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1.
Lasers Med Sci ; 39(1): 41, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38240851

RESUMEN

Far infrared (FIR) irradiation is commonly used as a convenient, non-contact, non-invasive treatment for diseases such as myocardial ischemia, diabetes, and chronic kidney disease. In this review, we focus on reviewing the potential therapeutic mechanisms of FIR and its cutting-edge applications in cancer detection. Firstly, we searched the relevant literature in the last decade for systematic screening and briefly summarized the biophysical properties of FIR. We then focused on the possible mechanisms of FIR in wound healing, cardiovascular diseases, and other chronic diseases. In addition, we review recent applications of FIR in cancer detection, where Fourier transform infrared spectroscopy and infrared thermography provide additional diagnostic methods for the medical diagnosis of cancer. Finally, we conclude and look into the future development of FIR for disease treatment and cancer detection. As a high-frequency non-ionizing wave, FIR has the advantages of safety, convenience, and low cost. We hope that this review can provide biological information reference and relevant data support for those who are interested in FIR and related high-frequency non-ionizing waves, to promote the further application of FIR in the biomedical field.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedad de la Arteria Coronaria , Neoplasias , Insuficiencia Renal Crónica , Humanos , Rayos Infrarrojos , Cicatrización de Heridas/efectos de la radiación , Neoplasias/diagnóstico , Neoplasias/terapia
2.
Sensors (Basel) ; 24(5)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38474906

RESUMEN

This paper proposes a wind-speed-adaptive resonant piezoelectric energy harvester for offshore wind energy collection (A-PEH). The device incorporates a coil spring structure, which sets the maximum threshold of the output rotational frequency, allowing the A-PEH to maintain a stable output rotational frequency over a broader range of wind speeds. When the maximum output excitation frequency of the A-PEH falls within the sub-resonant range of the piezoelectric beam, the device becomes wind-speed-adaptive, enabling it to operate in a sub-resonant state over a wider range of wind speeds. Offshore winds exhibit an annual average speed exceeding 5.5 m/s with significant variability. Drawing from the characteristics of offshore winds, a prototype of the A-PEH was fabricated. The experimental findings reveal that in wind speed environments, the device has a startup wind speed of 4 m/s, and operates in a sub-resonant state when the wind speed exceeds 6 m/s. At this point, the A-PEH achieves a maximum open-circuit voltage of 40 V and an average power of 0.64 mW. The wind-speed-adaptive capability of the A-PEH enhances its ability to harness offshore wind energy, showcasing its potential applications in offshore wind environments.

3.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(3): 439-446, 2024 Jun 25.
Artículo en Zh | MEDLINE | ID: mdl-38932528

RESUMEN

Electrical impedance tomography (EIT) is a non-radiation, non-invasive visual diagnostic technique. In order to improve the imaging resolution and the removing artifacts capability of the reconstruction algorithms for electrical impedance imaging in human-chest models, the HMANN algorithm was proposed using the Hadamard product to optimize multilayer artificial neural networks (MANN). The reconstructed images of the HMANN algorithm were compared with those of the generalized vector sampled pattern matching (GVSPM) algorithm, truncated singular value decomposition (TSVD) algorithm, backpropagation (BP) neural network algorithm, and traditional MANN algorithm. The simulation results showed that the correlation coefficient of the reconstructed images obtained by the HMANN algorithm was increased by 17.30% in the circular cross-section models compared with the MANN algorithm. It was increased by 13.98% in the lung cross-section models. In the lung cross-section models, some of the correlation coefficients obtained by the HMANN algorithm would decrease. Nevertheless, the HMANN algorithm retained the image information of the MANN algorithm in all models, and the HMANN algorithm had fewer artifacts in the reconstructed images. The distinguishability between the objects and the background was better compared with the traditional MANN algorithm. The algorithm could improve the correlation coefficient of the reconstructed images, and effectively remove the artifacts, which provides a new direction to effectively improve the quality of the reconstructed images for EIT.


Asunto(s)
Algoritmos , Impedancia Eléctrica , Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Tórax , Tomografía , Humanos , Tomografía/métodos , Tórax/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Pulmón/diagnóstico por imagen , Pulmón/fisiología
4.
Phys Rev Lett ; 131(26): 260201, 2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38215365

RESUMEN

Non-Hermitian (NH) extension of quantum-mechanical Hamiltonians represents one of the most significant advancements in physics. During the past two decades, numerous captivating NH phenomena have been revealed and demonstrated, but all of which can appear in both quantum and classical systems. This leads to the fundamental question: what NH signature presents a radical departure from classical physics? The solution of this problem is indispensable for exploring genuine NH quantum mechanics, but remains experimentally untouched so far. Here, we resolve this basic issue by unveiling distinct exceptional entanglement phenomena, exemplified by an entanglement transition, occurring at the exceptional point of NH interacting quantum systems. We illustrate and demonstrate such purely quantum-mechanical NH effects with a naturally dissipative light-matter system, engineered in a circuit quantum electrodynamics architecture. Our results lay the foundation for studies of genuinely quantum-mechanical NH physics, signified by exceptional-point-enabled entanglement behaviors.

5.
Opt Lett ; 47(2): 421-424, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-35030620

RESUMEN

We demonstrate a new, to the best of our knowledge, kind of self-pulsation in a microcavity Brillouin laser. This specific self-pulsation is generated by the interplay between the Brillouin lasing and the thermo-optic effect in an optical microcavity. Intriguingly, the self-pulsation behaviors are simultaneously present in both forward input pump and backward Brillouin lasing emission. By developing a coupled-mode theory, our numerical simulations display an excellent agreement with the experimental results.

6.
Opt Lett ; 47(7): 1638-1641, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35363697

RESUMEN

We realize a chip-based Brillouin microlaser with remarkable features of high power and low noise using a microtoroid resonator. Our Brillouin microlaser is able to output a power of up to 126 mW with a fundamental linewidth down to 245 mHz. Additionally, in the course of Brillouin lasing we observe an intriguing power saturation-like effect, which can be attributed to complex thermo-optic-effect-induced mode mismatch between the pump and Brillouin modes. To have a quantitative understanding of this phenomenon, we develop a model by simultaneously considering Brillouin lasing and the thermo-optic effect occurring in the microcavity. Of importance, our theoretical results match well with experimentally measured data.

7.
Sensors (Basel) ; 22(13)2022 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-35808329

RESUMEN

Air velocity of coal mine ventilation is an important consideration that may cause serious damage. This paper proposes a simple, low cost and effective air velocity monitor (AVM) for coal mine ventilation. The AVM uses the lock-in characteristic of vortex-induced vibration (VIV) to sense the air velocity. Amplitude of the VIV is converted into frequency signal of a vortex-induced triboelectric nanogenerator (VI-TENG) to improve the durability. Structure of the AVM are designed, and parameters of the AVM are optimized with experiments. For the upper and lower air velocity thresholds of 3.1 and 3.6 m/s, the optimized flexible beam length, slider weight, electrode space and electrode width are 42.5 mm, 0.4 g, 0.2 mm and 0.5 mm, respectively. Experiments also show that the output frequency of the VI-TENG could represent the amplitude of VIV well with the correlation coefficient of 0.93. Durability test demonstrates that the AVM generates stable output frequency in 120,000 cycles. A prototype and its controller are fabricated. Wind tunnel tests of this prototype show that it can give alarm when the gas velocity goes above the upper threshold or below the lower threshold. The proposed AVM could be a good solution for simple and effective coal mine ventilation alarm.


Asunto(s)
Movimientos del Aire , Minería , Ventilación , Carbón Mineral , Electrodos , Gases/análisis , Nanotecnología , Vibración
8.
Sensors (Basel) ; 21(4)2021 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-33670072

RESUMEN

A quantitative and rapid burn injury detection method has been proposed based on the electrical impedance spectroscopy (EIS) of blood with a seven-parameter equivalent circuit. The degree of burn injury is estimated from the electrical impedance characteristics of blood with different volume proportions of red blood cells (RBCs) and heated red blood cells (HRBCs). A quantitative relationship between the volume portion HHCT of HRBCs and the electrical impedance characteristics of blood has been demonstrated. A seven -parameter equivalent circuit is employed to quantify the relationship from the perspective of electricity. Additionally, the traditional Hanai equation has been modified to verify the experimental results. Results show that the imaginary part of impedance ZImt under the characteristic frequency (fc) has a linear relationship with HHCT which could be described by ZImt = -2.56HHCT - 2.01 with a correlation coefficient of 0.96. Moreover, the relationship between the plasma resistance Rp and HHCT is obtained as Rp = -7.2HHCT + 3.91 with a correlation coefficient of 0.96 from the seven -parameter equivalent circuit. This study shows the feasibility of EIS in the quantitative detection of burn injury by the quantitative parameters ZImt and Rp, which might be meaningful for the follow-up clinical treatment for burn injury.


Asunto(s)
Quemaduras , Espectroscopía Dieléctrica , Impedancia Eléctrica , Quemaduras/diagnóstico , Eritrocitos , Humanos
9.
Opt Express ; 28(6): 7906-7916, 2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-32225425

RESUMEN

Whispering-gallery-mode optical microresonators have found impactful applications in various areas due to their remarkable properties such as ultra-high quality factor (Q-factor), small mode volume, and strong evanescent field. Among these applications, controllable tuning of the optical Q-factor is vital for on-chip optical modulation and various opto-electronic devices. Here, we report an experimental demonstration with a hybrid structure formed by an ultra-high-Q microtoroid cavity and a graphene monolayer. Thanks to the strong interaction of the evanescent wave with the graphene, the structure allows the Q-factor to be controllably varied in the range of 3.9 × 105 ∼ 6.2 × 107 by engineering optical absorption via changing the gap distance in between. At the same time, a resonant wavelength shift of 32 pm was also observed. Besides, the scheme enables us to approach the critical coupling with a coupling depth of 99.6%. As potential applications in integrated opto-electronic devices, we further use the system to realize a tunable optical filter with tunable bandwidth from 116.5 MHz to 2.2 GHz as well as an optical switch with a maximal extinction ratio of 31 dB and response time of 21 ms.

10.
Phys Rev Lett ; 123(19): 193604, 2019 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-31765185

RESUMEN

Non-Hermitian optical systems with parity-time (PT) symmetry have recently revealed many intriguing prospects that outperform conservative structures. The previous works are mostly rooted in complex arrangements with controlled gain-loss interplay. Here, we demonstrate anti-PT symmetry inherent in the nonlinear optical interaction based upon forward optical four-wave mixing in a laser-cooled atomic ensemble with negligible linear gain and loss. We observe that the pair of frequency modes undergo a nontrivial anti-PT phase transition between coherent power oscillation and optical parametric amplification in presence of a large phase mismatch.

11.
Sensors (Basel) ; 19(5)2019 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-30836669

RESUMEN

The aggregation of red blood cells (RBCs) in normal blood (non-coagulation) has been quantitatively measured by blood pulsatile flow based on multiple-frequency electrical impedance spectroscopy. The relaxation frequencies fc under static and flowing conditions of blood pulsatile flow are utilized to evaluate the RBC aggregation quantitatively with the consideration of blood flow factors (RBC orientation, deformation, thickness of electrical double layer (EDL)). Both porcine blood and bovine blood are investigated in experiments, for the reason that porcine blood easily forms RBC aggregates, while bovine blood does not. The results show that the relaxation frequencies fc of porcine blood and bovine blood present opposite performance, which indicates that the proposed relaxation frequency fc is efficient to measure RBCs aggregation. Furthermore, the modified Hanai equation is proposed to quantitatively calculate the influence of RBCs aggregation on relaxation frequency fc. The study confirms the feasibility of a high speed, on-line RBC aggregation sensing method in extracorporeal circulation systems.


Asunto(s)
Eritrocitos/fisiología , Animales , Bovinos , Agregación Celular/fisiología , Espectroscopía Dieléctrica , Impedancia Eléctrica , Agregación Eritrocitaria/fisiología , Humanos , Porcinos
12.
IEEE Trans Biomed Eng ; 71(8): 2432-2441, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38457328

RESUMEN

OBJECTIVE: Minimally invasive ultrasound ablation transducers have been widely studied. However, conventional designs are limited by the single working frequency, restricting their conformal ablation ability (i.e., ablation size and shape controllability). METHODS: New multi-frequency ultrasonic transducer design method is proposed based on the asymmetric backing layer, which divides the transducer into non-backing-layer region (i.e., front-piezoelectric region) and backing-layer region (i.e., front-piezoelectric-backing region) with multiple local thickness mode resonant frequencies. Ablation zone can be controlled by exciting the local resonance within or between the regions, and its control flexibility is further enhanced by driven under a frequency modulation signal. Experiments and calculations are combined for verifying the proposal. RESULTS: The fabricated transducer with a Y-direction asymmetric backing layer shows five resonances, with two in each region and one resonance excited in both regions. Spatial ultrasound emission is demonstrated by acoustic measurements. Tissue ablation experiments verified spatial ablation zone control, and frequency modulation driving method enables the spatial transition of ablation zone from one region to the other, generating different ablation sizes and shapes. Finally, patient-specific simulations verified the effectiveness of conformal ablation. CONCLUSION: The proposed transducer enables flexible control of ablation zone. SIGNIFICANCE: This study demonstrates a new method for conformal tumor ablation.


Asunto(s)
Diseño de Equipo , Transductores , Humanos , Neoplasias/cirugía , Neoplasias/diagnóstico por imagen , Animales
13.
Micromachines (Basel) ; 15(3)2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38542561

RESUMEN

Triboelectric nanogenerators (TENGs) can effectively collect low-frequency, disordered mechanical energy and are therefore widely studied in the field of ocean energy collection. Most of the rotary TENGs studied so far tend to have insufficient rotation, resulting in slow charge transfer rates in low-frequency ocean environments. For this reason, in this paper, we propose a wind-wave synergistic triboelectric nanogenerator (WWS-TENG). It is different from the traditional rotary TENGs based on free-standing mode in that its power generation unit has two types of rotors, and the two rotors rotate in opposite directions under the action of wind energy and wave energy, respectively. This type of exercise can more effectively collect energy. The WWS-TENG has demonstrated excellent performance in sea wind and wave energy harvesting. In the simulated ocean environment, the peak power can reach 13.5 mW under simulated wind-wave superposition excitation; the output of the WWS-TENG increased by 49% compared to single-wave power generation. The WWS-TENG proposal provides a novel means of developing marine renewable energy, and it also demonstrates broad application potential in the field of the self-powered marine Internet of Things (IoT).

14.
ACS Appl Mater Interfaces ; 16(1): 569-575, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38108825

RESUMEN

The water flow energy of rivers is an important renewable and clean energy that plays a vital role in human life but is challenging to harvest at low flow velocity. This work proposes a bionic fish-shaped triboelectric-electromagnetic hybrid generator (BF-TEHG) via a two-stage swing mechanism for harvesting water flow energy. It is designed to simulate the shape of fish, effectively improving its ability to utilize low-velocity water flow energy and enabling it to operate at a minimum flow rate of 0.24 m/s. Furthermore, the impact of motion parameters on electrical performance is studied. The triboelectric and electromagnetic power-generation units can generate peak powers of 0.55 and 0.34 mW in the simulated river environments with a flow velocity of 0.98 m/s. In applications, after being immersed in water for 40 days, the BF-TEHG maintains its electrical performance without reduction, indicating excellent water immersion durability. Therefore, this work proposes an efficient strategy to harvest low-velocity water flow energy and provides an acceptable candidate for monitoring water flow conditions.

15.
J Transl Med ; 11: 300, 2013 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-24314011

RESUMEN

BACKGROUND: Heat shock proteins (HSPs) are capable of promoting antigen presentation of chaperoned peptides through interactions with receptors on antigen presenting cells. This property of HSPs suggests a potential function as an adjuvant-free carrier to stimulate immune responses against a covalently linked fusion partner. MAGE-A1 is a likely candidate for tumor immunotherapy due to its abundant immunogenic epitopes and strict tumor specificity. To analyze the influence of HSP70 conjugation to MAGE-A1, towards developing a novel effective vaccine against MAGE-expressing tumors, we cloned the murine counterpart of the human HSP70 and MAGE-A1 genes. METHODS: Recombinant proteins expressing Mage-a1 (aa 118-219), Hsp70, and Mage-a1-Hsp70 fusion were purified and used to immunize C57BL/6 mice. The humoral and cellular responses elicited against Mage-a1 were measured by ELISA, IFN-γ ELISPOT assay, and cytotoxicity assay. RESULTS: Immunization of mice with Mage-a1-Hsp70 fusion protein elicited significantly higher Mage-a1-specific antibody titers than immunization with either Mage-a1 alone or a combination of Mage-a1+Hsp70. The frequency of IFN-γ-producing cells and the cytotoxic T lymphocyte (CTL) activity was also elevated. Consistent with the elevated immune response, immunization with fusion protein induced potent in vivo antitumor immunity against MAGE-a1-expressing tumors. CONCLUSIONS: These results indicate that the fusion of Hsp70 to Mage-a1 can enhance immune responses and anti-tumor effects against Mage-a1-expressing tumors. Fusion of HSP70 to a tumor antigen may greatly enhance the potency of protein vaccines and can potentially be applied to other cancer systems with known tumor-specific antigens. These findings provide a scientific basis for the development of a novel HSP70 and MAGE fusion protein vaccine against MAGE-expressing tumors.


Asunto(s)
Vacunas contra el Cáncer/inmunología , Proteínas HSP70 de Choque Térmico/genética , Melanoma Experimental/inmunología , Proteínas de Neoplasias/genética , Potencia de la Vacuna , Animales , Formación de Anticuerpos , Vacunas contra el Cáncer/genética , Ensayo de Inmunoadsorción Enzimática , Femenino , Proteínas HSP70 de Choque Térmico/inmunología , Humanos , Melanoma Experimental/terapia , Ratones , Ratones Endogámicos C57BL , Proteínas de Neoplasias/inmunología
16.
Opt Lett ; 38(13): 2171-3, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23811867

RESUMEN

We examine the photon statistics of photon-subtracted thermal light using photon-number-resolved detection. We demonstrate experimentally that the photon number distribution transforms from a Bose-Einstein distribution to a Poisson distribution as the number of subtracted photons increases. We also show that second- and higher-order photon correlation functions can be directly determined from the photon-number-resolved detection measurements of a single optical beam.

17.
Zhonghua Bing Li Xue Za Zhi ; 42(12): 806-9, 2013 Dec.
Artículo en Zh | MEDLINE | ID: mdl-24507097

RESUMEN

OBJECTIVE: To explore the expression and diagnostic significance of glypican-3 (GPC3) in hepatoblastoma. METHODS: Five tissue microarray paraffin blocks were constructed to include 54 cases of hepatoblastoma. The tumor tissue samples were obtained from 3 surgical biopsies, 33 needle biopsies, 5 stage I resection tumors, and 13 stage II resection tumors after transcatheter arterial chemoembolization. Ten samples of non-neoplastic hepatic tissue adjacent to tumor were used as control. Immunohistochemical staining of GPC3 (clone 1G12) was performed. Among the 54 cases of hepatoblastoma, 22 cases were fetal subtype, 24 cases were mixed fetal and embryonal subtype and 8 cases were mixed epithelial and mesenchymal type. RESULTS: GPC3 was positive in fetal epithelial cells (54/54, 100%), but negative or weakly positive in embryonic epithelial cells in all cases of hepatoblastoma. Undifferentiated small cells and all mesenchymal components were negative for the expression. Non-neoplastic hepatocytes adjacent to tumor were negative for GPC3 expression (0/10) . CONCLUSIONS: Fetal epithelial components of hepatoblastoma express GPC3 protein detectable by immunohistochemistry. Normal hepatocytes after birth, small cell undifferentiated and embryonic epithelial components of hepatoblastoma do not or weakly express GPC3 protein. Therefore, GPC3 immunohistochemistry offers a valuable aid to the diagnosis of hepatoblastoma in infants and children.


Asunto(s)
Glipicanos/metabolismo , Hepatoblastoma/diagnóstico , Neoplasias Hepáticas/diagnóstico , Niño , Preescolar , Diagnóstico Diferencial , Células Epiteliales/metabolismo , Femenino , Hepatoblastoma/metabolismo , Hepatoblastoma/patología , Humanos , Inmunohistoquímica , Lactante , Recién Nacido , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino
18.
Materials (Basel) ; 16(13)2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37445056

RESUMEN

Two-dimensional Cu2FeSnS4 (CFTS) nanosheets with exposed high-energy facets (111) have been synthesized by a facile, scalable, and cost-effective one-pot heating process. The CFTS phase formation is confirmed by both X-ray diffraction and Raman spectroscopy. The formation mechanism of exposed high-energy facet CFTS growth is proposed and its electrochemical and photoelectrochemical properties are investigated in detail to reveal the origin of the anisotropic effect of the high-energy facets. Dye-sensitized solar cells (DSSC) achieve a favorable power conversion efficiency of 5.92% when employing CFTS thin film as a counter electrode, suggesting its potential as a cost-effective substitute for Pt in DSSCs.

19.
Opt Express ; 20(22): 24124-31, 2012 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-23187175

RESUMEN

We report an experimental demonstration of optimal storage and retrieval of heralded single-photon wave packets using electromagnetically induced transparency (EIT) in cold atoms at a high optical depth. We obtain an optimal storage efficiency of (49 ± 3)% for single-photon waveforms with a temporal likeness of 96%. Our result brings the EIT quantum light-matter interface closer to practical quantum information applications.

20.
Opt Lett ; 37(4): 689-91, 2012 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-22344149

RESUMEN

We demonstrate the fractional second-harmonic (SH) Talbot effect in a hexagonally poled LiTaO3 crystal. We carefully record the SH Talbot images at 1/2, 1/3, and 1/4 Talbot lengths, which are well matched with the simulated images by using the modified Rayleigh-Sommerfeld diffraction formula. A simplified model with a hexagonal array is adopted in the simulations. Also, we use a modified reciprocal vector theory to analytically explain the evolution of the SH array at fractional Talbot lengths. Our results show that the images are sensitive to the duty circle and the background of the array.

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