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Concentrating active Pt atoms in the outer layers of electrocatalysts is a very effective approach to greatly reduce the Pt loading without compromising the electrocatalytic performance and the total electrochemically active surface area (ECSA) for the oxygen reduction reaction (ORR) in hydrogen-based proton-exchange membrane fuel cells. Accordingly, a facile, low-cost, and hydrogen-assisted two-step method is developed in this work, to massively prepare carbon-supported uniform, small-sized, and surfactant-free Pd nanoparticles (NPs) with ultrathin ∼3-atomic-layer Pt shells (Pd@Pt3L NPs/C). Comprehensive physicochemical characterizations, electrochemical analyses, fuel cell tests, and density functional theory calculations reveal that, benefiting from the ultrathin Pt-shell nanostructure as well as the resulting ligand and geometric effects, Pd@Pt3L NPs/C exhibits not only significantly enhanced ECSA, electrocatalytic activity, and noble-metal (NM) utilization compared to commercial Pt/C, showing 81.24 m2/gPt, 0.710 mA/cm2, and 352/577 mA/mgNM/Pt in ECSA, area-, and NM-/Pt-mass-specific activity, respectively; but also a much better electrochemical stability during the 10,000-cycle accelerated degradation test. More importantly, the corresponding 25-cm2 H2-air/O2 fuel cell with the low cathodic Pt loading of ∼ 0.152 mgPt/cm2geo achieves the high power density of 0.962/1.261 W/cm2geo at the current density of only 1,600 mA/cm2geo, which is much higher than that for the commercial Pt/C. This work not only develops a high-performance and practical Pt-based ORR electrocatalyst, but also provides a scalable preparation method for fabricating the ultrathin Pt-shell nanostructure, which can be further expanded to other metal shells for other energy-conversion applications.

Background Focused ultrasound (FUS) has excellent characteristics over other non-invasive stimulation methods in terms of spatial resolution and steering capability of the target. FUS has not been tested in the cerebellar cortex and cellular effects of FUS are not fully understood. Objective/hypothesis To investigate how the activity of cerebellar Purkinje cells (PCs) is modulated by FUS with varying pulse durations and pulse repetition frequencies. Methods A glass microelectrode was inserted into the cerebellar vermis lobule 6 from the dorsal side to extracellularly record single unit activity of the PCs in anesthetized rats. Ultrasonic stimulation (500 kHz) was applied through a coupling cone, filled with degassed water, from the posterior side to target the recording area with varying pulse durations and frequencies. Results Simple spike (SS) activity of PCs was entrained by the FUS pattern where the probability of spike occurrences peaked at around 1 ms following the onset of the stimulus regardless of its duration (0.5, 1, or 2 ms). The level of entrainment was stronger with shorter pulse durations at 50-Hz pulse repetition frequency (PRF), however, peri-event histograms spread wider and the peaks delayed slightly at 100-Hz PRF, suggesting involvement of a long-lasting inhibitory mechanism. There was no significant difference between the average firing rates in the baseline and stimulation periods. Conclusion FUS can entrain spiking activity of single cells on a spike-by-spike basis as demonstrated here in the rat cerebellar cortex. The observed modulation potentially results from the aggregate of excitatory and inhibitory effects of FUS on the entire cortical network rather than on the PCs alone.

High energy density and enhanced rate capability are highly sought-after for supercapacitors in today’s mobile world. In this work, polyaniline/titanium carbide (MXene) (PANI/Ti3C2Tx) nanohybrid is synthesized through a facile and cost-effective self-assembly of one-dimensional (1D) PANI nanofibers and two-dimensional (2D) Ti3C2Tx nanosheets. PANI/Ti3C2Tx delivers greatly improved specific capacitance, ultrahigh rate capability (67% capacitance retention from 1 to 100 A·g−1) as well as good cycle stability. Electrochemical kinetic analysis reveals that PANI/Ti3C2Tx is featured with surface capacitance-dominated process and has a quasi-reversible kinetics at high scan rates, giving rise to an ultrahigh rate capability. By using PANI/Ti3C2Tx as positive electrode, an 1.8 V aqueous asymmetric supercapacitor (ASC) is successfully assembled, showing a maximum energy density of 50.8 Wh·kg−1 (at 0.9 kW·kg−1) and a power density of 18 kW·kg−1 (at 26 Wh·kg−1). Moreover, an 3.0 V organic ASC is also elaborately fabricated by using PANI/Ti3C2Tx, achieving an ultrahigh energy density of 67.2 Wh·kg−1 (at 1.5 kW·kg−1) and a power density of 30 kW·kg−1 (at 26.8 Wh·kg−1). The present work not only improves fundamental understanding of the structure-property relationship towards ultrahigh rate capability electrode materials, but also provides valuable guideline for the rational design of high-performance energy storage devices with both high energy and power densities.

Hyperalgesia, which often occurs in people suffering from alcohol use disorder, may drive excessive drinking and relapse. Emerging evidence suggests that the lateral habenula (LHb) may play a significant role in this condition. Previous research suggests that endocannabinoid signaling (eCBs) is involved in drug addiction and pain, and that the LHb contains core components of the eCBs machinery. We report here our findings in rats subjected to chronic ethanol vapor exposure. We detected a substantial increase in endocannabinoid-related genes, including Mgll and Daglb mRNA levels, as well as monoacylglycerol lipase (MAGL) protein levels, as well as a decrease in Cnr1 mRNA and type-1 cannabinoid receptor (CB1R) protein levels, in the LHb of ethanol-exposed rats. Also, rats withdrawing from ethanol exposure displayed hypersensitivity to mechanical and thermal nociceptive stimuli. Conversely, intra-LHb injection of the MAGL inhibitor JZL184, the fatty acid amide hydrolase inhibitor URB597, or the CB1R agonist WIN55,212-2 produced an analgesic effect, regardless of ethanol or air exposure history, implying that alcohol exposure does not change eCB pain responses. Intra-LHb infusion of the CB1R inverse agonist rimonabant eliminated the analgesic effect of these chemicals. Rimonabant alone elicited hyperalgesia in the air-, but not ethanol-exposed animals. Moreover, intra-LHb JZL184, URB597, or WIN55,212-2 reduced ethanol consumption in both homecages and operant chambers in rats exposed to ethanol vapor but not air. These findings suggest that LHb eCBs play a pivotal role in nociception and facilitating LHb eCBs may attenuate pain in drinkers.

A simple, convenient and label-free approach was developed for detection of acetylcholine (ACh) based on competitive enzymatic hydrolysis by use of liquid crystals (LCs) as a sensing medium. Self-assembled monolayers of myristoylcholine (Myr) were obtained at the aqueous/LC interface when the surfactants were in contact with LCs, resulting in a perpendicular orientation of LCs at the interface. Thus, LCs displayed a dark optical image. However, enzymatic hydrolysis of Myr by acetylcholinesterase (AChE) disturbed the Myr monolayers, which led to a horizontal orientation of LCs at the interface, thereby inducing a dark-to-bright shift of the LCs optical appearance. Interestingly, as ACh was also a substrate of AChE, the bright appearance of LCs was prevented when incubating the mixture of AChE and ACh with Myr decorated aqueous/LC interface due to the competitive enzymatic hydrolysis between Myr and ACh by AChE. By using this strategy, ACh could be detected selectively and sensitively, with a broad linear range from 0.01 μmol/L to 1 mmol/L and a low detection limit of 14.5 nmol/L. The results showed that the competitive enzymatic hydrolysis-assisted LC-based sensor had potential applications in ACh detection.

Although lithium (Li) and sodium (Na) metals can be selected as the promising anode materials for next‐generation rechargeable batteries of high energy density, their practical applications are greatly restricted by the uncontrollable dendrite growth. Herein, a platinum (Pt)–copper (Cu) alloy‐coated Cu foam (Pt–Cu foam) is prepared and then used as the substrate for Li and Na metal anodes. Owing to the ultrarough morphology with a three‐dimensional porous structure and the quite large surface area as well as lithiophilicity and sodiophilicity, both Li and Na dendrite growths are significantly suppressed on the substrate. Moreover, during Li plating, the lithiated Pt atoms can dissolve into Li phase, leaving a lot of microsized holes on the substrate. During Na plating, although the sodiated Pt atoms cannot dissolve into Na phase, the sodiation of Pt atoms elevates many microsized blocks above the current collector. Either the holes or the voids on the surface of Pt–Cu foam what can be extra place for deposited alkali metal, what effectively relaxes the internal stress caused by the volume exchange during Li and Na plating/stripping. Therefore, the symmetric batteries of Li@Pt–Cu foam and Na@Pt–Cu foam have both achieved long‐term cycling stability even at ultrahigh areal capacity at 20 mAh cm−2.

Hexavalent chromium is highly toxic and regarded as one of the main pollutants in the environment. Sophisticated laboratory instruments are commercially available for the in-field determination of chromium. It is highly desirable to develop affordable, portable, sensitive and reliable methods for on-site Cr(VI) detection. For field analysis, we designed a smartphone-based absorbance device with an ultralong absorption path to improve sensitivity. The intensity of the transmission light was detected by the illumination sensor in the smartphone. The absorption path was enlarged to a maximum of 83.5 cm by 41 reflection cycles. The intensity of the reflected light in an empty colorimetric cell can be serviced as the internal references to correct the possible baseline drift due to light source intensity decay. The absorbance measured by the proposed device obeys the Lambert–Beer law in the range of 0–1.1. This device was used to determine Cr(VI) in water samples on-site by using 1,5-diphenylcarbazide as a colorimetric reagent, with the linear range of 1–18 μg L−1 and limit of detection of 0.26 μg L−1. This simple absorbance device offers the advantages of cost-effectiveness, ease of implementation, portability, sensitivity and reliability for field analysis.

Two-dimensional (2D) heterostructures with the Z-scheme can significantly improve the recombination of the photogenerated charge pairs and increase the overpotential compared with the corresponding monolayers. Based on first-principles calculations, we demonstrate the photocatalytic performance with the Z-scheme of three 2D AuSe/SnS heterostructures identified from nine stacking types of AuSe and SnS monolayers using their formation energies. The thermal stabilities of the chosen heterostructures are assured by molecular dynamics simulations. The band alignment and built-in electric field support the heterostructures to drive the photocatalytic hydrogen and oxidation evolution reactions with the direct Z-scheme. Moreover, the optical absorption of both AuSe and SnS monolayers is obviously observed in the visible light and UV ranges, indicating their excellent response to solar light. The highest solar-to-hydrogen energy conversion efficiency of the heterostructures can reach 23.96%. The change in Gibbs free energy in the hydrogen evolution reaction with the heterostructures is in the range of 0.63–0.97 eV, indicating that these reactions are not difficult to carry out. Therefore, the present AuSe/SnS heterostructures could be promising candidates for producing hydrogen from photocatalytic water splitting with the Z-scheme driven by solar light.

Benzo[a]pyrene (Bap) is one of the main organic pollutants in the atmospheric haze that is rich in fine water drops and particulate matters. The understanding of the Bap's form in water is of great importance to unveil its real biological effects toward the respiratory system. To date, various reports have documented its toxicological effects in the molecular form. Herein, we found that Bap existed as self-aggregated nanoclusters of tunable sizes rather than as dissolved molecules in water and different sized nanoclusters illustrated varied cytotoxicity. These findings indicated that the size, which has been ignored in previous studies, is also a dominant parameter similar to the molecular concentration for determining Bap's cytotoxicity. Polystyrene (PS) nanoparticles, as a model for nanoplastics, could adsorb Bap nanoclusters and serve as carriers that enter the cells. The combination effect interestingly altered the cytotoxicity distinction of Bap of different sizes. The intracellular fate of the nanoparticles and subcellular organelle damages were studied to unveil the mechanisms of cytotoxic distinction. Small Bap nanoclusters entered cells faster than their large counterparts. The Bap of the PS@Bap complex was stably adsorbed on PS at the early stages of endocytosis until it was detached during the lysosomal transport and maturation process. The dissociated Bap may bypass the lysosome pathway and be released into the cytosol with a nanocluster structure or relocate into the endoplasmic reticulum. On the other hand, the detached PS preferred to bind to the mitochondria or be excreted out of the cell via the lysosomal pathway. Moreover, the PS@Bap complex resulted in a significant loss of the mitochondrial membrane potential and induced apoptosis through the mitochondria-involved apoptosis pathway. This study provides a new perspective towards the toxicological mechanism of insoluble hydrophobic organic compounds and reveals the environmental significance of nanoplastics for regulating the biological effects of conventional pollutants.

Quantification of multiple disease-related microRNAs (miRNAs) is of great significance for clinical diagnosis. Based on the simultaneous multiple element detection ability of inductively coupled plasma-mass spectrometry (ICP-MS) and good specificity of multicomponent nucleic acid enzymes (MNAzymes), a novel and simple method based on the MNAzyme amplification strategy and lanthanide labeling coupled with ICP-MS detection was proposed for the sensitive and simultaneous detection of three miRNAs (miRNA-21, miRNA-155, and miRNA-10b). Specifically, a probe consisting of streptavidin-modified magnetic beads (SA-MBs) and three DNA substrates labeled with lanthanide tags (159Tb/165Ho/175Lu) was constructed. In the presence of target miRNAs, three pairs of MNAzymes were assembled where each pair was hybridized with the corresponding miRNA, and then the substrates on the SA-MBs were cleaved by the activated MNAzymes, continuously releasing the fragment with lanthanide tags. The released lanthanide tags in the supernatant were collected after magnetic separation and analyzed by ICP-MS, realizing the simultaneous quantification of multiple miRNAs. The correlation of the lanthanide tag signal with the miRNA concentration fitted well in a linear model in the range of 50-1000 pmol L-1 (miRNA-21) and 50-2000 pmol L-1 (miRNA-155 and miRNA-10b). The limits of detection for three miRNAs were 11-20 pmol L-1, with the relative standard deviations of 2.2-2.7%. The recoveries of target miRNAs in the human serum and HepG-2 cells were in the range of 87.2-111% and 93.3-111%, respectively. Overall, the method is ideal for the simultaneous quantification of multiple miRNAs with advantages of low spectral interference, high sensitivity, good selectivity, and strong resistance to the complex matrix.

Adenosine triphosphate (ATP), as a high-energy phosphate compound that stores and releases energy in living cells, has an irreplaceable role in many physiological processes and maintenance of biological functions, and can be used as an indicator of many diseases. In this work, a composite nanoprobe, silver nanocluster (AgNC) @ molybdenum disulfide (MoS2), was designed to achieve in situ fluorescence imaging and quantitative analysis of intracellular ATP in HeLa cells by fluorescence spectrometry and inductively coupled plasma mass spectrometry (ICP-MS). The probe was constructed based on the adsorption of DNA-AgNCs by MoS2 nanosheets, and the DNA-AgNCs were prepared with the ATP aptamer as a template, whose fluorescence was initially quenched by MoS2. When the probe was incubated into the cells, intracellular ATP recognized the aptamer sequence and caused the DNA-AgNCs to fall off the MoS2 nanosheets, resulting in fluorescence recovery. Here, AgNCs not only acted as a fluorescence label for imaging, but also as an element tag for quantitative analysis of intracellular ATP with the detection of 107Ag by ICP-MS. The ATP in HeLa cells detected by this method was 24.6 ± 1.7 nmol L−1, which was in good agreement with the test result of the ATP test kit (20.4 ± 0.8 nmol L−1). The proposed method has potential application in medical clinical diagnosis and evaluation of the body’s metabolic level via fluorescence imaging and ICP-MS detection of intracellular ATP.

Molecularly imprinting polymers (MIPs), as artificial antibodies with high recognition selectivity to template molecules, are widely used in various biosensors. To improve further the selectivity of MIPs-based photoelectrochemical (PEC) biosensors, we report a differential strategy using non-imprinted polymers (NIPs) as the reference. In a proof-to-concept example for the determination of dopamine (DA), MIPs and NIPs membranes were fabricated by electrochemical polymerization of polypyrrole membranes on the surface of graphene quantum dots (GQDs)/TiO2 nanotubes (NTs). The photocurrent difference between the two PEC cells, MIPs@GQDs/TiO2 NTs−Pt and NIPs@GQDs/TiO2 NTs−Pt, was measured as the signal. As the non-specific adsorption of non-template molecules on the outside surface of MIPs and NIPs membranes is similar, the anti-interference ability for the determination of DA is much improved by using differential strategy. In the normal and differential PEC measurement models, 10.0 μM ascorbic acid is equivalent to 3.12 and 0.40 μM DA, respectively. Further, the smaller specific surface area in NIPs membrane was compensated by using a weight factor to correct the residual interference in a modified differential model. By using 10.0 μM ascorbic acid as the balance point, the presence of 10.0 μM H2O2, glutathione, uric acid or glucose is equivalent only to 0.090, 0.061,0.11 or 0.041 μM of DA, respectively, which are about 3–7% of their interference levels in the normal photocurrent model. The differential PEC method was applied in the determination of DA in serum samples in the linear range of 0.05–12.5 μM, with the detection limit of 0.018 μM.

Lithium-ion capacitors (LICs) could combine the virtues of high power capability of conventional super-3capacitors and high energy density of lithium-ion batteries. However, the lack of high-performance electrode materials and the kinetic imbalance between the positive and negative electrodes are the major challenge. In this study, Fe3O4 nanoparticles encapsulated in nitrogen-rich carbon (Fe3O4@NC) were prepared through a self-assembly of the colloidal FeOOH with polyaniline (PANI) followed by pyrolysis. Due to the well-designed nanostructure, conductive nitrogen-rich carbon shells, abundant micropores and high specific surface area, Fe3O4@NC-700 delivers a high capacity, high rate capability and long cycling stability. Kinetic analyses of the redox reactions reveal the pseudocapacitive mechanism and the feasibility as negative material in LIC devices. A novel LIC was constructed with Fe3O4@NC-700 as the negative electrode and expanded graphene (EGN) as the positive electrode. The well-matched two electrodes effectively alleviate the kinetic imbalance between the positive and negative electrodes. As a result, Fe3O4@NC-700//EGN LIC exhibits a wide operating voltage window, and thus achieves an ultrahigh energy density of 137.5 W h kg−1. These results provide fundamental insights into the design of pseudocapacitive electrode and show future research directions towards the next generation energy storage devices.

With high energy density and low material cost, lithium-sulfur batteries (LSBs) emerge quite expeditiously as a fascinating energy storage system over the past decade. Broad applications of LSBs ranging from electric vehicles to stationary grid storage seem rather bright in recent literatures. However, there still exist many pressing challenges to be addressed because we do not yet fully understand and control the electrode-electrolyte interface chemistries during battery operation, such as polysulfide shuttling and poor utilization of active sulfur. Single-atom catalysts (SACs) pave new possibilities of tackling the tough issues due to their decent applicability in the atomic-level identification of structure-activity relationships and reaction mechanism, as well as their structural tunability with atomic precision. This review comprehensively summarizes the very recent advances in utilization of highly active SACs for LSBs by stating and discussing the related publications, which involves catalyst synthesis routes, battery performance, catalytic mechanisms, optimization strategies, and promises to achieve long-life, high-energy LSBs. We see that endeavors to employ SACs to modify sulfur cathode have allowed efficient polysulfide conversion and confinement, leading to the minimization of shuttle effect. Parallel efforts are being devoted to extending the scope of SACs to cell separator and lithium metal anode in order to unlock the full potential of LSBs. We also obtain mechanistic insights into battery chemistries and nature of SACs in their strong interactions with polysulfides through advanced in situ characterizations documented. Overall, acceleration in the development of LSBs by introducing SACs is noticeable, and this cutting edge needs more attentions to further promoting the design of better LSBs.

Computational simulation methods are used for characterizing the detailed attachment, diffusion and desorption of halogen vapor molecules in zeolitic imidazolate framework-8 (ZIF-8). The attachment energies of Cl2, Br2 and I2 are −55.2, −48.5 and −43.0 kJ mol−1, respectively. The framework of ZIF-8 is disrupted by Cl2, which bonds with Zn either on the surface or by freely diffusing into the cage. A framework deformation on the surface of ZIF-8 can be caused by the attachment of Br2, but only reorientation of the 2-methylimidazolate linkers (mIms) for I2. In diffusion, the halogen molecules have a tendency to vertically permeate the apertures of cages followed with swing effect implemented by the mIms. Larger rotation angles of mIms are caused by Br2 because of its stronger interaction with mIms than I2. A maximum of 7 Br2 or 5 I2 molecules can be accommodated in one cage. Br2 are clinging to the mIms and I2 are arranged as crystal layout in the cages, therefore in desorption processes molecules attached to the surface and free inside are desorbed while some remained. These results are beneficial for better understanding the adsorption and desorption processes of halogen vapors in the porous materials.

In this work, we report a simple ratiometric electrochemiluminescence (ECL) method for ultra-sensitive immunoanalysis. A glassy carbon electrode (GCE) was modified by a mixture of porous g-C3N4 nanosheets and carbon nanotubes (CNTs). Secondary antibodies were labeled using CuS nanoparticles as the tags. After immune recognition, CuS nanoparticles in the immunocomplex were dissolved as Cu2+, which can quench the ECL of g-C3N4. The amount of Cu2+ was determined to quantify the concentration of the target antigen. To enhance the sensitivity, Cu2+ ions were firstly enriched and reduced to Cu on the surface of GCE/CNTs-g-C3N4, and the cathodic ECL of g-C3N4 was measured as the reference signal in the ratiometric ECL measurements. After applying a potential of 0.6 V (vs. Ag/AgCl) for 6 s, Cu was dissolved as Cu2+, which can quench the ECL of g-C3N4 with much higher efficiency because the freshly dissolved Cu2+ ions were distributed mainly within the Helmholtz layer of GCE/CNTs-g-C3N4. By using the ECL intensity ratio of GCE/CNTs-g-C3N4 (Cu2+) to GCE/CNTs-g-C3N4 (Cu) measured under the potentiostatic model as the signal indictor, the ratiometric ECL method was used to detect a biomarker of alpha fetoprotein with the limit of detection of 0.1 fg mL-1. It was shown that the influence of the difference in electrode modification and ECL measurement conditions on the determination of Cu2+ is suppressed greatly in the ratiometric ECL method. The combination of ratiometric ECL with electrochemical enrichment and biometallization is a useful strategy to enhance the sensitivity and reproducibility in immunoanalysis.

Herein, we demonstrate a simple approach for tuning the elecrochemiluminescence (ECL) properties of CsPbBr3 perovskite nanocrystals (NCs) by using mixed-monovalent cations. By replacing some of the Cs+ with Rb+, a series of RbxCs1−xPbBr3 NCs were obtained. They exhibit a narrow ECL emission peak with a full width at half-maximum of about 26–34 nm. After continuously injecting holes to produce different charged state radicals, an annihilation ECL was observed, implying that the as-prepared RbxCs1−xPbBr3 NCs are in an electron-rich state. In the presence of 2-dibutyaminoethanol as a co-reactant, strong anodic ECL of RbxCs1−xPbBr3 NCs was obtained. From CsPbBr3 NCs to RbPbBr3 NCs, the ECL peak potential position moved from 1.25 V to 1.80 V with the ECL spectrum peak shifting from 512 to 468 nm, respectively, indicating the tunable ECL properties. The Rb0.2Cs0.8PbBr3 NCs have a higher ECL intensity than the CsPbBr3 NCs.

The continuous exploration of advanced electrode materials is of remarkable significance to revolutionize next-generation high-performance energy storage devices towards a green future. Benefiting from their electrochemically active sites and abundant redox centers, bimetallic selenides with desirable nanostructures recently have emerged as promising electrode alternatives for battery–supercapacitor hybrid (BSH) devices which demonstrate enormous potential in bridging the gap between electrochemical properties with high power densities (supercapacitors) and energy densities (batteries). Herein, employing the hydrothermal approach with solid Ni–Co spheres as precursors followed by the selenization process, selenide-rich bimetallic selenide spheres with a core–shell nanostructure were rationally designed and synthesized for use as the cathode electrode in superior BSH devices. The as-obtained (NiCo)9Se8/(NiCo)0.85Se (Ni–Co–Se) exhibits a high specific capacity of 164.44 mA h g−1 at a current density of 1 A g−1 with 85.72% capacity retention even after 5000 cycles at a current density of as high as 8 A g−1, suggesting its great promise in practical applications for BSH devices. By integrating activated carbon as the anode with the as-obtained bimetallic selenides as the cathode, an alkaline aqueous BSH device is fabricated and delivers a high energy density of 37.54 W h kg−1 at a high power density of 842.7 W kg−1. It is found that the excellent electrochemical performances can be ascribed to facile ion and electron transport pathways, high electrical conductivity and reliable structural robustness of the prepared selenides. Moreover, the synthetic strategy presented in this paper opens up an avenue to guide the synthesis of various anion doped bimetallic compounds towards high-performance energy conversion and storage devices.

Most photovoltaic (PV) plants conduct operation and maintenance (O&amp, M) by periodical inspection and cleaning. Such O&amp, M is costly and inefficient. It fails to detect system faults in time, thus causing heavy loss. To ensure their operations are at an ideal state, this work proposes an unsupervised method for intelligent performance evaluation and data-driven fault detection, which enables engineers to check PV panels in time and implement timely maintenance. It classifies monitoring data into three subsets: ideal period A, transition period S, and downturn period B. Based on A and B datasets, we build two non-continuous regression prediction models, which are based on a tree ensemble algorithm and then modified to fit the non-continuous characteristic of PV data. We compare real-time measured power with both upper and lower reference baselines derived from two predictive models. By calculating their threshold ranges, the proposed method achieves the instantaneous performance monitoring of PV power generation and provides failure identification and O&amp, M suggestions to engineers. It has been assessed on a 6.95 MW PV plant. Its evaluation results indicate that it is able to accurately determine different functioning states and detect both direct and indirect faults in a PV system, thereby achieving intelligent data-driven maintenance.

In recent years, the exploration of tumor microenvironment has provided a new approach for tumor treatment. More and more researches are devoted to designing tumor microenvironment-responsive nanogels loaded with therapeutic drugs. Compared with other drug carriers, nanogel has shown great potential in improving the effect of chemotherapy, which is attributed to its stable size, superior hydrophilicity, excellent biocompatibility, and responsiveness to specific environment. This review primarily summarizes the common preparation techniques of nanogels (such as free radical polymerization, covalent cross-linking, and physical self-assembly) and loading ways of drug in nanogels (including physical encapsulation and chemical coupling) as well as the controlled drug release behaviors. Furthermore, the difficulties and prospects of nanogels as drug carriers are also briefly described.

Accumulating evidence insists that circular RNAs (circRNAs) play important roles in the development of human cancers, including gastric cancer. This study aimed to investigate the role of circ-SFMBT2 and provide a potential mechanism to explain its function. The expression of circ-SFMBT2, miR-885-3p and chromodomain-helicase-DNA-binding protein 7 (CHD7) mRNA was determined by quantitative real-time PCR (qRT-PCR), and the protein level of CHD7 was determined by western blot. To investigate the function of circ-SFMBT2 in vitro, the effects of circ-SFMBT2 on cell viability, colony formation, apoptosis, migration and invasion were assessed using cell counting kit-8 assay, colony formation assay, flow cytometry assay, wounding healing assay and transwell assay, respectively. The indicators of oxidative stress were assessed using matched kits. Besides, the function of circ-SFMBT2 was also investigated in animal models. The relationship between miR-885-3p and circ-SFMBT2 or CHD7 was verified by dual-luciferase reporter assay and RNA immunoprecipitation assay. Circ-SFMBT2 and CHD7 were upregulated, whereas miR-885-3p was downregulated in gastric cancer tissues and cells. In functional assay, circ-SFMBT2 knockdown suppressed gastric cancer cell viability, colony formation ability, migration, invasion and oxidative stress but induced apoptosis, and circ-SFMBT2 downregulation also blocked tumor growth in vivo. In mechanism analysis, circ-SFMBT2 regulated CHD7 expression by sponging its target miRNA, miR-885-3p. Rescue experiments manifested that miR-885-3p inhibition reversed the effects of circ-SFMBT2 knockdown, and CHD7 overexpression abolished the antitumor role of miR-885-3p overexpression. Moreover, circ-SFMBT2 knockdown inactivated the Wnt/β-catenin signaling pathway. Circ-SFMBT2 downregulation repressed the development of gastric cancer partially by controlling the miR-885-3p/CHD7 axis, which might be a novel strategy to inhibit gastric cancer progression.

The magnetic resonance imaging diagnosis and high-efficiency tumor targeting treatment are of notable importance for cancer therapy. In this study, starch-octanoic acid (ST-OA) micelles were successfully prepared to co-encapsulate the anti-tumor drug doxorubicin (DOX) and superparamagnetic iron oxide nanoparticles (SPIONs), taking advantage of the hydrophobic core of the core-shell micellar structure. Size distribution, morphology and in vitro release behaviors of micelles were investigated. In addition, magnetic properties and the anti-tumor theranostic performance were confirmed by conducting the cellular uptake, in vivo imaging and anti-tumor activity experiments. Therefore, co-encapsulation and specific delivery of the chemotherapeutic drug and contrast agent into tumor cells can realize the diagnosis and treatment of malignant tumor at the same time.

Detection of biomarkers in body fluids is critical to both diagnosing the life-threatening diseases and optimizing therapeutic interventions. We herein report use of liquid crystals (LCs) to detect biomarkers in blood with high sensitivity and specificity by employing in situ rolling circle amplification (RCA) on magnetic beads (MBs). Specific recognition of cancer biomarkers, such as platelet derived growth factor BB (PDGF-BB) and adenosine, by aptamers leads to formation of a nucleic acid circle on MBs preassembled with ligation DNA, linear padlock DNA, and aptamers, thereby triggering in situ RCA. LCs change from dark to bright appearance after the in situ RCA products being transferred onto the LC interface decorated with octadecy trimethylammonium bromide (OTAB), which is particularly sensitive to the amplified DNA on MBs. Overall, this label-free approach takes advantages of high specificity of aptamer-based assay, efficient enrichment of signaling molecules on MBs, remarkable DNA elongation performance of the RCA reaction, and high sensitivity of LC-based assay. It successfully eliminates the matrix interference on the LC-based sensors and thus achieves at least 4 orders of magnitude improvement in sensitivity for detection of biomarkers compared to other LC-based sensors. In addition, performance of the developed sensor is comparable to that of the commercial ones. Thus, this study provides a simple, powerful, and promising approach to facilitate highly sensitive, specific, and label-free detection of biomarkers in body fluids.

Oxidative stress is an important pathological mechanism for acute kidney injury (AKI). SS-31, as a mitochondria-targeted peptide with strong antioxidant activity, is a good candidate for the treatment of AKI. However, an efficient treatment of AKI requires frequent administration of SS-31, which is due to its poor specific biodistribution and low delivery efficiency. To overcome these deficiencies, we designed pH-responsive and AKI-kidney targeted nanopolyplexes (NPs) for effectively delivering SS-31, which is new frontier for formulation of HA and CS. NPs are electrostatically complexed using anionic hyaluronic acid and cationic chitosan as materials, which could increase the accumulation in injured areas and uptake into CD44-overexpressed cells. Electrostatic balance of NPs is broken in low pH environment of lysosomes to allow SS-31 releasing and subsequently targeting to mitochondria to represent therapeutic effect. In vitro studies indicate that NPs exhibited higher antioxidative and antiapoptotic effects as compared with free SS-31. AKI mouse model suggests that NPs have significantly higher therapeutic efficiency than bare SS-31. It was found that NPs had excellent ability to decrease oxidative stress, protect mitochondrial structure, reduce inflammatory response, reduce apoptosis and necrosis of tubular cells after intravenious administration. Overall, the results suggest that the NPs have significant potential to enhance the specific biodistribution and delivery of SS-31, therefore have good effects on reducing oxidative stress and inflammation, preventing tubular apoptosis and necrosis. We believe NPs are effective delivery system for AKI treatment in clinical application.

Cationic anticancer peptides, which can induce tumor cell immunogenic death and further promote systemic tumor-specific immune responses, have offered a promising solution to relieve the tumor immunosuppressive microenvironment. However, peptide drugs are easily degraded and lack of targeting ability when administered systemically, leading to limitations in their applications. Herein, we report a pH and thermal dual-sensitive bovine lactoferricin-loaded (one of the most widely studied cationic anticancer peptides) nanoparticles, which simultaneously exhibited antitumor and immune cell activated effects when applied with microwave thermotherapy, an auxiliary method of immunotherapy. The bovine lactoferricin could be delivered to the tumor site by nanoparticles, be immediately released from nanoparticles in the acidic environment of lysosomes and the thermal condition caused by microwave radiation, and ultimately induce tumor apoptosis with the release of damage-associated molecular patterns (DAMPs). It is worth noting that the strategy of bovine lactoferricin-loaded nanoparticles intravenous injection combined with local microwave thermotherapy not only showed excellent efficacy in relieving tumor growth but also resulted in strong antitumor immunities, which was due to the released bovine lactoferricin under stimulating conditions, and the pool of tumor-associated antigens generated by tumor destruction. In conclusion, this work presents a strategy for tumor treatment based on dual-sensitive bovine lactoferricin-loaded nanoparticles combined with microwave thermotherapy, which may provide a solution for cationic anticancer peptides delivery and improving antitumor immune responses.

Improvement of the sensitivity and selectivity is important in the development of an analytical method. Herein, we propose a differential photoelectrochemical (PEC) sensor to hydrogen peroxide based on the catalytic activity difference between two zeolitic imidazolate framework (ZIF) surface coatings. In the sensing and reference photoelectrodes, ZIF-67 and ZIF-8 films were grown on the surface of carboxylated carbon nanotubes-graphite-like carbon nitride/TiO2 nanotube array, respectively. The molecular sieve effect of ZIF-8 and ZIF-67 coatings can prevent the diffusion of molecules with size larger than the pores in coating layers (e.g. ascorbic acid), improving the selectivity of the PEC sensor to H2O2. The sensing photoelectrode offers higher sensitivity to H2O2 than the reference one due to the excellent catalytic activity of ZIF-67. The interference from the surfaces of the sensing and reference photoelectrodes can be eliminated effectively by the differential strategy, enhancing further the selectivity, reliability and stability of the sensor. Under optimized conditions, the as-prepared differential PEC sensor was applied to the detection of H2O2 with limit of detection of 1.5 nM, exhibiting high sensitivity and anti-interference ability.

Photodynamic therapy (PDT) and photothermal therapy (PTT) are effective cancer treatments, and photosensitizers play the most important role in the treatment. However, photosensitizers are insufficient for in vivo tumor treatment. Herein, we develop a small molecule fluorophore Cy-HPT as a novel photosensitizer, which possesses the advantages of near-infrared (NIR) emission, high photothermal conversion efficiency and high singlet oxygen generation efficiency. Moreover, a nanoplatform of HSA@Cy-HPT was synthesized by self-assembly of Cy-HPT and human serum albumin (HSA) in aqueous solution. Compared to Cy-HPT, HSA@Cy-HPT possesses more stable spectral properties, enhances the effect of PDT/PTT, and exhibits more satisfactory in vivo metabolism. HSA@Cy-HPT demonstrates outstanding tumor targeting in subcutaneous tumor xenograft models owing to its enhanced permeability and retention in tumor tissue. Furthermore, HSA@Cy-HPT was successfully utilized in tumor xenograft models and tumor tissue growth was clearly inhibited without any regrowth, extending survival rate of the models. Also, no distinct damage of the normal tissue of tumor xenograft models was observed using hematoxylin & eosin staining. This study presents a promising therapeutic agent for the synergetic PDT and PTT cancer treatment.

Multiple drug resistance and the increase in the appearance of superbugs together with the exceedingly scant development of new potent antibiotic drugs pose an urgent global medical threat and imminent public security crisis. In the present study, we fabricated well-dispersed tocopherol polyethylene glycol succinate (TPGS)-capped silver nanoparticles (AgNPs) of about 10 nm in size. The hollow structure of the TPGS-capped AgNPs (TPGS/AgNPs) was confirmed and applied to load antibiotics. The TPGS/AgNPs proved to be able to cross the bacterial cell wall and penetrate into bacteria, thereby delivering more of the antibiotic to the interior of bacteria and thus enhancing the in vitro antibacterial effect of the antibiotic, even overcoming the drug-resistance in drug-resistant E. coli and Acinetobacter baumannii. It was found that the TPGS modification in the TPGS/AgNPs could decrease the activity of the efflux pumps AdeABC and AdeIJK in drug-resistant Acinetobacter baumannii via inhibiting the efflux pump genes adeB and adeJ, thus increasing the accumulation of the delivered antibiotic and overcoming the drug-resistance. Tigecycline delivered by TPGS/AgNPs could effectively antagonize drug-resistance in an acute peritonitis model mice, thereby increasing the survival rate and alleviating the inflammatory response. TPGS/AgNPs were developed as a novel and effective antibiotic delivery system and TPGS was demonstrated to have great potential as a pharmaceutical excipient for use in drug-resistant infection therapy.

A simple, low-cost and label-free strategy for detecting lithocholic acid (LCA) was designed at the liquid crystals (LCs)/aqueous interface via competitive host-guest inclusion. In this method, sodium dodecyl sulfate (SDS) was initially adsorbed on the fluid interface and induced LCs to adopt the homeotropic ordering. Inclusion complexation of SDS and β-cyclodextrin (β-CD) disturbed interaction between LCs and SDS and evoked LCs to keep a tilted alignment. When injecting LCA into the mixed solution of SDS and β-CD, SDS excluded from the cavity of β-CD by competitive host-guest inclusion and could be re-adsorbed at the LCs/aqueous interface, resulting in the orientational transition of LCs from tilted to homeotropic state. Correspondingly, a bright-to-dark optical response was observed under polarized optical microscope (POM). The as-prepared LCs-based sensor could detect LCA as low as about 2 μM in aqueous solution. Moreover, the practicability of the approach was validated by monitoring the known amount of LCA in human urine. This work offers an appealing approach for the detection of LCA which has a great potentiality in clinical diagnosis.

Ratiometric electrochemical sensors can provide a relatively accurate analysis of target analytes due to their self-calibration function. Herein, we report a simple ratiometric strategy for achieving the electrochemical detection of Cd(ii), Hg(ii), Pb(ii) and Zn(ii), as well as multiple cancer biomarkers by using metal sulfide nanoparticles as signal tags. A conductive polymer film of poly(2-amino terephthalic acid) (ATA) was electrochemically produced on a glassy carbon electrode (GCE) and doped with carbon nanotubes (CNTs) and mercaptosuccinic acid (MSA). Using Bi(iii) as an enhancer and internal reference in anodic stripping voltammetry, the MSA-CNT-ATA/GCE exhibited sensitive and distinguishable voltammetric responses to Cd(ii), Hg(ii), Pb(ii) and Zn(ii), with detection limits of 0.13, 0.49, 0.16 and 0.089 μg L-1, respectively. By using CdS, HgS, PbS and ZnS labeled secondary antibodies as the signal tags, alpha-fetoprotein, carbohydrate antigen 19-9, carbohydrate antigen 125, and carcinoembryonic antigen were determined simultaneously according to the amounts of metal sulfide in the sandwich-type complexes, with detection limits of 0.11 pg mL-1, 0.68 mU mL-1, 1.4 mU mL-1 and 0.23 pg mL-1, respectively. This ratiometric approach has a wide scope in the electrochemical detection of heavy metal ions as well as immunoassays with metal ions serving as signal tags.

A liquid crystals (LCs)-based sensing platform was constructed for simple, convenient, inexpensive and label-free detection of α-amylase, associated with disruption of host-guest interaction between sodium dodecyl sulphate (SDS) and β-cyclodextrin (β-CD). In the presence of SDS/β-CD solution, a bright optical image was observed corresponding to the tilted anchoring of LCs at the aqueous/LCs interface. While a black optical appearance was captured when the pre-incubated mixture containing SDS/β-CD complex and ≥0.0001 mg/mL α-amylase was transferred onto the fluid interface. The reason for this difference is that α-amylase could hydrolyze β-CD and subsequently destroy the host-guest interaction between SDS and β-CD. SDS molecules escaping from the cavity of β-CDs were adsorbed at the aqueous/LCs interface, which evoked the homeotropic state of LCs. In the case of α-amylase below 0.0001 mg/mL, a bright optical image was observed. Based on these, detection of α-amylase could be achieved and its detection limit was ∼0.0001 mg/mL (15 U/L). Moreover, this sensing platform was successfully utilized to monitor α-amylase in the body fluids, such as urine and saliva, indicating its potentiality in the relevant clinical diagnosis.

Lithium–sulfur (Li–S) batteries are widely regarded as some of the most promising next-generation energy storage systems due to their cost advantage and high theoretical energy density. However, the shuttle effect arising from the dissolution of polysulfides into organic electrolyte, the insulating nature of sulfur and their discharge products severely restrict the development of high-energy density Li–S batteries. Herein, a porous organic framework containing diketopyrrolopyrrole (DPP) building blocks is reasonably designed and it serves as a shuttle-inhibiting layer to bifunctionally increase the physical and chemical trapping of lithium polysulfides. The frameworks were synthesized through a bottom-up approach, allowing precise control of the network design at the molecular level. As a result, the framework-derived microscale networks with polar units effectively hinder the shuttle effect of polysulfides and promise excellent electrochemical performances with regard to improving kinetics and long-term cycling stability of Li–S batteries. DFT calculations demonstrate the charge transfer (CT) behavior and favorable binding energy between the DPP units and lithium polysulfides. This work not only provides a novel strategy to fabricate a bifunctional modified separator for high-performance Li–S batteries, but also inspires us to further develop advanced materials for emerging energy storage applications.

Effective treatment for acute lung injury (ALI) is in high demand. Lung-targeted ternary nanoparticles containing anti-intercellular adhesion molecule-1 (ICAM-1) antibody-conjugated simvastatin-loaded nanostructured lipid carrier (ICAM/NLC), protamine (Pro), and angiopoietin-1 (Ang-1) gene (ICAM-NLC/Pro/Ang) were developed for ALI therapy. The ternary nanoparticles with different weight ratios of ICAM-NLC to Ang-1 gene were prepared via charge interaction. The anti-ICAM-1 antibody-conjugated ternary nanoparticles exhibited higher cellular uptake and transfection efficiency (from 26.7% to 30.9%) in human vascular endothelial cell line EAhy926 than the non-targeted control. The largest size of ICAM-NLC/Pro/Ang (357.1 nm) was employed for further study, which significantly up-regulated in vitro and in vivo Ang-1 protein expression. In vivo i.v. administration of ICAM-NLC/Pro/Ang (357.1 nm) significantly attenuated pulmonary TNF-α and IL-6 levels, inflammatory cell infiltration, and led to positive histological improvements in lipopolysaccharide-induced ALI mice. Collectively, the ICAM-NLC/Pro/Ang that co-delivered simvastatin and Ang-1 gene may represent a potential treatment modality for ALI.

The prevalence of antibiotic resistance and lack of alternative drugs have posed an increasing threat to public health. Here, we prepared β-Ga2O3:Cr3+ nanoparticles modified with ICAM1-antibody-conjugated TPGS (I-TPGS/Ga2O3) as a novel antibiotic carrier for the treatment of drug-resistant infections. Methods: I-TPGS/Ga2O3 were firstly characterized by measuring particle size, morphology, crystal structure, drug loading capacity, and in vitro drug release behaviors. The in vitro antibacterial activities of I-TPGS/Ga2O3/TIG were evaluated using standard and drug-resistant bacteria. The internalization of I-TPGS/Ga2O3 was observed by fluorescence confocal imaging, and the expression levels of the efflux pump genes of TRKP were analyzed by real-time RT-PCR. In vitro cellular uptake and in vivo biodistribution study were performed to investigate the targeting specificity of I-TPGS/Ga2O3 using HUEVC and acute pneumonia mice, respectively. The in vivo anti-infective efficacy and biosafety of I-TPGS/Ga2O3/TIG were finally evaluated using acute pneumonia mice. Results: It was found that TPGS could down-regulate the over-expression of the efflux pump genes, thus decreasing the efflux pump activity of bacteria. I-TPGS/Ga2O3 with small particle size and uniform distribution facilitated their internalization in bacteria, and the TPGS modification resulted in a significant reduction in the efflux of loaded antibiotics. These properties rendered the encapsulated tigecycline to exert a stronger antibacterial activity both in vitro and in vivo. Additionally, targeted delivery of I-TPGS/Ga2O3 mediated by ICAM1 antibodies contributed to a safe and effective therapy. Conclusion: It is of great value to apply I-TPGS/Ga2O3 as a novel and effective antibiotic delivery system for the treatment of drug-resistant infections.

Glutathione (GSH) is of significance in human pathology due to its many cellular functions. γ-Glutamyl transpeptidase (γ-GT) plays a key role in the balance of GSH by breaking down extracellular GSH. In this study, we proposed a novel strategy for sensitive and selective detection of GSH based on LC sensing platform coupled with its inhibition of γ-GT. The γ-GT cleavable surfactant, dodecyl N-ethanamide N, N, N-trimethylammonium bromide (DAA), was synthesized and utilized to decorate the aqueous/LC interface. A black optical image of LCs was observed due to formation of the self-assembled DAA monolayer at the interface. Subsequently, the optical response of LCs returned to bright appearance after transferring γ-GT to the DAA-laden interface because DAA could be enzymatically hydrolyzed by γ-GT and the monolayer was disrupted. Interestingly, LCs remained dark images after the DAA-decorated interface in contact with the pre-incubated GSH and γ-GT. The detection limit of GSH reached 1 pg/mL, which demonstrates high competitiveness with the current assays. The detection mechanism of GSH was explained by Isothermal titration calorimetry (ITC) measurements and Fourier transform infrared (FTIR) spectroscopy. This work presents an appealing route to achieve ultrasensitive detection of GSH according to its hydrolysis by γ-GT and the as-prepared simple and robust LC-based sensing platform has potentials in the diagnosis of GSH-related diseases (e.g. cancer, liver damage, and malignant neoplasms).

Fabrications and applications of luminescent films have been an interesting and important challenge within the realm of academia and industry. Herein, a novel fluorescence-based strategy for the H2O2 detection has been developed by fabrication of stabilized, thin, transparent, and luminescent films composed of europium-containing polyoxometalates (Eu-POM) and environmentally friendly chitosan (CS) via a facile solution casting approach. In comparison with pure Eu-POM, enhanced fluorescent properties are obtained from the as-prepared Eu-POM/CS films in terms of prolonged fluorescence lifetime and a remarkable fluorescent quenching effect in the presence of hydrogen peroxide (H2O2). The fluorescence intensity of Eu-POM/CS films exhibits a linear correlation in response to the H2O2 concentration over a wide range of 1.1–66 μM, with a detection limit of 0.11 μM. Furthermore, the fluorescent films display a high detection selectivity which are capable of differentiating hydrogen peroxide (H2O2) from the interfering species, such as sugars, l -amino acids, and other metabolites. All these advances towards the development of Eu-POM/CS films open up new applications for luminescent films, but most importantly, they can help in the far-reaching technological implementations of a simple, cost-effective method for the detection of H2O2 in many fields.

The lithium sulfur battery is regarded as a promising energy solution because of its high energy density. However, the insulating nature and large volumetric expansion of sulfur and the high solubility of polysulfides restrict their practical applications. Here carbon nanotube (CNT)-induced yolk–shell carbon nanopolyhedra, with Co–N-doping, is used as host material for sulfur. The CNTs are used to create a conductive network which interweaves each carbon polyhedron and induces the formation of a yolk–shell structure during the sulfur melt-diffusion process due to the “perforation effect”. The CNT-connected Co–N-doped carbon nanopolyhedra containing sulfur yolk–shell structure (S@Co–N–C/CNTs-0.5) can achieve a capacity of 712.2 mAh g–1 at 1675 (1 C) mA g–1 after 300 cycles and 511.8 mAh g–1 at 3350 (2 C) mA g–1. The outstanding performance is attributed to the new paradigm, S@Co–N–C/CNTs-0.5 yolk–shell structure, which creates a conductive network allowing for improved electron transport and convenient ele...

Signal amplification for electrochemiluminescence (ECL) has conventionally been achieved by employing effective matrixes that can accelerate the electrochemical redox processes or carry more electr...

The in vivo bio-behaviors and biosafety of nanoparticles were demonstrated to be closely correlated with particle sizes, which illustrated whether they could be used as the effective drug delivery carriers. Though tumor penetration capabilities of the small pore sized-mesoporous silica nanoparticles (MSNs) were reported to be in a particle size-dependent manner, the size effects of large pore sized-MSNs on the safe and effective cancer resistance treatment, especially at sub-50 nm, were not explicitly evaluated. In this study, we fabricate the 20 nm and 50 nm MSNs, and aim at investigating their difference in tumor accumulation, penetration, retention and toxicity both in vitro and in vivo. Our results showed that these two particle sized-MSNs possessed the excellent tumor penetration capabilities both in resistant human hepatocellular carcinoma cells-cultured spheroids and in the corresponding xenograft mice models, but the 50 nm MSNs seemed to have the better tumor accumulation and retention effects than the 20 nm MSNs. Moreover, the 50 nm MSNs displayed the lower toxicities than the 20 nm MSNs whatever on resistant cancer cell lines or on zebrafish embryos, indicating the greater systematic biosafety. In a word, our data provide the evidence that selection of the large pore-sized MSNs at the appropriate particle size (not the smaller the better) as bio-macromolecule nanocarriers will play a key role in the safe and effective treatment against cancer resistance.

The glucagon receptor (GCGR) is activated by glucagon and is essential for glucose, amino acid, and lipid metabolism of animals. GCGR blockade has been demonstrated to induce hypoglycemia, hyperaminoacidemia, hyperglucagonemia, decreased adiposity, hepatosteatosis, and pancreatic α cells hyperplasia in organisms. However, the mechanism of how GCGR regulates these physiological functions is not yet very clear. In our previous study, we revealed that GCGR regulated metabolic network at transcriptional level by RNA-seq using GCGR mutant zebrafish (gcgr−/−). Here, we further performed whole-organism metabolomics and lipidomics profiling on wild-type and gcgr−/− zebrafish to study the changes of metabolites. We found 107 significantly different metabolites from metabolomics analysis and 87 significantly different lipids from lipidomics analysis. Chemical substance classification and pathway analysis integrated with transcriptomics data both revealed that amino acid metabolism and lipid metabolism were remodeled in gcgr-deficient zebrafish. Similar to other studies, our study showed that gcgr−/− zebrafish exhibited decreased ureagenesis and impaired cholesterol metabolism. More interestingly, we found that the glycerophospholipid metabolism was disrupted, the arachidonic acid metabolism was up-regulated, and the tryptophan metabolism pathway was down-regulated in gcgr−/− zebrafish. Based on the omics data, we further validated our findings by revealing that gcgr−/− zebrafish exhibited dampened melatonin diel rhythmicity and increased locomotor activity. These global omics data provide us a better understanding about the role of GCGR in regulating metabolic network and new insight into GCGR physiological functions.

Alcohol use disorder (AUD) is a chronic, relapsing neurological disease affecting over 11 million individuals around the world. Alcoholics often experience negative affective symptoms such as depression, which promote excessive alcohol consumption and relapse drinking. Likewise, depression is a serious, yet common, mood disorder that can encourage alcohol consumption. However, while this comorbid expression of alcohol use disorder and depression severely worsen patient outcome, many gaps in our knowledge remain and impede the effective and efficient treatment of these two disorders. Recently, the rostromedial tegmental nucleus (RMTg), also known as the tail of the ventral tegmental area, has received increasing attention for its role in both disorders. This chapter focuses on the RMTg and its associations with alcohol and depression. Specifically, we (1) review the various RMTg characteristics associated with alcohol consumption and depression, including afferent and efferent structures, (2) outline how RMTg activity relates to these two diseases, and (3) summarize recent evidence on how the RMTg participates in alcohol withdrawal-induced negative affective symptoms.

Boron nitride nanosheets (BNNSs) have gained significant attraction in energy and environment fields because of their two-dimensional (2D) nature, large band gap and high thermal/mechanical performance. However, the current low production efficiency of high-quality BNNSs is still a bottleneck limiting their applications. Herein, based on sonication-assisted liquid-phase exfoliation, we demonstrated a rapid, high-efficient and scalable production strategy of BNNSs and documented the effects of a spectrum of exfoliation factors (e.g., ultrasonic condition, solvent and bulk material feeding) on the yield of BNNSs. A record of yield of 72.5% was achieved while the exfoliated BNNSs have few-layer and defect-free feature. Thanks to the Lewis acid sites of the boron atoms, the BNNSs can interact with the polysulfide anions in liquid electrolyte and also can facilitate the uniform lithium deposition, which finally endow a lithium-sulfur (Li-S) battery with long life. This work provides a facile and rapid strategy for large scale preparation of high-quality BNNSs, also contributes a long-life strategy for dendrite-free Li-S battery, opens new avenues of BNNSs in energy application.

This study examines the hepatoprotective activity of naringin loaded solid nanoparticles (NRG-SLNs) and compared with free naringin (FNRG) against aflatoxin B1 (AFB1) induced hepatocellular carcinoma. The liver's self-healing ability was studied using a self-recovery group that received no therapy. Following AFB1 therapy, rats were given NRG-SLNs produced using the ion-gelation technique. Histology, serum injury indicators, oxidative stress biomarkers, a pro-inflammatory response biomarker, and tumor indicators were used to evaluate the liver tumor and its responsiveness to therapy. At a dosage of 6.18 mg/kg BW, NRG-SLNs (128 ± 4 nm) provided substantially greater hepatoprotection than free NRG. The actions of NRG-SLNs were equivalent to those of silymarin (SILY), which was given at a dosage of 20 mg/kg BW. The lack of regeneration potential of liver tissue after the damage was verified by the self-recovery group. NRG's efficiency in treating hepatic cancer was increased by using SLN's approach. The increased impact is most likely due to: a) enhanced oral bioavailability, b) the regulated and sustained action of enclosed NRG, and c) a decrease in discomfort and toxicity if any after orally administered. NRG-SLNs may be considered as a therapeutic option for hepatic ailments as effectiveness post-induction of liver carcinoma, is demonstrated presently.

A smartphone-based ratiometric fluorescence device was designed to monitor the reaction kinetic process under vigorous mixing conditions, demonstrated by the hydrolysis of Cs4PbBr6 nanocrystals (NCs). In the presence of trace water, part of Cs4PbBr6 NCs (non-fluorescent) was converted to CsPbBr3 NCs (strong fluorescent). Using anthracene as the reference fluorophore, the brightness ratio of the green (from CsPbBr3 NCs) to blue (from anthracene) components in the fluorescence image which was recorded in situ by the smartphone camera was measured as the signal for kinetic analysis. It was shown that the water-triggered conversion reaction from Cs4PbBr6 NCs to CsPbBr3 NCs follows the pseudo-second-order kinetic model in the early rapid hydrolysis stage (up to 4 min). With increasing water content, the hydrolysis of Cs4PbBr6 NCs is promoted to yield more CsPbBr3 NCs, which was used to determine trace water in n-hexane, dichloromethane, and toluene with detection limits of 0.031, 0.043, and 0.057 μL mL−1, respectively. The device offers the advantages of portability and low cost for rapid field determination of trace water in hydrophobic organic solvents.

The nicotinamide adenine dinucleotide (NAD+) is an important small biomolecule that participates in a variety of physiological functions, and it has been regarded as a potential biomarker for disease diagnosis and a promising target for disease treatment. The conventional methods for NAD+ assay often suffer from complicated procedures, expensive labeling, poor selectivity, and unsatisfactory sensitivity. Herein, we develop a label-free and sensitive method for NAD+ assay based on the integration of a trifunctional split dumbbell probe with ligation-triggered isothermal rolling circle amplification (RCA). We design a trifunctional split dumbbell probe that can act as a probe for NAD+ recognition, a template for RCA reaction, and a substrate for SYBR Green I binding. In the presence of target NAD+, it can serve as a cofactor to active E. coli DNA ligase which subsequently catalyzes the ligation of split dumbbell probe to form a circular template for RCA reaction, generating numerous dumbbell probe amplicons which can be easily and label-free monitored by using SYBR Green I as the fluorescent indicator. Due to the high fidelity of NAD+-dependent ligation and high amplification efficiency of RCA amplification, this method exhibits high sensitivity with a detection limit of 85.6 fM and good selectivity with the capability of discriminating target NAD+ from its analogs. Moreover, this method can be applied for accurate and sensitive detection of NAD+ in complex biological samples and cancer cells, holding great potential in NAD+-related biological researches and clinical diagnosis.

Nanoplastics have recently become a worldwide concern as newly emerging airborne pollutants, which can associate with polycyclic aromatic hydrocarbons (PAHs) and form combined contaminant nanoparticles (CCNPs). After being inhaled in the respiratory system, the CCNPs would first encounter the mucous gel layer being rich in mucin. Herein, polystyrene-benzopyrene (PS@Bap) NPs were prepared as CCNPs model and their interaction with mucin and the resultant biological responses were studied. It was observed that mucin corona stably attached to the CCNPs surface, which significantly altered the fate of the CCNPs in lung epithelial cells (A 549 cell line). The mucin corona would 1) stably adsorbed on PS@Bap at the early stages of endocytosis until degraded during the lysosomal transport and maturation process, 2) delay intracellular trafficking of PS@Bap and the progress of Bap detached from PS, 3) enhance uptake of PS@Bap but reduce the cytotoxicity elicited by PS@Bap, as indicated by cell viability, generation of reactive oxygen species, impairment on mitochondrial function, and further cell apoptosis. In addition, in vivo study also verified the enhanced effect of PS on the development of an acute lung inflammatory response induced by Bap. This study highlights the significance of incorporating the effects of mucin for precisely assessing the respiratory system toxicity of nanoplastics based CCNPs in atmospheric environments.