276 research outputs found
PEDF in Diabetic Retinopathy: A Protective Effect of Oxidative Stress
Diabetic retinopathy (DR) is a major cause of blindness in working age adults, and oxidative stress plays a vital role in the pathogenesis of DR. Pigment-epithelium-derived factor (PEDF), a multifunctional protein, has shown to inhibit the development of DR by accumulating evidence. This paper highlights the current understanding of probable mechanism about how PEDF blocks the deterioration of DR through its antioxidative properties and application prospects of PEDF as a novel therapeutic target in DR. Gene therapy of PEDF is becoming more and more acceptable and will widely be applied to the actual treatment in the near future
Orbital density wave induced by electron-lattice coupling in orthorhombic iron pnictides
In this paper we explore the magnetic and orbital properties closely related
to a tetragonal-orthorhombic structural phase transition in iron pnictides
based on both two- and five-orbital Hubbard models. The electron-lattice
coupling, which interplays with electronic interaction, is self-consistently
treated. Our results reveal that the orbital polarization stabilizes the spin
density wave (SDW) order in both tetragonal and orthorhombic phases. However,
the ferro-orbital density wave (F-ODW) only occurs in the orthorhombic phase
rather than in the tetragonal one. Magnetic moments of Fe are small in the
intermediate Coulomb interaction region for the striped antiferromangnetic
phase in the realistic five orbital model. The anisotropic Fermi surface in the
SDW/ODW orthorhombic phase is well in agreement with the recent angle-resolved
photoemission spectroscopy experiments. These results suggest a scenario that
the magnetic phase transition is driven by the ODW order mainly arising from
the electron-lattice coupling.Comment: 21 pages, 10 figure
Seasonal variation in systemic lupus erythematosus and rheumatoid arthritis: an ecological study In based on internet searches
Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease in which immune regulation is disrupted and characterized by intense inflammation and damage to multiple organs or systems. Rheumatoid arthritis (RA) is another systemic autoimmune disease characterized by chronic synovial joint inflammation that leads to disability and poor quality of life. Although the etiologies and pathogenesis of SLE and RA are not fully understood, it is generally accepted that they are both caused by interactions between genetic and environmental factors. In recent years, emerging studies have demonstrated the potential role of seasonality in the development and disease activity of variety of autoimmune diseases [[1], [2], [3]]
Beimingwu: A Learnware Dock System
The learnware paradigm proposed by Zhou [2016] aims to enable users to reuse
numerous existing well-trained models instead of building machine learning
models from scratch, with the hope of solving new user tasks even beyond
models' original purposes. In this paradigm, developers worldwide can submit
their high-performing models spontaneously to the learnware dock system
(formerly known as learnware market) without revealing their training data.
Once the dock system accepts the model, it assigns a specification and
accommodates the model. This specification allows the model to be adequately
identified and assembled to reuse according to future users' needs, even if
they have no prior knowledge of the model. This paradigm greatly differs from
the current big model direction and it is expected that a learnware dock system
housing millions or more high-performing models could offer excellent
capabilities for both planned tasks where big models are applicable; and
unplanned, specialized, data-sensitive scenarios where big models are not
present or applicable.
This paper describes Beimingwu, the first open-source learnware dock system
providing foundational support for future research of learnware paradigm.The
system significantly streamlines the model development for new user tasks,
thanks to its integrated architecture and engine design, extensive engineering
implementations and optimizations, and the integration of various algorithms
for learnware identification and reuse. Notably, this is possible even for
users with limited data and minimal expertise in machine learning, without
compromising the raw data's security. Beimingwu supports the entire process of
learnware paradigm. The system lays the foundation for future research in
learnware-related algorithms and systems, and prepares the ground for hosting a
vast array of learnwares and establishing a learnware ecosystem
Changes and related factors of blood CCN1 levels in diabetic patients
ObjectiveTo study the differences in blood cellular communication network factor 1 (CCN1) levels between patients with diabetes mellitus (DM) and healthy individuals and to explore the relationship between CCN1 and diabetic retinopathy (DR).MethodsPlasma CCN1 levels were detected using ELISA in 50 healthy controls, 74 patients with diabetes without diabetic retinopathy (DM group), and 69 patients with diabetic retinopathy (DR group). Correlations between CCN1 levels and age, body mass index, mean arterial pressure, hemoglobin A1c, and other factors were analyzed. The relationship between CCN1 expression and DR was explored using logistic regression after adjusting for confounding factors. Blood mRNA sequencing analysis was performed for all subjects, and the molecular changes that may be related to CCN1 were explored. The retinal vasculature of streptozotocin-induced diabetic rats was examined using fundus fluorescein angiography; in addition, retinal protein expression was examined using western blotting.ResultsPlasma CCN1 levels in patients with DR were significantly higher than in the control and DM groups; however, no significant differences were observed between healthy controls and patients with DM. CCN1 levels negatively correlated with body mass index and positively correlated with the duration of diabetes and urea levels. It was observed that high (OR 4.72, 95% CI: 1.10–20.25) and very high (OR 8.54, 95% CI: 2.00–36.51) levels of CCN1 were risk factors for DR. Blood mRNA sequencing analysis revealed that CCN1-related pathways were significantly altered in the DR group. The expression of hypoxia-, oxidative stress-, and dephosphorylation-related proteins were elevated, while that of tight junction proteins were reduced in the retinas of diabetic rats.ConclusionBlood CCN1 levels are significantly elevated in patients with DR. High and very high levels of plasma CCN1 are risk factors for DR. Blood CCN1 level may be a potential biomarker for diagnosis of DR. The effects of CCN1 on DR may be related to hypoxia, oxidative stress, and dephosphorylation
Strongly-coupled nanotube electromechanical resonators
Coupling an electromechanical resonator with carbon-nanotube quantum dots is
a significant method to control both the electronic charge and the spin quantum
states. By exploiting a novel micro-transfer technique, we fabricate two
strongly-coupled and electrically-tunable mechanical resonators on a single
carbon nanotube for the first time. The frequency of the two resonators can be
individually tuned by the bottom gates, and strong coupling is observed between
the electron charge and phonon modes of each resonator. Furthermore, the
conductance of either resonator can be nonlocally modulated by the phonon modes
in the other resonator. Strong coupling is observed between the phonon modes of
the two resonators, which provides an effective long distance electron-electron
interaction. The generation of phonon-mediated-spin entanglement is also
theoretically analyzed for the two resonators. This strongly-coupled nanotube
electromechanical resonator array provides an experimental platform for future
studies of the coherent electron-phonon interaction, the phonon mediated
long-distance electron interaction, and entanglement state generation
Revisiting the quantum Szilard engine with fully quantum considerations
By considering level shifting during the insertion process we revisit the
quantum Szilard engine (QSZE) with fully quantum consideration. We derive the
general expressions of the heat absorbed from thermal bath and the total work
done to the environment by the system in a cycle with two different cyclic
strategies. We find that only the quantum information contributes to the
absorbed heat, and the classical information acts like a feedback controller
and has no direct effect on the absorbed heat. This is the first demonstration
of the different effects of quantum information and classical information for
extracting heat from the bath in the QSZE. Moreover, when the well width
or the temperature of the bath
the QSZE reduces to the classical Szilard engine (CSZE), and the total work
satisfies the relation as obtained by
Sang Wook Kim et al. [Phys. Rev. Lett. 106, 070401 (2011)] for one particle
case.Comment: 17 pages, 3 figures, to be published in Annals of Physics(NY
Synthetic five-wave mixing in an integrated microcavity for visible-telecom entanglement generation
Nonlinear optics processes lie at the heart of photonics and quantum optics
for their indispensable role in light sources and information processing.
During the past decades, the three- and four-wave mixing ( and
) effects have been extensively studied, especially in the
micro-/nano-structures by which the photon-photon interaction strength is
greatly enhanced. So far, the high-order nonlinearity beyond the
has rarely been studied in dielectric materials due to their weak intrinsic
nonlinear susceptibility, even in high-quality microcavities. Here, an
effective five-wave mixing process () is synthesized for the first
time, by incorporating and processes in a single
microcavity. The coherence of the synthetic is verified by
generating time-energy entangled visible-telecom photon-pairs, which requires
only one drive laser at the telecom waveband. The photon pair generation rate
from the synthetic process shows an enhancement factor over times upon
intrinsic five-wave mixing. Our work demonstrates a universal approach of
nonlinear synthesis via photonic structure engineering at the mesoscopic scale
rather than material engineering, and thus opens a new avenue for realizing
high-order optical nonlinearities and exploring novel functional photonic
devices.Comment: 4 figure
Photopic pupil size change in myopic orthokeratology and its influence on axial length elongation
AIM: To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology (ortho-k) over 1-year period and its effects on the axial elongation. METHODS: A total of 202 Chinese myopic children were enrolled in this prospective clinical trial. Ninety-five subjects in ortho-k group and eighty-eight subjects in spectacle group completed the 1-year study. Axial length (AL) was measured before enrollment and every 6mo after the start of ortho-k. The photopic pupil diameter (PPD) was determined using the Pentacam AXL and measured in an examination room with lighting of 300-310 Lx. Stepwise multiple linear regression analysis was used to identify variables contribution to axial elongation. RESULTS: Compared with spectacle group, the average 1-year axial elongation was significantly slower in the ortho-k group (0.25±0.27 vs 0.44±0.23 mm, P0.05, Bonferroni correction). The 4.81 mm PPD may be a possible cutoff point in the ortho-k group. Subjects with PPD below or equal to 4.81 mm tended to have smaller axial elongation compared to subjects with PPD above 4.81 mm after 1-year period (t=-3.09, P=0.003). In ortho-k group, univariate analyses indicated that those with older age, greater degree of myopia, longer AL, smaller baseline PPD (PPDbaseline) experienced a smaller change in AL. In multivariate analyses, older age, greater AL and smaller PPDbaseline were associated with smaller increases in AL. In spectacle group, PPD tended to be stable (P>0.05, Bonferroni correction) and did not affect axial growth. CONCLUSION: PPDs experience significantly decreases at 1-month and 3-month ortho-k treatment. Children with smaller PPD tend to experience slower axial elongation and may benefit more from ortho-k
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