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A novel magnetic field measurement method based on the magneto-volume effect is proposed. The magnetic field sensing structure fabricated by the proposed measurement method is made by the magnetic fluid (MF) partially filled into the hollow core fiber (HCF). The presence of air provides conditions for the change of MF volume with the magnetic field in the proposed sensing structure. Therefore, the magneto-volume effect is introduced into the magnetic field sensing mechanism. From 109.6 to 125.8 Gs, the peak wavelength shift is −65480 pm and the sensitivity is −4219.15 pm/Gs, which is 28.16 times higher than that of the fabricated contrast sensing structure. The sensitivity of the magnetic field sensing structure is greatly improved by introducing the magneto-volume effect compared with the contrast sensing structure. The response time and recovery time of the sensing structure are equally 0.2 s. Therefore, the sensing structure has high sensitivity, good linearity, and short response time, which has potential application prospects in magnetic field sensing. [ABSTRACT FROM AUTHOR]

A magnetic field measurement method based on the magneto-volume effect of magnetic fluid (MF) and Fabry–Perot (FP) interferometer (FPI) is proposed, which has higher magnetic field sensitivity and shorter response time than the traditional optical fiber methods. The MF is partially injected into the fabricated FP cavity composed of two sections of SMFs and a capillary glass tube (CGT), where the FPI is made up of optical fiber end face and MF end face. When the external magnetic field is applied to the sensor, the volume change of MF will cause the change of air cavity length. Therefore, the reflection spectrum changes with external magnetic field due to the magneto-volume effect of MF. Experimental results show that the magnetic field sensor shows a sensitivity of 268.81 pm/Gs from 15.5 to 139.7 Gs even with a small amount of MF. The response time is 0.2 s at a step magnetic field of 7.7, 31.0, 46.5, and 139.7 Gs. In this work, the magnetic field sensor boasts high sensitivity, good repeatability, short response time, and low cost, which shows a great potential in applications. [ABSTRACT FROM AUTHOR]

A highly sensitive reflective Fabry–Perot (FP) magnetic field sensor using magnetic fluid (MF) based on the Vernier effect is presented and experimentally verified. Capillary action acts as an injection of MF into an FP cavity, which is composed of a single-mode fiber (SMF), capillary glass tube, and a short section of SMF coated with gold film. Vernier effect is formed by the MF cavity and air cavity in the FP magnetic field sensor, where the surface of MF is concave. The refractive index (RI) of MF depends on the magnetic field, and therefore, the wavelength of the reflection spectrum of the fabricated sensor can be sensitive to the magnetic field. The magnetic field sensor’s sensitivity is up to 1.02602 nm/Gs from 118.768 to 166.261 Gs, and the resolution is 0.0078 Gs. The sensor shows good linearity within the range of 71.317–231.751 Gs, and the linearity is larger than 0.999. In this article, a new type FP cavity fabricated by splicing SMF inside the capillary glass tube is proposed, and MF can be injected into the FP cavity, which can also be applied to other liquids to generate Vernier effect. The concave surface of MF is creatively applied to the sensors, and the experimental verification is carried out in a capillary glass tube, which provides a basis on the capillary action of other fluids in fiber sensing. [ABSTRACT FROM AUTHOR]

• The magnetic field sensor composed of an ultra-short FPI filled with oil-based magnetic fluid cascaded with a bending coated single-mode-fiber MZI is proposed. • The FPI with ultra-short cavity (about 20 μm) composed of two sections of single mode fiber and a hollow core fiber drilled through by femtosecond laser. • The sensitivities of magnetic field and temperature are up to 240 pm/Gs and −2310 pm/℃ respectively. A fiber magnetic field sensor with temperature compensation is put forward and experimentally verified by utilizing Fabry-Perot interferometer (FPI) and multimode interferometer (MI). The FPI with ultra-short cavity (about 20 μm), which is proposed to improve the spectrum contrast after being filled with oil-based magnetic fluids (MF) and achieve the sensing of magnetic field, is drilled through by femtosecond laser. The FPI is composed of two sections of single mode fiber and a hollow core fiber, which is named as single mode fiber-hollow core fiber-single mode fiber (SHS). The MI composed of the coated-fiber-loop, which is only sensitive to temperature, is proposed to compensate the temperature on the sensing of magnetic field. The fiber loop is fabricated by only bending a section of coated single mode fiber (SMF). According to the experiment results, the spectrum visibility of magnetic field sensing part can be improved by 3.1 times by shortening the Fabry-Perot (FP) cavity length. The interference wavelength increases nonlinearly from 0 to 69.1 Gs while linearly from 69.1 to 137.7 Gs. In addition, its temperature sensitivity is −0.20 nm/℃ from 23.0 to 42.9 ℃. Moreover, the sensitivity of MI is −2.31 nm/℃ from 23.0 to 42.9 ℃. It could be used to compensate the temperature influence effectively. The structure boasts characteristics of simple manufacture, low cost and highly-sensitive, which can be applied in the fields of magnetic field sensing. [ABSTRACT FROM AUTHOR]

• Magneto-shape effect of magnetic fluid was proposed and used to measure magnetic field. • The sensor consists of a capillary glass tube, two single-mode fibers and magnetic fluid. • Experimental results show that the sensor can easily react to field strength and orientation. • Measurement sensitivity reaches up to 296.1 pm/Gs from 22.6 Gs to 121.8 Gs in the axial field. In this work, an optic-fiber sensor utilizing magneto-shape effect of magnetic fluid (MF) has been put forward to measure magnetic field direction. MF magneto-shape effect has been presented, simulated and verified through experiments as a magneto-optical effect. The sensor consists of a capillary glass tube, two single-mode fibers (SMFs) and MF. The interface between MF and air is concave because the glass tube is attractive to MF. As magnetic field rises, the concavity degree becomes more obvious, in other words, edge length of MF cavity is extended and central length of cavity is shortened. The interference wavelength of sensor will change with magnetic field, so as to achieve the purpose of monitoring magnetic field. The phenomenon is defined as the magneto-shape effect of MF. Due to the magnetic field direction dependence of pressure difference between the MF and air, the magneto-shape effect of MF has different perception of axial magnetic field and radial magnetic field, realizing vector magnetic field measurement. Results of experiment are shown as follows: the sensor can easily react to field strength and orientation. The wavelength shows the shape of number "8″ with magnetic field direction changing. The field sensitivity reaches up to 296.1 pm/Gs from 22.6 Gs to 121.8 Gs in the axial field. Moreover, direction sensitivity reaches 311.6 pm/° at 104.4 Gs. The wavelength shift in the axial direction is 25.5 times higher than that of the radial direction. The presented sensing structure could monitor vector magnetic field without constructing a non-circular symmetrical structure. The proposed sensing structure is provided with characteristics of simple to make, highly-sensitive and little fabrication consumption. It possesses potential applications in electronic power industry and aerospace. [ABSTRACT FROM AUTHOR]

In this study, a fiber-optic sensor based on Fabry-Perot interferometer (FPI) and Mach-Zehnder interferometer (MZI) cascaded structure is proposed and demonstrated for seawater salinity and temperature simultaneous measurements. A section of hollow-core fiber (HCF) with a U-shaped defect is spliced between single-mode fibers to form FPI. The U-shaped defect inscribed by the femtosecond laser facilitates liquid flow-through and enables the salinity measurement. The MZI composes of laser-induced optical waveguides written in the cladding of the coating-retained single-mode fiber. There is an interaction between the evanescent field of the in-fiber waveguides and the coating due to the written waveguide is close to the cladding-coating interface. Part of the incident light is reflected by HCF to form the FPI spectrum, while the transmitted light in the core is coupled to the written waveguides and guided along the cladding region, which finally returned to the core to obtain the MZI spectrum. Theoretical analysis and experimental verification are carried out, and the results show that the proposed sensor offers a salinity sensitivity of 0.244 nm/‰ and a temperature sensitivity of − 2.767 nm/℃. Such a cascaded interferometer has advantages of high sensitivity and compact size, which is expected to be widely used in seawater parameter measurements due to the flexible structure and precise control. • An F-P and M-Z interferometer cascaded fiber-optic sensor is proposed for salinity and temperature measurements. • F-P interferometer is formed by splicing a section of hollow-core fiber with a femtosecond laser-inscribed U-shaped defect. • M-Z interferometer composes of laser-induced optical waveguides written in the cladding of the fiber. • The sensor realizes simultaneous salinity and temperature measurements with sensitivities of 0.244 nm/‰ and − 2.767 nm/℃. [ABSTRACT FROM AUTHOR]

In this study, a fiber-optic sensor based on Fabry-Perot interferometer (FPI) and Mach-Zehnder interferometer (MZI) cascaded structure is proposed and demonstrated for seawater salinity and temperature simultaneous measurements. A section of hollow-core fiber (HCF) with a U-shaped defect is spliced between single-mode fibers to form FPI. The U-shaped defect inscribed by the femtosecond laser facilitates liquid flow-through and enables the salinity measurement. The MZI composes of laser-induced optical waveguides written in the cladding of the coating-retained single-mode fiber. There is an interaction between the evanescent field of the in-fiber waveguides and the coating due to the written waveguide is close to the cladding-coating interface. Part of the incident light is reflected by HCF to form the FPI spectrum, while the transmitted light in the core is coupled to the written waveguides and guided along the cladding region, which finally returned to the core to obtain the MZI spectrum. Theoretical analysis and experimental verification are carried out, and the results show that the proposed sensor offers a salinity sensitivity of 0.244 nm/‰ and a temperature sensitivity of − 2.767 nm/℃. Such a cascaded interferometer has advantages of high sensitivity and compact size, which is expected to be widely used in seawater parameter measurements due to the flexible structure and precise control. • An F-P and M-Z interferometer cascaded fiber-optic sensor is proposed for salinity and temperature measurements. • F-P interferometer is formed by splicing a section of hollow-core fiber with a femtosecond laser-inscribed U-shaped defect. • M-Z interferometer composes of laser-induced optical waveguides written in the cladding of the fiber. • The sensor realizes simultaneous salinity and temperature measurements with sensitivities of 0.244 nm/‰ and − 2.767 nm/℃. [ABSTRACT FROM AUTHOR]

In this article, a reflective-type optical fiber probe, which can measure salinity and temperature simultaneously, is proposed. The proposed probe integrates Mach–Zehnder interferometer and Fabry–Perot interferometer in the same channel skillfully and effectively, which makes it possible to integrate more information into the sensor. The reflected spectrum is improved greatly by adopting special sputtering technology. The spectrums of Mach–Zehnder and Fabry–Perot are separated by applying the frequency division multiplex technique. The simulation and experimental results prove that the proposed probe has a highly sensitive response to temperature and salinity. The experiment result verifies that the salinity sensitivity is up to 2.7 nm/‰ and the temperature sensitivity is better than 0.4 nm/°C. The reflective probe makes the sensor easy to use and paves the way for practical application. [ABSTRACT FROM AUTHOR]

For the purpose of monitoring seawater temperature, a novel Mach–Zehnder (MZ) temperature-sensing structure with a wedge-shaped open cavity is presented and experimentally studied in this article. The open-cavity structure realizes the direct contact between the sensing optical path and the external environment, and ensures the high sensitivity of the structure. At the same time, it achieves not only low loss by direct fusion splicing instead of dislocation fusion splicing, but also low cost by hydrofluoric (HF) etching instead of femtosecond processing. In addition, the temperature sensitivity of the sensor structure proposed in this article can reach 1.5 nm/°C without temperature-sensitive material filled, and 6 nm/°C with silicone oil filled. Moreover, the resolution of the sensing structure is 0.24 °C based on the criterion of $3\sigma $. [ABSTRACT FROM AUTHOR]

Three series of novel AHL analogs were synthesized and evaluated for their in vitro cytotoxic activity against four human cancer cell lines. The SARs investigation indicated that AHLs with a terminal phenyl group, especially those with the chalcone scaffold had remarkably enhanced cytotoxicity than those with the hydrophobic side chains. Besides, some of these compounds were much more potent than 5-Fu and natural OdDHL. Through the detailed SARs discussions, we found that compounds 10a-k and 14 with the 4-amino chalcone scaffold showed excellent inhibition against all the tested cancer cell lines and were much more potent than 5-Fu and AHLs. Such scaffold may act as a template for further lead optimization. Compound 10i with a 3, 4, 5-trimethoxy group was the most potent one against all the tested cancer cell lines. Flow cytometry analysis indicated that analog 11e induced the cellular apoptosis and cell cycle arrest of MCF-7 cells at G2/M phase in a concentration-and time-dependent manner. [ABSTRACT FROM AUTHOR]

Many published studies reflect the growing application of complementary and alternative medicine, particularly Chinese herbal medicine (CHM) use in combination with conventional cancer therapy for advanced non-small cell lung cancer (NSCLC), but its efficacy remains largely unexplored. The purpose of this study is to evaluate the efficacy of CHM combined with conventional chemotherapy (CT) in the treatment of advanced NSCLC. Publications in 11 electronic databases were extensively searched, and 24 trials were included for analysis. A sum of 2,109 patients was enrolled in these studies, at which 1,064 patients participated in CT combined CHM and 1,039 in CT (six patients dropped out and were not reported the group enrolled). Compared to using CT alone, CHM combined with CT significantly increase one-year survival rate (RR = 1.36, 95% CI = 1.15–1.60, p = 0.0003). Besides, the combined therapy significantly increased immediate tumor response (RR = 1.36, 95% CI = 1.19–1.56, p<1.0E−5) and improved Karnofsky performance score (KPS) (RR = 2.90, 95% CI = 1.62–5.18, p = 0.0003). Combined therapy remarkably reduced the nausea and vomiting at toxicity grade of III–IV (RR = 0.24, 95% CI = 0.12–0.50, p = 0.0001) and prevented the decline of hemoglobin and platelet in patients under CT at toxicity grade of I–IV (RR = 0.64, 95% CI = 0.51–0.80, p<0.0001). Moreover, the herbs that are frequently used in NSCLC patients were identified. This systematic review suggests that CHM as an adjuvant therapy can reduce CT toxicity, prolong survival rate, enhance immediate tumor response, and improve KPS in advanced NSCLC patients. However, due to the lack of large-scale randomized clinical trials in the included studies, further larger scale trials are needed. [ABSTRACT FROM AUTHOR]

• The proposed method realizes the large dynamic range and the high accuracy demodulation with less extra computation, which integrates the advantages of DGT and phase methods. • By applying phase difference compensation technology, the OPD demodulation resolution achieves 45.37 pm, and the demodulation accuracy improves about 10,000 times. • The proposed method can also combine with other methods for improving the demodulation accuracy. A novel method, which is based on the phase difference between the filtered spectrum and simulated spectrum, is proposed to compensate for the optical path difference (OPD) demodulation error of the interferometer sensors. With applying the phase difference technology, large dynamic range OPD demodulation with high accuracy is realized. Its principle is deduced by theoretical analysis. The numerical simulation is conducted in the presence of noise, amplitude variation, and constant offset, verifies that the proposed method is robust. The strain experiment result shows that the demodulation resolution is 45.37 pm at the cavity length of around 328 μm. The demodulation accuracy improves about 10,000 times compares with the DGT method, and the demodulation resolution is achieved to the same order as the most advanced method with less computation. And the phase difference technology can be applied to other demodulation methods for high demodulation accuracy. [ABSTRACT FROM AUTHOR]