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In ocean remote sensing missions, recognizing an underwater acoustic target is a crucial technology for conducting marine biological surveys, ocean explorations, and other scientific activities that take place in water. The complex acoustic propagation characteristics present significant challenges for the recognition of underwater acoustic targets (UATR). Methods such as extracting the DEMON spectrum of a signal and inputting it into an artificial neural network for recognition, and fusing the multidimensional features of a signal for recognition, have been proposed. However, there is still room for improvement in terms of noise immunity, improved computational performance, and reduced reliance on specialized knowledge. In this article, we propose the Residual Attentional Convolutional Neural Network (RACNN), a convolutional neural network that quickly and accurately recognize the type of ship-radiated noise. This network is capable of extracting internal features of Mel Frequency Cepstral Coefficients (MFCC) of the underwater ship-radiated noise. Experimental results demonstrate that the proposed model achieves an overall accuracy of 99.34% on the ShipsEar dataset, surpassing conventional recognition methods and other deep learning models.

The current research proposes a novel method for printing continuous carbon fiber composite parts. At first, continuous carbon fiber prepreg filament for Fused Deposition Modeling 3D printing was manufactured, followed by modification of extruder head of 3D printers to print the filament. Thereafter, three-point flexural test and Response Surface Methodology were adopted to study the mechanical properties of the composite parts printed with the filament. After testing, a mathematical model was developed to describe and analyze the relationship between the printing parameters (printing temperature, printing speed, and layer thickness) and the flexural strength of printed composite parts. We discovered that the flexural strength and flexural modulus of printed composites significantly improved with the proposed method with specified printing parameters, and while of all the parameters, the layer thickness had the greatest contribution towards the final flexural strength. The results indicate that the discussed method could be a promising approach to print CCF composites.

Phytoremediation is a promising means of ameliorating heavy metal pollution through the use of transgenic plants as artificial hyperaccumulators. A novel Streptococcus thermophilus γ-glutamylcysteine synthetase-glutathione synthetase (StGCS-GS) that synthesizes glutathione (GSH) with limited feedback inhibition was overexpressed in sugar beet (Beta vulgaris L.), yielding three transgenic lines (s2, s4 and s5) with enhanced tolerance to different concentrations of cadmium, zinc and copper, as indicated by their increased biomass, root length and relative growth compared with wild-type plants. Transgenic sugar beets accumulated more Cd, Zn and Cu ions in shoots than wild-type, as well as higher GSH and phytochelatin (PC) levels under different heavy metal stresses. This enhanced heavy metal tolerance and increased accumulation were likely due to the increased expression of StGCS-GS and consequent overproduction of both GSH and PC. Furthermore, when multiple heavy metal ions were present at the same time, transgenic sugar beets overexpressing StGCS-GS resisted two or three of the metal combinations (50 μM Cd-Zn, Cd-Cu, Zn-Cu and Cd-Zn-Cu), with greater absorption in shoots. Additionally, there was no obvious competition between metals. Overall, the results demonstrate the explicit role of StGCS-GS in enhancing Cd, Zn and Cu tolerance and accumulation in transgenic sugar beet, which may represent a highly promising new tool for phytoremediation.

Three-dimensional (3D) porous ZnO–CuO hierarchical nanocomposites (HNCs) nonenzymatic glucose electrodes with different thicknesses were fabricated by coelectrospinning and compared with 3D mixed ZnO/CuO nanowires (NWs) and pure CuO NWs electrodes. The structural characterization revealed that the ZnO–CuO HNCs were composed of the ZnO and CuO mixed NWs trunk (~200 nm), whose outer surface was attached with small CuO nanoparticles (NPs). Moreover, a good synergetic effect between CuO and ZnO was confirmed. The nonenzymatic biosensing properties of as prepared 3D porous electrodes based on fluorine doped tin oxide (FTO) were studied and the results indicated that the sensing properties of 3D porous ZnO–CuO HNCs electrodes were significantly improved and depended strongly on the thickness of the HNCs. At an applied potential of + 0.7 V, the optimum ZnO–CuO HNCs electrode presented a high sensitivity of 3066.4 μAmM −1 cm −2 , the linear range up to 1.6 mM and low practical detection limit of 0.21 μM. It also showed outstanding long term stability, good reproducibility, excellent selectivity and accurate measurement in real serum sample. The formation of special hierarchical heterojunction and the well-constructed 3D structure were the main reasons for the enhanced nonenzymatic biosensing behavior.

A series of In 2 O 3 /Au nanorods (NRs) were fabricated and characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X–ray diffractometer (XRD) and X–ray photoelectron spectroscopy (XPS). The length to diameter ratios of In 2 O 3 /Au NRs was periodically modulated in the range of 2.9–4.5 through controlling the initial content of indium salt and reaction time. Their gas sensing properties to volatile organic compounds (VOCs) were carefully studied and then applied in exhaled breath detection. The results demonstrate that In 2 O 3 /Au NRs gas sensor can effectively detect acetone at 250 °C and ethanol at 400 °C. The corresponding actual detection limit is as low as 0.1 ppm to acetone and 0.05 ppm to ethanol, respectively. Moreover, by using humidity compensation method, In 2 O 3 /Au NRs gas sensor can clearly distinguish the acetone and ethanol biomarkers in human breath. The main reason of the enhanced gas sensing properties was attributed to the “spillover effects” between Au and In 2 O 3 NRs. The excellent sensing performance indicates that In 2 O 3 /Au NRs is a promising functional material to actual application in monitoring and detecting diabetes and safe driving area in a noninvasive and more accurate way.

Background Sugar beet ( Beta vulgari s L.) is a globally important sucrose-producing crop. As a “nitrogen (N)-responsive species”, it specifically relies on precise N management to maximize agroeconomic potential. However, excessive N application reduces sucrose accumulation efficiency and elevates non-sucrose constituents despite increasing root biomass. Clarifying the molecular regulatory mechanisms underlying low nitrogen (LN) response is therefore essential for improving nitrogen use efficiency (NUE) of sugar beet. Results Comparative transcriptomics of sugar beet germplasm ‘780016B/12 Superior’ under normal (CV, 5 mmol/L N) and low nitrogen (LN, 0.5 mmol/L N) conditions after 12 h of treatment identified 120 and 254 differentially expressed long non-coding RNAs (DELs) in foliage and roots, respectively. Functional annotation of 1,454 long noncoding RNA-message RNA (lncRNA-mRNA) pairs (trans/cis = 3.47:1) revealed the coordinated regulation of DEL-target genes in nitrogen metabolism, transmembrane transport, and plant hormone signal transduction. Within these LN responsive networks, lncRNAs of XR_791134.2 and LNC_011801 functioned as key components, which correlated with glutamine synthetase ( GS2 )-mediated ammonium assimilation and auxin transporter-like protein (AUX2/3/4) suppression redirecting nitrogen resources, respectively. Additionally, competing endogenous RNA (ceRNA) networks further integrated hormonal signaling with nitrogen sensing. Specifically, lncRNA LNC_016830 is situated at a critical junction point, that interacted with miR396a/b-5p to regulate auxin-sensitive transcription factors GRF7/9 and coordinated ABA signaling through CRWN3 -mediated ABI5 degradation. Crucially, most of ceRNA-associated mRNAs were targets of growth-suppressing hormones, including the brassinosteroid receptor SR160, a dual regulator that links lncRNA networks to steroid-mediated stress responses. Conclusions This study reveals lncRNAs as key correlates balancing nitrogen assimilation and developmental plasticity in sugar beet, and provides molecular targets for breeding high NUE cultivars.

Nitrogen (N) is an essential macronutrient for plants, acting as a common limiting factor for crop yield. The application of nitrogen fertilizer is related to the sustainable development of both crops and the environment. To further explore the molecular response of sugar beet under low nitrogen (LN) supply, transcriptome analysis was performed on the LN-tolerant germplasm ‘780016B/12 superior’. In total, 580 differentially expressed genes (DEGs) were identified in leaves, and 1,075 DEGs were identified in roots (log 2 |FC| ≥ 1; q value < 0.05). Gene Ontology (GO), protein−protein interaction (PPI), and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses clarified the role and relationship of DEGs under LN stress. Most of the downregulated DEGs were closely related to “photosynthesis” and the metabolism of “photosynthesis-antenna proteins”, “carbon”, “nitrogen”, and “glutathione”, while the upregulated DEGs were involved in flavonoid and phenylalanine biosynthesis. For example, GLUDB (glutamate dehydrogenase B) was identified as a key downregulated gene, linking carbon, nitrogen, and glutamate metabolism. Thus, low nitrogen-tolerant sugar beet reduced energy expenditure mainly by reducing the synthesis of energy-consuming amino acids, which in turn improved tolerance to low nitrogen stress. The glutathione metabolism biosynthesis pathway was promoted to quench reactive oxygen species (ROS) and protect cells from oxidative damage. The expression levels of nitrogen assimilation and amino acid transport genes, such as NRT2.5 (high-affinity nitrate transporter), NR (nitrate reductase [NADH]), NIR (ferredoxin-nitrite reductase), GS (glutamine synthetase leaf isozyme), GLUDB, GST (glutathione transferase) and GGT3 (glutathione hydrolase 3) at low nitrogen levels play a decisive role in nitrogen utilization and may affect the conversion of the carbon skeleton. DFRA (dihydroflavonol 4-reductase) in roots was negatively correlated with NIR in leaves (coefficient = −0.98, p < 0.05), suggesting that there may be corresponding remote regulation between “flavonoid biosynthesis” and “nitrogen metabolism” in roots and leaves. FBP (fructose 1,6-bisphosphatase) and PGK (phosphoglycerate kinase) were significantly positively correlated (p < 0.001) with Ci (intercellular CO 2 concentration). The reliability and reproducibility of the RNA-seq data were further confirmed by real-time fluorescence quantitative PCR (qRT−PCR) validation of 22 genes (R 2 = 0.98). This study reveals possible pivotal genes and metabolic pathways for sugar beet adaptation to nitrogen-deficient environments.

Background Sugar beet ( Beta vulgaris L.) is an economically essential sugar crop worldwide. Its agronomic traits are highly diverse and phenotypically plastic, influencing taproot yield and quality. The National Beet Medium-term Gene Bank in China maintains more than 1700 beet germplasms with diverse countries of origin. However, it lacks detailed genetic background associated with morphological variability and diversity. Results Here, a comprehensive genome-wide association study (GWAS) of 13 agronomic traits was conducted in a panel of 977 sugar beet accessions. Almost all phenotypic traits exhibited wide genetic diversity and high coefficient of variation (CV). A total of 170,750 high-quality single-nucleotide polymorphisms (SNPs) were obtained using the genotyping-by-sequencing (GBS). Neighbour-joining phylogenetic analysis, principal component analysis, population structure and kinship showed no obvious relationships among these genotypes based on subgroups or regional sources. GWAS was carried out using a mixed linear model, and 159 significant associations were detected for these traits. Within the 25 kb linkage disequilibrium decay of the associated markers, NRT1/PTR FAMILY 6.3 ( BVRB_5g097760 ); nudix hydrolase 15 ( BVRB_8g182070 ) and TRANSPORT INHIBITOR RESPONSE 1 ( BVRB_8g181550 ); transcription factor MYB77 ( BVRB_2g023500 ); and ethylene-responsive transcription factor ERF014 ( BVRB_1g000090 ) were predicted to be strongly associated with the taproot traits of root groove depth (RGD); root shape (RS); crown size (CS); and flesh colour (FC), respectively. For the aboveground traits, UDP-glycosyltransferase 79B6 ( BVRB_9g223780 ) and NAC domain-containing protein 7 ( BVRB_5g097990 ); F-box protein At1g10780 ( BVRB_6g140760 ); phosphate transporter PHO1 ( BVRB_3g048660 ); F-box protein CPR1 ( BVRB_8g181140 ); and transcription factor MYB77 ( BVRB_2g023500 ) and alcohol acyltransferase 9 ( BVRB_2g023460 ) might be associated with the hypocotyl colour (HC); plant type (PT); petiole length (PL); cotyledon size (C); and fascicled leaf type (FLT) of sugar beet, respectively. AP-2 complex subunit mu ( BVRB_5g106130 ), trihelix transcription factor ASIL2 ( BVRB_2g041790 ) and late embryogenesis abundant protein 18 ( BVRB_5g106150 ) might be involved in pollen quantity (PQ) variation. The candidate genes extensively participated in hormone response, nitrogen and phosphorus transportation, secondary metabolism, fertilization and embryo maturation. Conclusions The genetic basis of agronomical traits is complicated in heterozygous diploid sugar beet. The putative valuable genes found in this study will help further elucidate the molecular mechanism of each phenotypic trait for beet breeding.

In order to determine the different roles of rice (Oryza sativa L.) cytosolic ascorbate peroxidases (OsAPXa and OsAPXb, GenBank accession nos. D45423 and AB053297, respectively) under salt stress, transgenic Arabidopsis plants over-expressing OsAPXa or OsAPXb were generated, and they all exhibited increased tolerance to salt stress compared to wild-type plants. Moreover, transgenic lines over-expressing OsAPXb showed higher salt tolerance than OsAPXa transgenic lines as indicated by root length and total chlorophyll content. In addition to ascorbate peroxidase (APX) activity, antioxidant enzyme activities of catalase (CAT), superoxide dismutase (SOD) and glutathione reductase (GR), which are also involved in the salt tolerance process, and the content of H₂O₂ were also assayed in both transgenic and wild-type plants. The results showed that the overproduction of OsAPXb enhanced and maintained APX activity to a much higher degree than OsAPXa in transgenic Arabidopsis during treatment with different concentrations of NaCl, enhanced the active oxygen scavenging system, and protected plants from salt stress by equilibrating H₂O₂ metabolism. Our findings suggest that the rice cytosolic OsAPXb gene has a more functional role than OsAPXa in the improvement of salt tolerance in transgenic plants.

Photovoltaic devices employing lead halide perovskites as the photoactive layer have attracted enormous attention due to their commercialization potential. Yet, there exists challenges on the way to the practical use of perovskite solar cells (PSCs), such as light stability and current–voltage (J–V ) hysteresis. Inorganic perovskite nanocrystals (IPNCs) are promising candidates for high‐performance photovoltaic devices due to their simple synthesis methods, tunable bandgap, and efficient photon downshifting effect for ultraviolet (UV) light blocking and conversion. In this work, CsPbBr3 IPNCs modification could give rise to the vapor phase and solution‐processed PSCs with a power conversion efficiency (PCE) of 16.4% and 20.8%, respectively, increased by 11.6% and 5.6% compared to the control devices for more efficient UV utilization and carrier recombination suppression. As far as is known, 11.6% is the most effective enhanced factor for PSCs based on photon downshifting effect inside of devices. The CsPbBr3 layer could also significantly retard light‐induced degradation, leading to the lifetime over 100 h under UV illumination for PSCs. Additionally, the modified PSCs exhibit weak hysteresis and multiple colors of fluorescence. These results shed light on the future design of combining a photon downshifting layer and carrier interfacial modification layer in the applications of perovskite optoelectronic devices. Inorganic perovskite quantum dots can be used as efficient luminescent down converting layers for ultraviolet blocking and conversion in traditional perovskite solar cells. In this work, a new cell configuration by integrating CsPbBr3 inside of device structure is demonstrated. The modified devices could exhibit weak hysteresis, improved photoelectric performance, and multiple colors of fluorescence.