5,822 research outputs found
Non-commutative Geometry Modified Non-Gaussianities of Cosmological Perturbation
We investigate the noncommutative effect on the non-Gaussianities of
primordial cosmological perturbation. In the lowest order of string length and
slow-roll parameter, we find that in the models with small speed of sound the
noncommutative modifications could be observable if assuming a relatively low
string scale. In particular, the dominant modification of non-Gaussianity
estimator f_{NL} could reach O(1) in DBI inflation and K-inflation. The
corrections are sensitive to the speed of sound and the choice of string length
scale. Moreover the shapes of the corrected non-Gaussianities are distinct from
that of ordinary ones.Comment: 26 pages, 3 figures Added references, changed conten
Clinical observation of treatment of fungal corneal ulcer with application of iodine tincture and fluconazole
AIM: To explore the effect of 30g/L iodine rubbed and debridement of wound together with 2g/L fluconazole in the treatment of fungal corneal ulcers. <p>METHODS: Fifty fungal keratitis cases(50 eyes)diagnosed by corneal smear examination were cleaned locally, iodine blanch. All patients were given 2g/L fluconazole for systemic treatment, treated eye with 2g/L fluconazole eye-drops and loxacin eye-drops, and 30g/L atropine eye ointment dilate the pupils.<p>RESULTS:Fifty cases(50 eyes)were selected, of which, 40 cases were healed, 8 cases were improved and 2 cases were aggravated with operation being given.<p>CONCLUSION:After early and timely diagnosis of fungal keratitis, local debridement, 30g/L iodine rubbed the wound and joint with systemic and local treatment of fluconazole can achieve good effect
The protective effect of resveratrol on human lens epithelial cells against ultraviolet-induced apoptosis
AIM: To investigate the protective effect of resveratrol on human lens epithelial cells against ultraviolet-induced apoptosis. METHODS:Subcultured human lens epithelial cell line, ultraviolet induced cell apoptosis, 20μmol/L resveratrol pretreated cell, the indicators change was observed: rate of apoptosis was detected by flow cytometry and apoptosis-related factors of caspses-3 and caspase-9 were detected by colorimetric detection, ultrastructure changes were observed under transmission electron microscope. RESULTS: Flow cytometry instrument testing found that resveratrol can suppress the apoptosis induced by ultraviolet irradiation, caspses-3 and caspase-9 content in positive control group were significantly higher than that of the negative control group at the same time period, the difference was statistically significant(P<0.05); caspses-3 and caspase-9 content in experimental group were lower than that in the positive control group at the same time, the difference was statistically significant(P<0.05). In addition, the damage of human lens epithelial cells was alleviated with the incubation time of resveratrol elongated. CONCLUSION:Resveratrol may inhibit ultraviolet-induced apoptosis of human lens epithelial cells, it has preventive function against radioactive cataract, and it can provide reliable evidence for pursuing effective medicine to prevent and treat cataract
Tumor-derived VEGF modulates hematopoiesis
VEGF-induced angiogenesis significantly contributes to tumor growth, invasion and metastasis. However, little is known about its hematopoietic activity during malignant development and progression. Here we show that in a mouse tumor model, tumor-derived VEGF acts as an endocrine-like hormone to induce extramedullary hematopoiesis by targeting distal organs in the host. In tumor-bearing mice, circulating VEGF induced hepatomegaly and splenomegaly owing to vessel dilation, tortuosity and activation of hematopoiesis. Furthermore, VEGFR1 and VEGFR2 were primarily localized in blood vessels rather than hepatocytes or splenocytes, demonstrating that alteration of angiogenic profiles modulates hematopoiesis in these organs. Stimulation of extramedullary hematopoiesis sheds new light on complex biological functions of VEGF and significantly increases our understanding of molecular mechanisms underlying VEGF-induced tumor growth
Heterogeneous Trajectory Forecasting via Risk and Scene Graph Learning
Heterogeneous trajectory forecasting is critical for intelligent
transportation systems, while it is challenging because of the difficulty for
modeling the complex interaction relations among the heterogeneous road agents
as well as their agent-environment constraint. In this work, we propose a risk
and scene graph learning method for trajectory forecasting of heterogeneous
road agents, which consists of a Heterogeneous Risk Graph (HRG) and a
Hierarchical Scene Graph (HSG) from the aspects of agent category and their
movable semantic regions. HRG groups each kind of road agents and calculates
their interaction adjacency matrix based on an effective collision risk metric.
HSG of driving scene is modeled by inferring the relationship between road
agents and road semantic layout aligned by the road scene grammar. Based on
this formulation, we can obtain an effective trajectory forecasting in driving
situations, and superior performance to other state-of-the-art approaches is
demonstrated by exhaustive experiments on the nuScenes, ApolloScape, and
Argoverse datasets.Comment: Submitted to IEEE Transactions on Intelligent Transportation Systems,
202
Observation of the chiral anomaly induced negative magneto-resistance in 3D Weyl semi-metal TaAs
Weyl semi-metal is the three dimensional analog of graphene. According to the
quantum field theory, the appearance of Weyl points near the Fermi level will
cause novel transport phenomena related to chiral anomaly. In the present
paper, we report the first experimental evidence for the long-anticipated
negative magneto-resistance generated by the chiral anomaly in a newly
predicted time-reversal invariant Weyl semi-metal material TaAs. Clear
Shubnikov de Haas oscillations (SdH) have been detected starting from very weak
magnetic field. Analysis of the SdH peaks gives the Berry phase accumulated
along the cyclotron orbits to be {\pi}, indicating the existence of Weyl
points.Comment: Submitted in February'1
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