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Guided image filtering (GIF) based cost aggregation or disparity refinement stereo matching algorithms are studied extensively owing to the edge-aware preserved smoothing property. However, GIF suffers from halo artifacts in sharp edges and shows high computational costs on high-resolution images. The performance of GIF in stereo matching would be limited by the above two defects. To solve these problems, a novel fast gradient domain guided image filtering (F-GDGIF) is proposed. To be specific, halo artifacts are effectively alleviated by incorporating an efficient multi-scale edge-aware weighting into GIF. With this multi-scale weighting, edges can be preserved much better. In addition, high computational costs are cut down by sub-sampling strategy, which decreases the computational complexity from O (N) to O (N/s 2) (s : sub-sampling ratio) To verify the effectiveness of the algorithm, F-GDGIF is applied to cost aggregation and disparity refinement in stereo matching algorithms respectively. Experiments on the Middlebury evaluation benchmark demonstrate that F-GDGIF based stereo matching method can generate more accuracy disparity maps with low computational cost compared to other GIF based methods. • By incorporating a multi-scale edge-aware weighting and sub-sampling strategy into GIF, a novel fast gradient domain guided image filter (F-GDGIF) is proposed, which achieves better edge-aware performance with a faster execution time. • The proposed F-GDGIF is employed in cost aggregation. Due to its advantages of edge preserved smoothing property and low computational complexity, F-GDGIF based cost aggregation method achieves better performance compared to other GIF based methods. • Apart from cost aggregation, F-GDGIF is also adopted in disparity refinement and achieved better results compared to GIF based method. [ABSTRACT FROM AUTHOR]

We report the serendipitous discovery of several ULX candidates in XMM-Newton observations. Such discoveries suggest that ULXs are not a negligible component of the extragalactic X-ray source population. [ABSTRACT FROM PUBLISHER]

As a space X-ray imaging mission dedicated to time-domain astrophysics, the Einstein Probe (EP) carries two kinds of scientific payloads, the wide-field X-ray telescope (WXT) and the follow-up X-ray telescope (FXT). FXT utilizes Wolter-I type mirrors and the pn-CCD detectors. In this work, we investigate the in-orbit background of FXT based on Geant4 simulation. The impact of various space components present in the EP orbital environment are considered, such as the cosmic photon background, cosmic ray primary and secondary particles (e.g. protons, electrons and positrons), albedo gamma rays, and the low-energy protons near the geomagnetic equator. The obtained instrumental background at 0.5–10 keV, which is mainly induced by cosmic ray protons and cosmic photon background, corresponds to a level of ∼ 3. 1 × 10−2 counts s−1 keV−1 in the imaging area of the focal plane detector (FPD), i.e. 3.7 × 10−3 counts s−1 keV−1 cm−2 after normalization. Compared with the instrumental background, the field of view (FOV) background, which is induced by cosmic photons reflected by the optical mirror, dominates below 2 keV. Based on the simulated background level within the focal spot (a 30 ′ ′ -radius circle), the sensitivity of FXT is calculated, which could theoretically achieve several μ crab (in the order of 10−14 erg cm−2 s−1) in 0.5–2 keV and several tens of μ crab (in the order of 10−13 erg cm−2 s−1) in 2–10 keV for a pointed observation with an exposure of 25 min. This sensitivity becomes worse by a factor of ∼ 2 if additional 10% systematic uncertainty of the background subtraction is included. [ABSTRACT FROM AUTHOR]

Micro pore optical (MPO) device is a novel X-ray optical component with a unique 4 π solid-angle focusing capability and large effective area for specified weight ratio, which meet the requirements of the applications in modern X-ray astronomy. The focusing performance of flat MPO is a key factor affecting the detection capability of the finished device used for Lobster eye X-ray telescope. In this paper, to study the optical properties of the flat plate, we performed both numerical simulation and experimental measurements. The measured focal distance was 3650 mm ± 10 mm. The full width at half maximum of the measured focal spot in the vertical and horizontal direction was 1.83 mm and 3.27 mm, respectively. And the corresponding angular resolution was 1.73 arcmins and 3.08 arcmins. The simulation results showed that these two kinds of channel errors have a great influence on the point spread function of this device, which was in good agreement with the test results. • A set of point-to-point vacuum X-ray beam experimental set-up with a microfocus X-ray source was established. • The angular resolution in the vertical and horizontal direction was 1.73 arcmins and 3.08 arcmins. • By carrying out experiment, the rationality and correctness of this numerical model are confirmed. [ABSTRACT FROM AUTHOR]

Members of the leucine rich repeat (LRR) and PDZ domain (LAP) protein family are essential for animal development and histogenesis. Densin-180, encoded by LRRC7, is the only LAP protein selectively expressed in neurons. Densin-180 is a postsynaptic scaffold at glutamatergic synapses, linking cytoskeletal elements with signalling proteins such as the α-subunit of Ca 2+ /calmodulin-dependent protein kinase II. We have previously observed an association between high impact variants in LRRC7 and Intellectual Disability; also three individual cases with variants in LRRC7 had been described. We identify here 33 individuals (one of them previously described) with a dominant neurodevelopmental disorder due to heterozygous missense or loss-of-function variants in LRRC7. The clinical spectrum involves intellectual disability, autism, ADHD, aggression and, in several cases, hyperphagia-associated obesity. A PDZ domain variant interferes with synaptic targeting of Densin-180 in primary cultured neurons. Using in vitro systems (two hybrid, BioID, coimmunoprecipitation of tagged proteins from 293T cells) we identified new candidate interaction partners for the LRR domain, including protein phosphatase 1 (PP1), and observed that variants in the LRR reduced binding to these proteins. We conclude that LRRC7 encodes a major determinant of intellectual development and behaviour., (© 2024. The Author(s).)

Purpose: To establish a radiomics nomogram based on MRI radiomics features combined with clinical characteristics for distinguishing pleomorphic adenoma (PA) from warthin tumor (WT)., Methods: 294 patients with PA (n = 159) and WT (n = 135) confirmed by histopathology were included in this study between July 2017 and June 2023. Clinical factors including clinical data and MRI features were analyzed to establish clinical model. 10 MRI radiomics features were extracted and selected from T1WI and FS-T2WI, used to establish radiomics model and calculate radiomics scores (Rad-scores). Clinical factors and Rad-scores were combined to serve as crucial parameters for combined model. Through Receiver operator characteristics (ROC) curve and decision curve analysis (DCA), the discriminative values of the three models were qualified and compared, the best-performing combined model was visualized in the form of a radiomics nomogram., Results: The combined model demonstrated excellent discriminative performance for PA and WT in the training set (AUC=0.998) and testing set (AUC=0.993) and performed better compared with the clinical model and radiomics model in the training set (AUC=0.996, 0.952) and testing model (AUC=0.954, 0.849). The DCA showed that the combined model provided more overall clinical usefulness in distinguishing parotid PA from WT than another two models., Conclusion: An analytical radiomics nomogram based on MRI radiomics features, incorporating clinical factors, can effectively distinguish between PA and WT., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Objective: The pine wood nematode, Bursaphlenchus xylophilus, morphologically similar to B. mucronatus, is the pathogen of pine wilt disease. This study was focused on the endophytic bacteria present in these nematodes., Methods: Detailed observations were made on sections of all parts of the two types of nematodes by transmission electron microscope. The nematodes were surface-sterilized by soaking in 1% mercuric chloride and antibiotic mixture, and then ground and cultured on nutrient agar plate. The physiological and biochemical characteristics combined with molecular characterization of bacteria were analyzed and identified., Results: Endophytic bacteria were found in intestines of the two nematodes by transmission electron microscope observations. On the basis of surface sterilization, total three bacteria strains were obtained from B. xylophilus and B. mucronatus. These bacteria belong to Stenotrophomonas and Ewingella., Conclusion: It confirms the presence of endophytic bacteria in Bursaphelenchus xylophilus and B. mucronatus and these bacteria may play a physical and ecological roles in nematodes.