Search Results (4,207)

Frankenia is a morphologically complex genus, with some species exhibiting a few diagnostic characters and significant morphological variability. This has led to misidentification or the synonymisation of many names based on one or a few diagnostic traits. This phenomenon affects the annual sea-heath, F. pulverulenta, a Eurasian–Mediterranean herb that has become subcosmopolitan, to which several entities have been included due to their shared features, namely their annual lifespan or their flattened leaves. However, this fact also extends to shrubby species, such as the Madeiran F. cespitosa. Here, integrative taxonomic studies, encompassing detailed morphological descriptions of macro- and microcharacters along with molecular phylogenetic analyses of both nuclear ribosomal (ITS1-5.8S-ITS2 region) and plastid (matK gene) DNA sequence data, and an analysis of biogeographic data were undertaken. This examination has resulted in the most complete phylogenetic trees of Frankenia to date, leading to the reinstatement of two African species broadly differing morphologically from F. pulverulenta. Firstly, F. florida L.Chevall., a name applied to a species occurring in the Saharan regions of Algeria, Morocco, Mali, and Mauritania, is often accepted as a variety or subspecies of the annual sea-heath. In contrast, F. densa Pohnert, a species endemic to Namibia and northern South Africa, has been synonymised with F. pulverulenta. However, since those two names were later homonyms of two Chilean and Australian plants, they were deemed illegitimate upon publication. Consequently, two new names are proposed for them: F. sahariensis and F. dinteri, respectively. Their substantiation as independent species is provided by data on their morphology, distribution, ecology, and molecular phylogenetics, which demonstrate their distinctiveness from F. pulverulenta. Nomenclatural synonymy and types are also presented for all concerned names, including the designation of two new lectotypes. Furthermore, the importance of an accurate description of the morphological variation in populations is emphasised for a precise identification of taxa in Frankenia. Full article

(1→3)-α-d-Glucan is an important component of the cell wall of most fungi. The polymer has many applications, including as a therapeutic agent in the prevention or treatment of various diseases, as well as a heavy metal sorbent and a component of new materials used in the plastics industry. The presence of (1→3)-α-d-glucan (water-insoluble, alkali-soluble polysaccharide) in the cell wall of Pleurotus djamor (pink oyster mushroom) was confirmed using specific fluorophore-labeled antibodies. Therefore, the water-insoluble fraction (WI-ASF) of P. djamor B123 fruiting bodies was isolated by alkaline extraction and used for further analyses. The structural features of the WI-ASF were determined by composition analysis, linkage analysis, Fourier transform infrared and Raman spectroscopy, ¹H and ¹³C nuclear magnetic resonance spectroscopy, scanning electron microscopy, as well as viscosity, specific rotation, and gel permeation chromatography. These studies revealed the presence of glucose units linked by α-glycosidic bonds and scanty amounts of mannose and xylose. Furthermore, methylation analysis of WI-ASF demonstrated that the (1→3)-linked glucopyranose (Glcp) is the primary moiety (86.4%) of the polymer, while the 3,4- and 3,6-substituted hexoses are the branching residues of the glucan. The results of chemical and spectroscopic investigations indicated that the analyzed WI-ASF is a (1→3)-linked α-d-glucan type with a molecular weight of 552 kDa. Full article

Honeybees are of economic importance not only for honey production, but also for crop pollination, which amounts to USD 20 billion per year in the United States. However, the number of honeybee colonies has declined more than 40% during the last few decades. Although this decline is attributed to a combination of factors (parasites, diseases, pesticides, and nutrition), unlike other factors, the effect of nutrition on honeybee health is not well documented. In this study, we assessed the differential expression of seven genes linked to honeybee health under three different diets. These included immune function genes [Cactus, immune deficiency (IMD), Spaetzle)], genes involved in nutrition, cellular defense, longevity, and behavior (Vitellogenin, Malvolio), a gene involved in energy metabolism (Maltase), and a gene associated with locomotory behavior (Single-minded). The diets included (a) commercial pollen patties and sugar syrup, (b) monofloral (anise hyssop), and (c) polyfloral (marigold, anise hyssop, sweet alyssum, and basil). Over the 2.7-month experimental periods, adult bees in controls fed pollen patties and sugar syrup showed upregulated Cactus (involved in Toll pathway) and IMD (signaling pathway controls antibacterial defense) expression, while their counterparts fed monofloral and polyfloral diets downregulated the expression of these genes. Unlike Cactus and IMD, the gene expression profile of Spaetzle (involved in Toll pathway) did not differ across treatments during the experimental period except that it was significantly downregulated on day 63 and day 84 in bees fed polyfloral diets. The Vitellogenin gene indicated that monofloral and polyfloral diets significantly upregulated this gene and enhanced lifespan, foraging behavior, and immunity in adult bees fed with monofloral diets. The expression of Malvolio (involved in sucrose responsiveness and foraging behavior) was upregulated when food reserves (pollen and nectar) were limited in adult bees fed polyfloral diets. Adult bees fed with monofloral diets significantly upregulated the expression of Maltase (involved in energy metabolisms) compared to their counterparts in control diets to the end of the experimental period. Single-Minded Homolog 2 (involved in locomotory behavior) was also upregulated in adult bees fed pollen patties and sugar syrup compared to their counterparts fed monofloral and polyfloral diets. Thus, the food source significantly affected honeybee health and triggered an up- and downregulation of these genes, which correlated with the health and activities of the honeybee colonies. Overall, we found that the companion crops (monofloral and polyfloral) provided higher nutritional benefits to enhance honeybee health than the pollen patty and sugar syrup used currently by beekeepers. Furthermore, while it has been reported that bees require pollen from diverse sources to maintain a healthy physiology and hive, our data on nuclear colonies indicated that a single-species diet (such as anise hyssop) is nutritionally adequate and better or comparable to polyfloral diets. To the best of our knowledge, this is the first report indicating better nutritional benefits from monofloral diets (anise hyssop) over polyfloral diets for honeybee colonies (nucs) in semi-large-scale experimental runs. Thus, we recommend that the landscape of any apiary include highly nutritious food sources, such as anise hyssop, throughout the season to enhance honeybee health. Full article

Copper has been proposed as a container material for the disposal of used nuclear fuel in a number of countries worldwide. The container materials will be subject to various corrosion processes in a deep geological repository, including radiation-induced corrosion (RIC) resulting from the γ-irradiation of the near-field environment. A comprehensive model is being developed to predict the extent of RIC by coupling a radiolysis model to the interfacial electrochemical reactions on the container surface. An important component of the overall model is a radiolysis model to predict the time-dependent concentration of oxidizing and reducing radiolysis products. As a first step in the model development, various radiolysis models have been validated against experimental measurements of the concentrations of dissolved and gaseous radiolysis products. Experimental data are available for pure H₂O- and Cl⁻-containing solutions, with and without a gas headspace. The results from these experiments have been compared with predictions from corresponding radiolysis models, including the effects of the partitioning of gaseous species (O₂ and H₂) at the gas–solution interface. Different reaction schemes for the Cl⁻ radiolysis models are also compared. The validated radiolysis model will then be coupled with interfacial reactions on the copper surface and additional processes related to the presence of bentonite clay in Steps 2 and 3 of the overall model, respectively. Full article

Research into the effects of long-term antioxidant supplementation on the islet microenvironment is limited. This study examined whether long-term N-acetyl-L-cysteine (NAC) supplementation can prevent changes in metabolic outcomes, beta cell function, and pancreatic stellate cell (PaSC) activation in aging mice. Male C57BL/6N mice at 18 weeks were administered 50 mM NAC through their daily drinking water and treated for up to 60 weeks. Aging NAC mice displayed lower body weights and improved glucose tolerance but reduced insulin secretion and insulin signaling compared to control (ND) mice. When some 40-week-old ND and NAC mice were subjected to 8 weeks of a high-fat diet (HFD)-stress challenge, results showed that NAC reduced HFD-induced beta cell oxidative stress and preserved nuclear PDX-1 expression. The findings from this study suggest that while NAC can be beneficial for diet-induced stress during aging, the effects of long-term NAC on the islets of physiologically aging mice are more ambiguous. Further exploration is required to determine the effects of NAC-mediated lowering of beta cell oxidative stress on insulin secretion and signaling pathways. This study highlights the importance of investigating oxidative stress balance in aging islets under normal diet conditions to determine if antioxidative therapies can be utilized without interfering with essential physiological processes. Full article

Nuclear thermal propulsion, which uses a reactor core as the energy source of a nuclear thermal rocket, is expected to become an effective means of deep space exploration in the future. The reactor core can be damaged by a large temperature gradient. Thus, investigating the structural distribution of its internal components and understanding its flow and heat transfer characteristics is highly important. In this study, a 19-hole hollow hexagonal prism fuel element is selected for simulation. A new type of fuel element is proposed by changing the diameter of the channels in the work material, and the heat transfer characteristics are compared and analyzed. Compared with a conventional fuel element under uniform inlet conditions, when the inlet conditions and the diameter of the channel in the work material are changed, the peak temperature inside the fuel element decreases, but the overall temperature distribution is more uniform. Along the flow direction, the temperature distribution boundary is located at y = 300–500 mm. From the inlet to this position, the temperature distribution on the axial cross-section is uniform. From this position to the outlet, the temperature difference along the radial cross-section is significantly reduced, and the temperature fluctuation at the periphery of the fuel element is significantly improved. The research results can provide a reference for the design of fuel elements. Full article

Donkeys and mules have historically played an important role in agriculture and are now gaining recognition for their contributions to animal conservation, milk production, tourism, and equid-assisted services. However, their distinctive reproductive challenges pose obstacles to breeding management. As a result, the application of assisted reproductive technologies (ARTs) could help address these challenges, enhancing their roles in both traditional and emerging industries. This review examines the current and emerging in vitro techniques for breeding donkeys and mules. Key methodologies such as sperm cryopreservation, innovative sperm preservation technologies, embryo transfer, ovum pick-up (OPU), oocyte maturation, and vitrification are discussed, emphasizing their importance in optimizing ARTs. Advances in in vitro embryo production technologies such as in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), and somatic cell nuclear transfer (SCNT) are reviewed, with particular attention to its success in producing the first donkey and mule blastocysts or foals. Despite significant progress in the last decade, standardization of protocols for gamete conservation and embryo transfer are still required in long-ear equids. Advancing these technologies in combination with established in vitro embryo production could significantly improve reproductive outcomes and enhance the genetic management of donkey and mule populations. Full article

This review paper aims to present a comprehensive overview of the evaluation, simulation, and control of heating, ventilation, and air conditioning (HVAC) systems in nuclear power plants (NPPs), specifically highlighting their importance in maintaining operational safety, thermal performance, and energy efficiency. The study’s authors summarize recent developments in HVAC technologies, such as passive cooling systems, data-driven energy management frameworks, and intelligent control strategies, to cope with the specific challenges of NPPs. Various passive cooling systems, including heat pipes, thermosyphons, and loop heat pipes, have proven themselves by their ability to remove residual heat from spent fuel pools and reactors power plants with high efficiency. Through experimental studies, they have shown their ability to eliminate operational vulnerability to accidents or guarantee any desired long-term cooling. Intelligent sensor networks allow a more data-driven approach to HVAC control, enabling online energy management frameworks and advanced intelligent control systems. These exhibit considerable promise for optimizing HVAC performance, decreasing energy consumption, and improving operational flexibility in multi-zone systems. Such capabilities are ideal for addressing the dynamic and safety-critical nature of NPPs. They are first enabled by the use of these technologies for real-time monitoring, predictive maintenance, and adaptive control. When applied with advanced HVAC control systems, passive cooling techniques provide an exciting route to improve safety and energy efficiency. An overview of the key findings is that robust thermal management solutions combined with intelligent control and intelligent adaptation are essential when addressing the rapidly evolving demands of nuclear energy systems. This work highlights the priorities in the next generation of nuclear power plants, which should actively pursue seamless integration of out-of-system technologies into existing NPP infrastructures, enabling scalable, cost-effective, and resilient solutions. Full article

Uranium–niobium (U-Nb) alloys, used in a variety of industrial and energy applications that require high density, ductility, and good corrosion resistance, comprise a highly complex, multiphasic system with a phase diagram well established through decades of extensive experimental and theoretical research. They are also one of the best candidates for a metallic fuel alloy with high-temperature strength sufficient to support the core, acceptable nuclear properties, good fabricability, and compatibility with usable coolant media. The key factor determining the performance and safety of a metallic fuel such as U-Nb is its operational limits in the application environment, which are closely related to material’s structure and thermodynamic stability. They are in turn closely related to the ambient (zero-pressure) melting point $\left(T_m\right);$ thus, $T_m$ is an important engineering parameter. However, the current knowledge of $T_m$ of the U-Nb system is limited, as the only experimental study of its Nb-rich portion dates back to 1958. In addition, it has not yet been adequately modeled based on general thermodynamics principles or using an equation-of-state approach. In this study, we present a theoretical model for the melting curve (liquidus) of a mixture, and apply it to U-Nb, which is considered as a mixture of pure U and pure Nb. The model uses the known melting curves of pure constituents as an input and predicts the melting curve of their mixture. It has only one free parameter, which must be determined independently. The ambient liquidus of U-Nb predicted by the model appears to be in good agreement with the available experimental data. We calculate the melting curve (the pressure dependence of $T_m$) of pure U using ab initio quantum molecular dynamics (QMD), the knowledge of which is required for obtaining the model parameters for U. We also generalize the new model to nonzero pressure and consider the melting curve of U-6 wt.% Nb (U-6Nb) alloy as an example. The melting curve of U-6Nb alloy predicted by the model appears to be in good agreement with the ab initio melting curve obtained from our QMD simulations. We suggest that the U-18Nb alloy can be considered as a proxy for protactinium (Pa) and demonstrate that the melting curves of U-18Nb and Pa are in good agreement with each other. Full article

Klebsiella oxytoca bacilli co-form the human intestinal microbiota, but in favorable conditions, they may also affect immunocompromised individuals, causing urinary tract infections, bacteremia, or antibiotic-associated hemorrhagic colitis. The growing numbers of clinical outbreaks of K. oxytoca infections make these bacteria an emerging pathogen, which is still masked by the predominant K. pneumoniae isolates. Thus, it is very important to advance knowledge on K. oxytoca pathogenicity. This work aims to characterize a urine isolate, K. oxytoca 0.062, from central Poland, which appears to present a multidrug-resistant and extended-spectrum β-lactamases-positive phenotype. The structural experiments include sugar and methylation analyses, mass spectrometry, and ¹H and ¹³C Nuclear Magnetic Resonance (NMR) spectroscopy. Additionally, ¹H,¹H ROESY, and ¹H,¹³C HMBC experiments were carried out on the high-molecular-weight O polysaccharide fraction of K. oxytoca lipopolysaccharides (LPSs). These analyses led to the detection of two polysaccharide antigens: one neutral, containing a linear trisaccharide unit called mannan, and one acidic, which is built up of a branched tetrasaccharide unit containing two mannopyranose (α-Manp) residues, one galactopyranose (β-Galp) residue, and one galacturonic acid (α-GalpA) residue. The GalpA residue seems to be a potential minor epitope, recognized by the selected Proteus antisera in the serological studies. Full article

The cooling water intake systems of coastal nuclear power plants are frequently clogged by marine organisms in the water intake area. This study uses hydroacoustic (BioSonics DT-X, 199 kHz) and trawling methods (20 mm codend mesh size) to research fish spatiotemporal dynamics. Species composition, seasonal variations in fish abundance, and target strength were analyzed. Pearson’s correlation analysis revealed a significant negative correlation between water depth and resource density. Significant differences in fish abundance and biomass density were observed among seasons and stations. An analysis of dominant species showed that the IRI (index of relative importance) of Collichthys lucidus was highest in February 2023 (5736.54), while Harpadon nehereus had the highest IRI in November 2023 (2309.17). The distribution and abundance estimates of dominant species from acoustic surveys and biological trawling were highly consistent, demonstrating the applicability and reliability of hydroacoustic methods in fish resource assessments. Through the identification of dominant species as well as the distribution patterns of fish within the water intake area, valuable data support can be provided for the confirmation of those organisms that are prone to clogging the cooling water source. Moreover, it lays a solid foundation for the development of relevant protection work. Full article

Due to increasing human engineering activities in cold regions, the precise measurement of frozen soil’s physical property parameters has become particularly important. Traditional measurements of thermal conductivity and unfrozen water content of frozen soil are usually tested separately, leading to errors in accurately understanding the dynamic variation law of permafrost’s hydrothermal parameters in the near-phase transition zone. To address this, a multi-sensor fusion technology–thermo time domain reflectometry (thermo-TDR) sensor was designed and optimized for measuring the unfrozen water content and thermal conductivity of frozen soil. Three-dimensional thermal and electromagnetic numerical models were developed to analyze and validate the design parameters of the proposed sensor. Furthermore, a corresponding validation experiment was carried out to confirm the usability and accuracy of the designed sensor. The results show that (1) under the optimized probe parameters, the deviation between the theoretical thermal conductivity and the numerical preset value is 2.94%, verifying the accuracy of the sensor in thermal physical testing. (2) With a 10 mm probe spacing design, the test area of the thermo-TDR significantly increased, and the skin effect coefficient reached 25.54%, satisfying the electromagnetic design requirements of the TDR method. (3) The designed thermo-TDR sensor realizes the simultaneous measurement of unfrozen water and thermal conductivity of frozen soil, and the experimental results present a good consistency with that of the nuclear magnetic resonance (NMR) and transient planar heat source methods. (4) Additionally, due to the drastic changes in the soil’s physical properties due to the probe’s heating process, testing errors of the thermo-TDR sensor will significantly increase in the near-phase transition range, especially in the range of −2~−1 °C. Full article

Background: The clinical relevance of circulating cell-free DNA (cfDNA) in oncology has gained significant attention, with its potential as a biomarker for cancer diagnosis and monitoring. However, its precise role in cancer biology and progression remains unclear. cfDNA in cancer patients’ blood has been shown to activate signaling pathways, such as those mediated by toll-like receptors (TLRs), suggesting its involvement in cancer cell adaptation to the tumor microenvironment. Methods: This impact of cfDNA released from MDA-MB-231, a triple-negative breast cancer (TNBC) cell line was assessed, focusing on glucose availability and culture duration. The impact of cfDNA on the proliferation of MDA-MB-231 cells was investigated using proliferation curves, while cellular migration was evaluated through wound healing assays. The metabolic alterations induced by distinct cfDNA variants in MDA-MB-231 cells were investigated through nuclear magnetic resonance (NMR) spectroscopy, and their effect on cisplatin resistance was evaluated using flow cytometry. Furthermore, the expression levels of DNA-sensitive Toll-like receptor 9 (TLR9) were quantified via immunofluorescence, alongside its colocalization with lysosome-associated membrane protein 1 (LAMP1). Results: This study indicates that cfDNA facilitates metabolic adaptation, particularly under metabolic stress, by modulating glucose and glutamine consumption, key pathways in tumor cell metabolism. Exposure to cfDNA induced distinct metabolic shifts, favoring energy production through oxidative phosphorylation. The anti-cancer activity of cfDNA isolated from conditioned media of cells cultured under stressful conditions is influenced by the culture duration, emphasizing the importance of adaptation and se-lection in releasing cfDNA that can drive pro-tumoral processes. Additionally, cfDNA exposure influenced cell proliferation, quiescence, and migration, processes linked to metastasis and treatment resistance. These findings underscore cfDNA as a key mediator of metabolic reprogramming and adaptive responses in cancer cells, contributing to tumor progression and therapy resistance. Furthermore, the activation of TLR9 signaling suggests a mechanistic basis for cfDNA-induced phenotypic changes. Conclusions: Overall, cfDNA serves as a crucial signaling molecule in the tumor microenvironment, orchestrating adaptive processes that enhance cancer cell survival and progression. Full article

This study examines how economic growth, travel, global connection, and changes in population impact the environmental footprint in seven countries, including Russia, the US, China, France, the UK, Pakistan, and India, from 1995 to 2023. The results show a significant link between Granger’s environmental impact and some economic, non-economic, and population factors in these countries. According to the study, environmental impacts result primarily from economic expansion and tourism revenue generation. The essential activities in economic development frequently result in significant ecological deficits through natural resource depletion, land alterations, and environmental releases. Business enlargement and tourism income commonly bring about deforestation while causing both pollution and habitat damage, thus showing why sustainable practices must exist to protect nature during economic development. We also have to consider factors other than economics, such as total income from natural resources and using nuclear power early. Additionally, how many people live in a particular area and the number of children born contribute to these footprints. Also, this study shows how economic, non-economic and demographic issues can indicate what harm the environment might face later. This is especially important in countries that use nuclear energy extensively. The report suggests different ways to solve this problem. These include advocating for sustainable tourism practices, directing research efforts towards nuclear energy, supporting renewable energy initiatives, promoting family planning and education, and raising public awareness. The aim is to reduce the environmental harm caused by nuclear energy and promote a more sustainable future. Full article

With the transformation of the world’s energy structure and the promotion of clean energy, nuclear power has come to the fore as an efficient and environmentally friendly form of energy. As critical components in the operation of nuclear power plants (NPPs), suction and transportation devices for thermal traps—designed to prevent and control floating bodies—are directly linked to the safety of power generation, the stability of operations, and the reliability of the power grid in NPPs. Technical research and advancements in these devices play a crucial role in enhancing their effectiveness. In view of the intrusion and blockage of floating bodies in the sewage network pocket of the water intake with the cold-source system for coastal NPPs, the key technologies to prevent and control floating bodies that may impair cooling resources in NPPs’ thermal traps is discussed. This paper introduces the safety risks and social impacts associated with water intake, highlights the importance of the water-intake system, and discusses the interception and transportation mechanisms in NPPs. The progress of explosive floating bodies’ interception, cleaning, suction, transportation, and intelligent monitoring technology is introduced through the technical progress in the types of floating bodies, as well as cutting, crushing, suction, and transportation devices. The technical progress of efficient treatment is realized, which provides reference for the research and practice of the key technologies for suction and transportation devices to prevent and control floating bodies’ suction and transportation devices in NPPs’ thermal traps. Full article