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111.
This study deals with the mechanical analysis of glulam beams during changing relative humidity of the surrounding air. The computational part of the article includes two separate numerical procedures. First, the diffusion equation is solved to determine the temporal and spatial distribution of water content in the cross-section of the beam. The results of the first computational stage are used as the input data for the numerical analysis of mechanical response of the beam. The displacements and stress distribution at some characteristic cross-sections are presented. In the article some experimentally determined values of vertical displacements in the middle of span are shown and compared to the results of numerical analysis. 相似文献
112.
In this review, we summarize advances in the proteomic analysis of barley, especially those involving mass spectrometric detection. We focus particularly on monitoring of global protein expression in barley malt and changes in proteins during the technological processing of barley grains. 相似文献
113.
Journal of Plant Diseases and Protection - Field experiments were conducted over three consecutive growing seasons (20042–2006) to determine the effect of use of drift-reducing nozzles (ISO... 相似文献
114.
Emília Ondrušková Zuzana Hečková-Jánošíková Slavomír Adamčík Miriam Kádasi Horáková Dominika Rakúsová-Sládková Katarína Adamčíková 《Scandinavian Journal of Forest Research》2018,33(7):650-656
Dothistroma needle blight (DNB) has been observed in Slovakia during the last two decades. Up until 2017, Dothistroma septosporum has only been detected and molecularly confirmed to cause DNB in Slovakia. Here, we report the detection of Dothistroma pini at six localities around Slovakia, representing different plantation types. Four pine species (Pinus sylvestris, P. nigra, P. mugo and P. jeffreyi) were confirmed as hosts of D. pini in Slovakia, of which only P. mugo has been previously reported as host in Slovakia. Three gene regions (ITS, EF1 –α, and ß-tubulin) of each of the 13 isolates were sequenced and assigned as D. pini. Based on ITS sequences, the studied isolates represent the haplotypes Dp_HAP.1, Dp_HAP.2. Both mating types were detected but at different localities. Our results suggest that in addition to D. septosporum, D. pini may contribute to DNB also in Slovakia. 相似文献
115.
116.
Cherry laurel (Prunus laurocerasus) is a native plant species in Serbian forests, but is also widely used for ornamental plantings. Following two extremely wet summers in 2014 and 2015, in spring and summer of 2016 and 2017, numerous cherry laurel plants with symptoms indicative for Phytophthora diseases, like wilting and chlorosis of leaves, dieback and bleeding bark necroses, were recorded in a park in Belgrade and in two ornamental nurseries in central Serbia. From necrotic bark samples and rhizosphere soil, self‐sterile Phytophthora isolates with woolly colonies were obtained. Due to the production of ellipsoid and elongated, non‐papillate sporangia in water and of ornamented oogonia with two‐celled antheridia in mating tests with tester strains of both Phytophthora × cambivora and P. cryptogea, these isolates were identified as P. ×cambivora which was confirmed by ITS sequence analysis. Pathogenicity of P. ×cambivora from cherry laurel (PCCL) was tested by inoculating one‐year‐old seedlings of cherry laurel under the bark. P. ×cambivora from European beech (PCB), and isolates of P. cactorum (CAC), P. cryptogea (CRY), P. plurivora (PLU) and P. ×serendipita (SER) were included as comparison. Three and a half months after inoculation, nine of the twelve plants in PCB, three in PCCL and CAC and two in PLU declined with longitudinal necroses and chlorosis, wilting and premature shedding of leaves. These results demonstrate the ability of P. ×cambivora to infect and cause decline of cherry laurel plants. The particularly high aggressiveness of the P. ×cambivora isolate from beech shows that this pathogen poses a serious risk to cherry laurel in the rare natural communities of cherry laurel and beech in Serbia. 相似文献
117.
Z. Jánošíková ‐ Hečková E. Ondrušková M. Barta R. Ostrovský M. Kádasi‐Horáková K. Pastirčáková M. Kobza K. Adamčíková 《Forest Pathology》2018,48(3)
The occurrence and distribution of Dothistroma needle blight (DNB) were studied in 2014–2017 around Slovakia. A total of 84 localities, both native and planted, were investigated, and the presence of DNB was confirmed in 73 of them. In all positive locations, symptoms typical of DNB were observed and the Dothistroma species was confirmed using species‐specific primers either from fungal cultures or directly from needles. Both Dothistroma species—D. septosporum and D. pini—were identified. Both species occurred together in 29 locations, only D. septosporum in 42 and only D. pini in two locations. The host range of D. septosporum included 10 pine species and two spruce species. The host range of D. pini comprised the same number of pine hosts but only one spruce species. Five pine hosts, P. aristata, P. coulteri, P. densiflora, P. jeffreyi, P. × schwerinii, and one spruce host P. abies are new hosts species of D. pini. P. densiflora and Picea pungens have earlier been reported to be susceptible for DNB. In this study, D. septosporum was found from both tree species. 相似文献
118.
Biological control of chestnut blight in Croatia: an interaction between host sweet chestnut,its pathogen Cryphonectria parasitica and the biocontrol agent Cryphonectria hypovirus 1 下载免费PDF全文
119.
Retracted: Gonad histology and serum 11‐KT profile during the annual reproductive cycle in sterlet sturgeon adult males,Acipenser ruthenus 下载免费PDF全文
A Golpour C Broquard S Milla H Dadras AR Baloch T Saito M Pšenička 《Reproduction in domestic animals》2017,52(2):319-326
The aim of this study was to assess monthly testicular development in the cultured breeding stock of sterlet, Acipenser ruthenus, using histological and serum sex steroid changes. Testicular development in the adult male was examined monthly and showed four distinct phases including resting, pre‐spawning, spawning and post‐spawning. Also, seasonal changes of the testes were described according to its variations in gonadosomatic index (GSI) during different phases of testicular development. Using histology, we identified continuous spermatogenesis and asynchronous gonad development pattern in the testes of male sterlet, which shows that regulation of annual gonadal cycle is influenced by season. Results also showed variation in the GSI value and number of spermatogenic cells according to each season during annual cycle of gonad, as the highest value of GSI was recorded during spawning phase (spring; March‐May). Hormonal profiles of 11‐ketotestosterone (11‐KT) showed peak, which indicated a seasonal pattern of gonadal development. The 11‐KT concentration increased considerably during the spermatogenesis (pre‐spawning phase) and remained quite high throughout the pre‐spermiation period. In the final phase of testicular development (spawning phase), the 11‐KT markedly dropped. This study undertook an examination of complete reproductive development in cultured sterlet sturgeon to provide a valuable guide for the future sterlet studies, and allows comparison of reproductive development between sturgeon species. 相似文献
120.
Nina Zupančič 《Journal of Soils and Sediments》2017,17(4):1073-1083