (at a concentration of 0.05 mM) displayed the highest inhibitory effect on salicylate degradation by P. butanovora.


Asunto(s)
Nitratos/metabolismo , Pseudomonas/metabolismo , Salicilatos/metabolismo , Anaerobiosis , Catecoles/química , Catecoles/metabolismo , Proliferación Celular/efectos de los fármacos , Microbiología Industrial/métodos , Metales Pesados/metabolismo , Metales Pesados/farmacología , Oxigenasas/metabolismo , Pseudomonas/crecimiento & desarrollo
9.
Res Microbiol ; 154(8): 593-600, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14527661

RESUMEN

Fungal polyketide synthases are responsible for the biosynthesis of several mycotoxins and other secondary metabolites. The aim of our work was to investigate the diversity of polyketide synthases in Aspergillus species using two approaches: PCR amplification using oligonucleotide primers, and bioinformatics. Ketosynthase domain probes amplified DNA fragments of about 700 bp in each examined isolate. Sequences of these domains were aligned and analyzed by phylogenetic methods. The ketosynthase domain sequences were highly diverse indicating that they most probably represent polyketide synthases responsible for different functions. A. albertensis and A. niger ketosynthase domain sequences clustered together with sequences of genes required for pigment biosynthesis (wA) in A. nidulans and P. patulum, while the ketosynthase domain sequence of A. muricatus was most closely related to an A. parasiticus wA type domain sequence, and those of the A. ochraceus isolates formed a distinct clade on the tree. These sequences were highly homologous to an A. terreus naphthopyrone synthase gene. An Aspergillus fumigatus genomic database was also searched for ketosynthase domain sequences, which have been included in the phylogenetic analysis. Altogether 14 putative ketosynthase domain sequences were identified. Clustering of the ketosynthase domain sequences correlated well with the type of metabolites produced by the corresponding polyketide synthases. At least 8 clusters with putative ketosynthase domain sequences of unknown function have been identified. Further studies are in progress to clarify the role of some of the identified polyketide synthase genes.


Asunto(s)
Aspergillus/enzimología , Aspergillus/genética , Complejos Multienzimáticos/genética , Secuencia de Aminoácidos , ADN de Hongos/aislamiento & purificación , Genes Fúngicos , Datos de Secuencia Molecular , Complejos Multienzimáticos/química , Ocratoxinas/biosíntesis , Filogenia , Reacción en Cadena de la Polimerasa , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 67(6 Pt 1): 061802, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16241249

RESUMEN

We study the creep rupture of fiber composites in the framework of fiber bundle models. Two fiber bundle models are introduced based on different microscopic mechanisms responsible for the macroscopic creep behavior. Analytical and numerical calculations show that above a critical load the deformation of the creeping system monotonically increases in time resulting in global failure at a finite time t(f), while below the critical load the system suffers only partial failure and the deformation tends to a constant value giving rise to an infinite lifetime. It is found that approaching the critical load from below and above the creeping system is characterized by universal power laws when the fibers have long-range interaction. The lifetime of the composite above the critical point has a universal dependence on the system size.

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