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The aim of the work was to describe the variability of a group of meiobenthos inhabiting a tidal flat in Nottinghambukta which is influenced by the diverse conditions of a seasonal as well as multi-annual cyclicity. Samples were collected in five series, i.e. during the Arctic spring (2001), summer (2000 and 2001) and autumn (2001). The material for qualitative analysis was collected from sites with different hydrological characteristics. The following major meiobenthic taxa were found: Metazoa, i.e. Nematoda and Crustacea (Ostracoda and Copepoda-Harpacticoida), and Foraminifera. Unstable conditions in the bay result in a seasonal variability in the species composition as well as an uneven colonisation of the Nottinghambukta area by meiobenthos. The lowest taxonomic diversity occurs in summer, but it increases in autumn when the land runoff ceases. Based on the conducted analysis, it can be concluded that the inflow of seawater in autumn brings on the occurrence of new taxa, which probably inhabit the bay temporarily until the summer season during which the highly variable conditions cause a change in the species composition. For the series of samples collected in July 2000 and 2001, the species composition for Harpacticoida was determined. The taxonomic diversity of the harpacticoid assemblage inhabiting the bay was observed in the two subsequent years. Moreover, during the study duration a considerable decrease was observed in the abundance of Ostracoda in Nottinghambukta.

Maximum depth of colonization (zC) and total area covered by a population of Lobelia dortmanna, as well as underwater light regime were studied in 25 soft water lobelia lakes in north-western Poland. Variations in underwater light conditions among the lakes were described by Secchi disc depths (zSD), and by attenuation coefficients of irradiance within photosynthetically active radiation range (Kd,PAR), and euphotic zone depths (zEU) derived from photometric measurements conducted twice a year (in midspring and midsummer) during the period 2014–2015. Maximum depth of colonization of water lobelia ranged from 0.1 to 2.2 m (median zC = 0.8 m; mean zC = 1.0 m). Nine lakes showed the relative coverage of the littoral zone (RCLZ) by L. dortmanna to be greater than the mean value, which was 4.8%. Studies showed that light requirements of water lobelia increase when the maximum depth of colonization also increases. This pattern could be partially related to the greater energy needs of deeper growing individuals due to enlarged seed production and their incubation, and for the creation of much heavier inflorescences. Assessment of the light requirements of L. dortmanna along the depth gradient indicates that relative irradiance (percentage of subsurface irradiance of PAR) should be at the level of: (i) 47–50% (annual total of quantum irradiance 3083–3280 mol m−2 yr−2) for plants growing within a depth range of 2.0–2.5 m; (ii) 44–47% (2886–3083 mol m−2yr−1) for plants growing within a depth range of 1.5–2.0 m; (iii) 41–44% (2690–2886 mol m−2yr−2) for plants growing within a depth range of 1.0–1.5 m; and (iv) 34–41% (2230–2690 mol m−1 yr−1) for those growing in the littoral zone at a depth of between 0.5 and 1.0 m. In average conditions in the Pomeranian lakes, the maximum depth of colonization by L. dortmanna accounts for approximately a third of the Secchi disc depth and a fifth of the depth of the euphotic zone with irradiance of PAR at zC equal to about 43% of subsurface irradiance. It has also been demonstrated that the light factor is a crucial one that limits the absolute maximum depth of lobelia population occurrence in Pomeranian lakes. The cleanest and most transparent lakes of this region have light attenuation coefficients (Kd,PAR) within the range of 0.35–0.42 m−1, which corresponds to the maximum colonization depths of 1.8–2.2 m.

The specific activity of natural gamma emitters like actinium (228Ac), bismuth (212Bi, 214Bi), lead (212Pb, 214Pb), potassium (40K), radium (224Ra), thallium (208Tl) and artificial radioisotope caesium (137Cs) was measured in 2005 in the surface layer of marine sediments in the northern Svalbard: Wijdefjorden, Woodfjorden, Vestfjorden and Bockfjorden as well as in the freshwater reservoirs in Andre Land. Nonuniform spatial distribution of these radionuclides was found. Sediment sample from Bockfjorden had the highest specific activities of all natural radionuclides. The specific radioactivity of 137Cs was much lower than specific radioactivities of natural radionuclides but there were differences between investigated locations. The distribution of 137Cs is similar to persistent organic pollutants of the lake sediments in the area.

The results of the latest bathymetric survey of 21 lakes in the Suwałki Landscape Park (SLP) are presented here. Measurements of the underwater lake topography were carried out in the years 2012–2013 using the hydroacoustic method (sonar Lawrence 480M). In the case of four lakes (Błędne, Pogorzałek, Purwin, Wodziłki) this was the first time a bathymetric survey had been performed. Field material was used to prepare bathymetric maps, which were then used for calculating the basic size and shape parameters of the lake basins. The results of the studies are shown against the nearly 90 year history of bathymetric surveying of the SLP lakes. In the light of the current measurements, the total area of the SLP lakes is over 634 hm2 and its limnic ratio is 10%. Lake water resources in the park were estimated at 143 037.1 dam3. This value corresponds to a retention index of 2257 mm. In addition, studies have shown that the previous morphometric data are not very accurate. The relative differences in the lake surface areas ranged from –14.1 to 9.1%, and in the case of volume – from –32.2 to 35.3%. The greatest differences in the volume, expressed in absolute values, were found in the largest SLP lakes: Hańcza (1716.1 dam3), Szurpiły (1282.0 dam3), Jaczno (816.4 dam3), Perty (427.1 dam3), Jegłówek (391.2 dam3) and Kojle (286.2 dam3). The smallest disparities were observed with respect to the data obtained by the IRS (Inland Fisheries Institute in Olsztyn). The IMGW (Institute of Meteorology and Water Management) bathymetric measurements were affected by some significant errors, and morphometric parameters determined on their basis are only approximate.

The article presents the results of experimental research on evapotranspiration and transpiration of a common reed bed. The study was conducted in 2014–2015 on Lake Raduńskie Górne (Kashubian Lakeland) in the summer half-year from 1 May to 31 October. In the experiment two sets of standard evaporimeters GGI-3000 were used. One of the evaporimeters was filled with water, while the second additionally contained common reed. During the experiment medium reed bed density was 240 shoots per square metre. The results of the study showed that during the research period the average daily common reed transpiration was 3.9 mm, and the daily maxima reached 12.1–12.5 mm. Average monthly transpiration totals ranged from 42.8 (October) to 208.5 mm (August). During the growing season, the loss of water to transpiration reached 872–971 mm. The average transpiration rate, determined in the conditions of already well developed reed bed (June-September), was 1.83 dm3 m−2 d−1. The values of the ratios Th/EO and ETh/EO, determined during the experiment, were within the ranges reported in most previous research. The average ratio Th/EO was 1.6, and the ratio ETh/EO was 2.0. These values indicate that during the vegetation period common reed transpiration is higher by 60% from open water evaporation, and the total water losses from the common reed bed to evapotranspiration are twice as high as water loss in open water evaporation.

The shrinking of the Aral Sea represents one of the greatest ecological disasters of modern time. The data on the surviving northern part (Small Aral) is scarce and requires an update. This study aimed to analyze the chemistry, phyto- and zooplankton composition, and their relation in the waters of the Small Aral and its tributary, Syr Darya River. The chemistry of both ecosystems was significantly different. Small Aral was characterized by higher ionic concentrations, salinity, and electric conductivity and more significant spatial variation of chemical properties. The area near the river mouth was more pristine, while the ions concentration and salinity in the distant bays were much higher (>10‰). The highest concentrations of nitrates and total phosphorus in the Syr Darya were observed near Kyzylorda, indicating urban pollution. Overall, 109 phytoplankton taxa were identified in both ecosystems, with diatoms, green algae, and cyanobacteria being most abundantly represented. Oligohalobes dominated, but no polyhalobes and euhalobes algal species were identified. In total, 27 taxa of zooplankton were identified in both studied ecosystems, with the domination of rotifers over microcrustaceans. An exceptionally high level of dominance (65-91%) of rotifer Keratella cochlearis in the Syr Darya was found. The phyto- and zooplankton species richness was higher in the Syr Darya. Plankton communities of the Small Aral reflected horizontal variability of chemical properties. The total phosphorus promoted the prevalence of diatoms, rotifers, and crustaceans. Increased nitrogen concentration promoted cyanobacteria, chlorophytes, cryptophytes and chrysophytes, and rotifers Keratella cochlearis and K. quadrata. The abundance of dinophytes, diatoms Navicula cryptotenella and Cocconeis placentula, green algae Mychonastes jurisii and rotifer Keratella tecta was driven by the higher alkalinity and conductivity/salinity levels. The results represent a reference point for future monitoring of the area and add to understanding the complexity of biological transformations in the Aral Sea and its tributary., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Over recent decades the Aral Sea has faced a major human-driven regression leading to environmental, economic and health impacts. Previous research has indicated that its region may be highly polluted yet there is little recent data to assess the scale or nature of the pollution. The present study investigated the concentration of elements for which the World Health Organization (WHO) has established guideline levels (Al, As, B, Ba, Cd, Cr, Cu, Ni, Pb, Sb) as well as 16 rare-earth elements (Ce, Eu, Er, Gd, La, Nd, Pr, Sc, Sm, Dy, Ho, Lu, Tb, Tm, Y, Yb) in the Small Aral Sea (SAS) and its inflow, the Syr Darya River (SDR). The latter displayed increased levels of Al (mean 851 μg L -1 ), As (35.8 μg L -1 ), Cd (2.8 μg L -1 ), Pb (10.1 μg L -1 ) and U (4.9 μg L -1 ), exceeding the guideline limits at selected sites. In the SAS these limits were exceeded at certain locations in the case of As and U. The total mean concentration of REEs in the SDR and SAS amounted to 22.6 and 61.7 μg L -1 , respectively, with Pr, Ce and Nd constituting the greatest share. The concentrations of B, Ba Cr, Cu, Se and Ni were below the WHO guideline levels at all studied sites while Sb and Hg were always below detection limits. This research provides an updated status on the levels of contamination of the surface waters in the ecological disaster zone of the Aral Sea in Kazakhstan., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The authors would like to correct the error in the "Abstract" section of original publication. The correct sentence should read "The sampled waters were highly acidic (pH 2.1-4.9) and had high electrical conductivity (2.80-15.61 mS cm- 1 ).

A method was developed for the computerized volumetric assessment of the intracranial cerebrospinal fluid (CSF) distribution. The study involved 62 patients differentiated into two groups: with CSF resorption disorders (normal pressure hydrocephalus - 30 patients) and without CSF resorption disorders (various types of brain atrophy - 32 patients). The goal of the study was to ascertain whether the assessment, depending on the linear discriminant analysis of volumetric brain features, could be an effective tool differentiating the two groups. Volumetric measurements were performed using VisNow software. For each patient, five features were determined and subjected to discriminant analysis: CSF volume in the subarachnoid space and basal cisterns (SV), CSF volume in the intracranial ventricular system (VV), brain volume (BV), total intracranial CSF volume (FV), and total intracranial volume (TV). Discriminant analysis enables the achievement of a high percentage of correct classification of patients to the appropriate group determined on the result of a lumbar infusion test. The discriminator, based on three features: BV, SV, and VV, showed a complete separation of the groups; irrespective of age. The squared Mahalanobis distance was 70.8. The results confirmed the applicability of the volumetric method. Discriminant analysis seems a useful tool leading to the acquisition of a computer-aided method for the differential diagnosis of CSF resorption disorders.

Copper mining generates large quantities of waste, tailings, and acid outflows causing long-term environmental impacts and potential threats to human health. Valea Şesei is the largest tailing impoundment in Romania, created by flooding the valley (known as Valea Şesei) of the Metalliferous Mountains (a division of the Apuseni Mountains) with copper mining waste. The present study (i) estimated the total volume of tailings in this area; (ii) screened the concentration of 65 elements (rare earth and platinum group elements, alkali metals and alkali earth metals, transition and post-transition metals and metalloids) and cyanide concentrations in wastewater samples collected from tailing impoundment; (iii) evaluated the toxicity of these water samples using five in vitro bioassays employing human cells isolated from healthy donors and a short-term (1 h) exposure model. The sampled waters were highly acidic (pH 2.1-4.9) and had high electrical conductivity (2.80-15.61 mS cm -1 ). No cyanides were detected in any sample. Water samples collected from the stream (AMD) inflowing to the tailing impoundment were characterized by the greatest concentrations of alkali metals, alkaline earth metals, transition and post-transition metals, metalloids, rare earth elements, and noble metal group. At other sites, the elemental concentrations were lower but remained high enough to pose a relevant risk. The greatest magnitude of in vitro toxic effects was induced by AMD. Observed alterations included redox imbalance in human neutrophils followed by lipid peroxidation and decreased cell survival, significant aggregation of red blood cells, and increased prothrombin time. The study highlights that Valea Şesei is a large sink for toxic elements, posing environmental and health risks, and requiring action to prevent further release of chemicals and to initiate restoration of the area.

Introduction: Imaging studies make it possible not only to visualize the general structure of the brain but also to take precise measurements of brain tissue volume and the size of individual lobes and their structure. The aim of this study was to determine the ratio of cerebrospinal fluid (CSF) volume contained in the intracranial ventricular system to the brain tissue volume and the ratio of CSF volume in the subarachnoid space and basal cisterns to the brain tissue volume., Material and Methods: The evaluation of volumetric measurements of computed tomographic (CT) images was undertaken on 23 male and female patients (average age 56.9 ± 6.1) diagnosed with normal pressure hydrocephalus (NPH) and 27 male and female patients (average age 70.6 ± 5.2) diagnosed with brain atrophy (BA). In the CT imaging studies, the total brain tissue volume and CSF volume collected in the intracranial fluid cavities were mapped to a colour scale. The VisNow software was used for volumetric evaluation. The groups were compared by means of the non-parametric Kolmogorov-Smirnov test (K-S) for independent samples. Paired data were compared by means of the nonparametric Wilcoxon test., Results: The volumes of brain (brain volume - BV) and cerebrospinal fluid (fluid volume - FV) differ greatly from each other in both groups BA and NPH. The SBR (subarachnoid space and basal cisterns-to-brain ratio) and VBR (ventricle-to-brain ratio) indicators differ significantly and very much within the NPH group as well as within the BA group. In the NPH group a clearly higher value of VBR can be observed in comparison with the BA group. There was a higher value of SBR in the BA than the NPH group., Conclusions: The simultaneous use of two indicators, VBR and SBR, on a study group of 50 patients enabled the total separation of NPH and BA groups. This differentiation can have real diagnostic value. Thus the volumetric assessment of the volume of CSF and brain tissue based on CT of the head can become an important part of the differential diagnosis of hydrocephalus and brain atrophy.

Introduction: A variety of diagnostic methods in normal pressure hydrocephalus and brain atrophy, it testifies to the difficulties in contrast to both teams. Develop a safe diagnostic tool having comparable statistical accuracy of the infusion test results would be of great clinical significance. The chances of implementing such a procedure in clinical practice, it may be a combination of these syndromes in the functional assessment (Posturography) the assessment of morphological CNS (volumetric)., The Aim: To evaluate and summary of the results of two non-invasive diagnostic methods morphological (posturography) and functional (volumetric) with results that were obtained from tests infusion., Material and Methods: The evaluation of volumetric and posturographic research was conducted in 39 patients including 27 patients with brain atrophy (BA) and in 12 patients with hydrocephalus (NPH). Volumetric measurements were made using proprietary software VisNow. Posturographic measurements performed using manual posturograph Pro-Med., Results: Both the volume of CSF obtained by volumetric assessment, as well as the values of the analyzed parameters posturographic, highly correlate with the results of resistance resorption (R). The BA radius values sway with eyes open and closed R_OZ R_OO were consistent with test results infusion of 100% in the NPH radius values showed 75% compliance with the test results infusion. Volumetric parameters: the volume of CSF contained in the subarachnoid space and basal cisterns (SV) and the volume of CSF system intracranial ventricular (VV) were found in both patients NPH and BA 100% compatible resorption resistance (R)., Conclusions: Simultaneous use of two non-standard methods of non-invasive (posturographic and volumetric) in the diagnostic process is a proposal to recognize normal pressure hydrocephalus and brain atrophy non-invasive methods, while maintaining very high statistical significance.

The modified Blalock-Taussig shunt is a palliative operation for some congenital heart diseases. An artificial conduit with antithrombotic surface placed between the subclavian (or innominate) and the pulmonary artery supplies blood to the lungs in defects with decreased pulmonary flow. Clotting of the graft is the main cause of its failure. Stenosis of the arteries is also observed. The objective of the present study was to investigate the flow pattern in the graft to investigate the possibility that clotting is initiated by the stimulation of platelets by high shear stress, and the possible effect of the pathological wall shear stress on the stenosis formation. The model included the left subclavian artery (LSA), the left pulmonary artery (LPA), and the graft. The three-dimensional relative position and size of the arteries was obtained from a CT scan of real anatomy. Four different types of the graft with two different diameters (3 and 4 mm) and two different shapes (straight and curved) of the pipe, and one variable diameter pipe were inserted in the model. A pulsatile flow of 0.81 L/min on average was assumed at the inlet to LSA, and 80% of the flow was directed through the graft. Computer simulations demonstrated a complex flow pattern with eddies and low velocity regions in the arteries at the anastomoses with the graft in all five models. An eddy was also found inside the straight 4 mm graft. A high pathological shear rate was present within the graft, with higher values in the 3 mm grafts. The fractional volume with a high (>2500 L/s) shear rate was between 2.5% and 4.5%, and that with a very high (>7500 L/s) shear rate between 0 and 1.5% of the model volume, and depended on the graft geometry and the phase of the cardiac cycle. Pathologically high (>3.5 Pa) and pathologically low (<1.0 Pa) wall shear stress, which may induce neointimal growth, was found in LSA and LPA. We conclude that the activation of platelets by high shear rate is possible within the graft, followed by their subsequent aggregation in the eddies with a low flow rate. Flow-induced changes of the vessel wall thickness (stenosis) can also appear, especially in the pulmonary artery.

Analysis of scalp-recorded potentials (EEG or evoked potential examination) is of great importance for studying bioelectrical processes in the human brain both in normal and pathological cases. Investigating potential distributions in the relation to individual topography of the cortex is helpful in treatment and surgery planning. We developed a method providing visual presentation of electrical potentials measured in EEG examination superimposed on a patient's cortex surface computed from MRI data. Analysis of such images contributes into diagnostics of common neurological disorders (for example: epilepsy, Parkinson's disease, any mechanical damage). Integration of EEG and MRI data sets requires their alignment. This paper focuses on applying a new registration technique for the alignment of these two data sets. The method does not require any external fiducial markers to be fixed on a patient's head, what makes it convenient for numerous examinations performed in clinic. Alignment bases on geometrical features derived from intrinsic data of an image or an object. To show the example of usage of the technique for assisting in neurological diagnostics we present results of SEP (sensory evoked potential) examinations performed for one pathological case and a control group.