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2.
Clin Cancer Res ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652815

RESUMO

PURPOSE: This phase 1 trial aimed to determine the maximum tolerated fraction dose (MTFD) of hypofractionated radiotherapy (hypo-RT) combined with concurrent chemotherapy and subsequent consolidation immune checkpoint inhibitors (cICI) for patients with locally advanced non-small cell lung cancer (LA-NSCLC). PATIENTS AND METHODS: Split-course hypo-RT and hypo-boost combined with concurrent chemotherapy were administered at three dose levels (DLs), using a stepwise dose-escalation protocol. The sophisticated esophagus-sparing technique was implemented to restrict the dose to the esophagus. Patients who did not experience disease progression or unresolved G2+ toxicities after radiotherapy received cICI. Each DL aimed to treat 6 patients. The MTFD was defined as the highest DL at which <=2 patients of the 6 who were treated experienced treatment-related G3+ toxicity and <=1 patient experienced G4+ toxicity within 12 months post-radiotherapy. RESULTS: Eighteen patients were enrolled with 6 patients in each DL. All patients completed hypo-RT and concurrent chemotherapy, and 16 (88.9%) received at least one infusion of cICI, with a median of 10 infusions. Within the 12-month assessment period, one patient in DL1 experienced G3 pneumonitis, and one patient in DL3 developed G3 tracheobronchitis. The MTFD was not reached. The objective response rate (ORR) was 100%. With a median follow-up of 20.9 months, the 1-year overall survival and progression-free survival rate were 94.4% and 83.3%, respectively. CONCLUSIONS: Utilizing the split-course hypo-RT and hypo-boost approach, a fraction dose of 5Gy to a total dose of 60Gy, combined with concurrent chemotherapy and subsequent cICI, was well-tolerated, and yielded promising ORR and survival outcomes.

3.
J Gastrointest Surg ; 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38570232

RESUMO

BACKGROUND: Although preoperative neoadjuvant chemotherapy (NACT) or chemoradiation is the current standard of care for esophageal cancer in China, the impact of subsequent adjuvant therapy on patient prognosis remains unknown. This study aims to analyze the effect of adjuvant chemotherapy (ACT) on the survival rates of patients who have achieved a non-pathological complete response (non-pCR) after NACT and subsequent surgery. METHODS: We reviewed the data of 2193 patients with locally advanced thoracic esophageal squamous cell carcinoma (ESCC) who underwent radical surgery between January 2006 and January 2016. Of these patients, 46 received NACT and ACT, while 109 received NACT only. Propensity score matching was used to compare 86 patients, with 43 patients in the NACT + ACT group and 43 patients in the NACT group. Univariate analysis was performed using the Kaplan-Meier method and log-rank test, while Cox regression analysis was used for multivariate analysis. RESULTS: Multivariate analysis revealed that pathological lymph node status (positive vs negative) (P < .001) and treatment modalities (NACT + ACT vs NACT) (P = .005) were independent prognostic factors. There was a significant difference in long-term survival rates between the NACT + ACT and NACT groups, with 5-year survival rates of 55.8% vs 39.5%, respectively (c2 = 4.270, P = .039). In patients with ypN+ status, the 5-year survival rate was 31.8% for those who received ACT after NACT and surgery, compared to 10.0% for those who did not receive additional ACT (c2 = 6.101, P = .014). The corresponding percentages in patients with ypN- were 81.0% and 65.2%, respectively (c2 = 1.993, P = .158). CONCLUSION: Adjuvant chemotherapy should be recommended for locally advanced ESCC patients with residual cancer after NACT and surgery, especially for patients with nodal metastases after NACT.

4.
Front Neurosci ; 18: 1274651, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38586194

RESUMO

Purpose: To investigate the contrast sensitivity function (CSF) changes in simple high myopia (SHM) and evaluate the correlations between these changes with the early changes in the retinal microstructure. Methods: This prospective study comprised 81 subjects, 20 with emmetropia (EM), 26 with low myopia and moderate myopia (LM/MM), and 35 with SHM. The area under the log CSF curve (AULCSF) and the cut-off spatial frequency (Cut-off SF) were employed as measures of CSF. Adaptive optics (AO) was employed to quantify the cone density, spacing, and regularity. The thickness and blood flow of the retinal sublayers were determined from vertical and horizontal optical coherence tomography angiography (OCTA) A-scans. Swept-source optical coherence tomography (SS-OCT) was employed to analyze the choroidal thickness (CT) and choroidal vascularity using a custom algorithm. Differences in the retinal and choroidal parameters, cone distribution, AULCSF, and Cut-off SF were compared among the three groups. Multivariate linear mixed models were used to elucidate the associations between photoreceptor morphological alterations, retinal and choroidal parameters, and AULCSF. Results: The AULCSF and Cut-off SF were significantly lower in the SHM group compared to the EM and LM groups (p < 0.05). The SHM group had less cone density, larger cone spacing, and lower cone regularity than the EM and LM/MM groups (p < 0.05). Moreover, the thickness of the inner segment of photoreceptors (IS), retinal pigment epithelium (RPE) layer and choroid were reduced, and the outer segment of photoreceptors (OS) was thicker in the SHM group compared to the EM and LM/MM groups (all p < 0.05). A longer axial length (AL) was correlated with decreased AULCSF, cone density, and cone spacing (r = -0.800 to 0.752, all p < 0.050). Additionally, decreased CSF was correlated with lower cone density (r = 0.338, p = 0.035). Conclusion: Decreased contrast sensitivity was observed in patients with SHM and cone density was significantly correlated with reduced AUCSF.

5.
Neural Netw ; 176: 106328, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38688067

RESUMO

Given a graph G, the network collapse problem (NCP) selects a vertex subset S of minimum cardinality from G such that the difference in the values of a given measure function f(G)-f(G∖S) is greater than a predefined collapse threshold. Many graph analytic applications can be formulated as NCPs with different measure functions, which often pose a significant challenge due to their NP-hard nature. As a result, traditional greedy algorithms, which select the vertex with the highest reward at each step, may not effectively find the optimal solution. In addition, existing learning-based algorithms do not have the ability to model the sequence of actions taken during the decision-making process, making it difficult to capture the combinatorial effect of selected vertices on the final solution. This limits the performance of learning-based approaches in non-submodular NCPs. To address these limitations, we propose a unified framework called DT-NC, which adapts the Decision Transformer to the Network Collapse problems. DT-NC takes into account the historical actions taken during the decision-making process and effectively captures the combinatorial effect of selected vertices. The ability of DT-NC to model the dependency among selected vertices allows it to address the difficulties caused by the non-submodular property of measure functions in some NCPs effectively. Through extensive experiments on various NCPs and graphs of different sizes, we demonstrate that DT-NC outperforms the state-of-the-art methods and exhibits excellent transferability and generalizability.

6.
J Comput Biol ; 31(3): 213-228, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38531049

RESUMO

Molecular prediction tasks normally demand a series of professional experiments to label the target molecule, which suffers from the limited labeled data problem. One of the semisupervised learning paradigms, known as self-training, utilizes both labeled and unlabeled data. Specifically, a teacher model is trained using labeled data and produces pseudo labels for unlabeled data. These labeled and pseudo-labeled data are then jointly used to train a student model. However, the pseudo labels generated from the teacher model are generally not sufficiently accurate. Thus, we propose a robust self-training strategy by exploring robust loss function to handle such noisy labels in two paradigms, that is, generic and adaptive. We have conducted experiments on three molecular biology prediction tasks with four backbone models to gradually evaluate the performance of the proposed robust self-training strategy. The results demonstrate that the proposed method enhances prediction performance across all tasks, notably within molecular regression tasks, where there has been an average enhancement of 41.5%. Furthermore, the visualization analysis confirms the superiority of our method. Our proposed robust self-training is a simple yet effective strategy that efficiently improves molecular biology prediction performance. It tackles the labeled data insufficient issue in molecular biology by taking advantage of both labeled and unlabeled data. Moreover, it can be easily embedded with any prediction task, which serves as a universal approach for the bioinformatics community.


Assuntos
Biologia Computacional , Biologia Molecular , Humanos , Aprendizado de Máquina Supervisionado
7.
Clin Chim Acta ; 557: 117854, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38513931

RESUMO

Intrahepatic cholestasis of pregnancy (ICP) is associated with an increased risk of cesarean section and adverse fetal outcomes. Currently, ICP diagnosis depends largely on serum levels of bile acids and lacks sensitivity and specificity for accurate diagnosis. Tongue diagnosis is an important diagnostic tool in traditional Chinese medicine (TCM) and is used in our clinic as complementary treatment and personalized medicine for ICP. However, the molecular basis of the manifestation of greasy white tongue coatings in ICP remains unknown. In this study, we performed untargeted metabolomic profiling of the serum, tongue coating, and saliva of 66 pregnant women, including 22 with ICP. The metabolomic profiles of the serum and tongue coatings showed marked differences between the two clinical groups. Forty-six differentially abundant metabolites were identified, and their relative concentrations correlated with total bile acid levels. These differential metabolites included bile acids, lipids, microbiota- and diet-related metabolites, and exposomes. Conventional biochemical markers, including serum aminotransferases and bilirubin, were not significantly increased in the ICP group, whereas the total cholesterol and triglyceride levels were significantly increased as early as the first trimester. Our data provide insights into the pathophysiology of ICP and implicate the gut-liver axis and environmental exposure. Tongue coating has the potential to be a non-invasive diagnostic approach. Further studies are required to validate the clinical utility of these findings.


Assuntos
Colestase Intra-Hepática , Complicações na Gravidez , Gravidez , Feminino , Humanos , Gestantes , Cesárea , Ácidos e Sais Biliares , Complicações na Gravidez/diagnóstico , Colestase Intra-Hepática/diagnóstico , Língua
8.
Clin Exp Optom ; : 1-7, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38484726

RESUMO

CLINICAL RELEVANCE: It is particularly important to perform reasonable and effective optical correction to enable visual development after primary lens removal surgery for congenital cataracts. Aphakic infants need a suitable addition power of prescription (ADD) to help them focus on close visual objects. BACKGROUND: It is challenging to obtain appropriate ADD power for infants due to poor cooperation and lack of subjective feedback. We aimed to determine the appropriate ADD for aphakic infants using a recently developed smart wearable device called Clouclip. METHODS: The study was a cross-sectional, observational pilot study. Twenty-three aphakic infants (aged from 6 months to 3.5 years) were invited to wear a smart wearable device for 7 days consecutively to monitor the near viewing distance in real life. Viewing habits and its associations with the possible influencing factors were investigated based on the data obtained from the device. RESULTS: The average proportion of near viewing time was 77.9% (95% confidence interval (CI) 72.1-83.7%). The average of the median near viewing distance was 23.8 cm (95% CI 20.6 cm-27.0 cm), which corresponded to an ADD of +4.25 D (95% CI + 3.75 D - +4.75 D) spectacle prescription. The height of the child was found to be positively correlated with the median of near viewing distance (r = 0.646, p = 0.001). Age, current ADD, age of cataract extraction surgery and bilaterality or monocularity of the aphakic eyes showed no significant correlation with the aforementioned viewing habits (all p > 0.05). CONCLUSION: By using the novel wearable device, we found the suitable ADD of spectacle prescription for aphakic infants is about +4.25 D. The height of the child was an influencing factor for ADD.

9.
Nat Methods ; 21(4): 623-634, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38504113

RESUMO

Single-cell proteomics sequencing technology sheds light on protein-protein interactions, posttranslational modifications and proteoform dynamics in the cell. However, the uncertainty estimation for peptide quantification, data missingness, batch effects and high noise hinder the analysis of single-cell proteomic data. It is important to solve this set of tangled problems together, but the existing methods tailored for single-cell transcriptomes cannot fully address this task. Here we propose a versatile framework designed for single-cell proteomics data analysis called scPROTEIN, which consists of peptide uncertainty estimation based on a multitask heteroscedastic regression model and cell embedding generation based on graph contrastive learning. scPROTEIN can estimate the uncertainty of peptide quantification, denoise protein data, remove batch effects and encode single-cell proteomic-specific embeddings in a unified framework. We demonstrate that scPROTEIN is efficient for cell clustering, batch correction, cell type annotation, clinical analysis and spatially resolved proteomic data exploration.


Assuntos
Aprendizagem , Proteômica , Análise por Conglomerados , Processamento de Proteína Pós-Traducional , Peptídeos
10.
Sci Adv ; 10(8): eadl2238, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394209

RESUMO

Skeletal stem cells (SSCs) that are capable of self-renewal and multipotent differentiation contribute to bone development and homeostasis. Several populations of SSCs at different skeletal sites have been reported. Here, we identify a metaphyseal SSC (mpSSC) population whose transcriptional landscape is distinct from other bone mesenchymal stromal cells (BMSCs). These mpSSCs are marked by Sstr2 or Pdgfrb+Kitl-, located just underneath the growth plate, and exclusively derived from hypertrophic chondrocytes (HCs). These HC-derived mpSSCs have properties of self-renewal and multipotency in vitro and in vivo, producing most HC offspring postnatally. HC-specific deletion of Hgs, a component of the endosomal sorting complex required for transport, impairs the HC-to-mpSSC conversion and compromises trabecular bone formation. Thus, mpSSC is the major source of BMSCs and osteoblasts in bone marrow, supporting the postnatal trabecular bone formation.


Assuntos
Osso Esponjoso , Células-Tronco Mesenquimais , Células-Tronco , Osso e Ossos , Diferenciação Celular , Osteoblastos , Osteogênese/genética
11.
Sci Total Environ ; 924: 171287, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38423316

RESUMO

It remains challenging to establish reliable links between transformation products (TPs) of contaminants and corresponding microbes. This challenge arises due to the sophisticated experimental regime required for TP discovery and the compositional nature of 16S rRNA gene amplicon sequencing and mass spectrometry datasets, which can potentially confound statistical inference. In this study, we present a new strategy by combining the use of 2H-labeled Stable Isotope-Assisted Metabolomics (2H-SIAM) with a neural network-based algorithm (i.e., MMvec) to explore links between TPs of pyrene and the soil microbiome. The links established by this novel strategy were further validated using different approaches. Briefly, a metagenomic study provided indirect evidence for the established links, while the identification of pyrene degraders from soils, and a DNA-based stable isotope probing (DNA-SIP) study offered direct evidence. The comparison among different approaches, including Pearson's and Spearman's correlations, further confirmed the superior performance of our strategy. In conclusion, we summarize the unique features of the combined use of 2H-SIAM and MMvec. This study not only addresses the challenges in linking TPs to microbes but also introduces an innovative and effective approach for such investigations. Environmental Implication: Taxonomically diverse bacteria performing successive metabolic steps of the contaminant were firstly depicted in the environmental matrix.


Assuntos
Microbiota , Solo , Solo/química , RNA Ribossômico 16S , Isótopos/análise , DNA , Pirenos , Redes Neurais de Computação , Microbiologia do Solo
12.
Front Immunol ; 15: 1332492, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38375480

RESUMO

Purpose: The need for adjuvant therapy (AT) following neoadjuvant chemoimmunotherapy (nICT) and surgery in esophageal squamous cell cancer (ESCC) remains uncertain. This study aims to investigate whether AT offers additional benefits in terms of recurrence-free survival (RFS) for ESCC patients after nICT and surgery. Methods: Retrospective analysis was conducted between January 2019 and December 2022 from three centers. Eligible patients were divided into two groups: the AT group and the non-AT group. Survival analyses comparing different modalities of AT (including adjuvant chemotherapy and adjuvant chemoimmunotherapy) with non-AT were performed. The primary endpoint was RFS. Propensity score matching(PSM) was used to mitigate inter-group patient heterogeneity. Kaplan-Meier survival curves and Cox regression analysis were employed for recurrence-free survival analysis. Results: A total of 155 nICT patients were included, with 26 patients experiencing recurrence. According to Cox analysis, receipt of adjuvant therapy emerged as an independent risk factor(HR:2.621, 95%CI:[1.089,6.310], P=0.032), and there was statistically significant difference in the Kaplan-Meier survival curves between non-AT and receipt of AT in matched pairs (p=0.026). Stratified analysis revealed AT bring no survival benefit to patients with pathological complete response(p= 0.149) and residual tumor cell(p=0.062). Subgroup analysis showed no significant difference in recurrence-free survival between non-AT and adjuvant chemoimmunotherapy patients(P=0.108). However, patients receiving adjuvant chemotherapy exhibited poorer recurrence survival compared to non-AT patients (p= 0.016). Conclusion: In terms of recurrence-free survival for ESCC patients after nICT and surgery, the necessity of adjuvant therapy especially the adjuvant chemotherapy, can be mitigated.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/terapia , Terapia Neoadjuvante , Neoplasias Esofágicas/patologia , Estudos Retrospectivos , Pontuação de Propensão , Intervalo Livre de Doença
13.
ACS Omega ; 9(5): 5378-5385, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38343912

RESUMO

In this work, sodium chlorite method was used to remove lignin in basswood and then the wood was dyed with reactive red X-3B dye. Finally, ultraviolet curing resins with a refractive index similar to cellulose were vacuum-impregnated into the wood to obtain red transparent wood (RTW). Nowadays, transparent wood can be given color by various means and has a wide range of application prospects in the field of transparent wood decoration, but the color embodiment is relatively single. The aim was to develop a low-priced, easy-to-use process for the preparation of colored transparent wood with a sound color system. Transparent wood with colors will have more decorative and commercial value. The chemical composition, microscopic morphology, mechanical properties, and optical properties of dyed transparent wood were examined and analyzed. The results of the chemical composition analysis showed that after delignified treatment, the wood lost a large amount of lignin. After the dyeing treatment, the content of cellulose, hemicellulose, and lignin was slightly lost, and reactive dye groups appeared in the wood. Infrared spectra of transparent samples showed that the resin was successfully impregnated into the wood. The microscopic morphology analysis results showed that a small amount of dye molecules aggregated on the cell walls after dyeing treatment, and the resin was impregnated into the porous cellulose skeleton of the wood, filling the wood pores. The analysis of mechanical properties showed that the maximum tensile strength of dyed transparent wood reached 122.31 MPa, which was a higher resistance to tensile force compared to raw wood (with a maximum tensile strength of 97.56 MPa); the elongation at break reached 6.26%, which had better toughness compared to log (4.04%). Optical performance analysis showed that the transmittance of dyed transparent wood reached 81%, and dyeing did not change the transmittance of transparent wood. In addition, after undergoing yellowing resistance experiments, the color difference change of dyed transparent wood was much smaller than that of transparent wood.

14.
Transl Neurodegener ; 13(1): 3, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191451

RESUMO

BACKGROUND: Microglia-mediated neuroinflammation in Alzheimer's disease (AD) is not only a response to pathophysiological events, but also plays a causative role in neurodegeneration. Cytoplasmic cysteinyl-tRNA synthetase (CARS) is considered to be a stimulant for immune responses to diseases; however, it remains unknown whether CARS is involved in the pathogenesis of AD. METHODS: Postmortem human temporal cortical tissues at different Braak stages and AD patient-derived serum samples were used to investigate the changes of CARS levels in AD by immunocytochemical staining, real-time PCR, western blotting and ELISA. After that, C57BL/6J and APP/PS1 transgenic mice and BV-2 cell line were used to explore the role of CARS protein in memory and neuroinflammation, as well as the underlying mechanisms. Finally, the associations of morphological features among CARS protein, microglia and dense-core plaques were examined by immunocytochemical staining. RESULTS: A positive correlation was found between aging and the intensity of CARS immunoreactivity in the temporal cortex. Both protein and mRNA levels of CARS were increased in the temporal cortex of AD patients. Immunocytochemical staining revealed increased CARS immunoreactivity in neurons of the temporal cortex in AD patients. Moreover, overexpression of CARS in hippocampal neurons induced and aggravated cognitive dysfunction in C57BL/6J and APP/PS1 mice, respectively, accompanied by activation of microglia and the TLR2/MyD88 signaling pathway as well as upregulation of proinflammatory cytokines. In vitro experiments showed that CARS treatment facilitated the production of proinflammatory cytokines and the activation of the TLR2/MyD88 signaling pathway of BV-2 cells. The accumulation of CARS protein occurred within dense-core Aß plaques accompanied by recruitment of ameboid microglia. Significant upregulation of TLR2/MyD88 proteins was also observed in the temporal cortex of AD. CONCLUSIONS: The findings suggest that the neuronal CARS drives neuroinflammation and induces memory deficits, which might be involved in the pathogenesis of AD.


Assuntos
Doença de Alzheimer , Humanos , Animais , Camundongos , Camundongos Endogâmicos C57BL , Doença de Alzheimer/complicações , Doença de Alzheimer/genética , Fator 88 de Diferenciação Mieloide , Doenças Neuroinflamatórias , Receptor 2 Toll-Like , Proteínas Adaptadoras de Transdução de Sinal , Citocinas
15.
Phytomedicine ; 124: 155288, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38183698

RESUMO

BACKGROUND: The scarcity of drugs targeting AML cells poses a significant challenge in AML management. Z-Ligustilide (Z-LIG), a phthalide compound, shows promising pharmacological potential as a candidate for AML therapy. However, its precise selective mechanism remains unclear. PURPOSE: In order to assess the selective inducement effects of Z-LIG on ferroptosis in AML cells and explore the possible involvement of the Nrf2/HO-1 pathway in the regulation of ferroptosis. METHODS: Through in vitro cell proliferation and in vivo tumor growth tests, the evaluation of Z-LIG's anticancer activity was conducted. Ferroptosis was determined by the measurement of ROS and lipid peroxide levels using flow cytometry, as well as the observation of mitochondrial morphology. To analyze the iron-related factors, western blot analysis was employed. The up-regulation of the Nrf2/HO-1 axis was confirmed through various experimental techniques, including CRISPR/Cas9 gene knockout, fluorescent probe staining, and flow cytometry. The efficacy of Z-LIG in inducing ferroptosis was further validated in a xenograft nude mouse model. RESULTS: Our study revealed that Z-LIG specifically triggered lipid peroxidation-driven cell death in AML cells. Z-LIG downregulated the total protein and nuclear entrance levels of IRP2, resulting in upregulation of FTH1 and downregulation of TFR1. Z-LIG significantly increased the susceptibility to ferroptosis by upregulating ACSL4 levels and simultaneously suppressing the activity of GPX4. Notably, the Nrf2/HO-1 pathway displayed a twofold impact in the ferroptosis induced by Z-LIG. Mild activation suppressed ferroptosis, while excessive activation promoted it, mainly driven by ROS-induced labile iron pool (LIP) accumulation in AML cells, which was not observed in normal human cells. Additionally, Nrf2 knockout and HO-1 knockdown reversed iron imbalance and mitochondrial damage induced by Z-LIG in HL-60 cells. Z-LIG effectively inhibited the growth of AML xenografts in mice, and Nrf2 knockout partially weakened its antitumor effect by inhibiting ferroptosis. CONCLUSION: Our study presents biological proof indicating that the selective initiation of ferroptosis in leukemia cells is credited to the excessive activation of the Nrf2/HO-1 pathway triggered by Z-LIG.


Assuntos
4-Butirolactona/análogos & derivados , Ferroptose , Leucemia Mieloide Aguda , Humanos , Camundongos , Animais , Espécies Reativas de Oxigênio/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Leucemia Mieloide Aguda/metabolismo , Ferro/metabolismo
16.
ACS Omega ; 9(1): 866-878, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38222645

RESUMO

In order to clarify the movement characteristics of dust particles in the intake tunnel and improve the underground intake tunnel environment, the main intake tunnel of Wulihou Coal Mine was taken as the engineering background, the COMSOL simulation software was adopted to establish a model, the influence of air volume and temperature on dust movement characteristics was studied, and the critical air volume and particle size of dust at room temperature were determined. The results show that with the ventilation air volume being the same, when the dust reaches the exit of the tunnel, its falling height is positively correlated with the particle size. When the dust particle size is the same, the height of the dust falling is negatively correlated with the ventilation air volume. As the particle size of dust increases, the impact of changes in air volume on its movement decreases and the trajectory of dust movement gradually becomes consistent. The height of dust falling is negatively correlated with the air flow temperature. Therefore, when other factors remain unchanged, dust pollution in the tunnel is relatively severe during the day and the dust concentration in the tunnel is higher in summer. The critical air volume for dust emission in the intake tunnel of Wulihou Coal Mine is 75.84 m3/s, corresponding to a central wind speed of 5.29 m/s in the tunnel. The critical particle size for dust emission is 1.4 µm.

17.
Med Biol Eng Comput ; 62(3): 883-899, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38081953

RESUMO

Rehabilitation robots are used to promote structural and functional recovery of the nervous system with repetitive, task-oriented training and have been gradually applied to clinical rehabilitation training. This paper proposes an upper limb exoskeleton rehabilitation robot system that could realize shoulder-elbow-wrist joint rehabilitation training. Firstly, a motion equivalent model was established based on the upper limb movement mechanism, the robot mechanism configuration was designed, and the optimization algorithm and spatial mechanism theory were used to optimize and analyze the structural parameters and human-machine compatibility of the robot, which will guide the design of the robot's model. Then, the robot kinematics were solved, and its maximum motion range, dexterity distribution, and daily motion trajectory were simulated. Finally, a system prototype was built to test the maximum range of robot-assisted human upper limb training by laser tracker, while the pressure of human-machine interaction during training was captured and analyzed by flexible sensors. The results show that the proposed rehabilitation robot could nearly completely cover the range of motion of upper limb joints and meet the needs of trajectory training, and the linear velocity dexterity and angular velocity dexterity in the motion space are maximum 0.55 and 0.89, and the human-machine interaction pressures during the training process are all less than 10 kPa. Besides, this paper also conducted a system evaluation based on the fuzzy comprehensive evaluation model, and the evaluation result was 0.39, with an excellent evaluation grade, it indirectly indicates that the robot's overall performance was good.


Assuntos
Exoesqueleto Energizado , Robótica , Articulação do Ombro , Humanos , Robótica/métodos , Extremidade Superior/fisiologia , Movimento/fisiologia
18.
IEEE Trans Biomed Eng ; 71(3): 772-779, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37768791

RESUMO

In this article, we introduce a novel use of depth camera to extract cardiac pulse signal from human chest area, in which the depth information is obtained from a near infrared sensor using time-of-flight technology. We successfully isolate weak chest motion due to heartbeat by processing a sequence of depth images without raising privacy concern. We discuss motion sensitivity in depth video with examples from actuator simulation and human chest motion. Compared to other imaging modalities, the depth image intensity can be directly used for micromotion reconstruction. To deal with the challenges of recovering heartbeat from the chest area, we develop a set of coherent processing techniques to suppress the unwanted motion interference from breathing motion and involuntary body motion and eventually obtain clean cardiac pulse signal. We, thus, derive inter-beat-interval, showing high consistency to the contact photoplethysmography. Additionally, we develop a graphical interpretation of the most and the less pulsatile principal components in eigen space. For validation, we test our method on ten healthy human subjects with different resting heart rates. More importantly, we conduct a set of experiments to study the robustness and weakness of our methods, including extended range, multi-subject, thickness of clothes and generation to other measurement site.


Assuntos
Algoritmos , Coração , Humanos , Frequência Cardíaca/fisiologia , Coração/diagnóstico por imagem , Coração/fisiologia , Respiração , Tórax/diagnóstico por imagem , Movimento (Física) , Fotopletismografia/métodos , Processamento de Sinais Assistido por Computador
19.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1006270

RESUMO

ObjectiveTo study the mechanism of astragaloside Ⅳ (AS Ⅳ) on db/db mice with type 2 diabetes mellitus (T2DM) and non-alcoholic fatty liver disease (NAFLD) based on network pharmacology and experimental validation. MethodA total of 24 db/db mice were randomly divided into four groups: model group, metformin group, and low-dose and high-dose AS Ⅳ groups. Six C57 mice were used as the blank group. The low-dose and high-dose AS Ⅳ groups were given AS Ⅳ of 0.015 and 0.030 g·kg-1 by gavage, and the metformin group was given 0.067 g·kg-1 by gavage. The blank and model groups were given equal volumes of distilled water by gavage. After intragastric administration, fasting blood glucose (FBG) was detected, and an oral glucose tolerance test was performed. Serum lipid level and liver histopathology were detected. The target and enrichment pathway of AS Ⅳ for treating T2DM and NAFLD were predicted by network pharmacology, and the main enrichment pathway was verified by molecular biology techniques. The protein expressions of AMPK, p-AMPK, sterol regulatory element-binding protein-1 (SREBP-1), and fatty acid synthetase (FAS) in liver tissue were detected by Western blot. ResultCompared with the blank group, the levels of body mass, liver weight coefficient, fasting blood glucose, serum total cholesterol, triglyceride, and low-density lipoprotein cholesterol in mice treated with AS Ⅳ were decreased (P<0.05, P<0.01). The pathology of liver tissue showed significant improvement in lipid accumulation, and imaging results showed that the degree of fatty liver was reduced after AS Ⅳ therapy. Network pharmacological prediction results showed that vascular endothelial growth factor α (VEGFA), galactoagglutinin 3 (LGALS3), serine/threonine kinase B2 (Akt2), RHO-associated coiled-coil protein kinase 1 (ROCK1), serine/threonine kinase B1 (Akt1), signaling and transcriptional activator protein (STAT3), and messtimal epidermal transformation factor (MET) were key targets in "drug-disease" network. The results from the Kyoto encyclopedia of genes and genomes (KEGG) enrichment showed that the AMP-dependent protein kinase (AMPK) signaling pathway was strongly associated with T2DM and NAFLD. Western blot results showed that compared with the blank group, the expression levels of p-AMPK/AMPK in the model group were significantly down-regulated, while those of SREBP-1 and FAS proteins were significantly up-regulated (P<0.01). Compared with the model group, the expression levels of p-AMPK/AMPK in the metformin group and high-dose AS Ⅳ group were significantly up-regulated, while those of SREBP-1 and FAS proteins were significantly down-regulated (P<0.05, P<0.01). ConclusionAS Ⅳ regulates the expression of lipid proteins by activating the AMPK signaling pathway, thereby improving lipid metabolism.

20.
Nat Commun ; 14(1): 8032, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052823

RESUMO

Unsorted retired batteries with varied cathode materials hinder the adoption of direct recycling due to their cathode-specific nature. The surge in retired batteries necessitates precise sorting for effective direct recycling, but challenges arise from varying operational histories, diverse manufacturers, and data privacy concerns of recycling collaborators (data owners). Here we show, from a unique dataset of 130 lithium-ion batteries spanning 5 cathode materials and 7 manufacturers, a federated machine learning approach can classify these retired batteries without relying on past operational data, safeguarding the data privacy of recycling collaborators. By utilizing the features extracted from the end-of-life charge-discharge cycle, our model exhibits 1% and 3% cathode sorting errors under homogeneous and heterogeneous battery recycling settings respectively, attributed to our innovative Wasserstein-distance voting strategy. Economically, the proposed method underscores the value of precise battery sorting for a prosperous and sustainable recycling industry. This study heralds a new paradigm of using privacy-sensitive data from diverse sources, facilitating collaborative and privacy-respecting decision-making for distributed systems.

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