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1.
Materials (Basel) ; 17(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38673104

RESUMO

This study investigates the dynamics of moisture absorption and swelling in soft rock during tunnel excavation, emphasizing the response to support resistance. Utilizing COMSOL numerical simulations, we conduct a comparative analysis of various strength criteria and non-associated flow rules. The results demonstrate that the Mohr-Coulomb criterion combined with the Drucker-Prager model under compressive loads imposes stricter limitations on water absorption and expansion than when paired with the Drucker-Prager model under tensile loads. Restricted rock expansion leads to decreased horizontal displacement and ground uplift, increased displacement in the tunnel's bottom arch, and significantly reduced displacement in the top arch. The study also considers the effects of shear dilation, burial depth, and support resistance on the stress and displacement of the surrounding rock. Increased shear dilation angles correlate with greater rock expansion, resulting in increased horizontal displacement and ground uplift. The research study concludes that support resistance is critical in limiting the movement of the tunnel's bottom arch and impacting the stability of the surrounding rock. Additionally, the extent of rock damage during the excavation of expansive soft rock tunnels is found to be minimal. Overall, this study provides valuable insights into the processes of soft rock tunnel excavation and contributes to the development of more efficient support systems.

2.
Mol Biol Rep ; 51(1): 309, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372835

RESUMO

OBJECTIVE: The aim of this study is to examine and evaluate the impact of benzene poisoning on the relative content of the mitochondrial MT-ND1 gene and telomere length in individuals with occupational chronic benzene poisoning (CBP) compared to a control group. The study will analyze and gather data on the mitochondrial gene content and telomere length in cases of benzene poisoning, and investigate the relationship with blood routine parameters in order to contribute scientific experimental data for the prevention and treatment of CBP. METHOD: The case group comprised 30 individuals diagnosed with occupational chronic benzene poisoning, whereas the control group consisted of 60 healthy individuals who underwent physical examinations at our hospital concurrently. Blood routine indicators were detected and analyzed, and the PCR method was employed to measure changes in mitochondrial MT-ND1 content and telomere length. Subsequently, a comparison and analysis of the aforementioned indicators was conducted. RESULT: The case group exhibited a higher mitochondrial gene content (median 366.2, IQR 90.0 rate) compared to the control group (median 101.5, IQR 12.0 rate), with a statistically significant difference between the two groups (P < 0.05). Additionally, the case group demonstrated lower white blood cell levels (3.78 ± 1.387 × 109/L) compared to the control group (5.74 ± 1.41 × 109/L), with a significant difference between the two groups (P < 0.05). Furthermore, the case group displayed lower red blood cell levels (3.86 ± 0.65 × 1012/L) compared to the control group (4.89 ± 0.65 × 1012/L), with a significant difference between the two groups (P < 0.05). The hemoglobin level in the case group (113.33 ± 16.34 g/L) was lower than that in the control group (138.22 ± 13.22 g/L). There was a significant difference between the two groups (P < 0.05). Platelet levels in the case group (153.80 ± 58.31 × 109/L) is smaller than the control group (244.92 ± 51.99 × 109/L), there was a significant difference between the two groups (P < 0.05). The average telomere length of the normal control group was 1.451 ± 0.475 (rate); The mean telomere length of individuals in the case group diagnosed with benzene poisoning was determined to be 1.237 ± 0.457 (rate). No significant correlation was observed between telomere length and three blood routine parameters, namely white blood cells (WBC), hemoglobin (HB), and platelets (PLT). However, a significant correlation was found between telomere length and red blood cell count (RBC). Additionally, a negative correlation was observed between mitochondrial gene content and white blood cell count (r = - 0.314, P = 0.026), as well as between mitochondrial gene content and red blood cell count (r = - 0.226, P = 0.032). Furthermore, a negative correlation was identified between mitochondrial gene content and hemoglobin (r = - 0.314, P = 0.028), and platelets (r = - 0.445, P = 0.001). CONCLUSION: Individuals diagnosed with occupational chronic benzene poisoning exhibit a reduction in telomere length and an elevation in the relative content of the mitochondrial MT-ND1 gene. Moreover, a negative correlation is observed between the content of the mitochondrial MT-ND1 gene and four blood routine parameters, namely white blood cells (WBC), red blood cells (RBC), hemoglobin (HB), and platelets (PLT). Consequently, benzene exposure may potentially contribute to the onset of premature aging.


Assuntos
Benzeno , DNA Mitocondrial , Humanos , DNA Mitocondrial/genética , Variações do Número de Cópias de DNA/genética , Leucócitos , Hemoglobinas , Telômero/genética
3.
Brain Imaging Behav ; 17(6): 652-663, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37673808

RESUMO

BACKGROUND: Previous neuroimaging research has examined static local brain activity changes in patients with anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis. However, the dynamic properties of local brain activity in anti-NMDAR encephalitis remain unknown. METHODS: This study used a combination of the amplitude of low-frequency fluctuation (ALFF) method and a sliding-window dynamic analysis approach to examine the time-varying local brain activity changes in anti-NMDAR encephalitis. RESULTS: Results showed that patients with anti-NMDAR encephalitis exhibited increased dynamic ALFF (dALFF) variability in the left inferior occipital gyrus compared to healthy controls (HCs), while the patients exhibited decreased sALFF in widespread regions, including the left inferior frontal gyrus, left medial frontal gyrus, bilateral putamen, left medial superior frontal gyrus. dALFF had superior classification performance in distinguishing anti-NMDAR encephalitis patients from HCs over sALFF, but sALFF was correlated with multiple clinical and neuropsychological measures. CONCLUSIONS: These findings may shed light on anti-NMDAR encephalitis brain dysfunction from the perspective of dynamic local brain activity. sALFF and dALFF analyses provide complementary information, emphasizing the potential usefulness of combining sALFF and dALFF in elucidating the neuropathological mechanisms of autoimmune encephalitis and may ultimately inform future disease diagnosis.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato , Encefalopatias , Doença de Hashimoto , Humanos , Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico por imagem , Imageamento por Ressonância Magnética , Receptores de N-Metil-D-Aspartato , Encéfalo/diagnóstico por imagem
4.
Materials (Basel) ; 16(14)2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37512185

RESUMO

After high-temperature treatment, both nano-titanium dioxide-modified concrete and ordinary concrete exhibit typical splitting failure. High-temperature heating reduces the mechanical properties and brittleness of concrete and improves the ductility of concrete. The stress-strain relationship of the specimens was obtained through the uniaxial compression test of ordinary concrete and nano-titanium dioxide-modified concrete cube specimens under normal temperature and high-temperature conditions. In addition, the relationship between temperature and damage variables was established, and the unified constitutive model containing damage variables after room temperature and high-temperature treatment of ordinary concrete and nano-titanium dioxide-modified concrete were established. It provides a reference for future research on the mechanical properties of high-performance concrete structures after high temperatures (fire).

5.
Neurosci Lett ; 800: 137123, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36780940

RESUMO

OBJECTIVE: To investigate large-scale internetwork functional connectivity in patients with vestibular migraine (VM) and migraine without aura (MwoA). METHODS: Resting-state functional magnetic resonance imaging data from 34 VM patients, 34 MwoA patients, and 33 healthy controls (HCs) were collected and the results were analyzed using independent component analysis (ICA). We also analyzed the correlations between clinical data and internetwork functional connectivity. RESULTS: In contrast to HCs, MwoA patients showed decreased functional connectivity between the left frontoparietal network (lFPN) and right frontoparietal network (rFPN), with increased functional connectivity between the sensorimotor network (SMN) and lateral visual network (lVN). When compared to MwoA patients, VM patients demonstrated decreased functional network connectivity between the dorsal attention network (DAN) and posterior medial visual network (pmVN), between the SMN and pmVN, and between the SMN and lVN. Meanwhile, increased functional network connectivity was found between the lFPN and rFPN; however, there was no significant difference in functional network connectivity between VM patients and HCs. In addition, associations were found between clinical data and internetwork functional connectivity. CONCLUSION: Functional connectivity between the lFPN and rFPN was reduced in patients with MwoA compared with HCs, which may indicate functional impairment in cognitive control, attention, somatosensory perception, and emotion regulation in patients with MwoA. VM patients showed decreased functional connectivity between the DAN, SMN, pmVN and lVN compared to patients with MwoA, which could account for the multisensory integration abnormalities and be the cause of vestibular symptoms in VM patients. These findings offer fresh perspectives on the pathophysiology of VM and MwoA.


Assuntos
Encéfalo , Enxaqueca sem Aura , Humanos , Imageamento por Ressonância Magnética/métodos , Estudos de Casos e Controles
6.
Front Neurosci ; 16: 928289, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35620670

RESUMO

[This corrects the article DOI: 10.3389/fnins.2021.677823.].

7.
Front Neurosci ; 15: 677823, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34177454

RESUMO

BACKGROUND: There is evidence that the T allele of rs405509 located in the apolipoprotein E (APOE) promotor region is a risk factor for Alzheimer's disease (AD). However, the effect of the T/T allele on brain function in non-demented aging is still unclear. METHODS: We analyzed the effects of the rs405509 T/T allele on cognitive performances using multiple neuropsychological tests and local brain function using resting-state functional magnetic resonance imaging (rs-fMRI). RESULTS: Significant differences were found between T/T carriers and G allele carriers on general cognitive status, memory, and attention (p < 0.05). Rs-fMRI analyses demonstrated decreased amplitude of low frequency fluctuation (ALFF) in the right middle frontal gyrus, decreased percent amplitude of fluctuation (PerAF) in the right middle frontal gyrus, increased regional homogeneity (ReHo) in the right cerebellar tonsil and decreased ReHo in the right putamen, and decreased degree centrality (DC) in the left middle frontal gyrus (p < 0.05, corrected). Furthermore, significant correlations were found between cognitive performance and these neuroimaging changes (p < 0.05). CONCLUSION: These findings suggest that T/T allele may serve as an independent risk factor that can influence brain function in different regions in non-demented aging.

8.
Sensors (Basel) ; 18(4)2018 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-29641505

RESUMO

There are many artificial parameters when fuse infrared and visible images, to overcome the lack of detail in the fusion image because of the artifacts, a novel fusion algorithm for infrared and visible images that is based on different constraints in non-subsampled shearlet transform (NSST) domain is proposed. There are high bands and low bands of images that are decomposed by the NSST. After analyzing the characters of the bands, fusing the high level bands by the gradient constraint, the fused image can obtain more details; fusing the low bands by the constraint of saliency in the images, the targets are more salient. Before the inverse NSST, the Nash equilibrium is used to update the coefficient. The fused images and the quantitative results demonstrate that our method is more effective in reserving details and highlighting the targets when compared with other state-of-the-art methods.

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