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1.
Zhongguo Gu Shang ; 37(4): 368-73, 2024 Apr 25.
Article in Chinese | MEDLINE | ID: mdl-38664207

ABSTRACT

OBJECTIVE: To investigate the effect of electroacupuncture therapy on postoperative rehabilitation training of patients with knee fractures. METHODS: Patients with knee fractures from July 2020 to July 2021 were randomly assigned to either the experimental group or a control group according to the double-blind principle. Both groups were given surgical treatment and postoperative conventional rehabilitation training. There were 40 cases in the control group, including 27 males and 13 females;the age ranged from 20 to 66 years old with an average of (36.46±6.29) years old, continuous passive motion (CPM) training was performed after operation. There were 40 patients in the experimental group, including 24 males and 16 females. The age ranged from 21 to 68 years old with an average of (37.62±7.08) years old, on the basis of the control group, electroacupuncture was given. After 4 weeks of intervention, the excellent rate of knee function score, visual analogue scale (VAS) before and after intervention, serum pain mediators, prostaglandin E (PGE), substance P (SP), bradykinin (BK), joint range of motion and quality of life were compared between the two groups. RESULTS: After 4 weeks of intervention, the Rasmussen score for knee function in the experimental group (24.15±1.36) scores was higher than that in the control group (21.25±2.20) scores (P<0.001). The VAS in the experimental group (2.04±0.51) scores was lower than that in the control group (2.78±0.60) after 4 weeks of intervention (P<0.05). Serum PGE (2.25±0.37) mg·L-1, SP (4.43±1.05) ng·ml-1, BK (2.67±0.68) ng·ml-1 in the experimental group were lower than those in the control group (3.91±0.44) mg·L-1, (6.12±1.37) ng·ml-1, (4.55±1.03) ng·ml-1 after 4 weeks of intervention(P<0.05);in the experimental group, the active knee flexion angle of the knee joint was (108.63±9.76)°, the active knee extension angle (-2.46±0.70)°, passive knee flexion angle (116.83±6.57)°, passive knee extension angle (1.44±0.38)° were better than control group (100.24±8.15)°, (-3.51±0.86)°, (111.04±8.22)°, (0.78±0.24)° (P<0.05);the experimental group's psychological score (73.12±5.08), physiological score (72.26±5.89), social function score (72.57±4.23), overall health score (75.12±5.16) were higher than that of the control group (68.49±4.13), (68.13±5.27), (69.04±3.42), and(70.88±3.97) respectvely(P<0.05). CONCLUSION: Electroacupuncture combined with CPM training after knee fracture surgery can significantly improve knee function and range of motion, reduce pain levels, and also improve quality of life and reduce the incidence of adverse events.


Subject(s)
Electroacupuncture , Humans , Male , Electroacupuncture/methods , Female , Middle Aged , Adult , Aged , Range of Motion, Articular , Young Adult , Quality of Life , Postoperative Period , Knee Injuries/surgery , Knee Injuries/rehabilitation , Knee Joint/surgery , Substance P/blood , Double-Blind Method , Fractures, Bone/surgery , Fractures, Bone/therapy , Knee Fractures
3.
Huan Jing Ke Xue ; 44(12): 6823-6832, 2023 Dec 08.
Article in Chinese | MEDLINE | ID: mdl-38098407

ABSTRACT

Using diammonium hydrogen phosphate as an activator and N and P source and and bamboo chips as the carbon source, N, P co-doped activated carbon was prepared by one-step pyrolysis and used to efficiently remove La3+ in aqueous solutions. The effects of activation temperature and pH value on the adsorption performance of La3+ were analyzed, and the activation and adsorption mechanisms were explored using TG-IR, SEM-EDX, pore structure, XPS, and hydrophilicity. The results showed that diammonium hydrogen phosphate easily decomposed at a high temperature to produce ammonia and phosphoric acid, which activated the material and promoted the increase in the specific surface area and pore volume of the activated carbon. As an N and P source, the addition of diammonium hydrogen phosphate successfully achieved the N, P co-doping of activated carbon, and the introduction of N- and P-containing functional groups was the key to enhance the adsorption of La3+. Among them, graphitic nitrogen could provide interactions between La3+-π bonds, and C-P=O and C/P-O-P could provide active sites for the adsorption of La3+ through complexation and electrostatic interaction. The adsorption of La3+ on N, P co-doped activated carbons was endothermic and spontaneous, and the adsorption process conformed to the Langmuir isotherm and secondary kinetic model. Under the process conditions of an activation temperature of 900℃ and pH=6, the adsorption capacity of the N, P co-doped activated carbon was as high as 55.18 mg·g-1, which was 2.53 times higher than that of the undoped sample, and its adsorption selectivity for La3+ in the La3+/Na+and La3+/Ca2+ coexistence systems reached 93.49% and 82.49%, respectively. Additionally, the removal efficiency remained above 54% after five successive adsorption-desorption cycle experiments.

4.
Huan Jing Ke Xue ; 44(6): 3142-3151, 2023 Jun 08.
Article in Chinese | MEDLINE | ID: mdl-37309933

ABSTRACT

In order to understand the current status of main chemical components of atmospheric precipitation in Xi'an, the pH, electrical conductivity, mass concentration of water-soluble ions and heavy metals, wet deposition fluxes, and their sources in precipitation samples in urban and suburban areas of Xi'an in 2019 were studied. The results showed that the pH, conductivity, water-soluble ions, and heavy metals in precipitation in Xi'an in winter were higher than those in other seasons. The main water-soluble ions in precipitation were Ca2+, NH+4, SO2-4, and NO-3, and the sum of these ions accounted for (88.5%±2.8)% of the total ion concentration in urban and suburban areas. The main heavy metals were Zn, Fe, and Zn and Mn; their sum accounted for (54.0%±3)% and (47.0%±8)% of the total metal concentration. The wet deposition fluxes of water-soluble ions in precipitation in urban and suburban areas were (253.2±58.4) mg·(m2·month)-1 and (241.9±61.1) mg·(m2·month)-1, respectively. They showed higher values in winter than those in other seasons. The wet deposition fluxes of heavy metals were (86.2±37.5) mg·(m2·month)-1 and (88.1±37.4) mg·(m2·month)-1, respectively, with little seasonal difference. The source analysis using PMF showed that the water-soluble ions in urban and suburban precipitation mainly came from combustion sources (57.5% and 32.32%), followed by motor vehicles (24.4% and 17.2%) and dust sources (18.1% and 27.0%). The ions in suburban precipitation were also affected by local agriculture (11.1%). Heavy metals in precipitation in urban and suburban areas mainly came from industrial sources (51.8% and 46.7%), and the contribution rate of coal and motor vehicle mixed sources in winter was 10.7% and 6.1% higher than that in summer, respectively.

5.
Front Bioeng Biotechnol ; 11: 1056707, 2023.
Article in English | MEDLINE | ID: mdl-36873351

ABSTRACT

Background: The treatment of bone defects remains a clinical challenge. The effect of negative pressure wound therapy (NPWT) on osteogenesis in bone defects has been recognized; however, bone marrow fluid dynamics under negative pressure (NP) remain unknown. In this study, we aimed to examine the marrow fluid mechanics within trabeculae by computational fluid dynamics (CFD), and to verify osteogenic gene expression, osteogenic differentiation to investigate the osteogenic depth under NP. Methods: The human femoral head is scanned using micro-CT to segment the volume of interest (VOI) trabeculae. The VOI trabeculae CFD model simulating the bone marrow cavity is developed by combining the Hypermesh and ANSYS software. The effect of trabecular anisotropy is investigated, and bone regeneration effects are simulated under NP scales of -80, -120, -160, and -200 mmHg. The working distance (WD) is proposed to describe the suction depth of the NP. Finally, gene sequence analysis, cytological experiments including bone mesenchymal stem cells (BMSCs) proliferation and osteogenic differentiation are conducted after the BMSCs are cultured under the same NP scale. Results: The pressure, shear stress on trabeculae, and marrow fluid velocity decrease exponentially with an increase in WD. The hydromechanics of fluid at any WD inside the marrow cavity can be theoretically quantified. The NP scale significantly affects the fluid properties, especially those fluid close to the NP source; however, the effect of the NP scale become marginal as WD deepens. Anisotropy of trabecular structure coupled with the anisotropic hydrodynamic behavior of bone marrow; An NP of -120 mmHg demonstrates the majority of bone formation-related genes, as well as the most effective proliferation and osteogenic differentiation of BMSCs compared to the other NP scales. Conclusion: An NP of -120 mmHg may have the optimal activated ability to promote osteogenesis, but the effective WD may be limited to a certain depth. These findings help improve the understanding of fluid mechanisms behind NPWT in treating bone defects.

6.
J Natl Cancer Inst ; 115(6): 742-748, 2023 06 08.
Article in English | MEDLINE | ID: mdl-35094066

ABSTRACT

BACKGROUND: Adding radiotherapy (RT) to systemic therapy improves progression-free survival (PFS) and overall survival (OS) in oligometastatic non-small cell lung cancer (NSCLC). Whether these findings translate to epidermal growth factor receptor (EGFR)-mutated NSCLC remains unknown. The SINDAS trial (NCT02893332) evaluated first-line tyrosine kinase inhibitor (TKI) therapy for EGFR-mutated synchronous oligometastatic NSCLC and randomized to upfront RT vs no RT; we now report the prespecified interim analysis at 68% accrual. METHODS: Inclusion criteria were biopsy-proven EGFR-mutated adenocarcinoma (per amplification refractory mutation system or next generation sequencing), with synchronous (newly diagnosed, treatment naïve) oligometastatic (≤5 metastases; ≤2 lesions in any one organ) NSCLC without brain metastases. All patients received a first-generation TKI (gefitinib, erlotinib, or icotinib), and randomization was between no RT vs RT (25-40 Gy in 5 fractions depending on tumor size and location) to all metastases and the primary tumor/involved regional lymphatics. The primary endpoint (intention to treat) was PFS. Secondary endpoints included OS and toxicities. All statistical tests were 2-sided. RESULTS: A total of 133 patients (n = 65 TKI only, n = 68 TKI with RT) were enrolled (2016-2019). The median follow-up was 23.6 months. The respective median PFS was 12.5 months vs 20.2 months (P < .001), and the median OS was 17.4 months vs 25.5 months (P < .001) for TKI only vs TKI with RT. Treatment yielded no grade 5 events and a 6% rate of symptomatic grade 3-4 pneumonitis in the TKI with RT arm. Based on the efficacy results of this prespecified interim analysis, the ethics committee recommended premature cessation of this trial. CONCLUSIONS: As compared with a first-line TKI alone, addition of upfront local therapy using RT statistically significantly improved PFS and OS for EGFR-mutated NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/radiotherapy , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/radiotherapy , Protein Kinase Inhibitors/adverse effects , ErbB Receptors/genetics , Mutation
7.
Nutr Metab Cardiovasc Dis ; 31(10): 2912-2920, 2021 09 22.
Article in English | MEDLINE | ID: mdl-34454825

ABSTRACT

BACKGROUND AND AIMS: Increased serum uric acid (SUA) is common in type 2 diabetes mellitus (T2DM) and is associated with left ventricular (LV) myocardial dysfunction. Nonetheless the association of SUA with right ventricular (RV) function in T2DM has not been studied. This study aimed to investigate the association of SUA with biventricular myocardial function in patients with T2DM. METHODS AND RESULTS: A total of 560 patients with T2DM were enrolled and divided into four groups according to sex-specific quartiles of SUA. Transthoracic echocardiography was performed and two-dimensional speckle tracking was used to measure biventricular myocardial strain, including LV global longitudinal strain (GLS), circumferential strain (CS), radial strain (RS), and RV free wall longitudinal strain (RV-FWLS). The absolute value of all biventricular strain parameters showed a stepwise decrease across SUA quartiles (all P < 0.01). In particular, LV assessment by GLS, CS and RS demonstrated that those in the 4th quartile were impaired compared with the other quartiles (all P < 0.05). Similarly, RV-FWLS of the 4th quartile was significantly impaired compared with the 1st and 2nd quartiles (all P < 0.05). The same reduction in biventricular strain across SUA quartiles was observed in patients with estimated glomerular filtration rate < or ≥60 ml/min/1.73 m2, and glycated hemoglobin < or ≥7.0% (all P < 0.05). Multivariable linear regression analysis demonstrated that higher quartile of SUA was independently associated with impaired biventricular myocardial strain (all P < 0.05). CONCLUSIONS: SUA was independently associated with biventricular myocardial dysfunction in asymptomatic T2DM patients, regardless of renal function or diabetic control.


Subject(s)
Diabetes Mellitus, Type 2/epidemiology , Hyperuricemia/epidemiology , Uric Acid/blood , Ventricular Dysfunction, Left/epidemiology , Ventricular Dysfunction, Right/epidemiology , Aged , Biomarkers/blood , Cross-Sectional Studies , Diabetes Mellitus, Type 2/diagnosis , Echocardiography , Female , Hong Kong/epidemiology , Humans , Hyperuricemia/blood , Hyperuricemia/diagnosis , Male , Middle Aged , Prevalence , Prognosis , Risk Assessment , Risk Factors , Sex Factors , Ventricular Dysfunction, Left/diagnostic imaging , Ventricular Dysfunction, Left/physiopathology , Ventricular Dysfunction, Right/diagnostic imaging , Ventricular Dysfunction, Right/physiopathology , Ventricular Function, Left , Ventricular Function, Right
8.
aBIOTECH ; 2(1): 64-78, 2021 Mar.
Article in English | MEDLINE | ID: mdl-36304478

ABSTRACT

The molecular mechanism of the maintenance and differentiation of plant stem cells is an eternal theme in studies on plant growth and development. Recent advances in single-cell RNA sequencing (scRNA-seq) methods have completely changed the understanding of cell heterogeneity and cell function, allowing research precision to identify the differentiation trajectory of stem cells maintained and differentiated at the cellular level. This review aimed to mainly discuss the novel insights provided by scRNA-seq for the maintenance and initiation of plant stem cells, cell differentiation, cell response to environmental changes, and improvement strategies for scRNA-seq. In addition, it highlighted additional perspectives beyond scRNA-seq, such as spatial transcriptomes, epigenomes, and single-cell multiomics, for a renewed understanding of stem cell maintenance and cell differentiation, thus providing potential targets and theoretical foundations for crop improvement.

9.
Plant Cell Rep ; 40(2): 271-282, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33025178

ABSTRACT

KEY MESSAGE: Cytokinins are a class of phytohormone that participate in the regulation of the plant growth, development, and stress response. In this review, the potential regulating mechanism during plant growth and stress response are discussed. Cytokinins are a class of phytohormone that participate in the regulation of plant growth, physiological activities, and yield. Cytokinins also play a key role in response to abiotic stresses, such as drought, salt and high or low temperature. Through the signal transduction pathway, cytokinins interact with various transcription factors via a series of phosphorylation cascades to regulate cytokinin-target gene expression. In this review, we systematically summarize the biosynthesis and metabolism of cytokinins, cytokinin signaling, and associated gene regulation, and highlight the function of cytokinins during plant development and resistance to abiotic stress. We also focus on the importance of crosstalk between cytokinins and other classes of phytohormones, including auxin, ethylene, strigolactone, and gibberellin. Our aim is to provide a comprehensive overview of recent findings on the mechanisms by which cytokinins act as central regulators of plant development and stress reactions, and highlight topics for future research.


Subject(s)
Cytokinins/metabolism , Plant Growth Regulators/metabolism , Plants/genetics , Signal Transduction , Gene Expression Regulation, Plant , Gibberellins/metabolism , Indoleacetic Acids/metabolism , Plant Development , Plant Physiological Phenomena , Stress, Physiological
10.
Saudi J Biol Sci ; 26(5): 1032-1036, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31303837

ABSTRACT

mtDNA COII gene sequences were identified and analyzed using different types of software, namely, MEGA5.0, DNAMAN, and DnaSP5.0 in four Chinese provinces, namely, Sichuan, Zhejiang, Guizhou and Shanghai. Analysis of molecular genetic variation and its genetic structure and differentiation, combined with NJ tree, MP tree analysis and analysis of molecular variance (AMOVA), at Fst = 0.0582 conclude that the genetic differentiation is low, gene flow is Nm = 8.0911, and gene exchange is sufficient. However, for the geographic populations of Pseudoregma bambucicola in the four provinces, their gene exchange is relatively weak at Nm = 0.8284, whereas the genetic differentiation is high at Fst = 0.3764. Based on the data, total nucleotide diversity between the populations is 0.00158 ±â€¯0.00021. The results showed that the total population of Tajima's D and Fu's Fs results are D = -0.885 and Fs = 0.226, respectively. The experimental numerical results showed that this total population is not significant (P > 0.10), indicating that nine different geographic populations are short-term. No expansion occurred in the internal population. This study provided a theoretical and practical basis for the comprehensive prevention and control of P. bambucicola.

11.
Nanoscale Adv ; 1(4): 1452-1459, 2019 Apr 09.
Article in English | MEDLINE | ID: mdl-36132596

ABSTRACT

Terahertz electromagnetic (EM) wave absorbers are vital in photonics, however, they suffer from limited bandwidth. A new approach for ultra-wideband (UWB) terahertz absorber design is proposed with metal and graphene metasurfaces. The UWB characteristics are owing to three factors: (1) the metal metasurface boosts the surface plasmon-polaritons (SPPs) of the graphene metasurface which leads to confined field enhancement, (2) the merging and interaction of the resonances of the metal and graphene metasurfaces, and (3) the multiple reflections and superpositions between the metasurfaces and the gold layer. A prototype designed using a dual-ring metal metasurface, fishnet graphene metasurface, polyimide substrate and gold reflecting layer is proposed. One cell of the prototype includes one metal dual-ring unit and four graphene fishnet units. The proposed absorber has an UWB bandwidth of 6.46 THz (145%) for absorptivity larger than 0.9, with a high octave of 6.21. The proposed absorber is also insensitive to the polarization state and incident angle of the illuminating EM waves. Besides, the amplitude modulation depth in the 5-6 THz band is up to 95.4%. The physical mechanisms of the wideband operation are also discussed. The research in this work could offer a new thought for UWB absorber design, and has potential applications in terahertz imaging, sensors, photodetectors and modulators (e.g. [L. Peng, X. M. Li, X. Liu, X. Jiang and S. M. Li, Nanoscale Adv., 2000, 35, 3523]).

12.
Nanoscale Res Lett ; 13(1): 385, 2018 Nov 29.
Article in English | MEDLINE | ID: mdl-30499041

ABSTRACT

Terahertz electromagnetic (EM) wave components usually have a single function, such as they can only convert the polarization state of an incident wave or absorb the incident energy, which would be a limitation for their applications. To make a breakthrough, a multi-functional device (MFD) is proposed in this paper, and it is capable of switching between absorption mode and polarization conversion mode. The device has a low-profile and simple structure, and it is constructed by graphene-based absorbing metasurface (AM) and gold-based polarization conversion metasurface (PCM). By controlling the chemical potential (µc) of the graphene, the leading role is transferred between the AM and the PCM, which leads to steerable absorption and polarization conversion (PC) modes. For the PC mode, the simulated polarization conversion ratio (PCR) is larger than 0.9 in the 2.11-3.63-THz band (53.0% at 2.87 THz). For the absorption mode, the simulated absorptivity is larger than 80% in the 1.59-4.54-THz band (96.4% at 3.06 THz). The physical mechanisms and operating characteristics of the MFD are discussed. This research has potential applications in terahertz imaging, sensors, photodetectors, and modulators.

13.
Sensors (Basel) ; 16(12)2016 Dec 09.
Article in English | MEDLINE | ID: mdl-27941702

ABSTRACT

In this research, the novel concept of a resonance-based reflector (RBR) was proposed, and a ring-shaped RBR was utilized to design a unidirectional antenna with low-profile and broadband characteristics. Research found the ring operates as two half-wavelength (λ/2) resonators. Then, the resonance effect transforms the reflection phase of the ring RBR, and achieves a reflection phase of 0° < ϕ < 180° in a wide frequency range above the resonance. Then, the in-phase reflection characteristic (-90° < ϕ < 90°) can be obtained in the wide frequency band by placing an antenna above the RBR with a distance smaller than λ/4. Two unidirectional antennas, named Case 1 and Case 2, were designed with the ring-shaped RBRs and bowtie antennas (RBR-BAs). The impedance bandwidths of Case 1 and the Case 2 are 2.04-5.12 GHz (86.3%) and 1.97-5.01 GHz (87.1%), respectively. The front-to-back ratio (FBR, an important parameter to measure the unidirectional radiation) of Case 1 ranges from 5-9.9 dB for frequencies 2.04-2.42 GHz, and the FBR of Case 2 ranges from 5-16 dB for frequencies 2.16-3.15 GHz. The proposed concept of RBR is desirable in wideband unidirectional antenna design, and the designing antennas can be used at the front end of wireless systems-such as indoors communication, remote sensing, and wireless sensor systems-for signal receiving or transmitting.

14.
Sensors (Basel) ; 16(6)2016 Jun 09.
Article in English | MEDLINE | ID: mdl-27294928

ABSTRACT

Existing spectrum-sensing techniques for cognitive radios require an analog-to-digital converter (ADC) to work at high dynamic range and a high sampling rate, resulting in high cost. Therefore, in this paper, a spectrum-sensing method based on a unidirectionally coupled, overdamped nonlinear oscillator ring is proposed. First, the numerical model of such a system is established based on the circuit of the nonlinear oscillator. Through numerical analysis of the model, the critical condition of the system's starting oscillation is determined, and the simulation results of the system's response to Gaussian white noise and periodic signal are presented. The results show that once the radio signal is input into the system, it starts oscillating when in the critical region, and the oscillating frequency of each element is fo/N, where fo is the frequency of the radio signal and N is the number of elements in the ring. The oscillation indicates that the spectrum resources at fo are occupied. At the same time, the sampling rate required for an ADC is reduced to the original value, 1/N. A prototypical circuit to verify the functionality of the system is designed, and the sensing bandwidth of the system is measured.

15.
Opt Express ; 23(20): 26586-95, 2015 Oct 05.
Article in English | MEDLINE | ID: mdl-26480171

ABSTRACT

We present a generalized Poincaré sphere (G sphere) and generalized Stokes parameters (G parameters), as a geometric representation, which unifies the descriptors of a variety of vector fields. Unlike the standard Poincaré sphere, the radial dimension in the G sphere is not used to describe the partially polarized field. The G sphere is constructed by extending the basic Jones vector bases to the general vector bases with the continuously changeable ellipticity (spin angular momentum, SAM) and the higher dimensional orbital angular momentum (OAM). The north and south poles of different spherical shells in the G sphere represent the pair of different orthogonal vector basis with different ellipticity (SAM) and the opposite OAM. The higher-order Poincaré spheres are just the two special spherical shells of the G sphere. We present a quite flexible scheme, which can generate all the vector fields described in the G sphere.

16.
Biomed Rep ; 3(4): 533-536, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26171161

ABSTRACT

The development of hypertension is closely associated with cardiac hypertrophy and apoptosis, and caspase-3, -8 and -9 are key enzymes of apoptosis. The aim of the present study was to evaluate the effects of valsartan on left ventricle hypertrophy and myocardial apoptosis in spontaneously hypertensive rats (SHRs) and to explore the mechanisms for valsartan against apoptosis. A total of 15 SHRs (16 weeks old) were randomly divided into two groups. The SHRs in the valsartan (n=8) and SHR groups (n=7) were fed with valsartan and distilled water for 8 weeks, respectively. Wistar-Kyoto rats (n=8) were the control group. At the end of the experiments, blood pressure, parameters regarding hypertrophy, apoptosis and activities of caspase-3, -8 and -9 were measured. The results showed that valsartan significantly reduced systolic blood pressure and left ventricular hypertrophy, improved left ventricular remodeling, attenuated the myocardial damage and apoptosis, and decreased the activities of caspase-3, -8 and -9 in SHRs. In conclusion, valsartan is able to reverse hypertension-induced left ventricle remodeling, which is associated with, at least in part, its inhibitory effect on myocardial apoptosis in the death receptor-mediated extrinsic, as well as the mitochondrial-mediated intrinsic pathways.

17.
Rev Sci Instrum ; 86(1): 014705, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25638106

ABSTRACT

We propose a synthesis method to design a 90° bent fair circular waveguide TE01 mode transition based on the non-uniform rational B-spline technique. The transition by this method has advantages of small geometry, high transmission with wide band and high profile fairness. An example of design of such a transition is presented. The simulation shows that the transition exhibits a transmission as high as 99.3% at the central frequency 35 GHz and has a bandwidth of 16.7% when keeping the transmission over 95%. Furthermore, the profile is extremely fair, which meets the requirements to decrease the geometry errors between actual device and its design, to reduce the machining difficulty in the machining process. The hot test data indicate that good transmission of the TE01 mode is obtained.

18.
Opt Express ; 22(16): 19302-13, 2014 Aug 11.
Article in English | MEDLINE | ID: mdl-25321015

ABSTRACT

We present in principle and demonstrate experimentally a new kind of vector fields: elliptic-symmetry vector optical fields. This is a significant development in vector fields, as this breaks the cylindrical symmetry and enriches the family of vector fields. Due to the presence of an additional degrees of freedom, which is the interval between the foci in the elliptic coordinate system, the elliptic-symmetry vector fields are more flexible than the cylindrical vector fields for controlling the spatial structure of polarization and for engineering the focusing fields. The elliptic-symmetry vector fields can find many specific applications from optical trapping to optical machining and so on.

19.
Opt Lett ; 38(18): 3700-3, 2013 Sep 15.
Article in English | MEDLINE | ID: mdl-24104851

ABSTRACT

We focus on a new kind of vector optical field with bipolar symmetry of linear polarization instead of cylindrical and elliptical symmetries, enriching members of family of vector optical fields. We design theoretically and generate experimentally the demanded vector optical fields and then explore some novel tightly focusing properties. The geometric configurations of states of polarization provide additional degrees of freedom assisting in engineering the field distribution at the focus to the specific applications such as lithography, optical trapping, and material processing.

20.
Opt Express ; 21(13): 16200-9, 2013 Jul 01.
Article in English | MEDLINE | ID: mdl-23842405

ABSTRACT

We present, design and generate a new kind of vector optical fields with linear polarization distributions modeling to electric and magnetic field lines. The geometric configurations of "electric charges" and "magnetic charges" can engineer the spatial structure and symmetry of polarizations of vector optical field, providing additional degrees of freedom assisting in controlling the field symmetry at the focus and allowing engineering of the field distribution at the focus to the specific applications.

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