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In this work, we demonstrate that monodispersed hollow mesoporous organosilica nanospheres (MONs) and yolk-shell MONs possessing controlled core cavity and mesoporous shell is successfully synthesized through a one-pot approach, which involves co-condensation of 3-aminopropyltriethoxysilane and 1,2-bis(triethoxysilyl)ethane templated by lauryl sulfonate betaine and sodium dodecyl benzenesulfonate. The MONs present an open mesoporosity, hollow cavity with a morphology tailored by the various core templates, and high surface area (328 m2/g). In addition, the composition of the hollow MONs could be further tuned through the same approach. The as-prepared hollow MONs as adsorbent deliver an enormous adsorption capacity (414 mg/g) towards the removal of Pb2+ from water solution. Importantly, the prepared hollow MONs present acceptable recycling and stability, since the performance in Pb2+ removal from water remains above 80 % even after 5 consecutive cycles. The adsorption of Pb2+ on hollow MONs follows the pseudo-second-order mechanics and Langmuir isotherm models. The results confirm hollow MONs exhibit considerable promise for the remarkably efficient separation of Pb2+ ions in water solution. The hollow MONs with different compositions and yolk-shell structured MONs with different shapes are successfully synthesized via one-step dual-template synthetic approach. [Display omitted] • Hollow mesoporous organosilica nanospheres (MONs) were prepared by a simple one-step dual-template method. • The approach is applicable to the synthesis of hollow and yolk-shell MONs. • Different compositons and morphologies could be constructed on the MONs. • Hollow MONs reveal high adsorption performance for heavy metal ions Pb2+ and acceptable recycling and stability. [ABSTRACT FROM AUTHOR]

The social division of labor within the honeybee colony is closely related to the age of the bees, and the age structure is essential to the development and survival of the colony. Differences in tolerance to pesticides and other external stresses among worker bees of different ages may be related to their social division of labor and corresponding physiological states. Pyraclostrobin was widely used to control the fungal diseases of nectar and pollen plants, though it was not friend to honey bees and other pollinators. This work aimed to determine the effects of field recommended concentrations of pyraclostrobin on the activities of protective and detoxifying enzymes, on the expression of genes involved in nutrient metabolism, and immune response in worker bees of different ages determined to investigate the physiological and biochemical differences in sensitivity to pyraclostrobin among different age of worker bees. The result demonstrates that the tolerance of adult worker bees to pyraclostrobin was negatively correlated with their age, and the significantly reduced survival rate of forager bees (21 day-old) with continued fungicide exposure. The activities of protective enzymes (CAT and SOD) and detoxifying enzymes (CarE, GSTs and CYP450) in different ages of adult worker bees were significantly altered, indicating the physiological response and the regulatory capacity of worker bees of different ages to fungicide stress was variation. Compared with 1 and 8 day-old worker bees, the expression of nutrient-related genes (ilp1 and ilp2) and immunity-related genes (apidaecin and defensin1) in forager bees (21 day-old) was gradually downregulated with increasing pyraclostrobin concentrations. Moreover, the expression of vitellogenin and hymenoptaecin in forager bees (21 day-old) was also decreased in high concentration treatment groups (250 and 313 mg/L). The present study confirmed the findings of the chronic toxicity of pyraclostrobin on the physiology and biochemistry of worker bees of different ages, especially to forager bees (21 day-old). These results would provide important physiological and biochemical insight for better understanding the potential risks of pyraclostrobin on honeybees and other non-target pollinators. [Display omitted] • Worker bees regulate enzyme activities to minimize pyraclostrobin stress. • Pyraclostrobin disordered nutrient metabolism and energy storage. • Pyraclostrobin disrupted the humoral immunity of foragers. • Pyraclostrobin stress on the physiology of worker bees affects their age-dependent behavioral tasks. [ABSTRACT FROM AUTHOR]

Graphical abstract The high temperature asphalt was preoxidized and carbonized before acid oxidation to prepared graphene quantum dots. Stepwise, the graphene quantum dots was neutralized with ammonia and hydrothermal treated. The as-synthesized graphene quantum dots can emit bright yellow fluorescence, and it have fluorescent quenching effect while mixed with Fe3+ solution, hence, it was applied as an effective fluorescent sensing probe to detect Fe3+ ions. Highlights • Graphene quantum dots were firstly prepared using high -softening point asphalt. • Amino-functionalized graphene quantum dots were successfully synthesized. • Amination and amidation were found to be the underlying mechanisms of fluorescence enhancement in af-GQDs. • A superior detection limit of 0.51 nM was achieved by af-GQDs in Fe3+ detection. Abstract Graphene quantum dots (GQDs) are known to display tunable photoluminescence (PL) proprieties by functional modification. Here, yellow fluorescence amino-functionalized GQDs (af-GQDs) were synthesized using high-softening point asphalt as precursor and ammonia as nitrogen source, and the mechanism of fluorescence enhancement by nitrogen-containing functional groups is also discussed in detail. The photoluminescence quantum yield (QY) of the resultant GQDs increased from 4.7% to 13.8% after the amino-hydrothermal treatment. Transmission electron microscopy (TEM) images showed that the af-GQDs have more uniform size distribution than GQDs. PL and ultraviolet–visible spectrum (UV–Vis) suggested that two types of electron transitions namely π-π∗ and n-π∗ occurred intrinsically in GQDs, and n-π∗ transition of functional groups was more prominent in af-GQDs. Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) analyses demonstrated that reduction reactions occurred on the surface of GQDs, and nitrogen functional groups were introduced into GQDs during the amino-hydrothermal treatment process. Ultraviolet photoelectron spectroscopy (UPS) results confirmed that the energy level of the highest occupied molecular orbit increased from 6.98 to 7.26 eV. The amide and amino groups were considered to contribute to the fluorescence enhancement of GQDs. Furthermore, the af-GQDs were used as effective fluorescent sensing probes to detect Fe3+ ions, which have a high sensitivity, good selectivity, and superior detection limit of 0.51 nM, indicating their promising application in trace Fe3+ ion detection. [ABSTRACT FROM AUTHOR]

The receptor protein PEX5, an important component of peroxisomes, regulates growth, development, and immunity in yeast and mammals. PEX5 also influences growth and development in plants, but whether it participates in plant immunity has remained unclear. Here, we report that knockdown of OsPEX5 enhances resistance to the rice blast fungus Magnaporthe oryzae. We demonstrate that OsPEX5 interacts with the E3 ubiquitin ligase APIP6, a positive regulator of plant immunity. APIP6 ubiquitinates OsPEX5 in vitro and promotes its degradation in vivo via the 26S proteasome pathway. In addition, OsPEX5 interacts with the aldehyde dehydrogenase OsALDH2B1, which functions in growth-defense trade-offs in rice. OsPEX5 stabilizes OsALDH2B1 to enhance its repression of the defense-related gene OsAOS2. Our study thus uncovers a previously unrecognized hierarchical regulatory mechanism in which an E3 ubiquitin ligase targets a peroxisome receptor protein that negatively regulates immunity in rice by stabilizing an aldehyde dehydrogenase that suppresses defense gene expression. [Display omitted] • OsPEX5 negatively regulates immunity in rice • OsPEX5 interacts with and is ubiquitinated by APIP6 • APIP6 positively regulates the plant response to rice blast by degrading OsPEX5 • OsPEX5 stabilizes OsALDH2B1 to increase its inhibitory effect on OsAOS2 The peroxisomal receptor protein PEX5 is a crucial component of peroxisomes. You et al. show that OsPEX5, modulated by the E3 ubiquitin ligase APIP6, negatively regulates immunity in rice. In addition, OsPEX5 interacts with and stabilizes the aldehyde dehydrogenase OsALDH2B1 to inhibit the expression of the defense gene OsAOS2. [ABSTRACT FROM AUTHOR]

In this work, BiVO 4 films are firstly synthesized, followed by electrodepositing of Cu 2 O to construct BiVO 4 /Cu 2 O heterojunction electrodes for photoelectrochemical water splitting. By regulating the electrodeposition potential, it is possible to control that Cu 2 O is deposited on the surface or inside of BiVO 4 , which enables them n-type or p-type semiconductivity behavior for oxygen and hydrogen evolution reactions, respectively. Due to the built-in electric field of p-n heterojunction and the Co-Pi co-catalyst layer, the anodic photocurrent density of optimized BiVO 4 /Cu 2 O/Co-Pi photoanode reaches 1.97 mA cm−2 at 1.23 V vs. RHE. In the meantime, the deposition of Cu 2 O inside BiVO 4 has reversed the arrangement of the BiVO 4 /Cu 2 O heterogeneous structure. The cathodic photocurrent density of the fabricated BiVO 4 /Cu 2 O-C photocathode shows − 2.9 mA cm−2. Furthermore, the unbiased solar tandem cell is fabricated using BiVO 4 /Cu 2 O-C photocathode and BiVO 4 /Cu 2 O/Co-Pi photoanode, which exhibits 0.1 mA cm−2 in the photoelectrochemical cell without applying any external voltage. [Display omitted] • BiVO4 decorated with Cu2O can be served as photoanodes. • By varying electrodeposition potential, the as-fabricated hybrid BiVO4/Cu2O photoelectrodes also exhibited photocathodes character. • The unique distribution location of Cu2O renders it to form anticipant heterojunctions with opposite conductive types. • The BVO/Cu2O/Co-Pi—BVO/Cu2O-C tandem cell exhibited 0.78 mA cm−2 of Jop. [ABSTRACT FROM AUTHOR]

In recent years, electromyography (EMG) signals have been widely used in human–machine interfaces (HMIs). Musculoskeletal models (MMs) have been employed to decode human movement intentions from EMG signals in HMIs. Non-negative matrix factorization (NMF) has been adopted to extract neural control information from surface EMG signals. The aim of this study was to investigate if the NMF could extract the control information from surface EMG signals to substitute muscle activations of the deep muscles of the MM. An enhanced MM based on NMF (NMF-MM) was proposed to predict wrist pronation/supination (Pro/Sup) joint angles from surface EMG signals. We extracted the muscle activations of a pair of virtual agonist–antagonistic muscles with NMF from multi-channel EMG signals and inputted the extracted signals into the MM. Eight able-bodied subjects were recruited and tested in four different upper limb postures. Eight bipolar electrodes were attached to the upper forearm to record EMG signals. The Pearson's correlation coefficient (r) and the normalized root mean square error (NRMSE) between measured and predicted joint angles were adopted to quantify the performance of the decoding methods. The performance of the proposed NMF-MM was compared with that of the NMF, linear regression (LR), artificial neural network (ANN), LR based on NMF (NMF-LR), ANN based on NMF (NMF-ANN), LR based on time-domain features (TD-LR), and ANN based on time-domain features (TD-ANN). The results demonstrated that the NMF-MM outperformed the other methods with higher prediction accuracy and better robustness. This study proposed a promising method for predicting continuous and coordinated movements in HMIs. • Control information was extracted from EMG signals to replace deep muscle activation. • An enhanced MM based on NMF was proposed to predict wrist Pro/Sup joint angles. • The prediction performance of proposed NMF-MM was compared with that of the SOA. • The results indicated that NMF-MM could predict continuous and coordinated movements. [ABSTRACT FROM AUTHOR]

[Display omitted] • Energy band structure of BiOI-TiO 2 heterojunction helped to improve PEC performance. • The p-type semiconductor BiOI has visible light absorption. • The built-in electric field of p-n heterojunction, which provides a driving force promoting the separation of photoexcited carriers. • The concept of p-n heterojunction, and type-II energy structure were simultaneously applied for a synergetic effect. The construction of p-n heterojunction is one of the effective strategies to improve the spatial charge separation due to built-in electric field. In this study, the p-type BiOI ultrathin 2D nanoplates decorated n-type TiO 2 nanosheets arrays (TNS) heterojunction photoanode was successfully fabricated through hydrothermal methods. The photocurrent density achieved for optimized BiOI/TNS photoanode was 0.54 mA cm−2 at 1.23 V vs. RHE, which is 15 times higher than that of unmodified TNS photoelectrode (0.036 mA cm−2) under simulated sunlight irradiation without any cocatalyst. In addition, the onset potential of BiOI/TNS photoanodes has a certain negative shift from 0.5 to 0.3 V, which can demonstrate BiOI/TNS photoanodes possesses better catalytic activity and kinetics for water oxidation. The excellent photoelectrochemical activity of BiOI/TNS could be attributed to the type-II energy structure of BiOI/TiO 2 photoanode, the built-in electric field of p-n heterojunction, and TiO 2 nanosheets arrays with high exposed {0 0 1} facets. [ABSTRACT FROM AUTHOR]

Serious pollution is caused by heavy metals (HMs) emission during sludge combustion treatment, but the addition of minerals has the ability to alleviate the migration of HMs to the gaseous state. In this study, HMs (As, Cr, Zn and Cu) behavior, speciation, and environmental risk during sludge combustion with CaO and montmorillonite (MMT) additive was investigated in the lab-scale tube furnace. The results showed that the sludge combustion was mainly determined by volatile matter. In general, CaO inhibited the volatilization of Cr, Zn, and Cu, but promoted As volatilization. MMT inhibited the volatilization of HMs, but the effect was not obvious at high temperatures. Besides, the improvement of retention effect was not found for Cr and Cu with the increase of CaO at 1000 °C, there might exist threshold value for CaO on HMs retention process. Meanwhile, CaO increased acid-soluble fraction of As significantly at high temperatures, decreased residual fraction of Cr by oxidation, converted Zn and Cu to residual fraction. MMT increased the acid-soluble fraction of As and residual fraction of Cr. In view of the HMs environmental risk in ash, the combustion temperature of sludge was necessary to control under 1000 °C and minerals additive amount was needed to manage above 1000 °C. [Display omitted] • CaO inhibited the volatilization of Cr, Zn, and Cu, but promoted As on the whole. • "Adsorption invalidation" by montmorillonite additive was found at high temperatures. • There was a high correlation between temperature and heavy metals speciation. • CaO increased acid-soluble fraction of As above 1000 °C, decreased residual fraction of Cr. • Minerals additive amount was needed to manage during sludge combustion above 1000 °C. [ABSTRACT FROM AUTHOR]