University of Latvia
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This chapter provides a tabular overview of the features exhibited by different CEE planning systems. A brief commentary is provided below the table for each country. We felt that presenting the material within ‘national’ tables, rather than, for example, ‘thematic’ tables, would make the text more readable for our audience. Specific issues requiring emphasis (and reference to other systems) are highlighted within the comments. The chapter provides a basic (synthesised and comparative) understanding of the key developments in national spatial planning systems. It is noteworthy that the solutions concerning each country are commented on in-depth, following the same pattern. This makes it possible to compare the different institutions. In characterising the spatial planning systems in the countries concerned, attention has been paid to various aspects. A key one seems to be the context concerning spatial planning at the local level and the related instruments. The context of spatial planning at regional and national levels has also been taken into account. Issues related to the role of the courts in spatial planning and environmental protection in spatial planning play a separate role.
The aim of the chapter is to compare approaches to the basic planning concepts and issues across CEE countries that are also member states of the European Union (EU). Based on their previous cooperation, the authors concluded that the following issues are important and worthwhile: Defining spatial planning and its objectives, Understanding spatial plans and their related concepts, Grasping the relationship between spatial planning and development policy, and the barriers that arise between them. Defining spatial planning allows for broader thematic comparisons. Spatial planning objectives, on the other hand, are the key reference point for the individual spatial planning instruments, both in terms of their creation and their evaluation. In addition to reflections resulting from observations of their own systems, the authors present reflections based on preliminary comparisons of solutions provided in CEE countries. Results stem from both ongoing analyses and previous joint research.
The chapter identifies key similarities and differences in the spatial planning systems studied. The results obtained are related to the previous discussion. Detailed spatial planning arrangements in the selected countries are then extracted. These solutions are presented in the form of case studies. The case studies were extracted using the following criteria: (1) the originality of the specific detailed solution, (2) the weakness/ineffectiveness of the specific detailed solution, and (3) the connection of the specific detailed solution with the sectoral sphere, in particular with the environmental sphere. The case studies were described according to similar schemes. The presentation of the case studies gives a broader view of the diverse possibilities in spatial planning systems. It also illustrates the possible consequences of such solutions and highlights related problems.
Soy leghemoglobin is one of the most important and key ingredients in plant-based meat substitutes that can imitate the colour and flavour of the meat. To improve the high-yield production of leghemoglobin protein and its main component—heme in the yeast Pichia pastoris, glycerol and methanol cultivation conditions were studied. Additionally, in-silico metabolic modelling analysis of growth-coupled enzyme quantity, suggests metabolic gene up/down-regulation strategies for heme production. First, cultivations and metabolic modelling analysis of P. pastoris were performed on glycerol and methanol in different growth media. Glycerol cultivation uptake and production rates can be increased by 50% according to metabolic modelling results, but methanol cultivation—is near the theoretical maximum. Growth-coupled metabolic optimisation results revealed the best feasible upregulation (33 reactions) (1.47% of total reactions) and 66 downregulation/deletion (2.98% of total) reaction suggestions. Finally, we describe reaction regulation suggestions with the highest potential to increase heme production yields.
Lead-free Ba1−xSrxTiO3 (BST) (x = 0, 0.1, 0.2, 0.3, 0.4 and 0.45) ceramics were successfully prepared via the solid-state reaction route. A pure perovskite crystalline structure was identified for all compositions by X-ray diffraction analysis. The basic phase transition temperatures in these ceramics were studied over a wide temperature range. A change in symmetry from a tetragonal to cubic phase was detected, which was further proven by phonon anomalies in composition/temperature-dependent Raman spectra. The incorporation of Sr2+ into BaTiO3 (BT) lead to a shift in the phase transitions to lower temperatures, suppressing the ferroelectric properties and inducing relaxor-like behavior. Therefore, it was reasonable to suppose that the materials progressively lack long-range ordering. The initial second-harmonic generation (SHG) measurements demonstrated that the cubic phase of BST ceramics is not purely centrosymmetric over a wide temperature interval. We discussed the possible origin of the observed effects, and showed that electric field poling seems to reconstruct the structural ordering destroyed by the introduction of Sr2+ to BT. In the first approximation, substitution of Sr for larger Ba simply reduced the space for the off-central shift in Ti in the lattice and hence the domain polarization. A-site cation ordering in BST and its influence on the density of electronic states were also explored. The effect of doping with strontium ions in the BST compound on the density of electronic states was investigated using ab initio methods. As the calculations showed, doping BT with Sr2+ atoms led to an increase in the bandgap. The proposed calculations will also be used in the subsequent search for materials optimal for applications in photovoltaics.
Bacterial microcompartments (BMCs) are prokaryotic organelles involved in several biochemical processes in bacterial cells. These cellular substructures consist of an icosahedral shell and an encapsulated enzymatic core. The outer shells of BMCs have been proposed as an attractive platform for the creation of novel nanomaterials, nanocages, and nanoreactors. In this study, we present a method for functionalizing recombinant GRM2-type BMC shell lumens with short cysteine-containing sequences and demonstrate that the iron and cobalt loading capacity of such modified shells is markedly increased. These results also imply that a passive flow of cobalt and iron atoms across the BMC shell could be possible.
The efflux transporter P-glycoprotein (P-gp) at the blood-brain barrier limits the cerebral uptake of various xenobiotics. To assess the sensitivity of [ ¹¹ C]metoclopramide to measure decreased cerebral P-gp function, we performed [ ¹¹ C]metoclopramide PET scans without (baseline) and with partial P-gp inhibition by tariquidar in wild-type, heterozygous Abcb1a/b (+/−) and homozygous Abcb1a/b (−/−) mice as models with controlled levels of cerebral P-gp expression. Brains were collected to quantify P-gp expression with immunohistochemistry. Brain uptake of [ ¹¹ C]metoclopramide was expressed as the area under the brain time-activity curve (AUC brain ) and compared with data previously obtained with ( R)-[ ¹¹ C]verapamil and [ ¹¹ C] N-desmethyl-loperamide. Abcb1a/b (+/−) mice had intermediate P-gp expression compared to wild-type and Abcb1a/b (−/−) mice. In baseline scans, all three radiotracers were able to discriminate Abcb1a/b (−/−) from wild-type mice (2.5- to 4.6-fold increased AUC brain , p ≤ 0.0001). However, only [ ¹¹ C]metoclopramide could discriminate Abcb1a/b (+/−) from wild-type mice (1.46-fold increased AUC brain , p ≤ 0.001). After partial P-gp inhibition, differences in [ ¹¹ C]metoclopramide AUC brain between Abcb1a/b (+/−) and wild-type mice (1.39-fold, p ≤ 0.001) remained comparable to baseline. There was a negative correlation between baseline [ ¹¹ C]metoclopramide AUC brain and ex-vivo-measured P-gp immunofluorescence (r = −0.9875, p ≤ 0.0001). Our data suggest that [ ¹¹ C]metoclopramide is a sensitive radiotracer to measure moderate, but (patho-)physiologically relevant decreases in cerebral P-gp function without the need to co-administer a P-gp inhibitor.
The role of demand response increases considerably with a higher share of renewable energy sources in the energy mix, characterized with more frequent energy market price fluctuations due to mismatch between uncontrollable weather-dependent production and currently relatively inflexible energy consumption. Reallocation of energy consumption from high-price hours to lower price hours helps to avoid extra costs to the entire economy and ensures the possibility to minimize fossil-based energy generation, therefore contributing to the achievement of zero-emission goals. The research aims to analyze involvement stimulating factors of demand-side management and demand response from the angles of various energy sector participants, identifying barriers and enabling a successful implementation and wider development of this important energy transition facilitator. The qualitative methods are as follows: utilizing the conducted literature review; and scrutinizing scientific publications, reports and legal acts. As a result, the authors point out the five main aspects: pricing mechanisms, incentives, technology, government regulation and customer awareness. Demand response requires spectacular human and technological resources and administrative, financial and educational efforts. However, the demand response addresses many challenges, such as cost savings, innovation, integration of renewable energy sources, effective, stable and safe power grid performance, reduced need for costly infrastructure modifications, and greenhouse gas emission reduction. The abovementioned benefits influence what the demand-response brings, and are crucial for modern society and a successful energy transition.
Recurrent neural networks have flourished in many areas. Consequently, we can see new RNN cells being developed continuously, usually by creating or using gates in a new, original way. But what if we told you that gates in RNNs are redundant? In this paper, we propose a new recurrent cell called Residual Recurrent Unit (RRU) which beats traditional cells and does not employ a single gate. It is based on the residual shortcut connection, linear transformations, ReLU, and normalization. To evaluate our cell’s effectiveness, we compare its performance against the widely-used GRU and LSTM cells and the recently proposed Mogrifier LSTM on several tasks including, polyphonic music modeling, language modeling, and sentiment analysis. Our experiments show that RRU outperforms the traditional gated units on most of these tasks. Also, it has better robustness to parameter selection, allowing immediate application in new tasks without much tuning. We have implemented the RRU in TensorFlow, and the code is made available at
The biorefinery industry is witnessing a transition from fossil and chemical-based processes to more sustainable practices, with a growing emphasis on using renewable resources. Sophorolipids, a promising group of biosurfactants, present a viable substitute for conventionally produced surfactants. This study focuses on microbial fermentation using yeast and lipid substrate for sophorolipid production. The life cycle assessment (LCA) methodology was employed to identify environmental hotspots of the process and to assess the environmental benefits resulting from the replacement of raw rapeseed cooking oil (base scenario) with waste cooking oil, reduction of process electricity consumption, and increased sophorolipid yield. By compiling scenarios with the lowest environmental impact, a best-case scenario was created. The results revealed that the environmental impact of sophorolipid production could be reduced by 50% in the best-case scenario compared to the base scenario. This research provides valuable insights into the environmental optimization of the fermentation process and through the application of LCA highlights the potential for the reduction of negative environmental impact of sophorolipid production, contributing to the ongoing transition from petroleum oil and petrochemical refineries to sustainable biorefineries.
While the bulk strontium titanate (STO) crystal characteristics are relatively well known, ultrathin perovskites’ nanostructure, chemical composition, and crystallinity are quite complex and challenging to understand in detail. In our study, the DFT methods were used for modelling the Raman spectra of the STO bulk (space group I4/mcm) and 5–21-layer thin films (layer group p4/mbm) in tetragonal phase with different thicknesses ranging from ~0.8 to 3.9 nm. Our calculations revealed features in the Raman spectra of the films that were absent in the bulk spectra. Out of the seven Raman-active modes associated with bulk STO, the frequencies of five modes (2Eg, A1g, B2g, and B1g) decreased as the film thickness increased, while the low-frequency B2g and higher-frequency Eg modes frequencies increased. The modes in the films exhibited vibrations with different amplitudes in the central or surface parts of the films compared to the bulk, resulting in frequency shifts. Some peaks related to bulk vibrations were too weak (compared to the new modes related to films) to distinguish in the Raman spectra. However, as the film thickness increased, the Raman modes approached the frequencies of the bulk, and their intensities became higher, making them more noticeable in the Raman spectrum. Our results could help to explain inconsistencies in the experimental data for thin STO films, providing insights into the behavior of Raman modes and their relationship with film thickness.
The linear stability of a convective flow in a vertical fluid layer caused by nonlinear heat sources in the presence of cross-flow through the walls of the channel is investigated in this paper. This study is relevant to the analysis of factors that affect the effectiveness of biomass thermal conversion. The nonlinear problem for the base flow temperature is investigated in detail using the Krasnosel’skiĭ–Guo cone expansion/contraction theorem. It is shown that a different number of solutions can exist depending on the values of the parameters. Estimates for the norm of the solutions are obtained. The linear stability problem is solved numerically by a collocation method based on Chebyshev polynomials. It is shown that the increase in the cross-flow intensity stabilizes the flow, but there is also a small region of the radial Reynolds numbers where the flow is destabilized.
Our paper considers the possibility of the emergence and control of non-equilibrium states of a quasi-homogenous condensed medium with energy and particle flows in the phase space, which, first of all, manifest themselves in the explosive development of the asymmetry in the initially symmetric equilibrium system. This symmetry breaking and the appearance of non-equilibrium in the system are controlled by the coherent acceleration of the system. Dependencies of thermodynamic parameters of a strong nonequilibrium system on the indices of disequilibrium in coherently correlated states are given, and the estimates of the dielectric permittivity in a non-equilibrium system and modes of plasma acoustic oscillations are made. An estimate of the superconducting transition temperature under nonequilibrium conditions has been made. It is demonstrated that the superconducting transition temperature can approach the limiting value, corresponding to a quantum with its plasma frequency of the medium.
Managing chronic non-healing wounds (CNW) is a time-consuming process accompanied by economic loss. The combination of drug-resistant microflora that is able to organize in a biofilm is the main factor of wound chronicity that requires novel treatment strategies. The current study presents the results of silver nanoparticles (AgNPs) application accompanied by low-frequency ultrasound (US) in the rat model of a purulent CNW. As a result, using AgNPs and low-frequency US demonstrated positive dynamics of wound healing and a reduction in all phases of the wound process. The combined use of AgNPs and low-frequency US made it possible to reduce the time of necrosis rejection by 6.5 days (p < 0.05), and the appearance of granulations and epithelial tissue by 3.7 and 4.7 days (p < 0.05), respectively. Simultaneous treatment by the AgNPs with low-frequency US of the purulent CNW showed accelerative tissue regeneration processes, compared to separate AgNPs or US and chlorhexidine treatment methods. A synchronous application of AgNPs with US treatment significantly improves chronic purulent wound healing and reduces the treatment period. The effectiveness of the treatment method is achieved mainly due to the bactericidal properties of AgNPs and the cleansing effect of ultrasonic cavitation.
The school-to-work transition is one of the trickiest steps in the life cycle of an individual because when young people complete their education and enter the labor market, they have to compete to attain a job while lacking the job experience or skills required by employers. Across European countries, the school-to-work transition shows very different characteristics and durations, stemming from, among other factors, (1) the different provisions of services at the country level to help young people become oriented in the labor market, (2) different historical backgrounds, and even (3) the different capacities of education systems to provide the skills required by employers, despite the efforts to homogenize the national education systems, which started with the Bologna process. In this paper, we aim to compare various programs implemented within formal education at the macro-level in Italy, Moldova, and Latvia, three rather different countries in Europe, that have the goal of helping young people during various stages of this transition. The conclusion we can draw is that each of these countries needs to adopt a coordinated and integrated strategy of reforms aimed at (a) preventing early school drop-outs; (b) incentivizing the attainment of a university degree; (c) reforming school curricula; (d) closing the gap between education systems and labor market requirements; and (e) improving the services that help young people during the school-to-work transition.
Open source GIS software GRASS releases 8.0 to 8.4 have received some long overdue improvements in imagery handling such as the ability to reuse spectral signature files of existing classifiers, machine readable output of accuracy assessment tool and a support vector machine (SVM) classifier. Practical comparison of all three pixel‐based classifiers of GRASS GIS indicated that the maximum likelihood discriminant analysis classifier is the fastest and least accurate one, followed by a sequential maximum a posteriori classifier with reasonably fast execution time and good accuracy. The newly added SVM classifier is the slowest one but provides the highest accuracy and also shows the highest improvement potential by hyperparameter optimization. To illustrate the capabilities of the core classifiers, a showcase is presented where a single Sentinel 2 image is classified to distinguish 18 crop types using all three classifiers available in GRASS.
The relation between social capital and socio‐economic wealth is a highly debated topic in development studies. This article aims at investigating the relationship between personal wealth and trust. It combines social capital with social categorization theory through a structural equation model based on a data set of over 1000 observations collected in the Republic of Latvia, on the basis of stratified sampling, in 2010, in the wake of a deep financial and economic crisis. Main results suggest evidence of an indirect relationship between wealth and interpersonal trust, with institutional trust and social engagement as mediating factors. This evidence is tested for residence place dimensions, ethno‐linguistic affiliation, education and income. Main results hold for poorer, less educated and rural respondents, whereas significant discrepancies arise for urban respondents. Finally, results highlight the interplay of socio‐economic dimensions and social and cultural identity. This suggests the existence of different dynamics of social capital accumulation at play, depending on various socio‐demographic and socio‐economic dimensions.
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4,896 members
Vyacheslavs Kashcheyevs
  • Faculty of Physics and Mathematics
Mihails Hazans
  • Faculty of Business Management and Economics
Olga Muter
  • Faculty of Biology
Reinis Rutkis
  • Institute of Microbiology and Biotechnology
Raiņa bulvāris 19, LV 1586, Riga, Latvia
Head of institution
Indriķis Muižnieks
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