1,882 research outputs found

    Experimental and Theoretical Advances on Single Atom and Atomic Cluster-Decorated Low-Dimensional Platforms towards Superior Electrocatalysts

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    The fundamental relationship between structure and properties, which is called “structure-property”, plays a vital role in the rational designing of high-performance catalysts for diverse electrocatalytic applications. Low-dimensional (LD) nanomaterials, including 0D, 1D, 2D materials, combined with low-nuclearity metal atoms, ranging from single atoms to subnanometer clusters, are currently emerging as rising star nanoarchitectures for heterogeneous catalysis due to their well-defined active sites and unbeatable metal utilization efficiencies. In this work, a comprehensive experimental and theoretical review is provided on the recent development of single atom and atomic cluster-decorated LD platforms towards some typical clean energy reactions, such as water-splitting, nitrogen fixation, and carbon dioxide reduction reactions. The upmost attractive structural properties, advanced characterization techniques, and theoretical principles of these low-nuclearity electrocatalysts as well as their applications in key electrochemical energy devices are also elegantly discussed

    Immediate Breast Reconstruction (IBR) With Direct, Anatomic, Extra-Projection Prosthesis 102 Cases

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    Abstract: There are different methods described until now for immediate breast reconstruction. Despite the use of autologous flaps considered by many authors, implants are considered as an option by others. A prospective study of 102 clinical cases was designed, including a 1-year follow-up in which glands were reconstructed by immediate breast reconstruction (IBR) with direct, extra projection, anatomic prostheses located in a submuscular pocket after a skin-sparing mastectomy. The prosthesis coverage was made by the muscle in its upper two thirds and by using the skin from the mastectomy in its lower third. The cosmetic results obtained were evaluated according to the volume, form, and symmetry achieved using a linear numeric analogical score. This evaluation had an averaged value of 2.79 Ď® 0.8 in our scale from poor (0) to excellent result (4). The overall rate of complications was 15.7% of the cases, with seroma being the most frequent. In conclusion, this preliminary study demonstrates that immediate breast reconstruction with a direct, extra projection, anatomic prosthesis is a good alternative. Nevertheless, more long-term studies with a higher number of patients and using an SF-36 for patient satisfaction are needed to confirm these results

    Breast tumor segmentation in ultrasound images using contextual-information-aware deep adversarial learning framework.

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    Automatic tumor segmentation in breast ultrasound (BUS) images is still a challenging task because of many sources of uncertainty, such as speckle noise, very low signal-to-noise ratio, shadows that make the anatomical boundaries of tumors ambiguous, as well as the highly variable tumor sizes and shapes. This article proposes an efficient automated method for tumor segmentation in BUS images based on a contextual information-aware conditional generative adversarial learning framework. Specifically, we exploit several enhancements on a deep adversarial learning framework to capture both texture features and contextual dependencies in the BUS images that facilitate beating the challenges mentioned above. First, we adopt atrous convolution (AC) to capture spatial and scale context (i.e., position and size of tumors) to handle very different tumor sizes and shapes. Second, we propose the use of channel attention along with channel weighting (CAW) mechanisms to promote the tumor-relevant features (without extra supervision) and mitigate the effects of artifacts. Third, we propose to integrate the structural similarity index metric (SSIM) and L1-norm in the loss function of the adversarial learning framework to capture the local context information derived from the area surrounding the tumors. We used two BUS image datasets to assess the efficiency of the proposed model. The experimental results show that the proposed model achieves competitive results compared with state-of-the-art segmentation models in terms of Dice and IoU metrics. The source code of the proposed model is publicly available at https://github.com/vivek231/Breast-US-project

    Guidance on noncorticosteroid systemic immunomodulatory therapy in noninfectious uveitis: fundamentals of care for uveitis (focus) initiative

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    Topic: An international, expert-led consensus initiative to develop systematic, evidence-based recommendations for the treatment of noninfectious uveitis in the era of biologics. Clinical Relevance: The availability of biologic agents for the treatment of human eye disease has altered practice patterns for the management of noninfectious uveitis. Current guidelines are insufficient to assure optimal use of noncorticosteroid systemic immunomodulatory agents. Methods: An international expert steering committee comprising 9 uveitis specialists (including both ophthalmologists and rheumatologists) identified clinical questions and, together with 6 bibliographic fellows trained in uveitis, conducted a Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol systematic reviewof the literature (English language studies from January 1996 through June 2016; Medline [OVID], the Central Cochrane library, EMBASE,CINAHL,SCOPUS,BIOSIS, andWeb of Science). Publications included randomized controlled trials, prospective and retrospective studies with sufficient follow-up, case series with 15 cases or more, peer-reviewed articles, and hand-searched conference abstracts from key conferences. The proposed statements were circulated among 130 international uveitis experts for review.Atotal of 44 globally representativegroupmembersmet in late 2016 to refine these guidelines using a modified Delphi technique and assigned Oxford levels of evidence. Results: In total, 10 questions were addressed resulting in 21 evidence-based guidance statements covering the following topics: when to start noncorticosteroid immunomodulatory therapy, including both biologic and nonbiologic agents; what data to collect before treatment; when to modify or withdraw treatment; how to select agents based on individual efficacy and safety profiles; and evidence in specific uveitic conditions. Shared decision-making, communication among providers and safety monitoring also were addressed as part of the recommendations. Pharmacoeconomic considerations were not addressed. Conclusions: Consensus guidelines were developed based on published literature, expert opinion, and practical experience to bridge the gap between clinical needs and medical evidence to support the treatment of patients with noninfectious uveitis with noncorticosteroid immunomodulatory agents
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