Isolation and detailed characterisation of the first sterigmatocystin hyperproducer mould strain in Hungary

AbstractAspergillus strains were isolated from Hungarian mills in order to get information on the appearance of sterigmatocystin (ST) producing moulds, whose presence has never been demonstrated in Hungary. Fungal isolates were classified into nine morphotypes, sections Nigri, Nidulantes, Versicolores (two morphotypes), Circumdati, Flavi (two morphotypes), Clavati and Terrei by classical mycological assays. ST producing strains could be classified into section Versicolores. ST production of the isolates was assessed by liquid and solid phase growth experiments and compared to ST producing reference strains: Aspergillus pepii SzMC 22332, Aspergillus versicolor SzMC 22333, Aspergillus griseoaurantiacus SzMC 22334 and Aspergillus nidulans RDIT9.32. Four of our isolates marked as Km11, Km14, Km26 and Km31 showed ST production in liquid medium. ST production on solid phase corn grit substrate was measured after three weeks of incubation, and Km26 isolate proved to be the most prominent with a toxin concentration of 277.1 μg g−1, surpassing all reference strains. The toxin-producing ability of Km26 isolate was also tested in a field experiment, where corn was infected. By the end of the experiment, ST level of 19.56 μg kg−1 was measured in infected corn.Molecular taxonomic identification of the Km26 strain was performed using internal transcribed spacer (ITS), calmodulin and tubulin sequence analyses. Based on these studies, strain Km26 was identified as Aspergillus creber.Here we report that an ST-producing A. creber strain has appeared in Hungary, and the Km26 strain is the first known extreme ST-producing mould in this country. As a result of climate change, aflatoxin B1 producing Aspergillus flavus strains have appeared in Hungary in the last decade. As strain Km26 is the only A. creber isolate in Hungary so far, there is no sign of mass prevalence, and due to the lower temperature optimum of the species compared to A. flavus, its appearance is probably not related to climate change.

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Formation of Nanocrystalline Silicon in Tin-Doped Amorphous Silicon Films

Ukrainian Journal of Physics ◽

10.15407/ujpe65.3.236 ◽

2020 ◽

Vol 65 (3) ◽

pp. 236

Author(s):

R. M. Rudenko ◽

O. O. Voitsihovska ◽

V. V. Voitovych ◽

M. M. Kras’ko ◽

A. G. Kolosyuk ◽

...

Keyword(s):

Amorphous Silicon ◽

Crystalline Silicon ◽

Solid Phase ◽

Nanocrystalline Silicon ◽

Recrystallization Temperature ◽

Nanocrystalline Phase ◽

Silicon Phase ◽

Silicon Nanocrystallites ◽

Lower Temperature ◽

Two Stages

The process of crystalline silicon phase formation in tin-doped amorphous silicon (a-SiSn) films has been studied. The inclusions of metallic tin are shown to play a key role in the crystallization of researched a-SiSn specimens with Sn contents of 1–10 at% at temperatures of 300–500 ∘C. The crystallization process can conditionally be divided into two stages. At the first stage, the formation of metallic tin inclusions occurs in the bulk of as-precipitated films owing to the diffusion of tin atoms in the amorphous silicon matrix. At the second stage, the formation of the nanocrystalline phase of silicon occurs as a result of the motion of silicon atoms from the amorphous phase to the crystalline one through the formed metallic tin inclusions. The presence of the latter ensures the formation of silicon crystallites at a much lower temperature than the solid-phase recrystallization temperature (about 750 ∘C). A possibility for a relation to exist between the sizes of growing silicon nanocrystallites and metallic tin inclusions favoring the formation of nanocrystallites has been analyzed.

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Solid Phase Growth of some Metal and Metal Oxide Thin Films on Sapphire and Quartz Glass Substrates

Materials Science Forum ◽

10.4028/www.scientific.net/msf.753.505 ◽

2013 ◽

Vol 753 ◽

pp. 505-509

Author(s):

Yuichi Sato ◽

Toshifumi Suzuki ◽

Hiroyuki Mogami ◽

Fumito Otake ◽

Hirotoshi Hatori ◽

...

Keyword(s):

Thin Films ◽

Quartz Glass ◽

Glass Substrate ◽

Solid Phase ◽

Quartz Glass Substrate ◽

Heteroepitaxial Growth ◽

Phase Growth ◽

Single Crystalline ◽

Glass Substrates ◽

Amorphous Quartz

Solid phase growth of thin films of copper (Cu), aluminum (Al) and zinc oxide (ZnO) on single crystalline sapphire and quartz glass substrates were tried by heat-treatments and their crystallization conditions were investigated. ZnO thin films relatively easily recrystallized even when they were deposited on the amorphous quartz glass substrate. On the other hand, Cu and Al thin films hardly recrystallized when they were deposited on the quartz glass substrate. The metal thin films could be recrystallized at only extremely narrow windows of the heat-treatment conditions when they were deposited on the single crystalline sapphire substrate. The window of the solid phase heteroepitaxial growth condition of the Al film was wider than that of the Cu film.

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Transfer-free fabrication of graphene field effect transistor arrays using solid-phase growth of graphene on a SiO2/Si substrate

Applied Physics Letters ◽

10.1063/1.4829137 ◽

2013 ◽

Vol 103 (18) ◽

pp. 183114 ◽

Cited By ~ 14

Author(s):

Masato Tamaoki ◽

Hideki Imaeda ◽

Shigeru Kishimoto ◽

Takashi Mizutani

Keyword(s):

Field Effect ◽

Field Effect Transistor ◽

Solid Phase ◽

Phase Growth ◽

Si Substrate ◽

Graphene Field Effect Transistor ◽

Effect Transistor

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Solid Phase Growth of Nickel Silicides in Polycrystalline Si Film on SiO2 with Cl Plasma Containing NiCl

ECS Meeting Abstracts ◽

10.1149/ma2012-02/2/38 ◽

2012 ◽

Keyword(s):

Solid Phase ◽

Phase Growth ◽

Nickel Silicides

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Dopant redistribution during the solid‐phase growth of CrSi2on Si(100)

Journal of Applied Physics ◽

10.1063/1.341333 ◽

1988 ◽

Vol 64 (8) ◽

pp. 4187-4193 ◽

Cited By ~ 13

Author(s):

A. Rockett ◽

J. E. Greene ◽

H. Jiang ◽

M. Östling ◽

C. S. Petersson

Keyword(s):

Solid Phase ◽

Phase Growth ◽

Dopant Redistribution

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Broad Diversity of Ralstonia solanacearum Strains in Cameroon

Plant Disease ◽

10.1094/pdis-93-11-1123 ◽

2009 ◽

Vol 93 (11) ◽

pp. 1123-1130 ◽

Cited By ~ 43

Author(s):

Gabriel Mahbou Somo Toukam ◽

Gilles Cellier ◽

Emmanuel Wicker ◽

Caroline Guilbaud ◽

Rémi Kahane ◽

...

Keyword(s):

Genetic Diversity ◽

Ralstonia Solanacearum ◽

Central Africa ◽

Sequence Analyses ◽

Chain Reaction ◽

Specific Pcr ◽

Economic Threat ◽

The Indian Ocean ◽

Polymerase Chain ◽

Reference Strains

In 2005, an extensive survey of bacterial wilt in Cameroon collected 110 strains of Ralstonia solanacearum from wilting tomato, potato, pepper, huckleberry (Solanum scabrum), sesame, and amaranth. The genetic diversity and phylogeny of selected strains from Cameroon were assessed by multiplex–polymerase chain reaction (PCR), race 3/biovar 2–specific PCR, and sequence analyses of the mutS and egl genes. These data were compared with those from 33 reference strains covering the known diversity within the R. solanacearum species complex. Strains isolated in Cameroon clustered into three of the four known phylotypes: I (Asian), II (American), and III (African). Lowland tomato strains belonged to phylotype I and were quite homogeneous. The strains belonging to phylotype II were genetically diverse, and partitioned into subclusters IIA and IIB (sequevar 1, race 3/biovar 2). Cameroon strains in the African phylotype III were distinct from reference strains from Zimbabwe or the Indian Ocean, highlighting the genetic diversity present within this phylotype. Strains from potatoes growing in the highlands of West Cameroon fell into both phylotypes II (race 3/biovar 2) and III. These phylotype II and III highland strains attacked both potato and tomato and could therefore pose an economic threat to potato and tomato crops throughout Central Africa. This is the first comprehensive report on the genetic diversity of R. solanacearum strains in Cameroon.

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Solid Phase Growth Of β-FeSi2 on Si (111) with FeSi Source and Its Application to Photonic Devices

ECS Meeting Abstracts ◽

10.1149/ma2013-01/2/27 ◽

2013 ◽

Keyword(s):

Solid Phase ◽

Photonic Devices ◽

Phase Growth

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Mechanics of Growing Solids and Phase Transitions

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.535-536.89 ◽

2013 ◽

Vol 535-536 ◽

pp. 89-93 ◽

Cited By ~ 19

Author(s):

Alexander V. Manzhirov

Keyword(s):

Phase Transition ◽

Phase Transitions ◽

Mathematical Theory ◽

Solid Phase ◽

Phase Growth ◽

Main Attention ◽

Transition Processes

Phase transitions can be usually observed in nature and technology which effectively utilize certain types of these transitions. An approach to modeling phase transition processes on the basis of the mathematical theory of growing solids is developed. Liquid-solid and gas-solid phase transitions are under consideration. Main attention is paid to the processes of solid phase growth and deformation.

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