Kjeldsenmayer0822

For battery-like processes, a high C' is only observed at the voltage at which the material stores charge, while outside that voltage, C' is negligible. The three-dimensional (3D) Bode analysis allows charge-storage dynamics to be mapped out in great detail with more delineation between mechanisms compared to the more frequently deployed kinetic analyses derived from cyclic voltammetry.Extraction of chemicals from biota leads to co-extraction of lipids. When dosing such extracts into in vitro bioassays, co-dosed lipids act as an additional phase that can reduce the bioavailability of the chemicals and the apparent sensitivity of the assay. Equilibrium partitioning between medium, cells, and co-dosed lipids was described with an existing equilibrium partitioning model for cell-based bioassays extended by an additional lipid phase. We experimentally investigated the influence of co-dosed lipids on the effects elicited by four test chemicals of different hydrophobicity in two bioassays, indicative of the aryl hydrocarbon receptor and oxidative stress response (AREc32). The partitioning model explained the effect of the test chemicals in the presence of spiked triolein within a factor of 0.33-5.83 between the measured and predicted effect concentration (EC). We applied the model to marine mammal blubber extracted with silicone. Extracts dosed in the AREc32 bioassay showed a linear increase of apparent EC with increasing lipid fraction. The partitioning model was used to interpret the role of the co-extracted lipid. A quantitative lipid correction of bioassay results in the presence of co-dosed lipids was possible for known compounds and defined mixtures, while we could only estimate a range for mixtures of unknown chemicals.The study of controlling the molecular self-assembly of aqueous soft matter is a fundamental scheme across multiple disciplines such as physics, chemistry, biology, and materials science. In this work, we use liquid-crystal polymer networks (LCNs) to control the superstructures of one aqueous soft material called lyotropic chromonic liquid crystals (LCLCs), which shows spontaneous orientational order by stacking the plank-like molecules into elongated aggregates. We synthesize a layer of patterned LCN films by a nematic liquid-crystal host in which the spatially varying molecular orientations are predesigned by plasmonic photopatterning. We demonstrate that the LCLC aggregates are oriented parallel to the polymer filaments of the LCN film. This patterned aqueous soft material shows immediate application for controlling the dynamics of swimming bacteria. The demonstrated control of the supramolecular assembly of aqueous soft matter by using a stimuli-responsive LCN film will find applications in designing dynamic advanced materials for bioengineering applications.In deep burn injuries, the dermis of the skin is often severely damaged, and hair follicles are also lost and lose the potential for regeneration. Therefore, the development of wound dressings that promote hair follicle regeneration has important clinical significance. In this study, inspired by an ancient Chinese medicine prescription, a novel fibrous membrane (P/Qu/Cup; P, PCL; Qu, quercetin; Cup, cuprorivaite, CaCuSi4O10) containing quercetin-copper (Qu-Cu) chelates was fabricated by using quercetin and a highly bioactive bioceramic (CaCuSi4O10) incorporated in PCL/gelatin electrospun fibers. The fibrous membrane can effectively release Qu and Cu ions to induce proliferation, migration, and differentiation of skin and hair follicle related cells, and the Qu, Cu ions, and Si ions released from the composite membrane revealed synergistic activity to stimulate hair follicle regeneration and wound healing. Our study demonstrated that the analysis of the common components in ancient Chinese prescription is an effective approach to design novel bioactive materials for regenerative medicine.Totopotensamide A (TPM A, 1) is a polyketide-peptide glycoside featuring a nonproteinogenic amino acid 4-chloro-6-methyl-5,7-dihydroxyphenylglycine (ClMeDPG). The biosynthetic gene cluster (BGC) of totopotensamides (tot) was previously activated by manipulating transcription regulators in marine-derived Streptomyces pactum SCSIO 02999. Herein, we report the heterologous expression of the tot BGC in Streptomyces lividans TK64, and the production improvement of TPM A via in-frame deletion of two negative regulators totR5 and totR3. The formation of ClMeDPG was proposed to require six enzymes, including four enzymes TotC1C2C3C4 for 3,5-dihydroxyphenylglycine (DPG) biosynthesis and two modifying enzymes TotH (halogenase) and TotM (methyltransferase). Heterologous expression of the four-gene cassette totC1C2C3C4 led to production of 3,5-dihydroxyphenylglyoxylate (DPGX). The aminotransferase TotC4 was biochemically characterized to convert DPGX to S-DPG. Inactivation of totH led to a mutant accumulated a deschloro derivative TPM H1, and the ΔtotHi/ΔtotMi double mutant afforded two deschloro-desmethyl products TPMs HM1 and HM2. A hydrolysis experiment demonstrated that the DPG moiety in TPM HM2 was S-DPG, consistent with that of the TotC4 enzymatic product. These results confirmed that TotH and TotM were responsible for ClMeDPG biosynthesis. Bioinformatics analysis indicated that both TotH and TotM might act on thiolation domain-tethered substrates. This study provided evidence for deciphering enzymes leading to ClMeDPG in TPM A, and unambiguously determined its absolute configuration as S.Actin cytoskeleton disruption is a promising and intriguing anticancer strategy, but their efficiency is frequently compromised by severe side effects of the actin cytoskeleton-disrupting agents. In this study, we constructed the biocompatible actin cytoskeleton-targeting multivalent supramolecular assemblies that specifically target and disrupt the tumor actin cytoskeleton for cancer therapy. The assemblies were composed of β-cyclodextrin-grafted hyaluronic acid (HACD) and iron oxide magnetic nanoparticles (MNPs) grafted by an actin-binding peptide (ABP) and adamantane (Ada)-modified polylysine. Owing to the multivalent binding between cyclodextrin and Ada, HACD, and peptide-grafted MNPs (MNP-ABP-Ada) could self-assemble to form MNP-ABP-Ada⊂HACD nanofibers in a geomagnetism-dependent manner. Furthermore, the presence of ABP rendered the assemblies to efficiently target the actin cytoskeleton. Interestingly, with the acid of a low-frequency alternating magnetic field (200 Hz), the actin cytoskeleton-targeting nanofibers could induce severe actin disruption, leading to a remarkable cell cycle arrest and drastic cell death of tumor cells both in vitro and in vivo, but showed no obvious toxicity to normal cells. The actin cytoskeleton-targeting/disrupting supramolecular assembly implies an excellent strategy for realizing efficient cancer therapy.Designing solid-state perovskite oxide solar cells with large short circuit current (JSC) and open circuit voltage (VOC) has been a challenging problem. Epitaxial BiFeO3 (BFO) films are known to exhibit large VOC (>50 V). However, they exhibit low JSC (≪μA/cm2) under 1 Sun illumination. In this work, taking polycrystalline BiFeO3 thin films, we demonstrate that oxygen vacancies (VO) present within the lattice and at grain boundary (GB) can explicitly be controlled to achieve high JSC and VOC simultaneously. While aliovalent substitution (Ca2+ at Bi3+ site) is used to control the lattice VO, Ca and Ti cosubstitution is used to bring out only GB-VO. Fluorine-doped tin oxide (FTO)/Bi1-xCaxFe1-yTiyO3-δ/Au devices are tested for photovoltaic characteristics. Introducing VO increases the photocurrent by four orders (JSC ∼ 3 mA/cm2). On the contrary, VOC is found to be less then 0.5 V, as against 0.5-3 V observed for the pristine BiFeO3. Ca and Ti cosubstitution facilitate the formation of smaller crystallites, which in turn increase the GB area and thereby the GB-VO. This creates defect bands occupying the bulk band gap, as inferred from the diffused reflection spectra and band structure calculations, leading to a three-order increase in JSC. The cosubstitution, following a charge compensation mechanism, decreases the lattice VO concentration significantly to retain the ferroelectric nature with enhanced polarization. It helps to achieve VOC (3-8 V) much larger than that of BiFeO3 (0.5-3 V). It is noteworthy that as Ca substitution maintains moderate crystallite size, the lattice VO concentration dominates GB-VO concentration. click here Notwithstanding, both lattice and GB-VO contribute to the increase in JSC; the former weakens ferroelectricity, and as a consequence, undesirably, VOC is lowered well below 0.5 V. Using optimum JSC and VOC, we demonstrate that the efficiency ∼0.22% can be achieved in solid-state BFO solar cells under AM 1.5 one Sun illumination.Pesticides, extensively used in agriculture production, have received enormous attention because of their potential threats to the environment and human health. Hence, in this study, a kind of highly sensitive and stable hybrid surface-enhanced Raman scattering (SERS)-active substrates constructed with flower-like two-dimensional molybdenum sulfide and Ag (MoS2@Ag) has been developed, and then the above substrate was sequentially utilized in the recyclable detection of pesticide residues on several kinds of fruits and vegetables. In the first place, the excellent photocatalytic performance of the MoS2@Ag hybrid substrate was demonstrated, which was attributed to the inhibition of electron-hole combination after the formation of Schottky barrier between the Ag NPs and MoS2 matrix. Thereafter, two calibration curves with ultra-low limits of detection (LOD) as 6.4 × 10-7 and 9.8 × 10-7 mg/mL were established for the standard solutions of thiram (tetramethylthiuram disulfide, TMTD) and methyl parathion (MP), and then the recyclable assay of their single and mixed residues on eggplant, Chinese cabbage, grape, and strawberry was successfully realized. It is interesting to note that the detection recoveries from 95.5 to 63.1% for TMTD and 92.3 to 62.6% for MP are greatly dependent on the size and surface roughness of these foods. In a word, the MoS2@Ag composite matrix shows attractive SERS and photocatalysis performance, and it is expected to have the potential application on food safety monitoring.Thermochromic films with intriguing functionalities have great potential in soft actuators, heat storage devices, and interactive interface sensors. Inspired by the unique features of bird feathers (such as Nicobar pigeon, Anna hummingbird, mandarin duck, etc.), a superhydrophobic thermochromic film (STF) with robust healability is proposed for the first time through sandwiching an electric heater between a top thermochromic layer and a bottom poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) substrate. The STF exhibits fast and reversible color conversions of blue-pink-yellow under a low input power and has a superhydrophobic property with a contact angle of 155°. Furthermore, owing to the strong dynamic dipole-dipole interactions between the polar CF3 groups of flexible PVDF-HFP chains, the STF possesses a robust healing capability of structure and conductivity. By means of the temperature difference generated by the objects contacting (finger, iron, and water) as a stimulus, the STFs achieve tactile imaging and writing record with advantages of transient display, automatic erasure, and excellent reusability.