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  1. Article ; Online: Group velocity of light in internal conical refraction.

    Wang, Pengqian

    Applied optics

    2023  Volume 62, Issue 16, Page(s) 4310–4320

    Abstract: We calculated the group velocity of light in internal conical refraction in a biaxial crystal as a function of the direction of the electric displacement vector, or the vibration direction, of its carrier wave. Our method represents group velocity ... ...

    Abstract We calculated the group velocity of light in internal conical refraction in a biaxial crystal as a function of the direction of the electric displacement vector, or the vibration direction, of its carrier wave. Our method represents group velocity through the electromagnetic fields of light, rather than its wave normal or ray direction. The travel time of a light pulse traversing a parallel plate biaxial crystal in internal conical refraction is found to vary as a sinusoidal function of twice the vibration angle of the light wave. Our method distinguishes the four directions of the two optic axes in monoclinic and triclinic crystals. Numerical examples are given for
    Language English
    Publishing date 2023-09-14
    Publishing country United States
    Document type Journal Article
    ISSN 1539-4522
    ISSN (online) 1539-4522
    DOI 10.1364/AO.491802
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Polarization-dependent group velocity of light pulses traveling in the optic ray axis directions of a biaxial crystal.

    Wang, Pengqian

    Optics letters

    2022  Volume 47, Issue 9, Page(s) 2338–2341

    Abstract: We theoretically prove that the group velocity of a light pulse traveling in an optic ray axis direction of a biaxial crystal depends on the polarization state of the light. Our calculation shows that the group index varies as a sinusoidal function of ... ...

    Abstract We theoretically prove that the group velocity of a light pulse traveling in an optic ray axis direction of a biaxial crystal depends on the polarization state of the light. Our calculation shows that the group index varies as a sinusoidal function of twice the polarization angle of the light pulse. For monoclinic and triclinic crystals, in general the four directions of the two optic ray axes need to be distinguished. Numerical examples show that in KNbO
    Language English
    Publishing date 2022-04-29
    Publishing country United States
    Document type Journal Article
    ISSN 1539-4794
    ISSN (online) 1539-4794
    DOI 10.1364/OL.459310
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Asymmetry of the group velocity of light in monoclinic crystals.

    Wang, Pengqian

    Optics letters

    2021  Volume 46, Issue 6, Page(s) 1425–1428

    Abstract: We have proved that compared to phase velocity and ray velocity surfaces, the group velocity surface of a monoclinic crystal has a reduced symmetry, due to the loss of the two mirror planes that contain the ... ...

    Abstract We have proved that compared to phase velocity and ray velocity surfaces, the group velocity surface of a monoclinic crystal has a reduced symmetry, due to the loss of the two mirror planes that contain the crystallographic
    Language English
    Publishing date 2021-02-26
    Publishing country United States
    Document type Journal Article
    ISSN 1539-4794
    ISSN (online) 1539-4794
    DOI 10.1364/OL.420414
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Group velocity of light in biaxial crystals.

    Wang, Pengqian

    Applied optics

    2021  Volume 60, Issue 14, Page(s) 4143–4153

    Abstract: Based on the wave vector surface, we have derived the analytical expressions for the group velocity of light traveling in an optically biaxial crystal in an arbitrary direction. Our formulas are in terms of either the wave vector direction or the ray ... ...

    Abstract Based on the wave vector surface, we have derived the analytical expressions for the group velocity of light traveling in an optically biaxial crystal in an arbitrary direction. Our formulas are in terms of either the wave vector direction or the ray direction. An axis dispersion vector is introduced to specify the rotation of the dielectric frame in monoclinic and triclinic crystals, which is found to be responsible for the asymmetry of the group velocity surfaces of these two crystal systems when compared to their phase and ray velocity surfaces. Our formulas confirm that the group velocity of light in a nondissipative medium equals the ratio between the Poynting vector and the total energy density of the electromagnetic field. The group index of light is found to be decomposable into three parts: the ray index, the group index due to principal refractive index dispersion, and that due to axis dispersion. Numerical calculations are performed for the group velocity of light in ${\rm Sn}_2{\rm P}_2{\rm S}_6$ crystal at 550 nm wavelength. Our results show that the dispersion of the principal refractive indices has a considerable contribution to the group index.
    Language English
    Publishing date 2021-05-13
    Publishing country United States
    Document type Journal Article
    ISSN 1539-4522
    ISSN (online) 1539-4522
    DOI 10.1364/AO.423934
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Group velocity of light in uniaxial crystals.

    Wang, Pengqian

    Applied optics

    2021  Volume 60, Issue 7, Page(s) 1987–1994

    Abstract: Using the wave vector surface, we have derived the analytical expressions for the group velocities of the extraordinary light and the ordinary light traveling in an optically uniaxial crystal. Our formulas are in terms of either the wavevector direction ... ...

    Abstract Using the wave vector surface, we have derived the analytical expressions for the group velocities of the extraordinary light and the ordinary light traveling in an optically uniaxial crystal. Our formulas are in terms of either the wavevector direction or the ray direction, and they use only the principal refractive indices and their frequency dispersions. The algebraic equation for the group velocity surface of the crystal is also derived. While the group velocity is in the same direction as the ray velocity, numerical calculation shows that in the visible region the group velocity is slower than the ray velocity, and the difference between them becomes significant at short wavelengths.
    Language English
    Publishing date 2021-03-09
    Publishing country United States
    Document type Journal Article
    ISSN 1539-4522
    ISSN (online) 1539-4522
    DOI 10.1364/AO.416686
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Non-refracted extraordinary rays in a uniaxial crystal.

    Wang, Pengqian

    Applied optics

    2019  Volume 58, Issue 4, Page(s) 883–891

    Abstract: We theoretically investigate non-refracted extraordinary rays where the ray does not change its direction when transmitted from a vacuum into a uniaxial crystal, even at oblique incidence. This is possible only when the optic axis is in the plane of ... ...

    Abstract We theoretically investigate non-refracted extraordinary rays where the ray does not change its direction when transmitted from a vacuum into a uniaxial crystal, even at oblique incidence. This is possible only when the optic axis is in the plane of incidence. We find that within the usual birefringence range of n
    Language English
    Publishing date 2019-03-15
    Publishing country United States
    Document type Journal Article
    ISSN 1539-4522
    ISSN (online) 1539-4522
    DOI 10.1364/AO.58.000883
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Ray refraction in uniaxial crystals by Fermat's principle.

    Wang, Pengqian

    Applied optics

    2018  Volume 57, Issue 18, Page(s) 4950–4954

    Abstract: Fermat's principle is used to study the refraction of extraordinary rays into and out of uniaxial crystals with arbitrary optic axis orientations. The method produces direct formulas for the direction cosines of the refracted rays without the need of ... ...

    Abstract Fermat's principle is used to study the refraction of extraordinary rays into and out of uniaxial crystals with arbitrary optic axis orientations. The method produces direct formulas for the direction cosines of the refracted rays without the need of calculating intermediate quantities. The formulas are validated by comparing them with previous ray-tracing methods.
    Language English
    Publishing date 2018-08-21
    Publishing country United States
    Document type Journal Article
    ISSN 1539-4522
    ISSN (online) 1539-4522
    DOI 10.1364/AO.57.004950
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Geometrical ray tracing in uniaxial crystals: direct formulas and the equivalence between the electromagnetic wave method and Huygens' principle.

    Wang, Pengqian

    Journal of the Optical Society of America. A, Optics, image science, and vision

    2018  Volume 35, Issue 7, Page(s) 1114–1123

    Abstract: Using the electromagnetic wave method and Huygens' principle, we have studied light refraction and reflection on the boundary between two uniaxial crystals with arbitrary optic axis orientations. We provide a set of direct formulas that calculate the ... ...

    Abstract Using the electromagnetic wave method and Huygens' principle, we have studied light refraction and reflection on the boundary between two uniaxial crystals with arbitrary optic axis orientations. We provide a set of direct formulas that calculate the directions of the refracted and reflected extraordinary rays and their associated waves, as well as the ray indices and refractive indices. The formulas use only the initial input variables and do not require the calculation of intermediate quantities. Refraction and reflection are combined in one formula. We also prove that the electromagnetic wave method and Huygens' principle produce analytically equivalent results for geometrical ray tracing.
    Language English
    Publishing date 2018-08-15
    Publishing country United States
    Document type Journal Article
    ZDB-ID 283633-6
    ISSN 1520-8532 ; 1084-7529 ; 0740-3232
    ISSN (online) 1520-8532
    ISSN 1084-7529 ; 0740-3232
    DOI 10.1364/JOSAA.35.001114
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    Zs.B 2689: Show issues Location:
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  9. Article: [Review and prospect of traditional Chinese medicine in treatment of hypertension].

    Xiong, Xing-Jiang / Wang, Peng-Qian / Yao, Kui-Wu / Hou, Jing-le

    Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica

    2024  Volume 48, Issue 24, Page(s) 6592–6599

    Abstract: Hypertension, a primary cause of cardiovascular and cerebrovascular events, has become a major global public health problem and caused a heavy burden of health economics on the society. In "the 20 Most Important and Most Preventable Health Problems" ... ...

    Abstract Hypertension, a primary cause of cardiovascular and cerebrovascular events, has become a major global public health problem and caused a heavy burden of health economics on the society. In "the 20 Most Important and Most Preventable Health Problems" released by the Chinese Academy of Engineering, hypertension was ranked the second. Due to the disease complexity, many hypertension patients need to take antihypertensive drugs for life. Although significant progress has been achieved in blood pressure lowering by western medicines, the problems including adverse reactions, poor compliance due to long-term medication, and ineffective mitigation in clinical symptoms related to hypertension remain to be addressed. In the last decade, the research on traditional Chinese medicine(TCM) treatment of hypertension has received much attention and achieved remarkable progress. The TCM treatment of hypertension is the most active area of research with integrated Chinese and western medicine in China. In addition to lowering blood pressure smoothly, TCM can alleviate clinical symptoms, reverse risk factors, improve the quality of life, and protect target organs from the damage caused by hypertension. This article systematically reviews the research progress of TCM in treating hypertension in the last decade from the following four aspects: consensus on guideline, clinical trial, experimental study, and systematic review/Meta-analysis. It summarized the evidence of TCM in reducing blood pressure and clarified the mechanism of TCM in reducing blood pressure, aiming to provide a reference for the TCM diagnosis and treatment of hypertension and the development of new drugs.
    MeSH term(s) Humans ; Antihypertensive Agents/therapeutic use ; Drugs, Chinese Herbal/therapeutic use ; Hypertension/drug therapy ; Medicine, Chinese Traditional
    Chemical Substances Antihypertensive Agents ; Drugs, Chinese Herbal
    Language Chinese
    Publishing date 2024-01-11
    Publishing country China
    Document type English Abstract ; Journal Article ; Systematic Review
    ZDB-ID 1004649-5
    ISSN 1001-5302 ; 0254-0029
    ISSN 1001-5302 ; 0254-0029
    DOI 10.19540/j.cnki.cjcmm.20230904.501
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    Zs.A 3056: Show issues Location:
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  10. Article: [Interpretation and review of Clinical Practice Guidelines for Management of Hypertension in China (2020 edition) and exploration of traditional Chinese medicine for antihypertensive treatment].

    Wang, Xiao-Ya / Wang, Peng-Qian / Xiong, Xing-Jiang

    Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica

    2023  Volume 48, Issue 17, Page(s) 4819–4824

    Abstract: Hypertension is the most important risk factor for cardiovascular disease-related deaths among urban and rural residents, and it has become a significant global public health issue. In October 2022, the Clinical Practice Guidelines for the Management of ... ...

    Abstract Hypertension is the most important risk factor for cardiovascular disease-related deaths among urban and rural residents, and it has become a significant global public health issue. In October 2022, the Clinical Practice Guidelines for the Management of Hypertension in China(hereinafter referred to as the Practice Guidelines) were jointly released by the National Cardiovascular Center and other academic organizations. The Practice Guidelines sparked extensive discussions as they clearly lowered the diagnostic criteria for hypertension, raised the blood pressure targets for elderly patients, and proposed changes in the timing of early medication intervention. While these adjustments have some international evidence-based support, there is still debate regarding the cardiovascular benefits of intensified blood pressure control based on the existing level of evidence. Furthermore, whether the series of new standards proposed in the Practice Guidelines are suitable for the Chinese population and whether the hypertension control level in primary care in China can adapt to the new diagnostic and treatment standards require further in-depth research. In contrast to the strict blood pressure control concept emphasized in the Practice Guidelines, traditional Chinese medicine(TCM) emphasizes the concept of comprehensive prevention and treatment and holistic therapy in the treatment of hypertension, including prehypertension, hypertension, and target organ damage. In recent years, based on abundant clinical trial research and high-quality evidence-based support, the advantages of TCM in treating hypertension have gradually emerged. Previous studies by this research team have found that the pathogenesis of hypertension includes three major types: fire syndrome, fluid retention syndrome, and deficiency syndrome. TCM treatment of hypertension features stable blood pressure reduction, gentle blood pressure lowering, and long-lasting effects. In addition to blood pressure reduction, it also has effects such as reversing risk factors and protecting target organ damage. It demonstrates the characteristics of multiple targets, multiple components, and comprehensive regulation, and can be applied throughout the entire process of prevention and treatment, including prehypertension, hypertension, and target organ damage in the early, middle, and late stages of hypertension. Therefore, it has certain clinical application prospects.
    MeSH term(s) Aged ; Humans ; Antihypertensive Agents/therapeutic use ; China ; Hypertension/diagnosis ; Hypertension/drug therapy ; Medicine, Chinese Traditional ; Prehypertension/drug therapy ; Practice Guidelines as Topic
    Chemical Substances Antihypertensive Agents
    Language Chinese
    Publishing date 2023-10-05
    Publishing country China
    Document type English Abstract ; Journal Article
    ZDB-ID 1004649-5
    ISSN 1001-5302 ; 0254-0029
    ISSN 1001-5302 ; 0254-0029
    DOI 10.19540/j.cnki.cjcmm.20230603.501
    Database MEDical Literature Analysis and Retrieval System OnLINE

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