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Open access

Piotr Zieliński and Tomasz Suchowolec

Abstract

Five parallel channels of the Narew River (NE Poland) were hydromorphologically assessed with the River Habitat Survey (RHS) method. Four out of the five studied channels were partly separated from the functioning system of the anastomosing river by a dike for more than 20 years, and were subjected to gradual overgrowing and shallowing. In the 1990’s and in 2002, a number of renaturisation measures were implemented, restoring sufficient discharge for the channels to make them active again. The Habitat Modification Score (HMS) obtained as a result of the survey only classifies the fragment ecologically to the third class of streams with high HMS value in the case of the current main channel of the Narew River (largely formed in an artificial manner). This suggests substantial anthropogenic changes in the river channel and its vicinity. The aggregate values of the Habitat Quality Assessment (HQA) index suggest the preservation of numerous environmentally valuable elements at all of the five studied sites of the anastomosing Narew River system. This even concerns channels which remained almost separated and functioned as oxbow lakes for more than 20 years. The highest HQA values were recorded in the case of the channel constituting the main channel before the regulation, and a neighbouring regulated channel currently fulfilling the function of the main water course in this cross-section. In spite of long-term negative changes, the studied fragment of the ecosystem of the anastomosing river is distinguished by high resistance to “anthropogenic stress”, and high capacity for spontaneous restoration of a state close to the natural one. Although lotic ecosystems constitute elements of the natural environment particularly sensitive to anthropopressure, they retain the ability to regenerate for a long time, under the condition of providing them with relevant hydrological and ecological conditions.

Open access

Monika Zielińska, Piotr Zieliński and Tomasz Mokwa

Juvenile Blackbird (Turdus merula) moulting primaries and secondaries

Open access

Ewa Zieliński, Kinga Grobelska, Piotr Dzięgielewski and Romuald Olszański

Abstract

This paper presents a case report of a patient with a diagnosed complication of a sternum wound which was treated using hyperbaric oxygen, emphasizing the truism of the benefits of combined surgical therapy, antibiotic therapy and oxybarotherapy.

Open access

Danuta Drzymulska and Piotr Zieliński

Abstract

Our study concerns the development of marginal zone of Lake Suchar Wielki (Wigry National Park). This humic lake is characterised by mire occurrence in its marginal zone, covered with a floating mat spreading on water surface. Biogenic sediments (peat archive) present in lakeside allow recognising the thousands years’ development pattern of lake surrounded by mire. The wetland records were analysed for plant macroremains, degree of peat decomposition, sediment geochemical features along with age assessment. Morphological characteristics of the catchment were integrated with the wetland records. Our research showed that after the lake origin in the Allerod, accumulation in its marginal zone was interrupted, which was probably connected with high precipitation in the past. Slope processes could be possible. Stabilisation of environmental conditions took place in the younger Holocene. Despite these perturbations marginal zone of the lake was permanently terrestrial in character, as indicated by values of atomic C:N ratio.

Open access

Adam Cudowski and Piotr Zieliński

Abstract

Hydrochemical investigations focusing on different iron fractions were conducted in 2007 from January to December on two parts (regulated and restored) of the small lowland Rudnia River in north-eastern Poland. Concentrations of the total iron (TFe) in the water of the Rudnia River ranged from 582 μg dm-3 up to 3646 μg dm-3, and their elevated values are clearly the result of their complex binding with organic matter originating from the peat-mineral catchment of the river. Regardless of the season, in the upper part of the river (regulated channel) higher concentrations of all iron fractions than in the restored river section were observed. All tests on iron fractions showed a clear seasonal variability on both river channel parts. Higher TFe concentrations were typical for the regulated part of the river in autumn or winter, and lower in spring for the restored river channel section. For the whole of the investigated period and regardless of the season, particulate iron fraction (PFe) represented a higher proportion of TFe in the regulated channel than in the restored one. PFe constituted up to 60% TFe, on average, while the other two fractions about 20% of TFe each. However, dissolved reactive iron fraction (DRFe) made up a larger percentage of TFe than organic soluble fraction (DOFe) of iron within the year. The maximum percentage of DOFe fraction outside the growing season was caused by iron release from organic complexes and elevated concentrations of dissolved organic carbon (DOC) derived from wetlands.

Open access

Michał Kowal, Sławomir Kubal, Piotr Piotrowski and Ryszard Zieliński

A Simulation Model of the Radio Frequency MIMO-OFDM System

The paper presents a simulation model of the radio frequency MIMO-OFDM system. The simulation model was made in Matlab Simulink environment. It contains the transmitter, the receiver and the telecommunication channel models. The telecommunication channel model consists of models used during development of technical documentation of IEEE 802.11n. Signals generated at the transmitter output are fully compatible with signals described in IEEE 802.11n [1]. Simulations are conducted on a radio frequency, so they can be compared with results of measurements of real systems.

Open access

Michał Kowal, Sławomir Kubal, Piotr Piotrowski and Ryszard Zieliński

Operational characteristic of wireless WiMax and IEEE 802.11x systems in underground mine environments

The paper presents research results pertaining to transmission parameters of wireless communication systems, based on WiMax and IEEE 802.11x radio interfaces. Research was performed in severe operating conditions of an underground mine - testing various parameters, such as: throughput, delays and maximum range.

Open access

Ewa Zieliński, Anna Lipińska, Kinga Grobelska and Piotr Siermontowski

Abstract

This article presents a description of a case of a patient diagnosed with complicated inflammation of the tibia bone, who was treated hyperbarically, in order to underline the advantages of this method of treatment used not as an alternative to antibiotics and surgery, but as a supportive method.

Open access

Jolanta Ejsmont-Karabin and Piotr Zieliński

Abstract

Studies were carried out in September 2007 at a set of stations called RIVERS located on two tributaries of the Narew River, and six stations on the tributaries of the Supraśl River. Concurrently, rotifers were sampled at nine stations of the River Rudnia (called RUDNIA). The aim of the research was the verification of the hypothesis on the uniforming effect of the river drift on rotifer communities inhabiting aquatic vegetation. The total numbers of all monogonont species inhabiting aquatic vegetation of RUDNIA and RIVERS were 83 and 107, respectively. The percentage similarity of rotifer communities from aquatic vegetation and river current at the same stations was relatively low and only slightly higher in RIVERS (21.7%) than RUDNIA (17.1%), which suggests that species composition of communities of epiphytic rotifer fauna has a rather low impact on species structure of rotifer communities in water drift. The set of individuals of different species carried with the water current was random and various at different stations. Although the percentage similarity of rotifer communities in the river drift calculated for all possible pairs of the stations was relatively lower in RIVERS than in RUDNIA, it was not reflected in the similarity of epiphytic rotifer communities, which were similar in both sets of stations. Thus, the hypothesis cannot be confirmed by the results of this research.

Open access

Tomasz Zieliński, Piotr Czyżewski and Marek Szczepkowski

Abstract

The operation to restore the continuity of the gastrointestinal tract is another surgical intervention in a given patient, which directly translates into an increased risk of complications during and after surgery. That is why proper qualification is important for the operation to restore the continuity of the gastrointestinal tract in terms of performance and efficiency of the anal sphincter apparatus, among other things.

The aim of the study was to evaluate the effect of restoring physiological defecation routes on the sphincter function and to observe the parameters of anorectal manometry in patients before and after surgery to restore the continuity of the gastrointestinal tract.

Material and methods. The study included 29 patients scheduled for restoration of the continuity of the gastrointestinal tract, 12 women and 17 men. The average age in the group was 62 years. Anorectal manometry was performed both before surgery as well as one month and three months afterwards in all patients. The average time to have a stoma was 12 months.

Results. The resting pressure in the anal canal (MRP) three months after the restoration of the continuity of the gastrointestinal tract increased by 30.4%. The maximum systolic blood pressure in the anal canal (MSP) increased by 22.2%. The value of recto-anal inhibitory reflex (RAIR) decreased by 19.2%. The length of the high pressure zone in the anal canal (HPZL) increased by 27%. The study results of visceral rectal sensation thresholds decreased by 23.3% for the sensation threshold, and 14.4% for the pressure threshold.

Conclusions. Restoring the continuity of the gastrointestinal tract improves the anal sphincter function which is evident in the parameters of anorectal manometry. The restoration of passage improves the sphincter function, and these changes are statistically significant.