Multispectroscopic and Computational Study of the Interaction between α-Cembrenediol and Bovine Serum Albumin

α-Cembrenediol displays a diverse array of biological activities, encompassing antibacterial, antitumor, and neuroprotective effects. To comprehensively understand the in vivo transport, distribution, and elimination mechanisms associated with α-cembrenediol, its interaction with bovine serum albumin (BSA) was investigated. In this study, the interaction between α-cembrenediol and BSA was explored using various techniques, including UV absorption, steady-state fluorescence, circular dichroism spectrum, molecular docking, and molecular dynamics simulation. The results showed that there was a clear interaction between BSA and α-cembrenediol. Specifically, the KSV and Kb decreased with increasing temperature at 293, 303, and 310 K, indicating that α-cembrenediol interacted with BSA through a static quenching mechanism. Furthermore, the number of binding sites was approximately 1 at the three temperatures, suggesting the presence of a single specific binding site for α-cembrenediol on BSA. Moreover, the binding process occurred spontaneously (ΔG<0), primarily driven by hydrogen bonds and van der Waals forces (ΔH<0 and ΔS<0). α-Cembrenediol bound to the Sudlow site I of BSA. Binding of BSA to α-cembrenediol also caused its conformation to change. This study provides essential insights into the interaction between α-cembrenediol and BSA, contributing to a better understanding of the pharmacokinetic properties of the compound

Direct and indirect effects of climate on richness drive the latitudinal diversity gradient in forest trees

Data accessibility statement: Full census data are available upon reasonable request from the ForestGEO data portal, http://ctfs.si.edu/datarequest/ We thank Margie Mayfield, three anonymous reviewers and Jacob Weiner for constructive comments on the manuscript. This study was financially supported by the National Key R&D Program of China (2017YFC0506100), the National Natural Science Foundation of China (31622014 and 31570426), and the Fundamental Research Funds for the Central Universities (17lgzd24) to CC. XW was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB3103). DS was supported by the Czech Science Foundation (grant no. 16-26369S). Yves Rosseel provided us valuable suggestions on using the lavaan package conducting SEM analyses. Funding and citation information for each forest plot is available in the Supplementary Information Text 1.Peer reviewedPostprin

Interactions between all pairs of neighboring trees in 16 forests worldwide reveal details of unique ecological processes in each forest, and provide windows into their evolutionary histories

When Darwin visited the Galapagos archipelago, he observed that, in spite of the islands’ physical similarity, members of species that had dispersed to them recently were beginning to diverge from each other. He postulated that these divergences must have resulted primarily from interactions with sets of other species that had also diverged across these otherwise similar islands. By extrapolation, if Darwin is correct, such complex interactions must be driving species divergences across all ecosystems. However, many current general ecological theories that predict observed distributions of species in ecosystems do not take the details of between-species interactions into account. Here we quantify, in sixteen forest diversity plots (FDPs) worldwide, highly significant negative density-dependent (NDD) components of both conspecific and heterospecific between-tree interactions that affect the trees’ distributions, growth, recruitment, and mortality. These interactions decline smoothly in significance with increasing physical distance between trees. They also tend to decline in significance with increasing phylogenetic distance between the trees, but each FDP exhibits its own unique pattern of exceptions to this overall decline. Unique patterns of between-species interactions in ecosystems, of the general type that Darwin postulated, are likely to have contributed to the exceptions. We test the power of our null-model method by using a deliberately modified data set, and show that the method easily identifies the modifications. We examine how some of the exceptions, at the Wind River (USA) FDP, reveal new details of a known allelopathic effect of one of the Wind River gymnosperm species. Finally, we explore how similar analyses can be used to investigate details of many types of interactions in these complex ecosystems, and can provide clues to the evolution of these interactions

Comparison and analysis of ground seed detectors and interpolation methods in airborne LiDAR filtering

Ground seed detectors and interpolation methods are fundamental components of filtering algorithms. However, the performance of different detectors and interpolation methods typically varies, and few studies have been conducted on the adaptability of different detectors and interpolation methods to different terrains. Therefore, we compare three ground seed detectors (cylindrical neighborhood (CN), fixed grid (FG), and moving window (MW)) and three interpolation methods (triangulated irregular network (TIN), thin plate spline (TPS), and inverse distance weighting (IDW)). In addition, nine filters are constructed by combining the three ground seed detectors and the three interpolation methods to evaluate their comprehensive influences. To assess the performance of these detectors, interpolation methods, and filters, fifteen ISPRS-supplied light detection and ranging (LiDAR) benchmark datasets are utilized in the experiment. The findings indicate that the CN-TPS filter, which combines the CN detector and TPS method, achieves superior performance across mean Pg (99.16 % – correctly classified ground points divided by all extracted ground points), RMSE (0.44 m – root mean squared error), and total error (3.78 %). Moreover, the filtering methods are mainly affected by the performance of the ground seed detector and are less affected by the selected interpolation method. These results can be used to provide a valuable reference for designing an optimal LiDAR filtering algorithm for varied terrain types and applications

Sealed Wave Power Generator

AbstractThe design of a sealed wave power generator has been proposed, whose driving parts are sealed in a closed outer covering to protect them from corrosion by sea water. Wave energy is collected using a pendulum. Overrunning roller clutches are used to convert the swing of the pendulum to unidirectional rotation of generators. A design method based on the Principle of Conservation of Energy has been proposed. A guide plate is equipped on the platform where the wave power generator sits on, to ensure the swing plane of the pendulum parallel to the main vibration plane of the wave. Power processing circuit has also been equipped, which can perform automatic current and voltage regulation under the condition of large variation of wave height and cycle. Experiments have demonstrated that the sealed wave power generator is applicable

Chemical Composition, and Antioxidant and Cholinesterase Inhibitory Activities of <i>Lindera glauca</i> Fruit Essential Oil and Molecular Docking Studies of Six Selected Compounds

Lindera glauca is a shrub or small tree mostly distributed in China, Japan and Korea. However, reports on the biological activities of Lindera glauca fruit essential oil (LGFEO) are limited. The study on its chemical composition, and antioxidant and cholinesterase inhibitory activities were performed, along with molecular docking of six selected compounds. The LGFEO was extracted by hydro distillation and analyzed by GC-MS and GC-FID. Antioxidant activities of LGFEO were evaluated by three methods with different mechanisms. Acetylcholinesterase and butyrylcholinesterase inhibitory activities of LGFEO were tested. A total of 48 components were identified representing 95.74% of the total composition of LGFEO in which the major compounds were (E)-β-ocimene (41.53%), α-copaene (13.17%), δ-cadinene (6.20%), 3-carene (5.89%) and eucalyptol (3.57%). Weak antioxidant activities of LGFEO in three assays (9.52, 11.36 and 38.98 μmol TE/g, respectively) were observed. LGFEO showed obvious cholinesterase inhibitory activities at the final concentrations of 50 and 20 μg/mL. IC50 values for acetylcholinesterase and butyrylcholinesterase were 46.48 and 34.85 μg/mL, respectively. Molecular docking revealed that geranyl acetate, β-caryophyllene and limonene had lower binding affinities in the range of −7.1 to −6.1 kcal/mol through hydrophobic interactions and hydrogen bond. Six compounds including 3-carene, limonene, eucalyptol, (E)-β-ocimene, geranyl acetate and β-caryophyllene could contribute together to cholinesterase inhibitory activities of LGFEO. This essential oil indicated low potential as natural antioxidant, but it could be potentially used as cholinesterase inhibitor with possible application in food, aromatherapy and pharmaceutical industries

High-Efficiency Utilization of Waste Tobacco Stems to Synthesize Novel Biomass-Based Carbon Dots for Precise Detection of Tetracycline Antibiotic Residues

Recycling waste biomass into valuable products (e.g., nanomaterials) is of considerable theoretical and practical significance to achieve future sustainable development. Here, we propose a one-pot hydrothermal synthesis route to convert waste tobacco stems into biomass-based N, S-codoped carbon dots (C&minus;dots) with the assistance of carbon black. Unlike most of the previously reported luminescent C&minus;dots, these biomass-based C&minus;dots showed a satisfactory stability, as well as an excitation-independent fluorescence emission at ~520 nm. Furthermore, they demonstrated a pH-dependent fluorescence emission ability, offering a scaffold to design pH-responsive assays. Moreover, these as-synthesized biomass-based C&minus;dots exhibited a fluorescence response ability toward tetracycline antibiotics (TCs, e.g., TC, CTC, and OTC) through the inner filter effect (IFE), thereby allowing for the establishment a smart analytical platform to sensitively and selectively monitor residual TCs in real environmental water samples. In this study, we explored the conversion of waste tobacco stems into sustainable biomass-based C&minus;dots to develop simple, efficient, label-free, reliable, low-cost, and eco-friendly analytical platforms for environmental pollution traceability analysis, which might provide a novel insight to resolve the ecological and environmental issues derived from waste tobacco stems

Improving the Synthesis Efficiency of Amino Acids by Analyzing the Key Sites of Intracellular Self-Assembly of Artificial Cellulosome

To explore the key sites affecting the intracellular assembly of key components of cellulosomes and obtain DocA mutants independent of Ca2+, Swiss-model, GROMACS, PyMOL, and other molecular dynamics simulation software were used for modeling and static and dynamic combination analysis. Site-specific mutation technology was used to mutate DocA, and Biacore was used to test the dependence of Ca2+ on the binding ability of protein DocA mutants and protein Coh, and to analyze the interaction and binding effect of mutant proteins in vitro. Forward intracellular mutant screening was performed based on semi-rational design and high throughput screening techniques. The orientation of mutations suitable for intracellular assembly was determined, and three directional mutant proteins, DocA-S1, DocA-S2, and DocA-S3, were obtained. Ca2+ independent DocA mutants were obtained gradually and their potential interaction mechanisms were analyzed. In the present study, intracellular self-assembly of key components of cellulosomes independent of Ca2+ was achieved, and DocA-S3 was applied to the assembly of key enzymes of L-lysine biosynthesis, in which DapA and DapB intracellular assembly increased L-lysine accumulation by 29.8% when compared with the control strains, providing a new strategy for improving the intracellular self-assembly of cellulosomes and amino acid fermentation efficiency

Inhibition of furin by bone targeting superparamagnetic iron oxide nanoparticles alleviated breast cancer bone metastasis

Breast cancer bone metastasis poses significant challenge for therapeutic strategies. Inside the metastatic environment, osteoclasts and tumor cells interact synergistically to promote cancer progression. In this study, the proprotein convertase furin is targeted due to its critical roles in both tumor cell invasion and osteoclast function. Importantly, the furin inhibitor is specifically delivered by bone targeting superparamagnetic iron oxide (SPIO) nanoparticles. Our in vitro and in vivo data demonstrate that this system can effectively inhibit both osteoclastic bone resorption and breast cancer invastion, leading to alleviated osteolysis. Therefore, the bone targeting &amp; furin inhibition nanoparticle system is a promising therapeutic and diagnostic strategy for breast cancer bone metastasis