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Single-atom catalysis (SAC) attracts wide interest for zinc-air batteries that require high-performance bifunctional electrocatalysts for oxygen reactions. However, catalyst design is still highly challenging because of the insufficient driving force for promoting multiple-electron transfer kinetics. Herein, we report a superstructure-assisted SAC on tungsten carbides for oxygen evolution and reduction reactions. In addition to the usual single atomic sites, strikingly, we reveal the presence of highly ordered Co superstructures in the interfacial region with tungsten carbides that induce internal strain and promote bifunctional catalysis. Theoretical calculations show that the combined effects from superstructures and single atoms strongly reduce the adsorption energy of intermediates and overpotential of both oxygen reactions. The catalyst therefore presented impressive bifunctional activity with an ultralow potential gap of 0.623 V and delivered a high power density of 188.5 mW cm-2 for assembled zinc-air batteries. This work opens up new opportunities for atomic catalysis.
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Acute lung injury (ALI) is the pathophysiological precursor of acute respiratory distress syndrome. It is characterized by increased oxidative stress and exaggerated inflammatory response that disrupts redox reactions and immune homeostasis in the lungs, thereby posing significant clinical challenges. In this study, an internally functionalized thioether-enriched dendrimer Sr-G4-PEG is developed, to scavenge both proinflammatory cytokines and reactive oxygen species (ROS) and restore homeostasis during ALI treatment. The dendrimers are synthesized using an efficient and orthogonal thiol-ene "click" chemistry approach that involves incorporating thioether moieties within the dendritic architectures to neutralize the ROS. The ROS scavenging of Sr-G4-PEG manifests in its capacity to sequester proinflammatory cytokines. The synergistic effects of scavenging ROS and sequestering inflammatory cytokines by Sr-G4-PEG contribute to redox remodeling and immune homeostasis, along with the modulation of the NLRP3-pyroptosis pathway. Treatment with Sr-G4-PEG enhances the therapeutic efficacy of ALIs by alleviating alveolar bleeding, reducing inflammatory cell infiltration, and suppressing the release of inflammatory cytokines. These results suggest that Sr-G4-PEG is a potent nanotechnological candidate for remodeling redox and immune homeostasis in the treatment of ALIs, demonstrating the great potential of dendrimer-based nanomedicine for the treatment of respiratory pathologies.
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Nuclear hyperfine mixing (NHM) is a distinctive effect through which nuclear properties and dynamics can be efficiently controlled. Traditionally, the scientific consensus has predominantly associated NHM with its pronounced impact on ^{229}Th, owing to the existence of its low-lying isomeric state. However, in the present study, by developing a general theory for NHM, we predict a surprisingly substantial NHM effect in boronlike ^{205}Pb ions (specifically, ^{205}Pb^{77+}), featuring a nuclear transition energy of 2.329 keV. The radiative lifetime of the ^{205}Pb isomer is reduced by 4 orders of magnitude, from 15 min to 32 ms. This remarkable and unexpected NHM effect stems from a heretofore unexplored process: an opening of a magnetic dipole channel that is otherwise forbidden without NHM. ^{205}Pb ions now emerge as an attractive alternative candidate for experimental validation and investigation of the NHM effect.
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The kagome spin ice can host frustrated magnetic excitations by flipping its local spin. Under an inelastic tunneling condition, the tip in a scanning tunneling microscope can flip the local spin, and we apply this technique to kagome metal HoAgGe with a long-range ordered spin ice ground state. Away from defects, we discover a pair of pronounced dips in the local tunneling spectrum at symmetrical bias voltages with negative intensity values, serving as a striking inelastic tunneling signal. This signal disappears above the spin ice formation temperature and has a dependence on the magnetic fields, demonstrating its intimate relation with the spin ice magnetism. We provide a two-level spin-flip model to explain the tunneling dips considering the spin ice magnetism under spin-orbit coupling. Our results uncover a local emergent excitation of spin ice magnetism in a kagome metal, suggesting that local electrical field induced spin flip climbs over a barrier caused by spin-orbital locking.
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It is well known that information on stimulus orientation plays an important role in sensory processing. However, the neural mechanisms underlying somatosensory orientation perception are poorly understood. Adaptation has been widely used as a tool for examining sensitivity to specific features of sensory stimuli. Using the adaptation paradigm, we measured event-related potentials (ERPs) in response to tactile orientation stimuli presented pseudo-randomly to the right-hand palm in trials with all the same or different orientations. Twenty participants were asked to count the tactile orientation stimuli. The results showed that the adaptation-related N60 component was observed around contralateral central-parietal areas, possibly indicating orientation processing in the somatosensory regions. Conversely, the adaptation-related N120 component was identified bilaterally across hemispheres, suggesting the involvement of the frontoparietal circuitry in further tactile orientation processing. P300 component was found across the whole brain in all conditions and was associated with task demands, such as attention and stimulus counting. These findings help provide an understanding of the mechanisms of tactile orientation processing in the human brain.
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Eletroencefalografia , Percepção do Tato , Humanos , Potenciais Evocados/fisiologia , Tato/fisiologia , Encéfalo/fisiologia , Atenção/fisiologia , Percepção do Tato/fisiologiaRESUMO
INTRODUCTION: Distinguishing between malignant pleural effusion (MPE) and benign pleural effusion (BPE) poses a challenge in clinical practice. We aimed to construct and validate a combined model integrating radiomic features and clinical factors using computerized tomography (CT) images to differentiate between MPE and BPE. METHODS: A retrospective inclusion of 315 patients with pleural effusion (PE) was conducted in this study (training cohort: n = 220; test cohort: n = 95). Radiomic features were extracted from CT images, and the dimensionality reduction and selection processes were carried out to obtain the optimal radiomic features. Logistic regression (LR), support vector machine (SVM), and random forest were employed to construct radiomic models. LR analyses were utilized to identify independent clinical risk factors to develop a clinical model. The combined model was created by integrating the optimal radiomic features with the independent clinical predictive factors. The discriminative ability of each model was assessed by receiver operating characteristic curves, calibration curves, and decision curve analysis (DCA). RESULTS: Out of the total 1,834 radiomic features extracted, 15 optimal radiomic features explicitly related to MPE were picked to develop the radiomic model. Among the radiomic models, the SVM model demonstrated the highest predictive performance [area under the curve (AUC), training cohort: 0.876, test cohort: 0.774]. Six clinically independent predictive factors, including age, effusion laterality, procalcitonin, carcinoembryonic antigen, carbohydrate antigen 125 (CA125), and neuron-specific enolase (NSE), were selected for constructing the clinical model. The combined model (AUC: 0.932, 0.870) exhibited superior discriminative performance in the training and test cohorts compared to the clinical model (AUC: 0.850, 0.820) and the radiomic model (AUC: 0.876, 0.774). The calibration curves and DCA further confirmed the practicality of the combined model. CONCLUSION: This study presented the development and validation of a combined model for distinguishing MPE and BPE. The combined model was a powerful tool for assisting in the clinical diagnosis of PE patients.
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Derrame Pleural Maligno , Tomografia Computadorizada por Raios X , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Derrame Pleural Maligno/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Diagnóstico Diferencial , Derrame Pleural/diagnóstico por imagem , Máquina de Vetores de Suporte , Curva ROC , Modelos Logísticos , Adulto , RadiômicaRESUMO
To achieve precision in predicting an epidemic threshold in complex networks, we have developed a novel threshold graph neural network (TGNN) that takes into account both the network topology and the spreading dynamical process, which together contribute to the epidemic threshold. The proposed TGNN could effectively and accurately predict the epidemic threshold in homogeneous networks, characterized by a small variance in the degree distribution, such as Erdos-Rényi random networks. Usability has also been validated when the range of the effective spreading rate is altered. Furthermore, extensive experiments in ER networks and scale-free networks validate the adaptability of the TGNN to different network topologies without the necessity for retaining. The adaptability of the TGNN is further validated in real-world networks.
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KEY MESSAGE: Plant-deleterious microbial volatiles activate the transactivation of hypoxia, MAMPs and wound responsive genes in Arabidopsis thaliana. AtMKK1 and AtMKK3 are involved in the plant-deleterious microbial volatiles-induced defense responses. Microbial volatile compounds (mVCs) are a collection of volatile metabolites from microorganisms with biological effects on all living organisms. mVCs function as gaseous modulators of plant growth and plant health. In this study, the defense events induced by plant-deleterious mVCs were investigated. Enterobacter aerogenes VCs lead to growth inhibition and immune responses in Arabidopsis thaliana. E. aerogenes VCs negatively regulate auxin response and transport gene expression in the root tip, as evidenced by decreased expression of DR5::GFP, PIN3::PIN3-GFP and PIN4::PIN4-GFP. Data from transcriptional analysis suggests that E. aerogenes VCs trigger hypoxia response, innate immune responses and metabolic processes. In addition, the transcript levels of the genes involved in the synthetic pathways of antimicrobial metabolites camalexin and coumarin are increased after the E. aerogenes VCs exposure. Moreover, we demonstrate that MKK1 serves as a regulator of camalexin biosynthesis gene expression in response to E. aerogenes VCs, while MKK3 is the regulator of coumarin biosynthesis gene expression. Additionally, MKK1 and MKK3 mediate the E. aerogenes VCs-induced callose deposition. Collectively, these studies provide molecular insights into immune responses by plant-deleterious mVCs.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Indóis/metabolismo , Plantas/metabolismo , Cumarínicos/metabolismo , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/metabolismoRESUMO
The scientific community has found immense difficulty to focus on the generation of chiral intermetallics compared to the chiral molecular structure, probably due to the technical difficulty in producing them as no general controlled protocol is available. Herein, using a conventional metal flux technique, we have discovered a new ternary intermetallic Co3Ni3Ga8, substituting Co at the Ni sublattice in a highly symmetric Ni3Ga4 (Ia3Ì d). Co3Ni3Ga8 crystallizes in the I4132 space group, a Sohncke type, and can host the chiral structure. To the best of our knowledge, this is the first report of a ternary intermetallic crystallizing in this space group. The chiral structure of Co3Ni3Ga8 is comprehensively mapped by various techniques such as single-crystal X-ray diffraction (XRD), synchrotron powder XRD, X-ray absorption spectroscopy (XAS), scanning transmission electron microscopy (STEM) and theoretically studied using density functional theory. The discovery of this chiral compound can inspire the researchers to design hidden ternary chiral intermetallics to study the exotic electrical and magnetic properties.
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Tungsten and molybdenum carbides have shown great potential in catalysis and superconductivity. However, the synthesis of ultrathin W/Mo carbides with a controlled dimension and unique structure is still difficult. Here, inspired by the host-guest assembly strategy with single-walled carbon nanotubes (SWCNTs) as a transparent template, we reported the synthesis of ultrathin (0.8-2.0 nm) W2C and Mo2C nanowires confined in SWCNTs deriving from the encapsulated W/Mo polyoxometalate clusters. The atom-resolved electron microscope combined with spectroscopy and theoretical calculations revealed that the strong interaction between the highly carbophilic W/Mo and SWCNT resulted in the anisotropic growth of carbide nanowires along a specific crystal direction, accompanied by lattice strain and electron donation to the SWCNTs. The SWCNT template endowed carbides with resistance to H2O corrosion. Different from normal modification on the outer surface of SWCNTs, such M2C@SWCNTs (M = W, Mo) provided a delocalized and electron-enriched SWCNT surface to uniformly construct the negatively charged Pd catalyst, which was demonstrated to inhibit the formation of active PdHx hydride and thus achieve highly selective semihydrogenation of a series of alkynes. This work could provide a nondestructive way to design the electron-delocalized SWCNT surface and expand the methodology in synthesizing unusual 1D ultrathin carbophilic-metal nanowires (e.g., TaC, NbC, ß-W) with precise control of the anisotropy in SWCNT arrays.
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In the field of supramolecular chemistry, host-guest systems have been extensively explored to encapsulate a wide range of substrates, owing to emerging functionalities in nanoconfined space that cannot be achieved in dilute solutions. However, host-guest chemistry is still limited to encapsulation of small guests. Herein, we construct a water-soluble metallo-supramolecular hexagonal prism with a large hydrophobic cavity by anchoring multiple polyethylene glycol chains onto the building blocks. Then, assembled prisms are able to encapsulate quantum dots (QDs) with diameters of less than 5.0 nm. Furthermore, we find that the supramolecular cage around each QD strongly modifies the photophysics of the QD by universally increasing the rates of QD relaxation processes via ultrafast electron and vibrational energy transfer. Taken together, these efforts expand the scope of substrates in host-guest systems and provide a new approach to tune the optical properties of QDs.
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Covalent organic frameworks (COFs) have emerged as a promising class of crystalline porous materials for cancer phototherapy, due to their exceptional characteristics, including light absorption, biocompatibility, and photostability. However, the aggregation-caused quenching effect and apoptosis resistance often limit their therapeutic efficacy. Herein, we demonstrated for the first time that linking luminogens with aggregation-induced emission effect (AIEgens) into COF networks via vinyl linkages was an effective strategy to construct nonmetallic pyroptosis inducers for boosting antitumor immunity. Mechanistic investigations revealed that the formation of the vinyl linkage in the AIE COF endowed it with not only high brightness but also strong light absorption ability, long lifetime, and high quantum yield to favor the generation of reactive oxygen species for eliciting pyroptosis. In addition, the synergized system of the AIE COF and αPD-1 not only effectively eradicated primary and distant tumors but also inhibited tumor recurrence and metastasis in a bilateral 4T1 tumor model.
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Estruturas Metalorgânicas , Fotoquimioterapia , Piroptose , Apoptose , Carbono , Cloreto de PolivinilaRESUMO
BACKGROUND: While epidemiological studies have established a firm link between circadian disruption and tumorigenesis, the role and mechanism are not fully understood, complicating the design of therapeutic targets related to circadian rhythms (CR). Here, we aimed to explore the intertumoral heterogeneity of CR and elucidate its impact on the tumor microenvironment (TME), drug sensitivity, and immunotherapy. METHODS: Based on unsupervised clustering of 28 CR genes, two distinct CR subtypes (cluster-A and cluster-B) were identified in the TCGA cohort. We further constructed a circadian rhythm signature (CRS) based on the CR genes primarily responsible for clustering to quantify CR activity and to distinguish CR subtypes of individual patients from external datasets. CR subtypes were evaluated by TME characteristics, functional annotation, clinical features, and therapeutic response. RESULTS: The cluster-B (low-CRS) group was characterized by highly enriched immune-related pathways, high immune cell infiltration, and high anti-tumor immunity, while the cluster-A (high-CRS) group was associated with immunosuppression, synaptic transmission pathways, EMT activation, poor prognosis, and drug resistance. Immunohistochemistry (IHC) results demonstrated that high CD8+ T cell infiltration was associated with low-CR-protein expression. Importantly, patients with low CRS were more likely to benefit from immune checkpoint blockade (ICB) treatment, possibly due to their higher tumor mutation burden (TMB), increased immune checkpoint expression, and higher proportion of "hot" immunophenotype. CONCLUSION: In a nutshell, the cross talk in CR could reflect the TME immunoreactivity in breast cancer. Besides providing the first comprehensive pathway-level analysis of CR in breast cancer, this work highlights the potential clinical utility of CR for immunotherapy.
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Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/terapia , Imunoterapia , Terapia de Imunossupressão , Linfócitos T CD8-Positivos , Carcinogênese , Microambiente Tumoral , PrognósticoRESUMO
In this paper, we propose a functional partially linear regression model with latent group structures to accommodate the heterogeneous relationship between a scalar response and functional covariates. The proposed model is motivated by a salinity tolerance study of barley families, whose main objective is to detect salinity tolerant barley plants. Our model is flexible, allowing for heterogeneous functional coefficients while being efficient by pooling information within a group for estimation. We develop an algorithm in the spirit of the K-means clustering to identify latent groups of the subjects under study. We establish the consistency of the proposed estimator, derive the convergence rate and the asymptotic distribution, and develop inference procedures. We show by simulation studies that the proposed method has higher accuracy for recovering latent groups and for estimating the functional coefficients than existing methods. The analysis of the barley data shows that the proposed method can help identify groups of barley families with different salinity tolerant abilities.
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Algoritmos , Humanos , Modelos Lineares , Simulação por ComputadorRESUMO
To explore the microbial community structure and ecological function of mulberry and their potential relationship with the resistance of mulberry, the community structure and function of endophytic fungi in 18 mulberry cultivars were analyzed and predicted by using high-throughput sequencing technology and the FUNGuild database. A total of 352 operational taxonomic units of fungi were observed at a 97% similarity level, representing six phyla of fungi, Fungi_unclassified, Ascomycota, Basidiomycota, Zygomycota, Rozellomycota, and Chytridiomycota. Fungi_unclassified was dominant, and Ascomycota was relatively dominant in all cultivars. At the genus level, Ascomycota_unclassified was dominant, and Ampelomyces was relatively dominant, with a richness in TAIWANCHANGGUOSANG 16.47-8975.69 times that in the other cultivars. Classified Ascomycota_unclassified was 4.75-296.65 times more common in NANYUANSIJI than in the other cultivars. Based on the FUNGuild analysis method, we successfully annotated six nutrient types, namely, pathotroph, pathotroph-saprotroph, pathotroph-saprotroph-symbiotroph, saprotroph, saprotroph-symbiotroph, and symbiotroph, among which saprophytic-symbiotic accounted for the largest proportion and was absolutely dominant in TWC. This research suggests that community composition differs among cultivars and that the diversity and richness of endophytic fungi in resistant cultivars are higher than those in susceptible cultivars. The ecological functions of cultivars with different resistances are quite different.
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Endófitos , Morus , Endófitos/genética , Frutas , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
Peoniflorin-6'-O-benzene sulfonate (CP-25) inhibited the activity of GRK2 to exert anti-inflammatory and immunomodulatory effects. This study aimed to investigate the effect of CP-25 the intestinal epithelial barrier and the mechanism. CaCO-2 cell monolayer and dextran sulfate salt (DSS)-induced colitis mouse model was used to evaluate intestinal epithelial barrier function in vitro and in vivo, respectively. Results showed that CP-25 prevented dysfunction of the intestinal epithelial barrier and inhibited NF-κB p65 activation in TNF-α-induced CaCO-2 cells. The colon structure destroyed in DSS-induced colitis mice was improved by CP-25. CP-25 has a role in inhibition membrane translocation of GRK2-ß-arrestin 2 complex, stabilization of the binding of GRK2 and ß-arrestin 2 to ERK1/2 in cytoplasm. Subsequently down-regulated the nuclear transcription and transactivation of NF-κB p65 via inhibiting its phosphorylation of Ser536, and Ser276, respectively and restored the epithelial barrier function. In conclusion, CP-25 inhibited ERK1/2-NF-κB activation and thereby protected the intestinal epithelial barrier, which was associated with restoring the inhibition of GRK2 and ß-arrestin 2 on ERK1/2.
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Colite , NF-kappa B , Humanos , Camundongos , Animais , NF-kappa B/metabolismo , beta-Arrestina 2/metabolismo , beta-Arrestina 2/farmacologia , Células CACO-2 , Sistema de Sinalização das MAP Quinases , Modelos Animais de Doenças , Mucosa Intestinal , Sulfato de Dextrana , Camundongos Endogâmicos C57BLRESUMO
Chaste-tree (Vitex agnus-castus Linn.) is a perennial ornamental shrub that is native to Europe, which has been widely distributed in China. Since 2021, a serious leaf spot on chaste-tree leaves was observed in Nanjing Botanical Garden, Jiangsu Province, China (31°14'6â³N, 118°22'12â³E). The disease incidence on the leaves ranged from 20 to 40%. The disease symptom initially appeared as irregular small gray spots on leaves that gradually coalesced into larger lesions with diseased leaves turning black and withering. From August of 2021 to 2022, small pieces of leaf tissues (5×5mm) from the necrotic borders of five typical symptomatic infected leaves were collected and surface sterilized (with 75% ethanol), then incubated in darkness at 25°C for 7 days. A total of fifteen isolates were obtained by monosporic isolation (isolation frequency of 76%). The fungal colonies were initially grayish-white and turned into dark gray with abundant cotton-like aerial hyphae. Microscopic observations revealed light-brown conidia that were obclavate or obpyriform (inversely pear-shaped) with length between 10 and 20 µm (mean 13.3 ± 2.4 µm) and widths between 5 and 10 µm (mean 7.8 ± 1.2 µm), 2 to 4 transverse septa and 0 to 2 longitudinal septa per conidium (n=30) were observed. The fungus was identified as Alternaria alternata based on the colony characteristics (Simmons 2007) and the representative isolate Aa1 was used for further studies. To further identify Aa1, the region of internal transcribed spacer (ITS) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), translation elongation factor 1-alpha (EF-1a) and RNA polymerase second largest subunit (RPB2) genes were amplified from genomic DNA and sequenced with the primer pairs ITS1/ITS4 (Jayawardena et al. 2019), EF-728F/EF-986R (Carbone and Kohn 1999), Gpd1/Gpd2 (Berbee et al. 1999) and RPB2-5F/RPB2-7cR (Liu et al. 1999) respectively. Sequences were deposited into GenBank (Accession No. OQ626644 and OQ630494-OQ630496), which showed 99.2 to 100% sequence homology with those A. alternata strains in GeneBank (ITS, MN394880; GAPDH, MN410920; EF-1a, MN410916; RPB2, MN410918). The multigenes phylogenetic analysis revealed that isolate Aa1 and Alternaria alternata TCS3002 + CBS 916.96 clustered within the same clade with 99% bootstrap support. To test pathogenicity, conidial suspension (1×106 spores/ml) of Aa1 was sprayed uniformly across the leaves of three 1-year-old healthy chaste-tree seedlings; sterilized distilled water sprayed on other trees were used as negative control and the experiment was repeated three times. All inoculated plants were kept in same condition (25°C, under a 16 h/8 h photoperiod and 70% relative humidity). One week later, black/gray spots were observed on the leaves of inoculated plants, similar to the symptoms that were observed on the original diseased plants, while controls remained asymptomatic. Cultures were re-isolated from the infected leaves and were again identified as Aa1 by both morphological characteristics and DNA sequence analysis. The pathogen reported here has a broad host range, and has also been reported on Magnolia grandiflora L. (Liu et al. 2019), Kalanchoe pinnata (Sanahuja et al. 2018) and Kadsura coccinea (Zhang et al. 2020) to cause leaf spot. To our knowledge, this is the first report of A. alternata causing leaf spot disease on chaste-tree and provides an important reference for further biology and epidemiology research.
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In the conservation of livestock and poultry resources, population genetic diversity and genetic structure of the conservation population are important factors affecting the effectiveness of conservation. In this study, whole-genome resequencing technology was used to detect genomic variation in 100 Qinchuan cattle (30 bulls and 70 cows). By analyzing population genetic diversity, runs of homozygosity (ROH) distribution features, kinship relationships, and family structure, the conservation effectiveness of Qinchuan cattle was comprehensively evaluated. The results showed that a total of 20,968,017 high-quality SNPs were detected in 100 Qinchuan cattle, the average minimum allele frequency was 0.191±0.124, the average polymorphic information content was 0.279±0.131, and the average observed heterozygosity was 0.275±0.131, the average expected heterozygosity is 0.279±0.131, indicating that the genetic diversity of the Qinchuan cattle conservation population is relatively rich. The average identity by state (IBS) distance of the Qinchuan conservation population was 0.243±0.020, with a value of 0.242±0.021 for the bulls. The results of the kinship G-matrix were consistent with the results of the IBS distance matrix, both showing that some individuals in the conservation population had close kinship. A total of 8258 genomic ROH were detected in 100 Qinchuan cattle, with a total length of 9.64 GB. The average length of ROH fragments was 1.167±1.203 Mb, 69.35% of the ROH were short ROH with a length of 0.5~1 Mb, and the average total length of ROH per individual was 96.40 Mb. The average inbreeding coefficient based on ROH was 0.039±0.039, with a value of 0.044±0.035 for the bulls, indicating that some bulls had a certain degree of inbreeding accumulation. The results of the phylogenetic tree combined with kinship analysis showed that the individuals in the Qinchuan cattle conservation population could be divided into eight families, including seven families with bulls and one family without bulls. This study demonstrated that the genetic diversity of the Qinchuan conservation population is relatively rich, with no significant inbreeding accumulation, but there is a risk of inbreeding among some individuals. Therefore, it is necessary to strengthen selection and mating to ensure the sustainable development of Qinchuan cattle resources.
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Bovinos , Endogamia , Animais , Bovinos/genética , Feminino , Masculino , Genoma/genética , Genótipo , Homozigoto , Filogenia , Polimorfismo de Nucleotídeo ÚnicoRESUMO
The perceived position of a moving object in vision entails an accumulation of neural signals over space and time. Due to neural signal transmission delays, the visual system cannot acquire immediate information about the moving object's position. Although physiological and psychophysical studies on the flash-lag effect (FLE), a moving object is perceived ahead of a flash even when they are aligned at the same location, have shown that the visual system develops the mechanisms of predicting the object's location to compensate for the neural delays, the neural mechanisms of motion-induced location prediction are not still understood well. Here, we investigated the role of neural activity changes in areas MT+ (specialized for motion processing) and the potential contralateral processing preference of MT+ in modulating the FLE. Using transcranial direct current stimulations (tDCS) over the left and right MT+ between pre- and posttests of the FLE in different motion directions, we measured the effects of tDCS on the FLE. The results found that anodal and cathodal tDCS enhanced and reduced the FLE with the moving object heading to but not deviating from the side of the brain stimulated, respectively, compared with sham tDCS. These findings suggest a causal role of area MT+ in motion-induced location prediction, which may involve the integration of position information.NEW & NOTEWORTHY Perceived positions of moving objects are related to neural activities in areas MT+. We demonstrate that tDCS over areas MT+ can modulate the FLE, and further anodal and cathodal tDCS facilitated and inhibited the FLE with a moving object heading to but not deviating from the side of the brain stimulated, respectively. These findings suggest a causal role of area MT+ in motion-induced location prediction and contribute to understanding the neural mechanism of the FLE.
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Percepção de Movimento , Estimulação Transcraniana por Corrente Contínua , Encéfalo , Eletrodos , Inibição Psicológica , Percepção de Movimento/fisiologiaRESUMO
Perceptual learning is commonly assumed to enhance perception through continuous attended sensory input. However, learning is generalizable to performance in untrained stimuli and tasks. Although previous studies have observed a possible generalization effect across tasks as a result of working memory (WM) training, comparisons of the contributions of WM training and continuous attended sensory input to perceptual learning generalization are still rare. Therefore, we compared which factors contributed most to perceptual generalization and investigated which skills acquired during WM training led to tactile generalization across tasks. Here, a Braille-like dot pattern matching n-back WM task was used as the WM training task, with four workload levels (0, 1, 2, and 3-back levels). A tactile angle discrimination (TAD) task was used as a pre- and posttest to assess improvements in tactile perception. Between tests, four subject groups were randomly assigned to four different workload n-back tasks to consecutively complete three sessions of training. The results showed that tactile n-back WM training could enhance TAD performance, with the 3-back training group having the highest TAD threshold improvement rate. Furthermore, the rate of WM capacity improvement on the 3-back level across training sessions was correlated with the rate of TAD threshold improvement. These findings suggest that continuous attended sensory input and enhanced WM capacity can lead to improvements in TAD ability, and that greater improvements in WM capacity can predict greater improvements in TAD performance.NEW & NOTEWORTHY Perceptual learning is not always specific to the trained task and stimuli. We demonstrate that both continuous attended sensory input and improved WM capacity can be used to enhance tactile angle discrimination (TAD) ability. Moreover, WM capacity improvement is important in generalizing the training effect to the TAD ability. These findings contribute to understanding the mechanism of perceptual learning generalization across tasks.