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The black hole illusion (BHI) is a subtype of spatial disorientation that can result in fatal consequences in aviation. Research on the BHI has generally focused on altitude deviation, and few studies have examined the effect across different flight phases. In a simulation-based experiment, 18 participants performed 12 simulated approach and landing tasks in normal and BHI environments. Flight performance was analyzed with 14 flight parameters and was compared across five points and three phases, which were referenced from a National Transportation Safety Board report and other previous studies. Results showed that multiple flight parameters were significantly impaired and that their influences varied from the initial approach to the final touchdown. In the BHI environment, participants tended to descend aggressively during the approach phase and flew a lower but similar glidepath during the last approach phase. They might have realized the abnormal situation induced by the BHI but usually were unable to recover from the dangerous maneuver in time. Additionally, the result of glide path error, one of the most commonly used variables in previous BHI research, was only significant during the last approach phase. Flight stability was also impaired in the BHI environment. This is the first study to systematically analyze the BHI effects on multiple flight parameters at different flight phases. The use of this experimental paradigm could facilitate future research to evaluate and prevent the BHI in a more comprehensive way. • Future studies should investigate the black hole illusion with multiple flight parameters and across different phases. • Flight simulation and Bayesian statistics were utilized to assess the influences of the BHI on flight performance. • The last approach phase is more critical than the approach or landing phase in the black hole illusion environment. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus (S. aureus) infections pose a serious threat to human health worldwide. Therefore, selective and accurate detection of S. aureus is necessary for preventing infections. Herein, we design the colorimetric-electrochemical sensing platform based on specific oligonucleotide (SA31 aptamer)-tunable oxidase-like activity of mesoporous polydopamine/MnO 2 (MPDA/MnO 2) nanozymes for the S. aureus detection. The MPDA/MnO 2 nanozymes possess excellent oxidase-like activity and electrochemical property. MPDA/MnO 2 nanozymes can catalyze the oxidation of TMB to generate TMB+ (blue color) and TMB2+ (yellow color) products. The oxidase-like activity of MPDA/MnO 2 can be inhibited when the SA31 is adsorbed on the surface of the nanozymes. In the presence of S. aureus, SA31 aptamer desorbs from MPDA/MnO 2 surface based on the specific identification between S. aureus and aptamer, resulting in the recovery of their oxidase-like activity. Based on the different oxidative degree of TMB, the color of sensing solution changes from blue to yellow, the electrochemical signals also have changed simultaneously. The colorimetric-electrochemical sensing platform can accurately detect S. aureus, showing a low detection limit in 3 CFU/mL (S/N = 3). Furthermore, the dual-mode sensing platform can be utilized for the accurate and specific detection of S. aureus in real sample with the recovery of 95.15%− 115.28%. This work based on SA31 aptamer-tunable oxidase-like activity of MPDA/MnO 2 nanozymes provides a dual-mode assay for specific and accurate detection of S. aureus. • A dual-modal strategy was designed to detect S. aureus based on the colorimetric-electrochemical sensing platform. • The SA31 can regulate the oxidase-like activity by adsorption and desorption on the surface of MPDA/MnO 2 nanozymes. • The electrochemical behavior of the electrode can be adjusted by the specific binding between aptamers and S. aureus. • This dual-modal sensing platform possesses low detection limit (3 CFU/mL) and wide linear range. [ABSTRACT FROM AUTHOR]

We report on a highly sensitive electrochemical biosensor for determination of cholesterol. The biosensor was fabricated by co-immobilizing bi-enzymes, cholesterol oxidase (ChOx), and horseradish peroxidase (HRP). Voltammetric technique such as cyclic voltammetry and impedance experiment were used to study the characterization of modified electrode step by step. The developed sensor is cheap, disposable, portable and exhibits higher sensitivity. The biosensor expressed a wide linear range up to 300 mg dL in a physiological condition (pH 7.0), with a correlation coefficient of 0.9969. A sensitivity of 13.28 μA mg dL cm which makes it very promising for the clinical determination of cholesterol. [ABSTRACT FROM AUTHOR]

Sensitive detection and effective inactivation of bacteria are essential in preventing foodborne bacterial infection that poses a significant threat to human health. Herein, a near-infrared (NIR)-driven multifunctional photoelectrochemical (PEC) biosensor was constructed for detection and inactivation of S. aureus. Based on the covalent bonding between amine and carboxyl groups, carboxyl-functionalized SA31 aptamer was immobilized on the PDA/MnO 2 photoelectrode. In the presence of S. aureus , SA31 aptamer can specifically capture S. aureus , causing the decrease of photocurrent signal owing to steric hindrance effect. Leveraging photocurrent-off signal, there existed a satisfied linear relationship between the photocurrent variation and the logarithm of S. aureus concentration, achieving a wide linear range from 10 to 107 CFU/mL with a low detection limit of 2.0 CFU/mL. Notably, PDA/MnO 2 with peroxidase-like activity facilitated the catalytic oxidation of S. aureus with assistance of hydrogen peroxide (H 2 O 2) to cause the inactivation of S. aureus. Desorption of inactivated S. aureus from the photoelectrode led to a recovery of photocurrent signal, enabling a "signal on" switch. Simultaneously, the excellent photothermal performance of the PDA/MnO 2 converted light energy into heat energy under the irradiation of NIR light (808 nm, 1.5 W/cm2), triggering the synergistic antibacterial effect against S. aureus (97.36%). This work provides a novel strategy for fabricating the detection and inactivation of bacteria in practical applications. [ABSTRACT FROM AUTHOR]

It is important to obtain the targeted nanocarriers during cancer treatment. Herein, mannosylated liposomes encapsulating carbon dots (CDs) are provided for targeted recognition of liver cancer HepG2 cells, which is based on the specific interaction between D -mannose and glycoprotein on the surface of HepG2 cells. CDs were prepared by hydrothermal method. Then, they were encapsulated into liposomes by hydrophobic force. The encapsulation of CDs into liposomes increases their stability and fluorescence intensity. Furthermore, D -mannose can also be inserted into liposomes by the aldehyde amine reaction between aldehyde groups of mannose molecules and amino groups of liposomes. The obtained D -mannose-CDs-liposomes (Man-CDs-liposomes) exhibit selectively tracking and efficiently labelling for cancer cells. The work highlights the potential application of CDs for bioimaging and diagnostic. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to investigate how dark septate endophytes (DSE) from arid habitats affect host growth and their application to crops and medicinal plants in drought-prone soils. Methods: First, the osmotic-stress tolerance of Paraphoma sp., Embellisia chlamydospora, and Cladosporium oxysporum, isolated from Hedysarum scoparium, was tested using osmotically adjusted pure culture. Second, we examined the performance of host (H. scoparium) and non-host (Glycyrrhiza uralensis and Zea mays) plants inoculated with these fungi under mild (MD) and extreme drought (ED) conditions in a growth chamber. Results: All the DSE showed high tolerance to osmotic stress in vitro and could colonise the roots of all the plants. For H. scoparium, DSE improved the root biomass and length depending on DSE species, with Paraphoma sp. and C. oxysporum exhibiting positive effects under all the drought treatments. For G. uralensis and Z. mays, DSE inoculation enhanced the root development of plants under MD condition and was dependent on the plant–fungus species. However, this positive effect was weakened under extreme drought stress. Conclusions: DSE isolated from H. scoparium enhanced the root growth of the host plant under drought conditions and may also be used to promote the cultivation of agricultural and medicinal plants. [ABSTRACT FROM AUTHOR]

Gold nanoclusters have attracted widespread attention because of their unique optical and physical properties. However, traditional synthesis methods are complicated and require additional reducing agents, while the yield is often very low. Such resource and time-consuming synthesis processes limit their further application. Herein, a rapid sonochemical route is used to synthesize fluorescent Au nanoclusters in large quantities using glutathione (GSH) both as a capping and reducing agent. These Au nanoclusters are synthesized quickly (∼40 min) due to the presence of ultrasonic waves, and show orange red photoluminescence (Em = 598 nm), small size (∼2 nm) and good dispersion in aqueous solution. Moreover, GSH, as a protecting agent on the surface of resultant Au nanoclusters, has many functional groups including carboxyl and amino groups because of which the nanoclusters show high photo-, storage-, metal- and pH-stability. A stable Au nanoclusters-based nano-sensor is designed for highly sensitive and selective label-free detection of Cu2+ with a low limit of detection of 7 ppb (based on S/N = 3). The fluorescent probe can be used in versatile nanothermometry devices, because their photoluminescence intensity correlates strongly with temperature and varies considerably over a wide temperature range (20–80 °C). Therefore, the novel fluorescent sensing probe has great application prospects in Cu2+ detection and temperature sensing. [ABSTRACT FROM AUTHOR]

Dark septate endophytes (DSE) are diverse facultative biotrophic ascomycetes that ubiquitously colonise plant roots and may facilitate plant growth and productivity. However, the relationship between DSE resources and medicinal plants is still unclear. Here, we investigated DSE colonisation and species composition associated with roots of 25 medicinal plants collected from Anguo Medicine Planting Site in the farmland habitat, northern China in May 2017 using morphological characteristics and ITS sequencing. Typical DSE colonisation structures were observed in the roots of 25 medicinal plants. Total DSE colonisation was in the range of 2.22–100% and was significantly and positively correlated with soil organic matter, urease, and phosphatase. Host species purely explained 80.8%, 74.0%, and 79.0% of the observed variation in hyphal, microsclerotial, and total DSE colonisation, respectively. Of the 14 DSE taxa isolated from all 25 medicinal plant roots, six species were reported here for the first time in medicinal plants. Nonmetric multidimensional scaling analysis revealed that DSE colonisation and species composition significantly differed between different plant species. The DSE colonisation and species composition were predominately affected by plant identity than by soil factors. We conclude that the dynamics of DSE in the roots of medicinal plants exhibited a highly correlated plant species pattern, which further correlated with soil nutrient availability and enzymatic activity. This research provides a basis for further understanding of the ecological functions of DSE and their roles in the promotion of yield and quality of medicinal plants in the farmland ecosystems. • Twenty-five medicinal plants were colonised by dark septate endophytes (DSE). • Six DSE species were reported here in medicinal plants for the first time. • DSE colonisation and species composition were mainly affected by plant identity than by soil factors. • Soil organic carbon, urease, and phosphatase were the main DSE colonisation predictors. [ABSTRACT FROM AUTHOR]