This work presents new calculations of conversion coefficients (CCs) from total air kerma to dose-equivalent quantitiesH'(0.07),H'(3),H*(10),Hp(0.07),Hp(3), andHp(10) for area and personal dosimetry for mono-energetic photons in the energy range from 2 keV to 50 MeV, assuming secondary charged particle equilibrium. Calculations using the Monte Carlo N-Particle® (MCNP) code were performed for a large number of photon energies with the aim of preventing errors resulting from possible improper interpolation between currently available sparsely spaced CC values, when an average CC value over a photon fluence spectrum needs to be determined. The CC values were compared with the values published in the ISO 4037-3:2019 standard. A very close agreement was achieved for the majority of CCs. Larger discrepancies were found for some CCs, often for low photon energies or large angles of radiation incidence, which were taken from older publications or when CC values were interpolated or extrapolated. Furthermore, some differences were found in the MeV energy range, which are significant for dosimeter calibrations, e.g. the presented values of CC toH*(10) for the main photon energies of137Cs and60Co radionuclides are both lower by 2.8%. Finally, it was found that the values of CCs toHp(0.07;E, α)slabgiven in ISO 4037-3:2019 were not taken correctly from the source publication. In conclusion, the CC values given in ISO 4037-3:2019 should be updated in view of the results obtained.

• Klíčová slova
• ISO 4037 standard, MCNP, Monte Carlo, area dosimetry, conversion coefficients, personal dosimetry, total air kerma,
• MeSH
• dávka záření * MeSH
• fotony * MeSH
• lidé MeSH
• metoda Monte Carlo MeSH
• radiometrie * metody   MeSH
• vzduch MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

The jet stream is an important dynamic driver of climate variability in the Northern Hemisphere mid-latitudes1-3. Modern variability in the position of summer jet stream latitude in the North Atlantic-European sector (EU JSL) promotes dipole patterns in air pressure, temperature, precipitation and drought between northwestern and southeastern Europe. EU JSL variability and its impacts on regional climatic extremes and societal events are poorly understood, particularly before anthropogenic warming. Based on three temperature-sensitive European tree-ring records, we develop a reconstruction of interannual summer EU JSL variability over the period 1300-2004 CE (R2 = 38.5%) and compare it to independent historical documented climatic and societal records, such as grape harvest, grain prices, plagues and human mortality. Here we show contrasting summer climate extremes associated with EU JSL variability back to 1300 CE as well as biophysical, economic and human demographic impacts, including wildfires and epidemics. In light of projections for altered jet stream behaviour and intensified climate extremes, our findings underscore the importance of considering EU JSL variability when evaluating amplified future climate risk.

• MeSH
• atmosférický tlak MeSH
• dějiny 15. století MeSH
• dějiny 16. století MeSH
• dějiny 17. století MeSH
• dějiny 18. století MeSH
• dějiny 19. století MeSH
• dějiny 20. století MeSH
• dějiny 21. století MeSH
• dějiny středověku MeSH
• déšť MeSH
• epidemie dějiny   statistika a číselné údaje   MeSH
• jedlá semena ekonomika   dějiny   zásobování a distribuce   MeSH
• klimatické změny statistika a číselné údaje   MeSH
• lidé MeSH
• mortalita dějiny   MeSH
• nadmořská výška * MeSH
• období sucha dějiny   statistika a číselné údaje   MeSH
• pěstování plodin * dějiny   statistika a číselné údaje   MeSH
• podnebí * MeSH
• požáry v divočině dějiny   statistika a číselné údaje   MeSH
• roční období MeSH
• stromy růst a vývoj   MeSH
• teplota MeSH
• Vitis MeSH
• vítr * MeSH
• Check Tag
• dějiny 15. století MeSH
• dějiny 16. století MeSH
• dějiny 17. století MeSH
• dějiny 18. století MeSH
• dějiny 19. století MeSH
• dějiny 20. století MeSH
• dějiny 21. století MeSH
• dějiny středověku MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• historické články MeSH
• Geografické názvy
• Evropa MeSH

Offshore wind energy developments in European waters are rapidly expanding to meet the increasing global demand for renewable energy. These developments provide new substrates for species colonisation, but also introduce changes in electromagnetic fields, noise levels, and hydrological conditions. Understanding how these man-made structures affect marine biodiversity across various species groups is crucial, yet our knowledge in this field remains incomplete. In this synthesis paper, based on 14 case studies conducted in northeastern Atlantic (North, Irish and Baltic seas), we aggregated species-level data on abundance, biomass, and other quantity proxies spanning the entire food chain from invertebrates to mammals, and compared these variables between wind farms and nearby control sites. Overall, our analysis revealed that in wind farm areas, species tend to occur at higher quantities than in control areas. Additionally, we noticed a slight trend where the positive effect of wind farms was more pronounced in newly established ones, gradually diminishing as wind farms aged. None of the tested covariates (depth, distance from coastline, years in commission) nor species' characteristics (habitat and spawning types, trophic level) showed statistical significance. When examining species groups individually, there was a tendency for wind farm areas to harbour higher quantities of polychaetes, echinoderms and demersal fishes. These findings suggest that wind farms contribute to the so-called reef-effect, providing shelter and food supplies to their inhabitants and acting as no-take-zones. Our results support the idea that wind farms could serve as zones of increased local biodiversity, potentially facilitating spillover effects to nearby areas for certain species groups. Further studies are necessary to gain a more comprehensive understanding of the adverse effects of wind farms on associated biodiversity, while also exploring avenues to amplify their positive impacts.

• Klíčová slova
• Abundance, Anthropogenic disturbance, Biomass, Fish, Marine ecosystems, Wind parks,
• MeSH
• biodiverzita * MeSH
• ekosystém MeSH
• monitorování životního prostředí MeSH
• obnovitelná energie MeSH
• vítr * MeSH
• vodní organismy MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• systematický přehled MeSH

Nanobubble water promotes the degradation of difficult-to-degrade organic matter, improves the activity of electron transfer systems during anaerobic digestion, and optimizes the composition of anaerobic microbial communities. Therefore, this study proposes the use of nanobubble water to improve the yield of medium chain carboxylic acids produced from cow manure by chain elongation. The experiment was divided into two stages: the first stage involved the acidification of cow manure to produce volatile acidic fatty acids as electron acceptors, and the second phase involved the addition of lactic acid as an electron donor for the chain elongation. Three experimental groups were established, and air, H2, and N2 nanobubble water were added in the second stage. Equal amounts of deionized water were added in the control group. The results showed that nanobubble water supplemented with air significantly increased the caproic acid concentration to 15.10 g/L, which was 55.03 % greater than that of the control group. The relative abundances of Bacillus and Caproiciproducens, which are involved in chain elongation, and Syntrophomonas, which is involved in electron transfer, increased. The unique ability of air nanobubble water supplemented to break down the cellulose matrix resulted in further decomposition of the recalcitrant material in cow manure. This effect subsequently increased the number of microorganisms associated with lignocellulose degradation, increasing carbohydrate metabolism and ATP-binding cassette transporter protein activity and enhancing fatty acid cycling pathways during chain elongation. Ultimately, this approach enabled the efficient production of medium chain carboxylic acids.

• Klíčová slova
• Anaerobic digestion, Chain elongation, Electron transport, Fatty acid cycle pathway, Nanobubble water,
• MeSH
• anaerobióza MeSH
• biodegradace * MeSH
• Clostridiales MeSH
• dusík chemie   MeSH
• hnůj * MeSH
• kyseliny karboxylové chemie   MeSH
• kyseliny mastné těkavé chemie   MeSH
• nanostruktury MeSH
• skot MeSH
• transport elektronů MeSH
• voda chemie   MeSH
• vodík chemie   MeSH
• vzduch MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• dusík MeSH
• hnůj * MeSH
• kyseliny karboxylové MeSH
• kyseliny mastné těkavé MeSH
• lignocellulose MeSH Prohlížeč
• voda MeSH
• vodík MeSH

Various mechanical, hydraulic, pneumatic, electrical, and hybrid actuators can alter motion per the requirements of particular applications. However, except for electrical ones, all actuators are restricted due to their size, complex auxiliary equipment, frequent need for maintenance, and sluggish environment in renewable applications. This brief review paper highlights some unique and significant research works on applying electrical actuators to renewable applications. Four renewable energy resources, i.e., solar, wind, bio-energy, and geothermal energy, are considered to review electric actuators applicable to renewable energy systems. This review analyses the types of actuators associated with the mentioned renewable application, their functioning, their motion type, present use, advantages, disadvantages, and operational problems. The information gathered in this paper may open up new ways of optimization opportunities and control challenges in electrical actuators, thereby making more efficient systems. Furthermore, some energy-efficient and cost-effective replacements of convectional actuators with new innovative ones are suggested. This work aims to benefit scientists and new entrants working on actuators in renewable energy systems.

• Klíčová slova
• electric actuators, linear actuators, power consumption, renewable system, rotary actuators, spherical actuators,
• MeSH
• elektřina * MeSH
• obnovitelná energie * MeSH
• vítr MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

The mechanistic pathways connecting ocean-atmosphere variability and terrestrial productivity are well-established theoretically, but remain challenging to quantify empirically. Such quantification will greatly improve the assessment and prediction of changes in terrestrial carbon sequestration in response to dynamically induced climatic extremes. The jet stream latitude (JSL) over the North Atlantic-European domain provides a synthetic and robust physical framework that integrates climate variability not accounted for by atmospheric circulation patterns alone. Surface climate impacts of north-south summer JSL displacements are not uniform across Europe, but rather create a northwestern-southeastern dipole in forest productivity and radial-growth anomalies. Summer JSL variability over the eastern North Atlantic-European domain (5-40E) exerts the strongest impact on European beech, inducing anomalies of up to 30% in modelled gross primary productivity and 50% in radial tree growth. The net effects of JSL movements on terrestrial carbon fluxes depend on forest density, carbon stocks, and productivity imbalances across biogeographic regions.

• MeSH
• buk (rod) * MeSH
• klimatické změny MeSH
• lesy MeSH
• pohyb vzduchu MeSH
• uhlík MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Názvy látek
• uhlík MeSH

RATIONALE: The reactions of the reagent ions used for trace gas analysis in selected ion flow tube mass spectrometry (SIFT-MS), R+ , viz. H3 O+ , NO+ and O2 + , with the major gases in air and breath samples, M, viz. N2 , O2 , CO2 and H2 O, are investigated. These reactions are seen to form weakly-bound adduct ions, R+ M, by ternary association reactions that must not be mistaken for genuine volatile organic compound (VOC) analyte ions. METHODS: The ternary association rate coefficients mediated by helium (He) carrier gas atoms, k3a , have been determined for all combinations of R+ and M, which form R+ M adduct ions ranging in m/z from 47 (H3 O+ N2 ) to 76 (O2 +• CO2 ). This was achieved by adding variable amounts of M (up to 0.5 mbar pressure) into the He carrier gas (pressure of 1.33 mbar) in a SIFT-MS flow tube at 300 K. Parabolic curvature was observed on some of the semi-logarithmic decay curves that allowed the rate coefficients mediated by M molecules, k3b , to be estimated. RESULTS: Values of k3a were found to range from 1 × 10-31 cm6 s-1 to 5 × 10-29 cm6 s-1 , which form mass spectral R+ M "ghost peaks" of significant strength when analysing VOCs at parts-per-billion concentrations. It was seen that the R+ M adduct ions (except when M is H2 O) react with H2 O molecules by ligand switching forming the readily recognised monohydrates of the initial reagent cations R+ H2 O. Whilst this ligand switching diminishes the R+ M adduct ghost peaks, it does not eliminate them entirely. CONCLUSIONS: The significance of these adduct ions for trace gas analysis by SIFT-MS in the low m/z region is alluded to, and some examples are given of m/z spectral overlaps of the R+ M and R+ H2 O adduct cations with analyte cations of VOCs formed by analysis of complex media like exhaled breath, warning that ghost peaks will be enhanced using nitrogen carrier gas in SIFT-MS.

• MeSH
• dechové testy MeSH
• hmotnostní spektrometrie MeSH
• ionty chemie   MeSH
• kyslík chemie   MeSH
• lidé MeSH
• oxid dusnatý chemie   MeSH
• oxid uhličitý chemie   MeSH
• reaktivní formy kyslíku chemie   MeSH
• těkavé organické sloučeniny chemie   MeSH
• voda chemie   MeSH
• vzduch analýza   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ionty MeSH
• kyslík MeSH
• oxid dusnatý MeSH
• oxid uhličitý MeSH
• reaktivní formy kyslíku MeSH
• těkavé organické sloučeniny MeSH
• voda MeSH

Present-day disturbances are transforming European forest landscapes, and their legacies determine the vulnerability and resilience of the emergent forest generation. To understand these legacy effects, we investigated the resilience of the aboveground forest biomass (Babg) to a sequence of disturbances affecting the forest in different recovery phases from the initial large-scale impact. We used the model iLand to simulate windthrows that affected 13-24% of the Babg in a Central European forest landscape. An additional wind event was simulated 20, 40, 60, or 80 years after the initial impact (i.e., sequences of two windthrows were defined). Each windthrow triggered an outbreak of bark beetles that interacted with the recovery processes. We evaluated the resistance of the Babg to and recovery after the impact. Random Forest models were used to identify factors influencing resilience. We found that Babg resistance was the lowest 20 years after the initial impact when the increased proportion of emergent wind-exposed forest edges prevailed the disturbance-dampening effect of reduced biomass levels and increased landscape heterogeneity. This forest had a remarkably high recovery rate and reached the pre-disturbance Babg within 28 years. The forest exhibited a higher resistance and a slower recovery rate in the more advanced recovery phases, reaching the pre-disturbance Babg within 60-80 years. The recovery was enhanced by higher levels of alpha and beta diversity. Under elevated air temperature, the bark beetle outbreak triggered by windthrow delayed the recovery. However, the positive effect of increased temperature on forest productivity caused the recovery rate to be higher under the warming scenario than under the reference climate. We conclude that resilience is not a static property, but its magnitude and drivers vary in time, depending on vegetation feedbacks, interactions between disturbances, and climate. Understanding these mechanisms is an essential step towards the operationalization of resilience-oriented stewardship.

• Klíčová slova
• Central Europe, Climate change, Compound disturbance impacts, Engineering resilience, Forest aboveground biomass,
• MeSH
• biomasa MeSH
• brouci * růst a vývoj   MeSH
• klimatické změny * MeSH
• lesy * MeSH
• vítr MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Evropa MeSH

In this paper, we describe the possibility of using the energy of a compressed air flow, where cryogenic temperatures are achieved within the flow behind the nozzle, when reaching a critical flow in order to maximize the energy gained. Compared to the energy of compressed air, the energy obtained thermoelectrically is negligible, but not zero. We are therefore primarily aiming to maximize the use of available energy sources. Behind the aperture separating regions with a pressure difference of several atmospheres, a supersonic flow with a large temperature drop develops. Based on the Seebeck effect, a thermocouple is placed in these low temperatures to create a thermoelectric voltage. This paper contains a mathematical-physical analysis for proper nozzle design, controlled gas expansion and ideal placement of a thermocouple within the flow for best utilization of the low temperature before a shockwave formation. If the gas flow passes through a perpendicular shockwave, the velocity drops sharply and the gas pressure rises, thereby increasing the temperature. In contrast, with a conical shockwave, such dramatic changes do not occur and the cooling effect is not impaired. This article also contains analyses for proper forming of the head shape of the thermocouple to avoid the formation of a detached shockwave, which causes temperature stagnation resulting in lower thermocouple cooling efficiency.

• Klíčová slova
• Laval nozzle, Peltier–Seebeck effect, conical shockwave, energy harvesting, harvester thermocouple, perpendicular/detached shockwave,
• MeSH
• atmosféra MeSH
• nízká teplota MeSH
• stlačený vzduch * MeSH
• teplota MeSH
• tlak MeSH
• Publikační typ
• časopisecké články MeSH

Air temperature has been the most commonly used exposure metric in assessing relationships between thermal stress and mortality. Lack of the high-quality meteorological station data necessary to adequately characterize the thermal environment has been one of the main limitations for the use of more complex thermal indices. Global climate reanalyses may provide an ideal platform to overcome this limitation and define complex heat and cold stress conditions anywhere in the world. In this study, we explored the potential of the Universal Thermal Climate Index (UTCI) based on ERA5 - the latest global climate reanalysis from the European Centre for Medium-Range Weather Forecasts (ECMWF) - as a health-related tool. Employing a novel ERA5-based thermal comfort dataset ERA5-HEAT, we investigated the relationships between the UTCI and daily mortality data in 21 cities across 9 European countries. We used distributed lag nonlinear models to assess exposure-response relationships between mortality and thermal conditions in individual cities. We then employed meta-regression models to pool the results for each city into four groups according to climate zone. To evaluate the performance of ERA5-based UTCI, we compared its effects on mortality with those for the station-based UTCI data. In order to assess the additional effect of the UTCI, the performance of ERA5-and station-based air temperature (T) was evaluated. Whilst generally similar heat- and cold-effects were observed for the ERA5-and station-based data in most locations, the important role of wind in the UTCI appeared in the results. The largest difference between any two datasets was found in the Southern European group of cities, where the relative risk of mortality at the 1st percentile of daily mean temperature distribution (1.29 and 1.30 according to the ERA5 vs station data, respectively) considerably exceeded the one for the daily mean UTCI (1.19 vs 1.22). These differences were mainly due to the effect of wind in the cold tail of the UTCI distribution. The comparison of exposure-response relationships between ERA5-and station-based data shows that ERA5-based UTCI may be a useful tool for definition of life-threatening thermal conditions in locations where high-quality station data are not available.

• Klíčová slova
• Cold, ERA5, ERA5-HEAT, Heat, Reanalysis, Thermal stress, UTCI,
• MeSH
• podnebí * MeSH
• velkoměsta MeSH
• vítr MeSH
• vysoká teplota * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa epidemiologie   MeSH
• velkoměsta MeSH