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A series of N2O2tripodal tetradentate ligands derived from di-/tetra-tert-butyl substituted 2-[bis(2-hydroxybenzyl)aminomethyl]X (X = pyridine and benzimidazole) (H2Ln(n= 1–4)) and 8-[bis(3,5-di-tert-butyl-2-hydroxybenzyl)]aminoquinoline (H2L5) were synthesised through a 4-step reaction scheme involving sequential formylation, reduction, bromination and alkylation. Treatment of H2Ln(n= 1–5) with [WO2Cl2(dme)] (dme = 1,2-dimethoxyethane) in the presence of triethylamine gave the corresponding cis-dioxotungsten(vi) complexes [WO2(Ln)] (n= 1–5). The corresponding molybdenum analogues [MoO2(Ln)] (n= 1–5) were also prepared from the reaction of [MoO2(acac)2] (acac = acetylacetonate) with H2Ln(n= 1–3) or [MoO2Cl2(dme)] (dme = 1,2-dimethoxyethane) with H2Ln(n= 4 and 5). All these compounds were fully characterised by a wide range of spectroscopic methods. The molecular structures of [MoO2(Ln)] (n= 2, 4) and [WO2(L2)] were also confirmed by single-crystal X-ray diffraction analysis. The catalytic activities of [MO2(Ln)] (M = Mo, W; n= 1–4) towards epoxidation of styrene were also examined. [ABSTRACT FROM AUTHOR]

We describe a strategy for dispersing single walled nanotubes (SWNTs) in organic solvents using supramolecular coating with tailor-made, structurally adjustable tripodal porphyrin receptors. These have the ability to recognise SWNTs from DMF–toluene mixtures. HR TEM, TM AFM and SEM measurements showed that the hosts wrap around individual arc-made SWNTs, giving monodispersed composites in DMF which are stable for weeks. The dispersed composites were studied by Raman and fluorescence spectroscopies, including laser scanning confocal microscopy (for aggregates incorporated in cells). These porphyrin hosts encapsulate SWNTs based on π–π type interactions in an analogous manner to those observed by single crystal X-ray diffraction in their C60 complexes. These interactions may be further reinforced by porphyrin–porphyrin stacking. Density functional theory (DFT) calculations predicted the structure of the SWNT : porphyrin host complex or composite formed and the binding energies of tripodal porphyrin hosts in composites with either C60 or SWNT as guests. [ABSTRACT FROM AUTHOR]

Polyimide (PI) coated with atomic layer deposition (ALD) thin films shows promising potential for applications in extreme environments. To achieve a high quality ultrathin ALD coating on the PI surface, Al-doped ALD-TiO 2 (ATO) films were deposited on the alkaline hydrothermally activated PI surfaces. The nucleation and growth of ATO films were studied by XPS monitoring and SEM observation. The incorporation of aluminum introduced additional active sites that acted as a seed layer, promoting the adsorption and growth of titanium oxide. This effectively compensated for the defects in the TiO 2 film, resulting in the formation of a continuously growing conformal film on the PI surface. After 200 ALD cycles, the ATO film deposited on PI exhibits excellent water vapor barrier properties and significant resistance to atomic oxygen (AO) erosion. When exposed to an AO flux of 1.4 × 10 22 atom per cm 2 , the erosion yield of the PI coated with 200 ALD cycles of ATO film was as low as 2.4 × 10 -26 cm 3 per atom, which is two orders less than that of the standard polyimide-ref Kapton® film., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Waterborne polyurethane (WPU) offers many advantages and is widely used in coatings, leathers, adhesives, biomaterials, and other consumer products. However, WPU is highly flammable. Many reactive flame retardants have been developed, but their char formation efficiency is still unsatisfactory, and the melt dripping during combustion has not been effectively suppressed. In this paper, a novel phosphorus-containing flame retardant with dihydroxy groups, (6-((4-hydroxyphenyl)((4-hydroxyphenyl)amino)methyl) dibenzo[ c , e ][1,2]oxaphosphinine 6-oxide) (PHAD), was successfully synthesized and incorporated into WPU molecular chain as a chain extender, thereby synthesizing a series of non-ionic flame-retardant waterborne polyurethane (NFRWPU) emulsions. The chemical structure of NFRWPU was successfully characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance. With the help of a thermogravimetric analyzer, scanning electron microscope and other instruments, some key performance parameters of NFRWPU in applications were investigated, including: physical, mechanical, and thermal stability and flammability. Some important experimental results include: both the particle size and viscosity of the emulsion increase gradually with increasing PHAD content, and when the PHAD content reaches 12%, the average particle size of emulsion increases to 106.6 nm with a viscosity of 89 mPa s; with the addition of PHAD, the tensile strength of NFRWPU initially increased and then decreased, while the elongation at break showed a continuous downward trend. The maximum tensile strength reached 22.63 MPa, and the minimum elongation at break dropped to 1060%; the addition of PHAD improved the thermal stability and flame retardancy of the film, with the highest limiting oxygen index value reaching 25.6% and the maximum carbon residue increasing to 6.5%. All these results indicate that NFRWPU is a promising flame retardant WPU considering the comprehensive performance., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The rapid detection of single nucleotide polymorphisms (SNPs) in the CYP2C19 gene is crucial for precise clopidogrel usage. Quantitative real-time polymerase chain reaction (qPCR), as a powerful amplification tool, has been widely employed for CYP2C19 SNPs detection. However, traditional qPCR suffers from long amplification times and high reagent consumption. To address these challenges, this work presents a microfluidic SNPs detection device based on on-chip qPCR. The device includes a rapid thermal cycling system, an optical detection system, a control system, and a complementary silicon-glass chip for CYP2C19 SNPs detection. Compared to commercial qPCR instruments that take 1 hour for testing, this device completes the test in just 15 minutes (40 PCR cycles). The resulting linearity is similar to that found using commercial qPCR instruments but with higher amplification efficiency. Additionally, compared with other silicon-based qPCR chips, this chip is constructed by using a convenient two-step method and offers low manufacturing costs, which potentially reduces single-test costs to an acceptable level. This makes our chip promising for point-of-care testing (POCT)., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Previous studies have shown that vitamin C (VC), an essential vitamin for the human body, can promote the differentiation of muscle satellite cells (MuSCs) in vitro and play an important role in skeletal muscle post-injury regeneration. However, the molecular mechanism of VC regulating MuSC proliferation has not been elucidated. In this study, the role of VC in promoting MuSC proliferation and its molecular mechanism were explored using cell molecular biology and animal experiments. The results showed that VC accelerates the progress of skeletal muscle post-injury regeneration by promoting MuSC proliferation in vivo . VC can also promote skeletal muscle regeneration in the case of atrophy. Using the C2C12 myoblast murine cell line, we observed that VC also stimulated cell proliferation. In addition, after an in vitro study establishing the occurrence of a physical interaction between VC and Pax7, we observed that VC also upregulated the total and nuclear Pax7 protein levels. This mechanism increased the expression of Myf5 (Myogenic Factor 5), a Pax7 target gene. This study establishes a theoretical foundation for understanding the regulatory mechanisms underlying VC-mediated MuSC proliferation and skeletal muscle regeneration. Moreover, it develops the application of VC in animal muscle nutritional supplements and treatment of skeletal muscle-related diseases.

Cognitive impairment, as a prevalent symptom of nervous system disorders, poses one of the most challenging aspects in the management of brain diseases. Lipids present in the cell membranes of all neurons within the brain and dietary lipids can regulate the cognition and memory function. In recent years, the advancements in gut microbiome research have enabled the exploration of dietary lipids targeting the gut-brain axis as a strategy for regulating cognition. This present review provides an in-depth overview of how lipids modulate cognition via the gut-brain axis depending on metabolic, immune, neural and endocrine pathways. It also comprehensively analyzes the effects of diverse lipids on the gut microbiota and intestinal barrier function, thereby affecting the central nervous system and cognitive capacity. Moreover, comparative analysis of the positive and negative effects is presented between beneficial and detrimental lipids. The former encompass monounsaturated fatty acids, short-chain fatty acids, omega-3 polyunsaturated fatty acids, phospholipids, phytosterols, fungal sterols and bioactive lipid-soluble vitamins, as well as lipid-derived gut metabolites, whereas the latter (detrimental lipids) include medium- or long-chain fatty acids, excessive proportions of n-6 polyunsaturated fatty acids, industrial trans fatty acids, and zoosterols. To sum up, the focus of this review is on how gut-brain communication mediates the impact of dietary lipids on cognitive capacity, providing a novel theoretical foundation for promoting brain cognitive health and scientific lipid consumption patterns.

Lattice thermal conductivity ( κ L ) plays a crucial role in the thermal management of electronic devices. In this study, we systematically investigate the thermal transport properties of monolayer fluorinated graphene using a combination of machine learning-based interatomic potentials and the phonon Boltzmann transport equation. At a temperature of 300 K, we find that the κ L values for chair-configured fluorinated graphene monolayers are 184.24 W m -1 K -1 in the zigzag direction and 205.57 W m -1 K -1 in the armchair direction. For the boat configuration, the κ L values are 120.45 W m -1 K -1 and 64.26 W m -1 K -1 in the respective directions. The disparities in κ L between these two configurations predominantly stem from differences in phonon relaxation times, which can be elucidated by examining the Grüneisen parameters representing the degree of anharmonicity. A more in-depth analysis of bond strengths, as assessed by the crystal orbital Hamiltonian population, reveals that the stronger in-plane CC bonds in chair-configured fluorinated graphene monolayers are the primary contributors to the observed variations in anharmonicity.

A simple N , S -chelated four-coordinated difluoroboron-based emitter is reported with three polymorphs, which emit high contrast green (G), yellow (Y) and red (R) light. Interestingly, the G and R-Crystals show different thermally activated delayed fluorescence (TADF) at 530 nm and 630 nm with a remarkable emission spectral shift of up to 100 nm, while the Y-Crystal exhibits room temperature phosphorescence (RTP) at around 570 nm with a high solid-state quantum yield of 77%. Single crystal analysis and theoretical calculations reveal that different molecular conformations and packing modes lead to distinct triplet exciton conversion channels.

A visible-light-induced photocatalyst-free three-component radical tandem cyclization of N -propargylamine and N -allylbromodifluoroacetamides with the insertion of sulfur dioxide has been developed. Diverse difluoroamidosulfonylated quinolines are obtained in moderate to good yields. This protocol features broad functional group tolerance and high regioselectivity. Moreover, mechanistic studies reveal the involvement of the radical pathway and the formation of an electron donor-acceptor (EDA) complex in this reaction.

Dielectrics of the polymer-matrix composite are considered to present combined advantages from both the polymer matrix and inorganic fillers. However, the breakdown strength, as well as energy density, is not effectively enhanced due to the poor compatibility between the organic and inorganic components. Herein, polymer composites derived from polystyrene (PS) and barium titanate (BTO) are proposed and beneficial interface modification by poly(styrene- co -maleic anhydride) (PS- co -mah) is conducted to improve compatibility between the inorganic filler and polymer matrix. The results show that the BTO@PS- co -mah/PS composites, in which the interfacial layer of PS- co -mah would undergo chemical reactions with the aminated BTO and blend PS matrix with excellent physical compatibility, exhibit enhanced breakdown strength and declined dielectric loss compared with both pure PS and BTO/PS without interfacial modulation. Particularly, the BTO@PS- co -mah/PS composite with 5 wt% filler content indicates optimized performance with an E b of 507 MV m -1 and tan  δ of 0.085%. It is deduced that the deep energy traps introduced by the PS- co -mah layer would weaken the local electric field and suppress the space charge transporting so as to optimize the performance of composites. Consequently, the interfacial-modified BTO@PS- co -mah/PS would present great potential for applications, such as film capacitors., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

With the growing development of film capacitors in various applications, the requirements for polymer dielectrics have increased accordingly. In this work, a series of ester-cotaining polyimide (EPI) dielectrics were designed and fabricated. Futhermore, integrated exploration of experimentation and molecular simulation is proposed to achieve polymer dielectrics with advanced comprehensive performance, as well as to analyze the dielectric mechanism in-depth. The EPIs show superior thermal resistance and dielectric properties. A Weibull breakdown strength of 440-540 MV m -1 , permittivity of 3.52-3.85, dissipation factor of 0.627-0.880% and theoretical energy density of 3.13-4.90 J cm -3 were obtained for the EPIs. The relationship between microscopic parameters and dielectric behavior was investigated in detail. According to the experimental and calculated results, there is close correlation between dipolar moment density ( μ / V vdw ) and dielectric permittivity ( ε r ). It is deduced that the integrated research of experiments and molecular simulation would be an effective strategy to reveal the dielectric mechanism as well as assist in the molecular design of polymer dielectrics., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

Cyanocobalamin (CNCbl, the compound name of Vitamin B12) is the only mineral vitamin that is essential for growth and development and cannot be produced by animals. Some studies have found that CNCbl can promote the proliferation and migration of C2C12 cells, but the mechanism by which it affects muscle development is still unknown. In this study, we elucidated the effect of CNCbl on muscle development and studied its underlying mechanism. CNCbl could promote the differentiation of C2C12 cells and upregulate Acvr1, p-Smad2 and p-Smad3 in the TGF-β signaling pathway in vitro . CD320 (the receptor in cell surface for binding with CNCbl transporter transcobalamin II) inhibition could reduce the uptake of CNCbl and significantly downregulate the expression of differentiation marker proteins MyoG and MYH2. Furthermore, the levels of p-Smad2 and p-Smad3 were also reduced with the inhibition of CD320, even though CNCbl was added to the C2C12 culture medium. In addition, the injection of CNCbl could accelerate the process of mouse muscle injury repair, enlarge the diameter of newly formed myofibers and upregulate the expression of MYH2, PAX7, CD320, Acvr1, p-Smad2 and p-Smad3 in vivo . These results suggest that CNCbl can promote muscle development and may play its role by regulating the expression of Acvr1, p-Smad2 and p-Smad3 related to the TGF-β signaling pathway.

Adjusting the structure of the inorganic components has been proved to be an efficient method for the performance optimization of organic-inorganic hybrid materials. One particular organic ligand can typically form numerous hybrid structures with one inorganic source; however, in most cases, only one thermodynamically stable phase can be obtained, which may not be the one with the best properties. Here, we reported a novel method for modulating the optical properties of antimony halide based organic-inorganic hybrid materials by kinetic control of the synthesis. Under such an approach, the kinetically stable phase can be synthesized, which exhibits significantly improved quantum efficiency compared to the thermodynamically stable phase. This approach provides a new route for the development of high-performance organic-inorganic hybrid materials.

Digital PCR (dPCR) has recently attracted great interest due to its high sensitivity and accuracy. However, the existing dPCR depends on multicolor fluorescent dyes and multiple fluorescent channels to achieve multiplex detection, resulting in increased detection cost and limited detection throughput. Here, we developed a deep learning-based similar color analysis method, namely SCAD, to achieve multiplex dPCR in a single fluorescent channel. As a demonstration, we designed a microwell chip-based diplex dPCR system for detecting two genes ( bla NDM and bla VIM ) with two kinds of green fluorescent probes, whose emission colors are difficult to discriminate by traditional fluorescence intensity-based methods. To verify the possibility of deep learning algorithms to distinguish the similar colors, we first applied t-distributed stochastic neighbor embedding (tSNE) to make a clustering map for the microwells with similar fluorescence. Then, we trained a Vision Transformer (ViT) model on 10 000 microwells with two similar colors and tested it with 262 202 microwells. Lastly, the trained model was proven to have highly accurate classification ability (>98% for both the training set and the test set) and precise quantification ability on both bla NDM and bla VIM (ratio difference <0.10). We envision that the developed SCAD method would significantly expand the detection throughput of dPCR without the need for other auxiliary equipment.

Sulphate and dissolved organic matter (DOM) in freshwater systems may regulate the formation of methylmercury (MeHg), a potent neurotoxin that biomagnifies in aquatic ecosystems. While many boreal lakes continue to recover from decades of elevated atmospheric sulphate deposition, little research has examined whether historically high sulphate concentrations can result in persistently elevated MeHg production and accumulation in aquatic systems. This study used sediment from a historically sulphate-impacted lake and an adjacent reference lake in northwestern Ontario, Canada to investigate the legacy effects of sulphate pollution, as well as the effects of newly added sulphate, natural organic matter (NOM) of varying sulphur content and a sulphate reducing bacteria (SRB) inhibitor on enhancing or inhibiting the Hg methylation and demethylation activity ( K meth and K demeth ) in the sediment. We found that K meth and MeHg concentrations in sulphate-impacted lake sediment were significantly greater than in reference lake sediment. Further adding sulphate or NOM with different sulphur content to sediment of both lakes did not significantly change K meth . The addition of a SRB inhibitor resulted in lower K meth only in sulphate-impacted sediment, but methylation was not entirely depressed. Methylmercury demethylation potentials in sediment were consistent across lakes and experimental treatments, except for some impacts related to SRB inhibitor additions in the reference lake sediment. Overall, a broader community of microbes beyond SRB may be methylating Hg and demethylating MeHg in this system. This study reveals that legacies of sulphate pollution in boreal lakes may persist for decades in stimulating elevated Hg methylation in sediment.

A visible-light-induced photocatalytic strategy for the synthesis of flavonoids has been developed through the deoxygenative/cyclization reaction of salicylic acid derivatives with aryl acetylene using diphenyl sulfide as an O-transfer reagent. Based on the controlled experiments, the mechanism of visible-light-induced free radical coupling cyclization was proposed. The protocol obtained 51 flavonoids in good yields and has been successfully applied to the synthesis of some natural flavones.

By randomly pinning particles in fluidized states and finding the local energy minima, we form static packings of mono-disperse disks that resemble random close packing, when only n c = 2.6% of the particles are pinned. The packings are isostatic and exhibit typical critical scalings of the jamming transition. The non-triviality of n c is manifested mainly in two aspects. First, n c acts as a critical point, leading to bifurcated critical scalings in its vicinity. The criticality of n c is also demonstrated in the packings of weakly polydisperse disks. Second, n c sets a length scale in agreement with the characteristic length of random close packing. With robust evidence, we show that this agreement is generally true for both mono- and poly-disperse particles and in both two and three dimensions. The randomness inherited from fluidized states by random pinning thus interprets the randomness of random close packing from a unique perspective.

Sargassum fusiforme fucoidan (SFF) is a highly sulfated heteropolysaccharide with various biological activities. As one of the causative factors of type 2 diabetes mellitus (T2DM), insulin resistance has become a global health issue. In this study, we investigated the potential pharmacological mechanisms by which SFF ameliorates insulin resistance in high-fat diet (HFD)-fed mice. SFF significantly enhanced tauroursodeoxycholic acid (TUDCA, a conjugated bile acid) levels and inhibited the farnesoid X receptor (FXR) signaling in the colon. SFF administration reduced ceramide levels in both serum and colonic tissue of HFD-fed mice, as well as reduced expression of SPT and CerS genes, which encode enzymes crucial to the biosynthesis of ceramides regulated by FXR signaling. Pearson's analysis showed that the TUDCA level was positively correlated with the gut bacteria Clostridium , and this was further validated in pseudo-germfree mice. Taken together, the results suggested that SFF increased TUDCA levels by remodeling gut microbiota, and TUDCA, a natural FXR antagonist, inhibited the FXR/SHP signaling pathway to reduce colon-derived biosynthesis of ceramide, thereby improving insulin resistance in the diet-induced obese (DIO) mice. This study has provided new insights into the therapeutic potential of S. fusiforme fucoidan in metabolic diseases.

A highly sensitive ELISA is critical for early diagnosis and biomarker discovery of various diseases. Although various ELISA technologies have been developed with high sensitivity, they are limited by poor repeatability, high cost, the dependence on complex equipment and/or a prolonged reaction time. To this end, we developed a fast and ultrasensitive ELISA (termed RELISA) based on rolling circle amplification (RCA) and enzymatic signal amplification. The RELISA is established on the traditional ELISA, with only one more RCA step that can be accomplished within 10 minutes. The prolonged single strand DNA (ssDNA) from RCA is able to enrich abundant horseradish peroxidase conjugate (HRP) modified detection probes. Consequently, the intensive HRP is able to catalyze TMB-H 2 O 2 to produce significantly enhanced colorimetric signals. With CEACAM-7 as a model biomarker, the RELISA achieves the limit of detection as low as 2.82 pg mL -1 , which is ∼50 times higher than that of the traditional ELISA. Therefore, we envision that the developed RELISA would be a powerful tool for the early diagnosis of various major diseases.

Type 2 diabetic mellitus (T2DM) is a complicated metabolic disorder that is now considered as a major global public health problem. Fucoidan exhibits diverse biological activities, especially prevention of metabolic diseases. In this regard, we herein aimed to reveal the beneficial effect of Sargassum fusiforme fucoidan (SFF) on high-fat diet (HFD) and streptozotocin (STZ) induced T2DM mice. We noted that on the one hand, SFF significantly decreased fasting blood glucose, diet and water intake, and hyperlipidemia, while on the other hand, it improved glucose tolerance. Furthermore, SFF reduced epididymal fat deposition, attenuated the pathological changes in heart and liver tissues, and decreased oxidative stress in diabetic mice. To explore the underlying mechanisms of these ameliorative effects, the gut microbiota was analyzed. Notably, SFF highly enriched benign microbes including Bacteroides, Faecalibacterium and Blautia, as well as increased levels of (R)-carnitine and choline in the colon of diabetic mice. This may be a potential mechanism for alleviating T2DM, thus implying the benefits of SFF as an adjuvant agent for T2DM treatment. Taken together, this study demonstrated a promising application of fucoidan as one of the adjuvant agents for the management of T2DM in the future.

A highly efficient and versatile method for construction of peptide macrocycles via palladium-catalyzed intramolecular S -arylation of alkyl and aryl thiols with aryl iodides under mild conditions is developed. The method exhibits a broad substrate scope for thiols, aryl iodides and amino acid units. Peptide macrocycles of a wide range of size and composition can be readily assembled in high yield from various easily accessible building blocks. This method has been successfully employed to prepare an 8-million-membered tetrameric cyclic peptide DNA-encoded library (DEL). Preliminary screening of the DEL library against protein p300 identified compounds with single digit micromolar inhibition activity., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

Biological neurons exhibit dynamic excitation behavior in the form of stochastic firing, rather than stiffly giving out spikes upon reaching a fixed threshold voltage, which empowers the brain to perform probabilistic inference in the face of uncertainty. However, owing to the complexity of the stochastic firing process in biological neurons, the challenge of fabricating and applying stochastic neurons with bio-realistic dynamics to probabilistic scenarios remains to be fully addressed. In this work, a novel CuS/GeSe conductive-bridge threshold switching memristor is fabricated and singled out to realize electronic stochastic neurons, which is ascribed to the similarity between the stochastic switching behavior observed in the device and that of biological ion channels. The corresponding electric circuit of a stochastic neuron is then constructed and the probabilistic firing capacity of the neuron is utilized to implement Bayesian inference in a spiking neural network (SNN). The application prospects are demonstrated on the example of a tumor diagnosis task, where common fatal diagnostic errors of a conventional artificial neural network are successfully circumvented. Moreover, in comparison to deterministic neuron-based SNNs, the stochastic neurons enable SNNs to deliver an estimate of the uncertainty in their predictions, and the fidelity of the judgement is drastically improved by 81.2%.

A new hybrid organic-inorganic film, tincone, was developed by using molecular layer deposition (MLD), and exhibited high electrochemical activity toward Li storage. The self-limiting growth behavior, high uniformity on various substrates and good Li-storage performance make tincone a very promising new anode material for 3D microbatteries.

The fabrication of a Z -scheme heterojunction photocatalyst can effectively modulate the electron transfer and separation of photoinduced charge carriers to enhance photocatalytic performance. Here, we demonstrate a direct Z -scheme BiOCl-phosphotungstic acid (BiOCl-HPW) heterojunction, fabricated via a one-step hydrothermal synthesis, as a highly active and stable photocatalyst for the photodegradation of tetracycline. BiOCl-HPWs result in a dramatic improvement in visible-light utilization and photogenerated e - and h + separation, as well as a decrease in the electrical resistance by the addition of HPW. Notably, the BiOCl-HPW heterojunction with optimized phosphotungstic acid (HPW) content achieved an outstanding photodegradation rate of tetracycline (0.0195 min -1 ). A reasonable Z -scheme photocatalytic mechanism based on the analysis of band structure and monitoring of active radicals is proposed. This study highlights the potential implications of the BiOCl-HPW heterojunctions in the photodegradation of other toxic chemicals and photocatalytic studies., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Sargassum fusiforme is a type of brown algae and well known as a longevity promoting vegetable in Northeastern Asia. The polysaccharides derived from Sargassum fusiforme (SFPs) have been suggested as an antioxidant component for anti-aging function. However, global molecular changes in vivo by SFPs have not been fully elucidated. Here, we present a proteomics study using liver tissues of aged male mice that were fed with SFPs. Of forty-nine protein spots, thirty-eight were up-regulated and eleven were down-regulated, showing significant changes in abundance by two-dimensional gel electrophoresis. These differentially expressed proteins were mainly involved in oxidation-reduction, amino acid metabolism, and energy metabolism. Forty-six proteins were integrated into a unified network, with catalase (Cat) at the center. Intriguingly, most of the proteins were speculated as mitochondrial-located proteins. Our findings suggested that SFPs modulated antioxidant enzymes to scavenge redundant free radicals, thus preventing oxidative damage. In conclusion, our study provides a proteomic view on how SFPs have beneficial effects on the aspects of antioxidant and energy metabolism during the aging process. This study facilitates the understanding of anti-aging molecular mechanisms in polysaccharides derived from Sargassum fusiforme.

Mn(iv)-Based nanoparticles (NPs) are effective in improving tumor oxygenation (hypoxia) and reducing endogenous hydrogen peroxide and acidity in the tumor region. However, the optimized reduction conditions of conventional Mn(iv)-based NPs are generally reported at pH ≤ 6.5, while the usual pH range of the tumor microenvironment (TME) is 6.5-7.0. The dissatisfactory imaging performance in the weakly acidic environment may limit their further application in tumor diagnosis. In this study, Mn(iii) was introduced in a nanoplatform, because it is reduced into Mn(ii) in weakly acidic environments. Arg-Gly-Asp (RGD) peptide-decorated bovine serum albumin (BSA) was employed as the stabilizer and scaffold to fabricate Mn(iii)- and Mn(iv)-integrated nanocomposites (RGD-BMnNPs) with suitable size, good stability, and excellent biocompatibility. The as-prepared NPs showed clear contrast enhancement at pH 6.5-6.9 in vitro as well as sensitive and rapid T 1 -weighted imaging performance within the tumor region in a glioblastoma (U87MG) orthotopic model, owing to the intrinsic disproportionation reaction of Mn(iii) in the weakly acidic environment. In addition, these NPs could be used for efficient siRNA delivery. They showed superior advantages in this process, including increased tumour uptake, improved tumor accumulation and enhanced therapeutic effects with the modulation of the TME. These novel albumin-stabilized manganese-based NPs combined with efficient drug delivery capacity hold great potential to serve as intelligent theranostic agents for further clinical translation.

The development of drug delivery systems based on external stimuli-responsive nanocarriers is important to overcome multidrug resistance in breast cancer cells. Herein, iron oxide/gold (Fe3O4/Au) nanoparticles were first fabricated via a simple hydrothermal reaction, and subsequently loaded into porous silicon nanoparticles (PSiNPs) via electrostatic interactions to construct PSiNPs@(Fe3O4/Au) nanocomposites. The as-prepared PSiNPs@(Fe3O4/Au) nanocomposites exhibited excellent super-paramagnetism, photothermal effect, and T2-weight magnetic resonance imaging capability. In particular, with the help of a magnetic field, the cellular uptake of PSiNPs@(Fe3O4/Au) nanocomposites was significantly enhanced in drug-resistant breast cancer cells. Moreover, PSiNPs@(Fe3O4/Au) nanocomposites as carriers showed a high loading and NIR light-triggered release of anticancer drugs. Based on the synergistic effect of magnetic field-enhanced cellular uptake and NIR light-triggered intracellular release, the amount of anticancer drug carried by PSiNPs@(Fe3O4/Au) nanocarriers into the nuclei of drug-resistant breast cancer cells sharply increased, accompanied by improved chemo-photothermal therapeutic efficacy. Finally, PSiNPs@(Fe3O4/Au) nanocomposites under the combined conditions of magnetic field attraction and NIR light irradiation also showed improved anticancer drug penetration and accumulation in three-dimensional multicellular spheroids composed of drug-resistant breast cancer cells, leading to a better growth inhibition effect. Overall, the fabricated PSiNPs@(Fe3O4/Au) nanocomposites demonstrated great potential for the therapy of multidrug-resistant breast cancer in future.

Accurately quantifying hepatitis B virus DNA (HBV-DNA) in serum is important in dynamic monitoring and prognosis evaluation for patients with hepatitis B. Routine assays based on real-time polymerase chain reaction (qPCR) for HBV-DNA quantification usually require laborious calibration curves and may bring bias from the biological samples. To enable absolute quantification of HBV-DNA in a single tube, we described a modification of the conventional Q-Invader assay by separately encoding targeted DNA and artificially designed internal quantitative-standard DNA (QS-DNA) at the flaps of the corresponding downstream probes. Quantification of targeted HBV-DNA was readily achieved by the difference in the quantification cycle value (Ct) between itself and QS-DNA. Furthermore, spiked-in QS-DNA before DNA extraction allowed errors caused by DNA extraction to be corrected. Two different gene regions covering eight genotypes were encoded with the same flap to avoid false-negative results. The method demonstrates a high sensitivity, which enables accurate detection of as low as 2 copies of the HBV-DNA plasmid or 20 IU mL -1 HBV-DNA in serum in a single tube. Successful quantification of 50 clinical samples indicates that our method is cost-effective, labor-saving and reproducible, and promising for the ultra-sensitive quantification analysis of many types of pathogens other than HBV.

Cerium oxide nanoparticles (CeNPs) have been shown to exhibit antioxidant capabilities, but their efficiency in scavenging reactive oxygen species (ROS) and the underlying mechanisms are not yet well understood. In this study, cerium dioxide nanoparticles (CeNPs) and nanorods (CeNRs) were found to exhibit much stronger scavenging activity than ·OH generation in phosphate buffered saline (PBS) and surrogate lung fluid (SLF). The larger surface area and higher defect density of CeNRs may lead to higher ·OH scavenging activity than for CeNPs. These insights are important to understand the redox activity of cerium nanomaterials and provide clues to the role of CeNPs in biological and environmental processes., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The thermal conductivities of GeTe/Bi 2 Te 3 superlattice-like materials are calculated based on density functional perturbation theory (DFPT) and measured using a 3ω method. The calculated results show that the lattice thermal conductivity or thermal diffusivity of GeTe/Bi 2 Te 3 superlattice-like materials significantly decrease due to the effects of interfaces and Bi atoms in Bi 2 Te 3 . Our measured results are in line with the theoretical calculations, and reach an extremely low thermal conductivity at 0.162 W mK -1 compared with published work on Ge-Sb(Bi)-Te, indicating the effectiveness of modulating the thermal properties of phase change materials by using Bi-based GeTe/Bi 2 Te 3 superlattice-like materials. Our findings give a calculation method to modify the thermal characteristics of superlattice-like materials and confirm Bi-based GeTe/Bi 2 Te 3 superlattice-like materials as promising candidates for phase change materials with lower thermal conductivity., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The thermal stability of the amorphous phase is a key property of phase-change memory, which limits the data retention time and device reliability. The high thermal stability of memory devices enables their applications in harsh environments and under extreme conditions. Here, we discovered that the alloying of C, Si and Ge significantly improves the stability of amorphous Sb by adding "alien" tetrahedral seeds to the octahedral matrix. This doping strategy impedes the crystallization at elevated temperatures so that the crystallization temperature of Sb is increased by 170-220 °C. The mechanism is systematically investigated by ab initio molecular dynamics simulations and classical crystal growth theory. We confirm that the alien tetrahedral bonds increase the activation energy of atomic migration upon crystallization. Our results demonstrate an effective alloying strategy to improve the thermal stability of phase change memory, paving the way for the design of durable memory devices.

A facile and efficient strategy is described in this communication for preparing a molecular catalyst/semiconductor hybrid photoanode by immobilizing a cobalt cubane water oxidation catalyst onto a porous BiVO4 electrode via electrochemical polymerization. With the introduction of Vpa as the anchoring linkage, the poly-1/Vpa/Al2O3/BiVO4 photoanode exhibits high performance as well as stability for photoelectrochemical water oxidation.

To understand the influence of the construction of pH-responsive glycopolymer carriers on loading and release behaviors of the drug, three types of block glycopolymers with similar compositions but different constructions, PEG- b -P(DEA- co -GAMA), PEG- b -PDEA- b -PGAMA and PEG- b -PGAMA- b -PDEA, were successfully synthesized via atom transfer radical polymerization (ATRP) method. The compositions and structures of the three glycopolymers were characterized using 1 H NMR (nuclear magnetic resonance) and GPC (gel permeation chromatography), while the morphology and size of aggregates from pH-sensitive block glycopolymers were measured using TEM (transmission electron microscopy) and DLS (dynamic light scattering). The results indicated that the micelles prepared from PEG- b -PGAMA- b -PDEA had a more compact shell structure. The drug-loaded micelles were prepared using the diafiltration method at pH 10, and the loading content and loading efficiency were analyzed using a UV-visible spectrophotometer. DOX-loaded micelles formed by PEG- b -PGAMA- b -PDEA with the more compact shell construction showed the highest loading content and loading efficiency (12.0 wt% and 58.0%) compared with the other two micelles. Moreover, the DOX release tests of these micelles were carried out under two PBS conditions (pH 7.4 and pH 5.5), and the DOX release amount in a certain time was analyzed using a UV-visible spectrophotometer. The results showed that the more compact shell construction of the three layered micelle obstructed the diffusion of a proton into the PDEA core at pH 5.5 and delayed the drug from releasing under both conditions. Moreover the two-layered micelle with a PDEA and PGAMA mixed core showed a relatively high release amount owing to the porous core permitting unimpeded releasing at pH 7.4 and promoted the protonation of PDEA at pH 5.5. Insights gained from this study show that the structure of block copolymers, leading to different constructions of micelles, could adjust the drug loading and release behavior to certain extent, thus it may contribute to improving the design of desirable drug delivery systems., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Constructing heterojunctions by coupling dissimilar semiconductors is a promising approach to boost charge separation and charge transfer in photoelectrochemical (PEC) water splitting. In this work, we fabricated a highly efficient TiO 2 /BiVO 4 heterojunction photoanode for PEC water oxidation via a simple hydrothermal method. The resulting heterojunction photoanodes show enhanced PEC performance compared to the bare BiVO 4 due to the simultaneous improvements in charge separation and charge transfer. Under simulated sunlight illumination (AM 1.5G, 100 mW cm -2 ), a high photocurrent of 3.3 mA cm -2 was obtained at 1.23 V ( vs. the reversible hydrogen electrode (RHE)) in a neutral solution, which exceeds those attained by the previously reported TiO 2 /BiVO 4 heterojunctions. When a molecular Co-cubane catalyst was immobilized onto the electrode, the performance of the TiO 2 /BiVO 4 heterojunction photoanode can be further improved, achieving a higher photocurrent density of 4.6 mA cm -2 at 1.23 V, an almost three-fold enhancement over that of the bare BiVO 4 . These results engender a promising route to designing an efficient photoelectrode for PEC water splitting., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Near-infrared II fluorescence imaging holds great promise for in vivo imaging and imaging-guided surgery with deep penetration and high spatiotemporal resolution. However, most NIR-II aromatic luminophores suffer from the notorious aggregation-caused quenching (ACQ) effect in the aqueous solution, which largely hinders their biomedical application in vivo . In this study, the first NIR-II organic aggregation-induced emission (AIE) fluorophore ( HLZ-BTED ), encapsulated as nanoparticles ( HLZ-BTED dots) for in vivo biomedical imaging, was designed and synthesized. The NIR-II AIE HLZ-BTED dots showed high temporal resolution, high photostability, outstanding water-solubility and biocompatibility in vitro and in vivo . The HLZ-BTED dots were further used for long-term breast tumor imaging and visualizing tumor-feeding blood vessels, long-term hind limb vasculature and incomplete hind limb ischemia. More importantly, as a proof-of-concept, this is the first time that non-invasive and real-time NIR-II imaging of the gastrointestinal tract in health and disease has been performed, making the AIE dots a promising tool for gastrointestinal (GI) tract research, such as understanding the healthy status of GI peristalsis, diagnosing and evaluating intestinal motility dysfunction, and assessing drug effects on intestinal obstruction.

Herein, a simple two-photon turn-on fluorescent probe, N -(6-acyl-2-naphthayl)-maleimide (1), based on a dual PeT/ICT quenching mechanism is reported for the highly sensitive and selective detection of cysteine (Cys) over other biothiols. The probe was applied in the two-photon imaging of Cys in cultured HeLa cells, excited by a near-infrared laser at 690 nm., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The atomically controlled transition of nanohybrids and their effects on charge-carrier dynamics are highly desirable for fundamental studies in photocatalysis. Herein, for the first time, a method combining atomic monodispersity and single-atom alloy was used to prepare a new form of highly efficient silver-based cocatalysts (Ag 25 & Pt 1 Ag 24 ) on graphitic carbon nitride, representing a novel photocatalytic system for hydrogen evolution.

We reported a new approach to achieve enhanced selectivity with a drastic turn-on fluorescence response for the detection of Cys through dual intramolecular cyclization processes and dual PET and ICT quenching mechanisms by the incorporation of an acrylate and a maleimide group onto two opposite sides of a single coumarin fluorophore.

A programmed supramolecular nanocarrier was developed for multistage targeted photodynamic therapy. This smart nanocarrier exhibited enhanced cellular uptake and controlled mitochondria targeting, as well as an excellent photodynamic therapeutic effect after light irradiation.

We describe a technique to measure the viscosity of stably levitated single micron-sized aerosol particles. Particle levitation allows the aerosol phase to be probed in the absence of potentially artefact-causing surfaces. To achieve this feat, we combined two laser based techniques: optical trapping for aerosol particle levitation, using a counter-propagating laser beam configuration, and fluorescent lifetime imaging microscopy (FLIM) of molecular rotors for the measurement of viscosity within the particle. Unlike other techniques used to measure aerosol particle viscosity, this allows for the non-destructive probing of viscosity of aerosol particles without interference from surfaces. The well-described viscosity of sucrose aerosol, under a range of relative humidity conditions, is used to validate the technique. Furthermore we investigate a pharmaceutically-relevant mixture of sodium chloride and salbutamol sulphate under humidities representative of in vivo drug inhalation. Finally, we provide a methodology for incorporating molecular rotors into already levitated particles, thereby making the FLIM/optical trapping technique applicable to real world aerosol systems, such as atmospheric aerosols and those generated by pharmaceutical inhalers.

A triptycene-coumarin hybrid dye DCT-1 with a 1,4-dimethoxybenzene group as the electron donor and a coumarin fluorophore as the acceptor on the separated fins of a triptycene was synthesized. DCT-1 features a charge separated excited state with emissions sensitive to solvent polarities. Moreover, DCT-1 also exhibits aggregation-induced emission properties in water with excellent photostability and pH-stability for potential cell imaging applications.

Novel 5-aminolevulinic acid (ALA) pseudopolyrotaxane prodrug micelles with dual pH-responsive properties were prepared by the host-guest interaction of α-cyclodextrin (α-CD) and poly(ethylene glycol) (PEG). The micelles exhibited pH dependent cellular uptake and pH-sensitive ALA release, enabling enhanced photodynamic therapy.

As the most prevalent preservative worldwide for many years, pentachlorophenol (PCP) has attracted much interest in the study of biodegradation in soil and aquatic ecosystems. However, the key microorganisms involved in anaerobic degradation are less well understood. Hence, we used DNA-based stable isotope probing (SIP) to identify the PCP-degrading microorganisms in iron-rich paddy soil under anaerobic conditions. (12)C- and (13)C-labeled PCP were almost completely degraded in 30 days under iron-reducing conditions. The results of terminal restriction fragment length polymorphism (T-RFLP) of 16S rRNA genes showed that 197 and 217 bp (HaeIII digests) restriction fragments (T-RFs) were enriched in heavy DNA fractions of (13)C-labeled samples, and the information from 16S rRNA gene clone libraries suggested that the microorganisms corresponding to these T-RF fragments, which increased in relative abundance during incubation, belonged to the order of Burkholderiales, in which 197 and 217 bp were classified as unclassified Burkholderiales and the genus Achromobacter, respectively. The results of the present study indicated that Burkholderiales-affiliated microorganisms were responsible for PCP degradation in anaerobic paddy soil and shed new light on in situ bioremediation in anaerobic PCP contaminated soil.

A nucleic acid amplification technique termed as netlike rolling circle amplification is proposed by introducing a nicking enzyme into the existing hyperbranched rolling circle amplification system. Surprisingly dense and uniform network morphology is observed; and cubic amplification is achieved for the sensitive detection of a sequence from HIV.

There is renewed interest in the origin and makeup of ferromanganese nodules (FMNs), long known to soil mineralogists as unusual secondary minerals. However, new evidence suggests that microorganisms play a significant role in the generation of FMNs. The biogenic origin of nodules has remained elusive because until recently, little has been known about the overall microbial community structure in their microbiota. To learn more about the microbial community and to determine the relative abundance, diversity, and composition of the microbial communities present in FMNs and their surrounding soil, we used pyrosequencing to investigate 16S rRNA genes obtained from vertical soil profiles of both paddy fields and sugarcane fields. Using pyrotaq 16S rRNA gene sequencing, we show that the microbial phylogenetic diversity of nodules was higher than those reported in previous studies of this biosphere, and we identified many previously unidentified microorganisms. Here, we show that the microbial community of these nodules is dominated by Burkholderiales, Rhodocyclales, Acidobacteriales, Desulfuromonales, and Clostridiales, and there were no statistically significant differences found when comparing the microbial community structures of FMNs obtained from vertical soil sequences. Although the microbial composition was markedly different between the surrounding soil and the FMNs, the microbes found within the FMNs were very similar to other FMNs from both field types examined here. In addition to their geochemical properties and the microbial community composition of FMNs, we found that the levels of iron (Fe), manganese (Mn), and SiO2 greatly impact the microbial diversity among FMN communities. Our results indicate that the FMN microbial communities from different land-use types are very similar and suggest that natural selection of these microbes is based on the oligotrophic conditions and the high metal content. Researching FMNs in these two land-use patterns, which represent two different redox potentials, deepens our understanding of Fe-Mn biogeochemical cycling in these oligotrophic biospheres and suggests a biogenetical origin for these nodules.

A new approach has been illustrated for the development of stable, efficient, and environmentally "friendly" white phosphorescent materials. Under mild conditions, a new one-dimensional coordination polymer has been prepared from benzo-18-crown-6 with CuI in the presence of KI, which is capable of emitting direct white light in the solid state.

Ascites is a major problem for both human health and animal production, due to its association with high rates of morbidity and mortality, low efficiency of nutrient utilization, and permanent adverse effects on performance. Although it is one of the three major metabolic diseases in poultry production, the underlying mechanisms are largely unknown. In this study, six ascites syndrome (AS) chickens and six normal chickens were obtained from each group (108 chickens) at 21 and 35 days. A liver metabolomics method based on ultra-performance liquid chromatography/quadruple time-of-flight mass spectrometry (UPLC/Q-TOF/MS) was used to explore the metabolic pattern of low molecular mass metabolites in chickens with low-temperature-induced AS. Coupled with blood biochemistry and histopathology results, the significant difference in metabolic profiling between the AS group and the control group, as determined through pattern recognition analysis, indicated changes in global tissue metabolites. The results showed that a primary bile acid synthesis disorder and inflammation had occurred by 21 days and that lysophospholipid metabolism was disrupted by 35 days with the continuation of low temperatures. Several metabolites, including taurodeoxycholic acid, cholic acid glucuronide, glycocholic acid, LysoPC(15 : 0) and taurocholic acid, were identified as the potential and proper biomarkers of AS. These biochemical changes in tissue metabolites are related to perturbations of lipid metabolism, which may be helpful to further understand the AS mechanisms. This work shows that the metabolomics is a valuable tool for studying metabolic diseases.