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One new eudesmane sesquiterpene 1 and one new chromolaevane sesquiterpene 2, along with 19 known compounds, have been isolated from the invasive plant Solidago canadensis. Their structures were established by spectroscopic means, including 1D/2D-NMR and HR-ESIMS analyses. Compounds 10 and 12, in combination with fluconazole, showed significant activity in an in vitro synergistic antifungal assay against Candida albicans, with FIC values of

Simultaneously boosting the activity and selectivity of CO2 reduction catalysts remains a challenge. In this work, surface-adsorbed hydroxyl (OHad) on the SnO promoted CO2 reduction into formate th...

Hydroalkylation, the direct addition of a C(sp3)–H bond across an olefin, is a desirable strategy to produce valuable, complex structural motifs in functional materials, pharmaceuticals, and natural products. Herein, we report a reliable method for accessing α-branched amines via nickel-catalyzed hydroalkylation reactions. Specifically, by using bis(cyclooctadiene)nickel (Ni(cod)2) together with a phosphine ligand, we achieved a formal C(sp3)–H bond insertion reaction between olefins and N-sulfonyl amines without the need for an external hydride source. The amine not only provides the alkyl motif but also delivers hydride to the olefin by means of a nickel-engaged β–hydride elimination/reductive elimination process. This method provides a platform for constructing chiral α-branched amines by using a P-chiral ligand, demonstrating its potential utility in organic synthesis. Notably, a sulfonamidyl boronate complex formed in situ under basic conditions promotes ring-opening of the azanickellacycle reaction intermediate, leading to a significant improvement of the catalytic efficiency., Catalytic addition of a carbon chain and a hydrogen across a double bond has often required an added hydride source. Here the authors show a method to add alkanes with an amino functionality to olefins, wherein a nickel catalyst uses the amine itself as the hydride source, obviating an external hydride reagent.

Ti3C2Tx exhibits excellent electromagnetic (EM) shielding and electrochemical properties. However, the inherent re-stacking tendency and easy oxidation of Ti3C2Tx limit its further application. In this study, a multi-walled carbon nanotube/polyaniline composite (CNT/PANI, denoted as C–P) was introduced into Ti3C2Tx nanosheets to obtain a Ti3C2Tx–CNT/PANI composite (T@CP). Owing to the integrated effects of Ti3C2Tx and C–P, the contribution of absorption was significantly improved, which finally enhanced the EM shielding performance of T@CP. The highest total EM shielding effectiveness (SET) was close to 50 dB (49.8 dB), which was substantially higher than that of pure Ti3C2Tx (45.3 dB). Moreover, T@CP demonstrated outstanding supercapacitive performance. The specific capacitance of T@CP (2134.5 mF/cm2 at 2 mV/s) was considerably higher than that of pure Ti3C2Tx (414.3 mF/cm2 at 2 mV/s). These findings provide a new route for the development of high-efficiency Ti3C2Tx-based bifunctional EM shielding and electrochemical materials.

Elastomers with outstanding strength, toughness and healing efficiency are highly promising for many emerging fields. However, it is still a challenge to integrate all these beneficial features in one elastomer. Herein, an asymmetric alicyclic structure adjacent to aromatic disulfide was tactfully introduced into the backbone of polyurethane (PU) elastomer. Specifically, such elastomer (PU-HPS) was fabricated by polycondensing polytetramethylene ether glycol (PTMEG), isophorone diisocyanate (IPDI) and p-hydroxydiphenyl disulfide (HPS) via one-pot method. The molecular mobility and phase morphology of PU-HPS can be tuned by adjusting the HPS content. Consequently, the dynamic exchange of hydrogen and disulfide bonds in the hard segment domains can also be tailored. The optimized sample manifests outstanding tensile strength (46.4 MPa), high toughness (109.1 MJ/m3), high self-healing efficiency after fracture (90.3%), complete scratch recovery (100%) and good puncture resistance. Therefore, this work provides a facile strategy for developing robust self-healing polymers.

A novel and efficient Cu(I)-catalyzed radical heteroannulation reaction of [60]fullerene (C60) with α-bromo acetamides has been disclosed for the direct synthesis of diverse C60-fused lactams. Furthermore, the formed C60-fused lactams can be served as a versatile platform for further electrochemical functionalization to prepare 1,2-, 1,4-, 1,2,3,16-, and 1,4,9,25-adducts of C60. In addition, a representative fullerene product has been applied as an overcoating layer of the electron-transporting layer in n-type perovskite solar cell.

Solid-state polymer electrolytes are considered to be the most promising electrolytes for next-generation high-energy rechargeable lithium batteries due to the advantages of high safety, good mecha...

The adsorption characteristics and mechanisms of spirulina powder were investigated when it was used as adsorbent to recover ytterbium(III) from wastewater solution. Surface structure and element valence of the adsorbent were analyzed by SEM and XPS for the exploring of its adsorption mechanism for ytterbium(III). The adsorption characteristics of ytterbium(III) on spirulina powder was analyzed through assessing adsorption isotherm, kinetics and thermodynamic models. The adsorption isotherm data were best explained by Langmuir model, and the adsorption capacity of spirulina powder for ytterbium(III) was 72.46 mg/g when adsorption temperature was 318 K. The kinetic experiment results showed that the pseudo-second order kinetic model can better simulate the adsorption process of spirulina powder to ytterbium(III), indicating that the rate-controlling step was chemical adsorption. Spirulina can be an efficient and economical ytterbium(III) recycling material, because it showed good adsorption stability and reusability from the adsorption−desorption cycle experiment results.

Single-stranded guanine-rich RNA sequences have a propensity to fold into compact G-quadruplexes (RG4s). The conformational transitions of these molecules provide an important way to regulate their biological functions. Here, we examined the stability and conformation of an RG4-forming sequence identified near the end of human telomerase RNA. We found that a proximal single-stranded (ss) RNA significantly impairs RG4 stability at physiological K+ concentrations, resulting in a reduced RG4 rupture force of ∼ 24.4 pN and easier accessibility of the G-rich sequence. The destabilizing effect requires a minimum of six nucleotides of ssRNA and is effective at either end of RG4. Remarkably, this RG4-forming sequence, under the influence of such a proximal ssRNA, exhibits interconversions between at least three less stable RG4 conformers that might represent potential intermediates along its folding/unfolding pathway. This work provides insights into the stability and folding dynamics of RG4 that are essential for understanding its biological functions.

The digestion properties of sturgeon myofibrillar protein (MF) treated by low temperature vacuum heating (LTVH) at different processing temperatures (50, 60 and 70 °C) and times (15 and 30 min) were studied and compared with those of sturgeon MF treated by traditional cooking (TC). The results showed that as the temperature and time increased, the protein digestibility decreased, whereas the particle size and protein aggregation increased. It was observed that the band intensity of myosin heavy chain and myosin heavy chain 7 weakened; however, the band intensity of actin showed little change. MALDI-TOF-MS analysis revealed that the digested products of the samples treated by LTVH had a larger proportion of 750-1000 Da peptides than those treated by TC, which was consistent with the trend of the number of unique peptides identified in each group. Fourier transmission infrared (FT-IR) spectroscopy showed that the contents of α-helices and β-sheets exhibited negative and positive correlations with the temperature, respectively. Overall, compared to TC, LTVH can relieve the heat stress of protein conformation, reduce protein aggregation to improve the accessibility of the protein to digestive protease, and increase digestibility.

The unexpected Diels-Alder reaction of [60]fullerene (C60) with ferrocenes bearing electron-withdrawing groups as cyclopentadiene surrogates has been developed to selectively afford single isomers of [2 + 4] cycloadducts of C60. Mechanistic studies indicate that cyclopentadienes are in situ generated from electron-deficient ferrocenes in the presence of an oxidant and an acid, followed by [2 + 4] cycloadditions with dienophiles. A Michael addition reaction using a Grignard reagent has been utilized to transform the Diels-Alder adducts of C60 into more stable fullerene derivatives.

Organic polymer/inorganic particle composites with thermoelectric (TE) properties have witnessed rapid progress in recent years. Nevertheless, both development of novel polymers and optimization of compositing methods remain highly desirable. In this study, we first demonstrated a simulated in situ coagulation strategy for construction of high-performance thermoelectric materials by utilizing single-walled carbon nanotubes (SWCNTs) and a new D–A polymer TPO-TTP12 that was synthesized via incorporating dioxothiopyrone subunit into a polymeric chain. It was proven that the preparation methods have a significant influence on thermoelectric properties of the TPO-TTP12/SWCNT composites. The in situ prepared composite films tend to achieve much better thermoelectric performances than those prepared by simply mixing the corresponding polymer with SWCNTs. As a result, the in situ compositing obtains the highest Seebeck coefficient of 66.10 ± 0.05 μV K−1 at the TPO-TTP12-to-SWCNT mass ratio of 1/2, and the best electrical conductivity of up to 500.5 ± 53.3 S cm−1 at the polymer/SWCNT mass ratio of 1/20, respectively; moreover, the power factor for the in situ prepared composites reaches a maximum value of 141.94 ± 1.47 μW m−1 K−2, far higher than that of 104.68 ± 0.86 μW m−1 K−2 for the by-mixing produced composites. This indicates that the dioxothiopyrone moiety is a promising building block for constructing thermoelectric polymers, and the simulated in situ compositing strategy is a promising way to improve TE properties of composite materials.

A facile copper-promoted decarboxylative annulation of [60]fullerene (C60) with two identical α-oxocarboxylic acids via an unprecedented cascade addition pathway has been exploited to synthesize the unique epoxy-bridged C60-fused lactones for the first time. Further transformations into the rare epoxy-bridged C60-fused hemiacetals and bicyclic-fused 1,2,3,4-adducts as well as application in a perovskite solar cell device of the obtained products have also been demonstrated. The structures of the epoxy-bridged C60-fused lactones and derived reductive products have been unequivocally established by single-crystal X-ray crystallography. Plausible reaction mechanisms leading to the observed products are proposed.

An enantioselective ring-opening formal [3+2]-cycloaddition of spirovinylcyclopropyl oxindoles with enals via synergistic catalysis of palladium(0) and a chiral organocatalyst has been developed, affording spirooxindoles bearing four contiguous stereocenters in good yields with excellent enantioselectivities. The generality and utility of the protocol were also demonstrated through scale-up experiments and synthetic transformation of the resulting cycloadduct.

TiO2 is not among the traditional electromagnetic (EM) absorbing material candidates owing to its poor response in the EM wave region. Although the EM wave absorption performance can be improved by hybrid and/or hydrogenated TiO2, the difficulty and risk of the experimental process are increased. Herein, rutile TiO2 nanorod was successfully prepared by two-step method. The analysis of dielectric properties exhibits that rutile TiO2 nanorod has excellent charge storage capacity. The results of EM wave absorbing performance show that impedance matching caused by anomalous resonance leads to frequency selective absorption. Such anomalous resonance is due to the resonant polarization of ionic clusters formed by oxygen ions and titanium ions. Moreover, metastructure design shows that the EM absorption frequency and the EM wave absorption bandwidth can be tuned through the design of metamaterial. Our founding will broaden the field of vision for the design of EM wave absorbing materials in the future.

RecD family helicases play an important role in prokaryotic genome stability and serve as the structural models for studying superfamily 1B (SF1B) helicases. However, RecD-catalyzed duplex DNA unwinding behavior and the underlying mechanism are still elusive. RecD family helicases share a common proto-helicase with eukaryotic Pif1 family helicases, which are well known for their outstanding G-quadruplex (G4) unwinding ability. However, there are still controversial points as to whether and how RecD helicases unfold G4 structures. Here, single-molecule fluorescence resonance energy transfer (smFRET) and magnetic tweezers (MT) were used to study Deinococcus radiodurans RecD2 (DrRecD2)-mediated duplex DNA unwinding and resolution of G4 structures. A symmetric, repetitive unwinding phenomenon was observed on duplex DNA, revealed from the strand switch and translocation of one monomer. Furthermore, we found that DrRecD2 was able to unwind both parallel and antiparallel G4 structures without obvious topological preferences. Surprisingly, the unwinding properties of RecD on duplex and G4 DNA are different from those of Pif1. The findings provide an example, in which the patterns of two molecules derived from a common ancestor deviate during evolution, and they are of significance for understanding the unwinding mechanism and function of SF1B helicases.

A new organic–inorganic hybrid, namely [Ni2(en)4(C2H3NO2)(H2O)][Ni(en)3][Ni(en)2][P2W18O62]·6H2O (1, en = 1,2-ethylenediamine), was synthesized hydrothermally by mixing the ligands of 1,2-ethylenediamine and glycine. Notably, compound 1 exhibits the first example of coordination polymer derived from the Wells–Dawson polyoxoanions and di-nuclear nickel(II)-glycine cations. As a result, an intriguing 3D supramolecular architecture was fabricated with the [P2W18O62]6− fragments and the nickel counter-cations via hydrogen bonds. Furthermore, the compound with this unique structure exhibited outstanding electrocatalytic properties in terms of the reduction of iodate and nitrite. This work brings a new inspiration for the design and synthesis of new hybrids with functional behaviors towards various fields of catalysis.

Despite the rapid progress in peptide liquid crystals (LCs) due to their prominent properties, our investigation on flexible peptide-based LCs is incomplete, mainly resulted from their unclear formation mechanisms and unexploited applications in organic solvents. Here, we develop a lyotropic LC based on a flexible oligopeptide amphiphile, which aggregates into aligned cylinder-like nanostructures in dimethyl sulfoxide (DMSO). The formation mechanism of lyotropic LC in DMSO was probed by the experimental investigation and molecular dynamics simulation, indicating that the hydrogen bonding and hydrophobic and electrostatic interactions contribute to the formation of ordered nanostructures in the organic solvent. Arising from the orientational order and suitable fluidity, we exploit the application of lyotropic LC as an aligned medium to measure the residual dipolar couplings of bioactive molecules. This study not only offers the understanding of the mechanism to create LC systems without rigid aromatic groups but also expands the applications of ordered bottom-up nanomaterials in organic solvents.

We found that a rice NADPH oxidase gene OsRbohB contributes drought tolerance and its functions are involved in the interaction of the OsRbohB-mediated ROS production and ABA signaling. The plasma membrane NADPH oxidases, also known as respiratory burst oxidase homologs, are the key producers of ROS under both normal and stress conditions in plants. However, their functions in rice development and stress tolerance are still under investigation. Here, we found that a rice NADPH oxidase gene OsRbohB, also named OsNOX1, is expressed in all tissues examined throughout the development stages with higher transcripts in leaves. The transcriptional expression of OsRbohB is also strongly stimulated by dehydration, salt and several phytohormonal treatments. Compared with wide-type and the OsRbohB-overexpressing transgenic plants, osrbohB, a Tos17 insertion knockout mutant of OsRbohB, shows lower ROS production, abscisic acid (ABA) content and transcripts of a series of stress-related genes. The osrbohB mutant also exhibits lower seed germination rate, organ size and thousand seed weight, but higher stomatal aperture and sensitivity to drought. Moreover, a number of genes involved in plant development, stress response, transcriptional regulation, and particularly ABA signaling are differentially expressed in osrbohB plants under both normal growth and drought conditions. All these results suggest the roles of OsRbohB in drought tolerance of rice, which probably performed through the interaction of the OsRbohB-mediated ROS production and ABA signaling.

BACKGROUND Facial cosmetic procedures become popular for people with a desire to have a younger appearance, and cosmetic technology has developed rapidly over the past several decades. However, increasing complications related to cosmetic injections have been reported, and infection is one of the most serious problems and can cause anxiety and facial injury. We here report a case of Majocchi's granuloma (MG) caused by Trichophyton rubrum after facial injection of hyaluronic acid. CASE SUMMARY A 37-year-old woman presented to our hospital with a history of red papules, nodules, and abscesses on her left zygomatic arch for 2 mo. She had received a cosmetic injection of hyaluronic acid on the left side of her face prior to the appearance of the lesions. MG caused by Trichophyton rubrum after facial injection of hyaluronic acid was diagnosed based on morphology and molecular biological identification. In vitro antifungal susceptibility testing was conducted according to the Clinical and Laboratory Standards Institute M38-A2 method. Minimal inhibitory concentrations were used to evaluate the antifungal susceptibility. The antifungal agents and their minimal inhibitory concentrations for the strain were terbinafine (< 0.5 μg/mL), itraconazole (0.06 μg/mL), amphotericin B (0.25 μg/mL), fluconazole (32 μg/mL), voriconazole (0.125 μg/mL), posaconazole (0.125 μg/mL), and isavuconazole (0.06 μg/mL). We initially administered 250 mg/d oral terbinafine for 2 mo, but the patient still had painful papules, nodules and abscesses on her face. Then, we adjusted the treatment to itraconazole 400 mg/d for 8 wk based on the in vitro antifungal susceptibility testing results. The skin lesions improved significantly, and there was no recurrence during follow-up. CONCLUSION This case revealed that facial injection of hyaluronic acid may cause serious MG. Antifungal susceptibility testing should be considered in the treatment of MG caused by Trichophyton rubrum.

Grifola frondosa was cultured with Rhizoma gastrodiae alcohol extract by submerged fermentation to study the growth of mycelia and analyze the changes in the activity of extracellular enzymes related to substrate degradation. It turned out that Rhizoma gastrodiae alcohol extract at 7 g/L significantly increased the biomass of Grifola frondosa. Interestingly, levels of reducing sugars in the medium initially increased and then decreased at the last stage. Moreover, dynamic detection of mycelial biomass and extracellular enzymes involved in degradation of nutritional ingredients of the medium indicated that Rhizoma gastrodiae alcohol extract at 7 g/L stimulated the growth of mycelia and augmented the activity of extracellular enzymes to a variable extent and thus increased degradation ability of Grifola frondosa. This paper firstly revealed the mechanism for the stimulation of mycelial biomass growth in Grifola frondosa by Rhizoma gastrodiae alcohol extract in liquid culture through activity of extracellular enzymes related to the degradation of the substrates.

Glutathione S-transferases (GSTs) are multifunctional proteins that play important roles in cellular detoxification as well as in plant growth and development. Here, we cloned a new rice tau class GST gene, OsGSTU6, and evaluated its roles in regulating cadmium (Cd) stress tolerance of rice. OsGSTU6 is located both in the cytosol and nucleus of cells. The transcripts of OsGSTU6 were detected in the whole life cycle of rice with higher levels in the leaf blade and sheath at heading stage. The transcripts of OsGSTU6 were significantly stimulated by a number of environmental factors including several phytohormones, abiotic stresses, and heavy metals, suggesting its stress-responsive characteristics. Moreover, the overexpression (OE) of OsGSTU6 in rice reduced the accumulation of Cd in leaf and enhanced the tolerance of the plant to Cd stress, while knockdown (RNAi) of OsGSTU6 triggered Cd accumulation in rice leaves and decreased stress tolerance. Meanwhile, the expression levels of several candidate genes responsible for scavenging reactive oxygen species (ROS) were downregulated in OE of OsGSTU6 lines. In addition, the content of superoxide anions (O2−) and glutathione showed reduction in OE plants, but was augmented in RNAi plants under both normal growth and Cd stress, compared with wild type. Furthermore, both the yeast two-hybrid assay and firefly luciferase complementation imaging (LCI) assay demonstrated that OsGSTU6 might function with dimers in plant cells. All these results suggest that OsGSTU6 may play an important role in Cd stress tolerance of rice by involving in the intracellular ROS homeostasis.

Reactive oxygen species (ROS) homeostasis is critical for both physiological processes and stress responses of plants. NADPH oxidases (NOXs) are the key producers of ROS in plants. However, their functions in ROS homeostasis and plant growth regulation in wheat (Triticum aestivum) are little investigated. Here, we cloned and characterized a NOX isoform TaNOX7 in wheat. Overexpression of TaNOX7 in rice led to enhanced root length, ROS production, drought tolerance as well as bigger panicles and higher yield but shorter growth period duration. Further results indicate that TaCDPK13, a member of calcium-dependent protein kinases (CDPKs), can directly interact with TaNOX7 and enhance ROS production in plants. These results demonstrate that TaNOX7 plays crucial roles in wheat development, fertility, and drought tolerance via interaction with TaCDPK13, which may act as an upstream regulator of TaNOX7 to regulate ROS production in wheat.

BACKGROUND Sturgeon is popular for its nutritious value and its taste. However, sturgeon fillets are traditionally heated in 100 °C boiling water, resulting in unfavorable taste and with a negative effect on the quality. This study considered the effect of combinations of vacuum and low-temperature treatments (LTVH groups) on sturgeon fillets compared with the traditional heat treatment (TC groups). RESULTS The results show that the LTVH groups had lower cooking-loss rates. All LTVH fillets were changed to a white color, and appeared 'done', as did the TC fillets. The LTVH and TC methods gave rise to significant differences in texture: the springiness of the LTVH groups decreased with heating time, and decreased rapidly in the TC groups (P

Photothermal therapy (PTT) is a minimally invasive treatment that kills cancer cells by converting photon energy into heat. The past few decades have witnessed the booming development of photothermal materials, mainly focusing on precious metal nanomaterials and carbon nanomaterials, such as nanogold and silver and nanocarbon materials for near-infrared (NIR) light-triggered PTT. As precious metals are expensive and potentially harmful to humans, exploration and development of a new type of photothermal materials has become a research hotspot in this field. Herein, we report narrow bandgap conjugated polymer nanoparticles (PDPP NPs) based on pyrrolo[3,4-c]pyrrole-1,4-dione (DPP) with intense NIR absorption at 900 nm, as well as a photothermal energy conversion efficiency of 75%. This polymer nanoparticle is essentially non-toxic, as the cell viability of mouse remained more than 90%, even when the concentration of PDPP NPs was at 0.5 mg·mL−1.

A diastereoselectivity-controllable formal [3+2]-cycloaddition of arylvinyl oxirane 2,2-diesters with cyclic N-sulfonyl imines is developed, affording the corresponding tricyclic oxazolidine derivatives in moderate to excellent yields with excellent diastereoselectivities in the presence of palladium(0) or scandium(III) triflate. This protocol allows selective synthesis of diastereomers of tricyclic oxazolidine derivatives under switchable and mild conditions. Further transformations of the obtained products were conducted by removing ester groups and arylvinyl moieties.

The catalysis of ionic liquids (ILs) in the traditional stirred reactor suffers from insufficient mass and heat transfer, which always needs a long reaction time and results in a low reaction rate. In this work, highly efficient synthesis of 1-methoxy-2-propanol via the alcoholysis reaction of propylene oxide (PO) with methanol was proposed and achieved by the combination of micro-tubular circulating reactor with the IL [N4444][Buty] catalyst. Compared with the stirred reactor, the rate of alcoholysis reaction in a micro-tubular circulating reactor was found to be significantly improved. The reaction time was remarkably shortened to 20 min from 180 min as well as the yield of 1-methoxy-2-propanol reached 92%. Moreover, the kinetic study further demonstrated that the main reaction rate to 1-methoxy-2-propanol (K1) was about 20 times larger than the side reaction rate to byproduct 2-methoxy-1-propanol (K2) in the temperature range of 363–383 K. Such combination of micro-tubular circulating reactor with IL catalysts is believed to be a class of effective process intensification technique for highly efficient synthesis of 1-methoxy-2-propanol.

Telomeres are specific nucleoprotein structures that are located at the ends of linear eukaryotic chromosomes and play crucial roles in genomic stability. Telomere DNA consists of simple repeats of a short G-rich sequence: TTAGGG in mammals and TTTAGGG in most plants. In recent years, the mammalian telomeric G-rich repeats have been shown to form G-quadruplex (G4) structures, which are crucial for modulating telomere functions. Surprisingly, even though plant telomeres are essential for plant growth, development, and environmental adaptions, only few reports exist on plant telomeric G4 DNA (pTG4). Here, using bulk and single-molecule assays, including CD spectroscopy, and single-molecule FRET approaches, we comprehensively characterized the structure and dynamics of a typical plant telomeric sequence, d[GGG(TTTAGGG)(3)]. We found that this sequence can fold into mixed G4s in potassium, including parallel and antiparallel structures. We also directly detected intermediate dynamic transitions, including G-hairpin, parallel G-triplex, and antiparallel G-triplex structures. Moreover, we observed that pTG4 is unfolded by the AtRecQ2 helicase but not by AtRecQ3. The results of our work shed light on our understanding about the existence, topological structures, stability, intermediates, unwinding, and functions of pTG4.

An efficient and mild method has been developed for the amination of β-methoxy amides (γ-lactones) including natural products michelolide, costunolide and parthenolide derivatives by using lithium chloride in good yields. This reaction is applicable to a wide range of substrates with good functional group tolerance. Mechanism studies show that the reactions undergo a LiCl promoted MeOH elimination from the substrates to form the corresponding α,β-unsaturated intermediates followed by the Michael addition of amines.

Significant capacity degradation and a dramatic volume change call for effective strategies to address the intrinsic issues of transition metal oxide anodes of lithium-ion batteries. Rational nanostructural design has shown great promise in improving structural stability and electrochemical performance. We here report the fabrication of hollow nanoparticle-assembled hierarchical NiCo2O4 nanofibers via a facile electrospining technique and annealing process. A set of control experiments and systematic characterization demonstrate that the presence of polymers and an appropriate annealing procedure are key to form a novel nanostructured anode. The hollow nanostructure and abundant mesopores centered at about 20 nm in the nanofibers could effectively suppress severe volume variations in the lithiation/delithiation process. Furthermore, the novel nanoparticle-nanofiber hierarchical architecture could shorten the lithium diffusion length, increase the contact areas between the electrode and electrolyte, and accordingly promote fast electron/charge transfer. As expected, the optimized hierarchical NiCo2O4 nanofibers exhibit excellent performance for Li-ion batteries, delivering a capacity of 926.2 mA h g−1 at 0.1 A g−1 and 687 mA h g−1 at a high current density of 2 A g−1. This work may provide an attractive and promising strategy for advancing transition metal oxide anodes.

Developing safe, efficient and environment-friendly energy storage systems continues to inspire researchers to synthesize new electrode materials. Doping or substituting host material by some guest elements has been regarded as an effective way to improve the performance of supercapacitors. In this work, single-phase CuCo2−xNixS4 materials were synthesized by a facile two-step hydrothermal method, where Co in CuCo2S4 was substituted by Ni. Cobalt could be easily substituted with Ni in a rational range to keep its constant phase. But, a high content of Ni resulted in a multi-phase composite. Among a series of CuCo2−xNixS4 materials with different Ni/Co mole ratios, CuCo1.25Ni0.75S4 material presented a significantly high specific capacitance (647 F g−1 or 272 C g−1 at 1 A g−1) and the best cycling stability (∼98% specific capacitance retention after 10,000 charge-discharge cycles), which was mainly due to the modified composition, specific single phase, higher electroconductivity, more electroactive sites and the synergistic effect between Ni and Co. Moreover, the assembled asymmetric capacitor using CuCo1.25Ni0.75S4 as a positive electrode and activated carbon as a negative electrode delivered a high energy density of 31.8 Wh kg−1 at the power density of 412.5 W kg−1. These results demonstrated that ternary metal sulfides of CuCo2−xNixS4 are promising electrode materials for high-performance supercapacitors.

BackgroundHazy weather significantly increase air pollution and affect light intensity which may also affect medicinal plants growth.Syringa oblataLindl. (S. oblata), an effective anti-biofilm medicinal plants, is also vulnerable to changes in plant photoperiods and other abiotic stress responses. Rutin, one of the flavonoids, is the main bioactive ingredient inS. oblatathat inhibitsStreptococcus suisbiofilm formation. Thus, the present study aims to explore the biosynthesis and molecular basis of flavonoids inS. oblatain response to different light intensity.ResultsIn this study, it was shown that compared with natural (Z0) and 25% ~ 35% (Z2) light intensities, the rutin content ofS. oblataunder 50% ~ 60% (Z1) light intensity increased significantly. In addition, an integrated analysis of metabolome and transcriptome was performed using light intensity stress conditions from two kinds of light intensities whichS. oblatawas subjected to: Z0and Z1. The results revealed that differential metabolites and genes were mainly related to the flavonoid biosynthetic pathway. We found out that 13 putative structural genes and a transcription factorbHLHwere significantly up-regulated in Z1. Among them, integration analysis showed that 3 putative structural genes including4CL1,CYP73AandCYP75B1significantly up-regulated the rutin biosynthesis,suggesting that these putative genes may be involved in regulating the flavonoid biosynthetic pathway, thereby making them key target genes in the whole metabolic process.ConclusionsThe present study provided helpful information to search for the novel putative genes that are potential targets forS. oblatain response to light intensity.

The development of chiral architectures for chiral ligand and catalyst discovery is essential for asymmetric catalysis. Herein, we report the concise synthesis of a Si-centered spirocyclic skeleton, spirobiphenoxasilin-diol (SPOSiOL), and its derived chiral ligands. Using the chemical resolution method, the optical SPOSiOL could be obtained in high yield on a gram scale. Preliminary studies indicated that this ligand scaffold has great potential in transition metal-catalyzed asymmetric reactions. This finding further highlights that the Si-centered spirocyclic scaffolds are of great value in asymmetric catalysis.

Licorice (Glycyrrhiza glabra) is extensively used owing to the superior pharmacological effects. However, its maximum application potential has not been fully exploited due to the limitation of currently available extraction solvent and methods. In this study, an eco-friendly deep eutectic solvent (NADESs) based ultrasound-assisted extraction (DES-UAE) method was applied to prepare licorice extracts. The DES-UAE using choline chloride and lactic acid as solvent was optimized and modeled by using response surface methodology to maximize the extraction yields of glabridin (GLA) and isoliquiritigenin (ISL). The optimized extracts possessed higher contents of GLA and ISL than available extraction methods, and the enriched products showed superior pharmacological activities in vitro. Furthermore, scanning electron microscopy (SEM) and molecular dynamic simulation analyses were performed to deeply investigate the interaction between solvent and targeted compounds. This study not only provides an eco-friendly method for high-efficient extraction of GLA and ISL from licorice but also illustrates the mechanism of the increased extraction efficacy, which may contribute to the application of licorice and deep insight into extraction mechanism using DES.

The nucleic acid-based technique has been widely utilized in many fields including for on-site detection. However, traditional molecular detection techniques encounter limitations like relying on instruments, time consuming or complex operation, and cannot meet the demands of on-site testing. In this study, a rapid DNA extraction method (RDEM), recombinase aided amplification (RAA), and chemical heating packet (CHP) are integrated and termed as RRC platform for on-site detection of nucleic acid. For demonstration purposes, SHZD32-1 (a new transgenic soybean line from China) was detected using the novel platform to demonstrate its feasibility and capability for on-site detection. Using the RDEM, high-quality DNA appropriate for molecular detection was quickly extracted in 3–5 min. The heat energy generated by CHP was met the temperature requirements of RAA. Using the RRC platform, the whole detection process can be accomplished within only 30 min, and the results can be visually detected with glasses under blue light. No special or expensive instrument was needed for the detection process. This study provides a novel approach for on-site detection of nucleic acids besides providing valuable insight on related future research.

Bridged lactones frequently appear as structural fragments in natural products. To elucidate their stereochemistry using electronic circular dichroism (ECD) spectra, Beecham correlated the sign of the Cotton effect (CE) from the n → π* transition of lactones at approximately 220 nm with the skeleton of bridged lactones. By combining experimental and theoretical ECD analyses of various bridged lactones using time-dependent density functional theory calculations and a methodology for extracting core structures, Beecham's rule was revisited and revised to define the scope of application. Both the position of the β-C atom in the larger lactone system and the additive contribution of groups at β-C exerted effects on the sign of the CE. The revised rule provides an alternative way to interpret experimental ECD data in addition to quantum-chemical calculation for various bridged lactones.

Pesticide adjuvants (PAs) are important components of pesticide. Nonetheless, limited information is available regarding their toxic effects on biota in terrestrial ecosystem. In the present study, the mortality, growth inhibition ratio, and avoidance behavior of Eisenia fetida were examined to investigate the ecotoxicological effects of toluene, xylene, and trichloroethylene and further their mixture. The 24 h median lethal concentration (24 h-LC50) of the three PAs were 300.23, 1190.45, and 5332.36 mg/kg, and the 48 h-LC50 values were 221.62, 962.89, and 4522.41 mg/kg, respectively. The mixture exhibited significant synergistic effect on the E. fetida. There was significant growth inhibition on E. fetida by the tested PAs. The avoidance threshold values of E. fetida for the tested PAs were 1100 mg/kg, 250 mg/kg, 5000 mg/kg, and 25% of the mixture, respectively. The results evaluated the toxic effects of the three PAs and their mixture on E. fetida, provided a basis for ecotoxicological risk assessment of PAs in the soil ecosystem.

PurposeDipeptidylpeptidase-4 (DPP-4) inhibitors, including linagliptin, alogliptin, saxagliptin, sitagliptin, and vildagliptin, are used for the treatment of type 2 diabetes mellitus (T2DM) patients in China. This study assessed the economic outcomes of different DPP-4 inhibitors in patients with T2DM inadequately controlled with metformin in the Chinese context.Materials and MethodsIn this study, the validated Chinese Outcomes Model for T2DM (COMT) was conducted to project economic outcomes from the perspective of Chinese healthcare service providers. Efficacy and safety, medical expenditure, and utility data were derived from the literature, which were assigned to model variables. The primary outputs of the model included the lifetime costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER). One-way and probability sensitivity analysis was conducted to assess the potential uncertainties of parameters.ResultsOf the five competing strategies, alogliptin 25 mg strategy yielded the most significant health outcome, which associated with improvements in discounted QALY of 0.007, 0.014, 0.011, and 0.022 versus linagliptin 5 mg, saxagliptin 5 mg, sitagliptin 100 mg and vildagliptin50 mg, respectively. The sitagliptin 100 mg strategy was the cheapest option. The ICER of alogliptin 25 mg against sitagliptin 100 mg strategy was $6,952 per additional QALY gained, and the rest of the strategies were dominated or extended dominated. The most influential parameters were the cost of DPP-4 inhibitors and their treatment efficacy.ConclusionsThese results suggested that alogliptin was a preferred treatment option compared with other DPP-4 inhibitors for Chinese patients whose T2DM are inadequately controlled on metformin monotherapy.

Pesticide adjuvants (PAs) denote the general term for auxiliaries in pesticide preparations except for the active components. Toluene, chloroform, and trichloroethylene are the three most commonly used PAs as organic solvents. The residues of the three chemicals in the process of production and application of pesticides may endanger the ecosystem. In the present study, the mutagenicity of toluene, chloroform, and trichloroethylene as well the mixture of the three chemicals was tested by the Salmonella typhimurium reverse mutation test (Ames test) with TA97, TA98, TA100, and TA102 strains in the system with and without rat liver microsomal preparations (S9). The four tester strains have been used for more than 40 years to detect mutagenic compounds in chemicals, cosmetics, and environmental samples. The mutagenicity was detected on tester strains in the separated experiment from the three chemicals. The addition of S9 decreased the mutation ratios of toluene to four strains, except for the TA100 strain, but increased the mutation ratios of chloroform to four strains except for the TA98 strain. Trichloroethylene caused positive mutagenicity to become negative on the TA102 strain. In the mixed experiment, positive effects were detected only on the TA102 strain in the absence of S9. The addition of S9 increased the mutagenicity except for the TA102 strain. The mixture of toluene, chloroform, and trichloroethylene showed antagonism in mutagenicity to tester strains, except for the TA102 strain without S9. However, the mixture showed a synergistic effect to tester strains after adding S9 except for the TA98 strain.

Recently, smart nanomaterials from peptide self-assembly have received extensive attention in the field of biological and medical applications. Through rationally designing the molecular structure, we constructed a borono-peptide that self-assembled into well-defined nanofibers. Relying on the specific recognition between the vicinal diol compound and boronic acid, a novel alizarin red S (ARS)-borono-peptide (BP) spherical nanoindicator was fabricated, accompanying with the emission of strong fluorescent signal. The fluorescent nanoindicator displayed an intense response to copper(II) ions and underwent the fluorescent "turn-off" due to the strong binding-induced displacement. Originating from the high selectivity toward copper(II) ions, good biocompatibility and cancer cell targeting, the nanoindicator offered the opportunity to image copper(II) ions in cancer cells via fluorescent change.

Single-stranded DNA (ssDNA) covered with the heterotrimeric Replication Protein A (RPA) complex is a central intermediate of DNA replication and repair. How RPA is regulated to ensure the fidelity of DNA replication and repair remains poorly understood. Yeast Rtt105 is an RPA-interacting protein required for RPA nuclear import and efficient ssDNA binding. Here, we describe an important role of Rtt105 in high-fidelity DNA replication and recombination and demonstrate that these functions of Rtt105 primarily depend on its regulation of RPA. The deletion of RTT105 causes elevated spontaneous DNA mutations with large duplications or deletions mediated by microhomologies. Rtt105 is recruited to DNA double-stranded break (DSB) ends where it promotes RPA assembly and homologous recombination repair by gene conversion or break-induced replication. In contrast, Rtt105 attenuates DSB repair by the mutagenic single-strand annealing or alternative end joining pathway. Thus, Rtt105-mediated regulation of RPA promotes high-fidelity replication and recombination while suppressing repair by deleterious pathways. Finally, we show that the human RPA-interacting protein hRIP-α, a putative functional homolog of Rtt105, also stimulates RPA assembly on ssDNA, suggesting the conservation of an Rtt105-mediated mechanism.

Single-molecule imaging is emerging as a revolutionary approach to studying fundamental questions in plants. However, compared with its use in animals, the application of single-molecule imaging in plants is still underexplored. Here, we review the applications, advantages, and challenges of single-molecule fluorescence imaging in plant systems from the perspective of methodology. Firstly, we provide a general overview of single-molecule imaging methods and their principles. Next, we summarize the unprecedented quantitative details that can be obtained using single-molecule techniques compared to bulk assays. Finally, we discuss the main problems encountered at this stage and provide possible solutions.