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The unique properties of metal-organic frameworks (MOFs) such as their large surface area and high porosity have attracted considerable attention in recent decades. The MOFs are a promising class of materials for developing highly efficient biosensors due to these same properties. This bibliometric analysis focused on the use of MOFs as enzyme-coupled materials in biosensor construction and aimed to provide a comprehensive overview of the research field by analyzing a collected database. The analysis included identifying the countries that have published the most, the most prominent applications, and trends for future directions in the field. The study used three databases with different numbers of documents, differentiated by research areas, with refinements made to the search as needed. The results suggest that MOF-derived biosensors are a growing field, with the Republic of China emerging as a significant contributor to research in this area. The study also used computational processing of trend analysis and geocoding to reveal these findings.

Biodiesel can be produced from vegetable oils, animal fats, frying oils, and from microorganism-synthesized oils. These sources render biodiesel an easily biodegradable fuel. The aim of this work was to perform an advanced bibliometric analysis of primary studies relating to biodiesel production worldwide by identifying the key countries and regions that have shown a strong engagement in this area, and by understanding the dynamics of their collaboration and research outputs. Additionally, an assessment of the main primary feedstocks employed in this research was carried out, along with an analysis of the current and future trends that are expected to define new paths and methodologies to be used in the manufacture of biodegradable and renewable fuels. A total of 4586 academic outputs were selected, including peer-reviewed research articles, conference papers, and literature reviews related to biodiesel production, in the time period spanning from 2010 to 2021. Articles that focused on feedstocks for the production of biodiesel were also included, with a search that returned 330 papers. Lastly, 60 articles relating to biodiesel production via sewage were specifically included to allow for an analysis of this source as a promising feedstock in the future of the biofuel market. Via the geocoding and the document analyses performed, we concluded that China, Malaysia, and India are the largest writers of articles in this area, revealing a great interest in biofuels in Asia. Additionally, it was noted that environmental concerns have caused authors to conduct research on feedstocks that can address the sustainability challenges in the production of biodiesel.

Daemonorops (Indonesian: jernang) resin is one of Indonesia’s leading non-timber forest products and can be developed as a source of natural antioxidants and sun protection. This study aimed to select promising solvents for extracting a Daemonorops acehensis resin and phytosome formulation with high antioxidant capacities and sun protection factor (SPF) values. Jernang resin was extracted using a water–ethanol mixture in five different ratios. The promising extract was then mixed with soy lecithin in three different formulations. A promising extract and phytosome were then selected based on their antioxidant capacities and sun protection factor (SPF) values. A liquid chromatography mass spectrometry/mass spectrometry (LC–MS/MS) analysis was also performed on five extracts to identify the components in the extracts that might be responsible for the biological activity. The results showed that the ethanol solvent variation and phytosome formulation influenced the antioxidant capacity and SPF value. A hundred-percent ethanolic extract and F1 phytosome exhibited the highest antioxidant capacities and SPF values. A qualitative analysis revealed the various classes of compounds in the extract and phytosome. A flavylium chromophore, dracorhodin, dominated the resin extract and was presumed to be the marker compound responsible for their antioxidant capabilities and SPF values. These findings are important for manufacturing sunscreens containing active compounds of bioactive natural resins.

Reactive oxygen species (ROS) are related to several degenerative diseases. In this study, Acacia, a genus with many fast-growing species, was investigated to explore the many phytochemical compounds that are biologically active in processes dealing with ROS-related diseases. This study aimed to select extracts of Acacia heartwood on the basis of their pharmacological and phytochemical profiles and identify their bioactive compounds. Five methanolic extracts from Acacia heartwood were evaluated for their antioxidant activity using three different in vitro assays: toxicity toward Artemia salina and phenolic and polyphenolic content. Multivariate analysis was conducted to select two promising extracts and then their bioactive compounds were identified using liquid chromatography coupled with mass spectrometry. Acacia crassicarpa extracts showed the highest antioxidant activity, as well as phenolic and hydrolyzable tannin contents, but low toxicity. The A. mangium extract exhibited high flavonoid and condensed tannin content, whereas A. decurrrens had the highest toxicity with low antioxidant activity. Pearson’s correlation analysis demonstrated no correlation between antioxidant activity and toxicity. Moreover, the phytochemical profile exhibited an association with pharmacological parameters. Principal component analysis followed by cluster analysis divided the extracts into three clusters. Two heartwood extracts of A. crassicarpa and A. auriculiformis were chosen as the best extracts. Identification showed that these extracts were dominated by phenolic compounds, as well as anthraquinone and xanthone.

Real-life stressors, such as university examination, cause an increase in sympathetic activity of the nervous system innervating the heart, and thus an increase in heart rate (HR). Our study aimed to detect changes in heart rate variability (HRV) during different stages of an exam in a group of 90 healthy university students (30 males and 60 females), over 4 h of monitoring divided into 1 h before, 2 h during, and 1 h after the examination. HRV was significantly highest after the exam, indicating release from stress, as compared to before and during the examination when stress was observable. Undergraduate students in different academic years did not differ in terms of stress, indicating the absence of adaptation to exam procedures. However, HR and R-R interval after the exam showed significant difference between first year undergraduate studies and first year of a graduate program, indicating a higher degree of confidence in graduate students. Results also suggest that HRV in females is significantly lower than that in males before and after examination, despite men having greater sympathetic input. In conclusion, the results of our novel study assessing stress in real-time examination show important gender differences, and lack of adaptation with academic study year.