The primary production of phytoplankton in the restored Maltañski Reservoir in Poland

Patterns in composition, abundance and diversity of the annelid fauna (Polychaeta and Oligochaeta) in 22 sandy beaches in Iceland were explored. The effect of exposure on annelid distribution was studied. A total of 5651 annelids were recorded from 160 core samples. Oligochaetes (chiefly Tubificidae) dominated the annelid assemblage whereas polychaetes represented a minor fraction. Polychaetes were relatively more abundant in exposed than in sheltered beaches, contrary to oligochaetes. Meiofaunal polychaete species were also more abundant in exposed than in sheltered beaches. Southwest beaches seemed more diverse in annelid species than northern ones. Annelid diversity did not differ between sheltered and exposed sites, but higher diversity was attained in fine sands at sheltered areas. Cluster analysis revealed large differences between beaches in the annelid community composition. The general patterns found suggest that beach exposure is a major factor conditioning macro- and meiofaunal polychaete and oligochaete distribution along the Icelandic coast.     

The dynamics of a non-forested stand in the Krušné Mts.: the effect of a short-lived medieval village on the local environment

Vegetation History and Archaeobotany - Medieval vegetation–human–climate interactions were studied from a sediment profile situated in the centre of a short-lived medieval village...     

Living on the edge – The predicted impact of renewed hunting on moose in national parks in Poland

Protected areas are the foundation of biodiversity conservation. However, due to their limited size, unfavourable shape, and isolation they often rarely provide sufficient protection. This problem particularly concerns large mammals, which play the role of key-species and usually have high spatial demands. Since 2001 the moose has been under a hunting ban in Poland after the species experienced a sharp decline due to overharvesting. As there are plans to reopen moose hunting in eastern Poland (excluding national parks and nature reserves), we analysed the potential impact of renewed hunting in areas neighbouring Biebrza and Polesie National Parks (eastern Poland) on moose populations inhabiting these protected areas and investigated the suitability of the existing buffer zones to provide additional protection to moose outside the park boundaries. Analyses were based on the tracking data derived from 33 GPS collared moose (24 – Biebrza NP and 9 – Polesie NP). All of the tracked moose utilized areas both inside and outside national parks. In the Biebrza PN, moose spent 46.9% of their time in areas surrounding the national park, whilst in Polesie NP the proportion was 64.5%. The highest utilization of areas outside both study sites occurred in autumn and winter (October–March), a period that considerably overlaps with the planned hunting season. The southern part of Biebrza NP and its official buffer zone covered 96.2% of all moose fixes, while Polesie NP, its official buffer zone and neighbouring landscape park covered 60.3% of moose records. The buffer zones proposed in this paper, whose widths were calculated on the basis of moose tracking data, would protect from 90.5 (Polesie) to 91.2% (Biebrza) of moose fixes. Proper delineation and adequate management plans in buffer zones would prevent the negative impacts of moose hunting, which has the potential to significantly influence ecotourism in national parks and their vicinity.     

The effect of anaerobiosis on the induced synthesis of β-galactosidase in non-growingEscherichia coli

Depending on conditions of aeration maltose and glucose were found to exhibit different effects on the inducible synthesis of β-galactosidase in aerobically grown cells ofEscherichia coli starving for an exogenous source of nitrogen; both saccharides repressed the synthesis of the enzyme under aerobic conditions, while the above-mentioned saccharides were essential for the enzyme synthesis under anaerobic conditions. The presence of maltose in the medium resulted in the repression of the enzyme synthesis in anaerobically grown cells starving for an exogenous nitrogen source under anaerobic conditions. The synthesis of β-galactosidase-specific messenger RNA was completely blocked and the synthesis of the enzyme proper considerably inhibited in aerobically grown cells incubated anaerobically in a medium without nitrogen and carbon sources.     

Storm-dominated deposition of the Lower Jurassic crinoidal limestones in the Krížna unit, Western Tatra Mountains, Poland

The Lower-Middle Jurassic of the Krína unit in the Western Tatra Mts. (southern Poland) shows considerable facies variation. Crinoidal grainstones of variable thickness (up to 12 m) are one of characteristic facies. They occur above spiculites which were deposited below storm wave base on the slopes of elevated horsts. First single beds of crinoidal limestones occur within spiculites. They were deposited as event beds, generated probably by storms. The overlying thick complex of well-sorted grainstones composed almost entirely of crinoidal ossicles display widespread erosional bed amalgamation, hummocks and locally wave-formed ripples. The above characteristics are the effects of multiple reworking and winnowing of fine crinoidal material by oscillatory currents related to storms. This proves that the sedimentation of the crinoidal grainstones took place between the storm and the fair-weather wave bases. The vertical transition from spiculites with intercalations of crinoidal limestone beds towards the crinoidal grainstones is interpreted as the result of a shallowing upward trend. Since this trend is opposite to the global Early Toarcian transgression, this could be related to an uplift due to local block tectonic activity. The evidence for that is diversification of facies in the Krína Basin, as well as submarine slumps recorded in spiculites. The location of Krína Basin on relatively low northern latitude and on western edges of great Tethys Ocean during Early Jurassic enabled the formation of the crinoidal tempestites.     

Structural characteristics and aboveground biomass of old‐growth spruce–fir stands in the eastern Carpathian mountains,Ukraine

Abstract

Temperate old‐growth forests are known to have ecological characteristics distinct from younger forests, but these have been poorly described for the remaining old‐growth Picea abies–Abies alba forests in the eastern Carpathian mountains. In addition, recent studies suggest that old‐growth forests may be more significant carbon sinks than previously recognized. This has stimulated interest in quantifying aboveground carbon stocks in primary forest systems. We investigated the structural attributes and aboveground biomass in two remnant old‐growth spruce–fir stands and compared these against a primary (never logged) mature reference stand. Our sites were located in the Gorgany Nature Reserve in western Ukraine. Overstory data were collected using variable radius plots; coarse woody debris was sampled along line intercept transects. Differences among sites were assessed using non‐parametric statistical analyses. Goodness‐of‐fit tests were used to evaluate the form of diameter distributions. The results strongly supported the hypothesis that old‐growth temperate spruce–fir forests have greater structural complexity compared to mature forests, including higher densities of large trees, more complex horizontal structure, and elevated aboveground biomass. The late‐successional sites we sampled exhibited rotated sigmoid diameter distributions; these may reflect natural disturbance dynamics. Old‐growth Carpathian spruce–fir forests store on average approximately 155–165 Mg ha^?1 of carbon in aboveground tree parts alone. This is approximately 50% higher than mature stands. Given the scarcity of primary spruce–fir forests in the Carpathian region, remaining stands have high conservation value, both as habitat for late‐successional species and as carbon storage reservoirs.     

The effect of counterion,water concentration,and stirring on the stability of subtilisin BPN′ in organic solvents

The stability of subtilisin BPN′ in organic solvents or cosolvent/water mixtures was studied as a function of the type and concentration of counterion at the time of freeze-drying, water concentration, and stirring speed/method. It was found that the enzyme is stabilized by high concentrations of counterion, at least at very high cosolvent concentrations. The type of counterion also has a remarkable impact on the enzyme stability; at high concentrations of DMF (dimethylformamide), multivalent counterions with low solubility in organic solvents are far superior to monovalent, soluble ones. Sodium citrate is the best salt tested in terms of enzyme stability, increasing the half life of the enzyme better than a millionfold over Tris in 99% DMF. The stability of the enzyme was found to have a complex dependence on the amount of water in the DMF. Enzyme lyophilized from the sodium phosphate displays a stability minimum at about 90% DMF, while enzyme lyophilized from Tris becomes increasingly unstable from 30% to 99% DMF, without inflection. Vigorous stirring with a magnetic stir bar, which broke apart the enzyme particles, was found to be extremely deleterious to enzyme stability, while swirling the enzyme with a wrist-action stirrer, which did not grind the enzyme particles, had no effect. Explanations for this are discussed.     

The effect of chondroitin sulphate–protein on the formation of collagen fibrils in vitro

1. It was found that the precipitation of collagen fibrils at 37 degrees from mixtures of chondroitin sulphate-protein and tropocollagen at physiological ionic strength and pH takes place in two distinct phases. The first occurs immediately on mixing either at 4 degrees or at 37 degrees , and the second occurs only at 37 degrees and after a lag phase whose magnitude depends on the proportions of components. 2. When the second stage of precipitation was inhibited by mixing the reactants at 4 degrees , the initial precipitate was found to contain ;native-type' collagen fibrils and chondroitin sulphate-protein. 3. On the basis of kinetic experiments it was concluded that aggregates of chondroitin sulphate-protein and tropocollagen form instantaneously and that these act as sites for the second stage of precipitation of fibrils. 4. The gels that result after continued incubation at 37 degrees are fibrous in appearance if formed in the presence of the initial precipitate of chondroitin sulphate-protein and tropocollagen. 5. On the basis of these experiments in vitro the authors propose a sequence of events for collagen fibrogenesis in vivo.     

The effect of 17-N substituents on the activity of the opioid κ receptor in nalfurafine derivatives

We have previously reported the essential structure of the opioid κ receptor agonist nalfurafine hydrochloride (TRK-820) for binding to the κ receptor. In the course of this study, we focused on the effect of the substituent at 17-N in nalfurafine on the binding affinity for the κ receptor. The exchange of the 17-N substituent in nalfurafine from cyclopropylmethyl to fluoro-substituted alkyl groups, which are strong electron withdrawing substituents, almost completely diminished the binding affinities for the μ and δ opioid receptors, but the binding affinity for the κ receptor was still maintained. As a result, nalfurafine derivatives with 17-fluoro-substituted alkyl groups showed higher selectivities for the κ receptor than did nalfurafine itself. With regard to the κ agonistic activities, the conversion of the 17-N substituent in nalfurafine from cyclopropylmethyl to fluoro-substituted alkyl groups led to the gradual decrease of the agonistic activities in the order corresponding to their binding affinities for the κ receptor. In contrast, the derivative with the bulky 17-isobutyl group showed lower affinity and agonistic activity for the κ receptor than the derivatives with the smaller functional groups. This research suggested that both the electronic property and the steric characteristics of the 17-N substituent would have a great influence on the binding property for the κ receptor.     

The effect of cross-links on the mobility of proteins in dodecyl sulphate–polyacrylamide gels

The effect of reduction of intramolecular disulphide bridges on the mobility of proteins in 5% (w/v) polyacrylamide gels in the presence of sodium dodecyl sulphate was investigated. A series of polypeptide polymers, containing up to 68 intramolecular disulphide bridges, was prepared by cross-linking proteins of known structure with glutaraldehyde. These model polypeptides were denatured with heat, sodium dodecyl sulphate and urea, and their mobilities in sodium dodecyl sulphate-polyacrylamide gels compared before and after reduction with dithiothreitol. The mobilities of polypeptides containing no cystine were unaffected by reduction. However, reduction generally decreased the mobilities of polypeptides containing cystine; the extent of this decrease depended on the number of cystine residues originally present in the polypeptide polymer, and on the protein from which the latter was derived. In contrast with their higher oligomers, the monomer of lysozyme and the dimer of ribonuclease increased in mobility after reduction. The reduced polypeptide oligomers formed by reaction with glutaraldehyde were generally found to migrate at a rate significantly faster than was expected from their calculated molecular weights. It was concluded that the use of unreduced proteins and protein aggregates for molecular-weight measurements by the sodium dodecyl sulphate-polyacrylamide-gel method may give erroneous estimates of the molecular weight of any protein being investigated.     

The effect of illumination on the pigment composition of the ζ-carotenic mutant,PG1, of Scenedesmus obliquus

Dark grown Scenedesmus obliquus strain PG1 accumulated -carotene and phytoene as its major carotenoids. On illumination of dark-grown cultures in air/CO₂, cyclic carotenes and xanthophylls were formed, apparently at the expense of the accumulated phytoene and -carotene. This interconversion of carotenoids was accompanied by chlorophyll synthesis. In an atmosphere of nitrogen/CO₂ the light-induced changes occurred more slowly and in nitrogen alone the changes were incomplete. No massive production of cyclic carotenes from the accumulated -carotene was observed in cultures illuminated under anaerobic conditions.     

The impact of meteorological conditions on the concentration of alder pollen in Sosnowiec (Poland) in the years 1997–2017

The aim of the work was to compare the alder pollen seasons in the years 1997–2017 in Sosnowiec. The measurements of pollen concentration were taken with the volumetric method using Burkard’s apparatus. The impact of atmospheric conditions on the daily alder pollen grain concentration, the annual totals, and the duration of pollen seasons were studied. The dependency between each meteorological condition and different features of the alder pollen season was determined by using Pearson’s correlation coefficients, variance analysis with multiple comparison tests, and the linear regression model using backward elimination. It was proven that the temperatures directly preceding the pollination, i.e. the January and February temperatures as well as those from the period from 210 to 180 days preceding the beginning of the season, have the greatest impact on the beginning of the alder pollen season. The value of the daily alder pollen concentration in Sosnowiec showed a positive statistically significant correlation with the air temperature and sunshine duration and a negative correlation with the thickness of the snow cover and air relative humidity. The daily concentration also depended on the type of the weather front, direction of air mass inflow, and the type of the inflowing air mass. The season temperatures and the thermal conditions which were present in the summer of the preceding year impacted the annual totals (SPI) of the alder pollen grains.     

Occurrence and chemical diversity of the genus Bryoria in the Sučí Potok Valley, Veporské Vrchy Mountains (Central Slovakia)

Four species of the genus, Bryoria were found in the Sučí Potok Valley: B. capilaris (Ach.) Brodo & D. Hawksw., B. fuscescens (Gyeln.) Brodo & D. Hawksw., B. implexa (Hoffm.) Brodo & D. Hawksw., B. nadvornikiana (Gyeln.) Brodo & D. Hawksw. The most common species in the valley was B. implexa. Four chemotypes of this lichen were recognized.     

Inhibition of staphylococcal α-toxin. The effect of aromatic polysulphonic acids on the lethal effect of α-toxin in mice

1. Certain aromatic polysulphonic acids, previously tested for inhibition of the haemolytic activity of staphylococcal α-toxin, together with some additional related compounds, were tested as possible inhibitors of α-toxin in mice. 2. Compounds that inhibited the haemolytic activity of α-toxin at concentrations of 0·16mm or less [compounds (I), (II), (IV), (V), (VII) and (VIII)] were found to inhibit the lethal effect of α-toxin. 3. With the exception of compound (VIII), amounts of 1mg. were required to inhibit 4 LD₅₀ of toxin when the test compounds were premixed with α-toxin before injection; comparable inhibition with 0·3mg. of compound (VIII) was achieved without prolonged premixing. 4. Mixtures of α-toxin and compounds (I) and (II) containing an excess of test compound showed markedly diminished inhibitory activities. 5. The `half-molecule' analogues of group 1 [compounds (III) and (XVIII)] were non-inhibitory. 6. Compounds (I)–(V), when administered separately from α-toxin by the same route (intraperitoneal), were active only when injected almost simultaneously with toxin, whereas compounds (VII) and (VIII) were strikingly inhibitory when injected 15min. before or after the toxin. 7. Compound (VIII) failed to inhibit the lethal effect of α-toxin when injected by a different route (intravenous).     

The effect of amino acid substitution in the imperfect repeat sequences of α-synuclein on fibrillation

Human α-synuclein is the causative protein of several neurodegenerative diseases, such as Parkinson's disease (PD) and dementia with Lewy Bodies (DLB). The N-terminal half of α-synuclein contains seven imperfect repeat sequences. One of the PD/DLB-causing point mutations, E46K, has been reported in the imperfect repeat sequences of α-synuclein, and is prone to form amyloid fibrils. The presence of seven imperfect repeats in α-synuclein raises the question of whether or not mutations corresponding to E46K in the other imperfect KTKE(Q)GV repeats have similar effects on aggregation and fibrillation, as well as their propensities to form α-helices. To investigate the effect of E(Q)/K mutations in each imperfect repeat sequence, we substituted the amino acid corresponding to E46K in each of the seven repeated sequences with a Lys residue. The mutations in the imperfect KTKE(Q)GV repeat sequences of the N-terminal region were prone to decrease the lag time of fibril formation. In addition, AFM imaging suggested that the Q24K mutant formed twisted fibrils, while the other mutants formed spherical aggregates and short fibrils. These observations indicate that the effect of the mutations on the kinetics of fibril formation and morphology of fibrils varies according to their location.     

The effect of nucleosides on the induced synthesis of β-galactosidase in non-growing cells ofEscherichia coli

The induced synthesis of β-galactosidase in non-growing cells ofEscherichia coli starving for exogenous carbon and nitrogen sources was stimulated markedly by the addition of any of four nucleosides tested: adenosine, guanosine, cytidine, and uridine. Adenosine was used as a representative of this group of compounds in most experiments. The decrease of ability of the cells to synthesize β-galactosidase, resulting from a prolonged starvation for exogenous carbon and nitrogen, was removed by adenosine. This compound also considerably reduced the inhibitory effect of metabolic poisons on the induced synthesis of β-galactosidase. The blockade of induced β-galactosidase synthesis evoked in aerobically grown cells by anaerobic starvation for exogenous sources of carbon and nitrogen was also significantly reduced by adenosine. The weak transient catabolic repression of induced synthesis of β-galactosidase evoked by glucose in non-growing cells ofEscherichia coli deprived of exogenous carbon and nitrogen sources was prevented by adenosine. The total repression caused by higher glucose concentrations was not influenced by this compound. The results are discussed from the point of view of the role of the energy state ofEscherichia coli cells in the regulation of β-galactosidase synthesis.     

Assemblage structure and altitudinal distribution of lady beetles (Coleoptera,Coccinellidae) in the mountain spruce forests of Pol’ana Mountains,the West Carpathians

In two successive years we recorded a total of 3,636 individuals and 17 species of adult lady beetles (Coleoptera, Coccinellidae) in the spruce forests of Pol’ana Mts (the West Carpathians) at altitudes ranging from 600 m to 1,300 m a.s.l. Four lady beetle species were documented as predominating (dominance of abundance > 5%) over the study period. They were the following: Aphidecta obliterata (1,828 individuals and 50.3%), Coccinella septempunctata (634 individuals and 17.4%), Adalia conglomerata (594 individuals and 16.3%) and Anatis ocellata (279 individuals and 7.7%). The assemblages of lady beetles differed among the areas and also between the years. The season revealed neglegible effect on distribution of lady beetles, whereas the effect of altitude was more pronounced. A. conglomerata preferred the areas at lower altitude (600–725 m) to those at middle (900–925 m) and/or upper altitude (1,250–1,300 m). In contrast, A. obliterata and C. septempuctata were most abundant in the area at middle altitude. The altitudinal location of area partly explained the variability in abundance of lady beetles. The first ordination axis constructed by means of correspondence analysis (CA) represented an altitudinal gradient and accounted for 19.4% of the total variance of the species data. The great proportion of lady beetle species not typically associated with spruce and/or other coniferous trees than spruce (70.6%, n = 17) may be explained by an ecotonal effect.