190 research outputs found
Continuous and Distribution-free Probabilistic Wind Power Forecasting: A Conditional Normalizing Flow Approach
We present a data-driven approach for probabilistic wind power forecasting
based on conditional normalizing flow (CNF). In contrast with the existing,
this approach is distribution-free (as for non-parametric and quantile-based
approaches) and can directly yield continuous probability densities, hence
avoiding quantile crossing. It relies on a base distribution and a set of
bijective mappings. Both the shape parameters of the base distribution and the
bijective mappings are approximated with neural networks. Spline-based
conditional normalizing flow is considered owing to its non-affine
characteristics. Over the training phase, the model sequentially maps input
examples onto samples of base distribution, given the conditional contexts,
where parameters are estimated through maximum likelihood. To issue
probabilistic forecasts, one eventually maps samples of the base distribution
into samples of a desired distribution. Case studies based on open datasets
validate the effectiveness of the proposed model, and allows us to discuss its
advantages and caveats with respect to the state of the art.Comment: The second revision to IEEE Transactions on Sustainable Energ
Gravity anomalies and lithospheric flexure around the Longmen Shan deduced from combinations of in situ observations and EGM2008 data
Ponatinib efficiently kills imatinib-resistant chronic eosinophilic leukemia cells harboring gatekeeper mutant T674I FIP1L1-PDGFRα: roles of Mcl-1 and β-catenin
Electrospun chitosan-graft-poly (É›-caprolactone)/poly (É›-caprolactone) nanofibrous scaffolds for retinal tissue engineering
A promising therapy for retinal diseases is to employ biodegradable scaffolds to deliver retinal progenitor cells (RPCs) for repairing damaged or diseased retinal tissue. In the present study, cationic chitosan-graft-poly(ɛ-caprolactone)/polycaprolactone (CS-PCL/PCL) hybrid scaffolds were successfully prepared by electrospinning. Characterization of the obtained nanofibrous scaffolds indicated that zeta-potential, fiber diameter, and the content of amino groups on their surface were closely correlated with the amount of CS-PCL in CS-PCL/PCL scaffolds. To assess the cell–scaffold interaction, mice RPCs (mRPCs) were cultured on the electrospun scaffolds for 7 days. In-vitro proliferation assays revealed that mRPCs proliferated faster on the CS-PCL/PCL (20/80) scaffolds than the other electrospun scaffolds. Scanning electron microscopy and the real-time quantitative polymerase chain reaction results showed that mRPCs grown on CS-PCL/PCL (20/80) scaffolds were more likely to differentiate towards retinal neurons than those on PCL scaffolds. Taken together, these results suggest that CS-PCL/PCL(20/80) scaffolds have potential application in retinal tissue engineering
Porphysome nanovesicles generated by porphyrin bilayers for use as multimodal biophotonic contrast agents
Optically active nanomaterials promise to advance a range of biophotonic techniques through nanoscale optical effects and integration of multiple imaging and therapeutic modalities. Here, we report the development of porphysomes; nanovesicles formed from self-assembled porphyrin bilayers that generated large, tunable extinction coefficients, structure-dependent fluorescence self-quenching and unique photothermal and photoacoustic properties. Porphysomes enabled the sensitive visualization of lymphatic systems using photoacoustic tomography. Near-infrared fluorescence generation could be restored on dissociation, creating opportunities for low-background fluorescence imaging. As a result of their organic nature, porphysomes were enzymatically biodegradable and induced minimal acute toxicity in mice with intravenous doses of 1,000 mg kg^(−1). In a similar manner to liposomes, the large aqueous core of porphysomes could be passively or actively loaded. Following systemic administration, porphysomes accumulated in tumours of xenograft-bearing mice and laser irradiation induced photothermal tumour ablation. The optical properties and biocompatibility of porphysomes demonstrate the multimodal potential of organic nanoparticles for biophotonic imaging and therapy
KillerRed protein based in vivo photodynamic therapy and corresponding tumor metabolic imaging
Photodynamic therapy (PDT) gains wide attention as a useful therapeutic method for cancer. It is mediated by the oxygen and photosensitizer under the specific light irradiation to produce the reactive oxygen species (ROS), which induce cellular toxicity and regulate the redox potential in tumor cells. Nowadays, genetic photosensitizers of low toxicity and easy production are required to be developed. KillerRed, a unique red fluorescent protein exhibiting excellent phototoxic properties, has the potential to act as a photosensitizer in the application of tumor PDT. Meantime, the course of tumor redox metabolism during this treatment was rarely investigated so far. Thus here, we investigated the effects of KillerRed-based PDT on tumor growth in vivo and examined the subsequent tumor metabolic states including the changes of nicotinamide adenine dinucleotide hydrogen (NADH) and flavoprotein (Fp), two important metabolic coenzymes of tumor cells. Results showed the tumor growth had been significantly inhibited by KillerRed-based PDT treatment compared to control groups. A home-made cryo-imaging redox scanner was used to measure intrinsic fluorescence and exogenous KillerRed fluorescence signals in tumors. The Fp signal was elevated by nearly 4.5-fold, while the NADH signal decreased by 66% after light irradiation, indicating that Fp and NADH were oxidized in the course of KillerRed-based PDT. Furthermore, we also observed correlation between the fluorescence distribution of KillerRed and NADH. It suggests that the KillerRed protein based PDT might provide a new approach for tumor therapy accompanied by altering tumor metabolism
Multi-sensor Image Data Fusion based on Pixel-Level Weights of Wavelet and the PCA Transform
Abstract -The goal of image fusion is to create new images that are more suitable for the purposes of human visual perception, object detection and target recognition. For Automatic Target Recognition (ATR), we can use multi-sensor data including visible and infrared images to increase the recognition rate. In this paper, we propose a new multiresolution data fusion scheme based on the principal component analysis (PCA) transform and the pixel-level weights wavelet transform including thermal weights and visual weights. In order to get a more ideal fusion result, a linear local mapping which based on the PCA is used to create a new "origin" image of the image fusion. We use multiresolution decompositions to represent the input images at different scales, present a multiresolution/ multimodal segmentation to partition the image domain at these scales. The crucial idea is to use this segmentation to guide the fusion process. Physical thermal weights and perceptive visual weights are used as segmentation multimodals. Daubechies Wavelet is choosen as the Wavelet Basis. Experimental results confirm that the proposed algorithm is the best image sharpening method and can best maintain the spectral information of the original infrared image. Also, the proposed technique performs better than the other ones in the literature, more robust and effective, from both subjective visual effects and objective statistical analysis results
The roles of inflammasomes in cancer
Inflammation is a key characteristic of all stages of tumor development, including tumor initiation, progression, malignant transformation, invasion, and metastasis. Inflammasomes are an important component of the inflammatory response and an indispensable part of the innate immune system. Inflammasomes regulate the nature of infiltrating immune cells by signaling the secretion of different cytokines and chemokines, thus regulating the anti-tumor immunity of the body. Inflammasome expression patterns vary across different tumor types and stages, playing different roles during tumor progression. The complex diversity of the inflammasomes is determined by both internal and external factors relating to tumor establishment and progression. Therefore, elucidating the specific effects of different inflammasomes in anti-tumor immunity is critical for promoting the discovery of inflammasome-targeting drugs. This review focuses on the structure, activation pathway, and identification methods of the NLRP3, NLRC4, NLRP1 and AIM2 inflammasomes. Herein, we also explore the role of inflammasomes in different cancers and their complex regulatory mechanisms, and discuss current and future directions for targeting inflammasomes in cancer therapy. A detailed knowledge of inflammasome function and regulation may lead to novel therapies that target the activation of inflammasomes as well as the discovery of new drug targets
Phases and magnetism at the microscale in compounds containing nominal Pb10-xCux(PO4)6O
Achieving superconductivity at room temperature could lead to substantial
advancements in industry and technology. Recently, a compound known as Cu-doped
lead-apatite, Pb10-xCux(PO4)6O (0.9 < x < 1.1), referred to as "LK-99", has
been reported to exhibit unusual electrical and magnetic behaviors that appear
to resemble a superconducting transition above room temperature. In this work
we collected multiphase samples containing the nominal Pb10-xCux(PO4)6O phase
(no superconductivity observed in our measured samples), synthesized by three
independent groups, and studied their chemical, magnetic, and electrical
properties at the microscale to overcome difficulties in bulk measurements.
Through the utilization of optical, scanning electron, atomic force, and
scanning diamond nitrogen-vacancy microscopy techniques, we are able to
establish a link between local magnetic properties and specific microscale
chemical phases. Our findings indicate that while the Pb10-xCux(PO4)6O phase
seems to have a mixed magnetism contribution, a significant fraction of the
diamagnetic response can be attributed to Cu-rich regions (e.g., Cu2S derived
from a reagent used in the synthesis). Additionally, our electrical
measurements reveal the phenomenon of current path switch and a change in
resistance states of Cu2S. This provides a potential explanation for the
electrical behavior observed in compounds related to Pb10-xCux(PO4)6O.Comment: 14 pages, 5 figures; Physical Review Material
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