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A simplified column-buckling model is developed to understand the buckling mechanism of thin-walled strips restrained by uniform lateral pressure in the milling process. The strip is simplified as two rigid columns connected by a rotation spring, resting on a smooth surface, restrained by a uniform pressure and loaded by an axial force. Two loading cases are considered, i.e., the dead load and the follower load. Analytical solutions for the post-buckling responses of the two cases are derived based on the energy method. The minimum buckling force, Maxwell force and stability conditions for the two cases are established. It is demonstrated that the application of higher uniform pressure increases the minimum buckling force for the column and thus makes the column less likely to buckle. For the same pressure level, the dead load is found to be more effective than the follower load in suppressing the buckling of the system. The effect of initial geometric imperfection is also investigated, and the imperfection amplitude and critical restraining pressure that prevent buckling are found to be linearly related. The analytical results are validated by finite element simulations. This analytical model reveals the buckling mechanism of strips under lateral pressure restraint, which cannot be explained by the conventional bifurcation buckling theory, and provides a theoretical foundation for buckling-prevention strategies during the milling process of thin-walled strips, plates and shells commonly encountered in aerospace or automotive industries.
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Large-dimension complex integral thin-shell components are widely used in advanced transportation equipment. However, with the dimensional limitations of raw blanks and the manufacturing process, there are inhomogeneous geometric and mechanical properties at welded joints after welding, which have a significant effect on the subsequent forming process. Therefore, in this paper, the microstructure of welded joints with a sharp property change was accurately characterized by the proposed isothermal treatment method using the BR1500HS welded tube as an example. In addition, an accurate constitutive model of welded tubes was established to predict the deformation behavior. Firstly, the heat-treated specimens were subjected to uniaxial tensile tests and the stress-strain curves under different heat treatment conditions were obtained. Then, the continuous change in flow stress in the direction of the base metal zone, the heat-affected zone and the weld zone was described by the relationship between the microhardness, flow stress and center angle of the welded tube. Using such a method, a continuous constitutive model of welded tubes has been established. Finally, the constitutive model was compiled into finite-element software as a user material subroutine (VUHARD). The reliability of the established constitutive model was verified by simulating the free hydro-bulging process of welded tubes. The results indicated that the continuous constitutive model can well describe the deformation response during the free hydro-bulging process, and accurately predicted the equivalent strain distribution and thickness thinning rate. This study provides guidance in accurately predicting the plastic deformation behavior of welded tubes and its application in practice in hydroforming industries.
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Leptomeningeal metastasis (LM) is a devastating complication of advanced non-small cell lung cancer (NSCLC). Its diagnosis and monitoring can be challenging. Recently, extracellular vesicle (EV) miRNAs have become a new noninvasive diagnostic biomarker. The purpose of this study was to examine the clinical value and role of EV miRNAs in NSCLC-LM. Next-generation sequencing analysis revealed that miRNAs with differential expression of EVs in sera of patients with NSCLC with LM and non-LM were detected to identify biological markers for the diagnosis of LM. Cellular and in vivo experiments were conducted to explore the pathogenesis of EV miRNA promoting LM in NSCLC. In the present study, we first demonstrated that the serum level of EV-associated miR-374a-5p in patients with LM of lung cancer was much higher than that in patients without LM and was correlated with the survival time of patients with LM. Further studies showed that EV miR-374a-5p efficiently destroys tight junctions and the integrity of the cerebral microvascular endothelial cell barrier, resulting in increased blood-brain barrier permeability. Mechanistically, miR-374a-5p regulates the distribution of ZO1 and occludin in endothelial cells by targeting γ-adducin, increasing vascular permeability and promoting LM. Implications: These results suggest that serum NSCLC-derived EV miR-374a-5p is involved in premetastatic niche formation by regulating the permeability of the blood-brain barrier to promote NSCLC-LM and can be used as a blood biomarker for the diagnosis and prognosis of NSCLC-LM.
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Barreira Hematoencefálica , Carcinoma Pulmonar de Células não Pequenas , Vesículas Extracelulares , Neoplasias Pulmonares , MicroRNAs , MicroRNAs/genética , MicroRNAs/sangue , MicroRNAs/metabolismo , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Barreira Hematoencefálica/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/sangue , Animais , Camundongos , Masculino , Feminino , Pessoa de Meia-Idade , Linhagem Celular Tumoral , Camundongos Nus , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/secundário , Neoplasias Meníngeas/sangue , Neoplasias Meníngeas/metabolismo , PermeabilidadeRESUMO
The virus that infects bacteria known as phage, plays a crucial role in the biogeochemical cycling of nutrients. However, the community structure and potential functions of phages in silage fermentation remain largely unexplored. In this study, we utilized viral metagenomics (viromics) to investigate the types, lifestyles, functions, and nutrient utilization patterns of phages in silage. Our findings indicated a high prevalence of annotated phages belonging to Caudovirales and Geplafuvirales, as well as unclassified phages in silage. The predominant host types for these phages were Campylobacterales and Enterobacterales. Virulent phages dominated the silage environment due to their broader range of hosts and enhanced survival capabilities. All identified phages present in silage were found to be non-pathogenic. Although temperate and virulent phages carried distinct genes associated with nutrient cycling processes, the shared genes (prsA) involved in carbon metabolism underscore the potential significance of phages in regulating carbon metabolism in silage. Overall, our findings provide a valuable foundation for further exploring the complex interactions between phages and microorganisms in regulating silage fermentation quality.
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Bacteriófagos , Fermentação , Silagem , MetagenômicaRESUMO
There have been few investigations into the health benefits and meat quality of supplementing Yangzhou geese with paper mulberry silage. One hundred and twenty 28-day-old Yangzhou geese were selected for the experiment and randomly divided into two groups: a control group (CON) and a paper mulberry silage group (PM), with six replicates in each group. The experiment lasted for a total of 6 weeks. The experiment found that compared with CON, PM had a promoting effect on the average daily weight gain of Yangzhou geese (p = 0.056). Sensory and nutritional analysis of breast muscles revealed a decrease in a* value (p < 0.05) and an increase in protein content (p < 0.05) following PM treatment. Through untargeted metabolomics analysis of breast muscle samples, it was found that 11 different metabolites, including guanidinoacetic acid and other substances, had a positive effect on amino acid metabolism and lipid antioxidant pathways of PM treatment. Overall, the strategy of feeding Yangzhou geese with paper mulberry silage is feasible, which can improve the sensory quality and nutritional value of goose meat. The experiment provides basic data for the application form of goose breeding, so exploring the impact of substances within paper mulberry on goose meat should be focused on in the future.
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Accidental bleeding is an unavoidable problem in daily life. To avoid the risk of excessive blood loss, it is urgent to design a functional material that can quickly stop bleeding. In this study, an efficient wound dressing for hemostasis was investigated. Based on the characteristics that Ca2+ and fish skin collagen (FSC) could activate the coagulation mechanism, hemostatic cotton was prepared by solvent replacement method using CaCl2, FSC, soluble starch (SS), and polyvinyl alcohol (PVA) as raw materials. The cytotoxicity test showed the Ca2+PVA/FSC-SS hemostatic cottons had good biocompatibility. The activated partial thromboplastin time (APTT) of Ca2+PVA/FSC-SS(4) was 35.34 s, which was 22.07 s faster than that of PVA/FSC-SS, indicating Ca2+PVA/FSC-SS mediated the endogenous coagulation system. In vitro coagulation test, Ca2+PVA/FSC-SS(4) could stop bleeding rapidly within 39.60 ± 5.16 s, and the ability of wound healing was higher than commercial product (Celox). This study developed a rapid procoagulant and hemostatic material, which had a promising application in a variety of environments.
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Hemostáticos , Animais , Hemostáticos/farmacologia , Amido/farmacologia , Hemostasia , Coagulação Sanguínea , Colágeno , Álcool de Polivinil , Hemorragia , Etanol , AntibacterianosRESUMO
Over the past two decades, scientific interest in understanding the relationship between mindfulness and cognition has accelerated. However, despite considerable investigative efforts, pervasive methodological inconsistencies within the literature preclude a thorough understanding of whether or how mindfulness influences core cognitive functions. The purpose of the current study is to provide an initial "proof-of-concept" demonstration of a new research strategy and methodological approach designed to address previous limitations. Specifically, we implemented a novel fully within-subject state induction protocol to elucidate the neurobehavioral influence of discrete mindfulness states-focused attention (FA) and open monitoring (OM), compared against an active control-on well-established behavioral and ERP indices of executive attention and error monitoring assessed during the Eriksen flanker task. Bayesian mixed modeling was used to test preregistered hypotheses pertaining to FA and OM effects on flanker interference, the stimulus-locked P3, and the response-locked ERN and Pe. Results yielded strong but unexpected evidence that OM selectively produced a more cautious and intentional response style, characterized by higher accuracy, slower RTs, and reduced P3 amplitude. Follow-up exploratory analyses revealed that trait mindfulness moderated the influence of OM, such that individuals with greater trait mindfulness responded more cautiously and exhibited higher trial accuracy and smaller P3s. Neither FA nor OM modulated the ERN or Pe. Taken together, our findings support the promise of our approach, demonstrating that theoretically distinct mindfulness states are functionally dissociable among mindfulness-naive participants and that interactive variability associated with different operational facets of mindfulness (i.e., state vs. trait) can be modeled directly.
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Atenção , Eletroencefalografia , Potenciais Evocados , Função Executiva , Atenção Plena , Humanos , Atenção Plena/métodos , Atenção/fisiologia , Masculino , Feminino , Adulto Jovem , Adulto , Função Executiva/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Cognição/fisiologia , Tempo de Reação/fisiologia , Teorema de Bayes , Adolescente , Encéfalo/fisiologia , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologiaRESUMO
The naturally attached phyllosphere microbiota play a crucial role in plant-derived fermentation, but the structure and function of phyllosphere endophytes remain largely unidentified. Here, we reveal the diversity, specificity, and functionality of phyllosphere endophytes in alfalfa (Medicago sativa L.) through combining typical microbial culture, high-throughput sequencing, and genomic comparative analysis. In comparison to phyllosphere bacteria (PB), the fermentation of alfalfa solely with endophytes (EN) enhances the fermentation characteristics, primarily due to the dominance of specific lactic acid bacteria (LAB) such as Lactiplantibacillus, Weissella, and Pediococcus. The inoculant with selected endophytic LAB strains also enhances the fermentation quality compared to epiphytic LAB treatment. Especially, one key endophytic LAB named Pediococcus pentosaceus EN5 shows enrichment of genes related to the mannose phosphotransferase system (Man-PTS) and carbohydrate-metabolizing enzymes and higher utilization of carbohydrates. Representing phyllosphere, endophytic LAB shows great potential of promoting ensiling and provides a novel direction for developing microbial inoculant.
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Lactobacillales , Humanos , Lactobacillales/genética , Fermentação , Silagem , Endófitos/genética , GenômicaRESUMO
In this study, waterborne polyurethane acrylate (WPUA)/MXene nanocomposite films with varying MXene loadings were fabricated using UV-curing technology, where MXene (Ti3C2Tx) was employed as a nanofiller. The microstructure and chemical structure of the WPUA/MXene nanocomposite films were examined by XRD and FTIR, respectively. The water contact angle testing demonstrated that the incorporation of MXene into the nanocomposite films led to an increase in their hydrophilic properties. The tensile strength, the elongation at break, and Young's modulus of the WPUA/MXene nanocomposite coatings exhibited an initial increase followed by a decrease with increasing MXene loadings. Compared to the pure WPUA film, the tensile strength and elongation at break of nanocomposites with 0.077 wt% MXene loading reached their maximum values, which increased by 39.9% and 38.5%, respectively. Furthermore, the glass transition temperature and the thermal stability were both enhanced by MXene to some extent. This study introduces a novel method for utilizing MXene in UV-curable waterborne coatings.
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BACKGROUND: Noncoding RNAs such as circular RNAs (circRNAs) are abundant in the human body and influence the occurrence and development of various diseases. Non-small cell lung cancer (NSCLC) is one of the most common malignant cancers. Information on the functions and mechanism of circRNAs in lung cancer is limited; thus, the topic needs more exploration. The purpose of this study was to identify aberrantly expressed circRNAs in lung cancer, unravel their roles in NSCLC progression, and provide new targets for lung cancer diagnosis and therapy. METHODS: High-throughput sequencing was used to analyze differential circRNA expression in patients with lung cancer. qRTâPCR was used to determine the level of circHERC1 in lung cancer tissues and plasma samples. Gain- and loss-of-function experiments were implemented to observe the impacts of circHERC1 on the growth, invasion, and metastasis of lung cancer cells in vitro and in vivo. Mechanistically, dual luciferase reporter assays, fluorescence in situ hybridization (FISH), RNA immunoprecipitation (RIP) and RNA pull-down experiments were performed to confirm the underlying mechanisms of circHERC1. Nucleocytoplasmic localization of FOXO1 was determined by nucleocytoplasmic isolation and immunofluorescence. The interaction of circHERC1 with FOXO1 was verified by RNA pull-down, RNA immunoprecipitation (RIP) and western blot assays. The proliferation and migration of circHERC1 in vivo were verified by subcutaneous and tail vein injection in nude mice. RESULTS: CircHERC1 was significantly upregulated in lung cancer tissues and cells, ectopic expression of circHERC1 strikingly facilitated the proliferation, invasion and metastasis, and inhibited the apoptosis of lung cancer cells in vitro and in vivo. However, knockdown of circHERC1 exerted the opposite effects. CircHERC1 was mainly distributed in the cytoplasm. Further mechanistic research indicated that circHERC1 acted as a competing endogenous RNA of miR-142-3p to relieve the repressive effect of miR-142-3p on its target HMGB1, activating the MAPK/ERK and NF-κB pathways and promoting cell migration and invasion. More importantly, we found that circHERC1 could bind FOXO1 and sequester it in the cytoplasm, adjusting the feedback AKT pathway. The accumulation of FOXO1 in the cytosol and nuclear exclusion promoted cell proliferation and inhibited apoptosis. CircHERC1 is a new circRNA that promotes tumor function in NSCLC and may serve as a potential prognostic biomarker and therapeutic target for NSCLC. CONCLUSIONS: CircHERC1 is a new circRNA that promotes tumor function in NSCLC and may serve as a potential diagnosis biomarker and therapeutic target for NSCLC. Our findings indicate that circHERC1 facilitates the invasion and metastasis of NSCLC cells by regulating the miR-142-3p/HMGB1 axis and activating the MAPK/ERK and NF-κB pathways. In addition, circHERC1 can promote cell proliferation and inhibit apoptosis by sequestering FOXO1 in the cytoplasm to regulate AKT activity and BIM transcription.
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Carcinoma Pulmonar de Células não Pequenas , Proteína Forkhead Box O1 , Proteína HMGB1 , Neoplasias Pulmonares , MicroRNAs , RNA Circular , Animais , Humanos , Camundongos , Biomarcadores , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Citoplasma/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteína HMGB1/metabolismo , Hibridização in Situ Fluorescente , Neoplasias Pulmonares/genética , Camundongos Nus , MicroRNAs/genética , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Circular/genética , Proteína Forkhead Box O1/metabolismo , Ubiquitina-Proteína Ligases/genéticaRESUMO
Experimental flow stress-strain data under different stress states are often used to calibrate the plastic constitutive model of anisotropic metal materials or identify the appropriate model that is able to reproduce their plastic deformation behavior. Since the experimental stress-strain data are discrete, they need to be mathematically returned to a continuous function to be used to describe an equivalent hardening increment. However, the regression results obtained using existing regression models are not always accurate, especially for stress-strain curves under biaxial stress loading conditions. Therefore, a new regression model is proposed in this paper. The highest-order term in the recommended form of the new model is quadratic, so the functional relationships between stress-strain components can be organized into explicit expressions. All the experimental data of the uniform deformation stage can be substituted into the new model to reasonably reproduce the biaxial experimental stress-strain data. The regression results of experimental data show that the regression accuracy of the new model is greatly improved, and the residual square sum SSE of the regression curves of the new model reduced to less than 50% of the existing three models. The regression results of stress-strain curves show significant differences in describing the yield and plastic flow characteristics of anisotropic metal materials, indicating that accurate regression results are crucial for accurately describing the anisotropic yielding and plastic flow behaviors of anisotropic metal materials.
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INTRODUCTION: Confocal laser endomicroscopy (CLE) has the characteristics of high resolution, real-time imaging, and no radiation, which is helpful for the precise and effective implementation of transbronchial cryobiopsy (TBCB). The study aimed to compare the efficacy and safety of TBCB combined with CLE (CLE group) or fluoroscopy (fluoroscopy group) in the diagnosis of interstitial lung disease (ILD). METHODS: From a prospective randomized controlled trial, 80 patients with undiagnosed ILD or ILD requiring biopsy between January 2022 and November 2022 were randomly assigned to CLE group and fluoroscopy group. The rate to reach an etiological diagnosis of ILD, maximum cross-sectional area of specimens, operation time, and complications were compared between the two groups. RESULTS: The rate to reach an etiological diagnosis in the CLE group was significantly higher than that in the fluoroscopy group (95.0% vs. 80.0%, p < 0.05), but there was no difference in the maximum cross-sectional area of the specimens (42.1 ± 10.1 mm2 vs. 41.5 ± 10.3 mm2, p > 0.05). In terms of operation time, the CLE group was significantly shorter than the fluoroscopy group (37.6 ± 10.6 min vs. 54.8 ± 24.9 min, p < 0.05). The bleeding volume in the CLE group was significantly lower than that in the fluoroscopy group (4.9 ± 3.6 mL/case vs. 9.0 ± 9.2 mL/case, p < 0.05). Further analysis showed that the incidence of moderate bleeding was also lower in the CLE group (20.0% vs. 75.0%, p < 0.001). In addition, the incidence of pneumothorax in the CLE group was significantly lower than that in the fluoroscopy group (0 vs. 25.0%, p < 0.001). CONCLUSIONS: Compared with simple fluoroscopy, the combination of CLE significantly improves the rate of etiological diagnosis, shortens the operation time, and reduces complications such as bleeding and pneumothorax.
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Broncoscopia , Doenças Pulmonares Intersticiais , Humanos , Biópsia/métodos , Broncoscopia/efeitos adversos , Broncoscopia/métodos , Hemorragia , Doenças Pulmonares Intersticiais/patologia , Pneumotórax/patologia , Estudos ProspectivosRESUMO
We propose an experimental method to identify anisotropic coefficients in non-principal axis directions of thin-walled tubes. The method involves extracting specimens from the parent tubes and machining a hole in the axial center. The specimens are then inserted into a tube without a hole. The inner diameter of the specimen is theoretically equal to the outer diameter of the inner tube. The double-layer tube undergoes free bulging under internal pressure in our self-developed experimental equipment, with the hole on the specimen expanding simultaneously. The stress states around the hole are uniaxial, and the hole deformation can reflect the anisotropic plastic flow characteristics of the tube. Furthermore, based on the information obtained from the proposed experimental method, a hybrid numerical-experimental method was used to identify the anisotropic coefficients of tubes. Through FE simulations, the relationships between the thickness, stress, and strain states around the hole, the hole shape, and anisotropic coefficients of non-principal axis directions are revealed, and the factors that affect the hole deformation are analyzed. Finally, the hole bulging experiments and FE simulations of AA6061-O extruded tube were conducted, and modeled with Hill48 and calibrated by uniaxial tensile and hoop tensile tests. Its in-plane anisotropy coefficients in any direction are given for the first time which first increase and then decrease from 0° to 90°, reaching a maximum of 1.13 in 60° and a minimum of 0.69 in 0°. This work can provide the key experimental data for establishing an accurate anisotropic plastic constitutive model of thin-walled tubes.
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The simple shear test shows significant advantages when measuring the hardening and shear properties of thin sheet metal at large strains. However, previous shear tests had an end effect caused by local stress concentration and a boundary effect caused by deformation overflow, resulting in non-uniform strain distribution in the shear zone. Therefore, a unique V-shaped double-shear-zone specimen is proposed to measure the Bauschinger effect under cyclic shear loading conditions in this paper. Simple shear experiments and three different types of cycle shear experiments are conducted to analyze the uniformity of deformation in the shear zone and the effect of pre-strain and the number of cyclic loads on the Bauschinger effect of Q890 high-strength steel sheets. The results indicate that the proposed V-shaped double-shear-zone specimen can still maintain uniform shear deformation in forward/reverse cyclic loading experiments, even at large strains. Q890 high-strength steel exhibits a significant Bauschinger effect, which is more pronounced with the increase in shear pre-strain and loading cycles. The results of this paper provide a new approach for studying the hardening characteristics under large strain and the mechanical properties under cyclic shear loading for metal sheets.
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BACKGROUND: Due to the poor prognosis of gastric cancer (GC), early detection methods are urgently needed. Plasma exosomal circular RNAs (circRNAs) have been suggested as novel biomarkers for GC. AIM: To identify a novel biomarker for early detection of GC. METHODS: Healthy donors (HDs) and GC patients diagnosed by pathology were recruited. Nine GC patients and three HDs were selected for exosomal whole-transcriptome RNA sequencing. The expression profiles of circRNAs were analyzed by bioinformatics methods and validated by droplet digital polymerase chain reaction. The expression levels and area under receiver operating characteristic curve values of plasma exosomal circRNAs and standard serum biomarkers were used to compare their diagnostic efficiency. RESULTS: There were 303 participants, including 240 GC patients and 63 HDs, involved in the study. The expression levels of exosomal hsa_circ_0079439 were significantly higher in GC patients than in HDs (P < 0.0001). However, the levels of standard serum biomarkers were similar between the two groups. The area under the curve value of exosomal hsa_circ_0079439 was higher than those of standard biomarkers, including carcinoembryonic antigen, carbohydrate antigen (CA)19-9, CA72-4, alpha-fetoprotein, and CA125 (0.8595 vs 0.5862, 0.5660, 0.5360, 0.5082, and 0.5018, respectively). The expression levels of exosomal hsa_circ_0079439 were significantly decreased after treatment (P < 0.05). Moreover, the expression levels of exosomal hsa_circ_0079439 were obviously higher in early GC (EGC) patients than in HDs (P < 0.0001). CONCLUSION: Our results suggest that plasma exosomal hsa_circ_0079439 is upregulated in GC patients. Moreover, the levels of exosomal hsa_circ_0079439 could distinguish EGC and advanced GC patients from HDs. Therefore, plasma exosomal hsa_circ_0079439 might be a potential biomarker for the diagnosis of GC during both the early and late stages.
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Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Detecção Precoce de Câncer , RNA Circular , Antígeno CA-19-9 , Biologia ComputacionalRESUMO
Endobronchial ultrasound bronchoscopy (EBUS) and needle confocal laser endomicroscopy (nCLE) are techniques for screening benign and malignant lesions of the hilar and mediastinal lymph node (HMLN). This study investigated the diagnostic potential of EBUS, nCLE, and combined EBUS and nCLE in HMLN lesions. We recruited 107 patients with HMLN lesions who were examined by EBUS and nCLE. A pathological examination was performed, and the diagnostic potential of EBUS, nCLE, and combined EBUS-nCLE approach was analyzed according to the results. Among the 107 cases of HMLN lesions, 43 cases were benign and 64 cases were malignant on pathological examination, 41 cases were benign and 66 cases were malignant on EBUS examination; 42 cases were benign and 65 cases were malignant on nCLE examination; 43 cases were benign and 64 cases were malignant on combined EBUS-nCLE examination. The combination approach had 93.8% sensitivity, 90.7% specificity, and 0.922 area under the curve, which was higher than those of EBUS (84.4%, 72.1%, and 0.782, respectively) and nCLE diagnosis (90.6%, 83.7%, and 0.872, respectively). The combination approach had a higher positive predictive value (0.908), negative predictive value (0.881), and positive likelihood ratio (10.09) than that of EBUS (0.813, 0.721, and 3.03, respectively) and nCLE (0.892, 0.857, and 5.56, respectively), whereas, the negative likelihood ratio was lower than that for EBUS (0.22) and nCLE (0.11). No serious complications occurred in patients with HMLN lesions. To summarize, the diagnostic efficacy of nCLE was better than EBUS. The EBUS-nCLE combination is a suitable approach for diagnosing HMLN lesions.
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Broncoscopia , Neoplasias Pulmonares , Humanos , Broncoscopia/métodos , Mediastino/diagnóstico por imagem , Mediastino/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Pulmão/patologia , Sensibilidade e Especificidade , Estudos RetrospectivosRESUMO
To meet the requirement of lighter weight and better performance in tube hydroforming, one of the most important tasks is to accurately predict the forming limit of thin-walled tubes under nonlinear loading paths. This work established the M-K+DF2012 model, a combination of the M-K model and the DF2012 ductile fracture criterion, for the forming limit prediction of thin-walled tubes under nonlinear loading paths. In this model, the failure of the groove is determined by the DF2012 criterion, and the corresponding strains in the uniform region are the limit strains. The limit strains of an AA6061 aluminum alloy tube under a set of linear loading paths and two typical nonlinear loading paths were tested. Parameter values of the M-K+DF2012 model for the tube were determined based on the experimental limit strains under linear loading paths, and the limit strains under the two nonlinear loading paths were predicted. Then the strain-based forming limit diagram (ε-FLD) and the polar effective plastic strain FLD (PEPS-FLD) of the tube under different pre-strains were predicted and discussed. The results show that the limit strains of the tube are obviously path-dependent, and the M-K+DF2012 model can reasonably capture the limit strains of the tube under both linear and nonlinear loading paths. The predicted ε-FLD shows a strong dependence on the pre-strain, while the predicted PEPS-FLD is weakly strain path-dependent and almost path-independent on the right-hand side for the AA6061 tube.
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In sheet metal forming, the material is usually subjected to a complex nonlinear loading process, and the anisotropic hardening behavior of the material must be considered in order to accurately predict the deformation of the sheet. In recent years, the homogeneous anisotropic hardening (HAH) model has been applied in the simulation of sheet metal forming. However, the existing HAH model is established in the second-order stress deviator space, which makes the calculation complicated and costly, especially for a plane stress problem such as sheet metal forming. In an attempt to reduce the computational cost, an HAH model in plane stress state is proposed, and called the HAH-2d model in this paper. In the HAH-2d model, both the stress vector and microstructure vector contain only three in-plane components, so the calculation is significantly simplified. The characteristics of the model under typical nonlinear loading paths are analyzed. Additionally, the feasibility of the model is verified by the stress-strain responses of DP780 and EDDQ steel sheets under different two-step uniaxial tension tests. The results show that the HAH-2d model can reasonably reflect the Bauschinger effect and the permanent softening effect in reverse loading, and the latent hardening effect in cross loading, while the predictive accuracy for cross-loading softening remains to be improved. In the future, the HAH-2d model can be further modified to describe more anisotropic hardening behaviors and applied to numerical simulations.
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Circular RNAs (circRNAs) are a specialized circular structure, are deregulated in cancers and play essential roles in biological processes involved in tumor progression. However, the mechanism by which circRNAs affect lung tumorigenesis and progression remains largely unexplored. To investigate the role of circRNA in lung cancer, circRNA expression profile was screened by bioinformatics analysis. The levels of circTAB2, miR-3142, and GLIS family zinc finger 2 (GLIS2) were measured by quantitate real-time (qRT-PCR) or western blot. Cell proliferation, apoptosis, migration and invasion were detected by EdU, flow cytometry, and transwell assays, respectively. Bioinformatics, western blot, RIP, pull down, dual luciferase reporter and rescue experiments were used to verify the direct relationship between miR-3142 and circTAB2 or GLIS2. The xenograft assays were used to assess the role of circTAB2 in vivo.CircTAB2 exhibited low expression in cancer tissues. Gain and loss-of-function assays indicated that circTAB2 could inhibit cell proliferation, migration and invasion. Functional studies revealed that circTAB2 acted as a miRNA sponge, directly interacted with miR-3142 and consequently regulated GLIS2 /AKT. Taken together, circTAB2 serves as an inhibitory role in lung cancer through a novel circTAB2 /miR-3142 /GLIS2 /AKT pathway and could be exploited a novel marker in lung cancer.
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Neoplasias Pulmonares , MicroRNAs , Humanos , Apoptose , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Circular/genética , RNA Circular/metabolismoRESUMO
The hard texture and poor palatability of straw are important factors that hinder its application in feed. Expansion is a technology that can improve the utilization of biomass, but few studies have comprehensively revealed how to change physicochemical characteristics to improve nutritional value. In this study, mechanical and chemical methods were combined to study the texture properties, rheological properties, and physicochemical structures of straw, and its utilization value was evaluated by in vitro rumen digestion. Expansion caused hemicellulose degradation, cellulose separation, and lignin redistribution, resulting in a decrease in crystallinity. The hardness and chewiness of expanded straw were reduced by 55% to 66%, significantly improving palatability. The compressive stress could be reduced by 54-73%, and the relaxation elasticity was reduced by 5% when expanded straw was compressed. The compression deformation of expanded straw was doubled compared to feedstock, and the compacting degree was improved. Expanded straw significantly improved digestibility and gas production efficiency, which was due to the pore structure increasing the attachment of rumen microorganisms; besides that, the reduction of the internal structural force of the straw reduced energy consumption during digestion. The lignin content decreased by 10%, the hardness decreased further in secondary expansion, but the digestibility did not improve significantly.