The high-temperature requirement for liquid iron smelting via molten oxide electrolysis presents significant challenges.This study investigates the electrochemical reduction of Fe(Ⅲ)in a novel low-temperature electro...The high-temperature requirement for liquid iron smelting via molten oxide electrolysis presents significant challenges.This study investigates the electrochemical reduction of Fe(Ⅲ)in a novel low-temperature electrolyte,Na_(2)SiO_(3)-SiO_(2)-Fe_(2)O_(3),utilizing cyclic voltammetry and square wave voltammetry techniques.The results show that Fe(Ⅲ)reduction occurs in two steps:Fe(Ⅲ)+e^(−)→Fe(Ⅱ),Fe(Ⅱ)+2e^(−)→Fe,and that the redox process of Fe(Ⅲ)/Fe(Ⅱ)at the tungsten electrode is an irreversible reaction controlled by diffusion.The diffusion coefficients of Fe(Ⅲ)in the molten Na_(2)SiO_(3)-SiO_(2)-Fe_(2)O_(3)in the temperature range of 1248–1278 K are between 1.86×10^(−6)cm^(2)/s and 1.58×10^(−4)cm^(2)/s.The diffusion activation energy of Fe(Ⅲ)in the molten salt is 1825.41 kJ/mol.As confirmed by XRD analysis,potentiostatic electrolysis at−0.857 V(vs.O_(2)/O_(complex)^(2-))for 6 h produces metallic iron on the cathode.展开更多
In this era of biodiversity loss and climate change,quantifying the impacts of natural disturbance on forest communities is imperative to improve biodiversity conservation efforts.Epiphytic and epixylic lichens are ef...In this era of biodiversity loss and climate change,quantifying the impacts of natural disturbance on forest communities is imperative to improve biodiversity conservation efforts.Epiphytic and epixylic lichens are effective forest quality bioindicators,as they are generally long-lived organisms supported by continuity of specific forest structures and their associated microclimatic features.However,how lichen communities respond to the effects of fluctuating historical disturbances remains unclear.Using a dendrochronological approach,this study investigates how natural disturbance dynamics indirectly influence various lichen community metrics in some of Europe's best-preserved primary mixed-beech forests.Mixed modelling revealed that natural historical disturbance processes have decades-long effects on forest structural attributes,which had both congruent and divergent impacts on lichen community richness and composition.Total species richness indirectly benefited from both historical and recent higher-severity disturbances via increased standing dead tree basal area and canopy openness respectively-likely through the presence of both pioneer and late-successional species associated with these conditions.Red-listed species richness showed a dependence on habitat continuity(old trees),and increased with disturbance-related structures(standing dead trees)whilst simultaneously benefiting from periods without severe disturbance events(old trees and reduced deadwood volume).However,if the disturbance occurred over a century in the past,no substantial effect on forest structure was detected.Therefore,while disturbance-mediated forest structures can promote overall richness,threatened species appear vulnerable to more severe disturbance events-a concern,as disturbances are predicted to intensify with climate change.Additionally,the high number of threatened species found reinforce the critical role of primary forest structural attributes for biodiversity maintenance.Hence,we recommend a landscape-scale conservation approach encompassing forest patches in different successional stages to support diverse lichen communities,and the consideration of long-term disturbance dynamics in forest conservation efforts,as they provide critical insights for safeguarding biodiversity in our changing world.展开更多
In this study,we present an investigation of the newly discovered dwarf nova ASASSN-19oc during its superoutburst on 2019 June 2.We carried out detailed UBVRcIc-photometric observations and also obtained a spectrum on...In this study,we present an investigation of the newly discovered dwarf nova ASASSN-19oc during its superoutburst on 2019 June 2.We carried out detailed UBVRcIc-photometric observations and also obtained a spectrum on day 7 of the outburst,which shows the presence of hydrogen absorption lines commonly found in dwarf nova outbursts.Analysis of photometric data reveals the occurrence of early superhumps in the initial days of observations,followed by ordinary and late superhumps.We have accurately calculated the period of the ordinary superhumps as Pord=0.05681(10)days and determined the periods at different stages,as well as the rate of change of the superhump period(P_(dot)=(5)P/P=8.1×10^(-5)).Additionally,we have derived the mass ratio of the components(q=0.09),and estimated the color temperature during the outburst as~11,000 K,the distance to the system(d=560 pc)and absolute magnitude of the system in outburst(MV=5.3).We have shown that outbursts of this star are very rare:based on brightness measurements on 600 archival photographic plates,we found only one outburst that occurred in 1984.This fact,as well as the properties listed above,convincingly shows that the variable ASASSN-19oc is a dwarf nova of WZ Sge type.展开更多
In 2020,Kostic1 published commentary on the bacterial genus Veillonella associated with the interaction between the intestinal microbiota and skeletal muscle.Since then,novel perspectives on the bidirectional gut-musc...In 2020,Kostic1 published commentary on the bacterial genus Veillonella associated with the interaction between the intestinal microbiota and skeletal muscle.Since then,novel perspectives on the bidirectional gut-muscle communication axis have gained a lot of attention.The purpose of this commentary is to explore some of the challenging issues presented in Scheiman et al.展开更多
The aim of the paper is to analyze a possible teleconnection of Quasi-Biennial Oscillation (QBO), Southern Oscillation (SO), North Atlantic Oscillation (NAO), and Arctic Oscillation (AO) phenomena with longter...The aim of the paper is to analyze a possible teleconnection of Quasi-Biennial Oscillation (QBO), Southern Oscillation (SO), North Atlantic Oscillation (NAO), and Arctic Oscillation (AO) phenomena with longterm streamflow fluctuation of the Bela River (1895-2004) and Cierny Hron River (1931-2004) (central Slovakia). Homogeneity, long-term trends, as well as inter-annual dry and wet cycles were analyzed for the entire 1895-2004 time series of the Bela River and for the 1931-2004 time series of the Cierny Hron River. Inter-annual fluctuation of the wet and dry periods was identified using spectral analysis. The most significant period is that of 3.6 years. Other significant periods are those of 2.35 years, 13.5 years, and 21 years. Since these periods were found in other rivers of the world, as well as in SO, NAO, and AO phenomena, they can be considered as relating to the general regularity of the Earth.展开更多
This study presents a methodology for assessment of the condition of hiking trails(HTs) and their impact zones in the central part of the Low Tatra mountain range, based on comparison of two complex data sets gathered...This study presents a methodology for assessment of the condition of hiking trails(HTs) and their impact zones in the central part of the Low Tatra mountain range, based on comparison of two complex data sets gathered in 33 years apart. The first field investigation was performed in 1980 and 1981, and the second in 2013 and 2014. The main goal was to perform a landscape typology in order to assess the susceptibility of landscape complexes to occurrence of anthropogenic and natural destruction processes and to assess the condition and prospects of HTs and their impacts on the adjacent alpine environment. Landscape complexes were characterised by selected abiotic, biotic and technical parameters of HTs and their impact zones. Due to the high variability of these parameters over the length of the HTs, we had to decide on how to map them. This was done using a square grid with 100 m-sized cells. For each cell with HT, the parameters were assigned the typical value within that cell. In total, 26.3 km of HT were studied, stretching over 266 grid cells. On comparison of the two data sets, it was seen that, 64%(171 grid cells) display a generally positive condition, with 54%(143 grid cells) even exhibiting significant improvement or continuously positive state of their condition. 36%(95 grid cells) were in bad condition, including 3%(9 grid cells) whose state had deteriorated, and 2%(6 grid cells) whose state had significantly deteriorated, in the time between the two assessments.展开更多
This paper presents the changes of landscape structure in the Demanovská Valley which ranks among the most valuable protected areas of Slovakia. The area was selected on the basis of changes associated with the r...This paper presents the changes of landscape structure in the Demanovská Valley which ranks among the most valuable protected areas of Slovakia. The area was selected on the basis of changes associated with the rapidly growing tourism industry and the rise of an important destination in the center of Low Tatras National Park, Slovakia. To document any changes, we visually interpreted data from aerial and satellite images in three periods(1949, 2007 and 2013) and for predicting future changes we used land use planning documentation. Interpreted data were analyzed using overlay analysis and landscape metrics. Results showed extensive changes in the landscape structure mainly connected with the development of tourism infrastructure. We also identified long-term changes whose causes stem from the transformation of society and forest management in the past. The dynamics and extent of these changes may increase in the future. We propose to stop future development of ski slopes and expansion of related infrastructure, to focus on sustainability and environmentally friendly operation of the existing ski resort and to invest a substantial portion of profits to support projects aimed to preserve surrounding lands and wildlife.展开更多
The contribution of this paper is threefold. Firstly, it develops a typology of corporate group development in terms of the pattern of corporate group formation in the Czech Republic and Slovakia. It identifies briefl...The contribution of this paper is threefold. Firstly, it develops a typology of corporate group development in terms of the pattern of corporate group formation in the Czech Republic and Slovakia. It identifies briefly three important types of corporate groups--industrial groups (type I groups), pyramid-like (type II) groups, and financial (type IIl or FIGs) groups. Using original typology for corporate groups, the paper examines development trajectory of some of the biggest FIGs and shows what effects their existence have in the two economies. Finally, some lessons resulting from this corporate group-related type of ownership concentration for other pre-transitive countries are mentioned.展开更多
Background:The use of industrial by-products rich in bioactive compounds as animal feeds can reduce greenhouse gas production.Paulownia leaves silage(PLS)was supplemented to dairy cows'diet and evaluated in vitro(...Background:The use of industrial by-products rich in bioactive compounds as animal feeds can reduce greenhouse gas production.Paulownia leaves silage(PLS)was supplemented to dairy cows'diet and evaluated in vitro(Exp.1;Rusitec)and in vivo(Exp.2,cannulated lactating dairy cows and Exp.3,non-cannulated lactating dairy cows).The study investigated the PLS effect on ruminal fermentation,microbial populations,methane production and concentration,dry matter intake(DMI),and fatty acid(FA)proportions in ruminal fluid and milk.Results:Several variables of the ruminal fluid were changed in response to the inclusion of PLS.In Exp.1,the p H increased linearly and quadratically,whereas ammonia and total volatile fatty acid(VFA)concentrations increased linearly and cubically.A linear,quadratic,and cubical decrease in methane concentration was observed with increasing dose of the PLS.Exp.2 revealed an increase in ruminal p H and ammonia concentrations,but no changes in total VFA concentration.Inclusion of PLS increased ruminal propionate(at 3 h and 6 h after feeding),isovalerate,and valerate concentrations.Addition of PLS also affected several populations of the analyzed microorganisms.The abundances of protozoa and bacteria were increased,whereas the abundance of archaea were decreased by PLS.Methane production decreased by 11%and 14%in PLS-fed cows compared to the control in Exp.2 and 3,respectively.Exp.3 revealed a reduction in the milk protein and lactose yield in the PLS-fed cows,but no effect on DMI and energy corrected milk yield.Also,the PLS diet affected the ruminal biohydrogenation process with an increased proportions of C18:3 cis-9 cis-12 cis-15,conjugated linoleic acid,C18:1 trans-11 FA,polyunsaturated fatty acids(PUFA),and reduced n6/n3 ratio and saturated fatty acids(SFA)proportion in milk.The relative transcript abundances of the 5 of 6 analyzed genes regulating FA metabolism increased.Conclusions:The dietary PLS replacing the alfalfa silage at 60 g/kg diet can reduce the methane emission and improve milk quality with greater proportions of PUFA,including conjugated linoleic acid,and C18:1 trans-11 along with reduction of SFA.展开更多
Background : Information obtained from arterial pulse waveforms (APW) can be usefulfor characterizing the cardiovascular system. To achieve this, it is necessary to know thedetailed characteristics of APWs in differen...Background : Information obtained from arterial pulse waveforms (APW) can be usefulfor characterizing the cardiovascular system. To achieve this, it is necessary to know thedetailed characteristics of APWs in different states of an organism, which would allowAPW parameters (APW- Ps) to be assigned to particular (patho)physiological conditions.Therefore, our work aimed to characterize 35 APW- Ps in rats under the influence ofisoflurane (ISO) and Zoletil/xylazine (ZO/XY) anesthesia and to study the effect of rootextract from Acanthopanax senticosus (ASRE) in these anesthetic conditions.Methods : The right jugular vein of anesthetized rats was cannulated for the administrationof ASRE and the left carotid artery for the detection of APWs from which 35APW- Ps were evaluated.Results : We obtained data on 35 APW- Ps, which significantly depended on the anesthesia,and thus, they characterized the cardiovascular system under these two conditions.ASRE transiently modulated all 35 APW- Ps, including a transient decrease insystolic and diastolic blood pressure (BP) and heart rate or increases in pulse BP, d P /d t max , and systolic and diastolic areas. Whereas the transient effects of ASRE weresimilar, the extract had prolonged disturbing effects on the cardiovascular system inrats under ZO/XY but not under ISO anesthesia. This negative effect can result fromthe disturbance caused by ZO/XY anesthesia on the cardiovascular system.Conclusions : We characterized 35 APW- Ps of rats under ISO and ZO/XY anesthesiaand found that ASRE contains compounds that can modulate the properties of thecardiovascular system, which significantly depended on the status of the cardiovascularsystem. This should be considered when using ASRE as a nutritional supplementby individuals with cardiovascular problems.展开更多
In South-Eastern forests of France,risks linked to the effects of tropospheric ozone(O_(3))are real;its annual impact has been observed specifically near the coastline and in high altitude mountains during the period ...In South-Eastern forests of France,risks linked to the effects of tropospheric ozone(O_(3))are real;its annual impact has been observed specifically near the coastline and in high altitude mountains during the period 2017-2019.In this study,the risk assessment of O_(3)pollutant was carried out using two approaches based on forest response indicators such as O_(3)specific foliar visible injury and by stomatal O_(3)flux.Phytotoxic O_(3)dose values(POD_(0))were obtained by the DO_(3)SE model.The model requires hourly O_(3)concentration for POD_(0)calculation.A modified approach that uses measurements from passive samplers(monthly average O_(3)concentration)was tested for the calculation of POD_(0)and test results showed good agreement with the POD_(0)calculated using hourly O_(3)data.In the model input file,the average O_(3)concentration is used for POD_(0),and this could be useful for POD_(0)calculation when the active monitor is limited.In this study,a flux-based assessment provided better correlation with O_(3)specific leaf injury,which is also species-specific.Foliar visible injury in response to O_(3)indicates that Pinus cembra and Pinus halepensis are more affected and therefore more sensitive than Pinus sylvestris.The POD_(0)and stomatal conductance(Gsto)seem to be induced by environmental factors,primarily rainfall and the soil water potential(fSWP).The correlation between the O_(3)flux metric and environmental variables with forest response indicators by Spearman rank test confirms P.cembra as one of the most sensitive species to O_(3).展开更多
The seasonal development of the phytoplankton, phytobenthos, zooplankton, and microbenthos in a high eutrophised intravilan water reservoir was studied. Finally, 25 genera with 44 species of Cyanobacteria/Cyanophytes ...The seasonal development of the phytoplankton, phytobenthos, zooplankton, and microbenthos in a high eutrophised intravilan water reservoir was studied. Finally, 25 genera with 44 species of Cyanobacteria/Cyanophytes and 67 genera with 102 species as well as infraspecific taxa of different groups of microscopic algae were identified. The phytoplankton in most parts of the water basin was strongly dominated by green colonial alga Golenkiniopsis longispina. From October until December a cyanophyte species Aphanocapsa delicatissima with typical cell dimensions of picoplankton/ was found in large amounts/predominated. As early as spring, a plankton bloom in all its components was observed. At that time, also a high concentration of total phosphorus was recorded, which in the second half of April dropped rapidly. The concentration of chlorophyll-a increased from 162.7 μg/L in March to 2322 μg/L in September. Massive occurrence of benthic protozoa in the plankton, as a consequence of anoxia, has been observed. Further, the detritivore and omnivore ciliate species Coleps hirtus dominated in the microbenthos. Altogether 74 of ciliate taxa were detected. Their abundance and biomass reached peak in April, but these steadily decreased from May until the end of the year. Extreme values of zooplankton density (54,016 ind/L) were recorded in spring followed by a sudden fall in summer and autumn. The contribution of rotifers (Brachionus spp., Filinia longiseta) in the total zooplankton density and biomass was 98%. Relatively a low species richness of crustaceans (4 Cladocera and 3 Copepoda) was observed.展开更多
The stability of monocultural,even-aged spruce forests at lower altitudes in Central Europe is seriously threatened by the prospects of global climate change.The thermostability and water use efficiency of their photo...The stability of monocultural,even-aged spruce forests at lower altitudes in Central Europe is seriously threatened by the prospects of global climate change.The thermostability and water use efficiency of their photo synthetic apparatus might play a vital role in their successful acclimation.In this study,photo systemⅡ(PSⅡ)performance(OJIP transient,rapid light curves)and thermostability were analyzed in Norway spruce(Picea abies(L.)Karst.)throughout the growing season of the exceptionally warm year 2018(May-September)in the Western Carpathians,Slovakia.These measurements were accompanied by analysis of pigment concentrations in the needles.In addition,gas-exchange temperature curves were produced weekly from June until September to obtain intrinsic water use efficiencies.At the beginning of the growing season,needles exposed to heat stress showed significantly higher basal fluorescence and lower quantum yield,performance index,critical temperature thresholds of PSII inactivation and nonphotochemical yield in comparison to other months.The overall thermostability(heat-resistance)of PSII peaked in July and August,reflected in the lowest basal fluorescence and the highest quantum yield of PSII,critical temperature thresholds and yield of non-photochemical quenching under heat stress.Additionally,the ratio between chlorophyll and carotenoids was the highest in August and had a positive impact on PSII thermostability.Moreover,the high-temperature intrinsic water use efficiency was significantly higher during July and August than in June.Results show that15-year-old trees of Picea abies at 840 m a.s.l.exhibited acclimative seasonal responses of PSII thermostability and intrinsic water use efficiency during an exceptionally warm year.Our results suggest that mountainous P.abies at lower altitudes can acclimate their photosynthetic apparatus to higher temperatures during summer.展开更多
Electrical conductivity of molten binary and ternary mixtures based on the system NaF-AlF3-SiO2 was investigated by means of a tube–cell (made of pyrolytic boron nitride) with stationary electrodes. Viscosity of th...Electrical conductivity of molten binary and ternary mixtures based on the system NaF-AlF3-SiO2 was investigated by means of a tube–cell (made of pyrolytic boron nitride) with stationary electrodes. Viscosity of the binary system Na3AlF6-SiO2 was measured by computerized torsion pendulum method. It was found that conductivity and viscosity varied linearly with temperature in all investigated mixtures. Obtained content dependence of electrical conductivity (isotherms) was divided into two parts. First, one represented the content region up to 10%(mole fraction) of SiO2;second, the region was with a higher content of SiO2 (from 10%up to 40%). While the conductivity considerably decreased with content of SiO2 in the second part; it surprisingly rose in the low content range. A small addition of SiO2 to the molten cryolite (up to 10%) could slightly increase viscosity, but had no influence on the slope of this dependence since it is responsible for a glassy-networks formation in the melt. Further addition of SiO2 to the molten cryolite had a huge effect on the viscosity.展开更多
AIM To identify the effect of hydrogen-rich water(HRW) and electrolyzed-alkaline water(EAW) on high-fat-induced non-alcoholic fatty acid disease in mice.METHODS Mice were divided into four groups:(1) Regular diet(RD)/...AIM To identify the effect of hydrogen-rich water(HRW) and electrolyzed-alkaline water(EAW) on high-fat-induced non-alcoholic fatty acid disease in mice.METHODS Mice were divided into four groups:(1) Regular diet(RD)/regular water(RW);(2) high-fat diet(HFD)/RW;(3) RD/EAW; and(4) HFD/EAW. Weight and body composition were measured. After twelve weeks, animals were sacrificed, and livers were processed for histology and reverse-transcriptase polymerase chain reaction. A similar experiment was performed using HRW to determine the influence and importance of molecular hydrogen(H2) in EAW. Finally, we compared the response of hepatocytes isolated from mice drinking HRW or RW to palmitate overload.RESULTS EAW had several properties important to the study:(1) pH = 11;(2) oxidation-reduction potential of-495 mV; and(3) H2 = 0.2 mg/L. However, in contrast to other studies, there were no differences between the groups drinking EAW or RW in either the RD or HFD groups. We hypothesized that the null result was due to low H2 concentrations. Therefore, we evaluated the effects of RW and low and high HRW concentrations(L-HRW = 0.3 mg H2/L and H-HRW = 0.8 mg H2/L, respectively) in mice fed an HFD. Compared to RW and L-HRW, H-HRW resulted in a lower increase in fat mass(46% vs 61%), an increase in lean body mass(42% vs 28%), and a decrease in hepatic lipid accumulation(P < 0.01). Lastly, exposure of hepatocytes isolated from mice drinking H-HRW to palmitate overload demonstrated a protective effect from H2 by reducing hepatocyte lipid accumulation in comparison to mice drinking regular water.CONCLUSION H2 is the therapeutic agent in electrolyzed-alkaline water and attenuates HFD-induced nonalcoholic fatty liver disease in mice.展开更多
The use of mechanical activation to enhance gold recovery from a CuPbZn complex sulfide concentrate was investigated. The effects of milling time, ball size, sample to ball ratio and milling speed on thiosulfate leach...The use of mechanical activation to enhance gold recovery from a CuPbZn complex sulfide concentrate was investigated. The effects of milling time, ball size, sample to ball ratio and milling speed on thiosulfate leaching were studied. Under optimum conditions of milling time 1 h, ball size 20 mm, sample to ball ratio 1/15 and mill speed 600 r/min, nearly 78% of sample is amorphized, particle size decreases from d100=30 μm to d100=8 μm, specific surface area increases from 1.3 m2/g to 4.6 m2/g and gold recovery enhances from 17.4 % in non-activated sample to 73.26 %.展开更多
Insufficient growth and rarefaction of capillaries, followed by endothelial dysfunction may represent one of the most critical mechanisms involved in heart damage. In this study we examined histochemical and ultrastru...Insufficient growth and rarefaction of capillaries, followed by endothelial dysfunction may represent one of the most critical mechanisms involved in heart damage. In this study we examined histochemical and ultrastructural changes in myocardial capillary endothelium in two models of heart failure streptozotocin-induced diabetes mellitus (STZ) and NO-deficient hypertension in male Wistar rats. Diabetes was induced by a single i.v. dose of STZ (45 mg/kg) and chronic 9-week stage was analysed. To induce NO-deficient hypertension, animals were treated with inhibitor of NO synthase Lnitroarginine methylester (L-NAME) (40 mg/kg) for 4 weeks. Left ventricular tissue was processed for enzyme catalytic histochemistry of capillary alkaline phosphatase (A1Ph), dipeptidyl peptidase IV (DPP IV), and endothelial NO synthase/NADPH-diaphorase (NOS) and for ultrastructural analysis. In diabetic and hypertensive rats, lower/absent A1Ph and DPP IV activities were found in focal micro-areas. NOS activity was significantly reduced and persisted only locally. Quantitative evaluation demonstrated reduction of reaction product intensity of A1Ph, DPP and NOS by 49.50%,74.36%, 20.05% in diabetic and 62.93%, 82.71%, 37.65% in hypertensive rats. Subcellular alterations of endothelial cells were found in heart of both groups suggesting injury of capillary function as well as compensatory processes. Endothelial injury was more significant in diabetic animals, in contrast the adaptation was more evident in hypertensive ones. Concluding: both STZ-induced diabetes- and NO-deficient hypertension-related cardiomyopathy were accompanied by similar features of structural remodelling of cardiac capillary network manifested as angiogenesis and angiopathy. The latter was however, predominant and may accelerate disappearance of capillary endothelium contributing to myocardial dysfunction.展开更多
AIM:To analyze possible relationships between CA IX/ CA XII and pVHL expression in normal and neoplastic colorectal mucosa. METHODS: Immunohistochemical staining of 42 tissue specimens obtained from 17 cancer patients...AIM:To analyze possible relationships between CA IX/ CA XII and pVHL expression in normal and neoplastic colorectal mucosa. METHODS: Immunohistochemical staining of 42 tissue specimens obtained from 17 cancer patients was performed to evaluate the distribution and semi-quantitatively assess the levels of CA IX, CA XII and pVHL. VHL mRNAs from 14 fresh-frozen tumors was amplified by RT-PCR and subjected to sequencing. CA9 and G412mRNA levels were analyzed by semi-quantitative RT-PCR in comparison with VEGFas an indicator of hypoxia that uncouples the pVHL control. RESULTS: Tumor tissues were associated with a borderline increase of CA IX staining signal and slight but significant decrease of CA XII immunoreactivity, whereas no association was found for pVHL. Sequence analysis of RT-PCR-amplified VHL mRNAs revealed no deletions/ mutations, suggesting that they were VHL-competent. We did not observe any correlation between pVHL and CA IX/CA XII proteins as well as between MEGFand CA9 mRNAs, but the tumor-associated changes in mRNA levels of VEGFand CA12 showed a significant inverse relationship. CONCLUSION: Our results indicate that CA9and CA12 are regulated by different intratumoral factors and that lack of apparent relationship between the levels of CA IX/CA XII and pVHL cannot be fully assigned to uncoupling of negative regulatory function of pVHL by tumor hypoxia signified by induced VEGF transcription. The interplay between the functional pVHL and CA IX/CA XII in colorectal tumors seems rather complex and is not evident merely at the expression levels.展开更多
Ecosystem services(ES)are highly impacted by human-induced land-use change.Progressive urbanization and agricultural land abandonment in Western Europe necessitate assessments of future land-change impacts on ES to en...Ecosystem services(ES)are highly impacted by human-induced land-use change.Progressive urbanization and agricultural land abandonment in Western Europe necessitate assessments of future land-change impacts on ES to ensure sustainable service management.The present study aims at evaluating future demand and supply of three key services(flood protection,nearby recreation and biodiversity)in the mountainous region of Vorarlberg,Austria.We mapped the ES for the referenced time step 2016 and two scenarios for 2050,assuming the continuation of current land-change trends and pressure on landscape development.Results for the referenced landscape in 2016 show the highest ES supply for intermediate levels,while ES supply was low in the lowlands and valley bottoms and in high-elevation areas.We found a high positive correlation of ES with the distribution of forested areas.In contrast,service demand was highest in lowelevation areas and decreased with increasing elevation.This indicates that densely settled and intensively used agricultural areas currently suffer from ES undersupply.The projected future development of land use showed an increase in both supply and demand of the selected ES.The overall service supply increased more than the respective demand due to some reforestation of open land.As forests were found to be important synergistic areas for overall service provision,we expect decreasing demand on related services.Locally,demand was found to exceed the supply of ES,especially in the densely populated Rhine valley-requiring further policy interventions.Such ES-related information may contribute to regional policy making and ensure the long-term provision of ESs for future generations.展开更多
Ionizing radiation caused by medical treatments,nuclear events or even space flights can irreversibly damage structure and function of brain cells.That can result in serious brain damage,with memory and behavior disor...Ionizing radiation caused by medical treatments,nuclear events or even space flights can irreversibly damage structure and function of brain cells.That can result in serious brain damage,with memory and behavior disorders,or even fatal oncologic or neurodegenerative illnesses.Currently used treatments and drugs are mostly targeting biochemical processes of cell apoptosis,radiation toxicity,neuroinflammation,and conditions such as cognitive-behavioral disturbances or others that result from the radiation insult.With most drugs,the side effects and potential toxicity are also to be considered.Therefore,many agents have not been approved for clinical use yet.In this review,we focus on the latest and most effective agents that have been used in animal and also in the human research,and clinical treatments.They could have the potential therapeutical use in cases of radiation damage of central nervous system,and also in prevention considering their radioprotecting effect of nervous tissue.展开更多
基金Project(52074084)supported by the National Natural Science Foundation of China。
文摘The high-temperature requirement for liquid iron smelting via molten oxide electrolysis presents significant challenges.This study investigates the electrochemical reduction of Fe(Ⅲ)in a novel low-temperature electrolyte,Na_(2)SiO_(3)-SiO_(2)-Fe_(2)O_(3),utilizing cyclic voltammetry and square wave voltammetry techniques.The results show that Fe(Ⅲ)reduction occurs in two steps:Fe(Ⅲ)+e^(−)→Fe(Ⅱ),Fe(Ⅱ)+2e^(−)→Fe,and that the redox process of Fe(Ⅲ)/Fe(Ⅱ)at the tungsten electrode is an irreversible reaction controlled by diffusion.The diffusion coefficients of Fe(Ⅲ)in the molten Na_(2)SiO_(3)-SiO_(2)-Fe_(2)O_(3)in the temperature range of 1248–1278 K are between 1.86×10^(−6)cm^(2)/s and 1.58×10^(−4)cm^(2)/s.The diffusion activation energy of Fe(Ⅲ)in the molten salt is 1825.41 kJ/mol.As confirmed by XRD analysis,potentiostatic electrolysis at−0.857 V(vs.O_(2)/O_(complex)^(2-))for 6 h produces metallic iron on the cathode.
基金supported by the Czech Science Foundation(grant no.GACR 22-31322S)the Czech University of Life Sciences Prague(grant no.IGA A_19_22)+3 种基金supported by the Operational Programme Integrated Infrastructure(OPII)funded by the ERDF(ITMS313011T721)Specific research PrF UHK 2114/2022 for the financial supportthe financial support of the Rita-Levi Montalcini(2019)programmefunded by the Italian Ministry of University。
文摘In this era of biodiversity loss and climate change,quantifying the impacts of natural disturbance on forest communities is imperative to improve biodiversity conservation efforts.Epiphytic and epixylic lichens are effective forest quality bioindicators,as they are generally long-lived organisms supported by continuity of specific forest structures and their associated microclimatic features.However,how lichen communities respond to the effects of fluctuating historical disturbances remains unclear.Using a dendrochronological approach,this study investigates how natural disturbance dynamics indirectly influence various lichen community metrics in some of Europe's best-preserved primary mixed-beech forests.Mixed modelling revealed that natural historical disturbance processes have decades-long effects on forest structural attributes,which had both congruent and divergent impacts on lichen community richness and composition.Total species richness indirectly benefited from both historical and recent higher-severity disturbances via increased standing dead tree basal area and canopy openness respectively-likely through the presence of both pioneer and late-successional species associated with these conditions.Red-listed species richness showed a dependence on habitat continuity(old trees),and increased with disturbance-related structures(standing dead trees)whilst simultaneously benefiting from periods without severe disturbance events(old trees and reduced deadwood volume).However,if the disturbance occurred over a century in the past,no substantial effect on forest structure was detected.Therefore,while disturbance-mediated forest structures can promote overall richness,threatened species appear vulnerable to more severe disturbance events-a concern,as disturbances are predicted to intensify with climate change.Additionally,the high number of threatened species found reinforce the critical role of primary forest structural attributes for biodiversity maintenance.Hence,we recommend a landscape-scale conservation approach encompassing forest patches in different successional stages to support diverse lichen communities,and the consideration of long-term disturbance dynamics in forest conservation efforts,as they provide critical insights for safeguarding biodiversity in our changing world.
基金financial support of the APVV-20-0148,VEGA 2/0030/21 and VEGA 2/0031/22grantssupport from the Government Office of the Slovak Republic within EU NextGenerationEU through the Recovery and Resilience Plan for Slovakia under the project No.09I03-03-V01-00002the private company 4pi Systeme GmbH for partial sponsorship。
文摘In this study,we present an investigation of the newly discovered dwarf nova ASASSN-19oc during its superoutburst on 2019 June 2.We carried out detailed UBVRcIc-photometric observations and also obtained a spectrum on day 7 of the outburst,which shows the presence of hydrogen absorption lines commonly found in dwarf nova outbursts.Analysis of photometric data reveals the occurrence of early superhumps in the initial days of observations,followed by ordinary and late superhumps.We have accurately calculated the period of the ordinary superhumps as Pord=0.05681(10)days and determined the periods at different stages,as well as the rate of change of the superhump period(P_(dot)=(5)P/P=8.1×10^(-5)).Additionally,we have derived the mass ratio of the components(q=0.09),and estimated the color temperature during the outburst as~11,000 K,the distance to the system(d=560 pc)and absolute magnitude of the system in outburst(MV=5.3).We have shown that outbursts of this star are very rare:based on brightness measurements on 600 archival photographic plates,we found only one outburst that occurred in 1984.This fact,as well as the properties listed above,convincingly shows that the variable ASASSN-19oc is a dwarf nova of WZ Sge type.
基金supported by Grant No.APVV-17-0099 and Grant No.APVV-22-0047(VB)of the Slovak ResearchDevelopment Agency,Grant No.VEGA 1/0260/21(VB)Sportdiag team o.z.
文摘In 2020,Kostic1 published commentary on the bacterial genus Veillonella associated with the interaction between the intestinal microbiota and skeletal muscle.Since then,novel perspectives on the bidirectional gut-muscle communication axis have gained a lot of attention.The purpose of this commentary is to explore some of the challenging issues presented in Scheiman et al.
文摘The aim of the paper is to analyze a possible teleconnection of Quasi-Biennial Oscillation (QBO), Southern Oscillation (SO), North Atlantic Oscillation (NAO), and Arctic Oscillation (AO) phenomena with longterm streamflow fluctuation of the Bela River (1895-2004) and Cierny Hron River (1931-2004) (central Slovakia). Homogeneity, long-term trends, as well as inter-annual dry and wet cycles were analyzed for the entire 1895-2004 time series of the Bela River and for the 1931-2004 time series of the Cierny Hron River. Inter-annual fluctuation of the wet and dry periods was identified using spectral analysis. The most significant period is that of 3.6 years. Other significant periods are those of 2.35 years, 13.5 years, and 21 years. Since these periods were found in other rivers of the world, as well as in SO, NAO, and AO phenomena, they can be considered as relating to the general regularity of the Earth.
基金part of the project Green Infrastructure of Slovakia(Grant No.2/0066/15)from the Scientific Grant Agency of the Ministry of Education of the Slovak Republic and the Slovak Academy of Sciences
文摘This study presents a methodology for assessment of the condition of hiking trails(HTs) and their impact zones in the central part of the Low Tatra mountain range, based on comparison of two complex data sets gathered in 33 years apart. The first field investigation was performed in 1980 and 1981, and the second in 2013 and 2014. The main goal was to perform a landscape typology in order to assess the susceptibility of landscape complexes to occurrence of anthropogenic and natural destruction processes and to assess the condition and prospects of HTs and their impacts on the adjacent alpine environment. Landscape complexes were characterised by selected abiotic, biotic and technical parameters of HTs and their impact zones. Due to the high variability of these parameters over the length of the HTs, we had to decide on how to map them. This was done using a square grid with 100 m-sized cells. For each cell with HT, the parameters were assigned the typical value within that cell. In total, 26.3 km of HT were studied, stretching over 266 grid cells. On comparison of the two data sets, it was seen that, 64%(171 grid cells) display a generally positive condition, with 54%(143 grid cells) even exhibiting significant improvement or continuously positive state of their condition. 36%(95 grid cells) were in bad condition, including 3%(9 grid cells) whose state had deteriorated, and 2%(6 grid cells) whose state had significantly deteriorated, in the time between the two assessments.
基金the support of the Scientific Grant Agency of the Slovak Republic through the research grant:"Adaptation strategies to natural and social disturbancies in the forestlandscape"(no.2/0038/14)
文摘This paper presents the changes of landscape structure in the Demanovská Valley which ranks among the most valuable protected areas of Slovakia. The area was selected on the basis of changes associated with the rapidly growing tourism industry and the rise of an important destination in the center of Low Tatras National Park, Slovakia. To document any changes, we visually interpreted data from aerial and satellite images in three periods(1949, 2007 and 2013) and for predicting future changes we used land use planning documentation. Interpreted data were analyzed using overlay analysis and landscape metrics. Results showed extensive changes in the landscape structure mainly connected with the development of tourism infrastructure. We also identified long-term changes whose causes stem from the transformation of society and forest management in the past. The dynamics and extent of these changes may increase in the future. We propose to stop future development of ski slopes and expansion of related infrastructure, to focus on sustainability and environmentally friendly operation of the existing ski resort and to invest a substantial portion of profits to support projects aimed to preserve surrounding lands and wildlife.
文摘The contribution of this paper is threefold. Firstly, it develops a typology of corporate group development in terms of the pattern of corporate group formation in the Czech Republic and Slovakia. It identifies briefly three important types of corporate groups--industrial groups (type I groups), pyramid-like (type II) groups, and financial (type IIl or FIGs) groups. Using original typology for corporate groups, the paper examines development trajectory of some of the biggest FIGs and shows what effects their existence have in the two economies. Finally, some lessons resulting from this corporate group-related type of ownership concentration for other pre-transitive countries are mentioned.
基金a grant from the National Science Center,Poland(Grant No.2016/23/B/NZ9/03427)co-financed within the framework of the Polish Ministry of Science and Higher Education’s program:“Regional Initiative Excellence”in the years 2019–2022(No.005/RID/2018/19)“financing amount 12000000,00 PLN”。
文摘Background:The use of industrial by-products rich in bioactive compounds as animal feeds can reduce greenhouse gas production.Paulownia leaves silage(PLS)was supplemented to dairy cows'diet and evaluated in vitro(Exp.1;Rusitec)and in vivo(Exp.2,cannulated lactating dairy cows and Exp.3,non-cannulated lactating dairy cows).The study investigated the PLS effect on ruminal fermentation,microbial populations,methane production and concentration,dry matter intake(DMI),and fatty acid(FA)proportions in ruminal fluid and milk.Results:Several variables of the ruminal fluid were changed in response to the inclusion of PLS.In Exp.1,the p H increased linearly and quadratically,whereas ammonia and total volatile fatty acid(VFA)concentrations increased linearly and cubically.A linear,quadratic,and cubical decrease in methane concentration was observed with increasing dose of the PLS.Exp.2 revealed an increase in ruminal p H and ammonia concentrations,but no changes in total VFA concentration.Inclusion of PLS increased ruminal propionate(at 3 h and 6 h after feeding),isovalerate,and valerate concentrations.Addition of PLS also affected several populations of the analyzed microorganisms.The abundances of protozoa and bacteria were increased,whereas the abundance of archaea were decreased by PLS.Methane production decreased by 11%and 14%in PLS-fed cows compared to the control in Exp.2 and 3,respectively.Exp.3 revealed a reduction in the milk protein and lactose yield in the PLS-fed cows,but no effect on DMI and energy corrected milk yield.Also,the PLS diet affected the ruminal biohydrogenation process with an increased proportions of C18:3 cis-9 cis-12 cis-15,conjugated linoleic acid,C18:1 trans-11 FA,polyunsaturated fatty acids(PUFA),and reduced n6/n3 ratio and saturated fatty acids(SFA)proportion in milk.The relative transcript abundances of the 5 of 6 analyzed genes regulating FA metabolism increased.Conclusions:The dietary PLS replacing the alfalfa silage at 60 g/kg diet can reduce the methane emission and improve milk quality with greater proportions of PUFA,including conjugated linoleic acid,and C18:1 trans-11 along with reduction of SFA.
基金Agency of the Slovak Republic,Grant/Award Number:2/0023/22,2/0066/23 and 2/0091/21Slovak Research&Development Agency,Grant/Award Number:APVV-19-0154 and APVV-22-0154。
文摘Background : Information obtained from arterial pulse waveforms (APW) can be usefulfor characterizing the cardiovascular system. To achieve this, it is necessary to know thedetailed characteristics of APWs in different states of an organism, which would allowAPW parameters (APW- Ps) to be assigned to particular (patho)physiological conditions.Therefore, our work aimed to characterize 35 APW- Ps in rats under the influence ofisoflurane (ISO) and Zoletil/xylazine (ZO/XY) anesthesia and to study the effect of rootextract from Acanthopanax senticosus (ASRE) in these anesthetic conditions.Methods : The right jugular vein of anesthetized rats was cannulated for the administrationof ASRE and the left carotid artery for the detection of APWs from which 35APW- Ps were evaluated.Results : We obtained data on 35 APW- Ps, which significantly depended on the anesthesia,and thus, they characterized the cardiovascular system under these two conditions.ASRE transiently modulated all 35 APW- Ps, including a transient decrease insystolic and diastolic blood pressure (BP) and heart rate or increases in pulse BP, d P /d t max , and systolic and diastolic areas. Whereas the transient effects of ASRE weresimilar, the extract had prolonged disturbing effects on the cardiovascular system inrats under ZO/XY but not under ISO anesthesia. This negative effect can result fromthe disturbance caused by ZO/XY anesthesia on the cardiovascular system.Conclusions : We characterized 35 APW- Ps of rats under ISO and ZO/XY anesthesiaand found that ASRE contains compounds that can modulate the properties of thecardiovascular system, which significantly depended on the status of the cardiovascularsystem. This should be considered when using ASRE as a nutritional supplementby individuals with cardiovascular problems.
基金funded by the Alcotra program MITIMPACT(Grand No.1671/1450109240)the Scientific Grant Agency of the Slovak Republic,VEGA(Project No.2/0093/2)。
文摘In South-Eastern forests of France,risks linked to the effects of tropospheric ozone(O_(3))are real;its annual impact has been observed specifically near the coastline and in high altitude mountains during the period 2017-2019.In this study,the risk assessment of O_(3)pollutant was carried out using two approaches based on forest response indicators such as O_(3)specific foliar visible injury and by stomatal O_(3)flux.Phytotoxic O_(3)dose values(POD_(0))were obtained by the DO_(3)SE model.The model requires hourly O_(3)concentration for POD_(0)calculation.A modified approach that uses measurements from passive samplers(monthly average O_(3)concentration)was tested for the calculation of POD_(0)and test results showed good agreement with the POD_(0)calculated using hourly O_(3)data.In the model input file,the average O_(3)concentration is used for POD_(0),and this could be useful for POD_(0)calculation when the active monitor is limited.In this study,a flux-based assessment provided better correlation with O_(3)specific leaf injury,which is also species-specific.Foliar visible injury in response to O_(3)indicates that Pinus cembra and Pinus halepensis are more affected and therefore more sensitive than Pinus sylvestris.The POD_(0)and stomatal conductance(Gsto)seem to be induced by environmental factors,primarily rainfall and the soil water potential(fSWP).The correlation between the O_(3)flux metric and environmental variables with forest response indicators by Spearman rank test confirms P.cembra as one of the most sensitive species to O_(3).
基金supported by APVV,project No.0566-07,VEGA projects No.1/0600/11 and 2/0113/13Comenius University in Bratislava Science Park supported by the Research and Development Operational Programme funded by the ERDF Grant number:ITMS 26240220086supported by the project ITMS:26240220049.
文摘The seasonal development of the phytoplankton, phytobenthos, zooplankton, and microbenthos in a high eutrophised intravilan water reservoir was studied. Finally, 25 genera with 44 species of Cyanobacteria/Cyanophytes and 67 genera with 102 species as well as infraspecific taxa of different groups of microscopic algae were identified. The phytoplankton in most parts of the water basin was strongly dominated by green colonial alga Golenkiniopsis longispina. From October until December a cyanophyte species Aphanocapsa delicatissima with typical cell dimensions of picoplankton/ was found in large amounts/predominated. As early as spring, a plankton bloom in all its components was observed. At that time, also a high concentration of total phosphorus was recorded, which in the second half of April dropped rapidly. The concentration of chlorophyll-a increased from 162.7 μg/L in March to 2322 μg/L in September. Massive occurrence of benthic protozoa in the plankton, as a consequence of anoxia, has been observed. Further, the detritivore and omnivore ciliate species Coleps hirtus dominated in the microbenthos. Altogether 74 of ciliate taxa were detected. Their abundance and biomass reached peak in April, but these steadily decreased from May until the end of the year. Extreme values of zooplankton density (54,016 ind/L) were recorded in spring followed by a sudden fall in summer and autumn. The contribution of rotifers (Brachionus spp., Filinia longiseta) in the total zooplankton density and biomass was 98%. Relatively a low species richness of crustaceans (4 Cladocera and 3 Copepoda) was observed.
基金the Ministry of Education,Youth and Sports of CR within the CzeCOS program(grant number LM2018123)the Slovak Grant Agency for Science(no.VEGA 1/0535/20)+1 种基金Slovak Research and Development Agency(APVV-17-0644)project FORRES,ITMS:313011T678(20%)supported by the Operational Programme Integrated Infrastructure(OPII)funded by the ERDF。
文摘The stability of monocultural,even-aged spruce forests at lower altitudes in Central Europe is seriously threatened by the prospects of global climate change.The thermostability and water use efficiency of their photo synthetic apparatus might play a vital role in their successful acclimation.In this study,photo systemⅡ(PSⅡ)performance(OJIP transient,rapid light curves)and thermostability were analyzed in Norway spruce(Picea abies(L.)Karst.)throughout the growing season of the exceptionally warm year 2018(May-September)in the Western Carpathians,Slovakia.These measurements were accompanied by analysis of pigment concentrations in the needles.In addition,gas-exchange temperature curves were produced weekly from June until September to obtain intrinsic water use efficiencies.At the beginning of the growing season,needles exposed to heat stress showed significantly higher basal fluorescence and lower quantum yield,performance index,critical temperature thresholds of PSII inactivation and nonphotochemical yield in comparison to other months.The overall thermostability(heat-resistance)of PSII peaked in July and August,reflected in the lowest basal fluorescence and the highest quantum yield of PSII,critical temperature thresholds and yield of non-photochemical quenching under heat stress.Additionally,the ratio between chlorophyll and carotenoids was the highest in August and had a positive impact on PSII thermostability.Moreover,the high-temperature intrinsic water use efficiency was significantly higher during July and August than in June.Results show that15-year-old trees of Picea abies at 840 m a.s.l.exhibited acclimative seasonal responses of PSII thermostability and intrinsic water use efficiency during an exceptionally warm year.Our results suggest that mountainous P.abies at lower altitudes can acclimate their photosynthetic apparatus to higher temperatures during summer.
基金supported by the Science and Technology Assistance Agency (APVV-0460-10 and SK-CN-0029-12)Slovak Grant Agency (VEGA 2/0116/14 and VEGA 2/0095/12)+2 种基金the National Natural Science Foundation of China (51322406)the Program for New Century Excellent Talents (NCET-13-0107)Ministry of Education of China
文摘Electrical conductivity of molten binary and ternary mixtures based on the system NaF-AlF3-SiO2 was investigated by means of a tube–cell (made of pyrolytic boron nitride) with stationary electrodes. Viscosity of the binary system Na3AlF6-SiO2 was measured by computerized torsion pendulum method. It was found that conductivity and viscosity varied linearly with temperature in all investigated mixtures. Obtained content dependence of electrical conductivity (isotherms) was divided into two parts. First, one represented the content region up to 10%(mole fraction) of SiO2;second, the region was with a higher content of SiO2 (from 10%up to 40%). While the conductivity considerably decreased with content of SiO2 in the second part; it surprisingly rose in the low content range. A small addition of SiO2 to the molten cryolite (up to 10%) could slightly increase viscosity, but had no influence on the slope of this dependence since it is responsible for a glassy-networks formation in the melt. Further addition of SiO2 to the molten cryolite had a huge effect on the viscosity.
基金Tel Hai College Research funding Grant,No.25-2-14-114
文摘AIM To identify the effect of hydrogen-rich water(HRW) and electrolyzed-alkaline water(EAW) on high-fat-induced non-alcoholic fatty acid disease in mice.METHODS Mice were divided into four groups:(1) Regular diet(RD)/regular water(RW);(2) high-fat diet(HFD)/RW;(3) RD/EAW; and(4) HFD/EAW. Weight and body composition were measured. After twelve weeks, animals were sacrificed, and livers were processed for histology and reverse-transcriptase polymerase chain reaction. A similar experiment was performed using HRW to determine the influence and importance of molecular hydrogen(H2) in EAW. Finally, we compared the response of hepatocytes isolated from mice drinking HRW or RW to palmitate overload.RESULTS EAW had several properties important to the study:(1) pH = 11;(2) oxidation-reduction potential of-495 mV; and(3) H2 = 0.2 mg/L. However, in contrast to other studies, there were no differences between the groups drinking EAW or RW in either the RD or HFD groups. We hypothesized that the null result was due to low H2 concentrations. Therefore, we evaluated the effects of RW and low and high HRW concentrations(L-HRW = 0.3 mg H2/L and H-HRW = 0.8 mg H2/L, respectively) in mice fed an HFD. Compared to RW and L-HRW, H-HRW resulted in a lower increase in fat mass(46% vs 61%), an increase in lean body mass(42% vs 28%), and a decrease in hepatic lipid accumulation(P < 0.01). Lastly, exposure of hepatocytes isolated from mice drinking H-HRW to palmitate overload demonstrated a protective effect from H2 by reducing hepatocyte lipid accumulation in comparison to mice drinking regular water.CONCLUSION H2 is the therapeutic agent in electrolyzed-alkaline water and attenuates HFD-induced nonalcoholic fatty liver disease in mice.
基金supported by Iran Mineral Processing Research Center (IMPRC)the IMPRC for the financial support of this work
文摘The use of mechanical activation to enhance gold recovery from a CuPbZn complex sulfide concentrate was investigated. The effects of milling time, ball size, sample to ball ratio and milling speed on thiosulfate leaching were studied. Under optimum conditions of milling time 1 h, ball size 20 mm, sample to ball ratio 1/15 and mill speed 600 r/min, nearly 78% of sample is amorphized, particle size decreases from d100=30 μm to d100=8 μm, specific surface area increases from 1.3 m2/g to 4.6 m2/g and gold recovery enhances from 17.4 % in non-activated sample to 73.26 %.
文摘Insufficient growth and rarefaction of capillaries, followed by endothelial dysfunction may represent one of the most critical mechanisms involved in heart damage. In this study we examined histochemical and ultrastructural changes in myocardial capillary endothelium in two models of heart failure streptozotocin-induced diabetes mellitus (STZ) and NO-deficient hypertension in male Wistar rats. Diabetes was induced by a single i.v. dose of STZ (45 mg/kg) and chronic 9-week stage was analysed. To induce NO-deficient hypertension, animals were treated with inhibitor of NO synthase Lnitroarginine methylester (L-NAME) (40 mg/kg) for 4 weeks. Left ventricular tissue was processed for enzyme catalytic histochemistry of capillary alkaline phosphatase (A1Ph), dipeptidyl peptidase IV (DPP IV), and endothelial NO synthase/NADPH-diaphorase (NOS) and for ultrastructural analysis. In diabetic and hypertensive rats, lower/absent A1Ph and DPP IV activities were found in focal micro-areas. NOS activity was significantly reduced and persisted only locally. Quantitative evaluation demonstrated reduction of reaction product intensity of A1Ph, DPP and NOS by 49.50%,74.36%, 20.05% in diabetic and 62.93%, 82.71%, 37.65% in hypertensive rats. Subcellular alterations of endothelial cells were found in heart of both groups suggesting injury of capillary function as well as compensatory processes. Endothelial injury was more significant in diabetic animals, in contrast the adaptation was more evident in hypertensive ones. Concluding: both STZ-induced diabetes- and NO-deficient hypertension-related cardiomyopathy were accompanied by similar features of structural remodelling of cardiac capillary network manifested as angiogenesis and angiopathy. The latter was however, predominant and may accelerate disappearance of capillary endothelium contributing to myocardial dysfunction.
基金Supported by the Grants From Sigrid Juselius Foundation, from Finnish Cultural Foundation and Finnish Dental Society from the National Institutes of Health (DK40163, GM34182, and GM53405)from Slovak Grant Agency (2/2025) from the Slovak Government (Cancer Genomics SP 51/0280800) and from Bayer Corporation
文摘AIM:To analyze possible relationships between CA IX/ CA XII and pVHL expression in normal and neoplastic colorectal mucosa. METHODS: Immunohistochemical staining of 42 tissue specimens obtained from 17 cancer patients was performed to evaluate the distribution and semi-quantitatively assess the levels of CA IX, CA XII and pVHL. VHL mRNAs from 14 fresh-frozen tumors was amplified by RT-PCR and subjected to sequencing. CA9 and G412mRNA levels were analyzed by semi-quantitative RT-PCR in comparison with VEGFas an indicator of hypoxia that uncouples the pVHL control. RESULTS: Tumor tissues were associated with a borderline increase of CA IX staining signal and slight but significant decrease of CA XII immunoreactivity, whereas no association was found for pVHL. Sequence analysis of RT-PCR-amplified VHL mRNAs revealed no deletions/ mutations, suggesting that they were VHL-competent. We did not observe any correlation between pVHL and CA IX/CA XII proteins as well as between MEGFand CA9 mRNAs, but the tumor-associated changes in mRNA levels of VEGFand CA12 showed a significant inverse relationship. CONCLUSION: Our results indicate that CA9and CA12 are regulated by different intratumoral factors and that lack of apparent relationship between the levels of CA IX/CA XII and pVHL cannot be fully assigned to uncoupling of negative regulatory function of pVHL by tumor hypoxia signified by induced VEGF transcription. The interplay between the functional pVHL and CA IX/CA XII in colorectal tumors seems rather complex and is not evident merely at the expression levels.
基金the HiFlow-CMA project conducted by alpS and WSL, funded by the Austrian Climate and Energy Fund (ACRP 8th call)
文摘Ecosystem services(ES)are highly impacted by human-induced land-use change.Progressive urbanization and agricultural land abandonment in Western Europe necessitate assessments of future land-change impacts on ES to ensure sustainable service management.The present study aims at evaluating future demand and supply of three key services(flood protection,nearby recreation and biodiversity)in the mountainous region of Vorarlberg,Austria.We mapped the ES for the referenced time step 2016 and two scenarios for 2050,assuming the continuation of current land-change trends and pressure on landscape development.Results for the referenced landscape in 2016 show the highest ES supply for intermediate levels,while ES supply was low in the lowlands and valley bottoms and in high-elevation areas.We found a high positive correlation of ES with the distribution of forested areas.In contrast,service demand was highest in lowelevation areas and decreased with increasing elevation.This indicates that densely settled and intensively used agricultural areas currently suffer from ES undersupply.The projected future development of land use showed an increase in both supply and demand of the selected ES.The overall service supply increased more than the respective demand due to some reforestation of open land.As forests were found to be important synergistic areas for overall service provision,we expect decreasing demand on related services.Locally,demand was found to exceed the supply of ES,especially in the densely populated Rhine valley-requiring further policy interventions.Such ES-related information may contribute to regional policy making and ensure the long-term provision of ESs for future generations.
文摘Ionizing radiation caused by medical treatments,nuclear events or even space flights can irreversibly damage structure and function of brain cells.That can result in serious brain damage,with memory and behavior disorders,or even fatal oncologic or neurodegenerative illnesses.Currently used treatments and drugs are mostly targeting biochemical processes of cell apoptosis,radiation toxicity,neuroinflammation,and conditions such as cognitive-behavioral disturbances or others that result from the radiation insult.With most drugs,the side effects and potential toxicity are also to be considered.Therefore,many agents have not been approved for clinical use yet.In this review,we focus on the latest and most effective agents that have been used in animal and also in the human research,and clinical treatments.They could have the potential therapeutical use in cases of radiation damage of central nervous system,and also in prevention considering their radioprotecting effect of nervous tissue.