54 research outputs found
Interplay between reactive oxygen species and autophagy in the course of age-related macular degeneration
Pathological biomolecules such as lipofuscin, methylglyoxal-modified proteins (the major precursors of advanced glycationend products), misfolding protein deposits and dysfunctional mitochondria are source of oxidative stress and act as strong autophagic stimulators in age-related macular degeneration. Disturbed autophagy accelerates progression of the disease, since it leads to retinal cells’ death and activates inflammation by the interplay with the NLRP3 inflammasome complex. Vascular dysfunction and hypoxia, as well as circulating autoantibodies against autophagy regulators (anti-S100A9, anti-ANXA5, and anti-HSPA8, A9 and B4) compromise an autophagy-mediated mechanism as well. Metformin, the autophagic stimulator, may act as a senostatic drug to inhibit the senescent phenotype in the age-related macular degeneration. PGC-1α , Sirt1 and AMPK represent new therapeutic targets for interventions in this disease
Mid-Holocene horizons of strongly decomposed peat and problems of dating paleohydrological changes in mires in the Racibórz basin, Southern Poland
During litho-stratigraphic studies of deposits in small mires in the upper basin of the Oder River, mid-Holocene hiatuses identified by the presence of horizons of strongly decomposed peat (HSDP), were identified at four sites. Radiocarbon dating results indicate long (103 years) breaks in peat accumulation and the dates obtained from the underlying layers of deposit are inconsistent with the pollen record. In order to explain these discrepancies, an attempt was made to recreate the condi-tions of HSDP formation under the influence of endo- and exogenous factors determining peatland productivity. In the light of macrofossil analysis, the development of HSDP during the Atlantic and Subboreal periods, when the humidity of habitats decreased, occurred at an advanced stage of devel-opment of swamps with Alnetea glutinosae forest communities. The gradual rise in water levels in the mires that started in the Subboreal period and intensified during the Subatlantic period was recorded as a slow shift in vegetation towards non-forest, sedge-moss communities belonging to the Mag-nocaricion alliance or the Scheuchzerio-Caricetea nigrae class. One consequence of the mechanism of HSDP formation is the existence of limitations on the dating of the duration of the dry phase owing to the presence of organic matter of different ages in the degraded peat layer. The determination of the age of wet phases offers better prospects. In the light of radiocarbon dating, which is essentially in line with the pollen analysis results, the transition towards positive peatland productivity occurred be-tween ca. 9th century BC and 7th century CE
Walory geologiczno-geoturystyczne Myszkowa
The natural and geological values of Myszków have been presented. A geological map of Myszków and a model of altitudes has been elaborated. Attention has been drawn to the most interesting elements of the surface geological structure. Unique for the region geoturistic values and potential geosites. Against this background, the excavations after the exploitation of the rock materials preserved in the site have been presented. Also, the most interesting amongst them have been characterized
Geoturystyczne walory gminy Janów
The natural and geological values of Janów municipality have been presented. A geological map of Janów and a model of altitudes has been elaborated. Attention has been drawn to the most interesting elements of the surface geological structure. Unique for the region geotouristic values and potential geosites. Against this background, the excavations after the exploitation of the rock materials preserved in the site have been presented. Also, the most interesting among them have been characterized
Walory geologiczno-geoturystyczne na obszarze gminy Żarki
The natural and geological values of Żarki community have been presented. A geological map and a model of altitudes has been elaborated. Atten-tion has been drawn to the most interesting elements of the surface geological structure. Unique for the region geotou-ristic values and potential geosites. Against this background, the excavations after the exploitation of the rock materials preserved in the site have been presented. Also, the most interesting among them have been characterized
The excavation of rock raw materials – anthropogenic islands cultural landscape
We analyzed the characteristics of islands and inslarity in the evaluation of landscape. Clarifies the meaning of the above mentioned terms. Identified the role of islands in studies of landscape, especially in the classification and evluation. Disscused the meaning of excavations of rock raw materials as an example of a dynamic island in the landscape. The need of introduction for studies of landscape for islands and insularity were justified especially in case of areas covered by mining work as landscape category classification
Walory geologiczne gminy Woźniki
Presented natural and geo-logical municipalities Woźniki. Summarizes the geological map of the municipality and the model of altitude. Drew attention to the most interesting elements of superficial geology, as well as advantages and potential geotouristic geosites
Walory geologiczno-geoturystyczne gminy Koziegłowy
The natural and geological values of the Koziegłowy municipality have been presented. A geological map of the municipality and a mo-del of altitudes has been elaborated. Attention has been drawn to the most interesting elements of the surface geological structure. Unique for the region geoturistic values and potential geosites. Against this background, the excavations after the exploitation of the rock materials preserved in the site have been presented. Also, the most interesting amongst them have been characterized
Stratygrafia pyłkowa i historia roślinności interglacjału mazowieckiego i starszej części zlodowacenia liwca w zachodniej i środkowej części Wyżyn Polskich
The goal of this work is to analyse vegetation
changes during the Mazovian Interglacial and the older
part of Liviecian Glaciation in the western and central
parts of Polish Uplands (Figs 1—6). The investigation
has been based on results of pollen analysis (Tab.
8—12, Figs 7—18) and examination of macroscopic remains
of plants (Tab. 15—21, Figs 28—36) from six
sites (Konieczki, Raków, Malice, Wielki Bór, Katowice
and Białe Ługi) as well as additional results from archival
sites prepared by other authors. Pollen successions
in new sites represent all basic features, which were
characteristic for the succession of the Mazovian Interglacial,
the typical order of pollen culmination of particular
trees, occurrence of yew (Taxus), interglacial increase
in pine (Pinus sylvestris t.) values, coexistence of
high values of hornbeam (Carpinus) and fir (Abies) pollen
in the younger part of the interglacial period and occurrence
of marker taxa, such as Pterocarya, Celtis and
Azolla filiculoides.
There have not been found any sediments representing
the end of the San Glaciation 2, preceding the
Mazovian Interglacial. The forest landscape in the oldest
part of the interglacial was homogenous, without any
significant regional variation. A high proportion of
Betula alba t. pollen, in some samples reaching even
93% (Fig. 19), proves there were almost only birch forests
then. Changes in the forest landscape were caused
by expansion of pine (Pinus sylvestris t.) and later of
spruce (Picea abies) and alder (Alnus). Further expansion
of yew (Taxus) caused great changes in the upland
forest landscapes, which were dominated by yew communities
(maximum pollen proportion 62% in
Konieczki, 53% in Malice, 52% in Raków and 46% in
Wielki Bór, Figs 20, 21, 37). Later, the upland area became
dominated by pine and birch communities, which
was the result of cool climatic oscillation. Increase of
importance of hornbeam and fir initiated further
changes in the forest communities. At the end of the
interglacial, importance of pine increased again and
thermophilous trees retreated from the upland areas
(Figs 24, 25). Changes of vegetation, which occurred due to climate
worsening, have been recorded in sediments from
all the sites. The succession of pollen was the most
complete in the older part of the Liviecian Glaciation in
the Wielki Bór profile (WB1 and WB2), where three
cold and two warm oscillations of the climate, as stadial
and interstadial, have been registered and in Raków (R1)
site, two stadial and two interstadial ones have been
found. The other sites (Konieczki, Malice 3, Katowice 1
and Białe Ługi 1, 2, 3 and 4 profiles) represent the fragment
of the I stadial only (Figs 26, 27).
Organic sediments in the older part of the Mazovian
Interglacial are most frequently represented by alternative
strata of silt and gyttja (Tab. 1—5) and they do not
contain macroscopic plant remains. The remains appeared
in larger amount starting from the III period
sediments (Wielki Bór 1, Konieczki and Katowice 1) or
the IV pollen period (Malice 3). Contents of the macroscopic
plant remains, variety of green algae of the
Pediastrum genus, and spore-pollen data emphasise significant
changes of trophism in several lakes. Occurrence
of Isoëtes lacustris spores (micro- and
macrospores) in sediments in Białe Ługi (Fig. 35)
proves oligotrophic conditions, which existed in the lake
in the oldest and the youngest part of the Mazovian
Interglacial and the oldest part of the Liviecian Glaciation.
Occurrence of Isoëtes rugosa (micro- and
macrospores) in sediments in Wielki Bór (Fig. 31) can
be also correlated with the glaciation. Appearance of
Aracites interglacialis seeds, the species characteristic
for the interglacial, which has been determined in the
sediments in Białe Ługi, seems to be quite significant.
Similar course of pollen curves of the main taxa in
the profiles of the upland areas have enabled to correlate
most of the local pollen zones (L PAZ) with the regional
pollen zones (R PAZ) after KRUPIŃSKI (1995 a,
2000) (Tab. 22). Pollen successions from the uplands
have been compared with the successions from the
Podlasie region, as it is the only area in Poland with
a large number of sites of modern palynological studies
and a dense net of profile sampling. Increase in the val-ues of Betula and Pinus pollen in the younger part of
Alnus-Pices-Fraxinus zone (II pollen period, Fig. 20), is
a local feature characteristic for the pollen successions
in the sites in the Woźniki-Wieluń Upland (Konieczki,
Raków, Malice and Wielki Bór). It was probably caused
by drying of some of the habitats due to hydrological
changes.
Very high proportion of Carpinus pollen (39% and
49%), observed in Białe Ługi (BŁ1 and BŁ4) and
Zakrucze profiles (Fig. 23), not recorded in any other
sites of the Mazovian Interglacial, is an unexpected feature.
Expansion of the tree probably occurred in the
same time as the increase of pine importance in the
Woźniki-Wieluń Upland (Pinus-Picea-Carpinus or
Pinus-Carpinus zone, Fig. 22), which occurred in the
beginning of the interglacial climatic oscillation, resulting
from stronger influence of the continental climate.
Climatic and vegetation changes during the interglacial
climatic oscillation were probably stronger than it
has been assumed so far. The period of the most substantial
changes can be correlated with the Betula-Pinus
zone, which has been determined so far only in
Ossówka (KRUPIŃSKI, 1995 a), Woskrzenice (BIŃKA,
NITYCHORUK, 1995) and Konieczki (NITA, 1996, 1999).
Increase in the values of Betula and Pinus pollen and
concurrent, quite drastic decrease in the pollen proportion
of thermophilous trees of Betula-Pinus zone in
Raków and Białe Ługi profiles (Fig. 36), proves that
similar changes in the profiles from Konieczki and
Podlasie region were not incidental and did not have
a local character. Birch and pine forests expanded in
most of the area of Poland and thermophilous trees almost
completely retreated in that time. Only spruce
(Picea abies) and alder (Alnus) among the trees, which
had been previously dominating, remained in the forest
landscape.
Climatic optimum of the Mazovian Interglacial was
a relatively long time period. Warm and humid climate
already lasted during the expansion of yew (Taxus-Alnus
zone) and later during the development of communities
with hornbeam and fir (III pollen period according to
JANCZYK-KOPIKOWA, 1991). Quite possibly, the contemporary
average temperatures of July were slightly higher
than during the yew zone, however the period was not
stable as far as the climate was concerned. It is possible
to agree with KRUPIŃSKI (1995 a, 2000), that the climatic
optimum covered a relatively long time period from the
expansion of yew till the development of communities
with hornbeam and fir.
Modern climates in the western part of Polish Uplands
and Podlasie region vary much more significantly
than in the Mazovian Interglacial. Influence of the oceanic
climate reached further to the east than today. Differences
in the pollen successions in both of the areas
have been caused mainly by local factors such as: soils,
hydrological conditions or microclimates. Low and very
low pollen proportion of Carpinus and very high values
of Abies, found in the younger part of the III pollen periods
in the upland profiles (Figs 22, 23) might prove
slightly longer influence of the oceanic climate than in
the Podlasie region. However, even in that case influence
of local factors cannot be omitted. Fir (Abies alba),
as a „mountain” species, could have found more favouring
expansion conditions in the upland
Krzywopłoty – Late Glacial and Holocene Mire in the Bydlin Area (Częstochowa Upland)
Macroscopic and laboratory tests of over 4-metre-thick organic
deposits of Krzywopłoty profile (gyttjas and peat) allowed the authors
to identify the development of the peatland as having four phases, each
transition being associated with fluctuations in water level. Sediments from
a depth of 3.75–0.65 m were also included in palynological testing. Seven
local pollen assemblage zones show a continuous transformation in the plant
landscape and surroundings of the site between the end of the Vistulian
and the Holocene. Pollen data indicates a change of vegetation, from open
communities of herbaceous plants and loose pine-birch communities in the
Younger Dryas, then dense pine forests in the Preboreal chronozone, and
finally multispecies forests in the Atlantic and Subboreal chronozones
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