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1.
J Integr Neurosci ; 23(7): 141, 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39082286

ABSTRACT

BACKGROUND: Hypoxic-ischemic injury of neurons is a pathological process observed in several neurological conditions, including ischemic stroke and neonatal hypoxic-ischemic brain injury (HIBI). An optimal treatment strategy for these conditions remains elusive. The present study delved deeper into the molecular alterations occurring during the injury process in order to identify potential therapeutic targets. METHODS: Oxygen-glucose deprivation/reperfusion (OGD/R) serves as an established in vitro model for the simulation of HIBI. This study utilized RNA sequencing to analyze rat primary hippocampal neurons that were subjected to either 0.5 or 2 h of OGD, followed by 0, 9, or 18 h of reperfusion. Differential expression analysis was conducted to identify genes dysregulated during OGD/R. Time-series analysis was used to identify genes exhibiting similar expression patterns over time. Additionally, functional enrichment analysis was conducted to explore their biological functions, and protein-protein interaction (PPI) network analyses were performed to identify hub genes. Quantitative real-time polymerase chain reaction (qRT-PCR) was used for validation of hub-gene expression. RESULTS: The study included a total of 24 samples. Analysis revealed distinct transcriptomic alterations after OGD/R processes, with significant dysregulation of genes such as Txnip, Btg2, Egr1 and Egr2. In the OGD process, 76 genes, in two identified clusters, showed a consistent increase in expression; functional analysis showed involvement of inflammatory responses and signaling pathways like tumor necrosis factor (TNF), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and interleukin 17 (IL-17). PPI network analysis suggested that Ccl2, Jun, Cxcl1, Ptprc, and Atf3 were potential hub genes. In the reperfusion process, 274 genes, in three clusters, showed initial upregulation followed by downregulation; functional analysis suggested association with apoptotic processes and neuronal death regulation. PPI network analysis identified Esr1, Igf-1, Edn1, Hmox1, Serpine1, and Spp1 as key hub genes. qRT-PCR validated these trends. CONCLUSIONS: The present study provides a comprehensive transcriptomic profile of an in vitro OGD/R process. Key hub genes and pathways were identified, offering potential targets for neuroprotection after hypoxic ischemia.


Subject(s)
Hypoxia-Ischemia, Brain , Neurons , Transcriptome , Animals , Hypoxia-Ischemia, Brain/metabolism , Hypoxia-Ischemia, Brain/genetics , Rats , Neurons/metabolism , Hippocampus/metabolism , Rats, Sprague-Dawley , Glucose/metabolism , Cells, Cultured , Disease Models, Animal , Protein Interaction Maps
2.
Front Immunol ; 15: 1412693, 2024.
Article in English | MEDLINE | ID: mdl-39076970

ABSTRACT

Background: Esophageal cancer (ESCA) is one of the most common tumors in the world, and treatment using neoadjuvant therapy (NT) based on radiotherapy and/or chemotherapy has still unsatisfactory results. Neoadjuvant immunochemotherapy (NICT) has also become an effective treatment strategy nowadays. However, its impact on the tumor microenvironment (TME) and regulatory mechanisms on T cells and NK cells needs to be further elucidated. Methods: A total of 279 cases of ESCA who underwent surgery alone [non-neoadjuvant therapy (NONE)], neoadjuvant chemotherapy (NCT), and NICT were collected, and their therapeutic effect and survival period were compared. Further, RNA sequencing combined with biological information was used to analyze the expression of immune-related genes. Immunohistochemistry, immunofluorescence, and quantitative real-time PCR (qRT-PCR) were used to verify the activation and infiltration status of CD8+ T and CD16+ NK cells, as well as the function and regulatory pathway of killing tumor cells. Results: Patients with ESCA in the NICT group showed better clinical response, median survival, and 2-year survival rates (p < 0.05) compared with the NCT group. Our RNA sequencing data revealed that NICT could promote the expression of immune-related genes. The infiltration and activation of immune cells centered with CD8+ T cells were significantly enhanced. CD8+ T cells activated by PD-1 inhibitors secreted more IFN-γ and cytotoxic effector factor cells through the transcription factor of EOMES and TBX21. At the same time, activated CD8+ T cells mediated the CD16+ NK cell activation and secreted more IFN-γ to kill ESCA cells. In addition, the immunofluorescence co-staining results showed that more CD276+ tumor cells and CD16+ NK cells were existed in pre-NCT and pre-NICT group. However, CD276+ tumor cells were reduced significantly in the post-NICT group, while they still appeared in the post-NCT group, which means that CD16+ NK cells can recognize and kill CD276+ tumor cells after immune checkpoint blocker (ICB) treatment. Conclusion: NICT can improve the therapeutic effect and survival period of resectable ESCA patients. NICT could promote the expression of immune-related genes and activate CD8+ T and CD16+ NK cells to secrete more IFN-γ to kill ESCA cells. It provides a theoretical basis and clinical evidence for its potential as an NT strategy in ESCA.


Subject(s)
CD8-Positive T-Lymphocytes , Esophageal Neoplasms , Killer Cells, Natural , Neoadjuvant Therapy , Receptors, IgG , Tumor Microenvironment , Humans , Esophageal Neoplasms/therapy , Esophageal Neoplasms/immunology , Esophageal Neoplasms/mortality , Killer Cells, Natural/immunology , Killer Cells, Natural/metabolism , Neoadjuvant Therapy/methods , Male , Female , Receptors, IgG/metabolism , Receptors, IgG/genetics , CD8-Positive T-Lymphocytes/immunology , Middle Aged , Tumor Microenvironment/immunology , Aged , GPI-Linked Proteins/metabolism , Treatment Outcome , Immunotherapy/methods , Adult , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/metabolism
3.
Article in English | MEDLINE | ID: mdl-38952341

ABSTRACT

Immune checkpoint inhibitors (ICIs) targeting programmed cell death 1/programmed cell death ligand-1 (PD-1/PD-L1) have significantly prolonged the survival of advanced/metastatic patients with lung cancer. However, only a small proportion of patients can benefit from ICIs, and clinical management of the treatment process remains challenging. Glycosylation has added a new dimension to advance our understanding of tumor immunity and immunotherapy. To systematically characterize anti-PD-1/PD-L1 immunotherapy-related changes in serum glycoproteins, a series of serum samples from 12 patients with metastatic lung squamous cell carcinoma (SCC) and lung adenocarcinoma (ADC), collected before and during ICIs treatment, are firstly analyzed with mass-spectrometry-based label-free quantification method. Second, a stratification analysis is performed among anti-PD-1/PD-L1 responders and non-responders, with serum levels of glycopeptides correlated with treatment response. In addition, in an independent validation cohort, a large-scale site-specific profiling strategy based on chemical labeling is employed to confirm the unusual characteristics of IgG N-glycosylation associated with anti-PD-1/PD-L1 treatment. Unbiased label-free quantitative glycoproteomics reveals serum levels' alterations related to anti-PD-1/PD-L1 treatment in 27 out of 337 quantified glycopeptides. The intact glycopeptide EEQFN 177STYR (H3N4) corresponding to IgG4 is significantly increased during anti-PD-1/PD-L1 treatment (FC=2.65, P=0.0083) and has the highest increase in anti-PD-1/PD-L1 responders (FC=5.84, P=0.0190). Quantitative glycoproteomics based on protein purification and chemical labeling confirms this observation. Furthermore, obvious associations between the two intact glycopeptides (EEQFN 177STYR (H3N4) of IgG4, EEQYN 227STFR (H3N4F1) of IgG3) and response to treatment are observed, which may play a guiding role in cancer immunotherapy. Our findings could benefit future clinical disease management.

4.
J Cell Biochem ; : e30629, 2024 Jul 14.
Article in English | MEDLINE | ID: mdl-39004898

ABSTRACT

The current treatment of skin fibrosis is limited in its effectiveness due to a lack of understanding of the underlying mechanisms. Previous research has shown a connection between microRNAs (miRNAs) and the development of skin fibrosis. Therefore, investigating miRNA for the treatment of skin fibrotic diseases is highly important and merits further exploration. In this study, we have discovered that let-7f-5p could suppress the proliferation, migration, and expression of collagen type I alpha 1 (COL1A1) in human dermal fibroblasts (HDFs). It was further determined that let-7f-5p could target thrombospondin-1 (THBS1), thereby inhibiting the TGF-ß2/Smad3 signaling pathway and exerting its biological effects. Additionally, let-7f-5p is regulated by Hsa_circ_0000437, which acts as a sponge molecule for let-7f-5p and consequently regulates the biological function of HDFs. Furthermore, our findings indicate that in vivo overexpression of let-7f-5p leads to a reduction in dermal thickness and COL1A1 expression, effectively inhibiting the progression of bleomycin (BLM)-induced skin fibrosis in mice. Hence, our research enhances the comprehension of the Hsa_circ_0000437/let-7f-5p/THBS1/TGF-ß2/Smad3 regulatory network, highlighting the potential of let-7f-5p as a therapeutic approach for the treatment of skin fibrosis.

5.
J Colloid Interface Sci ; 675: 848-856, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-39002235

ABSTRACT

HYPOTHESIS: The scaling laws of drop pinch-off are known to be affected by drop compositions including dissolved polymers and non-Brownian particles. When the size of the particles is comparable to the characteristic length scale of the polymer network, these particles may interact strongly with the polymer environment, leading to new types of scaling behaviors not reported before. EXPERIMENTS: Using high-speed imaging, we experimentally studied the time evolution of the neck diameter hmin of drops composed of silica nanoparticles dispersed in PEO solution when extruded from a nozzle. FINDINGS: After initial Newtonian necking with hmin âˆ¼ t2/3, the subsequent stage may exhibit scaling variation, characterized by either exponential or power-law decay, depending on the nanoparticle volume fraction ϕ. The exponential decay hmin âˆ¼ e-t/τ signifies the coil-stretch transition in typical viscoelastic suspensions. We conducted an analysis of the power-law scenario hmin âˆ¼ tα at high ϕ, categorizing the entire process into three distinct regimes based on the exponents α. The dependences of critical thicknesses at transition points and exponents on polymer concentration offer initial insights into the potential transition from heterogeneous to homogeneous thinning in the mixture. This novel scaling variation bears implications for accurately predicting and controlling droplet fragmentation in industrial applications.

6.
Sci Adv ; 10(28): eadm9325, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38985876

ABSTRACT

The electrocatalytic nitrate/nitrite reduction reaction (eNOx-RR) to ammonia (NH3) is thermodynamically more favorable than the eye-catching nitrogen (N2) electroreduction. To date, the high eNOx-RR-to-NH3 activity is limited to strong alkaline electrolytes but cannot be achieved in economic and sustainable neutral/near-neutral electrolytes. Here, we construct a copper (Cu) catalyst encapsulated inside the hydrophilic hierarchical nitrogen-doped carbon nanocages (Cu@hNCNC). During eNOx-RR, the hNCNC shell hinders the diffusion of generated OH- ions outward, thus creating a self-enhanced local high pH environment around the inside Cu nanoparticles. Consequently, the Cu@hNCNC catalyst exhibits an excellent eNOx-RR-to-NH3 activity in the neutral electrolyte, equivalent to the Cu catalyst immobilized on the outer surface of hNCNC (Cu/hNCNC) in strong alkaline electrolyte, with much better stability for the former. The optimal NH3 yield rate reaches 4.0 moles per hour per gram with a high Faradaic efficiency of 99.7%. The strong-alkalinity-free advantage facilitates the practicability of Cu@hNCNC catalyst as demonstrated in a coupled plasma-driven N2 oxidization with eNOx-RR-to-NH3.

7.
Front Immunol ; 15: 1407035, 2024.
Article in English | MEDLINE | ID: mdl-38979420

ABSTRACT

Introduction: The Hand, Foot and Mouth Disease (HFMD), caused by enterovirus 71 infection, is a global public health emergency. Severe HFMD poses a significant threat to the life and well-being of children. Numerous studies have indicated that the occurrence of severe HFMD is associated with cytokine storm. However, the precise molecular mechanism underlying cytokine storm development remains elusive, and there are currently no safe and effective treatments available for severe HFMD in children. Methods: In this study, we established a mouse model of severe HFMD to investigate the molecular mechanisms driving cytokine storm. We specifically analyzed metabolic disturbances, focusing on arginine/ornithine metabolism, and assessed the potential therapeutic effects of spermine, an ornithine metabolite. Results: Our results identified disturbances in arginine/ornithine metabolism as a pivotal factor driving cytokine storm onset in severe HFMD cases. Additionally, we discovered that spermine effectively mitigated the inflammatory injury phenotype observed in mice with severe HFMD. Discussion: In conclusion, our findings provide novel insights into the molecular mechanisms underlying severe HFMD from a metabolic perspective while offering a promising new strategy for its safe and effective treatment.


Subject(s)
Arginine , Cytokines , Disease Models, Animal , Hand, Foot and Mouth Disease , Ornithine , Animals , Hand, Foot and Mouth Disease/immunology , Mice , Arginine/metabolism , Humans , Cytokines/metabolism , Spermine/metabolism , Female , Enterovirus A, Human/immunology , Male , Mice, Inbred C57BL , Severity of Illness Index
8.
Endocrine ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38965137

ABSTRACT

PURPOSE: We aimed to investigate the association of the triglyceride glucose-body mass index(TyG-BMI), metabolic score for insulin resistance (METS-IR) with regression to normoglycaemia, and further to compare the value of the four insulin resistance(IR) related indices(TyG-BMI, METS-IR, TyG and triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio) in identifying regressions to normoglycaemia from prediabetes. METHODS: A total of 15,025 patients with prediabetes from the DATA-DRYAD database were included. Cox proportional hazards regression models and restricted cubic spline functions were performed to explore the association and nonlinearity between the indices with the incidence rate of normoglycaemia. Sensitivity and subgroup analyses evaluated the robustness of our findings. RESULTS: Compared with the first quintile, TyG-BMI and METS-IR was negatively linked with the probability of regression to normoglycaemia from prediabetes, the adjusted effect size of the highest quintiles of METS-IR were the most obvious (HR:0.456,95% CI:0.4-0.519), followed by TG/HDL (HR:0.792, 95% CI:0.733-0.856), TyG-BMI (HR:0.816, 95% CI:0.73-0.911) and TyG (HR:0.841, 95% CI: 0.754-0.937) (all p for trend <0.001). A 1.0 SD increase in METS-IR induced a 43% decrease in the probability of regression to normoglycaemia, with 9.8% for TyG-BMI. There were nonlinear associations between TyG-BMI and METS-IR and outcomes, with the inflection point of the TyG-BMI being 218.2 and that of the METS-IR being 37. CONCLUSIONS: The METS-IR might be the most superior indicator among the four non-insulin indices in identifying regressions to normoglycaemia from prediabetes in clinical application. The inflection points of the METS-IR and TyG-BMI may be instructive therapeutic points for assessing the status of prediabetes in advance and making more appropriate management and health care decisions.

9.
Phys Chem Chem Phys ; 26(29): 20022-20036, 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39007185

ABSTRACT

The chemical kinetic studies of hydrogen atom (H-atom) abstraction reactions by hydroperoxyl (HȮ2) radicals from five branched pentanol isomers, including 3-methyl-1-butanol, 2-methyl-1-butanol, 1,1-dimethyl-1-propanol, 1,2-dimethyl-1-propanol, and 2,2-dimethyl-1-propanol were investigated systematically through high-level ab initio calculations. Geometry optimization, frequency analysis, and zero-point energy (ZPE) corrections were performed for six reactants, twenty-three transition states (TSs), and twenty-four products at the M06-2X/6-311++G(d,p) level of theory. The intrinsic reaction coordinate calculation was performed at the same level of theory to confirm the transition state connection. The one-dimensional hindered rotor treatment for low-frequency torsional modes was also treated at the M06-2X/6-311++G(d,p) level of theory. The QCISD(T)/CBS level of theory was used to calculate the single-point energies for the species whose T1 diagnostic value was lower than 0.035. At the same time, the CASPT2/CBS level of theory was used to calculate the single-point energies for the channel in which the T1 diagnostic value of transition states was greater than 0.035. Rate constants for the H-atom abstraction reactions from the five branched pentanol isomers by HȮ2 radicals were calculated by using conventional transition state theory with asymmetric Eckart tunneling corrections in the temperature range of 500-2000 K. Rate constants and branching ratios for the title reactions and the rate rules for ten different H-atom abstraction types were investigated. Temperature-dependent thermochemistry properties for all reactants and products were calculated by the composite methods of G3/G4/CBS-QB3/CBS-APNO, which were in good agreement with the data available in the literature. Rate constants for the H-atom abstraction reactions by HȮ2 radical from branched pentanol isomers were investigated in this work as part I, and those for linear pentanol isomers will be analyzed in part II. All the calculated kinetics and thermochemistry data can be utilized in the model development for branched pentanol isomers oxidation.

10.
Oncol Rep ; 52(3)2024 09.
Article in English | MEDLINE | ID: mdl-39054955

ABSTRACT

Ovarian cancer is a gynecological malignant tumor with the highest mortality rate, and chemotherapy resistance seriously affects patient therapeutic outcomes. It has been shown that the high expression of anti­apoptotic proteins Bcl­2 and Bcl­xL is closely related to ovarian cancer chemotherapy resistance. Therefore, reducing Bcl­2 and Bcl­xL expression levels may be essential for reversing drug resistance in ovarian cancer. ABT­737 is a BH3­only protein mimetic, which can effectively inhibit the expression of the anti­apoptotic proteins Bcl­xL and Bcl­2. Although it has been shown that ABT­737 can increase the sensitivity of ovarian cancer cells to cisplatin, the specific molecular mechanism remains unclear and requires further investigation. In the present study, the results revealed that ABT­737 can significantly increase the activation levels of JNK and ASK1 induced by cisplatin in A2780/DDP cells, which are cisplatin­resistant ovarian cancer cells. Inhibition of the JNK and ASK1 pathway could significantly reduce cisplatin cytotoxicity increased by ABT­737 in A2780/DDP cells, while inhibiting the ASK1 pathway could reduce JNK activation. In addition, it was further determined that ABT­737 could increase reactive oxygen species (ROS) levels in A2780/DDP cells induced by cisplatin. Furthermore, the inhibition of ROS could significantly reduce JNK and ASK1 activation and ABT­737­mediated increased cisplatin cytotoxicity in A2780/DDP cells. Overall, the current data identified that activation of the ROS­ASK1­JNK signaling axis plays an essential role in the ability of ABT­737 to increase cisplatin sensitivity in A2780/DDP cells. Therefore, upregulation the ROS­ASK1­JNK signaling axis is a potentially novel molecular mechanism by which ABT­737 can enhance cisplatin sensitivity of ovarian cancer cells. In addition, the present research can also provide new therapeutic strategies and new therapeutic targets for patients with cisplatin­resistant ovarian cancer with high Bcl­2/Bcl­xL expression patterns.


Subject(s)
Biphenyl Compounds , Cisplatin , Drug Resistance, Neoplasm , MAP Kinase Kinase Kinase 5 , MAP Kinase Signaling System , Nitrophenols , Ovarian Neoplasms , Piperazines , Reactive Oxygen Species , Sulfonamides , Humans , Cisplatin/pharmacology , Female , Drug Resistance, Neoplasm/drug effects , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/metabolism , Ovarian Neoplasms/pathology , Reactive Oxygen Species/metabolism , MAP Kinase Kinase Kinase 5/metabolism , Biphenyl Compounds/pharmacology , Cell Line, Tumor , MAP Kinase Signaling System/drug effects , Sulfonamides/pharmacology , Nitrophenols/pharmacology , Piperazines/pharmacology , Apoptosis/drug effects , Drug Synergism , Gene Expression Regulation, Neoplastic/drug effects , Antineoplastic Agents/pharmacology , JNK Mitogen-Activated Protein Kinases/metabolism
11.
BMJ Case Rep ; 17(6)2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38839409

ABSTRACT

Paraneoplastic pemphigus (PNP) is a rare disease with an unclear mechanism of pathogenesis. We present a case of a male patient who presented with wound management after being diagnosed with Castleman disease-associated paraneoplastic pemphigus (PNP). The patient's condition was not improving; as a result, extensive workup was repeated, which confirmed the diagnosis of aggressive T cell lymphoblastic lymphoma. Our case signifies the importance of keeping a high index of suspicion for PNP-associated malignancies. This case report also adds emphasis to the diagnostic challenges faced by clinicians, making clinical correlation with multidisciplinary approach essential. Therefore, if clinically indicated, we need to revisit the diagnosis and seek alternative explanations to prevent delays in management.


Subject(s)
Paraneoplastic Syndromes , Pemphigus , Humans , Pemphigus/diagnosis , Pemphigus/etiology , Male , Paraneoplastic Syndromes/diagnosis , Castleman Disease/complications , Castleman Disease/diagnosis , Diagnosis, Differential , Middle Aged
12.
Adv Sci (Weinh) ; : e2404323, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38924333

ABSTRACT

Addition of organic compounds containing O/N heteroatoms to aqueous electrolytes such as ZnSO4 (ZS) solutions is one of the effective strategies to inhibit Zn anode dendrites and side reactions. However, addressing the stability of Zn plating/stripping at high current densities and areal capacities by this method is still a challenge, especially in capacitors known for high power and long life. Herein, an organic heterocyclic compound of 1, 4, 7, 10-tetraazacyclododecane (TC) containing four symmetrically distributed N atoms is employed as ZS additive, expanding the life of Zn anodes from ≈ 30 h to 1000 and 240 h at deep plating/stripping conditions of 10 and 20 mA cm-2/mAh cm-2, respectively; the cumulative capacity is as high as 5.0 Ah cm-2 with 99% Coulombic efficiency, far exceeding reported additives. TC with higher binding energies than H2O for Zn species tends to adsorb to Zn (002) in a lying manner and participate in the solvation shell of Zn2+, thus avoiding Zn dendrites and side-reaction damage, especially at high current densities. The TC-endowed Zn anode's stability under such extreme conditions is verified in Zn-ion capacitors (i.e., > 94.6% capacity retention after 28 000 cycles), providing new insights into the development of high-power Zn-based energy storage devices.

13.
Am J Emerg Med ; 83: 25-31, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38943709

ABSTRACT

OBJECTIVE: We aimed to investigate the prognostic factors of pediatric extracorporeal cardiopulmonary resuscitation (ECPR). METHODS: The retrospective study included a total of 77 pediatric cases (7 neonates and 70 children) who underwent ECPR after in-hospital and out-of-hospital cardiac arrest between July 2007 and December 2022. Primary endpoints were complications, while secondary endpoints included all-cause in-hospital mortality. RESULTS: Among the 45 cases experiencing complications, 4 neonates and 41 children had multiple simultaneous complications, primarily neurological issues in 25 cases. Additionally, organ failure occurred in 11 cases, and immunodeficiency was present in two cases. Furthermore, 9 cases experienced bleeding events, and 13 cases showed thrombosis. Patients with complications had lower weight, shorter ECMO durations, and longer CPR durations. Non-survivors had longer CPR durations and shorter durations of ECMO, ICU stay, and mechanical ventilation compared to survivors. Complications were more prevalent in non-survivors, particularly organ failure and bleeding events. CONCLUSION: Weight, CPR duration, and ECMO duration were associated with complications, suggesting areas for treatment optimization. The higher occurrence of complications in non-survivors underscores the importance of early detection and management to improve survival rates. Our findings suggest clinicians consider these factors in prognostic assessments to enhance the effectiveness of ECPR programs.

14.
ACS Nano ; 18(26): 17339-17348, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38905021

ABSTRACT

In recent years, two-dimensional (2D) transition metal dichalcogenides (TMDCs) have been widely recognized as an ideal platform for surface-enhanced Raman scattering (SERS). Given their rich structural phases, phase transformation in 2D TMDCs is an efficient strategy to tailor their SERS performance. In this paper, we present the great SERS performance of multilayer 2M-WS2 and then investigate the effect of its phase transformation on SERS performance. It is observed that multilayer 2M-WS2 nanosheets undergo a thermally induced single-crystal phase transition from 2M-WS2 to 2H-WS2 upon thermal annealing or laser treatment. Distinguishing from the commercially available pure 2H-WS2 (P-2H-WS2), 2H-WS2 obtained by annealing and laser treatment still retain SERS properties comparable to those of 2M-WS2, among which the detection limits for CV molecules (10-8 M) are 3 orders of magnitude lower than that of P-2H-WS2 and the Raman intensity enhancements are ∼10-37 times higher. In contrast to the charge transfer (CT) mechanism governed by the Fermi level in metallic-phase 2M-WS2, 2H-WS2 obtained by phase transition exhibits accelerated CT facilitated by the bandgap reduction and reorganization resulting from the abundance of vacancies. This study introduces an interesting perspective and potential avenue for enhancing SERS through metal-to-semiconductor phase transitions in 2D TMDCs materials.

15.
Sci Rep ; 14(1): 13374, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38862722

ABSTRACT

To reveal the influence mechanism of the grinding surface quality of 20CrMnTi steel components on the tribological characteristics and contact fatigue performance, accelerated tests for sliding friction wear and fatigue damage were carried out. Tribological characteristics and contact fatigue performance get worse with increasing surface roughness while getting better with increasing surface microhardness. Residual compressive stress is conducive to inhibiting the initiation and propagation of cracks and promoting contact fatigue performance. Additionally, mechanical friction, abrasive wear, adhesive wear and fatigue damage coexist and form a competing failure mechanism under the synergistic effect of frictional wear and contact fatigue failure. The damage process mainly manifests as wear, stress concentration induced fatigue, microcracks, pitting, and spalling in the shallow layer. This study is more beneficial to promote the 20CrMnTi steel transmission parts manufacturing products for high precision, low damage, and long life.

16.
Langmuir ; 40(27): 14110-14117, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38937926

ABSTRACT

The complex diffusion behaviors of rod-shaped nanoparticles near the solid-liquid interface are closely related to various biological processes and technological applications. Despite recent advancements in understanding the diffusion dynamics of nanoparticles near some specific solid-liquid interfaces, systematical studies to tune the interfacial interaction or fabricating nonuniform wall to see their effects on the nanorod (NR) diffusion are still lacking. This work utilized molecular dynamics simulations to investigate the rotational and translational diffusion dynamics of a single NR near the solid-liquid interface. We constructed a patterned wall featuring adjustable nonuniformity, which was accomplished by modifying the interaction between NR and the wall, noting that the resulting nonuniformity limits both the translational and rotational diffusion of NR, evident from decreases in diffusion coefficients and exponents. By trajectory analysis, we categorized the diffusion modes of NRs near the patterned wall with varied nonuniformities into three types: Fickian diffusion, desorption-mediated flight, and in-plane diffusion. Furthermore, energy analysis based on the adsorption-desorption mechanism has demonstrated that the three diffusion states are driven by interactions between the NR and the wall, which are primarily influenced by rotational diffusion. These results could significantly deepen the understanding of anisotropic nanoparticle interfacial diffusion and would provide new insights into the transport mechanisms of nanoparticles within confined environments.

18.
J Craniofac Surg ; 35(5): 1523-1530, 2024.
Article in English | MEDLINE | ID: mdl-38830019

ABSTRACT

The aim of this study was to analyze the characteristics and error speech features of cleft-related lateral misarticulation and provide a basis for clinical evaluation and rational intervention. Participants who were diagnosed with lateral misarticulation after cleft palate repairment were 126 children aged 4, 6 to 16, and 11, and they had complete palatopharyngeal closure, no abnormalities in their speech organs and occlusion, and no hearing or intellectual impairments. The Chinese standard pronunciation clarity word list, the American KAY CSL4500, the Beijing Yangchen YF-16 computer speech analysis workstation, soundproof rooms, Wechsler scales of intelligence-fourth edition, and audiometers were used to evaluate the cleft-related lateral misarticulation. Statistical analysis was performed on the age, gender, error rate, corner of the mouth deviation direction, comorbidity, duration of intervention, period of treatment, and therapeutic effect of concentrated or normal intervention group in different patients. Our results showed that 2 to 3 straight stripes were visible at the onset of consonants /ti:/ /t'i:/, and 3 clear straight lines were visible in /tʂ/, indicating that the lateralized sound had 2 or 3 bursts and lasted for 1 to 2 ms. The onset age of lateralized sound was mostly below 12 years old. Chinese lateralized sound mainly occurred in vowel /i:/, and the occurrence rate of consonants with tongue surface /tɕ]/ /tɕ'/ /ɕ/ was the highest. In addition, the corner of the mouth deviation was also an indicator of lateralization sound, and other types of speech disorders mostly accompanied it. There was a significant difference in the improvement of speech clarity between the concentrated intervention group and the normal group before and after treatment. The 2 groups' average duration and course of treatment were not significantly different. Still, the period of concentrated intervention was shortened considerably, and the speech clarity of both groups of children after treatment exceeded 96%, reaching a normal level.


Subject(s)
Articulation Disorders , Cleft Palate , Adolescent , Child , Child, Preschool , Female , Humans , Male , Articulation Disorders/etiology , Articulation Disorders/therapy , China , Cleft Palate/surgery , East Asian People
19.
Adv Mater ; : e2406957, 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38923059

ABSTRACT

Single-atom catalysts (SACs) are flourishing in various fields because of their 100% atomic utilization. However, their uncontrollable selectivity, poor stability and vulnerable inactivation remain critical challenges. According to theoretical predictions and experiments, a heteronuclear CoZn dual-single-atom confined in N/O-doped hollow carbon nanotube reactors (CoZnSA@CNTs) was synthesized via a spatial confinement growth strategy. CoZnSA@CNTs exhibited superior performance for H2O2 electrosynthesis over the entire pH range due to dual-confinement of the atomic sites and O2 molecule. CoZnSA@CNTs was favorable for H2O2 production mainly because the synergy of adjacent atomic sites, defect-rich feature and nanotube reactor promoted O2 enrichment and enhanced H2O2 reactivity/selectivity. The H2O2 selectivity reached nearly 100% in a range of 0.2 ∼ 0.65 V versus RHE and the yield achieved 7.50 M gcat -1 with CoZnSA@CNTs/carbon fiber felt, which exceeded most of the reported SACs in H-type cells. The obtained H2O2 was converted directly to sodium percarbonate and sodium perborate in a safe way for H2O2 storage/transportation. The sequential dual-cathode electron-Fenton process promoted the formation of reactive oxygen species (•OH, 1O2 and •O2 -) by activating the in-situ generated H2O2, enabling accelerated degradation of various pollutants and Cr(VI) detoxification in actual wastewater. This work proposes a promising confinement strategy for catalyst design and selectivity regulation of complex reactions. This article is protected by copyright. All rights reserved.

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