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1.
Heliyon ; 10(19): e38831, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39435109

RESUMO

Patients with malignant tumors are prone to present hypercoagulability of blood and form thrombosis, and its pathogenesis is complex involving various factors from clinical and histopathological to genetic influences. Current studies on the potential mechanism of blood hypercoagulability in patients with malignant tumors focus on the following aspects but are not limited: (1) tumor cells release coagulant-promoting substances, (2) tumor cells interact with the fibrinolytic system, (3) tumor cell-mediated platelet activation, (4) tumor-associated complement activation, and (5) genetic factors and clinical factors. Especially, the pathogenesis of blood hypercoagulability is in-depth analyzed covering tumor cells' release of procoagulant substances, the interplay of cancer cells and fibrinolytic system, platelet activation mediated by cancer cells, cancer-associated complement activation, and the action of genetic and clinical factors. We review the pathogenesis of blood hypercoagulability in patients with malignant tumors, which will assist in the research and development of new drugs and providing theoretical support for the formulation of the best treatment plan for patients, to prolong the survival of patients.

2.
Sensors (Basel) ; 24(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39001077

RESUMO

The triboelectric nanogenerator (TENG), as a novel energy harvesting technology, has garnered widespread attention. As a relatively young field in nanogenerator research, investigations into various aspects of the TENG are still ongoing. This review summarizes the development and dissemination of the fundamental principles of triboelectricity generation. It outlines the evolution of triboelectricity principles, ranging from the fabrication of the first TENG to the selection of triboelectric materials and the confirmation of the electron cloud overlapping model. Furthermore, recent advancements in TENG application scenarios are discussed from four perspectives, along with the research progress in performance optimization through three primary approaches, highlighting their respective strengths and limitations. Finally, the paper addresses the major challenges hindering the practical application and widespread adoption of TENGs, while also providing insights into future developments. With continued research on the TENG, it is expected that these challenges can be overcome, paving the way for its extensive utilization in various real-world scenarios.

3.
Adv Mater ; : e2407395, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39044603

RESUMO

Implantable medical devices (IMDs), like pacemakers regulating heart rhythm or deep brain stimulators treating neurological disorders, revolutionize healthcare. However, limited battery life necessitates frequent surgeries for replacements. Ultrasound power transfer (UPT) emerges as a promising solution for sustainable IMD operation. Current research prioritizes implantable materials, with less emphasis on sound field analysis and maximizing energy transfer during wireless power delivery. This review addresses this gap. A comprehensive analysis of UPT technology, examining cutting-edge system designs, particularly in power supply and efficiency is provided. The review critically examines existing efficiency models, summarizing the key parameters influencing energy transmission in UPT systems. For the first time, an energy flow diagram of a general UPT system is proposed to offer insights into the overall functioning. Additionally, the review explores the development stages of UPT technology, showcasing representative designs and applications. The remaining challenges, future directions, and exciting opportunities associated with UPT are discussed. By highlighting the importance of sustainable IMDs with advanced functions like biosensing and closed-loop drug delivery, as well as UPT's potential, this review aims to inspire further research and advancements in this promising field.

4.
Langmuir ; 40(8): 4277-4284, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38360538

RESUMO

High load-bearing capacity is one of the crucial indicators for liquid superlubricants to move toward practicality. However, some of the current emerging systems not only have low contact pressures but also are highly susceptible to further degradation due to water adsorption and even superlubricity failure. Herein, a novel choline chloride-based ionic liquid analogues (ILAs) of a superlubricant with triethanolamine (TEOA) as the H-bond donor is reported for the first time; it obtains an ultralow coefficient of friction (0.005) and high load-bearing capacity (360 MPa, more than 2 times that of similar systems) due to adsorption of a small amount of water (<5 wt %) from the air. In situ Raman combined with 1H NMR and FTIR techniques reveals that adsorbed water competes with the hydroxyl group of TEOA for coordination with Cl-, leading to the conversion of some strong H-bonds to weak H-bonds in ILAs; the localized strong H-bonds and weak H-bonds endow the ILAs with high load-bearing capacity and the formation of ultralow shear-resistance sliding interfaces, respectively, under the shear motion. This study proposes a strategy to modulate the interactions between liquid species using adsorbed water from air as a competing ligand, which provides new insights into the design of ILA-based macroscopic liquid superlubricants with a high load-bearing capacity.

5.
Rev Sci Instrum ; 94(10)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37843420

RESUMO

A compact impact two-degree-of-freedom linear-rotary piezoelectric motor is proposed using a single actuator. The proposed piezoelectric actuator has a pair of deformation counteracting helical interdigitated electrodes on its outside surface, which can be divided into two parts. When the two parts of the piezoelectric actuator are driving under the same driving voltage signals, the motor can realize independent linear motion. When the two parts of the piezoelectric actuator are driving under the driving voltage signals with opposite duty cycles, the motor can realize independent rotary motion. The fabricated piezoelectric motor can produce a maximum average linear velocity of 1.9 and -2.3 mm/s with a saw-shaped driving signal of 400 Vp-p (peak-to-peak driving voltage) at 9 kHz. Experiments also show that the fabricated piezoelectric motor can realize a maximum average rotary velocity of 2440 and -2235 mrad/s with a driving signal of 400 Vp-p at 9 kHz. The maximum load force and torque of the prototype are about 0.4 N and 1.5 mN m, respectively. The proposed motor provides a wide driving frequency and realizes high velocity in both linear and rotary motions.

6.
Micromachines (Basel) ; 13(9)2022 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-36144033

RESUMO

The contact process of stator and slider described by the Coulomb friction model is basically in a pure sliding friction state, and a mechanical model based on the Dahl friction theory was proposed to describe the contact process between stator and slider of V-shape linear ultrasonic motor. With consideration for the tangential compliance of stator and slider, the dynamic contact and friction processes of stator and slider were addressed in stages. The simulation results show that the ratio of the friction positive work decreases with the increase of the preload, and the vibration amplitude of the stator increases the proportion of positive work of the friction force. Improving the contact stiffness of the stator and slider is conducive to improving the output performance of the ultrasonic motor. The asymmetry of the left and right performance of the V-shaped vibrator will cause a difference in the left and right running speeds of the ultrasonic motor. The improved Dahl friction-driving model makes up for the discontinuity of tangential contact force calculated by the Coulomb friction model. This study demonstrates that the friction-driving model based on the Dahl theory is reliable and reasonable for linear ultrasonic motors according to the experimental results.

7.
Materials (Basel) ; 15(6)2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35329474

RESUMO

Most studies on the corrosion inhibition performance of organic molecules and (nano)materials were conducted within "carbon steel/1.0 M HCl" solution system using similar experimental and theoretical methods. As such, the numerous research findings in this system are sufficient to conduct comparative studies to select the best-suited inhibitor type that generally refers to a type of inhibitor with low concentration/high inhibition efficiency, nontoxic properties, and a simple and cost-economic synthesis process. Before data collection, to help readers have a clear understanding of some crucial elements for the evaluation of corrosion inhibition performance, we introduced the mainstay of corrosion inhibitors studies involved, including the corrosion and inhibition mechanism of carbon steel/HCl solution systems, evaluation methods of corrosion inhibition efficiency, adsorption isotherm models, adsorption thermodynamic parameters QC calculations, MD/MC simulations, and the main characterization techniques used. In the classification and statistical analysis section, organic compounds or (nano)materials as corrosion inhibitors were classified into six types according to their molecular structural characteristics, molecular size, and compound source, including drug molecules, ionic liquids, surfactants, plant extracts, polymers, and polymeric nanoparticles. We outlined the important conclusions obtained from recent literature and listed the evaluation methods, characterization techniques, and contrastable experimental data of these types of inhibitors when used for carbon steel corrosion in 1.0 M HCl solution. Finally, statistical analysis was only performed based on these data from carbon steel/1.0 M HCl solution system, from which some conclusions can contribute to reducing the workload of the acquisition of useful information and provide some reference directions for the development of new corrosion inhibitors.

8.
Environ Sci Pollut Res Int ; 27(2): 2165-2183, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31773536

RESUMO

In this study, we evaluated atmospheric particulate matter (PM) concentration predictions at a regional scale using a simplified Lagrangian particle dispersion modeling system and the Bayesian and multiplicative ratio correction optimization (Bayesian-RAT) method to improve the mixing ratio forecast of PM10 and PM2.5. We first examined the forecast performance of the LPD (i.e., the simplified FLEXPART model combined with the Bayesian-RAT method) by comparing the model predictions with the PM concentration observations from 95 observation stations in Xingtai city and its surrounding areas. The first 2 months (i.e., Oct. and Nov. 2017) of the study period represented the typical spin-up time period, and the analysis period was December 2017. The LPD forecast system was much better (correlation coefficient: R=0.64 vs. 0.48 and 0.67 vs. 0.50 for PM10 and PM2.5, respectively; root mean square error: RMSE = 74.98 vs. 105.96 µg/m3 for PM10 and 54.89 vs. 72.81 µg/m3 for PM2.5) than the pre-calibration results. We also compared the LPD forecasting model with other models (WRF-Chem and Camx) using data from monitoring stations in Xingtai, China, and the LPD forecasting model had higher accuracy than the other models. In particular, the RMSE scores for hourly PM10 concentrations were reduced by 36.51% and 42.21% compared to WRF-Chem and to Camx, respectively. The PM2.5 forecast results, as in the case of PM10, showed a better performance when applying the LPD model to the data from the monitoring stations. The RMSE was reduced by 26.44% and 18.47% relative to the WRF-Chem and Camx, respectively. The results confirm that there is much advantage of the LPD forecast system for predicting PM and may be for other pollutants.


Assuntos
Poluentes Atmosféricos/análise , Teorema de Bayes , Material Particulado/análise , China , Cidades , Monitoramento Ambiental , Previsões , Tamanho da Partícula
9.
Virchows Arch ; 442(1): 39-47, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12536313

RESUMO

We examined regeneration and fibrosis in the necrotic areas of hepatic stellate cells (HSCs). Acute hepatic injury was induced in rats by administration of an intraperitoneal injection of high-dose dimethylnitrosamine (50 mg/kg body weight). Liver samples were obtained from rats 6, 12, 24, 36 h and 2, 3, 5, 7, 10, and 14 days after the injection. They were examined by light and electron microscopy and by immunohistochemical methods. Hemorrhagic necrosis became most prominent 36 h after treatment and extended into zones 3 and 2. In the submassive necrotic areas the sinusoidal structure was destroyed. No HSCs positive for alpha-smooth muscle actin or desmin were present. On day 5, when necrotic tissues were almost removed by infiltrating macrophages, HSCs strongly positive for alpha-smooth muscle actin and desmin appeared along the surface of the preserved parenchyma and migrated into the necrotic areas along the residual reticulin fibers. By day 14 most of the necrotic areas were almost completely replaced by the regeneration of hepatocytes and central to central (C-C) bridging fibrosis. Our results indicate that following submassive complete necrosis, HSCs in the preserved liver parenchyma have roles in the formation of sinusoidal wall for remodeling in necrotic areas via their activation, proliferation, and migration into the necrotic areas.


Assuntos
Dimetilnitrosamina , Hemorragia/patologia , Cirrose Hepática Experimental/patologia , Regeneração Hepática , Fígado/ultraestrutura , Actinas/metabolismo , Animais , Divisão Celular , Movimento Celular , Desmina/metabolismo , Dimetilnitrosamina/administração & dosagem , Modelos Animais de Doenças , Hemorragia/etiologia , Injeções Intraperitoneais , Células de Kupffer/efeitos dos fármacos , Células de Kupffer/metabolismo , Células de Kupffer/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Cirrose Hepática Experimental/complicações , Cirrose Hepática Experimental/metabolismo , Masculino , Necrose , Ratos , Ratos Wistar
10.
Oncol Rep ; 10(1): 207-11, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12469170

RESUMO

Prostate cancer is one of the most common age-related malignancies. The occurrence frequency of prostate cancer is very different according to prostate zones. The prostate stroma is an important element in growth and differentiation of the normal prostate and also has a close relationship to the occurrence of benign prostatic hypertrophy and cancer. We examined 14 cases of normal prostate tissues obtained at autopsy and 11 cases of prostate cancer tissues at radical prostatectomy specimens with cancers for clarifying the characteristics of stromal components in the normal prostate and the correlation between the stroma and the occurrence of prostate cancers. Stromal cells, such as smooth muscle cells, myofibroblasts and fibroblasts were identified by immunohistochemistry (IHC). Connective tissue fibers were detected by Elastica van Gieson and also IHC stain. Quantitative analysis of the smooth muscle tissue and connective tissue fibers were performed using a computer image analyzer system. In the normal prostate, stromal components varied in each zone. Every zone of the prostate contained smooth muscle cells, myofibroblasts, fibroblasts and collagen fibers. Elastic fibers were clearly visible in the transition zone. Smooth muscle cells were the main stromal component but less numerous in the frequent occurrence zone (peripheral zone) of prostate cancer (p<0.05). Myofibroblasts and fibroblasts were found either in normal or cancer tissues, although a few in number. The increase of collagen fibers accompanied decrease of smooth muscle cells as prostate cancer grade increased (p<0.05). The characteristics of stromal components and their amounts in the normal prostate appear to correlate with a distinct predilection for cancer occurrence in the peripheral zone and a weak stromal reaction in prostate cancers.


Assuntos
Hiperplasia Prostática/patologia , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/patologia , Células Estromais/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular , Fibroblastos/patologia , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Mioblastos/patologia , Miócitos de Músculo Liso/patologia , Estadiamento de Neoplasias , Fenótipo , Próstata/citologia , Próstata/metabolismo , Prostatectomia , Doenças Prostáticas/patologia
11.
Pathol Int ; 52(1): 25-30, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11940203

RESUMO

To elucidate the roles of CD34-positive stromal cells and alpha-smooth muscle actin-positive stromal cells at the tumor border of skin sweat gland neoplasms, we examined expression of stromal cell markers in the tumor capsule of 19 skin sweat gland neoplasms (16 mixed tumors of the skin and three nodular hidradenomas) using monoclonal antibodies to CD34, CD31, cytokeratin 14 (CK14), alpha-smooth muscle actin (ASMA) and high molecular weight caldesmon (HCD). We regarded CD34-positive, CD31-, CK14-, ASMA- and HCD-negative stromal cells to be CD34-positive stromal cells, and ASMA-positive, HCD-, CK14-, CD34- and CD31-negative stromal cells to be ASMA-positive stromal cells. CD34-positive stromal cells were detected in the tumor capsule of all 19 of the tumors examined. In nine of the 16 mixed tumors (56%) and all of the three nodular hidradenomas, ASMA-positive stromal cells were detected at the immediate inner side of the CD34-positive stromal cell layers. These results indicate that cellular components in the tumor capsules of mixed tumors of the skin and nodular hidradenomas are CD34-positive stromal cells and ASMA-positive stromal cells, and suggest that stromal cells of these two cell types are associated with tumor capsule formation of skin sweat gland neoplasms.


Assuntos
Actinas/análise , Antígenos CD34/análise , Pele/patologia , Neoplasias das Glândulas Sudoríparas/patologia , Humanos , Imuno-Histoquímica , Músculo Liso/química , Pele/química , Células Estromais/química , Células Estromais/patologia , Neoplasias das Glândulas Sudoríparas/metabolismo
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