ATAD3B is a mitophagy receptor mediating clearance of oxidative stress-induced damaged mitochondrial DNA.

Mitochondrial DNA (mtDNA) encodes several key components of respiratory chain complexes that produce cellular energy through oxidative phosphorylation. mtDNA is vulnerable to damage under various physiological stresses, especially oxidative stress. mtDNA damage leads to mitochondrial dysfunction, and dysfunctional mitochondria can be removed by mitophagy, an essential process in cellular homeostasis. However, how damaged mtDNA is selectively cleared from the cell, and how damaged mtDNA triggers mitophagy, remain mostly unknown. Here, we identified a novel mitophagy receptor, ATAD3B, which is specifically expressed in primates. ATAD3B contains a LIR motif that binds to LC3 and promotes oxidative stress-induced mitophagy in a PINK1-independent manner, thus promoting the clearance of damaged mtDNA induced by oxidative stress. Under normal conditions, ATAD3B hetero-oligomerizes with ATAD3A, thus promoting the targeting of the C-terminal region of ATAD3B to the mitochondrial intermembrane space. Oxidative stress-induced mtDNA damage or mtDNA depletion reduces ATAD3B-ATAD3A hetero-oligomerization and leads to exposure of the ATAD3B C-terminus at the mitochondrial outer membrane and subsequent recruitment of LC3 for initiating mitophagy. Furthermore, ATAD3B is little expressed in m.3243A > G mutated cells and MELAS patient fibroblasts showing endogenous oxidative stress, and ATAD3B re-expression promotes the clearance of m.3243A > G mutated mtDNA. Our findings uncover a new pathway to selectively remove damaged mtDNA and reveal that increasing ATAD3B activity is a potential therapeutic approach for mitochondrial diseases.

The epigenetic regulatory mechanism of PIWI/piRNAs in human cancers.

PIWI proteins have a strong correlation with PIWI-interacting RNAs (piRNAs), which are significant in development and reproduction of organisms. Recently, emerging evidences have indicated that apart from the reproductive function, PIWI/piRNAs with abnormal expression, also involve greatly in varieties of human cancers. Moreover, human PIWI proteins are usually expressed only in germ cells and hardly in somatic cells, so the abnormal expression of PIWI proteins in different types of cancer offer a promising opportunity for precision medicine. In this review, we discussed current researches about the biogenesis of piRNA, its epigenetic regulatory mechanisms in human cancers, such as N6-methyladenosine (m6A) methylation, histone modifications, DNA methylation and RNA interference, providing novel insights into the markers for clinical diagnosis, treatment and prognosis in human cancers.

Diet and Adaptive Evolution of Alanine-Glyoxylate Aminotransferase Mitochondrial Targeting in Birds.

Adaptations to different diets represent a hallmark of animal diversity. The diets of birds are highly variable, making them an excellent model system for studying adaptive evolution driven by dietary changes. To test whether molecular adaptations to diet have occurred during the evolution of birds, we examined a dietary enzyme alanine-glyoxylate aminotransferase (AGT), which tends to target mitochondria in carnivorous mammals, peroxisomes in herbivorous mammals, and both mitochondria and peroxisomes in omnivorous mammals. A total of 31 bird species were examined in this study, which included representatives of most major avian lineages. Of these, 29 have an intact mitochondrial targeting sequence (MTS) of AGT. This finding is in stark contrast to mammals, which showed a number of independent losses of the MTS. Our cell-based functional assays revealed that the efficiency of AGT mitochondrial targeting was greatly reduced in unrelated lineages of granivorous birds, yet it tended to be high in insectivorous and carnivorous lineages. Furthermore, we found that proportions of animal tissue in avian diets were positively correlated with mitochondrial targeting efficiencies that were experimentally determined, but not with those that were computationally predicted. Adaptive evolution of AGT mitochondrial targeting in birds was further supported by the detection of positive selection on MTS regions. Our study contributes to the understanding of how diet drives molecular adaptations in animals, and suggests that caution must be taken when computationally predicting protein subcellular targeting.

Adverse Effects of Inherent CaO in Coconut Shell-Derived Activated Carbon on Its Performance during Flue Gas Desulfurization.

Activated carbon has been used commercially to remove SO2 from coal combustion flue gas. However, the role of inherent CaO in activated carbon is uncertain. In this study, the adverse effects of inherent CaO in the activated carbon derived from coconut shell (CSAC) on its desulfurization performance were systematically studied at the temperature range of 60-100 °C in a fixed-bed reactor. The solid sorbent samples were analyzed using scanning electron microscopy, X-ray diffraction, X-ray fluorescence, Fourier transform infrared spectroscopy, and Brunauer-Emmett-Teller analysis. The flue gas compositions were analyzed by using an online flue gas analyzer. The experimental results showed that the inherent CaO had a profoundly adverse influence on the desulfurization capacity and efficiency of CSAC at all of the temperatures studied. This adverse influence was clearly identified by a comparison of the desulfurization performance of the raw CSAC to those of the acid-washed CSAC samples. It was found that the removal of the inherent CaO from CSAC using a pretreatment of HCl aqueous solution led to an increase in the desulfurization capacity of 41.7%. The adverse effects were attributed to the conversion of CaO into dihydrate calcium sulfate whiskers which formed solid crystals that blocked the micropores of the CSAC particles.

In Situ Synthesis of Pt/TiO2 Nanosheets on Flexible Ti Mesh for Efficient and Cyclic Phenol Removal.

TiO2 nanostructures that feature a two-dimensional (2D) morphology have attracted extensive attention in environment processing and energy conversion fields owing to their peculiarly large surface area and superior transfer efficiency of photogenerated carriers. In this work, we proposed a hybrid approach including a plasma electrolyte oxidation (PEO) and ion exchange strategy to in situ synthesize TiO2 nanosheets on a flexible Ti mesh substrate, in which the layered Na2Ti2O5 nanosheets were fabricated as a template. The TiO2 nanosheets are crystalline anatase phase and exhibit excellent photocatalytic activity and stability in removing phenol. With the modification of the Pt cocatalyst, the phenol degradation performance has been significantly enhanced. More importantly, the in situ grown TiO2 nanosheets on the flexible Ti mesh provide strong substrate adhesion that enables superior photocatalytic stability for cyclic degradation of phenol. It can be expected that the synthetic strategy proposed in this work can pave a solid way toward the in situ growth of various TiO2-based composite nanophotocatalysts with sufficient active sites and excellent photocatalytic properties, and thus, it will open up more opportunities for environment processing and energy conversion.

Mechanistic Study of Selective Absorption of NO in Flue Gas Using EG-TBAB Deep Eutectic Solvents.

The selective absorption of NO in flue gas has been investigated using a series of deep eutectic solvents (DESs) as novel denitrifying agents. The EG-TBAB DESs used in this work are composed of a hydrogen donor ethylene glycol (EG) and a parent salt tetrabutylammonium bromide (TBAB). Effects of DES composition (EG:TBAB molar ratio), operation temperature, residence time, and O2 concentration in the flue gas on denitrification performances of EG-TBAB DESs have been investigated. The highest denitrification efficiency and capacity were achieved using EG to TBAB molar ratio of 50:1 at an operation temperature of 50 °C. The O2 partial pressure in the flue gas showed no noticeable effects on NO absorption in EG-TBAB DESs. EG-TBAB DESs maintain high denitrification stability after five absorption-desorption cycles. The calculated absorption equilibrium constant ( K0) and Henry's law constant ( H) showed that EG-TBAB DESs exhibited high absorption capacity for NO molecules, indicating that they are applicable in industrial denitrification processes. The kinetics analysis of NO absorption in EG-TBAB DESs indicated that EG-TBAB DESs could effectively absorb NO and the absorption of NO was strongly influenced by mass transfer.

Resilient Time-Varying Formation Tracking Control for General Linear Multiagent Systems With a Nonautonomous Leader and Adversarial Followers.

This article is concerned with resilient formation tracking problems for general linear multiagent systems, where the leader's control input is unavailable to all the followers and partial followers' behaviors are malicious due to the node attacks. Despite the presence of the nonautonomous leader and the adversarial followers, the remaining benign followers are still expected to track the leader's trajectory with the prescribed time-varying formation. To this end, a resilient scheme comprising an attack detection and isolation strategy and a formation tracking protocol is proposed. The detection strategy enables every benign follower to identify its adversarial neighbors with two-hop communication information, as long as the underlying topology meets given conditions. Then, the detected adversarial agents are directly removed to avoid the spread of their influence, which induces a new problem called node loss. To accommodate possible node loss events, the designed tracking protocol is independent of certain global knowledge, and its convergence is demonstrated by means of the impulsive Lyapunov functions. Finally, the proposed resilient scheme is verified by two simulation examples.

Coal-based carbon nanosheets contained carbon microfibers modified with grown carbon nanotubes as efficient air electrode material for rechargeable zinc-air batteries.

Coal-based oxygen electrocatalysts hold immense promise for cost-effective applications in rechargeable Zn-air batteries (ZABs) and the value-added, clean utilization of traditional coal resources. Herein, an electrospun membrane electrode comprising coal-derived carbon nanosheets and directly grown carbon nanotubes (CNS/CMF@CNT) was successfully synthesized. The hierarchical porous structure of the electrode, composed of multiple components, significantly facilitates mass and ion transportation, resulting in exceptional electrochemical performance. Employing Fe as the catalyst for CNT growth, the CNS/CMF@CNT electrode exhibits a remarkable onset potential of 0.96 V and a half-wave potential of 0.87 V in the oxygen reduction reaction (ORR). In-situ surface-enhanced Raman spectroscopy reveals that hydroxyl radical desorption on the surface of CNS/CMF@CNT(Fe) is the rate-determining step of the ORR. Notably, the aqueous ZAB featuring the CNS/CMF@CNT(Fe) electrode achieved a peak power density of 216.0 mW cm-2 at a current density of 414 mA cm-2 and maintained a voltage efficiency of 65.1 % after 2000 charge/discharge cycles at 5 mA cm-2. Furthermore, the all-solid-state ZAB incorporating this electrode displayed an open-circuit voltage of 1.43 V, a peak power density of 70.1 mW cm-2 at a current density of 110 mA cm-2, and a voltage efficiency of 66.5 % after 150 charge/discharge cycles. The utilization of abundant coal as the raw material for electrode fabrication not only brings conceivable economic benefits in ZAB construction, but also commendably advances the effective application of traditional coal resources in a more sustainable manner.

Distributed output formation tracking control of heterogeneous multi-agent systems using reinforcement learning.

This paper studies the distributed time-varying output formation tracking problem for heterogeneous multi-agent systems with both diverse dimensions and parameters. The output of each follower is supposed to track that of the virtual leader while accomplishing a time-varying formation configuration. First, a distributed trajectory generator is proposed based on neighboring interactions to reconstitute the state of virtual leader and provide expected trajectories with the formation incorporated. Second, an optimal tracking controller is designed by the model-free reinforcement learning technique using online off-policy data instead of requiring any knowledge of the followers' dynamics. Stabilities of the learning process and resulting controller are analyzed while solutions to the output regulator equations are equivalently obtained. Third, a compensational input is designed for each follower based on previous learning results and a derived feasibility condition. It is proved that the output formation tracking error converges to zero asymptotically with the biases to cost functions being restricted arbitrarily small. Finally, numerical simulations verify the proposed learning and control scheme.

Cross-interaction of volatiles in fast co-pyrolysis of waste tyre and corn stover via TG-FTIR and rapid infrared heating techniques.

Using fast infrared heating technology to minimize the pyrolysis temperature differential and optimizing secondary reactions is advantageous for studying co-pyrolysis behaviors. In this study, the co-pyrolysis behaviors of waste tyres (WT) and corn stover (CS), including product distribution, pyrolysis kinetics, and thermodynamics, were studied using TGA-FTIR analysis and fast infrared heating reactor. The DTG curves for the co-pyrolysis of WT and CS significantly differed from the calculated values, implying that the pyrolysis intermediates produced by CS during the pyrolysis process may have synergetic effects with the pyrolysis of WT. The apparent activation energies using the Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods were similar, 244.88 kJ/mol and 245.93 kJ/mol, respectively. The experiment results suggest that the bio-oil yield increased first and then decreased with a further temperature increase. The yield of bio-oil gradually increased from 35.36% to 46.06% as temperature rose from 500 °C to 700 °C; but the further increasing to 800 °C decreased the bio-oil yield to 40.72%. The aromatic compounds in tar gradually increased with increasing the temperature, while the aliphatic compounds increased initially and then reduced. Meanwhile, the oxygenated compounds first decreased and then increased with increasing the pyrolysis temperature. The yield of light oil components (C＜10) increased from 5.11% at 400 °C to 7.71% at 700 °C. A further increase in the pyrolysis temperature to 800 °C reduced the light oil content to 4.93%.

Measurement based dimension descent association algorithm for OTHR multi-detection multi-target tracking.

The problem of multi-detection multi-target tracking (MDMTT) using over-the-horizon radar in dense clutter environment is studied in this paper. The biggest challenge of MDMTT is the 3-dimensional multipath data association among measurements, detection models and targets. In particular, a lot of clutter measurements are generated in dense clutter environment, which increase the computational burden of 3-dimensional multipath data association greatly. A measurement based dimension descent association (DDA) algorithm is proposed to solve the 3-dimensional multipath data association, which decomposes the 3-dimensional multipath data association into two 2-dimensional data associations. The proposed algorithm can reduce the computational burden compared with the optimal 3-dimensional multipath data association and the computational complexity is analyzed. Besides, a time extension method is designed to detect the new-born targets that appear in the tracking scene, which is based on the sequential measurements. The convergence of the proposed measurement based DDA algorithm is analyzed. The estimation error can convergence to 0 as the number of Gaussian mixtures tends to infinity. The effectiveness and rapidity of the measurement based DDA algorithm are demonstrated by the comparative simulation with the previously proposed algorithms.

S/N-codoped carbon nanotubes and reduced graphene oxide aerogel based supercapacitors working in a wide temperature range.

Among many supercapacitor electrode materials, carbon materials are widely used due to their large specific surface area, good electrical conductivity and high economic efficiency. However, carbon-based supercapacitors face the challenges of low energy density and limited operating environment. This work reports a facile self-assembled method to prepare three-dimensional carbon nanotubes/reduced graphene oxide (CNTs/rGO) aerogel material, which was applied as both positive and negative electrodes in a symmetric superacapacitor. The fabricated supercapacitor exhibited prominent capacitive performance not only at room temperature, but also at extreme temperatures (-20 âˆ¼ 80 °C). The specific capacitances of the symmetric supercapacitors based on CNTs/rGO at a weight ratio of 2:5 respectively reached 107.8 and 128.2 F g-1 at 25 °C and 80 °C with KOH as the electrolyte, and 80.0 and 144.6 F g-1 at -20 °C and 60 °C with deep eutectic solvent as the electrolyte. Notably, the capacitance retention and coulombic efficiency of the assembled supercapacitors remained almost unchanged after 20,000 cycles of charge/discharge test over a wide temperature range. The work uncovered a possibility for the development of high-performance supercapacitors flexibly operated at extreme temperatures.

Hypoxia-reprogramed megamitochondrion contacts and engulfs lysosome to mediate mitochondrial self-digestion.

Mitochondria are the key organelles for sensing oxygen, which is consumed by oxidative phosphorylation to generate ATP. Lysosomes contain hydrolytic enzymes that degrade misfolded proteins and damaged organelles to maintain cellular homeostasis. Mitochondria physically and functionally interact with lysosomes to regulate cellular metabolism. However, the mode and biological functions of mitochondria-lysosome communication remain largely unknown. Here, we show that hypoxia remodels normal tubular mitochondria into megamitochondria by inducing broad inter-mitochondria contacts and subsequent fusion. Importantly, under hypoxia, mitochondria-lysosome contacts are promoted, and certain lysosomes are engulfed by megamitochondria, in a process we term megamitochondria engulfing lysosome (MMEL). Both megamitochondria and mature lysosomes are required for MMEL. Moreover, the STX17-SNAP29-VAMP7 complex contributes to mitochondria-lysosome contacts and MMEL under hypoxia. Intriguingly, MMEL mediates a mode of mitochondrial degradation, which we termed mitochondrial self-digestion (MSD). Moreover, MSD increases mitochondrial ROS production. Our results reveal a mode of crosstalk between mitochondria and lysosomes and uncover an additional pathway for mitochondrial degradation.

Functional Carbon from Nature: Biomass-Derived Carbon Materials and the Recent Progress of Their Applications.

Biomass is considered as a promising source to fabricate functional carbon materials for its sustainability, low cost, and high carbon content. Biomass-derived-carbon materials (BCMs) have been a thriving research field. Novel structures, diverse synthesis methods, and versatile applications of BCMs have been reported. However, there has been no recent review of the numerous studies of different aspects of BCMs-related research. Therefore, this paper presents a comprehensive review that summarizes the progress of BCMs related research. Herein, typical types of biomass used to prepare BCMs are introduced. Variable structures of BCMs are summarized as the performance and properties of BCMs are closely related to their structures. Representative synthesis strategies, including both their merits and drawbacks are reviewed comprehensively. Moreover, the influence of synthetic conditions on the structure of as-prepared carbon products is discussed, providing important information for the rational design of the fabrication process of BCMs. Recent progress in versatile applications of BCMs based on their morphologies and physicochemical properties is reported. Finally, the remaining challenges of BCMs, are highlighted. Overall, this review provides a valuable overview of current knowledge and recent progress of BCMs, and it outlines directions for future research development of BCMs.

Methyl 4-(5-meth-oxy-1H-indol-3-yl)benzoate.

In the title compound, C(17)H(15)NO(3), the dihedral angle between the benzene ring and the indole ring system is 22.5 (3)°. In the crystal, mol-ecules are linked by N-H⋯π and C-H⋯O inter-actions.

2-(4-Fluoro-phen-yl)quinoxaline.

In the title compound, C(14)H(9)FN(2), the dihedral angle between the benzene ring and the quinoxaline ring system is 22.2 (3)°. Any aromatic π-π stacking in the crystal must be very weak, with a minimum centroid-centroid separation of 3.995 (2) Å.

Synthesis of Super-Long Carbon Nanotubes from Cellulosic Biomass under Microwave Radiation.

This study reports a novel method for synthesizing super-long carbon nanotubes (SL-CNTs) from cellulose via a microwave treatment process without an external catalyst. CNTs with a length of 0.7-2 mm were obtained via microwave treatment of cellulose biochar temperatures of 1200-1400 °C. Scanning electron microscope (SEM), together with high-resolution transmission electron microscope (HRTEM) results, were used to investigate the changes in the length and morphology of CNTs with respect to treatment temperature. The morphology of CNTs changed from twisted, curved, and threadlike to straight structures. The average length of CNTs after microwave pyrolysis at 600 °C was approximately 600-1800 nm, which after microwave treatment at 1300 °C and 1400 °C increased to about 1-2 mm. X-ray diffractometer (XRD) results confirmed the crystalline structure of CNTs with two prominent peaks at 2θ = 26.3° and 2θ = 43.2° correlating with the graphite (002) and (100) reflections. The ID/IG ratio obtained from Raman spectra of the CNTs decreased to the lowest value of 0.84 after microwave treatment at 1400 °C, implying a high degree of carbon order. The presence of Fe and trace amounts of other elements were confirmed by the energy-dispersive X-ray spectrometer (EDS) and were postulated to have catalyzed the growth of CNTs. The mechanism of the SL-CNTs growth under microwave treatment was proposed and discussed.

Fully Data-Driven Robust Output Formation Tracking Control for Heterogeneous Multiagent System With Multiple Leaders and Actuator Faults.

This article investigates a fully data-driven method to solve the robust output formation tracking control problem for the multiagent system (MAS) under actuator faults. The outputs of the followers are controlled to track those of multiple leaders with respect to a convex point while achieving an expected time-varying formation. To obviate the requirement of various system prior knowledge in typical MAS control, a hierarchical frame is developed with three learning and control stages using the online measured data. First, a distributed adaptive observer is designed to coordinate the state convex of multiple leaders while estimating unknown dynamics. The adaptive mechanism relaxes the demand for global topology. Second, by collecting and reusing the online system data, an off-policy reinforcement learning (RL) method is proposed in a continuous form to acquire nominal feedback gains from partial observations of the followers. Essential system models are learned along with the RL process, while solutions to the output regulation equations are implicitly obtained. Third, a comprehensive robust controller is further presented based on the previous learning results. To address the actuator faults with efficiency loss and bias, the adaptive neural networks and robust compensations are utilized in a model-free manner. The output formation tracking is achieved under a derived feasibility condition while stabilities of the learning and control methods are analyzed. Finally, simulation results demonstrate the validity of this fully data-driven control frame.

Neuroadaptive Output Formation Tracking for Heterogeneous Nonlinear Multiagent Systems With Multiple Nonidentical Leaders.

This article investigates the practical time-varying output formation tracking (TVOFT) problem for heterogeneous nonlinear multiagent systems (MASs) having multiple leaders, where agents herein could have heterogeneous dynamics and interact with each other under event-triggered communications. It is required that the outputs of followers not only track the predefined convex combination of multiple leaders but also achieve the desired time-varying formation simultaneously. The existing works on formation tracking problems for MASs with multiple leaders depend on the assumption that each follower is a well-informed or uninformed follower, where the well-informed follower is required to have all the leaders as its neighbor. To remove the limitation, a fully distributed observer-based formation tracking control protocol is developed and employed. First, an adaptive state observer with an edge-based event-triggered mechanism for estimating the states of multiple leaders is proposed based on the neighboring interactions, which eliminates the unexpected Zeno behavior. Second, a novel observer is constructed for each follower by exploiting the output information of the follower, in which the adaptive neural network (NN)-based approximation is exploited to compensate for the unknown nonlinearity. A practical TVOFT control protocol is then generated by the proposed observers, where the parameters are determined by an algorithm including five steps. With the help of Lyapunov stability theory and output regulation method, a practical TVOFT criterion for the considered closed-loop system is derived. Finally, the effectiveness of the proposed control scheme is illustrated by a numerical example.

A review on removal of mercury from flue gas utilizing existing air pollutant control devices (APCDs).

Mercury is a highly toxic heavy metal pollutant. It is of great significance to develop cost-effective mercury pollution control technologies of coal-fired flue gas. Among various mercury from flue gas removal methods, the application of existing air pollution control devices (APCDs) to remove mercury from flue gas is one of the most valuable methods because it doesn't need to install additional mercury removal equipment, reducing the cost of mercury removal. This review summarizes the recent progress of mercury from flue gas removal by APCDs (e.g., SCR denitration device, WFGD system and dust removal device). SCR denitration device can achieve partial removal of mercury in flue gas through combined with WFGD system, but easy inactivation and poor sulfur/water/heavy metals resistance of SCR catalyzers are still the main problems. WFGD systems can remove most of Hg2+ (80%-95%), but have low treatment ability for Hg0. Various oxidants can effectively oxidize Hg0 into Hg2+. However, traditional oxidants have high prices and secondary pollution due to the formation of by-products. Fabric filters (FFs), electrostatic precipitators (ESPs) and hybrid fabric filters (HFs) can all control the emission of mercury in the flue gas to a certain extent, especially can effectively remove most of HgP and part of Hg2+, but has low removal capacity for Hg0. Compared with ESP, FF has better capture efficiency for Hg2+ and Hg0, and a combination of ESP and FF, that is HF, can effectively improve the mercury removal capacity.