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1.
Opt Lett ; 49(18): 5328-5331, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39270297

RESUMEN

Metamaterials have opened up a new field of electromagnetic wave stealth that can achieve cross-band electromagnetic wave stealth through high electromagnetic wave absorption and low infrared emission. However, traditional cross-band stealth metamaterials make covering the terahertz band challenging and have certain design flaws. This Letter introduces an innovative cross-band electromagnetic wave stealth metasurface design that can achieve cross-band stealth in the infrared, microwave, and THz bands. We use phase change materials and the gradient principle to achieve GHz and THz cross-band absorption. We also design surface height-covered low infrared emitting materials, which give them lower infrared emissivity. These functions give it enormous potential in military applications, and using phase change materials for cross-band absorption also provides new, to our knowledge, ideas for multifunctional stealth materials.

2.
BMC Palliat Care ; 23(1): 222, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39244530

RESUMEN

BACKGROUND: Breakthrough cancer pain (BTcP) has a negative impact on patients' quality of life, general activities, and is related to worse clinical outcomes. Fentanyl inhalant is a hand-held combination drug-device delivery system providing rapid, multi-dose (25µg/dose) administration of fentanyl via inhalation of a thermally generated aerosol. This multicenter, randomized, placebo-controlled, multiple-crossover, double-blind study evaluated the efficacy, safety, and tolerability of fentanyl inhalant in treating BTcP in opioid-tolerant patients. METHODS: The trial was conducted in opioid-tolerant cancer patients with 1 ~ 4 BTcP outbursts per day. Each patient was treated and observed for 6 episodes of BTcP (4 with fentanyl inhalant, 2 with placebo). During each episode of targeted BTcP, patients were allowed up to six inhalations, with an interval of at least 4 min between doses. Primary outcome was the time-weighted sum of PID (pain intensity difference) scores at 30 min (SPID30). RESULTS: A total of 335 BTcP episodes in 59 patients were treated. The mean SPID30 was -97.4 ± 48.43 for fentanyl inhalant-treated episodes, and -64.6 ± 40.25 for placebo-treated episodes (p < 0.001). Significant differences in PID for episodes treated with fentanyl inhalant versus placebo was seen as early as 4 min and maintained for up to 60 min. The percentage of episodes reported PI (pain intensity) scores ≤ 3, a ≥ 33% or ≥ 50% reduction in PI scores at 30 min, PR30 (pain relief scores at 30 min) and SPID60 favored fentanyl inhalant over placebo. Only 4.4% of BTcP episodes required rescue medication in fentanyl inhalant group. Most AEs were of mild or moderate severity and typical of opioid drugs. CONCLUSION: Treatment with fentanyl inhalant was shown to be a promising therapeutic option for BTcP, with significant pain relief starting very soon after dosing. Confirmation of effectiveness requires a larger phase III trial. TRIAL REGISTRATION: ClinicalTrials.gov: NCT05531422 registered on 6 September 2022 after major amendment, NCT04713189 registered on 14 January 2021.


Asunto(s)
Analgésicos Opioides , Dolor Irruptivo , Dolor en Cáncer , Fentanilo , Humanos , Fentanilo/uso terapéutico , Fentanilo/farmacología , Fentanilo/administración & dosificación , Método Doble Ciego , Masculino , Persona de Mediana Edad , Femenino , Analgésicos Opioides/uso terapéutico , Analgésicos Opioides/administración & dosificación , Dolor Irruptivo/tratamiento farmacológico , Dolor Irruptivo/etiología , Anciano , Dolor en Cáncer/tratamiento farmacológico , Adulto , Administración por Inhalación , Estudios Cruzados , Dimensión del Dolor/métodos , Resultado del Tratamiento , Anciano de 80 o más Años
3.
Cancer Cell Int ; 23(1): 282, 2023 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-37981709

RESUMEN

Hsa_circ_0022383 (circ_0022383) is a newly discovered circRNA. Its functions and relevant molecular mechanisms in tumorigenesis have not been reported. Here we aimed to explore how circ_0022383 regulates the tumorigenesis of non-small-cell lung cancer (NSCLC). We found thatcirc_0022383 expression was dramatically elevated in NSCLC tissues and cell lines. Upregulation of circ_0022383 was associated with poor prognosis in NSCLC patients. Silencing of circ_0022383 repressed cell proliferation and migration in vitro and inhibited oncogenesis and tumor metastasis in vivo. Moreover, our results discovered that circ_0022383 was mainly located in the cytoplasm of NSCLC cells. Mechanistically, circ_0022383 sponged miR-495-3p to modulate KPNA2 expression, thereby regulating NSCLC tumorigenesis and progression. In conclusion, our study demonstrates that circ_0022383 facilitates NSCLC tumorigenesis by regulating the miR-495-3p/KPNA2 axis, providing new insights into NSCLC development.

4.
Prev Med ; 173: 107568, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37286092

RESUMEN

It has been discovered that some circular RNAs can serve as excellent therapeutic targets for breast cancer (BC). However, the biological role that circ ATAD3B plays in BC is not yet completely understood. As a result, the purpose of this work was to evaluate the function of circ_ATAD3B in the development of BC. Three different GEO datasets were used to compile the expression profiles of circRNAs related to BC (GSE101124, GSE165884, and GSE182471). CCK-8 and the production of clones, in addition to RT-PCR and western blot assays, were utilized in this study to evaluate the regulation of these three biological molecules in the process of BC carcinogenesis.circ_ATAD3B was the only potential BC-related circRNA that was significantly reduced in BC tumor tissues, and it functioned as a miR-570-3p sponge to suppress cell survival and proliferation, as stated by the aforementioned two algorithms. The expression of MX2 was boosted when circ_ATAD3B was used to sponge miR-570-3p. The inhibitory effect that circ_ATAD3B has on the malignant phenotype of BC cells was overcome by the expression of miR-570-3p through up-regulation and MX2 through down-regulation. The tumor suppressor circ_ATAD3B prevents cancer progression by regulating the miR-570-3p/MX2 pathway. Circ_ATAD3B may be a candidate for targeted therapy of breast cancer.


Asunto(s)
Neoplasias de la Mama , MicroARNs , Humanos , Femenino , Neoplasias de la Mama/genética , Proliferación Celular/genética , Algoritmos , Fenotipo , MicroARNs/genética , ATPasas Asociadas con Actividades Celulares Diversas/genética , Proteínas de la Membrana , Proteínas Mitocondriales , Proteínas de Resistencia a Mixovirus
5.
Appl Opt ; 62(2): 266-274, 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36630224

RESUMEN

Due to the occurrence of redundant speckle, multimode fiber (MMF) imaging is extremely challenging. Our work studies the relationship between the effective feature distribution of the speckle field and the local spatial position and area, and proves that the information distribution of the speckle is highly redundant. The effective feature refers to the phase and amplitude information of the optical field carrying the image point information and the co-exciting very redundant information due to mode dispersion, interference, coupling, and entrained noise through transmission. The neural network Swin-Unet can well learn the association information between global and local features, greatly simplifies the fitting of the MMF end-to-end global mapping relationship, and achieves high-fidelity reconstruction from the local speckle field to the global image. This work will contribute to the realization of MMF real-time large-field endoscopic imaging.

6.
Opt Express ; 30(4): 5657-5672, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35209523

RESUMEN

An improved deep neural network incorporating attention mechanism and DSSIM loss function (AM_U_Net) is used to recover input images with speckles transmitted through a multimode fiber (MMF). The network is trained on a relatively small dataset and demonstrates an optimal reconstruction ability and generalization ability. Furthermore, a bimodal fusion method is developed based on S polarization and P polarization speckles, greatly improving the recognition accuracy. These findings prove that AM_U_Net has remarkable capabilities for information recovery and transfer learning and good tolerance and robustness under different MMF transmission conditions, indicating its significant application potential in medical imaging and secure communication.


Asunto(s)
Aprendizaje Profundo , Procesamiento de Imagen Asistido por Computador/métodos , Redes Neurales de la Computación
7.
Appl Opt ; 61(32): 9350-9359, 2022 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-36606881

RESUMEN

Resonance analysis and structural optimization of multi-channel selective fiber couplers currently rely on numerical simulation and manual trial and error, which is very repetitive and time consuming. To realize fast and accurate resonance analysis and calculation, we start with dual-core structures and establish forward classification and regression neural networks to classify and predict different resonance properties, including resonance types, operating wavelength, coupling coefficient, coupling length, 3 dB bandwidth, and conversion efficiency. The pre-trained forward neural networks for dual-core fibers can also realize accurate and fast prediction for multi-core fibers if the mode energy exchange occurs only between one surrounding core and the central core. For the inverse design, a tandem neural network has been constructed by cascading the pre-trained forward neural network and the inverse network to solve the non-uniqueness problem and provide an approach to search for appropriate and desired multi-core structures. The proposed forward and inverse neural networks are efficient and accurate, which provides great convenience for resonance analysis and structural optimization of multi-channel fiber structures and devices.


Asunto(s)
Redes Neurales de la Computación , Simulación por Computador
8.
J Integr Neurosci ; 21(2): 56, 2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35364644

RESUMEN

The long short-term memory network (LSTM) is widely used in time series data processing as a temporal recursive network. The resting-state functional magnetic resonance data shows that not only are there temporal variations in the resting state, but there are also interactions between brain regions. To integrate the temporal and spatial characteristics of brain regions, this paper proposes a model called feature weighted-LSTM (FW-LSTM). The feature weight is defined by spatial characteristics calculating the frequency of connectivity of each brain region and further integrated into the LSTM. Thus, it can comprehensively model both temporal and spatial changes in rs-fMRI brain regions. The FW-LSTM model on the Alzheimer's disease neuroimaging initiative (ADNI) dataset is used to extract the time-varying characteristics of 90 brain regions for Alzheimer's disease (AD) classification. The model performances are 77.80%, 76.41%, and 78.81% in accuracy, sensitivity, and specificity. It outperformed the one-dimensional convolutional neural networks (1D-CNN) model and LSTM model, which only used temporal features of brain regions.


Asunto(s)
Enfermedad de Alzheimer , Imagen por Resonancia Magnética , Enfermedad de Alzheimer/patología , Encéfalo , Humanos , Imagen por Resonancia Magnética/métodos , Redes Neurales de la Computación , Neuroimagen
9.
J Opt Soc Am A Opt Image Sci Vis ; 38(2): 229-236, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33690534

RESUMEN

A tunable dual-ring microstructure fiber that can support stable transmission for different orbital angular momentum (OAM) states and possess ultrahigh dispersion coefficients and low confinement losses is proposed and theoretically investigated. The proposed fiber is composed of two high-refractive-index rings and a double-cladding structure. Owing to the central air core and outer cladding, the dual-ring structure can support stable transmission for the OAM states. The mode fields of different OAM states in the inner ring can spread to the outer ring under certain conditions, which leads to high absolute values of dispersion around the coupling wavelengths. By tuning the refractive indices of the dual rings, the proposed fiber can achieve dispersion control for different OAM modes. Moreover, the specially designed two-layer air holes in the inner cladding can affect the mode-coupling coefficients, which are characterized by the effective mode areas and the overlap integral of the electric fields between the resonant ring modes. Therefore, the dispersion curves and operating wavelengths of the OAM modes can be modulated by regulating the physical parameters (the radius of the two-layer air holes or the infiltrated functional materials) of the inner cladding. We built a theoretical model and analyzed the modulation method and mechanism of the dispersion curves based on the coupled mode theory. The theoretical results indicate that the proposed fiber is flexible and has potential dispersion-compensating applications in fiber OAM systems.

10.
Appl Opt ; 60(34): 10743-10749, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-35200941

RESUMEN

In this study, a high-sensitivity intensity-interrogated fiber sensor integrated with ferrofluids is proposed for the measurement of a weak magnetic field (MF) with resolved temperature cross-sensitivity. The MF sensor is fabricated simply by an offset tapering single-mode fiber concatenated with a multimode fiber (MMF), which is then encapsulated into a capillary tube filled with ferrofluids. In the presence of MMF, stronger mode coupling could be achieved over the S-tapered fiber region. Its spectral response to variations in the applied MF intensity and ambient temperature have been investigated in detail. The proposed sensor shows a high MF sensitivity up to -0.1130dB/Oe for the measurement range of 40 to 120 Oe, which, to our best knowledge, is higher than other previously reported MF sensors. And moreover, the measurement errors caused by temperature cross-sensitivity have been corrected by using a sensing matrix for the temperature range of 25°C to 35°C. Our proposed MF sensor possesses the advantages of high sensitivity, low cost, and applicability for applications in weak MF measurements.

11.
Opt Express ; 28(11): 16996-17009, 2020 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-32549510

RESUMEN

Based on the phased-shifted interference between supermodes, a novel method that can directly convert LP01 mode to orbital angular momentum (OAM) mode in a dual-ring microstructure optical fiber is proposed. In this fiber, the resonance between even and odd HE11 modes in inner ring and higher order mode in outer ring will form two pairs of supermodes, and the intensities and phases of the complete superposition mode fields for the involved supermodes created by the resonance at different wavelengths and propagating lengths are investigated and exhibited in this paper. We demonstrate that OAM mode can be generated from π/2-phase-shifted linear combinations of supermodes, and the phase difference of the even and odd higher order eigenmodes can accumulate to π/2 during the coupling process, which is defined as "phase-shifted" conversion. We build a complete theoretical model and systematically analyze the phase-shifted coupling mechanism, and the design principle and optimization method of this fiber are also illustrated in detail. The proposed microstructure fiber is compact, and the OAM mode conversion method is simple and flexible, which could provide a new approach to generate OAM states.

12.
Cancer Cell Int ; 20: 416, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32874130

RESUMEN

OBJECTIVE: This study aimed to investigate the relationship among miR-145-5p, ANGPT2 and the NOD_LIKE_RECEPTOR pathway, thereby revealing the molecular mechanism of these three factors underlying the proliferation, migration and invasion of gastric cancer (GC) epithelial cells. METHODS: qRT-PCR was carried out to detect the expression of miR-145-5p and ANGPT2 mRNA. Western blot was performed to test the protein levels of ANGPT2 as well as NOD1, NOD2 and NF-κB in the NOD_LIKE_RECEPTOR pathway. The targeting relationship between miR-145-5p and ANGPT2 was verified via a dual-luciferase reporter gene assay. The proliferation, migration and invasion of GC cells were detected through MTT and Transwell assays, respectively. RESULTS: The expression of miR-145-5p was significantly down-regulated in GC cells, while that of ANGPT2 was notably up-regulated. MiR-145-5p directly bound with the 3'-UTR of ANGPT2 mRNA, thereby targeting ANGPT2 after transcription. Overexpression of miR-145-5p inhibited the proliferation, migration and invasion of GC cells by suppressing ANGPT2. Moreover, low expression of ANGPT2 affected the protein levels of NOD1, NOD2 and NF-κB in the NOD_LIKE_RECEPTOR pathway, thus weakening the abilities of cell proliferation, migration and invasion. CONCLUSIONS: MiR-145-5p plays an important role in GC epithelial cells, and it can affect cell proliferation, migration and invasion of GC cells by targeting ANGPT2 and regulating the NOD_LIKE_RECEPTOR pathway. Overall, our study further elucidates the molecular mechanism underlying the malignant progression of GC.

13.
Arch Toxicol ; 93(6): 1573-1584, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30993380

RESUMEN

Early hepatocyte death occurs in most liver injury cases and triggers liver inflammation, which in combination with other risk factors leads to the development of liver disease. However, the pathogenesis of early phase hepatocyte death remains poorly understood. Here, C57BL/6J mice were treated with the hepatotoxic drug flucloxacillin (FLUX) and the toll-like receptor 9 agonist CpG oligodeoxynucleotide (ODN) to reproduce the early phase of drug-induced hepatotoxicity and investigate its pathogenesis. C57BL/6J mice were treated with FLUX (100 mg/kg, gavage) alone or in combination with ODN (40 µg/mouse, intraperitoneally). Plasma alanine aminotransferase (ALT) level was measured as a marker of hepatotoxicity. FLUX or ODN alone was insufficient to induce ALT elevation, whereas combination treatment with FLUX and ODN increased ALT levels 24 h after FLUX treatment and upregulated Fas ligand in natural killer T (NKT) cells and Fas in hepatocytes. FLUX induced mitochondrial permeability transition (MPT), and pretreatment with ODN sensitized mitochondria to FLUX-induced MPT. The increase in ALT levels induced by ODN and FLUX co-treatment was suppressed in Fas ligand (gld/gld)-deficient mice and in mice deficient in a component of MPT pore opening (cyclophilin D-knockout mice). These results suggested that ODN activated the Fas/Fas ligand-mediated pathway in NKT cells and hepatocytes, which may predispose to FLUX-induced mitochondrial dysfunction and lead to early phase hepatocyte apoptosis. Taken together, these findings elucidate a potentially novel mechanism underlying drug-induced early phase hepatocyte death related to the Fas/Fas ligand death receptor pathway and mitochondrial dysfunction.


Asunto(s)
Apoptosis/efectos de los fármacos , Proteína Ligando Fas/efectos de los fármacos , Hígado/efectos de los fármacos , Enfermedades Mitocondriales/patología , Transducción de Señal/efectos de los fármacos , Receptor Toll-Like 9/agonistas , Alanina Transaminasa/sangre , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Proteína Ligando Fas/genética , Femenino , Hepatocitos/efectos de los fármacos , Células Asesinas Naturales/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Enfermedades Mitocondriales/inducido químicamente , Oligodesoxirribonucleótidos
14.
Clin Lab ; 64(1): 11-16, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-29479886

RESUMEN

BACKGROUND: This study is to investigate the application of the bone turnover markers type I procollagen carboxyterminal propeptide (PICP) and ß-isomerized forms of type I collagen breakdown products (ß-CTx) in the diagnosis and treatment of breast cancer with bone metastases. METHODS: A total of 162 breast cancer patients were included in this study. There were 70 cases with bone metastasis (BM group) and 92 cases without bone metastasis (non-bone metastasis, NBM group). The levels of the bone turnover markers PICP and ß-CTx were measured using Electro-Chemiluminescence Immunoassay to compare the difference between BM and NBM group, before and after treatments in the NBM group, and to analyse the relationship with therapeutic effects. RESULTS: The BM group had higher PICP and ß-CTx levels than the NBM group and also higher in the non-luminal type group than the luminal type group, the differences were all statistically significant. However, no statistically significant differences were found among the pN0, pN1, pN2, and pN3 subgroups of the NBM group. Among the 70 cases of BM patient after 3 months of treatment, there were 48 cases that showed clinical benefits, with significantly reduced PICP and ß-CTx levels (p = 0.02, p = 0.00, respectively), but 22 cases showed disease progression with elevated PICP and ß-CTx levels (p = 0.01, p = 0.04, respectively). CONCLUSIONS: The bone turnover markers PICP and ß-CTx have crucial value in the diagnosis and treatment efficacy evaluation for women of breast cancer with bone metastases.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias Óseas/metabolismo , Huesos/metabolismo , Neoplasias de la Mama/metabolismo , Colágeno Tipo I/análisis , Fragmentos de Péptidos/análisis , Péptidos/análisis , Procolágeno/análisis , Adulto , Anciano , Neoplasias Óseas/secundario , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Femenino , Humanos , Persona de Mediana Edad , Sensibilidad y Especificidad
15.
Arch Toxicol ; 92(3): 1177-1188, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29150704

RESUMEN

Immune-mediated idiosyncratic drug toxicity (IDT) is a rare adverse drug reaction, potentially resulting in death. Although genome-wide association studies suggest that the occurrence of immune-mediated IDT is strongly associated with specific human leukocyte antigen (HLA) allotypes, these associations have not yet been prospectively demonstrated. In this study, we focused on HLA-B*57:01 and abacavir (ABC)-induced immune-mediated IDT, and constructed transgenic mice carrying chimeric HLA-B*57:01 (B*57:01-Tg) to determine if this in vivo model may be useful for evaluating immune-mediated IDT. Local lymph node assay (LLNA) results demonstrated that percentages of BrdU+, IL-2+, and IFN-γ+ in CD8+ T cells of ABC (50 mg/kg/day)-applied B*57:01-Tg mice were significantly higher than those in littermates (LMs), resulting in the infiltration of inflammatory cells into the ear. These immune responses were not observed in B*57:03-Tg mice (negative control). Furthermore, oral administration of 1% (v/v) ABC significantly increased the percentage of CD44highCD62Llow CD8+ memory T cells in lymph nodes and spleen derived from B*57:01-Tg mice, but not in those from B*57:03-Tg mice and LMs. These results suggest that B*57:01-Tg mice potentially enable the reproduction and evaluation of HLA-B*57:01 and ABC-induced immune-mediated IDT.


Asunto(s)
Didesoxinucleósidos/efectos adversos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/inmunología , Antígenos HLA-B/inmunología , Pruebas de Toxicidad/métodos , Administración Oral , Animales , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Didesoxinucleósidos/administración & dosificación , Didesoxinucleósidos/toxicidad , Antígenos HLA-B/genética , Humanos , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/inmunología , Ratones Endogámicos C57BL , Ratones Transgénicos
16.
Yao Xue Xue Bao ; 52(3): 416-24, 2017 Mar.
Artículo en Zh | MEDLINE | ID: mdl-29979850

RESUMEN

This study was conducted to design and synthetize highly efficient, specific, non-resistant small MEK inhibitors. Based on active small molecules which have been reported, we studied the action mode with MEK protein using Autodock 4.2, generated innovative and feasible design method, designed novel small MEK protein inhibitors with a reference to molecular modeling and docking. The anti-tumor activities of four kinds of cells including MCF-7, PANC-1, SY5Y, A549 were tested with MTT method in vitro. The structure of 10 new small molecules has been determined with 1H NMR and 13C NMR. The compounds 4, 6, 7, 8, 10 had high antitumor activities, the compounds 1, 3, 5 also showed good activity, and the compounds 2, 9 showed cell selectivity in killing tumor.


Asunto(s)
Antineoplásicos/química , Diseño de Fármacos , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/química , Línea Celular Tumoral , Proliferación Celular , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Modelos Moleculares , Estructura Molecular , Relación Estructura-Actividad
17.
Opt Express ; 23(9): 11123-34, 2015 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-25969208

RESUMEN

In this paper, a magnetically controllable wavelength-division-multiplexing (WDM) fiber coupler has been proposed and experimentally demonstrated. A theoretical model has been established to analyze the influences of the weak as well as strong couplings to the wavelength tunability of this coupler. Experimental results show that the operation wavelength tunability of the proposed WDM coupler could be fulfilled for an applied magnetic field intensity range of 0 Oe to 500 Oe, and particularly it possesses high operation performances within the magnetic field intensity ranging from 25 Oe to 125 Oe when additional transmission loss and isolation are both considered. Within this range, the two selected channels show the wavelength tunability of 0.05 nm/Oe and 0.0744 nm/Oe, respectively, and the isolation between the two branches is higher than 24.089 dB. Owing to its high isolation, good splitting ratio stability, and high wavelength tunability, the proposed controllable WDM coupler is anticipated to find potential applications in such fields as fiber laser, fiber sensing and fiber-optic communications. Moreover, the fiber coupler integrated with the magnetic fluid would be valuable for the design of magnetically controllable mode-division-multiplexing devices.

18.
Opt Express ; 23(12): 15372-9, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-26193517

RESUMEN

A highly sensitive optical fiber twist sensor has been proposed by employing a Sagnac interferometer based on polarization-maintaining elliptical core fibers (PM-ECFs). The twist effects have been theoretically analyzed and experimentally demonstrated. Based on the photoelastic effect, the resonance wavelength linearly shifts with the increment of twist and the wavelength shift is also dependent on the torsion direction. The maximum torsion sensitivities reach 18.60nm/(rad/m) for clockwise (CW) torsion direction and 15.83nm/(rad/m) for anticlockwise (ACW) torsion direction, respectively. To eliminate the temperature cross-sensitivity effect, a sensor matrix for simultaneous measurement of twist and temperature has also been obtained. Moreover, theoretical and experimental investigations indicate that by optimizing the refractive index difference between the core and cladding, core ellipticity and cladding diameter, the twist sensitivity could be further improved.

19.
Opt Lett ; 40(16): 3905-8, 2015 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-26274690

RESUMEN

A compact fiber-optic magnetic-field sensor based on tapered all-solid waveguide-array fiber (WAF) and magnetic fluid (MF) has been proposed and experimentally demonstrated. The tapered all-solid WAF is fabricated by using a fusion splicer, and the sensor is formed by immersing the tapered all-solid WAF into the MF. The transmission spectra have been measured and analyzed under different magnetic-field intensities. Experimental results show that the acquired magnetic-field sensitivity is 44.57 pm/Oe for a linear magnetic-field intensity range from 50 to 200 Oe. All-solid WAF has very similar thermal expansion coefficient for high- and low-refractive-index glasses, so mode profile is not affected by thermal drifts. Also, magnetically induced refractive-index changes into the ferrofluid are of the order of ∼5×10(-2), while the corresponding thermally induced refractive-index changes into the ferrofluid are expected to be lower. The temperature response has also been detected, and the temperature-induced wavelength shift perturbation is less than 0.3 nm from temperature of 26.9°C-44°C. The proposed magnetic-field sensor has such advantages as low temperature sensitivity, simple structure, and ease of fabrication. It also indicates that the magnetic-field sensor based on tapered all-solid WAF and MF is helpful to reduce temperature cross-sensitivity for the measurement of magnetic field.

20.
Br J Nutr ; 114(7): 1064-71, 2015 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-26395322

RESUMEN

Postmenopausal women are at increased risk of CVD: the increased serum ferritin level may be involved in the pathogenesis. The aim of the present study is to investigate the relationship of ferritin and carotid atherosclerosis in postmenopausal women. A total of 1178 postmenopausal women (mean age, 60·8 years) were enrolled from the Changfeng Study. A standard interview, anthropometric measurements and laboratory analyses were performed for each participant. Bilateral CIMT (carotid intima-media thickness) were measured using ultrasonography, and the presence of carotid plaques was assessed. Serum ferritin was measured using electrochemiluminescence immunoassay. The results showed that serum ferritin was 181·9 (sd 65·8) ng/ml in the postmenopausal women. Multivariate, linear, stepwise regression analysis demonstrated that age (standardised ß = 0·233, P< 0·001), alanine transaminase (standardised ß = 0·194, P< 0·001), log homeostasis model assessment index for insulin resistance (standardised ß = 0·181, P< 0·001), TAG (standardised ß = 0·083, P= 0·003), Hb (standardised ß = 0·080, P= 0·004) and PPG (2-h glucose levels following a 75-g oral glucose challenge) (standardised ß = 0·079, P= 0·004) were independently associated with serum ferritin. Compared with the ferritin level of subjects in the first quartile, that in the fourth quartile had greater CIMT, and higher prevalence of carotid plaque. After adjusting for conventional CVD risk factors, Hb, leucocytes, log urine albumin:creatinine ratio and liver function, the ferritin level of postmenopausal women in the fourth quartile had a 1·587-fold increased risk of carotid plaques relative to those in the lowest quartile. In conclusion, these results suggest that serum ferritin is independently and positively associated with carotid atherosclerosis in postmenopausal women and that ferritin may be implicated in atherosclerosis.


Asunto(s)
Pueblo Asiatico , Enfermedades de las Arterias Carótidas/sangre , Ferritinas/sangre , Placa Aterosclerótica/sangre , Posmenopausia/sangre , Alanina Transaminasa/sangre , Enfermedades de las Arterias Carótidas/etnología , Grosor Intima-Media Carotídeo , China/epidemiología , Estudios Transversales , Femenino , Humanos , Resistencia a la Insulina , Persona de Mediana Edad , Análisis Multivariante , Placa Aterosclerótica/etnología , Prevalencia , Factores de Riesgo
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