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First record of Xiphydria prolongata (Geoffroy, 1785) (Hymenoptera: Xiphydriidae) in Greece
No full textXiphydria prolongata (Geoffroy, 1785) is reported in Greece for the first time, from a mixed riparian forest in the northeastern Peloponnese. The species’ distribution, ecology, and the characteristics of the collection site are briefly discussed and documented with habitat and specimen photographs
Bryophyte flora of two peculiar sites in the Mt. Papuk (Eastern Croatia)
No full textDuring ongoing bryological surveys conducted in the Mt. Papuk, two significant sites, Sokolina Gosted and Svinjarevac, have been identified. These sites are characterized by unique acidophilic forests with a predominance of peat mosses on the forest floor. Sokolina Gosted represents the first documented locality in Croatia for four taxa: Andreaea rothii ssp. rothii, Grimmia donniana, G. montana, and Racomitrium affine. Furthermore, Buxbaumia aphylla and Dicranum spurium were observed for the first time at both Sokolina Gosted and Svinjarevac. Additionally, several extremely rare species have been reported at one or both locations, including Cynodontium polycarpon, Dicranum polysetum, Isopaches bicrenatus, Jungermannia pumila, Pleuridium acuminatum, Rhabdoweisia fugax, Syzygiella autumnalis and Ulota intermedia. Consequently, both locations serve as important bryological hotspots, exhibiting distinctive species assemblages within unique habitats relevant to Southeast Europe. While the significance of these sites in terms of bryophyte diversity is clear, the presence of the invasive species Campylopus introflexus underscores the necessity for ongoing research and monitoring efforts in the area
Greening Hotel Brand Experience in the Era of Experience-Seeking Customers: A Managerial Perspective
No full textThe research note elaborates on the role of green marketing in creating the hotel brand experience (HBE). It aims to reduce the gap in understanding how hotel brand managers stage green encounters within the brand experience and what they believe drives negative vs. positive guest experiences when exposed to specific green marketing initiatives. The theoretical background is followed by the presentation of results from qualitative research conducted with managers in Croatia's leading four- and five-star hotel chains and standalone hotels. Hotel managers consider green marketing a crucial driver for success and long-term survival. Despite a shared belief that delivering a superior experience is a priority, green initiatives are often chosen primarily on the basis of implementation costs. Encounters in which guests are presented with higher investments by the hotel lead to more positive brand experiences. Although hotel managers believe that affective experiences are the most important, they are particularly interested in evoking cognitive experiences through green marketing messages. Therefore, further research should focus on identifying ways to evoke an affective brand experience
Glucose-mixotrophic culture of the freshwater alga Chlorella vulgaris alleviates the phytotoxicity of silver nanoparticles
No full textSilver nanoparticles (AgNPs) are widely used due to their specific physico-chemical properties, but their release in wastewater poses a threat to aquatic ecosystems. The microalga Chlorella vulgaris is often used as a model organism in toxicological research. Since this alga can switch from an autotrophic to a mixotrophic mode of life, we investigated whether glucose as an additional energy source can mitigate AgNP phytotoxic effects. Algae were cultivated in a nutrient medium with and without glucose and treated with a concentration of AgNPs allowing 60% cell survival. The effects were studied by monitoring oxidative stress and photosynthesis parameters. In the absence of glucose, AgNPs caused significant accumulation of reactive oxygen species, increased lipid peroxidation and carotenoid content with weak activation of antioxidant enzymes. In addition, reduced photosynthetic efficiency and ultrastructural damage were observed. The addition of glucose to AgNP treatments attenuated all negative effects by reducing oxidative stress and increasing the activity of antioxidant enzymes. Furthermore, C. vulgaris cells exposed in glucose-enriched media showed recovered photosynthesis by exhibiting the photosynthetic rate and chlorophyll fluorescence parameters of control algae. Ultrastructural analysis showed greater synthesis of lipid droplets and less structural damage. The study shows that glucose supplementation effectively mitigates the phytotoxic effects of AgNPs on C. vulgaris. By reducing oxidative stress, enhancing antioxidant enzyme activity and restoring photosynthetic function, glucose helps maintain cellular integrity and overall algal health in the presence of AgNPs, which suggests that mixotrophic cultivation may represent a protective strategy against nanoparticle-induced toxicity in aquatic microalgae
Questionnaire on reproductive control as a component of preventive medicine in the dog and cat population in Portugal
No full textPreventive veterinary medicine is an integral part of health care in veterinary practice and hospitals. Its primary objectives are to reduce the risk of developing pathologies, improve animal wellbeing and promote their long-term health. This field encompasses various areas, including reproductive medicine. The presented study aimed to analyse the knowledge, attitudes and perceptions of a sample of the Portuguese population regarding preventive veterinary medicine and its related domains, as well as the significance attributed to it. An online questionnaire disseminated through social media platforms was used for data collection. The sample consisted of 100 adult respondents. The results indicated that the majority of participants possessed a good level of knowledge and demonstrated appropriate attitudes and practices concerning preventive veterinary medicine, particularly with respect to reproductive control. Notably, 72% of participants reported having their animals spayed or neutered, with 41.2% of female dogs sterilised before their first oestrous cycle. Furthermore, a significant portion of respondents accurately identified the advantages and potential complications associated with sterilisation. Additionally, this study highlighted certain educational gaps, suggesting the need for more focused and effective education for pet owners, in which the veterinary team plays a pivotal role
Lactate and pyruvate concentrations and their ratios as a marker for local or systemic hypoxic-ischaemic injury
No full textLactate and pyruvate play a crucial role in assessing the metabolic status of critically ill patients. Under normal conditions, lactate is produced by anaerobic glycolysis and is excreted by the liver and kidneys. Elevated lactate levels, referred to as hyperlactatemia, can be caused by various conditions, including tissue hypoxia, impaired oxygen utilisation, and metabolic disorders. Hyperlactatemia is often associated with adverse outcomes, particularly in critical illnesses such as sepsis and shock. Lactic acidosis, characterised by both elevated lactate levels and decreased blood pH, further exacerbates metabolic acidosis and leads to multi-organ failure if left untreated. The lactate-to-pyruvate ratio (L/P) is a potential biomarker to differentiate between hypoxic and non-hypoxic hyperlactatemia. A high L/P ratio indicates significant mitochondrial dysfunction and impaired oxidative metabolism, which often means a poorer prognosis. Conversely, a lower L/P ratio tends to indicate a more favourable outcome. However, the clinical utility of the L/P ratio is limited by the difficulty of measuring pyruvate and its dependence on factors such as pH and redox potential. Although lactate measurements are routinely performed in the emergency department and intensive care unit, there is little data on the prognostic value of the L/P ratio. Recent studies have shown that persistent hyperlactatemia with an elevated L/P ratio during the first 24 hours of septic shock correlates with increased mortality and organ failure. In addition, research on critical conditions such as the coronavirus 2019 disease (COVID-19) suggests that circulating pyruvate levels may also predict disease severity. Overall, the L/P ratio has the potential to be a valuable tool for monitoring critically ill patients, but further research is needed to confirm its broader clinical applicability
Research on the Prediction of Nano-Organic Synthesis Reaction Pathways Based on Graph Neural Networks
No full textAt present, due to the potential biological toxicity risks and economic considerations in the preparation of nanomaterials, their green synthesis and application in environmental governance have attracted much attention. However, this field still faces core challenges: the molecular mechanism of the green synthesis pathway is not yet clear, and the pollutant removal efficiency still has a significant gap compared with traditional methods. In this study, the synthesis conditions of nanometers were optimized through the graph neural network model, and an improved graph neural network algorithm based on molecular segmentation was proposed. Based on the composition mechanism of material molecules and the division of functional groups, an unsupervised learning method is constructed to segment the graph data structure composed of molecules. Combined with the structure after molecular segmentation, a new graph neural network is designed to pay more attention to the local effects of functional groups. Through experiments in databases such as solubility, the improved graph neural network has better prediction performance. Meanwhile, the combination of molecular segmentation and graph interpretation algorithms guides the graph interpretation algorithms to search for substructures containing complete functional groups. For the interpretation of structure-performance, it is more in line with the mechanism of molecular composition and has more practical significance for performance analysis and the design of new materials
Modelling of Ice-Jam Floods in the Lower Part of the Danube Basin: Case Studies During the Winters of 2011/2012 and 2016/2017
No full textThe design flood (DF) for flood defence systems for large rivers is typically determined by taking into account the maximum water levels of the year, which typically occur in Central Europe between May and June (rivers like the Danube, Tisza, and Sava). The DF is typically calculated using a 1% probability of a flood peak and an additional 0,8-1,2 meters of freeboard height. Hydraulic models have been also employed to analyze scenarios of probable maximum floods (PMF). Nevertheless, despite their substantial influence on flood processes, ice-jam floods (IJFs) are rarely taken into account. Compared to open-channel flooding, the processes controlling the formation of peak flood waves under ice-jam conditions are very different. Consequently, these processes must be incorporated into calculations for probable maximum floods due to ice jamming (PMFice). Despite recent advancements in instrumentation, modelling techniques, and laboratory research, accurately defining hydraulic parameters under ice-covered conditions still requires direct field measurements. This study utilizes published hydrometric data from gauging stations along the Serbian part of the Danube River during ice-jam events in the winters of 2011/2012 and 2016/2017. Case studies were selected on a river section identified as critical during these periods. The analyses presented in this paper indicate that the Manning roughness coefficient for the entire river channel, including the ice cover, is approximately nc ≈ 0.0186 ms-1/3, while the coefficient for the ice sheet alone is estimated at ni ≈ 0.0145 ms-1/3. Hydraulic modelling of the studied river section yielded a Manning coefficient for the main channel of n ≈ 0.0225 ms-1/3, which may pose a challenge for designers. Since air-water friction is negligible in open-channel flow conditions, the hydraulic gradient under ice-covered flow conditions can be explained by the fact that it is roughly half of that in open-channel flow (R = H/2)