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"Yu, Ping"
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Triple product amplitude from chiral string
A
bstract
In this paper, we proposed a worldsheet construction of a subset of triple product amplitudes proposed by Huang and Remmen (2022). We start with closed bosonic strings but left and right-moving momenta are not necessarily equal. Instead, they satisfy certain conditions. We called them section conditions. These conditions are generalizations of the section condition in double field theory. The vertex operators of chiral strings have nontrivial monodromy, so we interpret them as attached to the end of defects. In the calculation of the amplitude, we not only have to integrate over the moduli space, we also have to sum over different defect configurations.
Unitarity and other consistency conditions for chiral string amplitudes are checked. We found the graviton amplitude, the Virasoro amplitude, and also a special kind of amplitude that has one infinite spin tower. Similar kinds of amplitude have appeared in bootstrap literature. The more general
N
-point amplitude could be obtained from a modified KLT relation. The five-point chiral string amplitude is also explicitly calculated.
Journal Article
The development of e-governance in China : improving cybersecurity and promoting informatization as means for modernizing state governance
This book figures out that network security and informatization have entered a development stage of greater permeation and deeper integration into all aspects of the economy and society. In particular since the 2008 financial crisis, the world's major economies have placed a strategic focus on network security and informatization in order to seek out new growth points, alleviate energy and ecological pressures, improve living standards, and improve social governance through new technological transformations in fields such as cloud computing, the Internet of Things, mobile internet, big data, smart cities, and a wave of applications. The effects on the economy and society have emerged and will continue to make significant progress. Based on China's stage of new urbanization, industrialization, informatization, and agricultural modernization and major characteristics, as well as the intrinsic need for synchronized development, this book encourages society to accelerate the pace of development, expand the scope of work and promote informatization and the comprehensive, coordinated, effective linking and deep integration of informatization with all areas of the economy and society.-- Provided by publisher.
BOOK
Mental Health and Psychosocial Problems of Medical Health Workers during the COVID-19 Epidemic in China
Objective: We explored whether medical health workers had more psychosocial problems than nonmedical health workers during the COVID-19 outbreak. Methods: An online survey was run from February 19 to March 6, 2020; a total of 2,182 Chinese subjects participated. Mental health variables were assessed via the Insomnia Severity Index (ISI), the Symptom Check List-revised (SCL-90-R), and the Patient Health Questionnaire-4 (PHQ-4), which included a 2-item anxiety scale and a 2-item depression scale (PHQ-2). Results: Compared with nonmedical health workers (n = 1,255), medical health workers (n = 927) had a higher prevalence of insomnia (38.4 vs. 30.5%, p < 0.01), anxiety (13.0 vs. 8.5%, p < 0.01), depression (12.2 vs. 9.5%; p< 0.04), somatization (1.6 vs. 0.4%; p < 0.01), and obsessive-compulsive symptoms (5.3 vs. 2.2%; p < 0.01). They also had higher total scores of ISI, GAD-2, PHQ-2, and SCL-90-R obsessive-compulsive symptoms (p ≤ 0.01). Among medical health workers, having organic disease was an independent factor for insomnia, anxiety, depression, somatization, and obsessive-compulsive symptoms (p < 0.05 or 0.01). Living in rural areas, being female, and being at risk of contact with COVID-19 patients were the most common risk factors for insomnia, anxiety, obsessive-compulsive symptoms, and depression (p < 0.01 or 0.05). Among nonmedical health workers, having organic disease was a risk factor for insomnia, depression, and obsessive-compulsive symptoms (p < 0.01 or 0.05). Conclusions: During the COVID-19 outbreak, medical health workers had psychosocial problems and risk factors for developing them. They were in need of attention and recovery programs.
Journal Article
أديان شينجيانغ
الكتاب ضمن سلسلة \"شينجيانغ الجميلة\" الصادرة عام 2015 عن بيت الحكمة، والتي تشرح كل ما يتعلق بمنطقة شينجيانغ، من حيث العادات والتقاليد، والثروات، والفنون، والتاريخ، والجغرافيا، ونمط الحياة فيها، والآكلات المشهورة بها، وأهميتها الدبلوماسية، وحتى الخلفية الدينية لها. وفي هذا الكتاب نفهم الأديان التي يؤمن بها أهل شينجيانغ وتاريخها وسياستها.
Book
Gut Microbiota-brain Axis
Objective: To systematically review the updated information about the gut microbiota-brain axis.
Data Sources: All articles about gut microbiota-brain axis published up to July 18, 2016, were identified through a literature search on PubMed, ScienceDirect, and Web of Science, with the keywords of \"gut microbiota\", \"gut-brain axis\", and \"neuroscience\".
Study Selection: All relevant articles on gut microbiota and gut-brain axis were included and carefully reviewed, with no limitation of study design.
Results: It is well-recognized that gut microbiota affects the brain's physiological, behavioral, and cognitive functions although its precise mechanism has not yet been fully understood. Gut microbiota-brain axis may include gut microbiota and their metabolic products, enteric nervous system, sympathetic and parasympathetic branches within the autonomic nervous system, neural-immune system, neuroendocrine system, and central nervous system. Moreover, there may be five communication routes between gut microbiota and brain, including the gut-brain's neural network, neuroendocrine-hypothalamic-pituitary-adrenal axis, gut immune system, some neurotransmitters and neural regulators synthesized by gut bacteria, and barrier paths including intestinal mucosal barrier and blood-brain barrier. The microbiome is used to define the composition and functional characteristics of gut microbiota, and metagenomics is an appropriate technique to characterize gut microbiota.
Conclusions: Gut microbiota-brain axis refers to a bidirectional information network between the gut microbiota and the brain, which may provide a new way to protect the brain in the near future.
Journal Article
Silk roads
In the ninth century CE, an Arabian ship sank off the coast of Indonesia. The objects found in the wreckage have provided extraordinary evidence of the nature, scale and diversity of trade between Tang China and the Islamic Abbasid dynasty, revealing the extent of a large-scale operation. This is just one example of the sprawling and extensive networks of contacts and exchanges across Afro-Eurasia, from Japan to Britain, in the period 500 to 1000 CE. This book challenges the concept of the 'Silk Roads' as a simple history of trade between East and West.
BOOK
Giant photothermal nonlinearity in a single silicon nanostructure
Silicon photonics have attracted significant interest because of their potential in integrated photonics components and all-dielectric meta-optics elements. One major challenge is to achieve active control via strong photon–photon interactions, i.e. optical nonlinearity, which is intrinsically weak in silicon. To boost the nonlinear response, practical applications rely on resonant structures such as microring resonators or photonic crystals. Nevertheless, their typical footprints are larger than 10 μm. Here, we show that 100 nm silicon nano-resonators exhibit a giant photothermal nonlinearity, yielding 90% reversible and repeatable modulation from linear scattering response at low excitation intensities. The equivalent nonlinear index is five-orders larger compared with bulk, based on Mie resonance enhanced absorption and high-efficiency heating in thermally isolated nanostructures. Furthermore, the nanoscale thermal relaxation time reaches nanosecond. This large and fast nonlinearity leads to potential applications for GHz all-optical control at the nanoscale and super-resolution imaging of silicon.
Resonant structures are a promising method to enhance the nonlinear response of Si, however they are typically larger than 10 μm. Here, the authors present Si nano-resonators that amplify photothermal nonlinearity, resulting in reversible and repeatable modulation.
Journal Article
Diplomacy of quasi-alliances in the Middle East
Quasi-alliance refers to the ideation, mechanism and behavior of policy-makers to carry out security cooperation through informal political and security arrangements. As a \"gray zone\" between alliance and neutrality, quasi-alliance is a hidden national security statecraft. Based on declassified archives and secondary sources, this book probes the theory and practice of quasi-alliances in the Middle East. Four cases are chosen to test the hypotheses of quasi-alliance, one of which is the Anglo-French-Israeli quasi-alliance during the Suez Canal War of 1956.
Book
Electrically-controlled digital metasurface device for light projection displays
Light projection displays play an increasingly important role in our modern life. Core projection systems including liquid crystal displays and digital micromirror devices can impose spatial light modulation and actively shape light waves. Recently, the advent of metasurfaces has revolutionized design concepts in nanophotonics, enabling a new family of optical elements with exceptional degrees of freedom. Here, we demonstrate a light projection display technology based on optical metasurfaces, called digital metasurface device (DMSD). Each metasurface pixel in a DMSD is electrically reconfigurable with well-controlled programmability and addressability. The DMSD can not only continuously modulate the intensity of light with high contrast, but also shape the wavefront of light generated by each metasurface pixel and dynamically switch between arbitrary holographic patterns. Our approach will pave an avenue towards the development of customized light projection devices. It will also drive the field of dynamic optical metasurfaces with fresh momentum and inspiring concepts.
Controllable and low-cost holographic display devices are always desired. Here the authors demonstrate an approach of creating light projection device based on electrical control of digital metasurface device.
Journal Article