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Abstract Background 6 − 4 photoproducts are the second most common UV-induced DNA lesions after cyclobutane pyrimidine dimers. In plants, they are mainly repaired by photolyases in a process called photoreactivation. While pyrimidine dimers can be deleterious, leading to mutagenesis or even cell death, 6 − 4 photoproducts can activate specific signaling pathways. Therefore, their removal is particularly important, especially for plants exposed to high UV intensities due to their sessile nature. Although photoreactivation in nuclear DNA is well-known, its role in plant organelles remains unclear. In this paper we analyzed the activity and localization of GFP-tagged AtUVR3, the 6 − 4 photoproduct specific photolyase. Results Using transgenic Arabidopsis with different expression levels of AtUVR3, we confirmed a positive trend between these levels and the rate of 6 − 4 photoproduct removal under blue light. Measurements of 6 − 4 photoproduct levels in chloroplast and nuclear DNA of wild type, photolyase mutants, and transgenic plants overexpressing AtUVR3 showed that the photoreactivation is the main repair pathway responsible for the removal of these lesions in both organelles. The GFP-tagged AtUVR3 was predominantly located in nuclei with a small fraction present in chloroplasts and mitochondria of transgenic Arabidopsis thaliana and Nicotiana tabacum lines. In chloroplasts, this photolyase co-localized with the nucleoid marked by plastid envelope DNA binding protein. Conclusions Photolyases are mainly localized in plant nuclei, with only a small fraction present in chloroplasts and mitochondria. Despite this unbalanced distribution, photoreactivation is the primary mechanism responsible for the removal of 6 − 4 photoproducts from nuclear and chloroplast DNA in adult leaves. The amount of the AtUVR3 photolyase is the limiting factor influencing the photoreactivation rate of 6 − 4 photoproducts. The efficient photoreactivation of 6 − 4 photoproducts in 35S: AtUVR3-GFP Arabidopsis and Nicotiana tabacum is a promising starting point to evaluate whether transgenic crops overproducing this photolyase are more tolerant to high UV irradiation and how they respond to other abiotic and biotic stresses under field conditions.

Abstract Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) catalyzes the first step of carbon fixation performed by photosynthetic organisms. Form I of this enzyme found in plants and cyanobacteria is composed of eight large (RbcL) and eight small (RbcS) subunits. To form a functional enzyme, Rubisco subunits need to be properly folded, with the assistance of cellular chaperone machinery, and consecutively assembled in a strictly orchestrated manner, with the help of multiple auxiliary factors. In recent years, multiple Rubisco assembly chaperones and their function in enzyme biogenesis have been extensively characterized. Little is known about the potential specialized factors involved in Rubisco subunits folding at the pre-chaperonin stage, yet this knowledge is greatly needed for the fast and efficient testing of new Rubisco variants. Synechococcus sp. PCC 6803 Rubisco shows limited solubility and a lack of assembly in the Escherichia coli expression system. In this study, we aim to identify which additional chaperones are necessary and sufficient in sustaining the heterologous assembly of native Rubisco. Our findings prove that upon the introduction of Synechocystis DnaK2 to the E. coli system, RbcL is produced in soluble form. The addition of specific DnaJ (Sll1384) enhances this effect. We explain these combined effects based on binding constancies, measured for particular partners in vitro, as well as our analysis of the putative tertiary structure of the proteins. Our results have potential implications for Rubisco engineering.

Controlled junctions of proteins and nanomaterials offer multiple potential applications in the further construction of nanobiodevices. One of the possible junction types is a set of sequential monolayers of various components deposited on a given substrate. The advantage of such an organization is its high sensitivity, resulting from a huge surface covered by molecules or particles. What is more, the molecules/particles adsorbed on a substrate might be easier to handle than the assay in a cuvette. For further application, there should be crosstalk between monolayers; this is defined by the type of individuals forming a complex system. Here, we are studying, using mainly confocal microscopy and FLIM imaging, crosstalk through resonance energy transfer. The sequential monolayers of fluorescent proteins and CdTe quantum dots were deposited on a convenient substrate, a polyvinylidene difluoride membrane. First, we found that the degree of coverage is lower in the second monolayer. Hence, by manipulating the order of deposition, we obtained a system with a varied yield of resonance energy transfer with a donor excess or an acceptor excess. For a deeper understanding of the energy transfer and its limitations in this system influencing the assay pursuit, we utilized Monte Carlo computation. We found that, indeed, the distance between the monolayers, as well as the degree of coverage, is crucial. With the results of the simulation, we might estimate the relative degree of coverage in our sequential monolayers. We also found that in quantum-dots/protein-composed systems, the yield is stronger than predicted by Monte Carlo simulation. Hence, there should be protein reorientation on the nanoparticle surface, leading to such an effect. Finally, we showed that the yield of resonance energy transfer may be modulated by the external application of poly-L-lysines. These chemicals influenced QD fluorescence but not protein fluorescence and might be used, therefore, as a trigger or a switch in nanobiodevices employing those types of sequential monolayers.

Colloidal semiconductor quantum dots (QD), as well as other nanoparticles, are useful in cell studies as fluorescent labels. They may also be used as more active components in various cellular assays, serving as sensors or effectors. However, not all QDs are biocompatible. One of the main problems is their outer coat, which needs to be stable and to sustain hydrophilicity. Here we show that purpose-designed CdSe QDs, covered with a Puf protein, can be efficiently accumulated by HeLa cells. The uptake was measurable after a few hours of incubation with nanoparticles and most of the fluorescence was localised in the internal membrane system of the cell, including the endoplasmic reticulum and the Golgi apparatus. The fluorescence properties of QDs were mostly preserved, although the maximum emission wavelength was slightly shifted, and the fluorescence lifetime was shortened, indicating partial sensitivity of the QDs to the cell microenvironment. QD accumulation resulted in a decrease in cell viability, which was attributed to disturbance of endoplasmic reticulum performance.

Photosynthesis is the basic process for life on Earth—and the one that has changed life history most drastically [...]

Plastoglobules (PGs) might be characterised as microdomains of the thylakoid membrane that serve as a platform to recruit proteins and metabolites in their spatial proximity in order to facilitate metabolic channelling or signal transduction. This study provides new insight into changes in PGs isolated from two plant species with different responses to chilling stress, namely chilling-tolerant pea (Pisum sativum) and chilling-sensitive bean (Phaseolus coccineus). Using multiple analytical methods, such as high-performance liquid chromatography and visualisation techniques including transmission electron microscopy and atomic force microscopy, we determined changes in PGs’ biochemical and biophysical characteristics as a function of chilling stress. Some of the observed alterations occurred in both studied plant species, such as increased particle size and plastoquinone-9 content, while others were more typical of a particular type of response to chilling stress. Additionally, PGs of first green leaves were examined to highlight differences at this stage of development. Observed changes appear to be a dynamic response to the demands of photosynthetic membranes under stress conditions.

Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) is one of the best studied enzymes. It is crucial for photosynthesis, and thus for all of biosphere’s productivity. There are four isoforms of this enzyme, differing by amino acid sequence composition and quaternary structure. However, there is still a group of organisms, dinoflagellates, single-cell eukaryotes, that are confirmed to possess Rubisco, but no successful purification of the enzyme of such origin, and hence a generation of a crystal structure was reported to date. Here, we are using in silico tools to generate the possible structure of Rubisco from a dinoflagellate representative, Symbiodinium sp. We selected two templates: Rubisco from Rhodospirillum rubrum and Rhodopseudomonas palustris. Both enzymes are the so-called form II Rubiscos, but the first is exclusively a homodimer, while the second one forms homo-hexamers. Obtained models show no differences in amino acids crucial for Rubisco activity. The variation was found at two closely located inserts in the C-terminal domain, of which one extends a helix and the other forms a loop. These inserts most probably do not play a direct role in the enzyme’s activity, but may be responsible for interaction with an unknown protein partner, possibly a regulator or a chaperone. Analysis of the possible oligomerization interface indicated that Symbiodinium sp. Rubisco most likely forms a trimer of homodimers, not just a homodimer. This hypothesis was empowered by calculation of binding energies. Additionally, we found that the protein of study is significantly richer in cysteine residues, which may be the cause for its activity loss shortly after cell lysis. Furthermore, we evaluated the influence of the loop insert, identified exclusively in the Symbiodinium sp. protein, on the functionality of the recombinantly expressed R. rubrum Rubisco. All these findings shed new light onto dinoflagellate Rubisco and may help in future obtainment of a native, active enzyme.

Senescence is the final stage of plant development, affecting individual organs or the whole organism, and it can be induced by several environmental factors, including shading or darkness. Although inevitable, senescence is a complex and tightly regulated process, ensuring optimal remobilization of nutrients and cellular components from senescing organs. Photoreceptors such as phytochromes and cryptochromes are known to participate in the process of senescence, but the involvement of phototropins has not been studied to date. We investigated the role of these blue light photoreceptors in the senescence of individually darkened Arabidopsis thaliana leaves. We compared several physiological and molecular senescence markers in darkened leaves of wild-type plants and phototropin mutants (phot1, phot2, and phot1phot2). In general, all the symptoms of senescence (lower photochemical activity of photosystem II, photosynthetic pigment degradation, down-regulation of photosynthetic genes, and up-regulation of senescence-associated genes) were less pronounced in phot1phot2, as compared to the wild type, and some also in one of the single mutants, indicating delayed senescence. This points to different mechanisms of phototropin operation in the regulation of senescence-associated processes, either with both photoreceptors acting redundantly, or only one of them, phot1, playing a dominant role.

When improving soil shear strength using various materials, determination of the improvement rate is a key issue and can be carried out using a direct shear test (DST). However, many standards for DST require only three specimens in the test and do not deal with test result uncertainty. In this study, shear strength parameters of clay of intermediate plasticity (CI) and sandy clays (CS1, CS2) improved with the addition of polyester fibres of 70 mm in length in amounts of 0.5%, 1.0%, and 1.5% of dry soil mass were obtained using DST with a shear box of size 0.3 m × 0.3 m × 0.08 m. The results show that using fibres provides significant improvement and the number of tested specimens (three or four) in DST has a significant impact on the obtained values of shear strength parameters. It is not recommended to carry out DST with only three specimens. The analysis of uncertainty shows that covariance between correlated input quantities (normal stresses and shear stresses) has a negligible influence on result uncertainty. The worst-case estimated uncertainties are very high and should not be applied. Analysis of the state of the fibre surface before and after shearing using scanning electron microscopy (SEM) shows that suitable fibre scratch resistance may be the reason for the large improvement.

The article aims to show that there are determinants of consumer behavior in Chinese society that remain relevant regardless of the direction of global social changes - caused by the digital transformation of society and economy, the development of artificial intelligence and unexpected events such as pandemics. The factors influencing consumption in China undoubtedly include culture, politics, as well as macroeconomic factors influencing the level and pace of consumption development. It is worth analyzing consumer behavior using interdisciplinary knowledge and bearing in mind the complex and diverse changes taking place on a national scale, and the emergence of new terminology is a reflection of the changing specificity of consumption in China. Awareness of the dynamics of changes in the behavior of Chinese consumers will not only facilitate business relations with Chinese contractors, but will also help determine the direction of consumption development at the global level, as the possibilities of e-commerce developing in China are also used and tested in Europe.

The paper describes a method of modifying a commercial viscose nonwoven fabric and its use as a modern mulching material in agriculture. The conducted research confirmed that the proposed modification of the viscose nonwoven fabric could be successfully used as a multipurpose and, above all, completely biodegradable nonwoven crop cover, which will eliminate the problem of disposal after the harvest period. Modified cellulose nonwoven fabric was obtained by staining with NB—BT helion brown, then padding with potassium nitrate (KNO3) solution (used as a fertilizer) and finally coating with polylactide (PLA) solution. The characterisation of the nonwoven fabric included structural analysis, physicochemical properties and mechanical tests. The modified cellulose nonwovens were used in the tunnel cultivation of tomatoes as a heat-retardant, water-absorbing, antiweed mulching material that prevents soil infestation and slowly releases fertilizers.

Using materials from recycling is a key part of decreasing present-day waste. It is optimal for recycled material to be used in environmental protection. This paper presents the application of geotextile ropes in erosion protection of a slope of a gravel pit. To protect the slope, thick ropes with a diameter of 120 mm made from wool and a mixture of recycled natural and synthetic fibers were used. After 47 months from installation, soil and rope specimens were taken from the slope parts with inclinations 1:1 and 1:1.8, and their physical and mechanical properties were determined. Direct shear tests were applied to determine the soil shear strength parameters in state at sampling and at Ic = 0 (unconsolidated and consolidated). Based on the obtained soil shear strength parameters, the loads on the ropes were determined, taking into account also unfavorable hydraulic conditions and compared to rope strength. It was shown that even after 47 months from installation, rope tension strength was higher as tension forces were induced in the ropes in every case. At present, whole slopes in protected sections are stabilized, without rills and gullies.

The aim of the study was to assess the possibility of using polyurethane foams (PUF) as a filling of a foam-sand filter to directly treat domestic sewage with increased content of ammonium nitrogen and low organic carbon to nitrogen ratio (C/N). The study compared performance of two types of flexible foams: new, cylinder-shaped material (Novel Foams, NF) and waste, scrap foams (Waste Foams, WF). The foams serving as a filling of two segments of a foam-sand filter were assessed for their hydrophobic and physical properties and were tested for their cell structure, i.e., cell diameter, cell size distribution, porosity, and specific surface area. The study accounted also for selected application-related properties, such as hydrophobicity, water absorption, apparent density, dimensional stability, amount of adsorbed biomass, and the possibility of regeneration. Cell morphology was compared in reference foams, foams after 14 months of the filter operation, and regenerated foams. The experimental outcomes indicated WF as an innovative type of biomass carrier for treating domestic sewage with low C/N ratio. SEM images showed that immobilization of microorganisms in NF and WF matrices involved the formation of multi-cellular structures attached to the inner surface of the polyurethane and attachment of single bacterial cells to the foam surface. The amount of adsorbed biomass confirmed that the foam-sand filter made up of two upper layers of waste foams (with diameters and pore content of 0.50–1.53 mm and 53.0–63.5% respectively) provided highly favorable conditions for the development of active microorganisms.

The paper presents the options available when selecting equivalents of the Chinese term 机关 jīguān in legal context. The author undertook the conceptual analysis of the potential German and Polish equivalents of 机关 applied in the General Principles of the Civil Law of the People’s Republic of China of April 12, 1986 (中华人民共和国民法通则 Zhōnghuá Rénmín Gònghéguó mínfă tōngzé) and Civil Procedure Law of the People’s Republic of China of April 9, 1991 (中华人民共和国诉讼法 Zhōnghuá Rénmín Gònghéguó mínshì sùsòng fă). The corpus under study included the translation of the mentioned statutes into English proposed by Centre of Laws and Regulations in Law Press China (法规中心，法律出版社 Făguī zhōngxīn, Fălǜ chūbănshè). English and German are often intermediary languages in the process of finding equivalents in Polish-Chinese translation. The term 机关 used in a legal and/or administrative context is translated into English, German and Polish differently depending on the context.

Nazwy nieostre i klauzule generalne stanowią prawdziwe wyzwanie dla tłumacza tekstów prawnych, od którego wiedzy prawnej i pozaprawnej zależy odpowiednia ich interpretacja i przekład. Badania terminologiczne i prawnoporównawcze świadczą o tym, że wiele nazw nieostrych i klauzul generalnych występujących w paralelnych tekstach prawnych, ze względu na otoczenie różnych systemów prawnych i odmiennych kultur, nabiera różnych znaczeń. Przedmiotem rozważań autorki są stanowiska prawników i tłumaczy tekstów prawnych dotyczące swoistych cech nazw nieostrych oraz klauzul generalnych, jak również występujących pomiędzy nimi różnic w zakresie pól znaczeniowych. Celem autorki jest potwierdzenie konieczności przeprowadzenia badań w zakresie chińskich nazw nieostrych i klauzul generalnych.

Celem artykułu jest wyodrębnienie chińskich środków językowych zastosowanych w wybranych przepisach ustawowych, które pozwalają na zachowanie przejrzystej konstrukcji aktów prawotwórczych i ich komunikatywności. Ponieważ autorka nie znalazła wśród chińskich regulacji dotyczących podstawowych zasad legislacji typologii przepisów i stosowanych w nich środków językowych, postanowiła odnaleźć je w wybranych chińskich przepisach i przetłumaczyć na język polski. W tym celu autorka dokonała analizy tekstów paralelnych w oparciu o pragmatyczny model tłumaczenia terminów prawnych Kierzkowskiej. Korpus badawczy stanowiły fragmenty aktów prawotwórczych polskich i chińskich, zawierające przepisy nowelizujące, odsyłające, uchylające, przepisy o wejściu ustawy w życie i przepisy o zakresie zastosowania. Wyniki przeprowadzonej analizy pozwalają stwierdzić, że chiński ustawodawca tworząc przepisy stosuje swoisty i mało rozbudowany katalog środków językowych. Autorka przedstawiła je w niniejszym artykule.

The main issue of the paper is the phenomenon of polysemy, which is present in the Chinese, German, Greek and Polish legal languages. The phenomenon is seen as the criterion of comparative studies between the specified legal languages. As polysemy is often discussed together with homonymy, the authors have decided to define polysemy in the introduction of the text, on the basis of etymology and being contrary to homonymy. The first assumption is an existence of the polysemy of certain terms (words and syntagmas), which relies on simultaneous existence of the term both in general (lay) language and in language for special purposes. The LSP may be the legal language, for example. Based on the existing research of legal language, the authors assume polysemy does not have a homogenous character as a term and moreover this is confirmed by various legilinguistic classifications. There are typologies of legal language based on the criterion of source text, but the authors also propose the consideration of a classification performed on the basis of various fields of law i.e. civil law, constitutional law, criminal law together with confirmation of classification. This criterion may be very useful when explaining the polysemy of legal terms as it originates not only from different types of legal texts, but primarily comes from legal fields. The performed comparative analysis of selected legal terms of different Chinese, German, Greek and Polish legal fields indicates that the multiplicity of meanings of the same term (word/syntagma) comes from the presence of this term in different legal fields. Simultaneously, the primarily assumed statement of the existence of polysemy in the frame of a certain language for special purposes, i.e. legal language, is confirmed. This assumption may be a valuable aspect of further research of national legal languages and may be useful for the users of legal language such as legal translators or legal comparatists.

Th is paper discusses the main sources of ambiguity in Chinese-Polish translation of the contract legal language. Legal Chinese is very often the same as ordinary formal Chinese and that fact causes ambiguity in Chinese contracts. Th e author focuses on polysemy and homonymy which make the interpretation of legal language diffi cult and ambiguous. The meaning of Chinese characters depends on the textual context. However, when an interpreter does not know the background information of translated legal texts, it is very diffi cult to achieve a high quality legal translation. The abundance of homophones in Chinese language also poses a problem, especially in the case of contracts concluded in words, not in writing. The paper further presents different grammatical functions of Chinese terms encountered in contracts without a morphological change. Such linguistic features of Chinese language as: the absence of distinction between singular and plural nouns, lack of infl ection, no grammatical categories of tense and aspect cause ambiguity and vagueness in interpreting the Chinese agreements. Moreover, the understanding of such texts is sometimes incorrect due to omissions and elliptical sentences. The author also shows the diff erences in the meaning of terms, which apparently signify the same entities and concepts in Polish and Chinese legal languages but in fact diff er signifi cantly.