Exposure correction is one of the fundamental tasks in image processing and computational photography. While various methods have been proposed, they either fail to produce visually pleasing results, ...or only work well for limited types of image (e.g., underexposed images). In this paper, we present a novel automatic exposure correction method, which is able to robustly produce high‐quality results for images of various exposure conditions (e.g., underexposed, overexposed, and partially under‐ and over‐exposed). At the core of our approach is the proposed dual illumination estimation, where we separately cast the under‐and over‐exposure correction as trivial illumination estimation of the input image and the inverted input image. By performing dual illumination estimation, we obtain two intermediate exposure correction results for the input image, with one fixes the underexposed regions and the other one restores the overexposed regions. A multi‐exposure image fusion technique is then employed to adaptively blend the visually best exposed parts in the two intermediate exposure correction images and the input image into a globally well‐exposed image. Experiments on a number of challenging images demonstrate the effectiveness of the proposed approach and its superiority over the state‐of‐the‐art methods and popular automatic exposure correction tools.
Objective
To assess the accuracy of dynamic computer‐assisted implant surgery.
Materials and methods
An electronic search up to March 2020 was conducted using PubMed, Embase, and the Cochrane Central ...Register of Controlled Trial to identify studies using dynamic navigation in implant surgery, and additional manual search was performed as well. Clinical trials and model studies were selected. The primary outcome was accuracy. A single‐arm meta‐analysis of continuous data was conducted. Meta‐regression was utilized for comparison on study design, guidance method, jaw, and systems.
Results
Ten studies, four randomized controlled trials (RCT) and six prospective studies, met the inclusion criteria. A total of 1,298 drillings and implants were evaluated. The meta‐analysis of the accuracy (five clinical trials and five model studies) revealed average global platform deviation, global apex deviation, and angular deviation were 1.02 mm, 95% CI (0.83, 1.21), 1.33 mm, 95% CI (0.98, 1.67), and 3.59°, 95% CI (2.09, 5.09). Meta‐regression shown no difference between model studies and clinical trials (p = .295, 0.336, 0.185), drilling holes and implant (p = .36, 0.279, 0.695), maxilla and mandible (p = .875, 0.632, 0.281), and five different systems (p = .762, 0.342, 0.336).
Conclusion
Accuracy of dynamic computer‐aided implant surgery reaches a clinically acceptable range and has potential in clinical usage, but more patient‐centered outcomes and socio‐economic benefits should be reported.
White matter hyperintensities (WMH) are commonly found in the brains of healthy elderly individuals and have been associated with various neurological and geriatric disorders. In this paper, we ...present a study using deep fully convolutional network and ensemble models to automatically detect such WMH using fluid attenuation inversion recovery (FLAIR) and T1 magnetic resonance (MR) scans. The algorithm was evaluated and ranked 1st in the WMH Segmentation Challenge at MICCAI 2017. In the evaluation stage, the implementation of the algorithm was submitted to the challenge organizers, who then independently tested it on a hidden set of 110 cases from 5 scanners. Averaged dice score, precision and robust Hausdorff distance obtained on held-out test datasets were 80%, 84% and 6.30 mm respectively. These were the highest achieved in the challenge, suggesting the proposed method is the state-of-the-art. Detailed descriptions and quantitative analysis on key components of the system were provided. Furthermore, a study of cross-scanner evaluation is presented to discuss how the combination of modalities affect the generalization capability of the system. The adaptability of the system to different scanners and protocols is also investigated. A quantitative study is further presented to show the effect of ensemble size and the effectiveness of the ensemble model. Additionally, software and models of our method are made publicly available. The effectiveness and generalization capability of the proposed system show its potential for real-world clinical practice.
•Describe the design, methodology, implementation details of our winning method for WMH Segmentation Challenge at MICCAI 2017.•Present an evaluation on both the public training set and the held-out test sets, and compare to other participating methods.•Present a cross-scanner evaluation on the generalization capability of the system.•Present a quantitative and a statistical study on ensemble models to test the effect of ensemble size and each element.
Dielectric superstrates have been commonly utilized in tightly coupled dipole arrays (TCDAs) to help achieve better impedance matching over wide bandwidth and large scan volume. However, the ...dielectric slabs inevitably increase the total weight and fabrication complexity for TCDAs. Thus, an investigation of a new TCDA element excluding additional dielectric superstrates is proposed in this letter. Specifically, the tightly coupled elements in the proposed array are open folded dipoles, in which the gaps provide additional capacitance as compared to normal dipoles, thus resulting in better impedance matching. The proposed antenna array achieves 7.33:1 bandwidth (0.3-2.2 GHz) while scanning up to ±70° in the E-/D-plane and ±50° in the H-plane, subject to VSWR < 3.0. A prototype for an 8 × 8 array was fabricated and measured. Good agreement is achieved between measured and simulation results, thus validating the good performance of the proposed array.
In this paper, we focus on heterogeneous features learning for RGB-D activity recognition. We find that features from different channels (RGB, depth) could share some similar hidden structures, and ...then propose a joint learning model to simultaneously explore the shared and feature-specific components as an instance of heterogeneous multi-task learning. The proposed model formed in a unified framework is capable of: 1) jointly mining a set of subspaces with the same dimensionality to exploit latent shared features across different feature channels, 2) meanwhile, quantifying the shared and feature-specific components of features in the subspaces, and 3) transferring feature-specific intermediate transforms (i-transforms) for learning fusion of heterogeneous features across datasets. To efficiently train the joint model, a three-step iterative optimization algorithm is proposed, followed by a simple inference model. Extensive experimental results on four activity datasets have demonstrated the efficacy of the proposed method. Anew RGB-D activity dataset focusing on human-object interaction is further contributed, which presents more challenges for RGB-D activity benchmarking.
Quantum networks play an extremely important role in quantum information science, with application to quantum communication, computation, metrology, and fundamental tests. One of the key challenges ...for implementing a quantum network is to distribute entangled flying qubits to spatially separated nodes, at which quantum interfaces or transducers map the entanglement onto stationary qubits. The stationary qubits at the separated nodes constitute quantum memories realized in matter while the flying qubits constitute quantum channels realized in photons. Dedicated efforts around the world for more than 20 years have resulted in both major theoretical and experimental progress toward entangling quantum nodes and ultimately building a global quantum network. Here, the development of quantum networks and the experimental progress over the past two decades leading to the current state of the art for generating entanglement of quantum nodes based on various physical systems such as single atoms, cold atomic ensembles, trapped ions, diamonds with nitrogen‐vacancy centers, and solid‐state host doped with rare‐earth ions are reviewed. Along the way, the merits are discussed and the potential of each of these systems toward realizing a quantum network is compared.
Quantum networks linking multiple remote quantum nodes consist of quantum memories served as stationary quantum nodes and flying photonic qubits served as quantum channels. This review summarizes and discusses the state of the art and future challenges for constructing quantum networks in various physical systems like single neutral atoms, cold atomic ensembles, trapped ions, NV centers, and rare‐earth‐ion doped solids.
Background LCAR-B38M is a chimeric antigen receptor T cell product with two binding domains targeting B cell maturation antigen. Our previous reports showed a remarkable efficacy of LCAR-B38M in ...patients with relapsed/refractory multiple myeloma (RRMM) at a median follow-up of 2 years. Here, we report long-term safety and efficacy data from a median follow-up of 4 years. Methods LEGEND-2 was a phase 1, single-arm, open-label study conducted in four registered sites in China. Seventy-four participants with RRMM received LCAR-B38M treatment. Lymphodepletion was performed using cyclophosphamide or cyclophosphamide plus fludarabine. LCAR-B38M, at a median dose of 0.513 x 10.sup.6 cells/kg, was intravenously administered either in three split infusions or in a single infusion. The primary objective was the safety of LCAR-B38M, and the secondary objective was efficacy. Results As of May 25, 2021, the median follow-up was 47.8 months. All patients experienced greater than or equal to 1 adverse events (AEs). Grade greater than or equal to 3 AEs were observed in 45/74 (60.8%) patients. Cytokine release syndrome (CRS) occurred in 68/74 (91.9%) cases; 7 (9.5%) had grade greater than or equal to 3 CRS. One patient experienced grade 1 central nervous system toxicity. The overall response rate was 87.8%. Fifty-four out of 74 (73.0%) patients achieved complete response. The median progression-free survival was 18.0 months, and the median overall survival for all patients was not reached. The median duration of response was 23.3 months. Four patients experienced viral infection more than 6 months post-infusion, and four patients developed second primary non-hematological malignancies at a median time of 11.5 months post-CAR-T cell transfer. Conclusions The 4-year follow-up data of LCAR-B38M therapy demonstrated a favorable long-term safety profile and a durable response in patients with RRMM. Trial registration Clinicaltrials.gov NCT03090659 (retrospectively registered on March 27, 2017); ChiCTR-ONH-17012285. Keywords: Multiple myeloma, Chimeric antigen receptor therapy, B cell maturation antigen, Safety, Efficacy
Carbon dots (CDs) have tremendous potential applications in bioimaging, biomedicine, and optoelectronics. By far, it is still difficult to produce photoluminescence (PL) tunable CDs with high quantum ...yield (QY) across the entire visible spectrum and narrow the emission peak widths of CDs close to those of typical quantum dots. In this work, a series of CDs with tunable emission from 443 to 745 nm, quantum yield within 13–54%, and narrowed full width at half maximum (FWHM) from 108 to 55 nm, are obtained by only adjusting the reaction solvents in a one‐pot solvothermal route. The distinct optical features of these CDs are based on their differences in the particle size, and the content of graphitic nitrogen and oxygen‐containing functional groups, which can be modulated by controlling the dehydration and carbonization processes during solvothermal reactions. Blue, green, yellow, red, and even pure white light emitting films (Commission Internationale de L'Eclairage (CIE)= 0.33, 0.33, QY = 39%) are prepared by dispersing one or three kinds of CDs into polyvinyl alcohol with appropriate ratios. The near‐infrared emissive CDs are excellent fluorescent probes for both in vitro and in vivo bioimaging because of their high QY in water, long‐term stability, and low cytotoxicity.
A solvent‐engineered approach to obtain photoluminescent carbon dots (CDs) with tunable emission from 443 to 745 nm, quantum yield within 13–54%, and narrowed full width at half maximum from 108 to 55 nm is reported. The resulting CDs can be potentially applied in the fabrication of full‐color light‐emitting films and in bioimaging both in vitro and in vivo.
Two lanthanide zeolite-like metal–organic frameworks (Ln-ZMOFs) with rho topology, Tb-ZMOF and Eu-ZMOF, were constructed by self-assembly of a 4-connected lanthanide molecular building block and a ...bipyridine-dicarboxylate ligand. Varying the Tb3+ and Eu3+ ratio during synthesis afforded three mixed-crystal isostructural MZMOFs with variable Eu:Tb stoichiometry. Fluorescence studies revealed that a methanol suspension of one of these mixed crystals, MZMOF-3, exhibits selective detection of lysophosphatidic acid (LPA), a biomarker for ovarian cancer and other gynecologic cancers. Linear correlation between the integrated fluorescence intensity and the concentration of LPA was observed, enabling quantitative analysis of LPA in physiologically relevant ranges (1.4–43.3 μM). MZMOF-3 therefore has the potential to act as a self-referencing and self-calibrating fluorescent indicator for LPA.
Bond formations between two nucleophiles are examined. Chemical reactions during transition metal matalyzed oxidative cross-coupling reactions are also discussed.
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