77 research outputs found
Mild hydration of didecyldimethylammonium chloride modified DNA by 1H-nuclear magnetic resonance and by sorption isotherm
The gaseous phase hydration of deoxyribonucleic acid and didecyldimethylammonium chloride (C19H42ClN) complexes (DNA-DDCA) was observed using hydration kinetics, sorption isotherm, and high power nuclear magnetic resonance. Three bound water fractions were distinguished: (i) a very tightly bound water not removed by incubation over silica gel, (ii) a tightly bound water saturating with the hydration time t(1)(h) (0.596 +/- 0.04) h, and a loosely bound water fraction, (iii) with the hydration time t(2)(h) (20.9 +/- 1.3) h. Proton free induction decay was decomposed into the signal associated with the solid matrix of DNA-DDCA complex (T-2S approximate to 30 mu s) and two liquid signal components coming from tightly bound (T-2L1 approximate to 100 mu s) and from loosely bound water fraction (T-2L2 approximate to 1000 mu s)
Brain architecture in the terrestrial hermit crab Coenobita clypeatus (Anomura, Coenobitidae), a crustacean with a good aerial sense of smell
<p>Abstract</p> <p>Background</p> <p>During the evolutionary radiation of Crustacea, several lineages in this taxon convergently succeeded in meeting the physiological challenges connected to establishing a fully terrestrial life style. These physiological adaptations include the need for sensory organs of terrestrial species to function in air rather than in water. Previous behavioral and neuroethological studies have provided solid evidence that the land hermit crabs (Coenobitidae, Anomura) are a group of crustaceans that have evolved a good sense of aerial olfaction during the conquest of land. We wanted to study the central olfactory processing areas in the brains of these organisms and to that end analyzed the brain of <it>Coenobita clypeatus </it>(Herbst, 1791; Anomura, Coenobitidae), a fully terrestrial tropical hermit crab, by immunohistochemistry against synaptic proteins, serotonin, FMRFamide-related peptides, and glutamine synthetase.</p> <p>Results</p> <p>The primary olfactory centers in this species dominate the brain and are composed of many elongate olfactory glomeruli. The secondary olfactory centers that receive an input from olfactory projection neurons are almost equally large as the olfactory lobes and are organized into parallel neuropil lamellae. The architecture of the optic neuropils and those areas associated with antenna two suggest that <it>C. clypeatus </it>has visual and mechanosensory skills that are comparable to those of marine Crustacea.</p> <p>Conclusion</p> <p>In parallel to previous behavioral findings of a good sense of aerial olfaction in C. clypeatus, our results indicate that in fact their central olfactory pathway is most prominent, indicating that olfaction is a major sensory modality that these brains process. Interestingly, the secondary olfactory neuropils of insects, the mushroom bodies, also display a layered structure (vertical and medial lobes), superficially similar to the lamellae in the secondary olfactory centers of <it>C. clypeatus</it>. More detailed analyses with additional markers will be necessary to explore the question if these similarities have evolved convergently with the establishment of superb aerial olfactory abilities or if this design goes back to a shared principle in the common ancestor of Crustacea and Hexapoda.</p
Copper, zinc, manganese and iron concentrations in soils of 27 and 30-year-old apple tree orchards
Ocena wpływu wieloletniego użytkowania sadowniczego na całkowitą zawartość Cu, Zn, Mn i Fe w glebie oraz zawartość tych metali ekstrahowanych DTPA była celem niniejszych badań. Do badań wytypowano 3 sady jabłoniowe założone na glebach brunatnych wytworzonych z gliny zwałowej w regionie Doliny Brdy. Poziomy próchniczne badanych gleb charakteryzowały się znacznie wyższą całkowitą zawartością Cu i Zn w porównaniu do koncentracji tych metali w skale macierzystej. Udział miedzi ekstrahowanej roztworem DTPA w stosunku do jej całkowitej zawartości był wysoki i dochodził w poziomie próchnicznym do 24,6%. Stwierdzono istotną dodatnią korelację między całkowitą zawartością Cu i Zn oraz zawartością tych metali ekstrahowanych DTPA a zawartością węgla organicznego. Kwaśny odczyn w poziomach próchnicznych badanych gleb miał istotny wpływ na wzrost zawartości Cu, Mn i Fe ekstrahowanych DTPA, co potwierdziły dodatnie, statystycznie istotne współczynniki korelacji między tymi parametrami. Stwierdzone zawartości Cu, Zn, Mn oraz Fe nie przekroczyły dopuszczalnych norm przyjętych dla gleb nie zanieczyszczonych tymi metalami.The aim of this study was to estimate the long-term effect of orcharding utilization on the total content of Cu, Zn, Mn, Fe and their available forms in soils. For the investigation three apples tree orchards planted on the Cambisols from the Brda Valley Region were selected. The content of Cu and Zn in the humus horizon was much higher than in parent material due to the anthropogenic pollution. In the analyzed soils it was observed that, total Cu and Zn content and DTPA-extractable Cu, Zn, Mn, Fe was statistically positively correlated with the content of organic carbon. The content of DTPA-extractable Cu to the total content of Cu was high and reached up to 24,6% at the humus horizon. It was stated, that available forms of copper, manganese and iron was statistically positively correlated with the acid reaction. The total content of Cu, Zn, Mn and Fe did not exceed acceptable concentrations for uncontaminated soils
Mercury in the soils of the hunting plots and the surrounding forests
Some trace elements, because of their high capacity for bioaccumulation, can pose a threat to the adequate development and growth of plants, animals and humans, which concerns mostly mercury (Hg) and its compounds that characterize by strong toxic properties. The aim of the research was to compare the Hg content in the Arenosols of arable fields (food plots), referred to as hunting plots, as well as in the soils of neighbouring forests. Research was performed in the Szubin Forest District (northern Poland). To assess the effect of mercury on the environment, we used dandelion (Taraxacum officinale) as a bioindicator. The samples were collected from the soil profiles from 8 hunting plots and 8 woodland areas in close vicinity of these plots. Mercury was assayed with the atomic absorption spectrometry applying the AMA 254 analyser. The mercury contamination factor (CF) and the potential ecological risk index (Er) values were determined with the local Hg value of the geochemical background (5.7 µg/kg). Assuming such very low Hg concentration as the reference value for the parent material of the soils, the mean CF value points to a considerable anthropogenic mercury accumulation in the surface horizons. The soils of hunting plots as well as forest soils are not contaminated with mercury. The total Hg content falls within the natural content level and reaches in the mineral horizons – from 3.5 to 20.7 µg/kg, while in the litter layer – from 60.3 to 166.7 µg/kg. The mercury bioconcentration factor (BCF) and translocation factor (TF) values point to a clear accumulation in the aboveground parts of dandelion. We found a significantly positive correlation between the content of mercury and organic carbon as well as the clay fraction. The mercury content in the soils under study varies and it depends on the soil origin and the effect of anthropogenic factors. In the forest soils of the Pomorze and Kujawy Province the mercury content of the geochemical background is relatively low. The areas of the Szubin Forest District do not undergo an excessive anthropopressure and sources of Hg depositions in soil surfaces can be the deposition of mercury from air
Selected problems of the Polish Navy warships artillery systems development
W artykule przedstawiono prawidłowości rozwoju okrętowego uzbrojenia artyleryjskiego i problemy z tym związane. Uwzględniono w nim różne podejścia interpretacji rozwoju okrętowego uzbrojenia artyleryjskiego i doświadczenia MW RP oraz ocenę obecnego stanu rozwoju okrętowego uzbrojenia artyleryjskiego.Some main tendencies in the development of the naval artillery systems for the Polish Navy and the evaluation of the existing situation in this matter are presented in the paper
Lokalna zawartość tła geochemicznego metali ciężkich w różnych typach gleb wytworzonych z gliny zwałowej Równiny Inowrocławskiej
In the present study, local background concentrations of heavy metals were determined
in soils which have been minimally influenced by human activities. The ground moraine
landscape of the Inowrocławska Plain is dominated by Phaeozems, which occur in numerous
associations with Luvisols and Cambisols. Four profiles of Phaeozems, three profiles
of Luvisols and two profiles of Cambisols had been researched earlier, especially their morphology,
selected physicochemical properties, texture and mineralogical composition. Selected
properties were also measured to determine their influence on the content and distribution
of trace elements in soil profiles. For determination of the concentration of metals
in the soil profiles, the following indices were used: distribution factor (DI), enrichment
factor (EF) and transfer factor (TF). The total content of metals in the genetic horizons
and the local geochemical background level of metals in soils were determined. With the
knowledge of the natural content of elements in the parent material, assumed to be the
geochemical background, a degree of contamination of surface soil horizons can be evaluated.
The content of Zn, Cu, Ni, Pb, Cr, Mn (mg kg–1) and Fe and Ti (g kg–1), which was
defined as the content of the local background, was: 40.6; 12.6; 14.3; 12.9; 5.5; 309.9 and
16.5; 1.4, respectively. The distribution of Ni, Cr, Cu, Mn and Fe in the soil profiles can be
explained as the effect of pedogenic factors, although in the case of, a tendency towards
accumulation of Zn and Pb in the humus horizons as a result of anthropogenic input was
observed. The distribution of pedogenic Ni, Cu, Cr and Mn was influenced by specific adsorption
of metals on Fe oxides. The results indicate that the metals were bound more
strongly to iron oxides than to organic matter. Based on the results of geochemical studies
on selected arable soils from the Iowrocławska Plain, an integrated method was applied to
assess the local background using an iterative 2s-technique (mean + 2 standard deviation).
The relationships between trace elements and the conservative element such as Fe were used to predict the expected values of trace elements in topsoil. The results substantiate
the importance of determining local background concentrations
Zawartość przyswajalnych form magnezu, fosforu i potasu w glebie pod wpływem zmianowania i nawożenia
Soil richness in available magnesium, phosphorus and potassium forms is one of the
key factors of fertility, which ensures the potential of soil for satisfying nutritional requirements
of plants. The aim of the present research has been to determine the effect of
crop rotation and varied mineral and organic fertilisation on the content of available Mg,
K and P forms. Soil was sampled from a long-term experiment, carried out on Luvisol
formed from sandy loam (soil valuation class IVa, very good rye complex). The experiment
was performed in a 3-factor design, which included two types of crop rotation as well as
FYM and nitrogen fertilisation. Basic physicochemical properties of soil were determined.
The content of available forms of magnesium was defined with Schachtschabel method
and the content of potassium and phosphorus – with Egner-Riehm method (DL). The reaction
in the arable-humus horizon of the soils ranged from 4.7 to 6.2. It was found that
the Corg to Nt ratio in the arable-humus horizon of soils of all the experiment variants
was typical of biologically active soils. The content of available magnesium ranged from
27.8 to 58.3 mg kg–1 of soil, while its water-soluble forms varied from 3.5 to 6.8 mg kg–1
of soil. The highest content of magnesium, potassium and phosphorus forms available to
plants was observed after the application of FYM in the doses of 60 and 80 t ha–1 combined
with mineral nitrogen fertilisation, in both crop rotation regimes. The content of magnesium
and phosphorus forms available to plants was significantly positively correlated
with the content of organic carbon. Soil sampled from those plots demonstrated higher
classes of the content of that element. The research data proved that the analysed soils
showed moderate and high richness in nutrients available to plants. High doses of organic and mineral fertilisation, however, did not increase significantly the electrolytic conductivity
of the soil solution.Zasobność gleby w dostępne dla roślin formy magnezu, fosforu i potasu jest jednym
z ważniejszych elementów jej żyzności, warunkujących możliwości gleby do zaspokojenia potrzeb
pokarmowych roślin. Celem badań było określenie wpływu zmianowania i zróżnicowanego
nawożenia mineralno-organicznego na zawartość przyswajalnych form Mg, K i P.
Próbki do badań pobrano z wieloletniego doświadczenia statycznego, prowadzonego na glebie
płowej wytworzonej z gliny lekkiej (IVa klasa bonitacyjna, kompleks żytni bardzo dobry).
Doświadczenie prowadzono w układzie 3-czynnikowym, obejmującym: 2 typy zmianowania;
nawożenie obornikiem i nawożenie azotem. Oznaczono podstawowe właściwości
fizykochemiczne gleb. Zawartość przyswajalnych form magnezu określono metodą Schachtschabela,
a potasu i fosforu metodą Egnera-Riehma (DL). Odczyn w poziomie orno-próchnicznym
badanych gleb wahał się od 4,7 do 6,2. Stwierdzono, że stosunek Corg do Nt w poziomie
orno-próchnicznym gleb we wszystkich wariantach doświadczenia był typowy dla gleb
aktywnych biologicznie. Zawartość magnezu przyswajalnego wynosiła od 27,8 do 58,3 mg kg–1
gleby, natomiast jego form wodno-rozpuszczalnych od 3,5 do 6,8 mg kg–1 gleby. Najwyższą zawartość przyswajalnych dla roślin form magnezu, potasu i fosforu zaobserwowano po zastosowaniu
obornika w dawkach 60 i 80 t ha–1 łącznie z nawożeniem azotem
mineralnym, w obu rodzajach zmianowania. Zawartość form magnezu i fosforu przyswajalnych
dla roślin była istotnie dodatnio skorelowana z zawartości¹ węgla organicznego. Glebę z tych poletek można było zaliczyć do wyższych klas zawartości tego pierwiastka. Na
podstawie wyników badań stwierdzono, że analizowane gleby charakteryzowały się średnią
i wysoką zasobnością w składniki pokarmowe dla roślin. Wysokie dawki nawożenia organicznego
i mineralnego nie wpłynęły w istotny sposób na wzrost przewodnictwa elektrolitycznego
roztworu glebowego
Kompleks sorpcyjny wybranych gleb pojezierza drawskiego
Magnesium, calcium, potassium and sodium occur in soil in various forms but for plant
nutrition their exchangeable forms are the most important. Cations bonded in soil colloids
constitute a specific reservoir of nutrients.
The aim of this research was to determine sorption properties and to evaluate the
distribution of exchangeable cations in the profiles of soils of the Drawskie Lakeland. Samples
were taken from 6 soil profiles formed from glacial till of the Baltic glaciation in the
vicinity of Złocieniec and Czaplinek. In general, the sampled soils had the grain-size composition
of loams. The reaction of most soil samples was acid. Exchangeable cations were
extracted with the BaCl2 solution according to PN-ISO 11260. The cation exchange capacity
(CEC) ranged from 52.6 to 216.6 mmol(+) kg–1 of soil. The soils, despite acid reaction,
were sorption-saturated. Alkaline cations were dominated by calcium, whose highest share
in the sorption capacity was identified in the horizons of the parent material of all the
examined soils. The lowest amounts of exchangeable calcium and magnesium were found
in horizons Ap and Eet. The horizons rich in clay fraction contained higher contents of
Ca2+ and Mg2+, which was confirmed by significantly positive correlation. The acid reaction
did not affect significantly either the content of exchangeable cations or their distribution
in the soil profiles. The highest content of K+ in arable-humus horizons of some of the
soils can be related to potassium fertilisation and the weathering of minerals containing
that metal. The highest content of magnesium and calcium cations in horizons Bg and the
parent material of Gleysols point to the possibility of some overlapping of the top-down
gleyic process features with lessivage features.Magnez, wapń, potas i sód występują w glebie w różnych formach, z których najważniejsze w aspekcie odżywiania roślin są ich formy wymienne. Zasorbowane w koloidach
glebowych kationy stanowią swoisty rezerwuar składników pokarmowych.
Celem badań było określenie właściwości sorpcyjnych oraz ocena rozmieszczenia kationów
wymiennych w profilach gleb Pojezierza Drawskiego. Próbki do badań pobrano
z 6 profili gleb wytworzonych z gliny zwałowej zlodowacenia bałtyckiego z okolic Złocieńca
i Czaplinka. Badane gleby charakteryzowały się na ogół uziarnieniem glin. Większość próbek
glebowych miała odczyn kwaśny. Kationy wymienne ekstrahowano roztworem BaCl2
zgodnie z normą PN-ISO 11260. Pojemność wymienna (CEC) wynosiła od 52,6 do 216,6
mmol(+) kg–1 gleby. Badane gleby pomimo kwaśnego odczynu były sorpcyjnie nasycone.
Wśród kationów zasadowych dominował wapń, którego najwyższy udział w pojemności
sorpcyjnej stwierdzono w poziomach ska³y macierzystej wszystkich badanych gleb. Najmniej
wymiennego wapnia i magnezu stwierdzono w poziomach Ap i Eet. Poziomy zasobne w ił
koloidalny zawierały więcej Ca2+ i Mg2+, co potwierdziła istotnie dodatnia korelacja. Kwaśny
odczyn nie wpłynął w istotny sposób na zawartość kationów wymiennych oraz ich rozmieszczenie
w profilach gleb. Najwyższą zawartość K+ w poziomach orno-próchnicznych kilku
gleb można wiązać z nawożeniem potasem oraz wietrzeniem minerałów zawierających
ten metal. Najwyższe zawartości kationów magnezu i wapnia w poziomach Bg oraz stropie
skały macierzystej gleb opadowo-glejowych wskazują na możliwość nakładania się cech procesu
odgórnego oglejenia na cechy procesu lessivage
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