RESUMEN
ConspectusSingle atom electrocatalysts, with noble metal-free composition, maximal atom efficiency, and exceptional reactivity toward various energy and environmental applications, have become a research hot spot in the recent decade. Their simplicity and the isolated nature of the atomic structure of their active site have also made them an ideal model catalyst system for studying reaction mechanisms and activity trends. However, the state of the single atom active sites during electrochemical reactions may not be as simple as is usually assumed. To the contrary, the single atom electrocatalysts have been reported to be under greater influence from interfacial dynamics, with solvent and electrolyte ions perpetually interacting with the electrified active center under an applied electrode potential. These complexities render the activity trends and reaction mechanisms derived from simplistic models dubious.In this Account, with a few popular single atom electrocatalysis systems, we show how the change in electrochemical potential induces nontrivial variation in the free energy profile of elemental electrochemical reaction steps, demonstrate how the active centers with different electronic structure features can induce different solvation structures at the interface even for the same reaction intermediate of the simplest electrochemical reaction, and discuss the implication of the complexities on the kinetics and thermodynamics of the reaction system to better address the activity and selectivity trends. We also venture into more intriguing interfacial phenomena, such as alternative reaction pathways and intermediates that are favored and stabilized by solvation and polarization effects, long-range interfacial dynamics across the region far beyond the contact layer, and the dynamic activation or deactivation of single atom sites under operation conditions. We show the necessity of including realistic aspects (explicit solvent, electrolyte, and electrode potential) into the model to correctly capture the physics and chemistry at the electrochemical interface and to understand the reaction mechanisms and reactivity trends. We also demonstrate how the popular simplistic design principles fail and how they can be revised by including the kinetics and interfacial factors in the model. All of these rich dynamics and chemistry would remain hidden or overlooked otherwise. We believe that the complexity at an electrochemical interface is not a curse but a blessing in that it enables deeper understanding and finer control of the potential-dependent free energy landscape of electrochemical reactions, which opens up new dimensions for further design and optimization of single atom electrocatalysts and beyond. Limitations of current methods and challenges faced by the theoretical and experimental communities are discussed, along with the possible solutions awaiting development in the future.
RESUMEN
Electrocatalytic nitrogen oxide reduction (NOxRR) emerges as an effective way to bring the disrupted nitrogen cycle back into balance. However, efficient and selective NOxRR is still challenging partly due to the complex reaction mechanism, which is influenced by experimental conditions such as pH and electrode potential. Here, we have studied the enzyme-inspired iron single-atom catalysts (Fe-N4-C) and identified that the selectivity roots in the first step of the nitric oxide reduction. Combining the constrained molecular dynamics (MD) simulations with the quasi-equilibrium approximation, the effects of electrode potential and pH on the reaction free energy were considered explicitly and predicted quantitatively. Systematic heat maps for selectivity between single-N and N-N-coupled products in a wide pH-potential space are further developed, which have reproduced the experimental observations of NOxRR. The approach presented in this study allows for a realistic simulation of the electrocatalytic interfaces and a quantitative evaluation of interfacial effects. Our results in this study provide valuable and straightforward guidance for selective NOx reduction toward desired products by precisely designing the experimental conditions.
RESUMEN
Reactive metal-support interaction (RMSI) is an emerging way to regulate the catalytic performance for supported metal catalysts. However, the induction of RMSI by the thermal reduction is often accompanied by the encapsulation effect on metals, which limits the mechanism research and applications of RMSI. In this work, a gradient orbital coupling construction strategy was successfully developed to induce RMSI in Pt-carbide system without a reductant, leading to the formation of L12-PtxM-MCy (M = Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W) intermetallic electrocatalysts. Density functional theory (DFT) calculations suggest that the gradient coupling of the d(M)-2p(C)-5d(Pt) orbital would induce the electron transfer from M to C covalent bonds to Pt NPs, which facilitates the formation of C vacancy (Cv) and the subsequent M migration (occurrence of RMSI). Moreover, the good correlation between the formation energy of Cv and the onset temperature of RMSI in Pt-MCx systems proves the key role of nonmetallic atomic vacancy formation for inducing RMSI. The developed L12-Pt3Ti-TiC catalyst exhibits excellent acidic methanol oxidation reaction activity, with mass activity of 2.36 A mgPt-1 in half-cell and a peak power density of 187.9 mW mgPt-1 in a direct methanol fuel cell, which is one of the best catalysts ever reported. DFT calculations reveal that L12-Pt3Ti-TiC favorably weakens *CO absorption compared to Pt-TiC due to the change of the absorption site from Pt to Ti, which accounts for the enhanced MOR performance.
RESUMEN
Tuning the active site structure of metal-nitrogen-carbon electrocatalysts has recently attracted increasing interest. Herein, we report a bottom-up synthesis strategy in which atomically regulated N-doped polycyclic aromatic hydrocarbons (N-PAHs) of NxC42-x (x = 1, 2, 3, 4) were used as ligands to allow tuning of the active site's structures of M-Nx and establish correlations between the structures and electrocatalytic properties. Based on the synthesis process, detailed characterization, and DFT calculation results, active structures of Nx-Fe1-Nx in Fe1-Nx/RGO catalysts were constructed. The results demonstrated that the extra uncoordinated N atoms around the Fe1-N4 moieties disrupted the π-conjugated NxC42-x ligands, which led to more localized electronic state in the Fe1-N4 moieties and superior catalytic performance. Especially, the Fe1-N4/RGO exhibited optimized performance for ORR with E1/2 increasing by 80 mV and Jk at 0.85 V improved 18 times (compared with Fe1-N1/RGO). This synthesis strategy utilizing N-PAHs holds significant promise for enhancing the controllability of metal-nitrogen-carbon electrocatalyst preparation.
RESUMEN
Human infertility is a multifactorial disease that affects 8%-12% of reproductive-aged couples worldwide. However, the genetic causes of human infertility are still poorly understood. Synaptonemal complex (SC) is a conserved tripartite structure that holds homologous chromosomes together and plays an indispensable role in the meiotic progression. Here, we identified three homozygous mutations in the SC coding gene C14orf39/SIX6OS1 in infertile individuals from different ethnic populations by whole-exome sequencing (WES). These mutations include a frameshift mutation (c.204_205del [p.His68Glnfs∗2]) from a consanguineous Pakistani family with two males suffering from non-obstructive azoospermia (NOA) and one female diagnosed with premature ovarian insufficiency (POI) as well as a nonsense mutation (c.958G>T [p.Glu320∗]) and a splicing mutation (c.1180-3C>G) in two unrelated Chinese men (individual P3907 and individual P6032, respectively) with meiotic arrest. Mutations in C14orf39 resulted in truncated proteins that retained SYCE1 binding but exhibited impaired polycomplex formation between C14ORF39 and SYCE1. Further cytological analyses of meiosis in germ cells revealed that the affected familial males with the C14orf39 frameshift mutation displayed complete asynapsis between homologous chromosomes, while the affected Chinese men carrying the nonsense or splicing mutation showed incomplete synapsis. The phenotypes of NOA and POI in affected individuals were well recapitulated by Six6os1 mutant mice carrying an analogous mutation. Collectively, our findings in humans and mice highlight the conserved role of C14ORF39/SIX6OS1 in SC assembly and indicate that the homozygous mutations in C14orf39/SIX6OS1 described here are responsible for infertility of these affected individuals, thus expanding our understanding of the genetic basis of human infertility.
Asunto(s)
Azoospermia/genética , Mutación , Insuficiencia Ovárica Primaria/genética , Adulto , Azoospermia/fisiopatología , Emparejamiento Cromosómico , Codón sin Sentido , Proteínas de Unión al ADN/metabolismo , Femenino , Homocigoto , Humanos , Masculino , Meiosis , Persona de Mediana Edad , Proteínas Nucleares/metabolismo , Linaje , Insuficiencia Ovárica Primaria/fisiopatología , Espermatocitos/metabolismo , Espermatocitos/fisiología , Complejo Sinaptonémico/genética , Complejo Sinaptonémico/metabolismo , Secuenciación Completa del GenomaRESUMEN
Cuproptosis is a novel copper-dependent form of programmed cell death, displaying important regulatory functions in many human diseases, including cancer. However, the relationship between the changes in mitochondrial viscosity, a key factor associated with cellular malfunction, and cuproptosis is still unclear. Herein, we prepared a phosphorescent iridium (Ir) complex probe for precisely monitoring the changes of mitochondrial viscosity during cuprotosis via phosphorescence lifetime imaging. The Ir complex probe possessed microsecond lifetimes (up to 1 µs), which could be easily distinguished from cellular autofluorescence to improve the imaging contrast and sensitivity. Benefiting from the long phosphorescence lifetime, excellent viscosity selectivity, and mitochondrial targeting abilities, the Ir complex probe could monitor the increase in the mitochondrial viscosity during cuproptosis (from 46.8 to 68.9 cP) in a quantitative manner. Moreover, through in situ fluorescence imaging, the Ir complex probe successfully monitored the increase in viscosity in zebrafish treated with lipopolysaccharides or elescolomol-Cu2+, which were well-known cuproptosis inducers. We anticipate that this new Ir complex probe will be a useful tool for in-depth understanding of the biological effects of mitochondrial viscosity during cuproptosis.
Asunto(s)
Iridio , Pez Cebra , Animales , Humanos , Viscosidad , Pez Cebra/metabolismo , Línea Celular Tumoral , Células HeLaRESUMEN
The practical application of the room-temperature sodium-sulfur (RT Na-S) batteries is currently limited by low reversible capacity and serious capacity decay due to the sluggish reaction kinetics and shuttle effect. It is necessary to design a suitable sulfur host integrated with electrocatalysts to realize effective chemisorption and catalysis of sodium polysulfides (NaPSs). Herein, under the guidance of theoretical calculation, the Mott-Schottky heterojunction with a built-in electric field composed of iron (Fe) and iron disulfide (FeS2) components anchored on a porous carbon matrix (Fe/FeS2-PC) is designed and prepared. The enhanced chemisorption effect of Fe, the fast electrocatalytic effect of FeS2, and the fast transfer effect of the built-in electric field within the Fe/FeS2 heterojunction in the cathode of RT Na-S batteries work together to effectively improve the electrochemical performance. As a result, the Fe/FeS2-PC@S cathode exhibits high reversible capacity (815 mAh g-1 after 150 cycles at 0.2 A g-1) and excellent stability (516 mAh g-1 after 600 cycles at 5 A g-1, with only 0.07% decay per cycle). The design of the Fe/FeS2 heterojunction electrocatalyst provides a new strategy for the development of highly stable RT Na-S batteries.
RESUMEN
Vitamin D receptors and vitamin D3-metabolizing enzymes have been found to be highly expressed in the ovaries and spermatophores of fish. However, the role of vitamin D3 on fish gonadal development has rarely been reported. In this study, 2-month-old female zebrafish were fed with different concentrations of vitamin D3 diets (0, 700, 1400, and 11 200 IU/kg) to investigate the effects of vitamin D3 on ovarian development. The diet with 0 IU/kg vitamin D3 resulted in elevated interstitial spaces, follicular atresia, and reproductive toxicity in zebrafish ovaries. Supplementation with 700 and 1400 IU/kg of vitamin D3 significantly increased the oocyte maturation rate; upregulated ovarian gonadal steroid hormone synthesis capacity; and elevated plasma estradiol, testosterone, and ovarian vitellogenin levels. Furthermore, the current study identified a vitamin D response element in the cyp19a1a promoter and demonstrated that 1.25(OH)2D3-vitamin D response directly activated cyp19a1a production through activating the vitamin D response element. In conclusion, this study shows that an appropriate concentration of vitamin D3 can promote zebrafish ovarian development and affect vitellogenin synthesis through the vdr/cyp19a1a/er/vtg gene axis.
Asunto(s)
Colecalciferol , Pez Cebra , Animales , Femenino , Colecalciferol/farmacología , Vitelogeninas/genética , Atresia Folicular , Vitamina D , Hormonas Esteroides Gonadales , OocitosRESUMEN
Aiming at the problem of luminance uniformity for injection electroluminescent display panels, we present a new sample compensation method based on column-control according to successive scans theory. On the basis of our ideas, a small part of pixels of each column are selected as samples, and the column gating time calculated by sample average luminance value of corresponding column is written in hardware program. We adopt the 64 × 32 LEDs display panel as an example to expound the compensation method and obtain good result that the reduction in amplitude of luminance non-uniformity is 65.42% for the sample area, 58.67% for the non-sample area and 60.21% for the entire display panel.
RESUMEN
Human epidermal growth factor receptor 2 (HER2) is a transmembrane glycoprotein receptor with intracellular tyrosine kinase activity. It is generally considered as a poor prognostic marker. Targeted therapies, such as small molecule tyrosine kinase inhibitors (TKIs), showed limited efficacy in HER2-mutant advanced nonsmall cell lung cancer (NSCLC). In the 2023 National Comprehensive Cancer Network guidelines for NSCLC, antibody-drug conjugate trastuzumab emtansine is recommended for the treatment of HER2-mutant lung cancer. However, this medication is currently not approved in certain regions. So it is necessary to explore alternative treatment options for HER2-mutant NSCLC patients. In our study of a patient with HER2 exon 20 insertion lung adenocarcinoma who had previously failed multiple epidermal growth factor receptor (EGFR)-TKI treatments, we discovered that sunvozertinib could stabilize the patient's condition, achieving a progression-free survival of 87 days. This is a novel finding that may provide new treatment options for HER2 exon 20 insertion patients who have failed TKI therapy.
Asunto(s)
Adenocarcinoma del Pulmón , Exones , Neoplasias Pulmonares , Receptor ErbB-2 , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Receptor ErbB-2/genética , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Inhibidores de Proteínas Quinasas/uso terapéutico , Femenino , Persona de Mediana Edad , Masculino , Quinolinas/uso terapéuticoRESUMEN
BACKGROUND: Catheter ablation is recommended in patients with frequent and symptomatic ventricular arrhythmias (VAs) in an otherwise normal heart. Right or left outflow tract (OT) are the most common origins, and catheter ablation is highly effective with low complication rates. However, outcome of catheter ablation of VAs other than the OT (non-OTVAs) is limited. The aim of this single-center study was to assess the safety and mid-term outcome of catheter ablation for non-OTVAs. METHOD AND RESULTS: From 2013 to 2018, 251 patients who underwent catheter ablation for idiopathic non-OTVAs were enrolled and grouped according to the origins including His-Purkinje system (HPS, n = 108), papillary muscle / moderator band (PM/MB, n = 47), tricuspid annulus (TA, n = 70), and mitral annulus (MA, n = 26), 244 (97.2%) had acute elimination of VAs. The time of VAs recurrence of the single procedure was 1.69 (0.12,9.72) months, with 66% occurring within the first 3 months. The recurrence rate was significantly higher in the PM/MB group than in the TA (p = 0.025) and MA groups (p = 0.023). The single procedure success rate in all patients was 70.1%, in which 66.7%, 59.6%, 80%, and 76.9% were achieved in the HPS, PM/MB, TA, and MA groups, respectively (p = 0.284). After multiple procedures, the total success rate was 76.5% at the follow-up of 4.38 ± 2.42 years. The rate was significantly lower in the PM/MB group than in the TA group (p = 0.035). In subgroup analysis, no significant difference was observed in the recurrence rate of single procedure in patients with different VA origins within the PM/MB (log-rank test, p = 0.546). CONCLUSION: Despite a certain percentage of recurrences observed in the mid-term follow-up, catheter ablation remained feasible and effective for idiopathic non-OTVAs.
Asunto(s)
Ablación por Catéter , Músculos Papilares , Humanos , Ventrículos Cardíacos , Arritmias Cardíacas , Ablación por Catéter/efectos adversos , Válvula MitralRESUMEN
The catalytic hydrogenation of biomass-derived chemicals is essential in chemical industry due to the growing demand for sustainable and renewable energy sources. In this study, we present a comprehensive theoretical investigation regarding the hydrogenation of glycolaldehyde to ethylene glycol over a Ru/C catalyst by employing density functional theory and ab initio molecular dynamics simulations. With inclusion of explicit solvation, we have demonstrated that the glycolaldehyde hydrogenation is significantly improved due to the fast proton transfer through the hydrogen bond network. The enhanced activity could be attributed to the participation of the solvent water as the hydrogen source and the highly positively charged state of a Ru cluster in an aqueous phase, which are critical for the activation of aldehyde groups and proton-assisted hydrogenation. Overall, our findings provide valuable insights into glycolaldehyde hydrogenation over Ru/C catalysts in the aqueous phase, highlighting the importance of solvation effects in the biomass conversion.
RESUMEN
KEY MESSAGE: Cathepsin B plays an important role that degrades the Rubisco large subunit RbcL in freezing stress. Programmed cell death (PCD) has been well documented in both development and in response to environmental stresses in plants, however, PCD induced by freezing stress and its molecular mechanisms remain poorly understood. In the present study, we characterized freezing-induced PCD and explored its mechanisms in Arabidopsis. PCD induced by freezing stress was similar to that induced by other stresses and senescence in Arabidopsis plants with cold acclimation. Inhibitor treatment assays and immunoblotting indicated that cathepsin B mainly contributed to increased caspase-3-like activity during freezing-induced PCD. Cathepsin B was involved in freezing-induced PCD and degraded the large subunit, RbcL, of Rubisco. Our results demonstrate an essential regulatory mechanism of cathepsin B for Rubisco degradation in freezing-induced PCD, improving our understanding of freezing-induced cell death and nitrogen and carbohydrate remobilisation in plants.
Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Catepsina B/metabolismo , Congelación , Ribulosa-Bifosfato Carboxilasa/metabolismo , Apoptosis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismoRESUMEN
Aeromonas dhakensis is reported as an emerging pathogenic species within the genus Aeromonas and is widely distributed in tropical coastal areas. This study provided a detailed description and characterization of a strain of A. dhakensis (202108B1) isolated from diseased Ancherythroculter nigrocauda in an inland region of China. Biochemical tests identified the isolate at the genus level, and the further molecular analysis of concatenated housekeeping gene sequences revealed that the strain belonged to the species A. dhakensis. The isolated A. dhakensis strain was resistant to five antibiotics, namely, penicillin, ampicillin, clindamycin, cephalexin, and imipenem, while it was susceptible to or showed intermediate resistance to most of the other 15 tested antibiotics. The isolated strain of A. dhakensis caused acute hemorrhagic septicemia and tissue damage in artificially infected A. nigrocauda, with a median lethal dose of 7.76 × 104 CFU/fish. The genome size of strain 202108B1 was 5 043 286 bp, including 1 chromosome and 4 plasmids. This is the first detailed report of the occurrence of infection caused by an A. dhakensis strain causing infection in an aquaculture system in inland China, providing important epidemiological data on this potential pathogenic species.
Asunto(s)
Aeromonas , Antibacterianos , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , China , Aeromonas/genética , Aeromonas/aislamiento & purificación , Aeromonas/clasificación , Aeromonas/efectos de los fármacos , Aeromonas/patogenicidad , Animales , Antibacterianos/farmacología , Enfermedades de los Peces/microbiología , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/veterinaria , Peces/microbiología , Filogenia , Pruebas de Sensibilidad Microbiana , Acuicultura , Genoma Bacteriano , ARN Ribosómico 16S/genética , Plásmidos/genéticaRESUMEN
Non-small cell lung cancer (NSCLC) is the primary inducer of cancer-related death worldwide. Asiaticoside (ATS) is a triterpenoid saponin that has been indicated to possess an antitumor activity in several malignancies. Nonetheless, its detailed functions in NSCLC remain unclarified. In this study, NSCLC cells were exposed to various doses of ATS. Functional experiments were employed to estimate the ATS effect on NSCLC cell behaviors. Western blotting was implemented for protein expression evaluation. A xenograft mouse model was established to assess the ATS effect on NSCLC in vivo. The results showed that ATS restrained NSCLC cell proliferation, cell cycle progression, migration, and invasiveness. ATS reversed TGF-ß-induced promotion in epithelial-mesenchymal transition (EMT). Mechanistically, ATS inhibited Wnt/ß-catenin signaling in NSCLC. Upregulating ß-catenin restored ATS-mediated suppression of NSCLC cell aggressiveness. Moreover, ATS administration repressed tumorigenesis in tumor-bearing mice. In conclusion, ATS represses growth and metastasis in NSCLC by blocking EMT via the inhibition of Wnt/ß-catenin signaling.
RESUMEN
In this paper, we proposed a stepping equivalent range-gate method (S-ERG method) to measure the speed and the distance of the moving target for range-gated imaging lidar. In this method, the speed is obtained by recording the time at which the moving target passes the front and back edges of the range gate, the distance information can also be obtained by the front and back edges of the range gate at the same time. To verify the feasibility of this method, a stationary target and a moving target with different speeds were measured by the S-ERG method. By using the S-ERG method, we not only obtained the distance information of the stationary target and the moving target at the front and back edges of the range gate, respectively, but also obtained the speed of the moving target. Compared to speeds measured by rotational displacement sensors, the speed measurement error of the S-ERG method is less than 5%, whether the target is far away or close to the range-gated lidar system, and this method is almost independent of the delay step time. The theoretical analysis and experimental results indicate range-gated imaging lidar using the S-ERG method has high practicality and wide applications.
RESUMEN
The presence of defects in substation equipment is a major factor affecting the safety of power transmission. Therefore, timely and accurate detection of these defects is crucial. As intelligent inspection robots advance, using mainstream object detection models to diagnose surface defects in substation equipment has become a focal point of current research. However, the lack of defect image data is one of the main factors affecting the accuracy of supervised deep learning-based defect detection models. To address the issue of insufficient training data for defect images with complex backgrounds, such as rust and surface oil leakage in substation equipment, which leads to the poor performance of detection models, this paper proposes a novel adversarial deep learning model for substation defect image generation: the Abnormal Defect Detection Generative Adversarial Network (ADD-GAN). Unlike existing generative adversarial networks, this model generates defect images based on effectively segmented local areas of substation equipment images, avoiding image distortion caused by global style changes. Additionally, the model uses a joint discriminator for both overall images and defect images to address the issue of low attention to local defect areas, thereby reducing the loss of image features. This approach enhances the overall quality of generated images as well as locally generated defect images, ultimately improving image realism. Experimental results demonstrate that the YOLOV7 object detection model trained on the dataset generated using the ADD-GAN method achieves a mean average precision (mAP) of 81.5% on the test dataset, and outperforms other image data augmentation and generation methods. This confirms that the ADD-GAN method can generate a high-fidelity image dataset of substation equipment defects.
RESUMEN
BACKGROUND: The excessive salt intake associated with Douchi has become a topic of controversy. Addressing this concern and enhancing its market competitiveness necessitates the application of salt reduction fermentation in Douchi. Therefore, to promote the application of salt reduction fermentation in Douchi, a comprehensive study was undertaken aiming to investigate the differences in biogenic amines, volatile compounds and non-volatile compounds in Douchi with varying salt content. RESULTS: The findings unequivocally demonstrate that salt hampers the formation of metabolites in Douchi. As the salt content increased, there was a significant decrease (P < 0.05) in the levels of total acid, amino-type nitrogen and free amino acids in Douchi. Notably, when the salt content exceeded 80 g kg-1, there was a substantial reduction (P < 0.05) in putrescine, lactic acid and malic acid levels. Similarly, when the salt content surpassed 40 g kg-1, ß-phenethylamine and oxalic acid levels exhibited a significant decline (P < 0.05). Furthermore, the results of E-nose and principal component analysis based on headspace solid phase microextraction gas chromatography-mass spectrometry revealed notable discrepancies in the volatile compound content between Douchi samples with relatively low salt content (40 and 80 g kg-1) and those with relatively high salt content (120, 160 and 200 g kg-1) (P < 0.05). By employing partial least squares discriminant analysis, eight distinct volatile compounds, including o-xylene, benzaldehyde and 1-octen-one, were identified. These compounds exhibited higher concentrations in Douchi samples with relatively low salt content (40 and 80 g kg-1). The sensory results showed that Douchi samples with lower salt content exhibited higher scores in the soy sauce-like and Douchi aroma attributes. CONCLUSION: In conclusion, this study significantly enhances our understanding of the impact of salt on metabolites in Douchi and provides invaluable insights for the development of salt reduction fermentation in this context. © 2024 Society of Chemical Industry.
Asunto(s)
Aminas Biogénicas , Fermentación , Cromatografía de Gases y Espectrometría de Masas , Compuestos Orgánicos Volátiles , Aminas Biogénicas/análisis , Aminas Biogénicas/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Compuestos Orgánicos Volátiles/química , Compuestos Orgánicos Volátiles/análisis , Cloruro de Sodio/análisis , Cloruro de Sodio/metabolismoRESUMEN
A 60-day feeding trial was conducted to evaluate the impact of dietary Antarctic krill meal on the reproductive performance and embryo quality of the Chinese mitten crab, Eriocheir sinensis. Three diets were formulated, incorporating varying levels of Antarctic krill meal at 0% (Diet K0), 10% (Diet K10), and 20% (Diet K20), with a control group fed razor clam Sinonovacula constricta. Each diet was randomly assigned to three replicate tanks, each stocked with 5 males and 10 females. Male and female weights were 145.38 ± 8.01 and 102.57 ± 9.73 g, respectively. The results revealed no significant differences in weight gain rate, specific growth rate, and survival rate. However, the hepatopancreatic weight and hepatopancreas index of female crabs in each group decreased, while gonadal weight and gonadosomatic index increased significantly after 60 days, with Diet K20 showing the highest values. Egg production and fecundity of female crabs reached their peak in Diet K20, with no significant differences in reproductive indices among all groups. The phospholipid content in Diet K20 was significantly higher than in the other groups (P < 0.05). Cholesterol contents in Diet K0 and the control group were significantly higher than in Diet K10 and K20 (P < 0.05). No significant differences were observed in egg diameter, egg weight, moisture, crude protein, and crude fat between the groups. The content of C20 : 2 and C20 : 4n6 was highest in Diet K0, with a significant difference compared to Diet K10 (P < 0.05). However, no significant differences were found in the total content of saturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids among all groups. Based on the research findings, it is recommended that the optimal level of Antarctic krill meal in diets is 20%.
RESUMEN
Due to anthropogenic activities such as mining, several agricultural soils are polluted by multiple heavy metals. However, it is still unclear whether multiple heavy metals could affect the distribution of antibiotic resistance genes (ARGs), and how metals affect ARGs. To understand ARGs' distribution in heavy metal-polluted soils, we chose soils contaminated by different types and contents of heavy metals to determine the ARGs' number and abundance through high-throughput quantitative real-time PCR (HT-qPCR) in this study. Additionally, the factors affecting ARGs' distribution, such as soil properties, mobile genetic genes (MGEs), and bacterial communities, were explored. The results demonstrated that the sampled soils were primarily contaminated by Cd, As, Pb, and Zn, and the pollution load index (PLI) values of these metals ranged from 1.3 to 2.7, indicating a low to moderate degree of heavy metal contamination. The number and abundance of ARGs ranged from 44 to 113 and from 2.74 × 107 copies/g to 1.07 × 108 copies/g, respectively. Besides, abundant MGEs in soils, ranging from 1.84 × 106 copies/g to 5.82 × 106 copies/g, were observed. The pathway analysis suggested that MGEs were the most important factor directly affecting ARG abundance (0.89). Notably, heavy metals also affected the ARG abundance. Proteobacteria and Actinobacteria, the main heavy metal tolerant bacteria, were found to be the main hosts of ARGs through network analysis. ARG-carrying pathogens (ACPs) in agricultural soils were found to carry MGEs, indicating a high risk of dissemination. This study provided important information for understanding the ARGs' fate and also the key factors affecting ARGs' spread in multiple heavy metal-contaminated soils.