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Variegation and complexity of polarization relaxation loss in many heterostructured materials provide available mechanisms to seek a strong electromagnetic wave (EMW) absorption performance. Here we construct a unique heterostructured compound that bonds α-Fe2O3 nanosheets of the (110) plane on carbon microtubes (CMTs). Through effective alignment between the Fermi energy level of CMTs and the conduction band position of α-Fe2O3 nanosheets at the interface, we attain substantial polarization relaxation loss via novel atomic valence reversal between Fe(III) â Fe(III-) induced with periodic electron injection from conductive CMTs under EMW irradiation to give α-Fe2O3 nanosheets. Such heterostructured materials possess currently reported minimum reflection loss of -84.01 dB centered at 10.99 GHz at a thickness of 3.19 mm and an effective absorption bandwidth (reflection loss ≤ -10 dB) of 7.17 GHz (10.83-18 GHz) at 2.65 mm. This work provides an effective strategy for designing strong EMW absorbers by combining highly efficient electron injection and atomic valence reversal.
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Tin (Sn)-based materials are expected to realize efficient CO2 electroreduction into formate. Herein, we constructed a heterojunction by depositing Cu on Cu-doped SnS2 nanosheets. During the electrochemical reaction, this heterojunction evolves to a highly active phase of Cu2O@Cu6Sn5 while maintaining its two-dimensional morphology. Specifically, a partial current density of 35 mA cm-2 with an impressive faradaic efficiency of 93% for formate production was achieved over the evolved heterojunction. In situ and ex situ experiments elucidated the formation mechanism of the Cu2O@Cu6Sn5 heterojunction. Cu6Sn5 nanosheets were formed via a stepwise desulfurization process, while Cu2O was generated through its reaction with hydroxyl radicals. This evolved heterojunction with a high electrochemically active surface area synergistically stabilized the *OCHO intermediate, thereby significantly enhancing the selectivity and activity. Our findings provide insight into the structural evolution process and guide the development of selective electrocatalysts for CO2 reduction.
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BACKGROUND: Lima bean protein isolate (LPI) is an underutilized plant protein. Similar to other plant proteins, it may display poor emulsification properties. In order to improve its emulsifying properties, one effective approach is using protein and polysaccharide mixtures. This work investigated the structural and emulsifying properties of LPI as well as the development of an LPI/xanthan gum (XG)-stabilized oil-in-water emulsion. RESULTS: The highest protein solubility (84.14%) of LPI was observed and the molecular weights (Mw ) of most LPI subunits were less than 35 kDa. The enhanced emulsifying activity index (15.97 m2 g-1 ) of LPI might be associated with its relatively high protein solubility and more low-Mw subunits (Mw < 35 kDa). The effects of oil volume fraction (Ï) on droplet size, microstructure, rheological behavior and stability of emulsions were investigated. As Ï increased from 0.2 to 0.8, the emulsion was arranged from spherical and dispersed oil droplets to polyhedral packing of oil droplets adjacent to each other, while the LPI/XG mixtures changed from particles (in the uncrowded interfacial layer) to lamellae (in the crowded interfacial layer). When Ï was 0.6, the emulsion was in a transitional state with the coexistence of particles and lamellar structures on the oil droplet surface. The LPI/XG-stabilized emulsions with Ï values of 0.6-0.8 showed the highest stability during a 14-day storage period. CONCLUSION: This study developed a promising plant-based protein resource, LPI, and demonstrates potential application of LPI/XG as an emulsifying stabilizer in foods. © 2023 Society of Chemical Industry.
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Phaseolus , Proteínas de Plantas , Emulsões/química , Proteínas de Plantas/química , Polissacarídeos Bacterianos/química , Água/químicaRESUMO
BACKGROUND: The genetic locus responsible for duck body size has been fully explained before, but the growth trait-related genetic basis is still waiting to be explored. For example, the genetic site related to growth rate, an important economic trait affecting marketing weight and feeding cost, is still unclear. Here, we performed genome wide association study (GWAS) to identify growth rate-associated genes and mutations. RESULT: In the current study, the body weight data of 358 ducks were recorded every 10 days from hatching to 120 days of age. According to the growth curve, we evaluated the relative and absolute growth rates (RGR and AGR) of 5 stages during the early rapid growth period. GWAS results for RGRs identified 31 significant SNPs on autosomes, and these SNPs were annotated by 24 protein-coding genes. Fourteen autosomal SNPs were significantly associated with AGRs. In addition, 4 shared significant SNPs were identified as having an association with both AGR and RGR, which were Chr2: 11483045 C>T, Chr2: 13750217 G>A, Chr2: 42508231 G>A and Chr2: 43644612 C>T. Among them, Chr2: 11483045 C>T, Chr2: 42508231 G>A, and Chr2: 43644612 C>T were annotated by ASAP1, LYN and CABYR, respectively. ASAP1 and LYN have already been proven to play roles in the growth and development of other species. In addition, we genotyped every duck using the most significant SNP (Chr2: 42508231 G>A) and compared the growth rate difference among each genotype population. The results showed that the growth rates of individuals carrying the Chr2: 42508231 A allele were significantly lower than those without this allele. Moreover, the results of the Mendelian randomization (MR) analysis supported the idea that the growth rate and birth weight had a causal effect on the adult body weight, with the growth rate having a greater effect size. CONCLUSION: In this study, 41 SNPs significantly related to growth rate were identified. In addition, we considered that the ASAP1 and LYN genes are essential candidate genes affecting the duck growth rate. The growth rate also showed the potential to be used as a reliable predictor of adult weight, providing a theoretical reference for preselection.
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Patos , Estudo de Associação Genômica Ampla , Humanos , Adulto , Animais , Patos/genética , Locos de Características Quantitativas , Genótipo , Peso Corporal/genética , Polimorfismo de Nucleotídeo ÚnicoRESUMO
N-Glycosylation is often essential for the structure and function of proteins. However, N-glycosylated proteins from natural sources exhibit considerable heterogeneity in the appended oligosaccharides, bringing daunting challenges to corresponding basic research and therapeutic applications. To address this issue, various synthetic, enzymatic, and chemoenzymatic approaches have been elegantly designed. Utilizing the endoglycosidase-catalyzed transglycosylation method, a single N-acetylglucosamine (N-GlcNAc, analogous to a tree stump) on proteins can be converted to various homogeneous N-glycosylated forms, thereby becoming the focus of research efforts. In this concept article, we briefly introduce the methods that allow the generation of N-GlcNAc and its close analogues on proteins and peptides and highlight the current challenges and opportunities the scientific community is facing.
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Glicoproteínas , Polissacarídeos , Glicoproteínas/metabolismo , Glicosilação , Polissacarídeos/química , Oligossacarídeos/metabolismo , Glicosídeo Hidrolases/metabolismoRESUMO
Reversible regulation of ferroelectric polarization possesses great potentials recently in bionic neural networks. Photoinduced cis-trans isomers have changeable dipole moments, but they cannot be directed to some specific orientation. Here, we construct a host-guest composite structure which consists of a porous ferroelectric metal (Ni)-organic framework [Ni(DPA)2] as host and photoisomer, azobenzene (AZB), as guest molecules. When AZB molecules are embedded in the nanopores of Ni(DPA)2 in the form of a single molecule, polarization strength tunable regulation is realized after ultraviolet irradiation of 365 and 405 nm via cis-trans isomerism transformation of AZB. An intrinsic built-in field originating from the distorted {NiN2O4} octahedra in Ni(DPA)2 directs the dipole moments of AZB to the applied electric field. As a result, the overlapped ferroelectric polarization strength changes with content of cis-AZB after ultraviolet and visible irradiation. Such a connection of ferroelectric Ni(DPA)2 structure with cis-trans isomers provides an important strategy for regulating the ferroelectric polarization strength.
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Estruturas Metalorgânicas , Isomerismo , Luz , Raios UltravioletaRESUMO
Post-translational modifications (PTMs) occurring on lysine residues, especially diverse forms of acylations, have seen rapid growth over the past two decades. Among them, lactylation and ß-hydroxybutyrylation of lysine side-chains are newly identified histone marks and their implications in physiology and diseases have aroused broad research interest. Meanwhile, lysine lipoylation is highly conserved in diverse organisms and well known for its pivotal role in central metabolic pathways. Recent findings in the proteomic profiling of protein lipoylation have nonetheless suggested a pressing need for an extensive investigation. For both basic and applied research, it is necessary to prepare PTM-bearing proteins particularly in a site-specific manner. Herein, we use genetic code expansion to site-specifically generate these lysine PTMs, including lactylation, ß-hydroxybutyrylation and lipoylation in proteins in E.â coli and mammalian cells. Notably, using strategies including activity-based selection, screening and rational design, unique pyrrolysyl-tRNA synthetase variants were successfully evolved for each of the three non-canonical amino acids, which enabled efficient production of recombinant proteins. Through encoding these ncAAs, we examined the deacylase activities of mammalian sirtuins to these modifications, and importantly we unfold the lipoamidase activity of several sirtuins.
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Aminoacil-tRNA Sintetases , Sirtuínas , Aminoácidos/metabolismo , Aminoacil-tRNA Sintetases/metabolismo , Animais , Escherichia coli/genética , Escherichia coli/metabolismo , Lipoilação , Lisina/metabolismo , Mamíferos/metabolismo , Processamento de Proteína Pós-Traducional , Proteômica , Proteínas Recombinantes/genética , Sirtuínas/metabolismoRESUMO
The exploitation of mineral resources may cause the environmental release of radionuclides and their introduction in the human trophic chain, affecting public health in the short and long term. A case study of the environmental radiation impact from coal mining and germanium processing was carried out in southwest China. The coal mines contain germanium and uranium and have been exploited for more than 40 years. The farmlands around the site of the coal mining and germanium processing have been contaminated by the solid waste and mine water to some extent since then. Samples of crops were collected from contaminated farmlands in the research area. The research area covers a radius of 5 km, in which there are two coal mines. 210Pb and 210Po were analyzed as the key radionuclides during the monitoring program. The average activity concentrations of 210Pb and 210Po in the crops were 1.38 and 1.32 Bq/kg in cereals, 4.07 and 2.19 Bq/kg in leafy vegetables and 1.63 and 1.32 Bq/kg in root vegetables. The annual effective doses due to the ingestion of 210Pb and 210Po in consumed crops were estimated for adult residents living in the research area. The average annual effective dose was 0.336 mSv/a, the minimum was 0.171 mSv/a and the maximum was 0.948 mSv/a. The results show that the crops grown on contaminated farmland contained an enhanced level of radioactivity concentration. The ingestion doses of local residents in the research area were significantly higher than the average level of 0.112 mSv/a in China, and the world average level of 0.042 mSv/a through 210Pb and 210Po in crop intake, respectively.
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Minas de Carvão , Germânio , Adulto , Carvão Mineral , Produtos Agrícolas , Ingestão de Alimentos , Humanos , Chumbo , Polônio , Radioisótopos/análiseRESUMO
Protein glycosylation plays critical roles in many biological processes. However, the fundamental study and application of glycobiology are hindered by the heterogeneousness of oligosaccharides in natural glycoproteins and the difficulty in constructing glycoproteins of human design. Herein, we describe a semisynthetic method to site-specifically modify proteins with reducing carbohydrates. The method involves the genetic incorporation of a side-chain-esterified aspartate, which was subsequently quantitatively converted into alanine-ß-hydrazide (Aßz), and chemoselective conjugation of Aßz with a range of readily available reducing carbohydrates. The resulting Aßz-linked GlcNAc is a close mimic of native N-GlcNAc and could be installed on various proteins, including IL-17A and RNase A. Notably, Aßz-linked GlcNAc on proteins reacted with biantennary oligosaccharide oxazoline derivatives through endoglycosidase-catalyzed transglycosylation reactions to enable the assembly of homogeneous glycans on proteins.
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Glicoproteínas , Oligossacarídeos , Glicoproteínas/metabolismo , Glicosilação , Humanos , Oligossacarídeos/metabolismo , Polissacarídeos/metabolismo , Processamento de Proteína Pós-TraducionalRESUMO
In poultry, feed restriction is common feeding management to limit poultry nutrients intake so that poultry only intake the essential energy, meeting the basic need of growth and development. Our study investigated whether feeding restriction affects the diversity of the intestinal microbiota of growing breeding ducks. In this research, the 60-120-day-old ducks were raised in restricted and free-feeding groups. After slaughtering, the carcass traits and the cecal contents were collected for 16S rRNA sequencing analysis. After feeding restriction, the growth rate of ducks was limited, the weight and rate of abdominal fat decreased, and the rate of chest and leg muscles increased. In addition, feeding restriction can also change the diversity of intestinal microorganisms in breeding ducks, such as the increase of Firmicutes abundance and the decrease of Bacteroidetes abundance. After analyzing of correlation, significant correlations between gut microbiota and carcass phenotypes were found. The results indicated that gut microbiota might be involved in the life activities associated with phenotypic changes. This study proved the effect of feeding methods on the intestinal microbiota of ducks, providing a theoretical basis of the microbial angle for raising ducks in a feeding-restricted period.
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Microbioma Gastrointestinal , Microbiota , Ração Animal/análise , Animais , Patos , Intestinos , RNA Ribossômico 16S/genéticaRESUMO
In this paper, we propose a radio-over-fiber system with no filters and generate 80 and 160 GHz millimeter (mm) waves via two Mach-Zehnder modulators (MZMs). The two MZMs, biased at the maximum transmission point, are used to suppress odd-order sidebands. By controlling the phase difference between the RF driving signal of the two MZMs, the $\pm({4}{n - 2})$-order is canceled. By adjusting the optical attenuator and phase shifter, the 0-order sideband is canceled, so only the $\pm 4{n}$-order sidebands are left. The simulation results show that using a 10 GHz RF signal to drive the MZMs, we obtain an 80 GHz mm wave signal with a 36.59 dB optical sideband suppression ratio (OSSR), a 30.27 dB radio frequency sideband suppression ratio (RFSSR), and a 160 GHz mm wave signal with a 30.34 dB OSSR and 24.77 dB RFSSR. The results are consistent with the theoretical analysis. Because no optical filter is employed and only two MZMs are used, the system exhibits a simple structure, good performance and is low cost.
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In recent years, remote sensing images has become one of the most popular directions in image processing. A small feature gap exists between satellite and natural images. Therefore, deep learning algorithms could be applied to recognize remote sensing images. We propose an improved Mask R-CNN model, called SCMask R-CNN, to enhance the detection effect in the high-resolution remote sensing images which contain the dense targets and complex background. Our model can perform object recognition and segmentation in parallel. This model uses a modified SC-conv based on the ResNet101 backbone network to obtain more discriminative feature information and adds a set of dilated convolutions with a specific size to improve the instance segmentation effect. We construct WFA-1400 based on the DOTA dataset because of the shortage of remote sensing mask datasets. We compare the improved algorithm with other state-of-the-art algorithms. The object detection AP50 and AP increased by 1-2% and 1%, respectively, objectively proving the effectiveness and the feasibility of the improved model.
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Hydrolysis characteristics of a novel 3,4-dichloroisothiazole based fungicide with activating plant defense responses as a candidate plant-activator LY5-24-2 were investigated under different conditions (pH and temperature) using ultra-performance liquid chromatography (UPLC) and quadrupole Time-of-Flight (Q-TOF). The hydrolysis case complied with the first-order kinetic model, with half-lives ranging from 4.8 h to 3.2 days at pH 4, 7, 9 and temperature at 25 and 50â. One of the hydrolysis metabolite 3,4-dichloroisothiazole-5-carboxylic acid (metabolite 1, M1) was determined and quantified using authentic standard. The other hydrolysate 3-chloro-5-(trifluoromethyl) pyridin-2-amine (metabolite 2, M2) was determined and identified according to accurate mass information, fragmentation patterns and principle component analysis (PCA). By utilizing high-resolution mass spectrometry and multivariate statistical analysis, hydrolysis dynamic of the metabolites was characterized and figured out. This research provided a non-target screening method to analyze hydrolysis metabolites of a new plant-activator and to find its degradation products in aqueous solution.
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Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Hidrólise , Cinética , Espectrometria de MassasRESUMO
MAIN CONCLUSION: Co-expression and regulatory networks yield important insights into the growth-defense tradeoffs mechanism under jasmonic acid (JA) signals in Arabidopsis. Elevated defense is commonly associated with growth inhibition. However, a comprehensive atlas of the genes associated with the plant growth-defense tradeoffs under JA signaling is lacking. To gain an insight into the dynamic architecture of growth-defense tradeoffs, a coexpression network analysis was employed on publicly available high-resolution transcriptomes of Arabidopsis treated with coronatine (COR), a mimic of jasmonoyl-l-isoleucine. The genes involved in JA-mediated growth-defense tradeoffs were systematically revealed. Promoter enrichment analysis revealed the core regulatory module in which the genes underwent rapid activation, sustained upregulation after COR treatment, and mediated the growth-defense tradeoffs. Several transcription factors (TFs), including RAP2.6L, MYB44, WRKY40, and WRKY18, were identified as instantly activated components associated with pathogen and insect resistance. JA might rapidly activate RAV1 and KAN1 to repress brassinosteroid (BR) response genes, upregulate KAN1, the C2H2 TF families ZF2, ZF3, ZAT6, and STZ/ZAT10 to repress the biosynthesis, transport, and signaling of auxin to arrest growth. Independent datasets and preserved analyses validated the reproducibility of the results. Our study provided a comprehensive snapshot of genes that respond to JA signals and provided valuable resources for functional studies on the genetic modification of breeding population that exhibit robust growth and defense simultaneously.
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Arabidopsis/metabolismo , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Aminoácidos/farmacologia , Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Indenos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Design of hybrid systems for photocatalytic application tends to be restricted by lacking interfacial coupling and fast charge recombination in the body competing with interface dynamics. In this work, the reduced carbon dots (rCDs) with numerous surface hydroxyl groups were deliberately anchored onto flower-like ZnO spheres with a highly exposed surface area to form heterointerfaces with sufficient interfacial electronic coupling. The incorporated rCDs evidently promote the light harvesting and charge separation of the binary hybrid system, resulting in highly enhanced photocatalytic Cr(VI) degradation performance. Ultrafast time-resolved spectra reveal that the surface C-OH bonds of rCDs play a crucial role at the heterointerfaces to regulate the charge dynamics. The long-lived surface C-OH states not only act as electron donors but also become electron mediators to rapidly capture the photoelectrons from the intrinsic state in the time-domain of 1 ps and induce a much longer lifetime for achieving highly efficient photoelectron injection from rCDs to ZnO. These results manifest that rCDs can be a promising photosensitizer to apply in photocatalytic pollutant treatment and energy conversion fields.
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The wide range, complex background, and small target size of aerial remote sensing images results in the low detection accuracy of remote sensing target detection algorithms. Traditional detection algorithms have low accuracy and slow speed, making it difficult to achieve the precise positioning of small targets. This paper proposes an improved algorithm based on You Only Look Once (YOLO)-v3 for target detection of remote sensing images. Due to the difficulty in obtaining the datasets, research on small targets for complex images, such as airplanes and ships, is the focus of research. To make up for the problem of insufficient data, we screen specific types of training samples from the DOTA (Dataset of Object Detection in Aerial Images) dataset and select small targets in two different complex backgrounds of airplanes and ships to jointly evaluate the optimization degree of the improved network. We compare the improved algorithm with other state-of-the-art target detection algorithms. The results show that the performance indexes of both datasets are ameliorated by 1-3%, effectively verifying the superiority of the improved algorithm.
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A new series of 3,6-diaryl-1H-pyrazolo[3,4-b]pyridine compounds have been discovered as potent anaplastic lymphoma kinase (ALK) inhibitors. The 4-hydroxyphenyl in the 6-position of 1H-pyrazolo[3,4-b]pyridine were crucial and a fluorine atom substitution could give promising inhibitory activity. The IC50 of compound 9v against ALK was up to 1.58â¯nM and a binding mechanism was proposed.
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Quinase do Linfoma Anaplásico/antagonistas & inibidores , Antineoplásicos/farmacologia , Piridinas/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Humanos , Ligação Proteica , Piridinas/químicaRESUMO
We report the γ-ray ionizing radiation response of commercial off-the-shelf (COTS) monolithic active-pixel sensors (MAPS) with different integration times and gains. The distribution of the eight-bit two-dimensional matrix of MAPS output frame images was studied for different parameter settings and dose rates. We present the first results of the effects of these parameters on the response of the sensor and establish a linear relationship between the average response signal and radiation dose rate in the high-dose rate range. The results show that the distribution curves can be separated into three ranges. The first range is from 0 to 24, which generates the first significant low signal peak. The second range is from 25 to 250, which shows a smooth gradient change with different integration times, gains, and dose rates. The third range is from 251 to 255, where a final peak appears, which has a relationship with integral time, gain, and dose rate. The mean pixel value shows a linear dependence on the radiation dose rate, albeit with different calibration constants depending on the integration time and gain. Hence, MAPS can be used as a radiation monitoring device with good precision.
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Graphitic carbon nitride (g-C3N4, CN) has garnered considerable attention in the field of photocatalysis due to its favorable band gap and high specific surface area. However, its primary practical limitation lies in the strong radiative recombination of lone pair (LP) electronic states, leading to limited efficiency in separating photogenerated carriers and subsequently diminishing photocatalytic performance. In this study, we devised and synthesized a heterojunction photocatalytic system comprising TiO2 nanosheets supported on modified g-C3N4 (MCN), designated as MCN/TiO2. The presence of CN functional groups on the tri-s-triazine nitrogen captures photogenerated electrons by modifying LP electronic states, resulting in a reduction in the fluorescence emission intensity of g-C3N4. Simultaneously, it forms chemical bonds with the supported TiO2 nanosheets, creating an efficient electron transfer pathway for the accumulation of photogenerated electrons at the active Ti sites. Experimentally, the MCN/TiO2 photocatalytic system exhibited optimal performance in CO2 reduction. The CH4 production rate reached 26.59 µmol g-1 h-1, surpassing that of TiO2 and CN/TiO2 by approximately 8 and 3 times, respectively. Furthermore, this photocatalytic system demonstrated exceptional photostability over five cycles, each lasting 4 h. This research offers a valuable approach for the efficient separation and transfer of photogenerated carriers in composite materials based on g-C3N4.
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Background: Mycoplasma pneumoniae (MP) is a significant cause of community-acquired pneumonia with high macrolide resistance rates. Various COVID-19 pandemic restrictions have impacted the prevalence of MP. Objective: To assess the changes in the pattern of MP infections among children before, during, and after the COVID-19 pandemic. Methods: A total of 36685 enrolled patients, aged 0-18 years, diagnosed with pneumonia and admitted to Children's Hospital of Chongqing Medical University from January 2019 to December 2023, were retrospectively reviewed in this study. The epidemiological characteristics of pediatric MP infection were analyzed. Results: Among 36685 patients, 7610 (20.74%) tested positive for MP. The highest positive rate was observed among children aged over 6 years (55.06%). There was no gender disparity in MP infection across the three phases of the COVID-19 pandemic. Hospital stays were longest for children during the COVID-19 pandemic (P <0.001). MP infection was most prevalent in the summer (29.64%). The lowest positive rate was observed during the pandemic, with the highest rate found after easing the measures across all age groups (P <0.001). There was a surge in the positive rate of MP in the third year after the COVID-19 pandemic. Regression analyses demonstrated a shift in the age range susceptible to MP infection, with children aged 3.8 to 13.5 years post-pandemic compared to the pre-pandemic range of 5.3 to 15.5 years old. Additionally, the average macrolide resistance rate was 79.84%. We observed a higher resistance rate during the pandemic than in the pre- and post-pandemic phases (P <0.001). Conclusion: The restrictive measures implemented during the COVID-19 pandemic have influenced the spread of MP to some extent and altered demographic and clinical characteristics, such as age, age group, season, length of stay, and macrolide resistance. We recommend continuous surveillance of the evolving epidemiological characteristics of MP infection in the post-pandemic period when restrictions are no longer necessary.