28 research outputs found
The activity of hydrolytic enzymes in the digestive system of Acanthobdellida, Branchiobdellida and Hirudinida (Annelida,Clitellata) – considerations on similarity and phylogeny
Activities of nineteen hydrolases were measured in the digestive systems of predatory and blood-feeding true leeches (Hirudinida) and their closest relatives, Branchiobdellida and Acanthobdellida. Hydrolase activities were analyzed in different parts of the digestive systems: the species-specific anterior part, i.e. jaws, pharynx or proboscis, crop and intestine. The results obtained suggest that food digestion and possible absorption predominate in the intestine of most of the studied Hirudinida and A. peledina, whereas in B. astaci these processes take place in the anterior part of the digestive system and crop. In Erpobdellidae and Piscicola respirans, the activity of acid and alkaline phosphatases, N-acetyl-β-glucosaminidase, leucine and valine arylamidases, and α-fucosidase was also detected in the anterior part of the digestive system. We also detected differences in enzyme occurrence between the studied species, which are probably connected with their different food preferences. Moreover, the presence of the whole spectrum of enzymes in predatory leeches and the absence of trypsin and α-chymotrypsin activity in the crop of all the leeches support the hypothesis that the leech ancestor was a blood-feeder. Our study showed that “Rhynchobdellida” constitute a paraphyletic group which confirms the previous results based on molecular phylogenetics, while Arhynchobdellida appears to be a non-monophyletic group which is not consistent with previous molecular results
Hamas wobec sporu palestyńsko-izraelskiego. Między procesem pokojowym a eskalacją konfliktu
Hamas to the Palestinian-Israeli dispute. Between the peace process and the escalation of the conflictIssues around which the focus is at stake, for the ongoing Holy Land in the Israeli–Palestinian conflict and its impact on the Islamic Resistance Movement. The dispute, which still has not found a solution took on the character of the war of civilization of Islam and the West. Significantly expanded its boundaries and is not just a conflict over land, but the conflict unfolding on several levels – military, ethnic and religious controversy, which engage in other countries recognizing the danger of its further escalation. This article aims to analyze the role of Hamas in the disputed territories, its origins, the links ideological organizational structure. The starting point for the delineation of the relationship is to present contemporary political events and the analysis of stereotypes and misconceptions, chich became the basis of mutual aversion two years warring sides in the conflict.</p
Nowoczesność a tradycja pod polskimi torami
Wywiad z mgr. inż. Robertem Strużyńskim z Hobas System Polska Sp. z o.o
Przepust kolejowy z rur z żywic poliestrowych CC-GRP HOBAS
6 marca 2009 r. w siedzibie Oddziału Regionalnego PKP PLK SA we Wrocławiu odbyło się podpisanie umowy Odbudowa i modernizacja linii kolejowej E 30/ CE 30 na odcinku Opole Wrocław - Legnica, szlak Środa Śląska - Malczyce tor 1 i 2 wraz ze stacją Malczyce. Generalnym wykonawcą robót jest konsorcjum w składzie: Przedsiębiorstwo Robót Kolejowych o Inżynieryjnych SA (lider), Przedsiębiorstwo Budownictwa Kolejowego i Inżynieryjnego INFRAKOL SC oraz Przedsiębiorstwo Robót Komunikacyjnych w Krakowie SA. Wartość umowy wynosi 167 221 315 zł netto. Termin realizacji umowy wynosi 18 miesięcy od daty jej podpisania
REVIEW OF THE NATIONAL RESTOCKING PROGRAMME “ACTIVE PROTECTION OF NATIVE CRAYFISH IN POLAND” 1999-2001
After the first spread of crayfish plague (aphanomycosis) at the end of the nineteenth century, the formerly abundant populations of native crayfish in Poland declined drastically. Analysis of historical data on the occurrence and distribution of crayfish in Poland led to the conclusion that without human intervention the native crayfish species would be at high risk of being made extinct. The largest programme concerning crayfish monitoring and restocking in Poland was “Active protection of native crayfish in Poland” conducted by the Inland Fisheries Institute, the Department of Ecology, University of Szczecin, the Department of Zoology, Warsaw Agricultural University and the University of Warmia and Mazury that was funded by the EkoFundusz Foundation and Inland Fisheries Institute in 1999-2001. One of the main objectives and results of this programme was the determination of indigenous crayfish distribution in Poland (mainly Astacus astacus and Astacus leptodactylus) and the restocking of suitable habitats with indigenous crayfish.
The densest populations (> 2 500 adult individuals per hectare) were used as a source of restocking material. Restocking was performed in 54 water bodies using a total of 45 200 individuals of A. astacus and 9 800 of A. leptodactylus. Between 2001-2002, the success of the restocking programme was monitored. According to the results obtained so far, the restocking exercise has been successful in at least 60.8% of the cases
New records of the invasive red swamp crayfish
This contribution presents new observations of the red swamp crayfish, Procambarus clarkii in Poland. The species was detected in Żerań Canal and Krasiński Garden in Warsaw (central Poland) where 5 and 2 individuals were collected respectively as well as in Dąbie Pond in Krakow (southern Poland) with total of 4 crayfish observed. These new sites are located approximately 500 km eastward (Warsaw) and 240–260 km northward (Krakow) from the nearest European sites where this species has been previously recognised (near Berlin, Germany, Egerszalók and Budapest, Hungary), thus are the furthest north-east records of the species in European open waters. It is likely that the examined stock originates from single introductions, however, presence of the juveniles caught in Warsaw suggests that the population found there may be breeding. The findings are discussed with available literature describing possible ways P. clarkii may use to colonize new habitats as well as the impact it has on the invaded ecosystems in general and native crayfish in particular
Monthly changes in physicochemical parameters of the groundwater in Nida valley, Poland (case study)
The groundwater of the Nida valley was investigated to assess the quality of water source and monthly variations of the physicochemical parameters. A total of 70 water samples were collected from 7 sampling sites during a 10 months period from June 2021 to March 2022. Sampling frequency was once per month. The parameters such as temperature (T), electrical conductivity (EC), dissolved oxygen (DO), pH, total dissolved solids (TDS) were measured in-situ by using handheld device. Meanwhile, total nitrogen (TN), total phosphorus (TP), chloride (Cl – ), sulphate (SO42– ), manganese (Mn), iron (Fe), zinc (Zn), cadmium (Cd), lead (Pb), copper (Cu), chemical oxygen demand (COD) were analysed in the laboratory. According to the classification of Ministry of Marine Economy and Inland Navigation in Poland (2019), some investigated parameters are classified as unsatisfactory quality waters (class 4) and poor-quality waters (class 5) for a few specific months. Such as, TP concentrations obtained in June and January are classified as class 4, SO42– concentrations corresponded to classes 4 and 5 in June, July and August, and Mn concentrations (except in January) are settled in class 5. The high values of Fe in November are arranged in class 5 and in June, July to September and March are classified in class 4. Statistical methods were used as: Shapiro-Wilk test (α = 0.05), ANOVA test and post-hoc Tukey test (α = 0.05), Kruskal-Wallis test and Wilcoxon (Mann-Whitney) rank sum test (α = 0.05) estimated the significant differences in sampling months. Pearson correlation analysis (α = 0.01 and 0.05), principal component analysis (PCA) and cluster analysis showed correlation between the parameters and sampling months
Interaction of surface water and groundwater in Nida valley, Poland
The study area of the Nida valley was examined to investigate variations in groundwater and surface water levels, as well as the interaction between them. In the valley, there were three branches. The two actives were the Nida River itself and the Smuga Umianowicka branch while the Stara Nida branch was dry during the measurement session. Over a 12-month period from June 2021 to June 2022, 7 monitoring points were equipped with piezometers, comprising 5 groundwater points and 2 surface water points. The monitoring frequency was set to 30 minutes. The results of this research indicate that there are significant differences in the water level at the same observed point at different times. This study demonstrates seasonal changes in both surface water and groundwater levels with higher levels in autumn and winter and lower levels in spring and summer, which are closely tied to the changes in meteorological conditions during the research period, such as precipitation and air temperature. The study results also indicate that during summer and winter at the Nida River and its riparian area, losing stream is the primary process occurring in the studied reach. Conversely, during autumn and spring, the main process is gaining stream. At the human-maintained Smuga Umianowicka branch and in its riparian area, losing stream is the main process during summer and autumn, and gaining stream is the main process during spring. During winter, losing stream and gaining stream processes can occur simultaneously, and neither process takes place mainly