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The majority of microplastic research has focused on seawater, with fewer than 4% of microplasticsrelated studies occurring on freshwaters. The limited available information suggests that the abundance of microplastics in freshwaters is often as high or even higher than marine environments. However, comprehensive investigations on occurrence and fate of microplastics in freshwaters are scarce and highly fragmented, partly because detection and identification of microplastic particles is rather complex. In addition, up to now, harmonized and standardized protocols for the sampling and analysis of microplastics in freshwaters do not exist, and studies with different research aims and hypotheses often report unstandardized results, making comparison among studies difficult. In the present study, we performed the first global standardized sampling and analysis effort to investigate the occurrence and distribution of microplastics in surface water of lakes and reservoirs with different anthropogenic impacts. Participants aim to collect water samples of freshwater systems with different features (e.g., area, depth, thermal behavior, watershed), following a common protocol. This 18 establishes the collection of samples by horizontal trawling of a plankton net and, after treatment with hydrogen peroxide, the polymer identification through micro-Raman spectroscopy. This GLEON project will allow obtaining comparable data about microplastic contamination in different freshwater systems around the globe. With this global dataset, our goals are to determine whether a relationship exists between the abundance of microplastics and the waterbody/watershed attributes and understand which factors are likely to influence the occurrence of microplastics in surface water of lentic systems. info:eu-repo/semantics/publishedVersion

Artificial intelligence-driven robots are increasingly being introduced in various workplaces. Research implies that people’s negative attitudes toward intelligent and collaborative robots might hinder their willingness to use them. We propose that interactive educational activities such as specialized workshops help people to overcome such negative attitudes. We designed a two-day workshop that introduced two quasi-industrial robots (Poppy Ergo Jr and ClearBot) to 16 university students. Students’ attitudes were qualitatively measured before and after the workshop. The results imply that the workshop helped students to increase their understanding of the nature of the intelligent collaborative robots. More precisely, robots became to be seen as empowering tools, rather than friends or enemies. Interestingly, there were significant gender differences, as the female participants had a greater tendency to view robots as animated objects. We concluded that specialized workshops effectively lead participants to become aware of various promising opportunities for their robotic co-workers in the possible future.

The denaturation of globular proteins by high pressure is frequently associated with the release of internal voids and/or the exposure of the hydrophobic protein interior to a polar aqueous solvent. Similar evidence with respect to membrane proteins is not available. Here, we investigate the impact of hydrostatic pressures reaching 12 kbar on light-harvesting 2 integral membrane complexes of purple photosynthetic bacteria using two types of innate chromophores in separate strategic locations: bacteriochlorophyll-a in the hydrophobic interior and tryptophan at both protein-solvent interfacial gateways to internal voids. The complexes from mutant Rhodobacter sphaeroides with low resilience against pressure were considered in parallel with the naturally robust complexes of Thermochromatium tepidum. In the former case, a firm correlation was established between the abrupt blue shift of the bacteriochlorophyll-a exciton absorption, a known indicator of the breakage of tertiary structure pigment-protein hydrogen bonds, and the quenching of tryptophan fluorescence, a supposed result of further protein solvation. No such effects were observed in the reference complex. While these data may be naively taken as supporting evidence of the governing role of hydration, the analysis of atomistic model structures of the complexes confirmed the critical part of the structure in the pressure-induced denaturation of the membrane proteins studied.

Flexible color adaptation to available ecological niches is vital for the photosynthetic organisms to thrive. Hence, most purple bacteria living in the shade of green plants and algae apply bacteriochlorophyll a pigments to harvest near infra-red light around 850–875 nm. Exceptions are some Ca2+-containing species fit to utilize much redder quanta. The physical basis of such anomalous absorbance shift equivalent to ~5.5 kT at ambient temperature remains unsettled so far. Here, by applying several sophisticated spectroscopic techniques, we show that the Ca2+ ions bound to the structure of LH1 core light-harvesting pigment–protein complex significantly increase the couplings between the bacteriochlorophyll pigments. We thus establish the Ca-facilitated enhancement of exciton couplings as the main mechanism of the record spectral red-shift. The changes in specific interactions such as pigment–protein hydrogen bonding, although present, turned out to be secondary in this regard. Apart from solving the two-decade-old conundrum, these results complement the list of physical principles applicable for efficient spectral tuning of photo-sensitive molecular nano-systems, native or synthetic.

Predawn water potential disequilibrium in hybrid aspen coppice growing in humid environment was mostly determined by hydraulic conductance and the ratio of nocturnal to daily water loss was relatively small. Water relations are of crucial importance for biomass accumulation in trees and forest productivity, yet the significance of nocturnal water use is still debated. We investigated which environmental factors influence nocturnal transpiration, development of the equilibrium between soil and plant water potentials and plant hydraulic conductance in hybrid aspen (Populus tremula L. × P. tremuloides Michx.) coppice. Predawn leaf water potential and sap flow were measured simultaneously with relevant environmental factors on 2-year-old coppice shoots during the growing season of 2015. Nocturnal water loss constituted on average 4–5% of daily total transpiration and almost 2/3 of nocturnal sap flow. The nocturnal water loss was mainly driven by atmospheric evaporative demand, while maximum sap flux densities could extend 35% of the daytime values on dry nights. Predawn leaf water potential was constantly more negative than soil water potential, resulting in predawn disequlibrium between leaf and soil water potentials (PDD). Total soil-to-leaf hydraulic conductance was the primary factor explaining the variation in PDD. Our results suggest that in humid conditions plant hydraulic capacity is more substantial determining plant predawn water status than stomatal behaviour with respect to current environmental drivers.

With the rapid development in data acquisition and presentation, there is a growing interest in virtual forests and computer visualization tools. Forest owners have become more aware about their property and are interested in applying different forest management methods and silvicultural techniques. The tools are also applicable in assessment of the changes to the landscape as a result of natural and anthropogenic disturbances. Virtual reality offers a good opportunity to test and compare different management options before implementing decisions which can lead to irreversible consequences. Advances in spatial and temporal data collection enable new and practical solutions for analysis and visualization of long-term natural processes with new forestry applications. In the near future, forest owners and managers will have the possibility to make management decisions without the direct need to exit the office. Furthermore, the learning process is more enthralling and also more profound through augmented reality, helping to foster better working practices even before starting a job in the forest sector.

We used elastic incoherent neutron scattering (EINS) to find out if structural changes accompanying local hydrogen bond rupture are also reflected in global dynamical response of the protein complex. Chromatophore membranes from LH2-only strains of the photosynthetic bacterium Rhodobacter sphaeroides, with spheroidenone or neurosporene as the major carotenoids, were subjected to high hydrostatic pressure at ambient temperature. Optical spectroscopy conducted at high pressure confirmed rupture of tertiary structure hydrogen bonds. In parallel, we used EINS to follow average motions of the hydrogen atoms in LH2, which reflect the flexibility of this complex. A decrease of the average atomic mean square displacements of hydrogen atoms was observed up to a pressure of 5 kbar in both carotenoid samples due to general stiffening of protein structures, while at higher pressures a slight increase of the displacements was detected in the neurosporene mutant LH2 sample only. These data show a correlation between the local pressure-induced breakage of H-bonds, observed in optical spectra, with the altered protein dynamics monitored by EINS. The slightly higher compressibility of the neurosporene mutant sample shows that even subtle alterations of carotenoids are manifested on a larger scale and emphasize a close connection between the local structure and global dynamics of this membrane protein complex.

Diverse structural elements play an important role in sustaining biodiversity in old-growth forests. Therefore, it is important to have thorough knowledge about these habitats and their condition in protected areas. Metsakorralduse Büroo OÜ conducted a large-scale Natura 2000 forest habitat inventory that covered 60% of Lahemaa National Park (LNP) area. Western taiga habitat data (7,191 ha) from this inventory was used for analysis of forest stages. The data was grouped according to stand classes by total area and these classes were compared by deadwood occurrence and relative density. For more precise evaluation of coarse woody debris (CWD) we used 27 sample plots from the Estonian Network of Forest Research Plots (ENFRP) located in LNP. The biggest areas of Western taiga habitat were covered by mature and old stages. CWD occurrence (over 5 m3ha−1 of snags and logs) by habitat representativeness is higher in old and natural forest classes. This logical result is overshadowed by the outcome that the CWD was not substantially present on 32% of the area in the old-growth forest class. This indicates that these areas lack the potential of biological legacies to provide critical niche habitats for different species. The study shows that the CWD quantity in Estonian conditions is similar to that reported in previous studies in this region, but because many of the older forest stage classes do not have any CWD present, these areas should include ecological restoration practices in their conservation planning. By creating snags, logs and gaps in these areas, we are able to create better structural variability and include wood into different decay processes.

In the current study we show that the combustion of sol-gel derived alcogels with specifically tailored composition leads to the release of silica nanoparticles from the burning alcogel in a controlled manner which enables direct deposition of the released nanoparticles into low-density silica thick films. The process has some similarities to flame spray pyrolysis but requires no aerosol generator or other sophisticated instrumental setup. By the proper choice of catalysts and mixture of silicon alkoxides for the synthesis of the alcogel, preferential hydrolysis and polycondensation of one of the alkoxides is achieved. This leads to the formation of an alcogel with volatile silica precursor trapped in the gel pores. Resulting alcogels were burned to deposit uniform porous silica films with density of ~0.1 g/cm3 and primary particle size of ~10 nm. Demonstrated method yields silanol-free silica directly, without additional treatment steps and enables straightforward control over the deposition rate and coarseness of the layer by simple adjustment of the composition of the silica alcogel. The maximum layer thickness is limited only by the deposition time (in the current work up to 134 μm). Such technique of porous oxide film preparation could potentially be extended to the preparation of porous films from other oxides by using respective metal alkoxides as precursors., Porous silica; Low density; Silanol-free; Sol-gel; Combustion synthesis.

The Greek pension system has been costly, complex, and distortive, which has contributed to Greece’s fiscal problems and discouraged labor force participation. Several attempts to reform the system faltered due to lack of implementation, pushback by vested interests, and court rulings leading to reversals. A series of reforms introduced throughout 2015–17 unified benefit and contribution rules, removed several distortions and reduced fragmentation and costs. If fully implemented throughout the long-term, these reforms can go a long way towards enhancing the pension system affordability. However, reforms faced setbacks and fell short of creating stronger incentives to build long contribution histories, to deliver sustainable growth by improving the fiscal policy mix, and to ensure fairness and equitable burden sharing across generations and interest groups. Policy priorities should aim towards fully implementing the 2015–17 reforms and complementing them with additional reforms to address these remaining objectives.

During the past decade or so empirical literature on comparative development of nations has turned to investigation of "deep" or determinants of productivity and capital intensity, such as institutions, trade, geography and human capital. In this paper I revisit this debate and make three contributions. First, I review critically the main findings in the literature using all potentially endogenous determinants of comparative development. The findings suggest that in general the results are not robust to the use of measures of institutional quality and/or respective instruments, and might be misspecified. Second, I make a careful selection across all the instruments for all the deep determinants and argue that settler mortality proposed by Acemoglu et al. (2001) is not a dominant instrument for institutional quality and its potentially the most prone to fail to satisfy the exclusion restriction. Consequently I provide evidence that the theory of colonial origins is not institutional in its nature and rather supports human capital prevalence hypothesis. Third, I show that earlier studies have failed to account for substitutable roles between institutions and openness. In the final race, however, human capital and geography come out as winners with openness having at best indirect complementary effects.

In this study, GNF@ZnO composites (gelatin nanofibers (GNF) with zinc oxide (ZnO) nanoparticles (NPs)) as a novel antibacterial agent were obtained using a wet chemistry approach. The physicochemical characterization of ZnO nanoparticles (NPs) and GNF@ZnO composites, as well as the evaluation of their antibacterial activity toward Gram-positive (Staphyloccocus aureus and Bacillus pumilus) and Gram-negative (Escherichia coli and Pseudomonas fluorescens) bacteria were performed. ZnO NPs were synthesized using a facile sol-gel approach. Gelatin nanofibers (GNF) were obtained by an electrospinning technique. GNF@ZnO composites were obtained by adding previously produced GNF into a Zn2+ methanol solution during ZnO NPs synthesis. Crystal structure, phase, and elemental compositions, morphology, as well as photoluminescent properties of pristine ZnO NPs, pristine GNF, and GNF@ZnO composites were characterized using powder X-ray diffraction (XRD), FTIR analysis, transmission and scanning electron microscopies (TEM/SEM), and photoluminescence spectroscopy. SEM, EDX, as well as FTIR analyses, confirmed the adsorption of ZnO NPs on the GNF surface. The pristine ZnO NPs were highly crystalline and monodispersed with a size of approximately 7 nm and had a high surface area (83 m2/g). The thickness of the pristine gelatin nanofiber was around 1 &micro, m. The antibacterial properties of GNF@ZnO composites were investigated by a disk diffusion assay on agar plates. Results show that both pristine ZnO NPs and their GNF-based composites have the strongest antibacterial properties against Pseudomonas fluorescence and Staphylococcus aureus, with the zone of inhibition above 10 mm. Right behind them is Escherichia coli with slightly less inhibition of bacterial growth. These properties of GNF@ZnO composites suggest their suitability for a range of antimicrobial uses, such as in the food industry or in biomedical applications.

Väitekirja elektrooniline versioon ei sisalda publikatsioone, Tavapäraselt uuritakse taimi päevasel ajal, kui toimub fotosüntees ning intensiivne veevahetus taime ja keskkonna vahel. Kuid paaril viimasel kümnendil on uurijate hulgas olulist tähelepanu pälvinud ka öine ja eriti koidueelne taimede veevahetus. Senini ei ole selgelt teada, millised faktorid ja kuidas mõjutavad öist ksüleemivoolu ehk vee liikumist vartes, lehtedel asuvate õhulõhede avatust öösel ja enne koitu ning lehe koidueelset veepotentsiaali, mida sageli kasutatakse mulla veestaatuse hinnanguna. Kasvuhoones üheksa parasvöötme puuliigi peal läbi viidud katse näitas, et mulla piisava veevarustuse korral on kiiremakasvuliste pioneerliikide öine õhulõhede juhtivus kõrgem kui aeglasekasvulistel liikidel. See reegel kehtib liikide puhul, mis asustavad parasvöötme niiskemaid ja jahedamaid piirkondi: harilik haab (Populus tremula), arukask (Betula pendula) ja sanglepp (Alnus glutinosa). Põuatingimustes liikide vahel erinevused õhulõhede juhtivuses kaovad. Eestis läbi viidud eksperimendi käigus kogutud andmed demonstreerisid hübriidhaaval (Populus tremula × P. tremuloides) erinevust lehe ja mulla veepotentsiaalide vahel ja öise ksüleemivoolu esinemist. Mõlema tunnuse positiivne sõltuvus atmosfääri kuivusest viitab selgelt asjaolule, et sel liigil on õhulõhed öösel avatud. Sellest tulemusest järeldub, et kuivemate ja soojemate ööde korral ei saa koidueelset lehe veepotentsiaali kasutada mulla veestaatuse hinnanguna. Lisaks tõestasid meie eksperimendid, et hübriidhaab on võimeline omastama kastevett lehtede pinnalt, mis võib koidueelset veepotentsiaali omakorda vastupidiselt mõjutada. Kasvukambris läbi viidud katses näitasid kõrge päevase õhuniiskuse tingimustes kasvanud hübriidhaavad, et nende öine ksüleemivool suureneb, kui järsult õhuniiskust vähendada. Mõõduka õhuniiskuse käes kasvanud puudel sellist reaktsiooni ei täheldatud. See viitab kõrgema õhuniiskusega keskkonnas kasvanud puude nõrgenenud õhulõhede kontrollile. Välikatsetes sellist efekti ei tuvastatud. Võttes arvesse nii regionaalseid kui globaalseid kliimamuutuste trende, on väga tõenäoline, et suureneb nii puude öise transpiratsiooni osakaal kogu ööpäevases veekaos kui ka vajadus arvestada öise transpiratsiooniga ökosüsteemide veebilansi arvutustes., Plants are usually studied during daytime when photosynthesis and intensive water exchange between the plant and the environment takes place. However, nocturnal and predawn water relations of plants have also gained considerable attention during recent decades. Nevertheless, there are still uncertainties what factors and how may affect characteristics like nocturnal sap flow, nocturnal and predawn stomatal conductance, and predawn leaf water potential – a characteristic commonly used for estimating soil water status. The aim of this thesis was to compare nocturnal stomatal conductance and predawn water potential disequilibrium between leaf and soil (PDD) in temperate deciduous tree species differing in ecological demands and life strategies; to elucidate the environmental factors that govern nocturnal transpiration and PDD; and to test whether increasing daytime atmospheric humidity – a climate trend predicted for high northern latitudes – affects nocturnal water use in broadleaved trees. An experiment in nine temperate tree species in a greenhouse demonstrated that under ample soil water availability, fast-growing pioneer species exhibited higher night-time stomatal conductance compared to slow-growing late-successional species. That was true about the species originating from more humid and cooler regions (e.g. Populus tremula, Betula pendula, Alnus glutinosa). In drought conditions the differences in stomatal conductance between the species disappeared. Field studies carried out in Estonia proved the occurrence of significant PDD and nocturnal sap flow in hybrid aspen (Populus tremula × P. tremuloides). Positive effect of nocturnal atmospheric evaporative demand on both characteristics is a solid proof of open stomata at night. This suggests that under drier and warmer atmospheric conditions predawn leaf water status cannot be used as a reliable estimate of soil water status. Our experiments proved that hybrid aspen trees are able to absorb dew water from leaf surface, exhibiting foliar water uptake, which might also bias predawn leaf water status. In a growth chamber experiment, hybrid aspen saplings grown under elevated air humidity responded with increased sap flux density to a rise in atmospheric evaporative demand at night, which evidences weakened stomatal control over water loss, although the field studies did not support that finding. Taking into account the regional and global climate trends, it is very likely that the proportion of nocturnal water losses in total daily transpiration of trees as well as the necessity for considering nocturnal transpiration in calculations of landscape or ecosystem water balance will increase in the future., https://www.ester.ee/record=b5360588

Bakalaureusetöö Loomakasvatuse õppekaval Eestis on mahetootmine viimasel ajal kiiresti arenenud ja mahemaa osakaal kogu põllumajanduslikust maast moodustab juba üle 21%. Sarnast kasvu ei ole aga toimunud mahepiima tootmisel ja viimasel viiel aastal on mahelehmade arv Eestis püsima jäänud. Antud bakalaureusetöö eesmärgiks oli analüüsida mahelehmade tootmisnäitajaid aastatel 2017-2019. Töö alaeesmärgid olid: 1) Analüüsida mahelehmade järgnevaid jõudlusnäitajaid: toodangunäitajad, piima somaatiliste rakkude arv ja -karbamiidi sisaldus ning eluea toodangu näitajad 2) Selgitada välja mahelehmade karjast väljamineku peamised põhjused. Mahepiimatootjate üldandmed saadi Põllumajandusametist. Analüüsiti vaid jõudluskontrollis osalevate tootjate karju, mille tulemusena jäi valimisse 18 tootjat. Andmete analüüsimiseks kasutati programmi MS Excel. Keskmine 305 päeva piimatoodang Eesti mahekarjades aastatel 2017-2019 oli 5828 kg. Aastate lõikes oli 305 päeva keskmine piimatoodang mahekarjades teinud alates 2018. aastast ligikaudu 320 kg suuruse tõusu 5982 kg-ni 2019. aastal. Eesti mahefarmidest kogutud kontroll-lüpside analüüsimise tulemusena saadi 2017-2019 aastal keskmiseks ööpäevaseks piimatoodanguks 18,8 kg. Keskmine piima rasvasisaldus mahekarjades antud perioodil oli 4,40% ja valgusisaldus 3,41%. Analüüsist selgus, et keskmine somaatiliste rakkude arv piima milliliitri kohta oli mahekarjades 506 tuhat. Aastatel 2017-2019 mahekarjadest kogutud keskmine karbamiidi kogus piimas oli 222mg/l . Uuritud mahelehmade peamise karjast väljamineku põhjusena toodi välja sigimisprobleemid. Keskmine mahepiimalehmade eluea piimatoodang oli aastatel 2017.- 2019. 20 367 kg In Estonia, organic production has recently developed rapidly and the share of organic land in the total agricultural area is already more than 21%. However, no similar growth has taken place in the production of organic milk and the number of organic cows has remained stable in Estonia during the last five years. The aim of this bachelor thesis was to analyze the production indicators of organic cows between 2017-2019. The main research topics were: 1) Analyze the following production traits of organic cows: indicators of milk production, somatic cell count (SCC), urea content and life time production indicators 2) Identify the main reasons for culling organic cows The general data about organic producers was obtained from the Agricultural Board Office. Only producers participating in the animal performance recording were analyzed, resulting in 18 producers remaining in the selection. MS Excel was used to analyze the data. The average 305 days milk yield in Estonian organic herds between 2017-2019 was 5828 kg. Over the years, the 305 days average milk yield in organic herds has increased approximately 320 kg from year 2018 to 5982 kg in 2019. As a result of the control milking, 18,8 kg of average daily milk production was obtained from Estonian organic farms in years 2017-2019. The average fat content in milk during the given period was 4,40% and the protein content in milk was 3,41%. The analysis revealed that the average somatic cell count per milliliter of organic milk was 506 000 . The average amount of urea content in milk collected from organic herds was 222mg/l . Fertility problems were identified as the main reason for culling of organic cows. The average life time milk production of organic dairy cows in years 2017-2019 was 20 367 kg.

Lake eutrophication is a pervasive problem globally, particularly serious in agricultural and densely populated areas. Whenever nutrients nitrogen and phosphorus do not limit phytoplankton growth directly, high growth rates will rapidly lead to biomass increases causing self-shading and light-limitation, and eventually CO

Globally, our knowledge on lake fisheries is still limited despite their importance to food security and livelihoods. Here we show that fish catches can respond either positively or negatively to climate and land-use changes, by analyzing time-series data (1970–2014) for 31 lakes across five continents. We find that effects of a climate or land-use driver (e.g., air temperature) on lake environment could be relatively consistent in directions, but consequential changes in a lake-environmental factor (e.g., water temperature) could result in either increases or decreases in fish catch in a given lake. A subsequent correlation analysis indicates that reductions in fish catch was less likely to occur in response to potential climate and land-use changes if a lake is located in a region with greater access to clean water. This finding suggests that adequate investments for water-quality protection and water-use efficiency can provide additional benefits to lake fisheries and food security., Lake fisheries are vulnerable to environmental changes. Here, Kao et al. develop a Bayesian networks model to analyze time-series data from 31 major fisheries lake across five continents, showing that fish catches can respond either positively or negatively to climate and land-use changes.

The data paper refers to the research article “Assessment of spatial stand structure of hemiboreal conifer dominated forests according to different levels of naturalness” [1]. Forest ecosystem structure was quantified by using structural indices based on the nearest-neighborhood approach for individual trees. Species mingling, deadwood mingling, deadwood distribution, diameter differentiation and the uniform angle indices characterize the patterns of the complexity and diversity of forest ecosystems, including the arrangement of tree dimensions, species and deadwood as well as tree positioning regularities. The data is collected all over Estonia from the Estonian Network of Forest Research Plots; altogether 212 sample plots were used in this study. The plots of the Estonian Network of Forest Research Plots are re-measured in nature with an interval of five years. Forests were classified by their naturalness level as managed forests, recovering forests and natural forests. The information in this paper can be used by forest inventories for developing the methods of ecosystem naturalness assessment as well as for analysing naturalness, stand structures and tree patterns in hemiboreal forest ecosystems. Keywords: Forest assessment, Species mingling, Deadwood, Diameter differentiation, Tree positioning patterns, Scots pine, Norway spruce