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Praca przedstawia faunę pająków zasiedlających zadrzewienia śródpolne kępowe i pasowe oraz miedze. Celem pracy jest zaprezentowanie tych środowisk jako ostoi gatunków pająków rzadkich i zagrożonych w Polsce. Badaniami objęto cztery zadrzewienia i dwie miedze na Nizinie Południowopodlaskiej w latach 1998–2000 oraz cztery zadrzewienia w Wielkopolsce w okresie dwóch miesięcy (kwiecień i maj) 2007 roku. Próby pobierano za pomocą pułapek Barbera oraz czerpaka entomologicznego. W badanych siedliskach stwierdzono siedem gatunków pająków narażonych na wyginięcie według Czerwonej listy zwierząt ginących i zagrożonych w Polsce, oraz 14 gatunków rzadziej stwierdzanych. Większość zagrożonych gatunków odnotowano w zadrzewieniach śródpolnych: Ero cambridgei, Xysticus luctator, Marpissa radiata, Thanatus arenarius, natomiast na miedzach występowały: Porrhomma errans, Porrhomma microphthalmum oraz Clubiona diversa. Zarówno wymienione gatunki pająków, jak i rzadziej stwierdzane taksony związane są ze środowiskami mniej lub bardziej wilgotnymi. Należy dążyć do zachowania w krajobrazie rolniczym zbiorników i cieków wodnych oraz miedz i zadrzewień jako refugiów zwiększających poziom bioróżnorodności
The impact of wooded shelterbelts on the patrolling intensity (number of patrolling individuals per trap, per day (NP) – activity density) of spiders and ground beetles was investigated by using pitfall traps placed in parallel rows in shelterbelt centers, along margins of wood and field, and in open wheat fields at a distance of 10 and 50 m from trees. In the shelterbelt – managed areas the biomass of patrolling (BP) arthropods (ground beetles and spiders) was lower inside the fields (F₁₀, F₅₀) than at the field margins and in the shelterbelts. The BP and individual weight increased with the age of strips. However, in the control field with no wood in the vicinity, the BP of carabid beetles was as high as inside the shelterbelts. The highest similarity between the shelterbelts and the field (BP, Morisita’s similarity index, diversity index H’, individual weight) was found in the field adjoining the youngest (aged 2 years) shelterbelt. It is concluded that similarity between permanent and cultivated ecosystems is important for successful exchange of individuals between them. In the field adjacent to young shelterbelt and in the field with no woods in the vicinity the aeronautic, agrobiont species prevail. In the fields adjacent to older shelterbelts colonization by large body-size species, characteristic for permanent ecosystems was found.
The study was carried out on lowland agricultural lands in western Poland between July and August 2007. The influence of the proximity of forested areas on the occurrence of foliage-dwelling spiders was defined by measuring the abundance of spider webs on five transects situated at distances of 0, 20, 40, 60 and 80 metres from the forest edge. Generally, the greatest diversity and the highest total density were observed close to the forest edge, but an opposite relation was found for orb webs, built by spiders from the families Araneidae and Tetragnathidae, whose abundance was the lowest in close proximity to the forest. At a distance of 80 metres from the forest a slight increase in total abundance of webs was recorded, no doubt due to the presence of weeds, in which were recorded numerous occurrences of sheet and irregular webs. On all the transects studied, orb webs predominated on maize shoots, whereas only three-dimensional sheet and irregular webs occurred on weeds. Included in this discussion are some of the potential effects of the proximity of forest areas on foliage-dwelling spider populations in maize fields and on the possibilities for spiders limiting this crop’s pests.
The purpose of this study has been to determine the quantitative and qualitative composition of spiders captured on winter wheat plantations. In 2008–2009, observations were carried out in north-eastern Poland, in the village Bartążek near Olsztyn (UMT DE 65). Spiders were caught every 7 days, from April to August, with a sweep net. One sample consisted of 100 beats with the sweep net at the height of the herbaceous plants. As a result, 245 spiders classified into 10 families, 29 genera and 30 species were caught on winter wheat plantations. The most numerous families were Araneidae, Linyphiidae, Tetragnathidae, Theridiidae and Thomisidae. The most numerous species were Mangora acalypha, Aculepeira ceropegia, Erigone atra and Tetragnatha pinicola. A special emphasis should be pay on the presence of Nusoncus nasutus a species of the family Linyphiidae, which is rare in Poland and currently listed on the Red List of Threatened and Endangered Species.
In recent years, a massive effort has been directed towards designing potent and selective antagonists of neurohypophyseal hormones substituted at position 3. Modi­fication of vasopressin at position 3 with 4,4'-biphenylalanine results in pharmaco­logically inactive analogues. Chemically, this substitution appears to vary only slightly from those previously made by us (1-Nal or 2-Nal), which afforded potent agonists of V2 receptors. In this situation, it seemed worthwhile to study the struc­ture of the analogues with 4,4-biphenylalanine (BPhe) at position 3 in aqueous solu­tion using NMR spectroscopy and total conformational analysis. This contribution is part of extensive studies aimed at understanding spatial structures of 3-substituted [Arg8 ]vasopressin analogues of different pharmacological properties. NMR data were used to calculate 3D structures for all the analogues using two methods, EDMC with the ECEPP/3 force field, and molecular dynamic with the simulated annealing (SA) algorithm. The structures obtained by the first method show a better fit between the NMR spectral evidence and the calculation for all the peptides.
 Six hybrid N-ureidoethylamides of octapeptides in which an N-terminal cyclic structure related to enkephalin was elongated by a C-terminal fragment of deltorphin were synthesized on MBHA resin. The synthetic procedure involved deprotection of Boc groups with HCl/dioxane and cleavage of the peptide resin with 45 % TFA in DCM. d-Lys and d-Orn were incorporated in position 2, and Lys, Orn, Dab, or Dap in position 5. The side chains of the dibasic amino function were protected with the Fmoc group. This protection was removed by treatment with 55 % piperidine in DMF, and cyclization was achieved by treatment with bis-(4-nitrophenyl)carbonate. Using various combinations of dibasic amino acids, peptides containing a 17-, 18-, 19- or 20-membered ring structure were obtained. The peptides were tested in the guinea-pig ileum (GPI) and mouse vas deferens (MVD) assays. Diverse opioid activities were observed, depending on the size of the ring. Extension of the enkephalin sequence at the C-terminus by a deltorphin fragment resulted in a change of receptor selectivity in favor of the δ receptor. The conformational propensities of selected peptides were determined using the EDMC method in conjunction with data derived from NMR experiments carried out in water. This approach allowed proper examination of the dynamical behavior of these small peptides. The results were compared with those obtained earlier with corresponding N-(ureidoethyl)pentapeptide amides.
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