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1.
Nat Commun ; 15(1): 8013, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39271661

RESUMEN

Enhancing drought tolerance in crops and understanding the underlying mechanisms have been subject of intense research. The precise function and molecular mechanisms of B-box zinc finger proteins (BBX) remain elusive. Here, we report a natural allele of BBX18 (BBX18TT) that encodes a C-terminal truncated protein. While most wild tomato germplasms contain the BBX18CC allele and show more drought tolerant, modern cultivated tomatoes mostly carry BBX18TT allele and are more drought sensitive. Knockout of BBX18 leads to improved drought tolerance in transgenic plants of cultivated tomato. Ascorbate peroxidase 1 (APX1) is identified as a BBX18-interacting protein that acts as a positive regulator of drought resistance in tomato. Chromatin immunoprecipitation sequencing analyses reveal that BBX18 binds to a unique cis-acting element of the APX1 promoter and represses its gene expression. This study provides insights into the molecular mechanism underlying drought resistance mediated by the BBX18-APX1 module in plants.


Asunto(s)
Sequías , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Plantas Modificadas Genéticamente , Solanum lycopersicum , Factores de Transcripción , Dedos de Zinc , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Dedos de Zinc/genética , Regiones Promotoras Genéticas/genética , Ascorbato Peroxidasas/metabolismo , Ascorbato Peroxidasas/genética , Alelos
2.
Front Plant Sci ; 15: 1459013, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39290736

RESUMEN

Introduction: Fruit color significantly influences the quality of horticultural crops, which affects phytochemical diversity and consumer preferences. Despite its importance, the genetic basis of the white-colored fruit in tomatoes remains poorly understood. Methods: In this study, we demonstrate that white-fleshed tomato varieties accumulate fewer carotenoids than yellow-fleshed varieties. We developed various segregating populations by hybridizing red, yellow, and white fruit tomato cultivars. Results: Genetic analysis revealed that the white fruit color trait is controlled by a single gene that dominates both red and yellow fruits. Bulk segregant RNA sequencing provided a preliminary map of a 3.17 Mb region on chromosome 3 associated with the white color trait. Based on kompetitive allele-specific PCR (KASP) markers, we narrowed the candidate gene region to 819 kb. Within this region, we identified a 4906-bp sequence absence variation near Phytoene Synthase 1 (SlPSY1) specific to white-colored tomatoes. Genotyping of the progeny and natural populations using a single nucleotide polymorphism adjacent to this absence of variation confirmed its key role in white fruit formation. Discussion: Collectively, our findings provide insights into white fruit trait formation in tomatoes, enabling tomato breeders to precisely introduce white fruit traits for commercial exploitation.

3.
Cell Host Microbe ; 32(9): 1566-1578.e5, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39106871

RESUMEN

Viral suppressor RNA silencing (VSR) is essential for successful infection. Nucleotide-binding and leucine-rich repeat (NLR)-based and autophagy-mediated immune responses have been reported to target VSR as counter-defense strategies. Here, we report a protein arginine methyltransferase 6 (PRMT6)-mediated defense mechanism targeting VSR. The knockout and overexpression of PRMT6 in tomato plants lead to enhanced and reduced disease symptoms, respectively, during tomato bush stunt virus (TBSV) infection. PRMT6 interacts with and inhibits the VSR function of TBSV P19 by methylating its key arginine residues R43 and R115, thereby reducing its dimerization and small RNA-binding activities. Analysis of the natural tomato population reveals that two major alleles associated with high and low levels of PRMT6 expression are significantly associated with high and low levels of viral resistance, respectively. Our study establishes PRMT6-mediated arginine methylation of VSR as a mechanism of plant immunity against viruses.


Asunto(s)
Enfermedades de las Plantas , Inmunidad de la Planta , Proteína-Arginina N-Metiltransferasas , Solanum lycopersicum , Proteína-Arginina N-Metiltransferasas/metabolismo , Proteína-Arginina N-Metiltransferasas/genética , Enfermedades de las Plantas/virología , Enfermedades de las Plantas/inmunología , Solanum lycopersicum/virología , Solanum lycopersicum/inmunología , Solanum lycopersicum/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/inmunología , Arginina/metabolismo , Metilación , Interferencia de ARN , Proteínas Virales/metabolismo , Proteínas Virales/genética , Interacciones Huésped-Patógeno/inmunología , Regulación de la Expresión Génica de las Plantas
4.
Front Plant Sci ; 15: 1386824, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39011307

RESUMEN

The occurring temperature increase in crop production areas worldwide is generating conditions of heat stress that negatively affect crop productivity. Tomato (Solanum lycopersicum), a major vegetable crop, is highly susceptible to elevated temperatures. Under such conditions, fruit set is dramatically reduced, leading to significant yield losses. Solanum pimpinellifolium, a wild species closely related to the cultivated tomato, was shown to have beneficial attributes under various abiotic stress growth conditions. We have utilized a new population of backcross inbred lines originated from a cross between S. pimpinellifolium and S. lycopersicum, in order to evaluate its potential as a new genetic resource for improvement of reproductive performance of cultivated tomato under heat stress conditions. This population was screened for various heat stress-related traits, under controlled heat stress and non-stress conditions. Our results show that significant variation exists for all the heat stress related traits that were examined and point at individual lines with better reproductive performance under heat stress conditions that share a common introgression from the wild S. pimpinellifolium parent, suggesting several candidate genes as potential drivers of thermotolerance. Thus, our results place this population as a valuable new resource for the discovery of heat stress related genetic loci for the future development of heat stress tolerant tomato cultivars.

5.
Small ; : e2403903, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953301

RESUMEN

Asymmetric electronic environments based on microscopic-scale perspective have injected infinite vitality in understanding the intrinsic mechanism of polarization loss for electromagnetic (EM) wave absorption, but still exists a significant challenge. Herein, Zn single-atoms (SAs), structural defects, and Co nanoclusters are simultaneously implanted into bimetallic metal-organic framework derivatives via the two-step dual coordination-pyrolysis process. Theoretical simulations and experimental results reveal that the electronic coupling interactions between Zn SAs and structural defects delocalize the symmetric electronic environments and generate additional dipole polarization without sacrificing conduction loss owing to the compensation of carbon nanotubes. Moreover, Co nanoclusters with large nanocurvatures induce a strong interfacial electric field, activate the superiority of heterointerfaces and promote interfacial polarization. Benefiting from the aforementioned merits, the resultant derivatives deliver an optimal reflection loss of -58.9 dB and the effective absorption bandwidth is 5.2 GHz. These findings provide an innovative insight into clarifying the microscopic loss mechanism from the asymmetric electron environments viewpoint and inspire the generalized electronic modulation engineering in optimizing EM wave absorption.

6.
Plant Physiol Biochem ; 214: 108968, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39074436

RESUMEN

Cadmium (Cd) is a hazardous heavy metal known for its detrimental effects on plants, human health, and the environment. This review article delves into the dynamics of Cd uptake, long-distance transport, and its impact on plant performance, with a specific focus on tomato plants. The process of Cd uptake by roots and its subsequent long-distance transport in the xylem and phloem are explored to understand how Cd influences plants operation. The toxic effects of Cd on tomato plants are discussed, highlighting on the challenges it poses to plant growth and development. Furthermore, the review investigates various Cd tolerance mechanisms in plants, including avoidance or exclusion by the root cell wall, root-to-shoot translocation, detoxification pathways, and antioxidative defence systems against Cd-induced stress. In addition, the transcriptomic analyses of tomato plants under Cd stress provide insights into the molecular responses and adaptations of plants to Cd toxicity. Overall, this comprehensive review enhances our understanding of Cd-plant interactions and reveal promising genes for tomato genetic improvement to increase its tolerance to cadmium.


Asunto(s)
Cadmio , Solanum lycopersicum , Solanum lycopersicum/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/efectos de los fármacos , Cadmio/metabolismo , Cadmio/toxicidad , Raíces de Plantas/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/efectos de los fármacos , Transporte Biológico , Inactivación Metabólica/genética
7.
Brief Bioinform ; 25(3)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38701418

RESUMEN

Coverage quantification is required in many sequencing datasets within the field of genomics research. However, most existing tools fail to provide comprehensive statistical results and exhibit limited performance gains from multithreading. Here, we present PanDepth, an ultra-fast and efficient tool for calculating coverage and depth from sequencing alignments. PanDepth outperforms other tools in computation time and memory efficiency for both BAM and CRAM-format alignment files from sequencing data, regardless of read length. It employs chromosome parallel computation and optimized data structures, resulting in ultrafast computation speeds and memory efficiency. It accepts sorted or unsorted BAM and CRAM-format alignment files as well as GTF, GFF and BED-formatted interval files or a specific window size. When provided with a reference genome sequence and the option to enable GC content calculation, PanDepth includes GC content statistics, enhancing the accuracy and reliability of copy number variation analysis. Overall, PanDepth is a powerful tool that accelerates scientific discovery in genomics research.


Asunto(s)
Genómica , Programas Informáticos , Genómica/métodos , Humanos , Análisis de Secuencia de ADN/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Composición de Base , Variaciones en el Número de Copia de ADN , Biología Computacional/métodos , Algoritmos , Alineación de Secuencia/métodos
8.
Nanomicro Lett ; 16(1): 176, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38647737

RESUMEN

The utilization of electromagnetic waves is rapidly advancing into the millimeter-wave frequency range, posing increasingly severe challenges in terms of electromagnetic pollution prevention and radar stealth. However, existing millimeter-wave absorbers are still inadequate in addressing these issues due to their monotonous magnetic resonance pattern. In this work, rare-earth La3+ and non-magnetic Zr4+ ions are simultaneously incorporated into M-type barium ferrite (BaM) to intentionally manipulate the multi-magnetic resonance behavior. By leveraging the contrary impact of La3+ and Zr4+ ions on magnetocrystalline anisotropy field, the restrictive relationship between intensity and frequency of the multi-magnetic resonance is successfully eliminated. The magnetic resonance peak-differentiating and imitating results confirm that significant multi-magnetic resonance phenomenon emerges around 35 GHz due to the reinforced exchange coupling effect between Fe3+ and Fe2+ ions. Additionally, Mössbauer spectra analysis, first-principle calculations, and least square fitting collectively identify that additional La3+ doping leads to a profound rearrangement of Zr4+ occupation and thus makes the portion of polarization/conduction loss increase gradually. As a consequence, the La3+-Zr4+ co-doped BaM achieves an ultra-broad bandwidth of 12.5 + GHz covering from 27.5 to 40 + GHz, which holds remarkable potential for millimeter-wave absorbers around the atmospheric window of 35 GHz.

9.
Molecules ; 29(6)2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38542966

RESUMEN

Cytotoxic T-lymphocyte antigen 4 (CTLA-4) is a pivotal immune checkpoint receptor, playing a crucial role in modulating T-cell activation. In this study, we delved into the underlying mechanism by which a common mutation, G199R, in the cytoplasmic domain of CTLA-4 impacts its inhibitory function. Utilizing nuclear magnetic resonance (NMR) spectroscopy and biochemical techniques, we mapped the conformational changes induced by this mutation and investigated its role in CTLA-4 activity. Our findings reveal that this mutation leads to a distinct conformational alteration, enhancing protein-membrane interactions. Moreover, functional assays demonstrated an improved capacity of the G199R mutant to downregulate T-cell activation, underscoring its potential role in immune-related disorders. These results not only enhance our understanding of CTLA-4 regulatory mechanisms but also provide insights for targeted therapeutic strategies addressing immune dysregulation linked to CTLA-4 mutations.


Asunto(s)
Comunicación Celular , Activación de Linfocitos , Antígeno CTLA-4/genética , Mutación , Activación de Linfocitos/genética
10.
Food Chem ; 447: 138946, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-38498952

RESUMEN

Rice bran, recognized for its rich lipids and health-beneficial bioactive compounds, holds considerable promise in applications such as rice bran oil production. However, its susceptibility to lipid hydrolysis and oxidation during storage presents a significant challenge. In response, we conducted an in-depth metabolic profiling of rice bran over a storage period of 14 days. We focused on the identification of bioactive compounds and functional lipid species (25 acylglycerols and 53 phospholipids), closely tracking their dynamic changes over time. Our findings revealed significant reductions in these lipid molecular species, highlighting the impact of rancidity processes. Furthermore, we identified 19 characteristic lipid markers and elucidated that phospholipid and glycerolipid metabolism were key metabolic pathways involved. By shedding light on the mechanisms driving lipid degradation in stored rice bran, our study significantly advanced the understanding of lipid stability. These information provided valuable insights for countering rancidity and optimizing rice bran preservation strategies.


Asunto(s)
Lipidómica , Oryza , Hidrólisis , Oxidación-Reducción , Fosfolípidos , Lipólisis , Aceite de Salvado de Arroz
11.
J Oleo Sci ; 73(2): 135-145, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38311404

RESUMEN

In the pursuit of reducing oil separation in peanut butter, oleogels synthesized from diacylglycerol (DAG)-rich peanut oils, using glycerol monostearate (GMS) as the gelator, were examined as alternative stabilizers. In comparison to triacylglycerol (TAG)-rich peanut oils, the DAG oil-based oleogels exhibited better oil-binding capacities across increasing GMS concentrations. Intriguingly, thermal and rheological assessments pointed to a weaker network structure in DAG oil oleogels, as evidenced by their lower crystallization temperatures and reduced viscoelastic parameters (G' and G''). Insight from infrared spectroscopy revealed that this could stem from heightened intermolecular hydrogen bonding between the DAG oil and the gelator. When applied to peanut butter, DAG oil oleogels demonstrated efficacy in minimizing oil separation. Extended storage trials affirmed the long-term stability of peanut butter formulations incorporating these oleogels. Furthermore, sensory evaluations by panelists underscored favorable impressions, suggesting potential consumer acceptance. Overall, this study illuminates the promising role of DAG oleogels as effective, alternative stabilizers in peanut butter formulations.


Asunto(s)
Arachis , Diglicéridos , Aceites , Compuestos Orgánicos/química
12.
J Mol Biol ; 436(8): 168500, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38401626

RESUMEN

Programmed cell death 1 ligand 2 (PD-L2), a member of the B7 immune checkpoint protein family, emerges as a crucial player in immune modulation. Despite its functional overlap with programmed cell death 1 ligand 1 (PD-L1) in binding to the programmed cell death protein 1 (PD-1) on T cells, PD-L2 exhibits a divergent expression pattern and a higher affinity for PD-1. However, the regulatory mechanisms of PD-L2 remain under-explored. Here, our investigations illustrate the pivotal role of cholesterol in modulating PD-L2 stability. Using advanced nuclear magnetic resonance (NMR) and biochemical analyses, we demonstrate a direct and specific binding between cholesterol and PD-L2, mediated by an F-xxx-V-xx-LR motif in its transmembrane domain, distinct from that in PD-L1. This interaction stabilizes PD-L2 and prevents its downstream degradation. Disruption of this binding motif compromises PD-L2's cellular stability, underscoring its potential significance in cancer biology. These findings not only deepen our understanding of PD-L2 regulation in the context of tumors, but also open avenues for potential therapeutic interventions.


Asunto(s)
Colesterol , Proteína 2 Ligando de Muerte Celular Programada 1 , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Receptor de Muerte Celular Programada 1 , Dominios Proteicos , Linfocitos T/metabolismo , Células HEK293 , Humanos , Estabilidad Proteica , Proteína 2 Ligando de Muerte Celular Programada 1/química , Proteína 2 Ligando de Muerte Celular Programada 1/metabolismo , Colesterol/química , Colesterol/metabolismo
13.
Plant Physiol ; 194(2): 1075-1090, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-37935624

RESUMEN

Tomato (Solanum lycopersicum) is a cold-sensitive crop but frequently experiences low-temperature stimuli. However, tomato responses to cold stress are still poorly understood. Our previous studies have shown that using wild tomato (Solanum habrochaites) as rootstock can significantly enhance the cold resistance of grafted seedlings, in which a high concentration of jasmonic acids (JAs) in scions exerts an important role, but the mechanism of JA accumulation remains unclear. Herein, we discovered that tomato SlWRKY50, a Group II WRKY transcription factor that is cold inducible, responds to cold stimuli and plays a key role in JA biosynthesis. SlWRKY50 directly bound to the promoter of tomato allene oxide synthase gene (SlAOS), and overexpressing SlWRKY50 improved tomato chilling resistance, which led to higher levels of Fv/Fm, antioxidative enzymes, SlAOS expression, and JA accumulation. SlWRKY50-silenced plants, however, exhibited an opposite trend. Moreover, diethyldithiocarbamate acid (a JA biosynthesis inhibitor) foliar treatment drastically reduced the cold tolerance of SlWRKY50-overexpression plants to wild-type levels. Importantly, SlMYC2, the key regulator of the JA signaling pathway, can control SlWRKY50 expression. Overall, our research indicates that SlWRKY50 promotes cold tolerance by controlling JA biosynthesis and that JA signaling mediates SlWRKY50 expression via transcriptional activation by SlMYC2. Thus, this contributes to the genetic knowledge necessary for developing cold-resistant tomato varieties.


Asunto(s)
Solanum lycopersicum , Solanum , Solanum lycopersicum/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Regulación de la Expresión Génica de las Plantas , Oxilipinas/metabolismo , Solanum/fisiología , Ciclopentanos/metabolismo , Transducción de Señal/genética , Frío
15.
Eur J Ophthalmol ; 34(2): 384-393, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37438954

RESUMEN

PURPOSE: To evaluate the corneal biological parameters stability between the different corneal residual bed thickness (RBT) after Small Incision Lenticule Extraction (SMILE). METHODS: In this prospective clinical trial, 127 eyes of 64 patients underwent SMILE. According to the corneal RBT, the patients were divided into the 250-270 µm, 270-290 µm and 290-310 µm groups. Corvis ST (Oculus Optikgeräte GmbH, Wetzlar, Germany) and Scheimpflug camera (Pentacam; Oculus Optikgeräte GmbH, Wetzlar, Germany) measurements were performed preoperatively, 1 day, 1week, 1month and 3 months after surgery. RESULTS: The keratometer values among the three groups were no significant differences in postoperative periods (each P > 0.05), except the corneal thickness values (each P < 0.05). In the 250-270 µm and 270-290 µm groups, the keratometer and corneal thickness values were decreased at postoperative 1 week and increased at 1 and 3 months. The 290-310 µm group significantly higher posterior maximum elevation (PME) than the 250-270 µm group at 1 and 3 months (P = 0.022, 0.022, respectively), and higher preoperative thinnest point (PTE) at 1 week and 1 month (P = 0.013, 0.035, respectively). The PME of the 290-310 µm group was higher than the 270-290 µm group at 3 months (P = 0.045), and higher PTE at 1 week and 3 months (P = 0.022, 0.02, respectively). In all three groups, the maximal deformation amplitude (DA) was significantly higher at 1 and 3 months compared to postoperative 1 day and 1 week, and the IOP was decreased at 1 month then recovered at 3 months (each P < 0.05).The DA of the 250-270 µm group was significantly higher than the 290-310 µm group at postoperative 1 week, 1 and 3 months (P = 0.001, 0.01, 0.02, respectively). The change of the posterior corneal elevation and biomechanical parameters values were no significant differences among the three groups in postoperative periods (each P > 0.05). CONCLUSIONS: The range of 250-310 µm RBT was safe and stable at the early postoperative of SMILE. The RBT may be positively correlated with the posterior corneal elevation.


Asunto(s)
Cirugía Laser de Córnea , Miopía , Humanos , Córnea/cirugía , Sustancia Propia/cirugía , Topografía de la Córnea , Miopía/cirugía , Agudeza Visual
16.
Front Plant Sci ; 14: 1282718, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37936934

RESUMEN

Drought is among the most common abiotic constraints of crop growth, development, and productivity. Integrating different omics approaches offers a possibility for deciphering the metabolic pathways and fundamental mechanisms involved in abiotic stress tolerance. Here, we explored the transcriptional and post-transcriptional changes in drought-stressed tomato plants using transcriptomic and proteomic profiles to determine the molecular dynamics of tomato drought stress responses. We identified 22467 genes and 5507 proteins, among which the expression of 3765 genes and 294 proteins was significantly changed under drought stress. Furthermore, the differentially expressed genes (DEGs) and differentially abundant proteins (DAPs) showed a good correlation (0.743). The results indicated that integrating different omics approaches is promising in exploring the multilayered regulatory mechanisms of plant drought resistance. Gene ontology (GO) and pathway analysis identified several GO terms and pathways related to stress resistance, including response to stress, abiotic stimulus, and oxidative stress. The plant hormone abscisic acid (ABA) plays pivotal roles in response to drought stress, ABA-response element binding factor (AREB) is a key positive regulator of ABA signaling. Moreover, our analysis indicated that drought stress increased the abscisic acid (ABA) content, which activated AREB1 expression to regulate the expression of TAS14, GSH-Px-1, and Hsp, ultimately improving tomato drought resistance. In addition, the yeast one-hybrid assay demonstrated that the AREB1 could bind the Hsp promoter to activate Hsp expression. Thus, this study involved a full-scale analysis of gene and protein expression in drought-stressed tomato, deepening the understanding of the regulatory mechanisms of the essential drought-tolerance genes in tomato.

17.
Phys Chem Chem Phys ; 25(46): 31628-31635, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37982294

RESUMEN

Two-dimensional (2D) layered transition metal dichalcogenides such as MoS2 have been viewed as the most favorable candidates for replacing noble metals in catalyzing the hydrogen evolution reaction in water splitting owing to their earth abundance, superb chemical stability, and appropriate Gibbs free energy. However, due to its low number of catalytic sites and basal catalytic inertia, the pristine MoS2 displayed intrinsically unsatisfactory HER catalytic activity. Here, the hydrogen evolution catalytic activities of nanostructured MoS2 powder before and after plasma modification with nitrogen doping were experimentally compared, and the influence of treatment parameters on the hydrogen evolution catalytic performance of MoS2 has been studied. The feasibility of regulating hydrogen evolution catalytic activity by nitrogen doping of MoS2 was verified based on density functional theory calculations. Our work demonstrates a more convenient and faster way to develop cheap and efficient MoS2-based catalysts for electrochemical hydrogen evolution reactions. Additionally, theoretical studies reveal that N-doped MoS2 exhibits strong hybridization between Mo-d and N-p states, causing magnetism to evolve, as confirmed by experiments.

18.
J Am Chem Soc ; 145(49): 27010-27021, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-37949810

RESUMEN

Two-dimensional (2D) Pt-group ultrathin nanosheets (NSs) are promising advanced electrocatalysts for energy-related catalytic reactions. However, improving the electrocatalytic activity of 2D Pt-group NSs through the addition of abundant grain boundaries (GBs) and understanding the underlying formation mechanism remain significant challenges. Herein, we report the controllable synthesis of a series of Rh-based nanocrystals (e.g., Rh nanoparticles, Rh NSs, and Rh NSs with GBs) through a CO-mediated kinetic control synthesis route. In light of the 2D NSs' structural advantages and GB modification, the Rh NSs with rich GBs exhibit an enhanced electrocatalytic activity compared to pure Rh NSs and commercial Pt/C toward the hydrogen oxidation reaction (HOR) in alkaline media. Both experimental results and theoretical computations corroborate that the GBs in the Rh NSs have the capacity to ameliorate the adsorption free energy of reaction intermediates during the HOR, thus resulting in outstanding HOR catalytic performance. Our work offers novel perspectives in the realm of developing sophisticated 2D Pt-group metal electrocatalysts with rich GBs for the energy conversion field.

19.
Artículo en Inglés | MEDLINE | ID: mdl-37995171

RESUMEN

Untreated pain in critically ill patients can lead to immunosuppression and increased metabolic activity, with severe clinical consequences such as tachypnea and delirium. Continuous pain assessment is challenging due to nursing shortages and intensive care unit (ICU) workload. Mechanical ventilation equipment obscures the facial features of many patients in the ICU, making previous facial pain detection methods based on full-face images inapplicable. This paper proposes a facial Action Units (AUs) guided pain assessment network for faces under occlusion. The network consists of an AU-guided (AUG) module, a texture feature extraction (TFE) module, and a pain assessment (PA) module. The AUG module automatically detects AUs in the non-occluded areas of the face. In contrast, the TFE module detects the facial landmarks and crops prior knowledge patches, a random exploration patch, and a global feature patch. Then these patches are fed into two convolutional networks to extract texture features. Afterward, the designed AU guidances and texture features are fused in the PA module to assess the pain state. Extensive validation is conducted on a public dataset and two datasets created in this work. The proposed network architecture achieves superior performance in binary classification, four-class classification, and intensity regression tasks. In addition, we have successfully applied the network to actual data collected in the laboratory environment with excellent results.

20.
Cyborg Bionic Syst ; 4: 0042, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37675200

RESUMEN

In the robot-assisted minimally invasive surgery, if a collision occurs, the robot system program could be damaged, and normal tissues could be injured. To avoid collisions during surgery, a 3-dimensional collision avoidance method is proposed in this paper. The proposed method is predicated on the design of 3 strategic vectors: the collision-with-instrument-avoidance (CI) vector, the collision-with-tissues-avoidance (CT) vector, and the constrained-control (CC) vector. The CI vector demarcates 3 specific directions to forestall collision among the surgical instruments. The CT vector, on the other hand, comprises 2 components tailored to prevent inadvertent contact between the robot-controlled instrument and nontarget tissues. Meanwhile, the CC vector is introduced to guide the endpoint of the robot-controlled instrument toward the desired position, ensuring precision in its movements, in alignment with the surgical goals. Simulation results verify the proposed collision avoidance method for robot-assisted minimally invasive surgery. The code and data are available at https://github.com/cynerelee/collision-avoidance.

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