A native fungal symbiont facilitates the prevalence and development of an invasive pathogen-native vector symbiosis

Invasive pathogen–insect symbioses have been extensively studied in many different ecological niches. Whether the damage of symbioses in different introduced regions might be influenced by other microorganisms has, however, received little attention. Eight years of field data showed that the varied levels of the nematode and beetle populations and infested trees of the invasive Bursaphelenchus xylophilus–Monochamus alternatus symbiosis were correlated with patterns in the isolation frequencies of ophiostomatoid fungi at six sites, while the laboratory experiments showed that the nematode produced greater numbers of offspring with a female-biased sex ratio and developed faster in the presence of one native symbiotic ophiostomatoid fungus, Sporothrix sp. 1. Diacetone alcohol (DAA) from xylem inoculated with Sporothrix sp. 1 induced B. xylophilus to produce greater numbers of offspring. Its presence also significantly increased the growth and survival rate of M. alternatus, and possibly explains the prevalence of the nematode–vector symbiosis when Sporothrix sp. 1 was dominant in the fungal communities. Studying the means by which multispecies interactions contributed to biogeographical dynamics allowed us to better understand the varied levels of damage caused by biological invasion across the invaded range.The National Basic Science Research Program (2009CB119204 and 2012CB114105), National Natural Science Foundation of China (31272323, 31221091, 31370650, and 30970369), the CAS Knowledge Innovation Key Research Program (KSCX2-EW-J-2), and the European Seventh Framework Project REPHRAME.http://www.esajournals.org/loi/ecol?am201

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

Role of Human-Mediated Dispersal in the Spread of the Pinewood Nematode in China

Background: Intensification of world trade is responsible for an increase in the number of alien species introductions. Human-mediated dispersal promotes not only introductions but also expansion of the species distribution via long-distance dispersal. Thus, understanding the role of anthropogenic pathways in the spread of invading species has become one of the most important challenges nowadays. Methodology/Principal Findings: We analysed the invasion pattern of the pinewood nematode in China based on invasion data from 1982 to 2005 and monitoring data on 7 locations over 15 years. Short distance spread mediated by long-horned beetles was estimated at 7.5 km per year. Infested sites located further away represented more than 90% of observations and the mean long distance spread was estimated at 111–339 km. Railways, river ports, and lakes had significant effects on the spread pattern. Human population density levels explained 87% of the variation in the invasion probability (P,0.05).Since 2001, the number of new records of the nematode was multiplied by a factor of 5 and the spread distance by a factor of 2. We combined a diffusion model to describe the short distance spread with a stochastic,individual based model to describe the long distance jumps. This combined model generated an error of only 13% when used to predict the presence of the nematode. Under two climate scenarios (stable climate or moderate warming), projections of the invasion probability suggest that this pest could expand its distribution 40–55% by 2025. Conclusions/Significance: This study provides evidence that human-induced dispersal plays a fundamental role in the spread of the pinewood nematode, and appropriate control measures should be taken to stop or slow its expansion. This model can be applied to Europe, where the nematode had been introduced later, and is currently expanding its distribution. Similar models could also be derived for other species that could be accidentally transported by humans

Lysine-mediated hydroxyethyl starch-10-hydroxy camptothecin micelles for the treatment of liver cancer

Liver cancer is a malignant tumor with extremely high morbidity and mortality. At present, traditional chemotherapy is still the most commonly used therapeutic approach. However, serious side effects lead to the treatment of liver cancer is not ideal. Therefore, it is imperative to develop a new drug delivery system based on nanotechnology and liver cancer microenvironment. In this study, a pH/reduction/α-amylase multi-sensitive hydroxyethyl starch-10-hydroxy camptothecin micelles (HES-10-HCPT-SS-Ly) targeting over-expressed amino acid (AA) transporters on the surface of liver cancer cell by applying lysine were successfully synthesized. The prepared micelles showed regular structure, suitable particle size, and intelligent drug release property. Compared with conventional HES-10-HCPT micelles and 10-HCPT injection, HES-10-HCPT-SS-Ly micelles demonstrated better in vitro anti-proliferative capability toward human liver cancer Hep-G2 cells and greater antitumor efficiency against nude mouse with Hep-G2 tumor. These findings suggest that HES-10-HCPT-SS-Ly micelles may be a promising nanomedicine for treatment of liver cancer

Semantic-Structure-Aware Multi-Level Information Fusion for Robust Global Orientation Optimization of Autonomous Mobile Robots

Multi-camera-based simultaneous localization and mapping (SLAM) has been widely applied in various mobile robots under uncertain or unknown environments to accomplish tasks autonomously. However, the conventional purely data-driven feature extraction methods cannot utilize the rich semantic information in the environment, which leads to the performance of the SLAM system being susceptible to various interferences. In this work, we present a semantic-aware multi-level information fusion scheme for robust global orientation estimation. Specifically, a visual semantic perception system based on the synthesized surround view image is proposed for the multi-eye surround vision system widely used in mobile robots, which is used to obtain the visual semantic information required for SLAM tasks. The original multi-eye image was first transformed to the synthesized surround view image, and the passable space was extracted with the help of the semantic segmentation network model as a mask for feature extraction; moreover, the hybrid edge information was extracted to effectively eliminate the distorted edges by further using the distortion characteristics of the reverse perspective projection process. Then, the hybrid semantic information was used for robust global orientation estimation; thus, better localization performance was obtained. The experiments on an intelligent vehicle, which was used for automated valet parking both in indoor and outdoor scenes, showed that the proposed hybrid multi-level information fusion method achieved at least a 10-percent improvement in comparison with other edge segmentation methods, the average orientation estimation error being between 1 and 2 degrees, much smaller than other methods, and the trajectory drift value of the proposed method was much smaller than that of other methods

Quantification of the Adjacency Effect on Measurements in the Thermal Infrared Region

International audienceSensor-observed energy from adjacent pixels, known as the adjacency effect, influences land surface reflectivity retrieval accuracy in optical remote sensing. As the spatial resolution of thermal infrared (TIR) images increases, the adjacency effect may influence land surface temperature (LST) retrieval accuracy in TIR remote sensing. However, to our knowledge, few studies have focused on quantifying this adjacency effect on TIR measurements. In this study, a forward adjacency effect radiative transfer model (FAERTM) was developed to quantify the adjacency effect on high-spatial-resolution TIR measurements. The model was verified to be in good agreement with moderate resolution atmospheric transmission (MODTRAN) code, with a discrepancy 3 K in some cases. These findings indicate that the adjacency effect should be considered when retrieving LSTs from TIR measurements, at least in some specific conditions. The proposed FAERTM provides a useful model for quantifying and addressing the adjacency effect on TIR measurements

Synthesis and properties of transparent polyimides derived from trans-1,4-bis(2,3-dicarboxyphenoxy)cyclohexane dianhydride

A series of transparent polyimides was prepared from trans-1,4-bis(2,3-dicarboxyphenoxy)cyclohexane dianhydride (trans-3,3'-CHDPA) with various aromatic diamines via one-step solution polycondensation. The glass transition temperatures (T(g)s) of the resulting polyimides were in the range of 206-255 degrees C. These polyimide films showed high optical transparency with cut-off wavelengths of 370-379 nm, and they exhibited good mechanical properties with tensile strengths of 65-88 MPa, tensile moduli of 1.7-2.4 GPa, and elongations at break of 4.7-7.5%. Compared with polyimides based on trans-1,4-bis(3,4-dicarboxyphenoxy)cyclohexane dianhydride (trans-4,4'-CHDPA), the polyimides derived from trans-3,3'-CHDPA showed higher T-g, better solubility and optical transparency due to the 3- and 4-position isomeric effect

Effect of Pressure and Temperature on CO2/CH4 Competitive Adsorption on Kaolinite by Monte Carlo Simulations

The adsorption of CO2 and CO2/CH4 mixtures on kaolinite was calculated by grand canonical Monte Carlo (GCMC) simulations with different temperatures (283.15, 293.15, and 313.15 K) up to 40 MPa. The simulation results show that the adsorption amount of CO2 followed the Langmuir model and decreased with an increasing temperature. The excess adsorption of CO2 increased with an increasing pressure until the pressure reached 3 MPa and then decreased at different temperatures. The S C O 2 / C H 4 decreased logarithmically with increasing pressure, and the S C O 2 / C H 4 was lower with a higher temperature at the same pressure. The interaction energy between CO2 and kaolinite was much higher than that between CH4 and kaolinite at the same pressure. The interaction energy between the adsorbent and adsorbate was dominant, and that between CO2 and CO2 and between CH4 and CH4 accounted for less than 20% of the total interaction energy. The isothermal adsorption heat of CO2 was higher than that of CH4, indicating that the affinity of kaolinite to CO2 was higher than that of CH4. The strong adsorption sites of carbon dioxide on kaolinite were hydrogen, oxygen, and silicon atoms, respectively. CO2 was not only physically adsorbed on kaolinite, but also exhibited chemical adsorption. In gas-bearing reservoirs, a CO2 injection to displace CH4 and enhance CO2 sequestration and enhanced gas recovery (CS-EGR) should be implemented at a low temperature