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71.
Advanced, multidimensional models are typically applied when researching processes occurring in the nearshore. Relatively simple, empirical equations are commonly used in coastal engineering practice in order to estimate extreme wave run-up on beaches and coastal structures. However, they were mostly calibrated to the characteristics of oceanic coasts, which have different wave regime than a semi-enclosed basin like the Baltic Sea. In this paper we apply the formulas to the Polish Baltic Sea coast. The equations were adjusted to match local conditions in two test sites in Międzyzdroje and Dziwnówek, where beaches are under continuous video surveillance. Data from WAM wave model and coastal gauge stations were used, as well as precise measurements of the beaches'' cross-sections. More than 600 run-up events spanning from June to December 2013 were analysed, including surges causing dune erosion. Extreme wave run-up R2% was calculated and presented as a percentage value indicating what part of the beach was inundated. The method had a root-mean-square error of 6.1 and 6.5 percentage points depending on the test site. We consider it is a fast and computationally undemanding alternative to morphodynamic models. It will constitute a part of the SatBałtyk Operating System-Shores, delivering forecasts of wave run-up on the beaches for the entire Polish coastline. 相似文献
72.
Ewa Hanus-Fajerska Maria Lech Anna Pindel Kazimierz Miczyński 《Acta Physiologiae Plantarum》2000,22(3):317-324
Protocols elaborated with the objective of achieving valuable material for selection procedure of variants with virusresistance
traits in tomato genotypes are presented. Preliminary results are demonstrated in the domain of testing for variability in
somaclones obtained through indirect adventitous organogenesis initiated on leaf explants of cultivated tomato (Lycopersicon esculentum Mill.). Somaclones were grown in greenhouse conditions and variation of their symptoms upon infection with tomato mosaic
(ToMV) or cucumber mosaic (CMV) respectively was observed. Tests for resistance to the local isolates of the above cited viruses
were performed using enzyme linked immunosorbent assay and back inoculation onto diagnostic plants. Screening data are presented.
Desirable variants were selected from cultivars ‘Moneymaker’, ‘Potentat’ and ‘Rutgers’. Some of the ‘Moneymaker’ somaclones
exhibited increased tolerance to cucumber mosaic virus, a few seemed to be even fully resistant though most were susceptible
as donor plants. The most favourable somaclonal lines are actually further tested and monitored for changes in horticultural
characteristics. The described procedure of searching for resistance trait in specific pathogen-free (SPF) plants regenerated
from infected tissue looks promising and thus can serve as aid in attaining appropriate objectives of breeding programme.
Additionaly experiments were initiated to obtain somaclones from cultivars ‘Beta’, ‘Krakus’ and Stevens Rodade hybrid via
regeneration of isolated protoplasts. To this end the callus stage was obtained from all donors. 相似文献
73.
Alma Hortensia Serafín Muoz Kazimierz Wrobel J. Felix Gutierrez Corona Katarzyna Wrobel 《Mycological Research》2007,111(5):626-632
The effect of two inorganic selenium forms has been investigated in the mycelia of Pleurotus ostreatus exposed to cadmium and silver salts in the shaken cultures. The degree of toxicity was assessed by the determination of malondialdehyde (MDA; a common biomarker of lipid peroxidation). The mycelia were exposed to one element form (up to 5 mg l−1) and also to the following combinations: cadmium(II) + selenium(IV); cadmium(II) + selenium(VI); silver(I) + selenium(IV); silver(I) + selenium(VI). The concentrations of cadmium, silver, selenium, and MDA were assessed in the mixed cytosol and cell membrane fractions (CCM). A positive correlation between MDA and cadmium was found in the CCM (β = 0.7775, P = 0.0001), whereas the effect of silver was less significant (β = 0.4642, P = 0.039). These results indicate that silver(I) and cadmium(II) have different capacities to induce lipid peroxidation in P. ostreatus. The protective role of selenium against metal-induced oxidative damage was found to be dependent on the oxidation state of the element form in the growth medium. The strongest beneficial effect was observed in mycelia exposed to cadmium(II) + selenium(IV) (inverse correlation between MDA and selenium in the CCM: β = −0.7129, P = 0.009) and it has been ascribed to a lower incorporation of the toxic metal and/or to possible intracellular interaction between selenium and cadmium. Under exposure to silver(I), the protective effect of selenium(IV) was less noticeable (correlation between MDA and selenium in the CCM; β = −0.6068, P = 0.036); in the presence of selenium(VI), no beneficial effect was observed. 相似文献
74.
Katarzyna Szyba Maria Cieślak Golonka Kazimierz Gasiorowski Joanna Urban 《Biometals》1992,5(3):157-161
Copper(II) chromate and dichromate complexes with 2,2'-bipyridyl and 1,10-phenathroline were tested for their mutagenic activity in the standard Ames test. All of six tested complexes exhibited markedly lower mutagenic activity than the reference compounds--potassium dichromate and sodium chromate. The blockage of Cr(VI) reduction capability in the presence of the complex Cu2+ ion and the competition between copper and chromium ions in the interaction with cellular components are discussed in the light of the results of our previous chemical study. 相似文献
75.
Furmanowa Miroslawa Glowniak Kazimierz Syklowska-Baranek Katarzyna Zgórka Grazyna Józefczyk Aleksandra 《Plant Cell, Tissue and Organ Culture》1997,49(1):75-79
We have analysed the effect of some culture conditions and media components on callus growth rate and production of taxanes
in callus of Taxus × media var. Hatfieldii. For callus induction and maintenance a Gamborg B5 medium and a White - Rangaswamy
medium (WR) with different modifications were used. On an improved WR medium (containing 10 μM picloram) the callus growth
factor increased up to 5.8 fold (fresh weight). Picloram only enhanced the growth of callus, but not taxane production. On
WR medium with (100 μM) methyl jasmonate the paclitaxel content increased from 2.37 μg g-1 to 90 μg g-1 and cephalomannine
from 5.14 μg g-1 to 29.14 μg g-1 (dry weight), whereas growth of the cultures ceased. The presence of paclitaxel and cephalomannine
was established by high performance liquid chromatography.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
76.
Cellular subsets of the milky spots in the human greater omentum 总被引:11,自引:0,他引:11
Masataka Shimotsuma Toshio Takahashi Mitsuhiro Kawata Kazimierz Dux 《Cell and tissue research》1991,264(3):599-601
Summary The cellular composition of the human milky spots was investigated on surgically removed specimens of the greater omentum of three 8-month-old infants operated on for neuroblastoma. Monoclonal antibodies and immunohistochemical methods for recognition of macrophages, B-lymphocytes and T-lymphocytes and toluidine-blue staining for mast cells were used. The mean number of cells in one milky spot amounted to 570±33. This cell population was composed of 47.5% macrophages, 29.1% B-lymphocytes, 11.7% T-lymphocytes and 6.1% mast cells. Since inflammation was absent in the material investigated, the numerical data found in the present paper could be regarded as representative cell levels of normal milky spots. 相似文献
77.
Kazimierz Browicz 《Plant Systematics and Evolution》1987,155(1-4):189-195
The author discusses the history of an unusual form ofPistacia lentiscus L. (referred to as var.chia (Desf. exPoiret) DC. on the basis of literature data and personal field observations on Chios island. As a result of incisions made on the trunk and stems the tree exudes a specific resinous gum called mastic. The production of mastic currently amounts to 160–170 tons per annum and plays an important role in the economy of the island constituting the main source of income for approx. 20 villages in the south of Chios. The history of mastic dates back 2500 years to the time ofHerodotus. The author points out that on the plantation only male individuals are cultivated; these have been selected over a long period based on mastic yield. As they represent a group of cultivated clones it would be preferable to consider them as a collective cultivar Chia. 相似文献
78.
An isolated guinea-pig ileum preparation was used to screen for bioactive compounds from algae. 212 culture supernatants and methanolic extracts of randomly chosen marine and freshwater algae were tested for their effect on electrically evoked muscle contractions (recorded as a change in tension) and on the resting muscle tone. 15 out of 42 (35%) of the marine algae tested and 5 out of 64 (8%) of freshwater algae gave positive results. Of the 20 algae giving positive results, 6 had previously been shown to produce bioactive compounds (mainly toxins) but we can find no reports in the literature of bioactive compounds from the remaining 14. Of these 14 cultures, 9 were axenic and therefore production of the biological activity can be assigned unambiguously to the alga. These results confirm the usefulness of the guinea-pig ileum preparation as a screen for bioactive compounds from microbial cultures. 相似文献
79.
80.
Kazimierz Ostrowski 《The Histochemical journal》1972,4(5):467-476
Synopsis The principles of a histoenzymological method based on the use of labelled inhibitors are reviewed. The detection of inhibitor-labelled enzyme complexes by histoautoradiography allows enzymes to be localized quantitatively in cells and tissue structures. The present state and future possibilities of the method are discussed.This review was presented in a shorter form at the International Symposium on Autoradiography organized by the Royal Microscopical Society at Nottingham in July 1971. 相似文献