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Hierarchical and periodic nanostructures of dielectrics or metals are highly demanded for wide applications in optical, electrical, biological, and quantum devices. In this work, programmable plasmonic–photonic hierarchical nanostructures are fabricated using a facile and effective method with high controllability and stable reproducibility. The fabrication involves colloidal self-assembly, metal film deposition, and pulsed laser-induced dewetting in sequence for controllably pairing metal nanostructures on dielectric nanospheres in either large area or a local precision. Au nanostructures including Au nanocrown (AuNC), large Au nanosphere (AuNS), and multiple small Au nanoparticles (AuNPs) have been paired one-on-one on assembled SiO2 nanosphere (SiO2NS) arrays, with size and shape controlled by correlating the laser fluence and irradiation time, and the Au film thickness. The fabricated hierarchical nanostructures demonstrate synergistic effect of the photonic effects from the monolayer SiO2NS arrays and the surface plasma resonance effect from the Au nanostructures. The dewetting induced metal film reshaping has been modeled theoretically corresponding to observed experimental results. We can directly “write” the plasmonic Au nanostructures on the photonic crystal array using a focused laser beam to form encode patterns, showing angle-dependent structural colors for anti-counterfeiting information storage and display in rigid/flexible and opaque/transparent devices. It provides a promising path to actively construct on-demand pixelated plasmonic–photonic arrays for optical multiplexing technology in sensing, information encryption, and display.

Aptamers have been widely used in the detection, diagnosis, and treatment of cancer. Owing to their special binding affinity toward cancer-related biomarkers, aptamers can be used for targeted drug delivery or bio-sensing/bio-imaging in various scenarios. The interfacial properties of aptamers play important roles in controlling the surface charge, recognition efficiency, and binding affinity of drug-delivering lipid-based carriers. In this research, the interfacial behaviors, such as surface orientation, molecular conformation, and adsorption kinetics of conjugated AS1411 molecules at different cationic lipid bilayer interfaces were investigated by sum frequency generation vibrational spectroscopy (SFG-VS)

BackgroundFor cavity-nesting birds, the nest entrance plays an important role in preventing predators from accessing nests. Several species of nuthatches use mud to narrow the entrance of cavities. In theory, the smaller the entrance hole size, the more effective it is against predators; however, few studies have tested whether narrowing the entrance hole size can affect the estimation of threat levels from nest predators in cavity-nesting birds.MethodsUsing dummy experiments, we tested whether Eurasian Nuthatches (Sitta europaea, narrow the entrance hole of cavities) and Cinereous Tits (Parus cinereus, do not narrow the entrance hole, as a control) perform different nest defence behaviours against Common Chipmunks (Tamias sibiricus, small nest predator) and Red Squirrels (Sciurus vulgaris, larger nest predator).ResultsBoth nuthatches and tits exhibited stronger response behaviours (high dummy response scores) against chipmunks than against squirrels. Compared with tits, nuthatches exhibited more aggressive behaviours to chipmunks, but their responses to squirrels were similar.ConclusionsNest defence behaviours of nuthatches to chipmunks differed from tits, and the results suggested that nuthatches might estimate threat levels of nest predators according to their narrowed entrance-hole size.

During liver regeneration after partial hepatectomy, the function and metabolic pathways governing transient lipid droplet accumulation in hepatocytes remain obscure. Mammalian target of rapamycin 2 (mTORC2) facilitates de novo synthesis of hepatic lipids. Under normal conditions and in tumorigenesis, decreased levels of triglyceride (TG) and fatty acids (FAs) are observed in the mTORC2-deficient liver. However, during liver regeneration, their levels increase in the absence of mTORC2.Rictor liver-specific knockout and control mice underwent partial hepatectomy, followed by measurement of TG and FA contents during liver regeneration. FA metabolism was evaluated by analyzing the expression of FA metabolism-related genes and proteins. Intraperitoneal injection of the peroxisome proliferator-activated receptor α (PPAR-α) agonist, p53 inhibitor, and protein kinase B (AKT) activator was performed to verify the regulatory pathways involved. Lipid mass spectrometry was performed to identify the potential PPAR-α activators.The expression of FA metabolism-related genes and proteins suggested that FAs are mainly transported into hepatocytes during liver regeneration. The PPAR-α pathway is down-regulated significantly in the mTORC2-deficient liver, resulting in the accumulation of TGs. The PPAR-α agonist WY-14643 rescued deficient liver regeneration and survival in mTORC2-deficient mice. Furthermore, lipidomic analysis suggested that mTORC2 deficiency substantially reduced glucosylceramide (GluCer) content. GluCer activated PPAR-α. GluCer treatment in vivo restored the regenerative ability and survival rates in the mTORC2-deficient group.Our data suggest that FAs are mainly transported into hepatocytes during liver regeneration, and their metabolism is facilitated by mTORC2 through the GluCer-PPAR-α pathway, thereby establishing a novel role for mTORC2 in lipid metabolism.

In this work, a 3D-framework of functionalized multi-walled carbon nanotubes (fMWCNTs) decorated with molecularly imprinted polymer (MIP), has been fabricated to achieve fast and ultrasensitive electrochemical molecular sensing. The cavity networks of MIP layer from Norfloxacin (NFX) molecules offers simultaneous identification and quantification of NFX; and thus, ensures its high selectivity. The porous structure of fMWCNT 3D-framwork effectively increases the specific surface area, and the copolymer of fMWCNTs and MIP shows synergistic effect for electrocatalytic reaction of NFX at the modified sensor. Under optimized conditions, the fabricated sensors show wide linear detection ranges of 0.003-0.391 μM and 0.391–3.125 μM, low limit of determination (LOD) of 1.58 nM, and excellent selectivity in discriminating NFX according to its structural analogues and possible interferences. Precise and fast quantification of NFX in pharmaceutical formulations (Yunnan Baiyao and Ouyi Pharmaceutical) and rat plasma samples (N = 4) suggests its simplicity and reliability. The recoveries from pharmaceutical formulations ranged from 97.36 to 109.58% with the precisions (relative standard deviations, RSD, n = 3) of 1.74–3.41%; and the recoveries from rat plasma samples ranged from 83.00 to 115.67% with RSDs (n = 3) of 0.45–10.30%. Considering the advantages of easy fabrication, and selective and sensitive detection, such sensors with different types of MIPs would be widely applied in the fields of pharmaceutical analysis, and environmental and clinical therapeutic drug monitoring.

Water-in-water (w/w) emulsions are particularly advantageous for biomedical-related applications, such as cell encapsulation, bioreactors, biocompatible storage, and processing of biomacromolecules. However, due to ultralow interfacial tension, generation and stabilization of uniform w/w droplets are challenging. In this work, we report a strategy of creating stable and size-controllable w/w droplets that can quickly form polyelectrolyte microcapsules (PEMCs) in a microfluidic device. A three-phase (inner, middle, outer) aqueous system was applied to create a stream of inner phase, which could be broken into droplets via a mechanical perturbation frequency, with size determined by the stream diameter and vibration frequency. The interfacial complexation is formed via electrostatic interaction of polycations of poly(diallyldimethylammoniumchloride) with polyanions of polystyrene sodium sulfate in the inner and outer phases. With addition of negatively charged silica nanoparticles, the stability, permeability, and mechanical strength of the PEMC shell could be well manipulated. Prepared PEMCs were verified by encapsulating fluorescein isothiocyanate-labeled dextran molecules and stimuli-triggered release by varying the pH value or osmotic pressure. A model enzyme, trypsin, was successfully encapsulated into PEMCs and released without impairing their catalytic activity. These results highlight its potential applications for efficient encapsulation, storage, delivery, and release of chemical, biological, pharmaceutical, and therapeutic agents.

The complete mitochondrial DNA genome of the Salangid icefish (Neosalanx taihuensis) was sequenced by the primer walking sequence method. The entire mitochondrial genome of this species is 17,035 bp in length, making it the longest among the reported mitochondrial genomes of Osmeriformes. It contains 13 protein-coding genes, 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and one control region (CR). The gene arrangement, nucleotide composition, and codon usage pattern of the mitochondrial genome are similar to those of other teleosts except for two long tandem repeats in the CR. A 486 bp tandem repeat fragment was identified that comprises 2 copies of 243 bp motif and accounts approximately 35.5% of the CR. The 243 bp tandem repeat motif can be folded into a stem-loop secondary structure. Phylogenetic analysis based on 12 concatenated protein-coding genes of the heavy strand shows the genus Neosalanx diverged most recently and clustered with Protosalanx hyalocranius as a clade.

Human insulin-like growth factor-I (IGF-I) is a pleiotropic polypeptide hormone, which has been widely utilized for the diagnosis and management of growth hormone (GH) related disorders and diseases. In this work, we verify a label-free optical biosensor based on nematic liquid crystals (LCs) of 4-cyano-4-pentylbiphenyl (5CB) for ultrasensitive sensing of trace IGF-I in human serum samples. 5CB shows unique birefringence driven by the reorientation of the self-assembled N, N-dimethyl-N-(3-(trimethoxysilyl)propyl)−1-octadecanaminiuchloride (DMOAP) on glass. IGF-I antibody (AbIGF-I), as a specific recognition element, can be immobilized onto modified glass surface through a cross-linker of glutaradehyde (GA) and (3-aminopropyl) trimethoxysilane (APTES). Based on the number of specific recognition and binding between antibody (AbIGF-1) and antigen (AgIGF-1), the LC film exhibits gradual change from dark to bright under crossed polarizer. Under optimized conditions, the constructed LC-based biosensor demonstrates high sensitivity to IGF-I with a detection limit (LOD) of 1.0 ng/mL and a linear range of 10.0–2000.0 ng/mL (R2 = 0.989). This detection method possesses the advantages of easy construction, rapid sensing, good stability and repeatability, and high specificity for distinguishing IGF-I from other interfering proteins. Meanwhile, the format of biosensor could quickly detect IGF-I within a physiological range, providing profound information for prevention and treatment of GH-IGF-I axis related diseases in clinical diagnosis.

To achieve an ultrasensitive biosensor, the modified nanomaterials with high specific surface area, proper chemical and electrical/optical properties are highly required. In the present work, we designed a rapid and ultrasensitive label-free electrochemical immunosensor for interleukin-6 (IL-6) detection based on nanoporous mesoporous-carbon (NMC) composite decorated with gold nanoparticles (NMC@AuNPs). The NMC served as the transducer matrix, which is modified on the surface of glassy carbon electrode (GCE), to deposit the gold nanoparticles (AuNPs). NMC is synthesized via a wrinkled SiO2-nanoparticle (wSiO2NP) assisted sacrificing strategy, which displays an interconnected 3D structure to achieve high specific surface area and abundant porous for rapid sample enrichment; meanwhile, the composited hierarchical porous structure promotes the deposition and entanglement of AuNPs to form stable NMC@AuNPs and achieve enhanced electrical conductivity. Specific antibody against IL-6 protein is immobilized onto the surface of AuNPs, based on the antibody-antigen recognition strategy, the constructed immunosensors demonstrate high sensitivity and selectivity for assay of IL-6 with a linear dynamic range of 0.5–1200 pg mL−1 and the ultralow limit of detection (LOD) of 0.14 pg mL−1. Toward the detection of IL-6 in human serum samples, this label-free biosensor with a short detection period (within 60 min, including sample processing and electrochemical measurement). Moreover, the label-free biosensor exhibited an excellent sensitivity and specificity, suggesting it possesses the potential for other biomarkers in point-of-care biosensing application.

Porous carbon-based nanomaterials have attracted much attention because of their specific structure and multifunctionality. We report on a strategy for constructing porous microparticles consisting of carbon nanotubes (CNTs) connected with honeycomb nanopores and their application for electrochemical sensors. The microdroplets containing silica nanoparticles (SiO2NPs) and CNTs are created using a microfluidic device, with droplet size and composition being tunable via the fluidic phases. Solid microparticles consisting of close-packed SiO2NPs and CNTs (SiO2NP-CNT-μPs) are obtained after water evaporation and calcination. Target honeycomb CNT-microparticles (h-CNT-μPs) are achieved after removing SiO2NPs from the SiO2NP-CNT-μPs. The glassy carbon electrodes (GCEs) modified with h-CNT-μPs and Nafion (h-CNT-μPs/Nafion/GCEs) show highly enhanced specific surface area and electrocatalytic activity. Under optimized conditions, h-CNT-μPs/Nafion/GCEs exhibit linear response to methyl parathion (MP) in the concentration ranges of 0.3–20.0 μM and 20.0–150.0 μM with the limit of detection of 0.092 μM (S/N = 3), showing good sensitivity, selectivity, reproducibility and anti-interference. Prepared electrochemical sensors have also been applied for determination of MP in practical samples of tomato and cabbage, showing comparable results to those measured using a high-performance liquid chromatography (HPLC). This proposed strategy is highly efficient for constructing microscale sensor units considering their size, uniformity and compositions, providing a reliable way for monitoring pesticide and other active components in fruits, vegetables and other scenarios of agricultural and industrial production.

The complete mitochondrial DNA genome of the Salangid icefish (Neosalanx taihuensis) was sequenced by the primer walking sequence method. The entire mitochondrial genome of this species is 17,035 b...

Self-biting is a chronic disease, which cause wound to take effect on mink growth and pelt quality. In this study, we firstly adopted RAPD (random amplification polymorphism DNA) technique based on the reproducible 26 polymorphism primers screened from 100 random primers to analyze hereditary constitution of the samples from healthy minks and self-biting minks, respectively, at molecular level to aim to discuss the causes of self-biting. The results showed that 29 straps showed polymorphism among amplified 105 straps, of which the polymorphism rate is 27.62%. Between healthy and sick mink groups, the amplified DNA fragment through different primers indicated different distribution frequency. The similarity coefficient of mink groups is 0.8471 and genetic distance (variation) index is 0.1529. Through primer S356 (whose sequence is CTGCTTAGGG), we amplified different straps between healthy and sick mink. The amplified 1000 bp DNA fragment in the sick mink groups can preliminarily serve as molecular genetic label to distinguish from healthy and sick mink groups to gradually remove the mink individual of self-biting, achieve to purify mink groups and reduce economy loss of mink breeding industry. This work provide theoretical basis for further study on molecular breeding and disease prevention of mink.