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1.
Nat Biomed Eng ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745110

RESUMO

Technology for spatial multi-omics aids the discovery of new insights into cellular functions and disease mechanisms. Here we report the development and applicability of multi-omics in situ pairwise sequencing (MiP-seq), a method for the simultaneous detection of DNAs, RNAs, proteins and biomolecules at subcellular resolution. Compared with other in situ sequencing methods, MiP-seq enhances decoding capacity and reduces sequencing and imaging costs while maintaining the efficacy of detection of gene mutations, allele-specific expression and RNA modifications. MiP-seq can be integrated with in vivo calcium imaging and Raman imaging, which enabled us to generate a spatial multi-omics atlas of mouse brain tissues and to correlate gene expression with neuronal activity and cellular biochemical fingerprints. We also report a sequential dilution strategy for resolving optically crowded signals during in situ sequencing. High-throughput in situ pairwise sequencing may facilitate the multidimensional analysis of molecular and functional maps of tissues.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38684137

RESUMO

OBJECTIVE: To investigate the effects of core strengthening exercises on pain, mobility, and lower extremity muscle strength in patients with Patellofemoral Pain Syndrome (PFP). DESIGN: Six databases were searched from inception until August 11, 2023. Pain, function and muscle strength related outcomes were extracted and the quality of the studies was assessed using the PEDro scale and the level of evidence was assessed using the GRADE. RESULTS: Nineteen studies involving 1138 patients were included. Very low-grade evidence supported the short-term pain-relieving effect of core training (SMD = -0.60 95% CI [-0.95, -0.25]), high-grade evidence supported the short-term functional improvement effects of core training (WMD = 3.61 95% CI [1.44, 5.78]), which was similarly significant within 3-12 months of follow-up. The results of the subgroup analyses suggested that hip-knee training was most advantageous in relieving pain and enhancing motor function. CONCLUSIONS: Although training that includes trunk core is clearly superior to knee strengthening alone, the effectiveness of hip-knee training, which is also a core training program for pain and function, is more pronounced. The available evidence supports that hip-knee training is the most valuable treatment option for patients with PFP.

3.
Front Neurosci ; 18: 1304906, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38486971

RESUMO

Introduction: Cerebral ischaemic stroke is a common disease that poses a serious threat to human health. Butyrate is an important metabolite of intestinal microorganisms. Recent studies have shown that butyrate has a significant protective effect in animal models of cerebral ischaemic injury. Objective: The aim of this study was to evaluate the protective effect of butyrate on cerebral ischaemic stroke by meta-analysis, aiming to provide a scientific basis for the clinical application of butyrate in patients with cerebral ischaemia. Materials and methods: A systematic search was conducted for all relevant studies published before 23 January 2024, in PubMed, Web of Science, Cochrane Library, and Embase. Methodological quality was assessed using Syrcle's risk of bias tool for animal studies. Data were analysed using Rev Man 5.3 software. Results: A total of nine studies were included, and compared with controls, butyrate significantly increased BDNF levels in the brain (SMD = 2.33, 95%CI = [1.20, 3.47], p < 0.005) and P-Akt expression (SMD = 3.53, 95% CI = [0.97, 6.10], p < 0.05). Butyrate also decreased IL-ß levels in the brain (SMD = -2.02, 95% CI = [-3.22, -0.81], p < 0.005), TNF-α levels (SMD = -0.86, 95% CI = [-1.60, -0.12], p < 0.05), and peripheral vascular IL-1ß levels (SMD = -2.10, 95%CI = [-3.59, -0.61], p < 0.05). In addition, butyrate reduced cerebral infarct volume (MD = -11.29, 95%CI = [-17.03, -5.54], p < 0.05), mNSS score (MD = -2.86, 95%CI = [-4.12, -1.60], p < 0.005), foot fault score (MD = -7.59, 95%CI = [-9.83, -5, 35], p < 0.005), and Morris water maze time (SMD = -2.49, 95%CI = [-4.42, -0.55], p < 0.05). Conclusion: The results of this study indicate that butyrate has a protective effect on cerebral ischaemic stroke in animal models, and the mechanism is related to reducing inflammation and inhibiting apoptosis. It provides an evidence-based basis for the future clinical development of butyrate in the treatment of ischaemic stroke. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/, CRD42023482844.

4.
PLoS One ; 19(3): e0299805, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38512903

RESUMO

The automatic cutting of coal and rock surface morphology modeling based on the actual geological environment of coal mine underground excavation and mining is of great significance for improving the surface quality of coal and rock after cutting and enhancing the safety and stability of advanced support. To this end, using the principle of coordinate transformation, the kinematic trajectory of the cutting head of the tunneling machine is established, and the contour morphology of the cutting head under variable cutting technology is obtained. Then, based on the regenerative vibration theory of the cutting head, a dynamic model of the cutting head coal wall is established, and the coordinate relationship of the cutting head in the tunnel coordinate system under vibration induction is analyzed. Based on fractal theory and Z-MAP method, a simulation method for the surface morphology of coal and rock after cutting is proposed, which is driven by the cutting trajectory Under the coupling effect of cutting vibration induction and random fragmentation of coal and rock, simulation of the surface morphology of comprehensive excavation tunnels was conducted, and relevant experiments were conducted to verify the results. A 1:3 similarity experimental model of EBZ160 tunneling machine was used to build a cutting head coal and rock system cutting experimental platform for comparative experiments of cutting morphology. Furthermore, statistical methods were used to compare and evaluate the simulated roof with the actual roof. The results show that the relative errors between the maximum range of peaks and valleys, the peak skewness coefficient of height standard deviation, and the kurtosis coefficient of the actual roof are 1.3%, 24.5%, 16%, and 2.9%, respectively. Overall, this indicates that the surface morphology distribution characteristics of the simulated roof and the actual roof are similar, verifying the effectiveness of the modeling and simulation method proposed in this paper, and providing theoretical support for the design and optimization of advanced support in the future.


Assuntos
Carvão Mineral , Traumatismos Craniocerebrais , Humanos , Simulação por Computador , Meio Ambiente , Fractais
5.
Int J Biol Macromol ; 260(Pt 1): 129339, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218287

RESUMO

Glyphodes pyloalis (Lepidoptera: Pyralidae) is one of the major pests in mulberry production in China, which has developed resistance to various insecticides. Chemoreception is one of the most crucial physiological tactics in insects, playing a pivotal role in recognizing chemical stimuli in the environment, including noxious stimuli such as insecticides. Herein, we obtained recombinant pheromone-binding protein 1 (GpylPBP1) that exhibited antennae-biased expression in G. pyloalis. Ligand-binding assays indicated that GpylPBP1 had the binding affinities to two organophosphorus insecticides, with a higher binding affinity to chlorpyrifos than to phoxim. Computational simulations showed that a mass of nonpolar amino acid residues formed the binding pocket of GpylPBP1 and contributed to the hydrophobic interactions in the bindings of GpylPBP1 to both insecticides. Furthermore, the binding affinities of three GpylPBP1 mutants (F12A, I52A, and F118A) to both insecticides were all significantly reduced compared to those of the GpylPBP1-wild type, suggesting that Phe12, Ile52, and Phe118 residues were crucial binding sites and played crucial roles in the bindings of GpylPBP1 to both insecticides. Our findings can be instrumental in elucidating the effects of insecticides on olfactory recognition in moths and facilitating the development of novel pest management strategies using PBPs as targets based on insect olfaction.


Assuntos
Inseticidas , Mariposas , Animais , Inseticidas/metabolismo , Proteínas de Transporte/metabolismo , Feromônios/metabolismo , Compostos Organofosforados/metabolismo , Mariposas/metabolismo , Proteínas Recombinantes/química , Proteínas de Insetos/metabolismo
6.
Biomimetics (Basel) ; 9(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38248590

RESUMO

Analysis of pedestrians' head and lower limb injuries at the tissue level is lacking in studies of tram-pedestrian collisions. The purpose of this paper therefore to investigate the impact response process and severity of pedestrians' injuries in tram-pedestrian collisions, using the Total Human Model for Safety (THUMS) pedestrian human body model together with the tram FE model. Two full-scale tram-pedestrian dummy crash tests were performed to validate the FE model, and the total correlation and analysis (CORA) score of head acceleration yielded values of 0.840 and 0.734, confirming a strong agreement between the FE-simulated head responses and the experimental head kinematics. The effects of different tram speeds and impact angles on pedestrians' impact response injuries and the differences were further analyzed. The results indicate that direct impact of the lower limb with the tram's obstacle deflector leads to lower limb bone shaft fractures and knee tissue damage. Neck fling contributed to worsened head injury. Coup contusions were the predominant type of brain contusion, surpassing contrecoup contusions, while diffuse axonal injury was mainly concentrated in the collision-side region of the brain. Pedestrians' injuries are influenced by tram velocity and impact angle: higher tram velocities increase the risk of lower limb and head injuries. The risk of head injury for pedestrians is higher when the impact angle is negative, while lower limb injuries are more significant when the impact angle is 0°. This study provides practical guidance for enhancing tram safety and protecting pedestrians.

7.
Int Immunopharmacol ; 127: 111326, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38091828

RESUMO

Cuproptosis is a new manner of mitochondrial cell death induced by copper. There is evidence that serum copper has a crucial impact on ankylosing spondylitis (AS) by copper-induced inflammatory response. However, the molecular mechanisms of cuproptosis modulators in AS remain unknown. We aimed to use a bioinformatics-based method to comprehensively investigate cuproptosis-related subtype identification and immune microenvironment infiltration of AS. Additionally, we further verified the results by in vitro experiments, in which peripheral blood and fibroblast cells from AS patients were used to evaluate the functions of significant cuproptosis modulators on AS. Finally, eight significant cuproptosis modulators were identified by analysis of differences between controls and AS cases from GSE73754 dataset. Eight prognostic cuproptosis modulators (LIPT1, DLD, PDHA1, PDHB, SLC31A1, ATP7A, MTF1, CDKN2A) were identified using a random forest model for prediction of AS risk. A nomogram model of the 8 prognostic cuproptosis modulators was then constructed; the model could be beneficial in clinical settings, as indicated by decision curve analysis. Consensus clustering analysis was used to divide AS patients into two cuproptosis subtypes (clusterA & B) according to significant cuproptosis modulators. The cuproptosis score of each sample was calculated by principal component analysis to quantify cuproptosis subtypes. The cuproptosis scores were higher in clusterB than in clusterA. Additionally, cases in clusterA were closely associated with the immunity of activated B cells, Activated CD4 T cell, Type17 T helper cell and Type2 T helper cell, while cases in clusterB were linked to Mast cell, Neutrophil, Plasmacytoid dendritic cell immunity, indicating that clusterB may be more correlated with AS. Notably, key cuproptosis genes including ATP7A, MTF1, SLC31A1 detected by RT-qPCR with peripheral blood exhibited significantly higher expression levels in AS cases than controls; LIPT1 showed the opposite results; High MTF1 expression is correlated with increased osteogenic capacity. In general, this study of cuproptosis patterns may provide promising biomarkers and immunotherapeutic strategies for future AS treatment.


Assuntos
Cobre , Espondilite Anquilosante , Humanos , Linfócitos B , Linfócitos T CD4-Positivos , Análise por Conglomerados , Apoptose
8.
J Hazard Mater ; 465: 133138, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38086304

RESUMO

Phenanthrene, a typical chemical of polycyclic aromatic hydrocarbons (PAHs) pollutants, severely threatens health of wild life and human being. Microbial degradation is effective and environment-friendly for PAH removal, while the phenanthrene-degrading mechanism in Gram-positive bacteria is unclear. In this work, one Gram-positive strain of plant growth-promoting rhizobacteria (PGPR), Pseudarthrobacter sp. L1SW, was isolated and identified with high phenanthrene-degrading efficiency and great stress tolerance. It degraded 96.3% of 500 mg/L phenanthrene in 72 h and kept stable degradation performance with heavy metals (65 mg/L of Zn2+, 5.56 mg/L of Ni2+, and 5.20 mg/L of Cr3+) and surfactant (10 CMC of Tween 80). Strain L1SW degraded phenanthrene mainly through phthalic acid pathway, generating intermediate metabolites including cis-3,4-dihydrophenanthrene-3,4-diol, 1-hydroxy-2-naphthoic acid, and phthalic acid. A novel metabolite (m/z 419.0939) was successfully separated and identified as an end-product of phenanthrene, suggesting a unique metabolic pathway. With the whole genome sequence alignment and comparative genomic analysis, 19 putative genes associated with phenanthrene metabolism in strain L1SW were identified to be distributed in three gene clusters and induced by phenanthrene and its metabolites. These findings advance the phenanthrene-degrading study in Gram-positive bacteria and promote the practical use of PGPR strains in the bioremediation of PAH-contaminated environments.


Assuntos
Fenantrenos , Ácidos Ftálicos , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Fenantrenos/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Ácidos Ftálicos/metabolismo , Biodegradação Ambiental
9.
Plant Commun ; 5(1): 100680, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37660252

RESUMO

Tropane alkaloids (TAs), which are anticholinergic agents, are an essential class of natural compounds, and there is a growing demand for TAs with anesthetic, analgesic, and spasmolytic effects. Anisodus acutangulus (Solanaceae) is a TA-producing plant that was used as an anesthetic in ancient China. In this study, we assembled a high-quality, chromosome-scale genome of A. acutangulus with a contig N50 of 7.4 Mb. A recent whole-genome duplication occurred in A. acutangulus after its divergence from other Solanaceae species, which resulted in the duplication of ADC1 and UGT genes involved in TA biosynthesis. The catalytic activities of H6H enzymes were determined for three Solanaceae plants. On the basis of evolution and co-expressed genes, AaWRKY11 was selected for further analyses, which revealed that its encoded transcription factor promotes TA biosynthesis by activating AaH6H1 expression. These findings provide useful insights into genome evolution related to TA biosynthesis and have potential implications for genetic manipulation of TA-producing plants.


Assuntos
Anestésicos , Solanaceae , Tropanos/análise , Tropanos/metabolismo , Solanaceae/genética , Solanaceae/metabolismo , Cromossomos/química , Cromossomos/metabolismo , Anestésicos/metabolismo , China
11.
J Orthop Surg Res ; 18(1): 921, 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38042802

RESUMO

OBJECTIVE: To conduct a systematic review and meta-analysis to investigate the clinical efficacy of acupuncture combined with active exercise training in improving pain and function of knee osteoarthritis (KOA) individuals. DATA SOURCES: PubMed, EMBASE, The Cochrane Library, Web of Science, China National Knowledge Infrastructure, Wan Fang Data, Technology Periodical Database and China Biology Medicine were searched from their inceptions to April 5, 2023. REVIEW METHODS: We analyzed trials of acupuncture combined with active exercise training for KOA. The included studies were of high quality (Jadad ≥ 4) and RCTs. Study selection, data extraction, risk of bias and quality assessment were independently performed by two reviewers. We performed systematic analyses based on different outcome measures, including total efficiency rate, visual analogue scale (VAS), the Western Ontario and Mcmaster Universities Osteoarthritis Index (WOMAC), the Lysholm Knee Scale (LKS) and range of motion (ROM). We used Review Manager 5.3 and Stata/MP 14.0 to analyze the data. And it was verified by trial sequence analysis (TSA). If I2 > 50% and p < 0.05, we performed sensitivity analysis and subgroup analysis to find the source of heterogeneity. Publication bias was studied by funnel plot and Egger's test was used to verify it. RESULTS: Full 11 high-quality studies (Jadad ≥ 4) including 774 KOA individuals were included in this review for meta-analysis. The results showed that acupuncture combined with active exercise training (combined group) was superior to the acupuncture group in improving the total effective rate [RR = 1.13, 95%CI (1.05, 1.22), I2 = 0%, P = 0.70], reducing the pain level (VAS) [MD = - 0.74, 95%CI (- 1.04, - 0.43), I2 = 68%, P < 0.05], improving knee joint function (WOMAC) [MD = - 6.97, 95%CI (- 10.74, - 3.19), I2 = 76%, P < 0.05] and improving joint range of motion (ROM) [MD = 6.25, 95%CI (2.37, 10.04), I2 = 0%, P = 0.71]. Similarly, the combined group showed significant improvements in the total effective rate [RR = 1.31, 95% CI (1.18, 1.47), I2 = 48%, P = 0.10], pain (VAS) [MD = 1.42, 95% CI (- 1.85, - 1.00), I2 = 65%, P = 0.02] and knee function (WOMAC) [MD = 7.05, 95% CI (- 11.43, - 2.66), I2 = 86%, P < 0.05] compared with the non-acupuncture group. CONCLUSION: The combined effect of all studies showed significant benefits of acupuncture combined with active exercise training in improving the total effective rate, reducing pain, promoting recovery of knee function and expanding range of motion. However, some evaluation indicators are highly subjective and need to be further confirmed by more objective and evidence-based high-quality RCTs in future. SYSTEMATIC REVIEW REGISTRATION: [PROSPERO], identifier [No. CRD42023425823].


Assuntos
Terapia por Acupuntura , Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/terapia , Dor , Articulação do Joelho , Exercício Físico
12.
Molecules ; 28(23)2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38067412

RESUMO

Euphorbia dentata (Euphorbiaceae), an invasive weed, is rarely eaten by herbivorous insects and could secrete a large amount of white latex, causing a serious threat to local natural vegetation, agricultural production and human health. In order to prevent this plant from causing more negative effects on humans, it is necessary to understand and utilize the chemical relationships between the latex of E. dentata and herbivorous insects. In this study, three new norsesquiterpenes (1-3), together with seven known analogues (4-10), were isolated and identified from the latex of E. dentata. All norsesquiterpenes (1-10) showed antifeedant and growth-inhibitory effects on H. armigera with varying levels, especially compounds 1 and 2. In addition, the action mechanisms of active compounds (1-3) were revealed by detoxifying enzyme (AchE, CarE, GST and MFO) activities and corresponding molecular docking analyses. Our findings provide a new idea for the development and utilization of the latex of E. dentata, as well as a potential application of norsesquiterpenes in botanical insecticides.


Assuntos
Euphorbia , Látex , Humanos , Mecanismos de Defesa , Euphorbia/química , Helicoverpa armigera , Látex/química , Simulação de Acoplamento Molecular , Animais
13.
Biomimetics (Basel) ; 8(8)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38132507

RESUMO

To study the perforation performance of CFRP laminates for rail vehicles under high-velocity impact from foreign objects, impact tests on CFRP laminates at a velocity of 163 m/s were carried out, and a corresponding finite element model was established using ABAQUS and verified. The user-defined material subroutine combined the material strain rate hardening effect and the 3D-Hashin damage criterion. The effects of impact velocity, impact object shape, and oblique angle on the perforation performance of CFRP laminates are discussed. Results show that impact velocity positively correlates with impact peak force and residual velocity. Laminates can be perforated by projectiles with a velocity above 120 m/s, and impact velocity greatly influences delamination below 140 m/s. Three shapes of projectile impacting laminates are considered: spherical, cylindrical, and conical. The conical projectile penetrates the laminate most easily, with the largest delamination area. The cylindrical projectile with a flat end suffers the most resistance, and the delaminated area is between the impact conditions of the conical and spherical projectiles. Increasing the angle of inclination increases the impacted area of the laminate and the extent of damage, thus dissipating more energy. The projectile fails to penetrate the laminate when the oblique angle reaches 60°. CFRP composite structures penetrated by high-speed impacts pose a significant threat to the safety of train operations, providing an opportunity for the application of bio-inspired composite structures.

14.
Front Cardiovasc Med ; 10: 1241343, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38034391

RESUMO

Objective: We aimed to evaluate the effects of different exercise rehabilitation (ER) programs on LVEF and the incidence of restenosis in patients after percutaneous coronary intervention (PCI) through a systematic review and an integrated network meta-analysis (NMA) to provide a reference for the clinical formulation of ER programs for PCI patients. Methods: Meta-analyses of the effects of different types of ER programs on LVEF and the incidence of reinfarction in post-PCI patients were retrieved from 11 domestic and foreign databases. The methodological and reporting quality of the included systematic reviews were evaluated using the AMSTAR 2 and PRISMA statements. The GRADE scoring system was used to evaluate the quality of evidence found in the studies included in the meta-analysis, and studies with high and intermediate-quality evidence were qualitatively analyzed. Stata software (version 16.0) was used to conduct an integrated NMA of the original RCTs with moderate and low risk of bias. Result: Sixteen meta-analyses were included in this evaluation. The reporting quality of the included meta-analyses was relatively complete, and the methodological quality was low. Seventy RCTs were included in the NMA. The results showed that all types of rehabilitative exercises were safe and effectively increased LVEF and reduced the incidence of coronary restenosis in patients. The comprehensive exercise program was the most likely to improve LVEF, and the comprehensive exercise program, early exercise program, and high-intensity interval exercise were better than aerobic exercise. Comprehensive exercise programs, early exercise programs, and aerobic exercise reduced the incidence of restenosis in patients. However, Chinese Qigong did not reduce the incidence of restenosis in patients, and there was a risk of bias and inconsistency in the quantitative analysis of restenosis incidence. Conclusion: Comprehensive exercise programs have the greatest therapeutic significance in improving cardiac output and reducing restenosis rates in post-PCI patients. The early exercise program has great potential but requires kinesiologists to work with physicians to structure the program and strengthen out-of-hospital management. Aerobic exercise has the least therapeutic significance, and Chinese Qigong is suitable for promotion based on its better efficacy than aerobic exercise and may be an alternative to aerobic exercise, but more experimental evidence is needed. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/, PROSPERO CRD42022374590.

15.
Front Neurol ; 14: 1278307, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38020604

RESUMO

Objective: To investigate the effects of vestibular rehabilitation training (VRT) combined with anti-vertigo drugs on vertigo and balance function in patients with vestibular neuronitis (VN). Data sources: PubMed, EMBASE, The Cochrane Library, Web of Science, CNKI, Wan Fang Data, VIP, and CBM were searched until July 13, 2023. Participants: Patients with vestibular neuronitis participated in the study. Results: Twenty one studies including 1,415 patients were included in this review for meta-analysis. According to the Physiotherapy Evidence Database (PEDro) quality assessment, four studies received high quality (≥seven scores) and 17 studies received moderate quality (six scores). The meta-analysis showed that VRT combined with anti-vertigo drugs significantly reduced the Dizziness Handicap Inventory (DHI) score, the Vestibular Disorders Activities of Daily Living Scale (VADL) score and the Canal Paresis (CP) score, and improved the overall efficiency and the Berg Balance Scale (BBS) score, promoting vestibular evoked myogenic potentials (VEMPs) returned to normal in VN compared to simple anti-vertigo drugs or VRT alone. Conclusion: The results of this meta-analysis demonstrate the efficacy and safety of VRT combined with anti-vertigo drugs in patients with VN. Combined therapy can alleviate vestibular dysfunction such as vertigo and vomiting in patients, improve daily activity ability and balance ability, in addition to VRT has fewer adverse reactions, so it is extremely safe. However, there are shortcomings such as lack of long-term follow-up and different frequency and duration of treatment. Therefore, future randomized controlled trials (RCTs) with larger sample sizes and longer-term observations are needed to verify the effectiveness of VRT in combination with anti-vertigo drugs for VN.Systematic Review Registration: https://www.crd.york.ac.uk/prospero/.

16.
Sci Rep ; 13(1): 16781, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37798447

RESUMO

High-efficiency rock breaking technology is an important problem to be solved urgently in deep mining. The existing auxiliary rock breaking technology for coal mine excavation has problems such as polluting coal, high requirements for tool materials, and difficulty in subsequent washing. In this paper, an active excitation cutting system for rotary cylinder of cantilever roadheader based on alternating valve is proposed. According to the classical calculation formula of cutting load of roadheader, considering the stiffness-damping characteristics of cutting part and cutting cylinder, the simulation algorithm of cutting load is compiled based on MATLAB simulation analysis software. The excitation cutting experiments of different cutting depths are carried out on the cutting test bench, and compared with the simulation algorithm of cutting load. Taking the cutting load as the discriminant index, the influence of oil supply pressure and excitation frequency of rotary cylinder on the cutting load is analyzed based on the simulation algorithm of cutting load. The results show that the error between the simulation results and the experimental results of the active excitation state is less than 12%, and the two are in good agreement. Under the condition of 30 HZ, when the excitation amplitude is 8 Mpa, 10 Mpa, 12 Mpa, 14 Mpa, when the rotary cylinder excitation amplitude is 10 Mpa, the minimum is 131.42 KN. Compared with the rotary cylinder excitation amplitude under the condition of 10 Mpa, when the excitation frequency is 30 HZ, 35 HZ, 40 HZ, 45 HZ, when the excitation frequency is 40 HZ, the minimum is 83.08 KN, indicating that changing the excitation amplitude or oil supply pressure of the rotary cylinder is helpful to adjust the cutting performance.

17.
Front Plant Sci ; 14: 1223720, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600181

RESUMO

Fritillaria unibracteata (FU) is a renowned herb in China that requires strict growth conditions in its cultivation process. During this process, the soil microorganisms and their metabolites may directly affect the growth and development of FU, for example, the pathogen infection and sipeimine production. However, few systematic studies have reported the changes in the microbiome and metabolites during FU cultivation thus far. In this work, we simultaneously used metagenomics and metabolomics technology to monitor the changes in microbial communities and metabolites in the rhizosphere of FU during its cultivation for one, two, and three years. Moreover, the interaction between microorganisms and metabolites was investigated by co-occurrence network analysis. The results showed that the microbial composition between the three cultivation-year groups was significantly different (2020-2022). The dominant genera changed from Pseudomonas and Botrytis in CC1 to Mycolicibacterium and Pseudogymnoascus in CC3. The relative abundances of beneficial microorganisms decreased, while the relative abundances of harmful microorganisms showed an increasing trend. The metabolomics results showed that significant changes of the of metabolite composition were observed in the rhizosphere soil, and the relative abundances of some beneficial metabolites showed a decreasing trend. In this study, we discussed the changes in the microbiome and metabolites during the three-year cultivation of FU and revealed the relationship between microorganisms and metabolites. This work provides a reference for the efficient and sustainable cultivation of FU.

18.
PLoS One ; 18(7): e0288753, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37478083

RESUMO

Underground roadway excavation is a complex process, especially roadway curved excavation. In addition, the rationality of the design of coal mine roadway excavation scheme directly affects the speed of roadway excavation. The more reasonable the scheme design, the more conducive to rapid excavation. In order to avoid the influence of invalid construction on the efficiency of roadway excavation, this paper studies the forming of roadway bend. Based on the analysis of the tunneling process of the roadway curve, the mathematical model of the roadway curve is established. Taking the turning radius of the roadway curve as the evaluation index, the influence of various factors on the roadway curve excavation is analyzed. The research shows that the radius of the roadway curve increases with the increase of the feed rate, the working space position of the roadheader and the required width of the roadway, and decreases with the increase of the working space angle. Then, combined with the advantages of KNN algorithm, an interpolation model for calculating the radius of the curve is established based on RBF algorithm, and the radius of the tunnel curve is reconstructed and predicted. It provides a basis for the rational design of the construction process of the roadway bend and a reliable numerical algorithm for the design of the radius of the roadway bend. It also provides a theoretical basis for improving the efficiency of high roadway excavation in coal mines.


Assuntos
Minas de Carvão , Modelos Teóricos , Carvão Mineral , Algoritmos
19.
Front Neurol ; 14: 1094617, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37139056

RESUMO

Background: The benefits of virtual reality (VR)-based rehabilitation were reported in patients after stroke, but there is insufficient evidence about how VR promotes brain activation in the central nervous system. Hence, we designed this study to explore the effects of VR-based intervention on upper extremity motor function and associated brain activation in stroke patients. Methods/design: In this single-center, randomized, parallel-group clinical trial with a blinded assessment of outcomes, a total of 78 stroke patients will be assigned randomly to either the VR group or the control group. All stroke patients who have upper extremity motor deficits will be tested with functional magnetic resonance imaging (fMRI), electroencephalography (EEG), and clinical evaluation. Clinical assessment and fMRI will be performed three times on each subject. The primary outcome is the change in performance on the Fugl-Meyer Assessment Upper Extremity Scale (FMA-UE). Secondary outcomes are functional independence measure (FIM), Barthel Index (BI), grip strength, and changes in the blood oxygenation level-dependent (BOLD) effect in the ipsilesional and contralesional primary motor cortex (M1) on the left and right hemispheres assessed with resting-state fMRI (rs-fMRI), task-state fMRI (ts-fMRI), and changes in EEG at the baseline and weeks 4 and 8. Discussion: This study aims to provide high-quality evidence for the relationship between upper extremity motor function and brain activation in stroke. In addition, this is the first multimodal neuroimaging study that explores the evidence for neuroplasticity and associated upper motor function recovery after VR in stroke patients. Clinical trial registration: Chinese Clinical Trial Registry, identifier: ChiCTR2200063425.

20.
Front Plant Sci ; 14: 1169317, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143880

RESUMO

Introduction: Atmospheric nitrogen (N) deposition has often been considered as a driver of exotic plant invasions. However, most related studies focused on the effects of soil N levels, and few on those of N forms, and few related studies were conducted in the fields. Methods: In this study, we grew Solanum rostratum, a notorious invader in arid/semi-arid and barren habitats, and two coexisting native plants Leymus chinensis and Agropyron cristatum in mono- and mixed cultures in the fields in Baicheng, northeast China, and investigated the effects of N levels and forms on the invasiveness of S. rostratum. Results: Compared with the two native plants, S. rostratum had higher aboveground and total biomass in both mono- and mixed monocultures under all N treatments, and higher competitive ability under almost all N treatments. N addition enhanced the growth and competitive advantage of the invader under most conditions, and facilitated invasion success of S. rostratum. The growth and competitive ability of the invader were higher under low nitrate relative to low ammonium treatment. The advantages of the invader were associated with its higher total leaf area and lower root to shoot ratio compared with the two native plants. The invader also had a higher light-saturated photosynthetic rate than the two native plants in mixed culture (not significant under high nitrate condition), but not in monoculture. Discussion: Our results indicated that N (especially nitrate) deposition may also promote invasion of exotic plants in arid/semi-arid and barren habitats, and the effects of N forms and interspecific competition need to be taken into consideration when studying the effects of N deposition on invasion of exotic plants.

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