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1.
Materials (Basel) ; 17(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38730766

RESUMO

With the rapid development of high and new technology, rubidium and its compounds show broad application prospect and market demand with their unique characteristics. At present, the production of rubidium metal is mainly prepared by calcium thermal reduction of rubidium chloride. Rubidium metal obtained by reduction requires multi-step vacuum distillation to obtain high-purity rubidium metal. The purity of rubidium metal depends on the purity of the raw material rubidium chloride. Rubidium metal is relatively active and is easy to oxidize and explode in air. Therefore, a method combining vacuum decomposition and vacuum distillation to reduce impurity elements in rubidium chloride from raw materials is proposed in this paper. The experimental results show that under the conditions of pressure of 5-10 Pa, distillation temperature of 823 K and vacuum distillation time of 60 min, the contents of Si and Zn impurities are reduced from 1206 mg/kg and 310 mg/kg to less than 0.1 mg/kg, and the removal rates are 99.99% and 99.97%, respectively. Rubidium chloride has almost no loss, and through one-step vacuum distillation, the impurity elements silicon and zinc can be deeply removed, reducing the flammability and explosiveness, high cost, long process and other problems caused by the subsequent preparation of high-purity rubidium metal.

2.
J Hazard Mater ; 472: 134568, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38749246

RESUMO

Cadmium (Cd) is a heavy metal that significantly impacts human health and the environment. Microorganisms play a crucial role in reducing heavy metal stress in plants; however, the mechanisms by which microorganisms enhance plant tolerance to Cd stress and the interplay between plants and microorganisms under such stress remain unclear. In this study, Oceanobacillus picturae (O. picturae) was isolated for interaction with soybean seedlings under Cd stress. Results indicated that Cd treatment alone markedly inhibited soybean seedling growth. Conversely, inoculation with O. picturae significantly improved growth indices such as plant height, root length, and fresh weight, while also promoting recovery in soil physiological indicators and pH. Metabolomic and transcriptomic analyses identified 157 genes related to aspartic acid, cysteine, and flavonoid biosynthesis pathways. Sixty-three microbial species were significantly associated with metabolites in these pathways, including pathogenic, adversity-resistant, and bioconductive bacteria. This research experimentally demonstrates, for the first time, the growth-promoting effect of the O. picturae strain on soybean seedlings under non-stress conditions. It also highlights its role in enhancing root growth and reducing Cd accumulation in the roots under Cd stress. Additionally, through the utilization of untargeted metabolomics, metagenomics, and transcriptomics for a multi-omics analysis, we investigated the impact of O. picturae on the soil microbiome and its correlation with differential gene expression in plants. This innovative approach unveils the molecular mechanisms underlying O. picturae's promotion of root growth and adaptation to Cd stress.

3.
J Orthop Sci ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38565448

RESUMO

BACKGROUND: This study aimed to determine risk factors for poor in-hospital outcomes in a large cohort of older adult patients with acute non-traffic traumatic spinal cord injury (tSCI). METHODS: This is a population-based, retrospective, observational study. Data of older adults ≥65 years with a primary discharge diagnosis of acute non-traffic tSCI were extracted from the US National Inpatient Sample (NIS) database 2005-2018. Traffic-related tSCI admissions or patients lacking complete data on age, sex and outcomes of interest were excluded. Univariate and multivariate logistic regression analysis was used to determine associations between variables and in-hospital outcomes. RESULTS: Data of 49,449 older patients (representing 246,939 persons in the US) were analyzed. The mean age was 79.9 years. Multivariable analyses revealed that severe International Classification of Disease (ICD)-based injury severity score (ICISS) (adjusted odds ratio [aOR] = 3.14, 95% confidence interval [CI]: 2.77-3.57), quadriplegia (aOR = 2.79, 95%CI: 2.34-3.32), paraplegia (aOR = 2.60, 95%CI:1.89-3.58), cervical injury with vertebral fracture (aOR = 2.19, 95%CI: 1.90-2.52), and severe liver disease (aOR = 2.33, 95%CI: 1.34-4.04) were all strong independent predictors of in-hospital mortality. In addition, malnutrition (aOR = 3.19, 95% CI: 2.93-3.48) was the strongest predictors of prolonged length of stay (LOS). CONCLUSIONS: Several critical factors for in-hospital mortality, unfavorable discharge, and prolonged LOS among US older adults with acute non-traffic tSCI were identified. In addition to the factors associated with initial severity, the presence of severe liver disease and malnutrition emerged as strong predictors of unfavorable outcomes, highlighting the need for special attention for these patient subgroups.

4.
Plants (Basel) ; 13(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38592937

RESUMO

Soybean is the major global source of edible oils and vegetable proteins. Seed size and weight are crucial traits determining the soybean yield. Understanding the molecular regulatory mechanism underlying the seed weight and size is helpful for improving soybean genetic breeding. The molecular regulatory pathways controlling the seed weight and size were investigated in this study. The 100-seed weight, seed length, seed width, and seed weight per plant of a chromosome segment substitution line (CSSL) R217 increased compared with those of its recurrent parent 'Suinong14' (SN14). Transcriptomic and proteomic analyses of R217 and SN14 were performed at the seed developmental stages S15 and S20. In total, 2643 differentially expressed genes (DEGs) and 208 differentially accumulated proteins (DAPs) were detected at S15, and 1943 DEGs and 1248 DAPs were detected at S20. Furthermore, integrated transcriptomic and proteomic analyses revealed that mitogen-activated protein kinase signaling and cell wall biosynthesis and modification were potential pathways associated with seed weight and size control. Finally, 59 candidate genes that might control seed weight and size were identified. Among them, 25 genes were located on the substituted segments of R217. Two critical pathways controlling seed weight were uncovered in our work. These findings provided new insights into the seed weight-related regulatory network in soybean.

5.
BMC Oral Health ; 24(1): 46, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191426

RESUMO

OBJECTIVES: The accurate localization of the foreign bodies (FBs) is essential. This work presents a new noninvasive technique for subcutaneous metallic FBs under a radiographic grid, a system that simplifies the localization of facial FBs removal using a grid with embedded reference points. METHODS: This work designed a retrospective study to evaluate the effect of a radiographic grid on FBs removal surgery. All patients who met the inclusion criteria and attended the Hospital of Stomatology of China Medical University from January 2022 to June 2023 were enrolled and randomly divided into grid and non-grid groups. The assessment of facial swelling, the primary indicator, was conducted on days 2 and 7 post-surgery. The variables were analyzed using the Student t test and a repeated-measures general linear model. RESULTS: The study sample consisted of 20 patients, with 14 males (70%) and 6 females (30%), who had an average age of 30.30 ± 5.38. The average time of operation was 1.85 ± 0.66 h (range 0.7 to 3.2). In the present cases in this report, of the 20 patients' FBs, 14 were metal, 5 were glass, and 1 was residual root. And the FBs were surgically removed with no postoperative complications. Through comparison, it was found that the degree of swelling on day 2 postoperatively was significantly different between the grid group and the non-grid group (P < 0.05). CONCLUSIONS: This study demonstrates that a radiographic grid with mark points is a more efficient approach compared with traditional methods for FBs removal, and this surgical method is more accurate, fast and noninvasive.


Assuntos
Face , Corpos Estranhos , Feminino , Masculino , Humanos , Adulto Jovem , Adulto , Estudos Retrospectivos , China , Corpos Estranhos/diagnóstico por imagem , Corpos Estranhos/cirurgia , Vidro
6.
Neurologist ; 29(2): 82-90, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37839086

RESUMO

OBJECTIVES: Spinal cord injury (SCI) is any spinal cord injury or affliction that results in temporary or permanent impairment of motor or sensory function. This study determined the prevalence of frailty and its impact on in-hospital outcomes of patients admitted with acute traumatic SCI (TSCI). METHODS: This retrospective study extracted data of adults 18 to 85 years with acute TSCI from the US Nationwide Inpatient Sample (NIS) 2016 to 2018. Frailty status were assessed by the 11-factor modified Frailty Index (mFI-11) through claim codes. Patients with an mFI ≥3 were classified as frail. Associations between study variables and in-hospital mortality, discharge status, prolonged length of stay, severe infection, and hospital costs were determined by univariate and multivariable regression analyses. RESULTS: A total of 52,263 TSCI patients were identified, where 12,203 (23.3%) patients were frail. After adjusting for relevant confounders, frailty was independently associated with increased risk for in-hospital mortality [adjusted odds ratio (aOR) = 1.25, 95% CI:1.04-1.49], unfavorable discharge (aOR =1.15, 95% CI: 1.09-1.22), prolonged length of stay (aOR =1.32, 95% CI: 1.24-1.40), and severe infection (aOR =2.52, 95% CI: 2.24-2.83), but not hospital cost. Stratified analyses revealed frailty was associated with higher unfavorable discharge and severe infection regardless of age, Charlson Comorbidity Index, and injury level. CONCLUSIONS: In acute TSCI, frailty is independently associated with increased risk for adverse inpatient outcomes in terms of in-hospital mortality, prolonged hospital stays, unfavorable discharge, and particularly severe infection.


Assuntos
Fragilidade , Traumatismos da Medula Espinal , Adulto , Humanos , Fragilidade/epidemiologia , Fragilidade/complicações , Estudos Retrospectivos , Pacientes Internados , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/epidemiologia , Hospitalização , Tempo de Internação , Complicações Pós-Operatórias/etiologia , Fatores de Risco
7.
Plant Biotechnol J ; 22(3): 759-773, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37937736

RESUMO

Soybean is one of the most economically important crops worldwide and an important source of unsaturated fatty acids and protein for the human diet. Consumer demand for healthy fats and oils is increasing, and the global demand for vegetable oil is expected to double by 2050. Identification of key genes that regulate seed fatty acid content can facilitate molecular breeding of high-quality soybean varieties with enhanced fatty acid profiles. Here, we analysed the genetic architecture underlying variations in soybean seed fatty acid content using 547 accessions, including mainly landraces and cultivars from northeastern China. Through fatty acid profiling, genome re-sequencing, population genomics analyses, and GWAS, we identified a SEIPIN homologue at the FA9 locus as an important contributor to seed fatty acid content. Transgenic and multiomics analyses confirmed that FA9 was a key regulator of seed fatty acid content with pleiotropic effects on seed protein and seed size. We identified two major FA9 haplotypes in 1295 resequenced soybean accessions and assessed their phenotypic effects in a field planting of 424 accessions. Soybean accessions carrying FA9H2 had significantly higher total fatty acid contents and lower protein contents than those carrying FA9H1 . FA9H2 was absent in wild soybeans but present in 13% of landraces and 26% of cultivars, suggesting that it may have been selected during soybean post-domestication improvement. FA9 therefore represents a useful genetic resource for molecular breeding of high-quality soybean varieties with specific seed storage profiles.


Assuntos
Ácidos Graxos , Glycine max , Humanos , Ácidos Graxos/metabolismo , Glycine max/genética , Ácidos Graxos Insaturados/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Óleos de Plantas/metabolismo , Sementes/genética , Sementes/metabolismo
8.
J Hazard Mater ; 465: 133263, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38118200

RESUMO

Lead (Pb) and cadmium (Cd) are common heavy metal pollutants that are often found in the soil in soybean agricultural production, adversely impacting symbiotic nitrogen fixation in soybean nodules. In this study, the exposure of soybean nodules to Pb and Cd stress was found to reduce nitrogenase activity. Shifts in the RNA methylation profiles of nodules were subsequently examined by profiling the differential expression of genes responsible for regulating m6A modifications and conducting transcriptome-wide analyses of m6A methylation profiles under Pb and Cd stress condition. Differentially methylated genes (DMGs) that were differentially expressed were closely related to reactive oxygen species activity and integral membrane components. Overall, 19 differentially expressed DMGs were ultimately determined to be responsive to both Pb and Cd stress, including Glyma.20G082450, which encodes GmAMT1;1 and was confirmed to be a positive regulator of nodules tolerance to Pb and Cd. Together, these results are the first published data corresponding to transcriptome-wide m6A methylation patterns in soybean nodules exposed to Cd and Pb stress, and provide novel molecular insight into the regulation of Pb and Cd stress responses in nodules, highlighting promising candidate genes related to heavy metal tolerance, that may also be amenable to application in agricultural production. ENVIRONMENTAL IMPLICATIONS: Lead (Pb) and cadmium (Cd) are prevalent heavy metal pollutants in soil, and pose a major threat to crop production, food security and human health. Here, MeRIP-seq approach was employed to analyze the regulatory network activated in soybean nodules under Pb and Cd stress, ultimately leading to the identification of 19 shared differentially expressed DMGs. When overexpressed, GmATM1;1 was found to enhance the Pb and Cd tolerance of soybean nodules. These results provide a theoretical basis for studies on tolerance to heavy metals in symbiotic nitrogen fixation, and provide an approach to enhancing Pb and Cd tolerance in soybean production.


Assuntos
Poluentes Ambientais , Metais Pesados , Poluentes do Solo , Humanos , Cádmio/metabolismo , Transcriptoma , Glycine max , Chumbo , Metais Pesados/metabolismo , Metilação , Solo , Poluentes do Solo/metabolismo
9.
Sci Rep ; 13(1): 22723, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38123709

RESUMO

For the robust fault-tolerant control of the controllable suspension system, a control strategy driven by knowledge-data fusion is proposed. Firstly, the boundary fuzziness between perturbation type uncertainty and gain type fault is analyzed, and then a data-driven method is introduced to avoid the state estimation of system uncertainty and fault. The proximal policy optimization algorithm in reinforcement learning is selected to construct a "data control law", to deal with uncertainty and fault. On the other hand, based on the classical sky-hook control, the "knowledge control law" for system performance optimization is designed, taking into account the nonlinear and non-stationary characteristics of the system. Furthermore, the dependency between robust fault tolerance and performance optimization control is revealed, and the two control laws are fused by numerical multiplication, to realize the performance matching optimization control of robust fault tolerance of controllable suspension system driven by knowledge-data fusion. Finally, the effectiveness and feasibility of the proposed method are verified by the simulation and real-time experiment of non-stationary excitation and near-stationary excitation under the combination of uncertainty and fault.

10.
Sensors (Basel) ; 23(24)2023 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-38139722

RESUMO

Environmental perception plays a fundamental role in decision-making and is crucial for ensuring the safety of autonomous driving. A pressing challenge is the online evaluation of perception uncertainty, a crucial step towards ensuring the safety and the industrialization of autonomous driving. High-definition maps offer precise information about static elements on the road, along with their topological relationships. As a result, the map can provide valuable prior information for assessing the uncertainty associated with static elements. In this paper, a method for evaluating perception uncertainty online, encompassing both static and dynamic elements, is introduced based on the high-definition map. The proposed method is as follows: Firstly, the uncertainty of static elements in perception, including the uncertainty of their existence and spatial information, was assessed based on the spatial and topological features of the static environmental elements; secondly, an online assessment model for the uncertainty of dynamic elements in perception was constructed. The online evaluation of the static element uncertainty was utilized to infer the dynamic element uncertainty, and then a model for recognizing the driving scenario and weather conditions was constructed to identify the triggering factors of uncertainty in real-time perception during autonomous driving operations, which can further optimize the online assessment model for perception uncertainty. The verification results on the nuScenes dataset show that our uncertainty assessment method based on a high-definition map effectively evaluates the real-time perception results' performance.

11.
Radiology ; 309(2): e230681, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37962500

RESUMO

Background Iodinated contrast agents (ICAs), which are widely used in CT angiography (CTA), may cause adverse effects in humans, and their use is time-consuming and costly. Purpose To develop an ICA-free deep learning imaging model for synthesizing CTA-like images and to assess quantitative and qualitative image quality as well as the diagnostic accuracy of synthetic CTA (Syn-CTA) images. Materials and Methods A generative adversarial network (GAN)-based CTA imaging model was trained, validated, and tested on retrospectively collected pairs of noncontrast CT and CTA images of the neck and abdomen from January 2017 to June 2022, and further validated on an external data set. Syn-CTA image quality was evaluated using quantitative metrics. In addition, two senior radiologists scored the visual quality on a three-point scale (3 = good) and determined the vascular diagnosis. The validity of Syn-CTA images was evaluated by comparing the visual quality scores and diagnostic accuracy of aortic and carotid artery disease between Syn-CTA and real CTA scans. Results CT scans from 1749 patients (median age, 60 years [IQR, 50-68 years]; 1057 male patients) were included in the internal data set: 1137 for training, 400 for validation, and 212 for testing. The external validation set comprised CT scans from 42 patients (median age, 67 years [IQR, 59-74 years]; 37 male patients). Syn-CTA images had high similarity to real CTA images (normalized mean absolute error, 0.011 and 0.013 for internal and external test set, respectively; peak signal-to-noise ratio, 32.07 dB and 31.58 dB; structural similarity, 0.919 and 0.906). The visual quality of Syn-CTA and real CTA images was comparable (internal test set, P = .35; external validation set, P > .99). Syn-CTA showed reasonable to good diagnostic accuracy for vascular diseases (internal test set: accuracy = 94%, macro F1 score = 91%; external validation set: accuracy = 86%, macro F1 score = 83%). Conclusion A GAN-based model that synthesizes neck and abdominal CTA-like images without the use of ICAs shows promise in vascular diagnosis compared with real CTA images. Clinical trial registration no. NCT05471869 © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Zhang and Turkbey in this issue.


Assuntos
Aorta , Angiografia por Tomografia Computadorizada , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Artérias Carótidas
12.
Front Neurol ; 14: 1251833, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37869136

RESUMO

Respiratory difficulties and mortality following severe cervical spinal cord injury (CSCI) result primarily from malfunctions of respiratory pathways and the paralyzed diaphragm. Nonetheless, individuals with CSCI can experience partial recovery of respiratory function through respiratory neuroplasticity. For decades, researchers have revealed the potential mechanism of respiratory nerve plasticity after CSCI, and have made progress in tissue healing and functional recovery. While most existing studies on respiratory plasticity after spinal cord injuries have focused on the cervical spinal cord, there is a paucity of research on respiratory-related brain structures following such injuries. Given the interconnectedness of the spinal cord and the brain, traumatic changes to the former can also impact the latter. Consequently, are there other potential therapeutic targets to consider? This review introduces the anatomy and physiology of typical respiratory centers, explores alterations in respiratory function following spinal cord injuries, and delves into the structural foundations of modified respiratory function in patients with CSCI. Additionally, we propose that magnetic resonance neuroimaging holds promise in the study of respiratory function post-CSCI. By studying respiratory plasticity in the brain and spinal cord after CSCI, we hope to guide future clinical work.

13.
Front Pediatr ; 11: 1263280, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37881636

RESUMO

Objective: Pediatric spinal cord injury without radiographic abnormality (SCIWORA) caused by backbend practice is increasing. This study proposed an underlying 'combined injury mechanism' related to the spinal cord and femoral nerve overstretching. Methods: Pediatric patients diagnosed with backbend-associated SCIWORA at the China Rehabilitation Research Center during 2017-2021 were recruited. Clinical and imaging data were collected, and each patient's clinical course and prognosis were determined. Healthy dancers were recruited to simulate the backbend, obtain images, and estimate the spinal cord and femoral nerve stretch ratio. A model for the 'combined injury mechanism' was established using 4-week-old SD rats. Results: Forty-two SCIWORA female patients with an average age of 6 (SD 1) years and an average hospitalization time of 91 (SD 43) days were assessed. The primary initial symptom was pain in the back and/or lower extremities (33, 79%). The average time from injury onset to severe paralysis was 2.0 (SD 0.6) hours. Most patients had complete paraplegia (32, 76%), and neurological levels were distributed mainly in thoracic segments (38, 91%). Patients with elicited tendon reflexes on admission tended to have an incomplete spinal cord injury (p = 0.001) and improved motor recovery (p = 0.018). After one year, the most common complications were scoliosis (31, 74%) and abnormal hips (14, 33%). Injury of the caudal spinal cord torn by nerve roots was confirmed by surgical exploration in a case. The thoracic spinal cord and femoral nerves were overstretched by 148.8 ± 3.6% and111.7 ± 4.0%, respectively, in a full backbend posture. The 'combined injury mechanism' was partially replicated in the animal model. Conclusion: Spinal overstretch and transient dislocation are considered the primary mechanisms by which SCIWORA occurs in children. Overstretching the femoral nerve aggravates spinal cord injuries caused by backbend practice.

14.
Int J Mol Sci ; 24(9)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37175456

RESUMO

Soybean is a cereal crop with high protein and oil content which serves as the main source of plant-based protein and oil for human consumption. The symbiotic relationship between legumes and rhizobia contributes significantly to soybean yield and quality, but the underlying molecular mechanisms remain poorly understood, hindering efforts to improve soybean productivity. In this study, we conducted a transcriptome analysis and identified 22 differentially expressed genes (DEGs) from nodule-related quantitative trait loci (QTL) located in chromosomes 12 and 19. Subsequently, we performed functional characterisation and haplotype analysis to identify key candidate genes among the 22 DEGs that are responsive to nitrate. Our findings identified GmTCP (TEOSINTE-BRANCHED1/CYCLOIDEA/PCF) and GmNLP (NIN-LIKE PROTEIN) as the key candidate genes that regulate the soybean nodule phenotype in response to nitrogen concentration. We conducted homologous gene mutant analysis in Arabidopsis thaliana, which revealed that the homologous genes of GmTCP and GmNLP play a vital role in regulating root development in response to nitrogen concentration. We further performed overexpression and gene knockout of GmTCP and GmNLP through hairy root transformation in soybeans and analysed the effects of GmTCP and GmNLP on nodulation under different nitrogen concentrations using transgenic lines. Overexpressing GmTCP and GmNLP resulted in significant differences in soybean hairy root nodulation phenotypes, such as nodule number (NN) and nodule dry weight (NDW), under varying nitrate conditions. Our results demonstrate that GmTCP and GmNLP are involved in regulating soybean nodulation in response to nitrogen concentration, providing new insights into the mechanism of soybean symbiosis establishment underlying different nitrogen concentrations.


Assuntos
Arabidopsis , Nodulação , Humanos , Nodulação/genética , Glycine max/metabolismo , Nitratos/metabolismo , Nitrogênio/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Simbiose/genética , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas
16.
Sensors (Basel) ; 23(5)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36905068

RESUMO

Deep neural network algorithms have achieved impressive performance in object detection. Real-time evaluation of perception uncertainty from deep neural network algorithms is indispensable for safe driving in autonomous vehicles. More research is required to determine how to assess the effectiveness and uncertainty of perception findings in real-time.This paper proposes a novel real-time evaluation method combining multi-source perception fusion and deep ensemble. The effectiveness of single-frame perception results is evaluated in real-time. Then, the spatial uncertainty of the detected objects and influencing factors are analyzed. Finally, the accuracy of spatial uncertainty is validated with the ground truth in the KITTI dataset. The research results show that the evaluation of perception effectiveness can reach 92% accuracy, and a positive correlation with the ground truth is found for both the uncertainty and the error. The spatial uncertainty is related to the distance and occlusion degree of detected objects.

17.
Sci Rep ; 12(1): 13203, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35915140

RESUMO

To improve the multidirectional motion control accuracy and driving stability of Distributed Drive Autonomous Vehicles (DDAVs) under extreme conditions, the extreme speed estimation method based on dynamic boundary and the multidirectional motion coupling control law design method based on multi degrees of freedom vehicle dynamic model are proposed. The extreme speed estimation method identifies the stable state of DDAVs by the dynamic boundary composed of yaw rate, sideslip angle and roll angle, and then estimates the extreme speed of the vehicle. The design method of multidirectional motion coupling control law adopts eight-degrees-of-freedom (8-DOF) vehicle dynamic model to design path tracking control law, speed tracking control law, yaw stability control law, and active suspension control law at the same time, so as to realize multidirectional motion coupling control. Based on the above method, the Multidirectional Motion Coupling Control System (MMCCS) of DDAVs is designed. The effectiveness of the proposed method is verified by double-line-shifting and serpentine driving simulations under different road adhesion conditions. The superiority of the method is proved by comparing the existing integrated control method.

18.
Front Plant Sci ; 13: 869455, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35783974

RESUMO

Genetic populations provide the basis for genetic and genomic research, and chromosome segment substitution lines (CSSLs) are a powerful tool for the fine mapping of quantitative traits, new gene mining, and marker-assisted breeding. In this study, 213 CSSLs were obtained by self-crossing, backcrossing, and marker-assisted selection between cultivated soybean (Glycine max [L.] Merr.) variety Suinong14 (SN14) and wild soybean (Glycine soja Sieb. et Zucc.) ZYD00006. The genomes of these 213 CSSLs were resequenced and 580,524 single-nucleotide polymorphism markers were obtained, which were divided into 3,780 bin markers. The seed-pod-related traits were analyzed by quantitative trait locus (QTL) mapping using CSSLs. A total of 170 QTLs were detected, and 32 QTLs were detected stably for more than 2 years. Through epistasis analysis, 955 pairs of epistasis QTLs related to seed-pod traits were obtained. Furthermore, the hundred-seed weight QTL was finely mapped to the region of 64.4 Kb on chromosome 12, and Glyma.12G088900 was identified as a candidate gene. Taken together, a set of wild soybean CSSLs was constructed and upgraded by a resequencing technique. The seed-pod-related traits were studied by bin markers, and a candidate gene for the hundred-seed weight was finely mapped. Our results have revealed the CSSLs can be an effective tool for QTL mapping, epistatic effect analysis, and gene cloning.

19.
Front Genet ; 13: 889795, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692823

RESUMO

Type III effectors secreted by rhizobia regulate nodulation in the host plant and are important modulators of symbiosis between rhizobia and soybean (Glycine max), although the underlying mechanisms are poorly understood. Here, we studied the type III effector NopAA in Sinorhizobium fredii HH103, confirming its secretion into the extracellular environment under the action of genistein. The enzyme activity of NopAA was investigated in vitro, using xyloglucan and ß-glucan as substrates. NopAA functions were investigated by the generation of a NopAA mutant and the effects of NopAA deficiency on symbiosis were analyzed. Soybean genes associated with NopAA were identified in a recombinant inbred line (RIL) population and their functions were verified. NopAA was confirmed to be a type III effector with glycosyl hydrolase activity, and its mutant did not promote nodulation. Quantitative trait locus (QTL) analysis identified 10 QTLs with one, Glyma.19g074200 (GmARP), found to be associated with NopAA and to positively regulate the establishment of symbiosis. All these results support the hypothesis that type III effectors interact with host proteins to regulate the establishment of symbiosis and suggest the possibility of manipulating the symbiotic soybean-rhizobia interaction to promote efficient nitrogen fixation.

20.
Neural Regen Res ; 17(12): 2702-2709, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35662217

RESUMO

Ferroptosis is a recently discovered form of iron-dependent cell death, which occurs during the pathological process of various central nervous system diseases or injuries, including secondary spinal cord injury. Selenium has been shown to promote neurological function recovery after cerebral hemorrhage by inhibiting ferroptosis. However, whether selenium can promote neurological function recovery after spinal cord injury as well as the underlying mechanism remain poorly understood. In this study, we injected sodium selenite (3 µL, 2.5 µM) into the injury site of a rat model of T10 vertebral contusion injury 10 minutes after spinal cord injury modeling. We found that sodium selenite treatment greatly decreased iron concentration and levels of the lipid peroxidation products malondialdehyde and 4-hydroxynonenal. Furthermore, sodium selenite increased the protein and mRNA expression of specificity protein 1 and glutathione peroxidase 4, promoted the survival of neurons and oligodendrocytes, inhibited the proliferation of astrocytes, and promoted the recovery of locomotive function of rats with spinal cord injury. These findings suggest that sodium selenite can improve the locomotive function of rats with spinal cord injury possibly through the inhibition of ferroptosis via the specificity protein 1/glutathione peroxidase 4 pathway.

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