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1.
Small ; 20(21): e2309961, 2024 May.
Article in English | MEDLINE | ID: mdl-38098343

ABSTRACT

Different phases of Ga2O3 have been regarded as superior platforms for making new-generation high-performance electronic devices. However, understanding of thermal transport in different phases of nanoscale Ga2O3 thin-films remains challenging, owing to the lack of phonon transport models and systematic experimental investigations. Here, thermal conductivity (TC) and thermal boundary conductance (TBC) of the ( 1 ¯ 010 ) $( {\bar 1010} )$ α-, ( 2 ¯ 01 ) $( {\bar 201} )\;$ ß-, and (001) κ-Ga2O3 thin films on sapphire are investigated. At ≈80 nm, the measured TC of α (8.8 W m-1 K-1) is ≈1.8 times and ≈3.0 times larger than that of ß and κ, respectively, consistent with model based on density functional theory (DFT), whereas the model reveals a similar TC for the bulk α- and ß-Ga2O3. The observed phase- and size-dependence of TC is discussed thoroughly with phonon transport properties such as phonon mean free path and group velocity. The measured TBC at Ga2O3/sapphire interface is analyzed with diffuse mismatch model using DFT-derived full phonon dispersion relation. Phonon spectral distribution of density of states, transmission coefficients, and group velocity are studied to understand the phase-dependence of TBC. This study provides insight into the fundamental phonon transport mechanism in Ga2O3 thin films and paves the way for improved thermal management of high-power Ga2O3-based devices.

2.
Lipids Health Dis ; 23(1): 181, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38867213

ABSTRACT

INTRODUCTION: Although there has been abundant evidence of the association between dyslipidemia as a single factor and osteoporosis, the non-linear relationship between osteoporosis and the Atherogenic Index of Plasma (AIP) has not yet been thoroughly investigated. This study aimed to investigate the complex relationship between AIP and bone mineral density (BMD) to elucidate their interrelationship. METHODS: An analysis of 2007-2018 National Health and Nutrition Survey (NHANES) data was conducted for this study. The study enrolled 5,019 participants. Logarithmically multiplying triglycerides and high-density lipoprotein cholesterol yields the AIP (base 10). The measured variables consisted of BMD in the total femur (TF), femoral neck (FN), and lumbar spine (LS). The association between AIP and BMD was examined using a range of statistical models, such as weighted multivariable logistic regression, generalized additive model, etc. RESULTS: It was found that AIP was positively associated with BMD after adjusting for age, gender, race, socioeconomic status, degree of education, income, Consuming alcoholic beverages, osteoporosis status (Yes or No), ALT, AST, serum creatinine, and total calcium levels. Further studies supported the association link between elevated BMD and AIP. Furthermore, compared to men, females had a higher positive connection between AIP and BMD. In general, there was a curve in the reverse L-shape seen, with a point of change around 0.877, indicating a relationship between AIP and TF BMD. Moreover, a curve exhibiting an L-formed pattern, with a point of inflection at around 0.702, was seen between AIP and FN BMD. In addition, a J-shaped curve was seen, with a point of inflection at 0.092, which demonstrates the association between AIP and LS BMD. CONCLUSION: The AIP and TF BMD curves resemble inverted L shapes, as do the AIP and FN BMD curves. The relationship between AIP and LS BMD was further demonstrated by a J-shaped curve. The results indicate a possible association between AIP and bone mineral density, which should be explored in more detail.


Subject(s)
Atherosclerosis , Bone Density , Osteoporosis , Humans , Male , Female , Middle Aged , Cross-Sectional Studies , Atherosclerosis/blood , Osteoporosis/blood , Adult , Cholesterol, HDL/blood , Triglycerides/blood , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/pathology , Femur Neck/diagnostic imaging , Aged , Nutrition Surveys , Femur/diagnostic imaging , Femur/physiopathology
3.
Microb Cell Fact ; 21(1): 37, 2022 Mar 12.
Article in English | MEDLINE | ID: mdl-35279147

ABSTRACT

BACKGROUND: The study and application of microbial consortia are topics of interest in the fields of metabolic engineering and synthetic biology. In this study, we report the design and optimisation of Elizabethkingia meningoseptica and Escherichia coli co-culture, which bypass certain limitations found during the molecular modification of E. meningoseptica, such as resistance to many antibiotics and fewer available molecular tools. RESULTS: The octaprenyl pyrophosphate synthase from E. meningoseptica sp. F2 (EmOPPS) was expressed, purified, and identified in the present study. Then, owing to the low vitamin K2 production by E. coli or E. meningoseptica sp. F2 monoculture, we introduced the E. meningoseptica and E. coli co-culture strategy to improve vitamin K2 biosynthesis. We achieved production titres of 32 mg/L by introducing vitamin K2 synthesis-related genes from E. meningoseptica sp. F2 into E. coli, which were approximately three-fold more than the titre achieved with E. meningoseptica sp. F2 monoculture. This study establishes a foundation for further engineering of MK-n (n = 4, 5, 6, 7, 8) in a co-cultivation system of E. meningoseptica and E. coli. Finally, we analysed the surface morphology, esterase activity, and membrane permeability of these microbial consortia using scanning electron microscopy, confocal laser scanning microscopy, and flow cytometry, respectively. The results showed that the co-cultured bacteria were closely linked and that lipase activity and membrane permeability improved, which may be conducive to the exchange of substances between bacteria. CONCLUSIONS: Our results demonstrated that co-culture engineering can be a useful method in the broad field of metabolic engineering of strains with restricted molecular modifications.


Subject(s)
Chryseobacterium , Flavobacteriaceae Infections , Escherichia coli/genetics , Escherichia coli/metabolism , Humans , Microbial Consortia/genetics , Vitamin K 2/metabolism
4.
Sensors (Basel) ; 22(6)2022 Mar 16.
Article in English | MEDLINE | ID: mdl-35336453

ABSTRACT

Stress detection of the conical frustum window is a very important issue to ensure the safety of deep manned submersibles. In this paper, we propose a method based on polarization imaging to evaluate the stress accumulation and recovery in the conical frustum window. An experimental setup of Mueller matrix polarimetry is built, and the samples are made by referring to the typical conical frustum windows in submersibles. By pressurizing different pressures on the samples, we can find the changes of their Mueller matrix images and further derived polarization parameters. The results show that the polarization parameters can characterize the stress transfer process and the elastic-plastic transformation process of the window under different pressurization pressures. We also use a two-layered wave plate model to simulate the stress distribution in the window, which reveals different performances of the former and latter layers of the window under pressurization. Finally, we use a finite element model to simulate and understand some of the above experimental results. This proposed method is expected to provide new possibilities for monitoring the window stress and further ensure the safety of deep manned submersibles.


Subject(s)
Diagnostic Imaging , Refraction, Ocular , Spectrum Analysis
5.
Nanotechnology ; 32(47)2021 Sep 02.
Article in English | MEDLINE | ID: mdl-34388741

ABSTRACT

The material, electrical and ultraviolet optoelectronic properties of few layers bottom molybdenum disulfide (MoS2) field effect transistors (FETs) device was investigated before and after 1 MeV electron irradiation. Due to the participation of SiO2in conduction, we discovered novel photoelectric properties and a relatively long photogenerated carrier lifetime (several tens of seconds). Electron irradiation causes lattice distortion, the decrease of carrier mobility, and the increase of interface state. It leads to the degradation of output characteristics, transfer characteristics and photocurrent of the MoS2FET.

6.
Nanotechnology ; 30(48): 485201, 2019 11 29.
Article in English | MEDLINE | ID: mdl-31430726

ABSTRACT

The effects of space radiation on the structural and electrical properties of MoS2 field effect transistors (FETs) were investigated. The 1 MeV electronically equivalent International Space Station (ISS) track was used to apply fluence equivalent to the orbital for 10 (1.0 × 1012 cm-2) and 30 years (3.0 × 1012 cm-2) using the AP8 and AE8 models. X-ray photoelectron spectroscopy (XPS), Raman and photoluminescence (PL) spectra were recorded before and after irradiation. Electron irradiation produced strong desulfurization effects in MoS2 FETs. The PL spectra before and after irradiation did not change significantly, while the [Formula: see text] and A1g Raman modes were red- and blue-shifted, respectively. The XPS results demonstrated a strong desulfurization effect of the electron beam on MoS2. This reduction indicates a much higher amount of irradiation-induced S vacancies compared to Mo vacancies. The electrical characteristics of the device were measured before and after irradiation. The increase in the channel leakage current after irradiation was attributed to the oxide trapping positive charges. MoS2 FETs irradiated by the electron-beam demonstrated a decreased current. This phenomenon can be attributed to the combination of the states at the SiO2/MoS2 interfaces and Coulomb scattering. Our study provides a deeper understanding of the influence of 1 MeV electron-beam irradiation on MoS2-based nano-electronic devices for future space applications.

7.
Phys Chem Chem Phys ; 21(27): 14745-14752, 2019 Jul 10.
Article in English | MEDLINE | ID: mdl-31218305

ABSTRACT

Calculations using the Heyd-Scuseria-Ernzerhof screened hybrid functional reveal the detailed influence that surface vacancies have on the electronic and optical properties of low-dimensional (LD) ß-Ga2O3. Vacancies manifest subtle changes to the electronic characteristics as oxygen states predominate the valence band at the surface. Dielectric functions at the surface are found to increase with vacancies and defects. A broad impact on optical properties, such as absorption coefficients, reflectivity, refractive indices, and electron loss, is seen with increased vacancy defects. Both visible and infrared regions show direct correlation with vacancies while there is a marked decrease in the deep ultraviolet (UV) region. These calculations on the ß-Ga2O3 model system may guide the rational design of two-dimensional optical devices with minimized van der Waals forces.

8.
J Clin Lab Anal ; 33(3): e22701, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30350885

ABSTRACT

BACKGROUND: Early diagnosis of hepatitis C virus (HCV) infection is very important for the treatment of the disease. Development of sensitive and specific rapid detection assays is of great significance for the diagnosis. Here, we describe a promising method of using gold-labeled streptavidin fusion proteins as novel signal reporter in a rapid detection assay for HCV infection. METHODS: Recombinant genes encoding streptavidin fused with Escherichia coli maltose-binding protein (MBP) or with a portion of bacterial translational initiation factor 2 were cloned in expression vectors pMAL-5CX and pET28 and transformed in proper Escherichia coli host strains. The genes were induced and streptavidin fusion proteins, named M-STV and IF-STV, respectively, were purified by affinity chromatography to over 90% purity. The biotin-binding activity of M-STV and IF-STV was tested by enzyme-linked immunosorbent assay (ELISA). M-STV was labeled with colloidal gold nanoparticles and used as a signal reporter to develop a lateral flow-based rapid test for detecting anti-HCV antibodies in human blood samples. RESULTS: M-STV showed slightly higher biotin-binding activity and similar binding specificity as compared to commercial streptavidin. The gold-labeled M-STV bound specifically to biotin moieties immobilized on the rapid test strips in a dose-responsive manner and was successfully used in detecting HCV antibodies in serum samples of patients infected with HCV. The rapid test displayed higher detection sensitivity than gold-labeled commercial NeutrAvidin. CONCLUSION: Our results indicate that gold-labeled M-STV is a promising agent in rapid tests of HCV infection and possibly other viral infections.


Subject(s)
Gold Colloid/chemistry , Hepatitis C/diagnosis , Recombinant Fusion Proteins/metabolism , Streptavidin/metabolism , Enzyme-Linked Immunosorbent Assay/methods , Escherichia coli Proteins/chemistry , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Hepatitis Antibodies/blood , Humans , Periplasmic Binding Proteins/chemistry , Periplasmic Binding Proteins/genetics , Periplasmic Binding Proteins/metabolism , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Streptavidin/chemistry , Streptavidin/genetics
9.
Anticancer Drugs ; 29(10): 935-943, 2018 11.
Article in English | MEDLINE | ID: mdl-30074936

ABSTRACT

Overexpression of insulin growth factor 1 receptor (IGF-1R) and its ligand, insulin growth factor 1 (IGF-1), is related to treatment resistance and worse prognosis in many types of tumors. We reported recently that IGF-1R activation by IGF induces resistance to alectinib and stimulates the production of vascular endothelial growth factor, which indicates that IGF induces alectinib resistance and angiogenesis. This study aimed to determine the effect of bigeminal inhibition of anaplastic lymphoma kinase (ALK) and angiogenesis on human insulin growth factor 1 receptor (hIGF-1)-triggered drug resistance in echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK)-positive lung cancer. Human lung adenocarcinoma H3122 and H2228 cells were exposed to a combination of insulin growth factor 1 receptor (IGF-1), alectinib, or apatinib. The effects of the combination therapy were examined using cell the Cell Counting Kit-8 assay, the colony-forming assay, the scratch test, and flow cytometry analysis, and the molecular mechanism was assessed by western blot. At nontoxic concentrations, apatinib restored alectinib sensitivity by increasing drug-induced apoptosis and inhibiting viability, migration, and invasion in IGF-triggered drug resistant cells. Moreover, we found that apatinib restored sensitivity to alectinib mainly through suppression of the ALK downstream signaling pathway and antiangiogenesis signaling. Taken together, our results indicate that simultaneous inhibition of ALK and vascular endothelial growth factor R2 by the combination of alectinib with apatinib may be useful for controlling progression of EML4-ALK fusion gene lung cancer by reversing ALK-TKI resistance and inhibiting angiogenesis.


Subject(s)
Adenocarcinoma of Lung/drug therapy , Carbazoles/pharmacology , Lung Neoplasms/drug therapy , Piperidines/pharmacology , Pyridines/pharmacology , Adenocarcinoma of Lung/pathology , Anaplastic Lymphoma Kinase/antagonists & inhibitors , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Drug Resistance, Neoplasm , Humans , Insulin-Like Growth Factor I/administration & dosage , Lung Neoplasms/pathology , Oncogene Proteins, Fusion/metabolism , Protein Kinase Inhibitors/pharmacology , Receptor, IGF Type 1/metabolism , Signal Transduction/drug effects , Vascular Endothelial Growth Factor Receptor-2/metabolism
10.
World J Surg Oncol ; 13: 80, 2015 Feb 25.
Article in English | MEDLINE | ID: mdl-25884382

ABSTRACT

BACKGROUND: In a previous analysis using a lung cancer cell line model, we have found that therapies directed against secreted clusterin (sCLU) and its downstream signaling targets pAkt and pERK1/2 may have the potential to enhance the efficacy of cisplatin (DDP)-based chemotherapy in vitro. Here, we investigated the therapies directed against sCLU on the DDP-based chemotherapy in vivo and explored the mechanism. METHODS: Using lung cancer cell lines, A549 cells and DDP-resistant A549 cells (A549(DDP)), we determined the effect of sCLU silencing using short interfering double-stranded RNA (siRNA) on chemosensitivity in immunocompromised mice bearing A549(DDP) tumors. We then determined the effect of sCLU overexpression via stable sCLU transfection on chemosensitivity in immunocompromised mice bearing A549 tumors. The effect of sCLU silencing or overexpression on pAkt and pERK1/2 expression and chemosensitivity in vivo was detected by Western blot assay. RESULTS: The results showed sCLU silencing increased the chemosensitivity of A549(DDP) cells to DDP in vivo via downregulation of pAkt and pERK1/2 expression. And sCLU overexpression decreased the chemosensitivity of A549 cells to DDP in vivo via upregulation of pAkt and pERK1/2 expression. CONCLUSIONS: We therefore concluded that the DDP-induced sCLU activation, which involved induction of pAkt and pERK1/2 activation that confer DDP resistance in immunocompromised mice and alteration of this balance, allows sensitization to the antitumor activity of cisplatin chemotherapy.


Subject(s)
Cisplatin/pharmacology , Clusterin/metabolism , Drug Resistance, Neoplasm , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Animals , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Blotting, Western , Cell Proliferation/drug effects , Clusterin/antagonists & inhibitors , Clusterin/genetics , Humans , Lung Neoplasms/genetics , Male , Mice , Mice, Nude , RNA, Small Interfering/genetics , Signal Transduction/drug effects , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
11.
Phys Rev Lett ; 113(25): 252301, 2014 Dec 19.
Article in English | MEDLINE | ID: mdl-25554876

ABSTRACT

Using a multiphase transport model (AMPT) we calculate the elliptic v_{2} and triangular v_{3} Fourier coefficients of the two-particle azimuthal correlation function in proton-nucleus (p-Pb) and peripheral nucleus-nucleus (Pb-Pb) collisions. Our results for v_{3} are in a good agreement with the CMS data collected at the Large Hadron Collider. The v_{2} coefficient is very well described in p-Pb collisions and is underestimated for higher transverse momenta in Pb-Pb interactions. The characteristic mass ordering of v_{2} in p-Pb is reproduced, whereas for v_{3}, this effect is not observed. We further predict the pseudorapidity dependence of v_{2} and v_{3} in p-Pb and observe that both are increasing when going from a proton side to a Pb-nucleus side. Predictions for the higher-order Fourier coefficients, v_{4} and v_{5}, in p-Pb are also presented.

12.
Article in English | MEDLINE | ID: mdl-38598525

ABSTRACT

Surface-active bonding (SAB) is a promising technique for semiconductors directly bonding. However, the interlayer of the bonding interface and the reduced layer thickness may affect thermal transport. In this study, the temperature-dependent cross-plane thermal conductivity of 4H-SiC thin films and the effective thermal boundary resistance (TBReff) of the bonding SiC-on-SiC are measured by the multiple-probe wavelength nanosecond transient thermoreflectance (MW-TTR). The measured temperature-dependent cross-plane thermal conductivity of the 4H-SiC thin film exhibits good quantitative agreement with calculation by density functional theory (DFT) including higher-order four-phonon (4ph) scattering, especially at high temperatures (>400 K). The theoretical calculations indicate the non-negligible importance of 4ph scattering in 4H-SiC high-temperature applications, due to the significantly increasing 4ph scattering rate at increasing temperature and strong temperature dependence of 4ph scattering. The measured nonzero but small TBReff (2.33 + 0.43/-1.15 m2 K/GW) at the SiC-SiC interface is analyzed with molecular dynamics (MD) simulation, indicating that a strong bonding interface with an extremely thin interlayer is formed by the SAB process. Two-dimensional finite element simulations of the experimental equivalent structures are further investigated, and the significant effects (at least 19 °C) of TBReff on the maximum temperature (Tmax) are confirmed. This study provides insight into the fundamental phonon transport and interface thermal transport mechanism in SAB SiC-on-SiC and paves the way for improved 4H-SiC efficient device manufacturing and thermal management.

13.
ACS Nano ; 18(3): 2520-2530, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38197377

ABSTRACT

Stretchable flexible strain sensors based on conductive elastomers are rapidly emerging as a highly promising candidate for popular wearable flexible electronic and soft-mechanical sensing devices. However, due to the intrinsic limitations of low fidelity and high hysteresis, existing flexible strain sensors are unable to exploit their full application potential. Herein, a design strategy for a successive three-dimensional crack conductive network is proposed to cope with the uncoordinated variation of the output resistance signal arising from the conductive elastomer. The electrical characteristics of the sensor are dominated by the successive crack conductive network through a greater resistance variation and a concise sensing mechanism. As a result, the developed elastomer bionic strain sensors exhibit excellent sensing performance in terms of a smaller overshoot response, a lower hysteresis (∼2.9%), and an ultralow detection limit (0.00179%). What's more, the proposed strategy is universal and applicable to many conductive elastomers with different conductive fillers (including 0-D, 1-D, and 2-D conductive fillers). This approach improves the sensing signal accuracy and reliability of conductive elastomer strain sensors and holds promising potential for various applications in the fields of e-skin and soft robotic systems.

14.
Medicine (Baltimore) ; 103(5): e37125, 2024 Feb 02.
Article in English | MEDLINE | ID: mdl-38306548

ABSTRACT

BACKGROUND: The blood-spinal cord barrier (BSCB) is a unique protective barrier located between the circulatory system and the central nervous system. BSCB plays a vital role in various diseases. However, there is little systematic research and recording in this field by bibliometrics analysis. We aim to visualize this field through bibliometrics to analyze the hotspots and trends of BSCB and in order to facilitate an understanding of future developments in basic and clinical research. METHODS: To conduct a bibliometric study of original publications and their references, the keywords Blood Spinal-Cord Barrier and BSCB are searched and filtered from the Web of Science database (2000-2022), focusing on citations, authors, journals, and countries/regions. Additionally, clustering of the references and co-citation analysis was completed, including a total of 1926 articles and comments. RESULTS: From the results, 193 authors were identified, among which Sharma Hs played a key role. As far as the analysis result of the clustering of the references is concerned, the most common type in cluster analysis is spinal cord injury (SCI) which is a current and developing research field. The keywords are also the specific content under these clusters. The most influential organization is Univ Calif San Francisco, and "Proceedings of The National Academy of Sciences of The United States of America" magazine is the most cited magazine. CONCLUSION SUBSECTIONS: The research on BSCB is booming focusing mainly on "BSCB in SCI" including "activation," "pathway," and "drug delivery" which is also the trend of future research.


Subject(s)
Fetal Blood , Spinal Cord Injuries , Humans , Central Nervous System , Bibliometrics
15.
Biomimetics (Basel) ; 9(1)2024 Jan 03.
Article in English | MEDLINE | ID: mdl-38248598

ABSTRACT

Legged robots have shown great adaptability to various environments. However, conventional walking gaits are insufficient to meet the motion requirements of robots. Therefore, achieving high-speed running for legged robots has become a significant research topic. In this paper, based on the Spring-Loaded Inverted Pendulum (SLIP) model and the optimized Double leg-Spring-Loaded Inverted Pendulum (D-SLIP) model, the running control strategies for the double flying phase Bound gait and the Rotatory gallop gait of quadruped robots are designed. First, the dynamics of the double flying phase Bound gait and Rotatory gallop gait are analyzed. Then, based on the "three-way" control idea of the SLIP model, the running control strategy for the double flying phase Bound gait is designed. Subsequently, the SLIP model is optimized to derive the D-SLIP model with two touchdown legs, and its dynamic characteristics are analyzed. And the D-SLIP model is applied to the running control strategy of the Rotatory gallop gait. Furthermore, joint simulation verification is conducted using Adams virtual prototyping and MATLAB/Simulink control systems for the designed control strategies. Finally, experimental verification is performed for the double flying phase Bound gait running control strategy. The experimental results demonstrate that the quadruped robot can achieve high-speed and stable running.

16.
Materials (Basel) ; 16(13)2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37445047

ABSTRACT

Safety of the observation window is one of the core concerns for manned submersibles. When subjected to underwater static pressure, extrusion and creep deformation always occur in the observation window, which can pose a threat to both safety and optical performance. To assess the deformation, real-time and non-contact monitoring methods are necessary. In this study, a conceptual setup based on the waveplate rotation and dual-DoFP (division of focal-plane polarimeter) polarization camera is built for the observation window's creep monitoring by measuring the Mueller matrix images of the samples under different pressures and durations. Then, a series of characteristic parameters, such as t1, R, r, R', are extracted from the Muller matrix images by Mueller matrix transformation (MMT), Mueller matrix polar decomposition (MMPD), correlation analysis and phase unwrapping method. The results demonstrate that these parameters can effectively describe the observation window's creep at different pressure levels which are simulated by finite element analysis. Additionally, more characterization parameters, such as ψ, A and D, are given from the Mueller matrix images and discussed to illustrate the method's potential for further applications and investigations. Ultimately, future devices based on this method could serve as a valuable tool for real-time and non-contact creep monitoring of the submersible observation windows.

17.
Biomimetics (Basel) ; 9(1)2023 Dec 31.
Article in English | MEDLINE | ID: mdl-38248587

ABSTRACT

The joint hydraulic drive unit (HDU) serves as a pivotal element in enabling the high-performance movements of legged robots. Functioning as the conduit linking the oil source and the actuator, the hydraulic flow channel significantly impacts actuator performance. Hence, optimizing the HDU flow channel becomes imperative, enhancing not only HDU efficiency but also the overall system performance. This paper introduces a novel approach by aligning the hydraulic flow channel of the joint HDU with the arteriovenous layout of the cardiac vascular system, departing from the conventional machining flow channel model. Through simulations determining the optimal range of the vascular branch radius and angle, this study guides the design optimization of the joint HDU flow channel. With the primary optimization goal of reducing pressure loss, the study compares simulation outcomes of various flow channel models-linear, variable excessive radius, and the multidimensional Bessel curve-tailored to suit the arrangement specifics of the joint HDU. Further validating these designs, the flow channels are fabricated using additive manufacturing for experimental verification. The integration of simulation analyses and pressure loss testing reveals a remarkable reduction of over 40% in pressure loss for the bionic flow channel compared to the conventional machining form. This empirical evidence strongly substantiates the bionic flow channel's superior efficacy in pressure loss reduction. The findings presented herein offer valuable insights for the development of low-loss flow channels in joint HDUs, thereby presenting a new avenue for designing energy-efficient, high power-to-weight ratio legged robots.

18.
Ann Surg Oncol ; 19(3): 817-25, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21861215

ABSTRACT

BACKGROUND: YKL-40 is a member of the mammalian chitinase-like proteins. Elevated serum YKL-40 levels in patients with gastrointestinal cancer at time of diagnosis are associated with poor prognosis. The aim of this study is to evaluate the prognostic value of serum YKL-40 before surgery and during follow-up in hepatocellular carcinoma (HCC) patients receiving curative resection. METHODS: Serum YKL-40 levels were determined by enzyme-linked immunosorbent assay. Overall and recurrence-free survival (RFS) curves were constructed using the Kaplan-Meier method and compared by the log-rank test. A Cox proportional-hazards regression model was performed to identify independent prognostic factors. Median follow-up time was 35 months. RESULTS: Baseline serum YKL-40 was elevated in 56% of patients with HCC receiving curative resection. Patients with elevated serum YKL-40 had significantly shorter overall and RFS than patients with normal serum YKL-40 (P = 0.003 and P = 0.001, respectively). Multivariate Cox regression analyses indicated that baseline serum YKL-40 was an independent prognostic variable for overall and RFS [hazard ratio (HR) = 1.968, 95% confidence interval (CI): 1.093-3.543, P = 0.024; HR = 1.891, 95% CI: 1.106-3.232, P = 0.020; respectively]. After curative resection, high serum YKL-40 (log-transformed continuous variable) within 6 months predicted significantly poorer overall survival (HR = 3.003, 95% CI: 1.323-6.817, P = 0.009). CONCLUSIONS: This study indicated that serum YKL-40 was an independent prognostic factor for overall and RFS in HCC patients receiving curative resection. Serial monitoring of serum YKL-40 after curative resection may provide prognostic information.


Subject(s)
Adipokines/blood , Carcinoma, Hepatocellular/mortality , Lectins/blood , Liver Neoplasms/mortality , Adolescent , Adult , Aged , Biomarkers, Tumor/blood , Carcinoma, Hepatocellular/blood , Carcinoma, Hepatocellular/secondary , Carcinoma, Hepatocellular/surgery , Chitinase-3-Like Protein 1 , Enzyme-Linked Immunosorbent Assay , Female , Humans , Liver Neoplasms/blood , Liver Neoplasms/pathology , Liver Neoplasms/surgery , Male , Middle Aged , Neoplasm Recurrence, Local , Prognosis , Survival Rate , Young Adult
19.
Curr Pharm Biotechnol ; 23(9): 1168-1178, 2022.
Article in English | MEDLINE | ID: mdl-34792009

ABSTRACT

BACKGROUND: Mounting evidence has shown that Cyclin E1 (CCNE1) facilitates various carcinoma progression, but its function in lung adenocarcinoma (LUAD) remains unclear. OBJECTIVE: Our study aims to explore the significance of CCNE1 in clinical progression and study its biological functions in LUAD. METHODS: CCNE1 expressions in LUAD specimens and cells were detected through quantitative realtime polymerase chain reaction (qRT-RCR) and western blot. An immunohistochemistry technique was used to detect CCNE1 expression to explore its association with clinical parameters. The LUAD cells with stable knockdown of CCNE1 were constructed by small interfering RNA. The effect of CCNE1 on LUAD cells proliferation and apoptosis was evaluated through Cell Counting Kit-8 (CCK-8), colony formation, and Annexin V/propidium iodide (AV-PI) assays, respectively. The cell migration and invasion were evaluated by Wound-healing and Transwell assays, respectively. The xenograft and lung metastasis mouse models were introduced to analyze how CCNE1 knockdown affects tumor growth and tumor metastasis. RESULTS: CCNE1 expression was upregulated in LUAD tissue and cells. CCNE1 knockdown inhibited LUAD cellular malignant behavior in vitro and reduced tumor growth and metastasis in vivo. High expression of CCNE1 was correlated with big tumor size, cancer stage, lymph node metastasis, and poor prognosis. CONCLUSION: CCNE1 overexpression promotes LUAD growth, metastasis, and forebode poor prognosis: it can serve as a new prognostic marker of LUAD.


Subject(s)
Adenocarcinoma of Lung , Adenocarcinoma , Lung Neoplasms , Adenocarcinoma/genetics , Adenocarcinoma of Lung/genetics , Adenocarcinoma of Lung/metabolism , Adenocarcinoma of Lung/pathology , Animals , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Cyclin E/genetics , Cyclin E/metabolism , Gene Expression Regulation, Neoplastic , Humans , Lung Neoplasms/diagnosis , Lung Neoplasms/genetics , Mice , Oncogene Proteins/genetics , Oncogene Proteins/metabolism , Prognosis
20.
Polymers (Basel) ; 14(12)2022 Jun 14.
Article in English | MEDLINE | ID: mdl-35745984

ABSTRACT

Nutritional food supplements and pharmaceutical products produced with vitamin K2 as raw materials a very promising market in the global scope. The main production method of vitamin K2 is microbial fermentation, but approximately 50% of vitamin K2 synthesized by the main production strain Bacillus subtilis natto exists in extracellular form, which is not easy to separate and extract. In order to solve this problem, in this study, we synthesized a novel cellulose flocculant, MCC-g-LMA, by grafting reaction using microcrystalline cellulose (MCC) and lauryl methacrylate (LMA) as monomers, and ammonium persulfate as an initiator to flocculate VK2 from the fermentation supernatant. The flocculant was characterized by Fourier transform infrared spectroscopy (FTIR), elemental analysis, and scanning electron microscopy (SEM), and the grafting reaction was successful. When the flocculant dosage was 48.0 mg/L and pH was 5.0, the flocculation rate of the MCC-g-LMA on the fermentation supernatant reached 85.3%, and the enrichment rate of VK2 reached 90.0%. Furthermore, we explored the flocculation mechanism of VK2 by the MCC-g-LMA and speculated that the flocculation mechanism mainly included adsorption bridging, hydrophobic association and net trapping and sweep effect. In this study, the extraction method for trace high-value biological products in the fermentation supernatant was improved, which provided a method and theoretical basis for the efficient separation and purification of VK2 and other terpenoids.

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