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Sturgeons display a slow growth rate and delayed initial sexual maturity, which extends the captive breeding and conservation processes. To date, few studies have revealed the molecular mechanism underlying the growth difference of sturgeons. In the present study, juvenile Yangtze sturgeons (Acipenser dabryanus) with different growth rates were selected from the same cultured pool for muscle structure, enzyme activity and comparative transcriptome analysis. Histological assays showed that the fiber diameter of the fast-growing group was significantly larger than that of the slow-growing group. The activities of four glycometabolism related enzymes, including two key rate-limiting enzymes hexokinase and pyruvate kinase, were significantly higher in fast-growing group. RNA-Seq of muscle tissues identified 7408 differentially expressed genes (DEGs), which consisted of 3637 upregulated genes and 3771 downregulated genes, in the fast-growing group vs. the slow-growing group. In the brain, a total of 12,213 unigenes were differentially expressed (6050 upregulated unigenes and 6163 downregulated unigenes) between the two groups. The expression levels of IGF1 and IGF1-binding proteins (IGFBPs) in muscle were significantly higher in the fast-growing group and might be promising candidate biomarkers for measuring growth performance in Yangtze sturgeon. Two myogenic regulatory factors (myog and myf6) were significantly upregulated, which indicated that the growth variation in juvenile Yangtze sturgeon might be partly due to the difference in the differentiation of muscle cells. In addition, pathway enrichment analysis revealed that the glycolysis and cell cycle pathways were significantly enhanced in the fast-growing groups, suggesting that they might also play important roles in the improved growth performance of A. dabryanus. Furthermore, the WGCNA as well as hub gene network analyses supported that cell cycle and gluconeogenesis might be involved in the differential growth performance of A. dabryanus. The results of this study may contribute to our understanding of the underlying molecular mechanism of growth variation in fish. • Muscle histological analysis revealed faster speed of muscle hypertrophy in the fast growth group. • RNA-Seq results indicated growth variation was due to differentiation difference of muscle cells. • GH/IGF regulatory system was upregulated in the fast-growing group of sturgeons. • Glycolysis and cell cycle pathways were also the endogenous factors that contribute to better growth performance. • WGCNA analysis revealed that cyclin and GAPDH were among the top key hub genes. [ABSTRACT FROM AUTHOR]

AbstractSpectroscopy has become prominent in medical surveillance due to its low cost, speed, and nondestructive testing. However, the issue of class unbalance in medical data causes existing algorithms to favor the majority classes, leading to their malfunction. This study attempts to propose a parallel type method based on two modified feature selection methods to achieve visible spectral discrimination of unbalanced urine specific gravity (USG) data. Firstly, the root mean square error (RMSE) of successive projections algorithm (SPA) and competitive adaptive reweighted sampling (CARS) were modified by increasing weight coefficients. Then, SPA, CARS, modified SPA (mSPA), modified CARS (mCARS), tandem connection of SPA and CARS (CARS-SPA), tandem connection of mSPA and CARS (mCARS mSPA), parallel connection of SPA and CARS (CARS + SPA), and parallel connection of mSPA and CARS (mCARS + mSPA) were used to select characteristic wavelengths from the full spectrq. Finally, based on the variable subsets extracted by each method, the random forest (RF) models were established to verify the performance of the parallel strategy and modification method. The results showed that the RF model of mCARS + mSPA achieved effective discrimination of USG with high accuracy (92.81%), high sensitivity (0.9270), and high resolution (0.9280). It means that a parallel hybrid based on two modified feature selection methods can effectively select feature wavelengths beneficial for minority class recognition, achieving the mining of spectral features of unbalanced data. At the same time, this study also provides a novel example of the strategy of parallel feature selection methods. [ABSTRACT FROM AUTHOR]

Type I acyl-CoA: diacylglycerol acyltransferase (DGAT1) is a rate-limiting enzyme that catalyses the final step of the Kennedy pathway in triacylglycerol biosynthesis. In this study, two genes encoding type I diacylglycerol acyltransferase, ZmDGAT1a and ZmDGAT1b, were cloned from a high-oil maize inbred line and confirmed by Southern blotting. The complete coding sequences were obtained. Comparison between genomic DNA and coding sequences revealed that both ZmDGAT1a and ZmDGAT1b comprised 16 exons and 15 introns with a coding region of 1485 and 1488 bp, respectively. ZmDGAT1a and ZmDGAT1b shared similar molecular mass, isoelectric point, and transmembrane domains. ZmDGAT1b was expressed in all sampled tissues that were examined by using reverse transcription-polymerase chain reaction (RT-PCR). In contrast, ZmDGAT1a expression was limited to the silks, tassels, and seeds of different ages. This suggests that the two genes do not have a complementary relationship. The ZmDGAT1a and ZmDGAT1b proteins were subsequently found to be localized in the endoplasmic reticulum (ER). The data provides an important basis for further studies of the functions of DGAT1 genes and for genetic modification of the oil content and composition of corn seeds. [ABSTRACT FROM AUTHOR]

A new method that combines scanning ion beam etching (IBE) and dynamic chemical etching (DCE) is proposed to tracelessly remove the subsurface damage (SSD) layer of fused silica optics to improve their laser-induced damage resistant performance. Several characterization techniques are employed to investigate the influence of the etching depth of each individual step on the optical properties of the treated sample surfaces, which helps to provide a guide for its implementation in practice as well as improve our understanding on the mechanism of the proposed combined method. The results indicate that traceless removing of SSD layer is accomplished with a shallow 0.3 μm-IBE treatment. Nevertheless, secondary defects such as metal contaminations are introduced at the same time, which induces optical absorption even higher than that of the conventionally polished sample. These secondary defects can be effectively removed with a 3 μm-DCE treatment, achieving high-quality surface with laser-induced damage threshold much higher than that of the 10 μm-DCE etched sample and surface roughness as low as that of the virgin sample. The combined treatment of scanning IBE and DCE shows an excellent performance in improving the damage resistance of fused silica optics without deteriorating their surface quality. • Proposed the combination of scanning IBE and DCE in improving LIDT of fused silica. • Revealed the role of each step (i.e., IBE and DCE) in improving LIDT. • Revealed that there was an optimal matching of IBE and DCE depths. • Demonstrated the excellent performance of this method in improving LIDT. • Paved a new way in treating large-aperture fused silica optics with combined method. [ABSTRACT FROM AUTHOR]

Rapid and sensitive determination of pesticide residues in fruits and vegetables is critical for human health and ecosystems. This paper used an Ag-modified CuO sphere-cavity array (CuO@Ag) electrode as a thiram SERS/electrochemical dual readout detection platform. Numerous Raman "hotspots" generated by uniformly distributed silver nanoparticles, charge transfer at the CuO@Ag interface, and the formation of Ag-thiram complexes contribute to the significant enhancement of this SERS substrate, which results in excellent SERS performance with an enhancement factor up to 1.42 × 106. When using SERS as the readout technique, the linear range of the substrate for thiram detection was 0.05–20 nM with a detection limit (LOD) of up to 0.0067 nM. Meanwhile, a correlation between the value of change in current density and thiram concentration was established due to the formation of stable complexes of thiram with Cu2+ generated at specific potentials. The linear range of electrochemical detection was 0.05–20.0 μM, and the detection limit was 0.0167 μM. The newly devised dual-readout sensor offers notable sensitivity and stability. The two signal readout methods complement each other in terms of linear range and detection limit, making it a convenient tool for assessing thiram residue levels in agro-food. At the same time, the combination of commercially available portable equipment makes on-site monitoring possible. Ag-modified CuO cavity arrays have been established as SERS-electrochemical dual-signal platforms for thiram detection. [Display omitted] • CuO@Ag cavity arrays were used as SERS/electrochemical dual-signal sensors. • The EM and CT synergistic effect endow CuO@Ag with excellent SERS performance. • The highly ordered array structure ensures excellent SERS signal reproducibility. • The complex between the electrode and thiram enhances the electrochemical response. • The sensor demonstrated the feasibility of detecting thiram in real samples. [ABSTRACT FROM AUTHOR]

• An activatable raspberry-like biomimetic nanoplatform was designed. • Site-specific delivery of CuS NPs and CpG to cancer cells and TAMs was achieved. • Immunogenicity and suppression were regulated by deep PTT and TAMs re-education. • Spatiotemporal and robust photoimmunotherapy inhibited tumor growth and metastasis. Smart nanomedicine capable of stimulating the immunity cycle and synchronously modulating the tumor immunosuppressive microenvironment is highly desirable for treatment of malignant solid tumor. Herein, an activable biomimetic raspberry like nanoplatform (abbreviated as RCuS@tMCP) was created for photothermal cascade immunotherapy by the spatiotemporal control of immunogenic tumor cell death (ICD) and tumor associated macrophages (TAMs) reprogramming. RCuS@tMCP was developed by conjugating the second near-infrared (NIR-II) photothermal agent copper sulfide nanoparticles (CuS NPs) as the "raspberry seeds" on the surface of biomimic CpG/protamine immunocore (denoted as tMCP) through matrix metalloproteinase-2 cleavable peptide. In the tumor microenvironment, RCuS@tMCP enzymatically unlocked the small sized RGDK peptide modified CuS NPs (ca.12 nm), which penetrated deeply and specifically to α v β 3 overexpressed tumor cells and elicited in situ ICD under NIR-II laser irradiation, thus triggering an effective antitumor immune response. Meanwhile, the remaining tMCP precisely recognized TAMs under the guidance of M2 peptide and reeducated them to tumoricidal ones, thereby boosted the power of cytotoxic T lymphocytes. By the spatiotemporal cooperation, RCuS@tMCP significantly inhibited the tumor growth of both primary and distant 4T1 tumors and prevented malignant metastasis as demonstrated both in vitro and in vivo data. This study provides an appealing and intelligent therapeutic toolbox for efficient immunological cascade therapy. [ABSTRACT FROM AUTHOR]

Metasurfaces, being composed of subwavelength nanostructures, can achieve peculiar optical manipulations of phase, amplitude, etc. A large field of view (FOV) is always one of the most desirable characteristics of optical systems. In this study, metasurface-based quadratic reflectors (i.e., meta-reflectors) made of HfO2 nanopillars are investigated to realize a large FOV at infrared wavelengths. First, the geometrical dependence of HfO2 nanopillars' phase difference is analyzed to show the general principles of designing infrared HfO2 metasurfaces. Then, two meta-reflectors with a quadratic phase profile are investigated to show their large FOV, subwavelength resolution, and long focal depth. Furthermore, the two quadratic reflectors also show a large FOV when deflecting a laser beam with a deflecting-angle range of approximately ±80°. This study presents a flat optical metamaterial with a large FOV for imaging and deflecting, which can greatly simplify the optical–mechanical complexity of infrared systems, particularly with potential applications in high-power optical systems. [ABSTRACT FROM AUTHOR]

A highly ordered CuO@Ag SPE with excellent peroxidase properties has been established for on-site SERS detection of leuco crystal violet in aquatic products. [Display omitted] • CuO@AgNPs nanozyme screen-printed electrodes have been developed for catalysis and SERS detection. • Various preparation methods facilitate the laboratory and industrial manufacture of the CuO@Ag SPE. • The EM and CT synergistic effect endows CuO@Ag SPE with excellent SERS performance. • The highly ordered cavity array structure ensures excellent SERS signal reproducibility. • The sensor demonstrates the feasibility of on-site detection of leuco crystal violet in aquatic products. The research on the use of metal–semiconductor hybrid systems for constructing chemical and biological sensors has received increasing attention. In this work, a screen-printed electrode (SPE) with peroxidase activity was developed using AgNPs decorated CuO cavity array (CuO@Ag SPE) for on-site SERS detection of Leuco crystal violet (LCV) in aquatic products. The low Michaelis-Menten constant (K m = 42.8 μM) and the high maximum reaction velocity (V m = 5.1 × 10−8 mol·L−1s−1) indicate that the CuO@Ag SPE has a strong affinity and excellent catalytic efficiency. Moreover, this substrate has a considerable SERS enhancement with EF of 6.1 × 106, resulting from the synergetic effect of the electromagnetic enhancement (EM) and chemical enhancement (CM) after modifying noble metal onto semiconductor materials. The CuO@Ag SPE can efficiently catalyze the oxidation of the Raman-inactive reporter (LCV) and simultaneously act as SERS-active substrates for detecting the generated Raman-active crystal violet (CV), providing a relatively wide linear range (2.0 nM-2.0 μM) and a lower detection limit (0.3 nM). The recoveries obtained from the proposed SPE range from 100.1 to 109.2% and RSD from 4.9 to 10.4%, demonstrating that the SPE has high accuracy and reliability in real sample detection. [ABSTRACT FROM AUTHOR]

In this study, the high-efficiency phase control Si metasurfaces are investigated based on aperiodic nanoarrays unlike widely-used period structures, the aperiodicity of which providing additional freedom to improve metasurfaces' performance. Firstly, the phase control mechanism of Huygens nanoblocks is demonstrated, particularly the internal electromagnetic resonances and the manipulation of effective electrical/magnetic polarizabilities. Then, a group of high-transmission Si nanoblocks with 2π phase control is sought by sweeping the geometrical parameters. Finally, several metasurfaces, such as grating and parabolic lens, are numerically realized by the nanostructures with high efficiency. The conversion efficiency of the grating reaches 80%, and the focusing conversion efficiency of the metalens is 99.3%. The results show that the high-efficiency phase control metasurfaces can be realized based on aperiodic nanoarrays, i.e., additional design freedom. [ABSTRACT FROM AUTHOR]