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1.
Mol Genet Genomics ; 299(1): 27, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38466442

RESUMO

Genome walking, a molecular technique for obtaining unknown flanking genomic sequences from a known genomic sequence, has been broadly applied to determine transgenic sites, mine new genetic resources, and fill in chromosomal gaps. This technique has advanced genomics, genetics, and related disciplines. Here, an efficient and reliable genome walking technique, called primer extension refractory PCR (PER-PCR), is presented. PER-PCR uses a set of primary, secondary, and tertiary walking primers. The middle 15 nt of the primary walking primer overlaps with the 3' parts of the secondary and tertiary primers. The 5' parts of the three primers are heterologous to each other. The short overlap allows the walking primer to anneal to its predecessor only in a relaxed-stringency PCR cycle, resulting in a series of single-stranded DNAs; however, the heterologous 5' part prevents the creation of a perfect binding site for the walking primer. In the next stringent cycle, the target single strand can be extended into a double-stranded DNA molecule by the sequence-specific primer and thus can be exponentially amplified by the remaining stringent cycles. The nontarget single strand fails to be enriched due to the lack of a perfect binding site for any primer. PER-PCR was validated by extension into unknown flanking regions of the hyg gene in rice and the gadR gene in Levilactobacillus brevis CD0817. In summary, in this study, a new practical PER-PCR method was constructed as a potential alternative to existing genome walking methods.


Assuntos
DNA , Genômica , Reação em Cadeia da Polimerase/métodos , Genômica/métodos , DNA de Cadeia Simples
2.
Opt Express ; 32(6): 9456-9467, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571180

RESUMO

Traditional optical information recognition (OIR), particle capture and manipulation require many optical devices or mechanical moving system components to achieve a specific function, which is difficult to achieve integration. This paper proposes a new method to realize these functions by using multi-focus metalens combining spectrum and polarization selection. The design incorporates three spectral bands, namely 500 nm, 580 nm, and 660 nm, within the visible light range. Additionally, it utilizes either left-handed or right-handed circularly polarized (LCP/RCP) light, resulting in six distinct focus focusing effects on a single focal plane. By analyzing the normalized light intensity (NLI) at the corresponding focus position, the OIR of any wavelength and polarization detection in the design can be realized, and the particle capture at different focusing positions can be realized. Our work can provide a new idea for the high integration of on-chip light recognition and operation and inspire the design of a highly integrated optical system with a smaller size and more substantial function.

3.
BMC Womens Health ; 24(1): 426, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39061005

RESUMO

BACKGROUND: This study aims to analyze the efficacy of metformin on carotid intima media thickness (CIMT) and flow-mediated dilation (FMD) for patients with polycystic ovary syndrome (PCOS). METHODS: A literature search of PubMed, Embase, and the Cochrane Library from inception to December 2023 was conducted. Then, after studies selection and data extraction, the mean difference (MD) with a 95% confidence interval (CI) was used to evaluate metformin efficacy in CIMT and FMD for PCOS patients. Heterogeneity was investigated through subgroup and sensitivity analysis. The protocol of our study has been registered in PROSPERO (CRD42024497239). RESULTS: A total of 12 studies with 248 patients were included. CIMT was lower in the endpoint group (after metformin) compared with the baseline group (before metformin) (MD = -0.11, 95% CI = -0.21 to -0.01, p = 0.04). FMD was higher in the endpoint group compared with the baseline group (MD = 3.25, 95% CI = 1.85 to 4.66, p < 0.01). No statistically significant difference was observed in nitroglycerin-mediated dilation (NMD) between the two groups (MD = 0.65, p = 0.51). Subgroup analysis showed that a relatively lower MD of CIMT in PCOS patients from Europe in the endpoint group compared with the baseline group (MD = -0.09, 95% CI = -0.14 to -0.04, p < 0.001). However, the MD in CIMT was not significantly different between the endpoint group and baseline group in PCOS patients from Asia (p = 0.270). CONCLUSION: Metformin may have a beneficial effect on CIMT and FMD, but not on NMD, suggesting that metformin may help reduce cardiovascular events in PCOS patients. Notably, the clinical efficacy of metformin can be influenced by regional differences and study types.


Assuntos
Espessura Intima-Media Carotídea , Metformina , Síndrome do Ovário Policístico , Humanos , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/complicações , Metformina/uso terapêutico , Feminino , Vasodilatação/efeitos dos fármacos , Hipoglicemiantes/uso terapêutico
4.
Artigo em Inglês | MEDLINE | ID: mdl-39212508

RESUMO

Context: The neutrophil to lymphocyte ratio (NLR) or platelet to lymphocyte ratio (PLR) is an inflammation marker of acute ischemic stroke, but the predictive value of NLR and PLR before and after thrombolysis for short-term prognosis in acute ischemic stroke patients after thrombolysis remains largely obscure. This study attempts to clarify the predictive value of NLR and PLR before and after thrombolysis for short-term prognosis in acute ischemic stroke patients after thrombolysis. Design: A retrospective study was carried out in the Affiliated Hospital of Hangzhou Normal University involving 120 patients visiting the neurology department of our hospital from May 2019 to October 2022 and meeting the selection criteria. The participants were assigned to the good prognosis group and the poor prognosis group based on the modified Rankin scale score. Laboratory data collected include NLR and PLR at admission as well as NLR and PLR collected from venous blood within 24 h after thrombolysis. Results: Age, hyperlipidemia, atrial fibrillation, rheumatic heart disease, and National Institutes of Health Stroke Scale (NIHSS) scores after thrombolysis depicted statistical significance between both groups (P < .05). Hyperlipidemia, atrial fibrillation, and NIHSS scores before thrombolysis were independent risk elements for adverse prognosis (P < .05). NLR and PLR before and after thrombolysis in the poor prognosis group depicted an elevation relative to that in the good prognosis group (P < .05). The area under the curve of NLR or PLR predicting adverse prognosis after thrombolysis depicted an elevation relative to that before thrombolysis (P < .05). Conclusion: The predictive value of NLR and PLR post-thrombolysis for short-term prognosis in acute ischemic stroke patients depicts an elevation relative to pre-thrombolysis; our study provides effective predictive indicators for short-term prognosis in acute ischemic stroke patients.

5.
BMC Surg ; 24(1): 239, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39174997

RESUMO

BACKGROUND: Endoscopic nasobiliary drainage (ENBD) is used as a drainage technique in patients with choledocholithiasis after stone removal. However, ENBD can cause discomfort, displacement, and other complications. This study aims to evaluate the safety of not using ENBD following elective clearance of choledocholithiasis. METHODS: Relevant studies were identified by searching PubMed, Web of Science, EMBASE, EBSCO, and Cochrane Library from their inception until August 2023. The main outcomes assessed were postoperative complications and postoperative outcomes. Subgroup analyses were conducted based on study design types and treatment procedures. RESULTS: Six studies, including three randomized controlled trials (RCTs) and three cohort studies, were analyzed. Among these, four studies utilized endoscopic techniques, and two employed surgical methods for choledocholithiasis clearance. The statistical analysis showed no significant difference in postoperative complications between the no-ENBD and ENBD groups, including pancreatitis (RR: 1.55, p = 0.36), cholangitis (RR: 1.81, p = 0.09), and overall complications (RR: 1.25, p = 0.38). Regarding postoperative outcomes, the subgroup analysis indicated that the bilirubin normalization time was longer in the no-ENBD group compared to the ENBD group in RCTs (WMD: 0.24, p = 0.07) and endoscopy studies (WMD: 0.23, p = 0.005), although the former did not reach statistical difference. There was also no significant difference in the length of postoperative hospital stay between the groups (WMD: -0.30, p = 0.60). CONCLUSION: It appears safe to no- ENBD after elective clearance of choledocholithiasis.


Assuntos
Coledocolitíase , Drenagem , Procedimentos Cirúrgicos Eletivos , Complicações Pós-Operatórias , Humanos , Coledocolitíase/cirurgia , Drenagem/métodos , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Procedimentos Cirúrgicos Eletivos/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Opt Express ; 31(5): 8668-8681, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36859977

RESUMO

Metalens with extended depth of focus (EDOF) can extend the mapping area of the image, which leads to novel applications in imaging and microscopy. Since there are still some disadvantages for existing EDOF metalenses based on forward design, such as asymmetric point spread function (PSF) and non-uniformly distributed focal spot, which impair the quality of images, we propose a double-process genetic algorithm (DPGA) optimization to inversely design the EDOF metalens for addressing these drawbacks. By separately adopting different mutation operators in successive two genetic algorithm (GA) processes, DPGA exhibits significant advantages in searching for the ideal solution in the whole parameter space. Here, the 1D and 2D EDOF metalenses operating at 980 nm are separately designed via this method, and both of them exhibit significant depth of focus (DOF) improvement to that of conventional focusing. Furthermore, a uniformly distributed focal spot can be maintained well, which can guarantee stable imaging quality along the longitudinal direction. The proposed EDOF metalenses have considerable potential applications in biological microscopy and imaging, and the scheme of DPGA can be promoted to the inverse design of other nanophotonics devices.

7.
Nutr Cancer ; 75(2): 627-639, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36372063

RESUMO

This study aimed to investigate the effects of polyunsaturated fatty acids (PUFAs) on patients with colorectal cancer (CRC). Electronic databases such as PubMed and Web of Science were searched. Studies on the application of PUFAs in patients with CRC, published up to January 2022, were conducted. Twelve studies involving 702 CRC patients were included. For patients undergoing surgery, subgroup analyses indicated that preoperative supplementation with PUFAs improved total postoperative infectious complications (RR: 0.37, p = 0.02). Furthermore, the supplementation of PUFAs in preoperative (WMD: -2.27, p < 0.001) and postoperative (WMD: -2.66, p = 0.01) groups was effective in shortening the postoperative hospital stay for patients with CRC. Tumor necrosis factor-α (TNF-α) (SMD: -0.56, p = 0.007) and interleukin-6 (IL-6) (SMD: -0.54, p = 0.004) levels were lower in all CRC patients receiving PUFAs intervention than in the control group. Moreover, supplementation with PUFAs in chemotherapy patients significantly increased albumin (WMD: 0.48, p = 0.03) and decreased C-reactive protein (CRP) (WMD: -6.12, p = 0.02) compared to the control group. This study demonstrated that PUFAs intervention could diminish the total postoperative infection complications of CRC patients, shorten the postoperative hospital stay, and reduce inflammation.


Assuntos
Neoplasias Colorretais , Ácidos Graxos Ômega-3 , Humanos , Ácidos Graxos Ômega-3/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Ácidos Graxos Insaturados , Inflamação/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/cirurgia , Suplementos Nutricionais
8.
BMC Infect Dis ; 23(1): 852, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053032

RESUMO

BACKGROUND: Motor neuron disease (MND) is a fatal neurodegenerative disorder that leads to progressive loss of motor neurons. Chlamydia psittaci (C. psittaci) is a rare etiology of community-acquired pneumonia characterized primarily by respiratory distress. We reported a case of C. psittaci pneumonia complicated with motor neuron disease (MND). CASE PRESENTATION: A 74-year-old male was referred to the Shaoxing Second Hospital at January, 2022 complaining of fever and fatigue for 2 days. The patient was diagnosed of MND with flail arm syndrome 1 year ago. The metagenomic next-generation sequencing (mNGS) of sputum obtained through bedside fiberoptic bronchoscopy showed C. psittaci infection. Then doxycycline was administrated and bedside fiberoptic bronchoscopy was performed to assist with sputum excretion. Computed Tomography (CT) and fiberoptic bronchoscopy revealed a significant decrease in sputum production. On day 24 after admission, the patient was discharged with slight dyspnea, limited exercise tolerance. One month later after discharge, the patient reported normal respiratory function, and chest CT showed significant absorption of sputum. CONCLUSIONS: The mNGS combined with bedside fiberoptic bronchoscopy could timely detect C. psittaci infection. Bedside fiberoptic bronchoscopy along with antibiotic therapy may be effective for C. psittaci treatment.


Assuntos
Chlamydophila psittaci , Doença dos Neurônios Motores , Pneumonia , Psitacose , Masculino , Humanos , Idoso , Psitacose/complicações , Psitacose/diagnóstico , Psitacose/tratamento farmacológico , Brônquios , Doença dos Neurônios Motores/complicações , Doença dos Neurônios Motores/diagnóstico , Dispneia
9.
World J Surg Oncol ; 21(1): 340, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37880688

RESUMO

BACKGROUND: Adding anti-epidermal growth factor receptor (anti-EGFR) target agents to conversion therapy may improve the resection rates and survival of patients with potentially resectable metastatic colorectal cancer (mCRC). This study aims to analyze the efficacy and safety of additional anti-EGFR target agents. METHODS: A systematic search was conducted on PubMed, Web of Science, Embase, and Cochrane Library. And all relevant studies published in English before January 2023 were collected to explore the impact of additional anti-EGFR targeted agent on the efficacy and safety of patients with potentially resectable mCRC (PROSPERO: CRD42022340523, https://www.crd.york.ac.uk/PROSPERO/ ). RESULTS: This study included a total of 8 articles, including 2618 patients. The overall response rate (ORR) and R0 resection rates of the experimental group were higher than those of the control group, while there was no significant difference in progression-free survival (PFS) and overall survival (OS) between the two groups. In RAS/KRAS wild-type patients, the ORR (RR: 1.20, 95% Cl: 1.02-1.41, p = 0.03), R0 resection rate (RR: 1.60, 95% Cl: 1.17-2.20, p = 0.003), PFS (HR: 0.80, 95% Cl: 0.68-0.93, p = 0.003), and OS (HR: 0.87, 95% Cl: 0.76-0.99, p = 0.031) of the experimental group were higher than those of the control group. While in KRAS mutant patients, there was no statistical difference between the two groups in ORR, R0 resection rate, PFS, and OS. CONCLUSION: The addition of anti-EGFR targeted agents can improve the prognosis of RAS/KRAS wild-type patients with potentially resectable mCRC, while KRAS mutant patients may not benefit. In addition, the overall safety factor was controllable.


Assuntos
Neoplasias Colorretais , Humanos , Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Cetuximab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/cirurgia , Receptores ErbB/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , Ensaios Clínicos Controlados Aleatórios como Assunto , Metástase Neoplásica
10.
Parasitol Res ; 123(1): 18, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38063934

RESUMO

Toxoplasma gondii is a pathogen that poses a serious threat to human health and causes significant economic losses to the global livestock industry. The prevalence of toxoplasmosis infection has been reported to be high in humans and animals around the world, but the occurrence of the disease has not yet been reported in water buffaloes in Guangxi Zhuang Autonomous Region, southern China. To understand the overall seroprevalence of T. gondii infection in Guangxi, a total of 1041 water buffalo and 114 cat serum samples were examined using an indirect enzyme-linked immunosorbent assay (I-ELISA). Of the 1041 water buffaloes analyzed, an overall seroprevalence of 52.9% (551/1041) was obtained, with year, season, and city location being significant factors affecting the rate of T. gondii infection in water buffaloes (P < 0.001). The results also revealed a high seroprevalence of 57% (65/114) in cats. Given that buffalo milk and meat products are vital food sources, these findings suggest that toxoplasmosis in water buffaloes may be a public health threat. This study provides the first T. gondii seroprevalence data in Guangxi, which could contribute to the prevention and control of toxoplasmosis in the region.


Assuntos
Bison , Toxoplasma , Toxoplasmose Animal , Gatos , Humanos , Animais , Búfalos , Toxoplasmose Animal/epidemiologia , Estudos Soroepidemiológicos , China/epidemiologia , Anticorpos Antiprotozoários , Fatores de Risco
11.
Sensors (Basel) ; 23(7)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37050450

RESUMO

The magnetic field is a vital physical quantity in nature that is closely related to human production life. Magnetic field sensors (namely magnetometers) have significant application value in scientific research, engineering applications, industrial productions, and so forth. Accompanied by the continuous development of magnetic materials and fiber-sensing technology, fiber sensors based on the Magneto-Refractive Effect (MRE) not only take advantage in compact structure, superior performance, and strong environmental adaptability but also further meet the requirement of the quasi-distributed/distributed magnetic field sensing; they manifest potential and great application value in space detection, marine environmental monitoring, etc. Consequently, the present and prevalent Magneto-Refractive Magnetic Field Fiber Sensors (MR-MFSs) are briefly summarized by this paper, proceeding from the perspective of physicochemical properties; design methods, basic performance and properties are introduced systematically as well. Furthermore, this paper also summarizes key fabrication techniques and future development trends of MR-MFSs, expecting to provide ideas and technical references for staff engaging in relevant research.

12.
Sensors (Basel) ; 23(10)2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37430570

RESUMO

In the process of ocean exploration, highly accurate and sensitive measurements of seawater temperature and pressure significantly impact the study of seawater's physical, chemical, and biological processes. In this paper, three different package structures, V-shape, square-shape, and semicircle-shape, are designed and fabricated, and an optical microfiber coupler combined Sagnac loop (OMCSL) is encapsulated in these structures with polydimethylsiloxane (PDMS). Then, the temperature and pressure response characteristics of the OMCSL, under different package structures, are analyzed by simulation and experiment. The experimental results show that structural change hardly affects temperature sensitivity, and square-shape has the highest pressure sensitivity. In addition, with an input error of 1% F.S., temperature and pressure errors were calculated, which shows that a semicircle-shape structure can increase the angle between lines in the sensitivity matrix method (SMM), and reduce the effect of the input error, thus optimizing the ill-conditioned matrix. Finally, this paper shows that using the machine learning method (MLM) effectively improves demodulation accuracy. In conclusion, this paper proposes to optimize the ill-conditioned matrix problem in SMM demodulation by improving sensitivity with structural optimization, which essentially explains the cause of the large errors for multiparameter cross-sensitivity. In addition, this paper proposes to use the MLM to solve the problem of large errors in the SMM, which provides a new method to solve the problem of the ill-conditioned matrix in SMM demodulation. These have practical implications for engineering an all-optical sensor that can be used for detection in the ocean environment.

13.
Nano Lett ; 22(3): 1115-1121, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35099980

RESUMO

Engineering magnetic anisotropy in a ferro- or ferrimagnetic (FM) thin film is crucial in a spintronic device. One way to modify the magnetic anisotropy is through the surface of the FM thin film. Here, we report the emergence of a perpendicular magnetic anisotropy (PMA) induced by interfacial interactions in a heterostructure comprised of a garnet ferrimagnet, Y3Fe5O12 (YIG), and a low-symmetry, high spin-orbit coupling (SOC) transition metal dichalcogenide, WTe2. At the same time, we also observed an enhancement in Gilbert damping in the WTe2-covered YIG area. Both the magnitude of interface-induced PMA and the Gilbert damping enhancement have no observable WTe2 thickness dependence down to a single quadruple layer, indicating that the interfacial interaction plays a critical role. The ability of WTe2 to enhance the PMA in FM thin film, combined with its previously reported capability to generate out-of-plane damping like spin torque, makes it desirable for magnetic memory applications.

14.
Cent Eur J Immunol ; 48(4): 301-310, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38558561

RESUMO

Introduction: A growing number of randomized controlled trials (RCTs) have demonstrated the effectiveness of interleukin (IL)-23 and IL-12/23 inhibitors in treating Crohn's disease (CD). This study evaluated the efficacy of IL-23 and IL-12/23 inhibitors in the induction phase for the treatment of CD. Material and methods: We searched the following databases from inception until December, 2022: Medline, Embase, Web of Science and the Cochrane Library. The primary outcome was the proportion of CD patients who achieved clinical remission at the end of the induction therapy period. Secondary outcomes included clinical response, endoscopic remission, endoscopic response and normalized C-reactive protein (CRP). Results: After screening, 7 RCTs were included in our study. The meta-analysis showed that, in the induction period, more patients treated with IL-23 inhibitors and IL-12/23 inhibitors achieved clinical remission than patients with placebo therapy (RR = 2.11, 95% CI: 1.83-2.44; RR = 1.94, 95% CI: 1.64-2.29; respectively). The IL-23 inhibitor group and the IL-12/23 inhibitor group showed higher clinical response rates than the placebo group (RR = 1.92, 95% CI: 1.74-2,11; RR = 1.83, 95% CI: 1.61-2.09; respectively). In addition, the IL-23 inhibitor group had a higher endoscopic remission rate and endoscopic response rate than the placebo group; the corresponding pooled RRs were 3.40 (95% CI: 2.57-4.50) and 2.65 (95% CI: 2.65-3.12), respectively. Conclusions: IL-23 and IL-12/23 inhibitors were efficient methods in the induction treatment of CD.

15.
Opt Express ; 30(10): 16405-16418, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36221484

RESUMO

A photonic crystal fiber utilizing surface plasmon resonance (PCF-SPR) sensor based on refractive index (RI) control of magnetic fluid (MF) is designed. The air holes of the sensor are arranged in a hexagonal shape, and the optical field transmission channels on both sides of the central air hole can effectively confine the energy of the optical field. We use MF as the sensing medium, and coat the inner wall of the central air hole with gold. It can effectively stimulate the SPR effect to achieve the purpose of magneto-refractive modulation. We study the sensing characteristics of the proposed sensor by finite element analysis. The results show that the highest refractive index sensitivity reaches 19520 nm/RIU in the RI range of 1.42-1.435 and the maximum figure of merit (FOM) is 374.3 RIU-1. In addition, the magnetic field and the temperature response characteristics of the designed sensor are also investigated. In the magnetic field range of 50-130 Oe, the magnetic field sensitivity is 590 pm/Oe. In the temperature range of 24.3-144.3 °C, the temperature sensitivity is only -29.7 pm/℃. The proposed sensor has significant advantages such as stable structure, high sensitivity, easy integration, resistance to electromagnetic interference and can be used for weak magnetic magnitude detection. It has wide application prospects in industrial production, military, and medical equipment.

16.
Opt Express ; 30(23): 41240-41254, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36366606

RESUMO

In order to meet the demand for large-scale magnetic field testing, this paper proposes a D-shaped magneto-refractive photonic crystal fiber (MRPCF) based on surface plasmon resonance (SPR) by using the erbium-doped materials. The four different structures of Models A, B, C, and D are designed by changing the diameter, the position, and the number of layers of the air holes, and the corresponding magnetic field sensing characteristics are analyzed. The results show that in the magnetic field range of 5-405 mT, the magnetic field sensitivities of Models A, B, C, and D are 28 pm/mT, 48 pm/mT, 36 pm/mT, and 21 pm/mT, respectively. Meanwhile, the figure of merit (FOM) of the four MRPCF-SPR sensors is investigated, which have FOMs of 4.8 × 10-4 mT-1, 6.4 × 10-4 mT-1, 1.9 × 10-4 mT-1, 0.9 × 10-4 mT-1. Model B has higher sensitivity and larger FOM. In addition, the effect of the structural parameters of Model B on the sensing performance is also studied. By optimizing each parameter, the magnetic field sensitivity of the optimized Model B is increased to 53 pm/mT, and its magneto-refractive sensitivity and FOM are 2.27 × 10-6 RIU/mT and 6.2 × 10-4 mT-1, respectively. It shows that the magneto-refractive effect of MRPCF can be effectively enhanced by optimizing the structural design of fiber. The proposed MRPCF is an all-solid-state fiber, which solves the instability problem of the magnetic fluid-filled fiber and reduces the complexity of the fabrication process. The all-solid-state MRPCF can be used in the development of quasi-distributed optical fiber magnetic field sensors and has broad applications in the fields of geological exploration, earthquake and tsunami monitoring, and military navigation.

17.
Opt Express ; 30(21): 39055-39067, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36258455

RESUMO

A surface plasmon resonance (SPR) sensor comprising photonic crystal fiber (PCF) is designed for magnetic field and temperature dual-parameter sensing. In order to make the SPR detection of magnetic field and temperature effectively, the two open ring channels of the proposed sensor are coated with gold and silver layers and filled with magnetic fluid (MF) and Polydimethylsiloxane (PDMS), respectively. The sensor is analyzed by the finite element method and its mode characteristics, structure parameters and sensing performance are investigated. The analysis reveals when the magnetic field is a range of 40-310 Oe and the temperature is a range of 0-60 °C, the maximum magnetic field sensitivity is 308.3 pm/Oe and temperature sensitivity is 6520 pm/°C. Furthermore, temperature and magnetic field do not crosstalk with each other's SPR peak. Its refractive index sensing performance is also investigated, the maximum sensitivity and FOM of the left channel sensing are 16820 nm/RIU and 1605 RIU-1, that of the right channel sensing are 13320 nm/RIU and 2277 RIU-1. Because of its high sensitivity and special sensing performance, the proposed sensor will have potential application in solving the problems of cross-sensitivity and demodulation due to nonlinear changes in sensitivity of dual-parameter sensing.

18.
Opt Express ; 30(16): 29271-29286, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36299105

RESUMO

To improve the sensing performance of optical fiber magnetic field sensor based on magneto-refractive effect, a D-shaped photonic crystal fiber-surface plasmon resonance (PCF-SPR) sensor based on magneto-refractive effect is proposed and its magnetic field sensing characteristics are investigated. The designed D-shaped PCF has a core-analyte-gold structure. Within the D-shaped PCF, the side polishing surface is coated with the gold film and the special hole is sandwiched between the core and the gold film. To realize the high magnetic field sensitivity for the fiber SPR magnetic field sensor, the special hole is filled with magnetic fluid (MF). In this paper, we analyze the mode transmission characteristics and magnetic field sensing characteristics of this fiber sensor by finite element method. We also obtain a general rule for the optimization of PCF-SPR sensors by analyzing the dispersion curves, the energy of the surface plasmon polariton mode and the core mode on the sensing performance of the designed fiber sensor. The maximum refractive index sensitivity and magnetic field sensitivity of the optimized fiber are 59714.3 nm/RIU and 21750 pm/mT (50-130 Oe), respectively. Compared with optical fiber magnetic field sensors based on magneto-refractive effect reported previously, the magnetic field sensitivity in this paper is nearly two orders of magnitude higher and it can initially achieve nT magnitude magnetic field resolution and testing capability. The proposed fiber sensor has the advantages of simple structure, easy production, high sensitivity, and strong environmental adaptability. It not only improves the sensing performance of optical fiber magnetic field sensors, but also provides an ideal alternative platform for biosensors like microfluidics because of its high refractive index sensitivity and the special structure.

19.
Phytochem Rev ; 21(1): 239-289, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34093097

RESUMO

Medicinal plants are one of the most important sources of antiviral agents and lead compounds. Lignans are a large class of natural compounds comprising two phenyl propane units. Many of them have demonstrated biological activities, and some of them have even been developed as therapeutic drugs. In this review, 630 lignans, including those obtained from medicinal plants and their chemical derivatives, were systematically reviewed for their antiviral activity and mechanism of action. The compounds discussed herein were published in articles between 1998 and 2020. The articles were identified using both database searches (e.g., Web of Science, Pub Med and Scifinder) using key words such as: antiviral activity, antiviral effects, lignans, HBV, HCV, HIV, HPV, HSV, JEV, SARS-CoV, RSV and influenza A virus, and directed searches of scholarly publisher's websites including ACS, Elsevier, Springer, Thieme, and Wiley. The compounds were classified on their structural characteristics as 1) arylnaphthalene lignans, 2) aryltetralin lignans, 3) dibenzylbutyrolactone lignans, 4) dibenzylbutane lignans, 5) tetrahydrofuranoid and tetrahydrofurofuranoid lignans, 6) benzofuran lignans, 7) neolignans, 8) dibenzocyclooctadiene lignans and homolignans, and 9) norlignans and other lignoids. Details on isolation and antiviral activities of the most active compounds within each class of lignan are discussed in detail, as are studies of synthetic lignans that provide structure-activity relationship information.

20.
Phys Chem Chem Phys ; 24(35): 21233-21241, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36040374

RESUMO

In this paper, a dual-parameter sensor based on surface plasmon resonance (SPR)-photonic crystal fiber (PCF) is proposed, which can be applied in detecting the magnetic field and temperature. In this sensor, two elliptical channels are designed on both sides of the fiber core. The left channel (Ch 1) is coated with gold film and filled with magnetic fluid (MF) to achieve a response to the magnetic field and temperature using SPR. The right channel (Ch 2) is coated with gold film as well as Ta2O5 film to improve the SPR sensing performance. Finally, Ch 2 is filled with polydimethylsiloxane (PDMS) to achieve a response to the temperature. The mode characteristics, structural parameters and sensing performance are investigated by the finite element method. The results show that when the magnetic field is in the range of 50-130 Oe, the magnetic field sensitivities of Ch 1 and Ch 2 are 65 pm Oe-1 and 0 pm Oe-1, respectively. When the temperature is in the range of 17.5-27.5 °C, the temperature sensitivities of Ch 1 and Ch 2 are 520 pm °C-1 and 2360 pm °C-1, respectively. By establishing and demodulating a sensing matrix, the sensor can not only measure the temperature and magnetic field simultaneously but also solve the temperature cross-sensitivity problem. In addition, when the temperature exceeds a certain value, the proposed sensor is expected to achieve dual-parameter sensing without a matrix. The proposed dual-parameter SPR-PCF sensor has a unique structure and excellent sensing performance, which are important for the simultaneous sensing of multiple basic physical parameters.

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